WorldWideScience

Sample records for hot light mass

  1. Human eye and the sun hot and cold light

    CERN Document Server

    Vavilov, S I

    1965-01-01

    The Human Eye and the Sun, """"Hot"""" and """"Cold"""" Light is a translation from the Russian language and is a reproduction of texts from Volume IV of S.I. Vavilov, president of the U.S.S.R. Academy of Sciences. The book deals with theoretical and practical developments in lighting techniques. The text gives a brief introduction on the relationship of the human eye and the sun, describing the properties of light, of the sun, and of the human eye. The book describes hot (incandescence) and cold light (luminescence) as coming from different sources. These two types of light are compared. The

  2. Light-Curve Diagnosis of a Hot Spot for Accretion-Disk Models

    OpenAIRE

    FUKUE, Jun

    2003-01-01

    Light curves of a hot spot rotating in a relativistic Keplerian disk were found to be periodic with typically two peaks, originating from a gravitational focusing effect and a Doppler boost. On the other hand, we found that light curves of a hot spot spirally infalling in a sub-Keplerian advective disk are aperiodic with typically a single peak, originating from a gravitational focusing effect or a Doppler boost. Such a difference in the light curves of a hot spot can discriminate background ...

  3. Determining mass-to-light ratios in elliptical galaxies

    International Nuclear Information System (INIS)

    Mathews, W.G.

    1988-01-01

    If the endstate of cooling hot gas in elliptical galaxies is a population of optically dark, low-mass stars near the galactic cores, the mass-to-light ratio could be expected to vary significantly with projected radius. No strong variation in M/L is observed. To investigate the sensitivity and reliability of observational mass-to-light determinations for a variety of galactic parameters, model galaxies having de Vaucouleurs profiles (but with central cores and outer cutoffs), variable velocity ellipsoid structure, and extended dark halos are constructed. Spurious radial variations in M/L can occur when none are present if the properties of the galactic models are processed similar to observational data. Conversely, when a population of diffuse dark stellar matter is added near the galactic cores, large gradients in M/L can escape detection. However, the magnitude of the central velocity dispersion and its variation with projected radius within the effective radius both suggest that a component of dark stars is unlikely to be more massive than about 30 times the core mass of luminous stars. This restriction is important in establishing the initial mass function of stars in elliptical galaxies and the history of winds and cooling inflows in the interstellar medium. 35 references

  4. Origin of warm and hot gas emission from low-mass protostars: Herschel-HIFI observations of CO J = 16-15

    DEFF Research Database (Denmark)

    Kristensen, Lars Egstrøm; Van Dishoeck, E. F.; Mottram, J. C.

    2017-01-01

    Context. Through spectrally unresolved observations of high-J CO transitions, Herschel Photodetector Array Camera and Spectrometer (PACS) has revealed large reservoirs of warm (300 K) and hot (700 K) molecular gas around low-mass protostars. The excitation and physical origin of this gas is still...... in cooling molecular H2-poor gas just prior to the onset of H2 formation. High spectral resolution observations of highly excited CO transitions uniquely shed light on the origin of warm and hot gas in low-mass protostellar objects....... not understood. Aims. We aim to shed light on the excitation and origin of the CO ladder observed toward protostars, and on the water abundance in different physical components within protostellar systems using spectrally resolved Herschel-HIFI data. Methods. Observations are presented of the highly excited CO...

  5. Testing the nature of the supermassive black hole candidate in SgrA* with light curves and images of hot spots

    International Nuclear Information System (INIS)

    Li, Zilong; Kong, Lingyao; Bambi, Cosimo

    2014-01-01

    General relativity makes clear predictions about the spacetime geometry around black holes. In the near future, new facilities will have the capability to explore the metric around SgrA*, the supermassive black hole candidate at the center of our Galaxy, and to open a new window to test the Kerr black hole hypothesis. In this paper, we compute light curves and images associated with compact emission regions (hot spots) orbiting around Kerr and non-Kerr black holes. We study how the analysis of the properties of the radiation emitted by a hot spot can be used to test the Kerr nature of SgrA*. We find that the sole observation of the hot spot light curve can at most constrain a combination of the black hole spin and of possible deviations from the Kerr solution. This happens because the same orbital frequency around a Kerr black hole can be found for a non-Kerr object with a different spin parameter. Second order corrections in the light curve due to the background geometry are typically too small to be identified. While the observation of the hot spot centroid track can potentially bound possible deviations from the Kerr solution, that is out of reach for the near future for the Very Large Telescope Interferometer instrument GRAVITY. The Kerr black hole hypothesis could really be tested in the case of the discovery of a radio pulsar in a compact orbit around SgrA*. Radio observations of such a pulsar would provide precise estimates of the mass and the spin of SgrA*, and the combination of these measurements (probing the weak field) with the hot spot light curve information (probing the strong field) may constrain/find possible deviations from the Kerr solution with quite good precision.

  6. Testing the nature of the supermassive black hole candidate in SgrA* with light curves and images of hot spots

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zilong; Kong, Lingyao; Bambi, Cosimo [Center for Field Theory and Particle Physics and Department of Physics, Fudan University, 200433 Shanghai (China)

    2014-06-01

    General relativity makes clear predictions about the spacetime geometry around black holes. In the near future, new facilities will have the capability to explore the metric around SgrA*, the supermassive black hole candidate at the center of our Galaxy, and to open a new window to test the Kerr black hole hypothesis. In this paper, we compute light curves and images associated with compact emission regions (hot spots) orbiting around Kerr and non-Kerr black holes. We study how the analysis of the properties of the radiation emitted by a hot spot can be used to test the Kerr nature of SgrA*. We find that the sole observation of the hot spot light curve can at most constrain a combination of the black hole spin and of possible deviations from the Kerr solution. This happens because the same orbital frequency around a Kerr black hole can be found for a non-Kerr object with a different spin parameter. Second order corrections in the light curve due to the background geometry are typically too small to be identified. While the observation of the hot spot centroid track can potentially bound possible deviations from the Kerr solution, that is out of reach for the near future for the Very Large Telescope Interferometer instrument GRAVITY. The Kerr black hole hypothesis could really be tested in the case of the discovery of a radio pulsar in a compact orbit around SgrA*. Radio observations of such a pulsar would provide precise estimates of the mass and the spin of SgrA*, and the combination of these measurements (probing the weak field) with the hot spot light curve information (probing the strong field) may constrain/find possible deviations from the Kerr solution with quite good precision.

  7. Static-light meson masses from twisted mass lattice QCD

    International Nuclear Information System (INIS)

    Jansen, Karl; Michael, Chris; Shindler, Andrea; Wagner, Marc

    2008-08-01

    We compute the static-light meson spectrum using two-flavor Wilson twisted mass lattice QCD. We have considered five different values for the light quark mass corresponding to 300 MeV PS S mesons. (orig.)

  8. A UNIFORM SEARCH FOR SECONDARY ECLIPSES OF HOT JUPITERS IN KEPLER Q2 LIGHT CURVES

    International Nuclear Information System (INIS)

    Coughlin, J. L.; López-Morales, M.

    2012-01-01

    In this paper, we present the results of searching the Kepler Q2 public data set for the secondary eclipses of 76 hot Jupiter planet candidates from the list of 1235 candidates published by Borucki et al. This search has been performed by modeling both the Kepler pre-search data conditioned light curves and new light curves produced via our own photometric pipeline. We derive new stellar and planetary parameters for each system, while calculating robust errors for both. We find 16 systems with 1σ-2σ, 14 systems with 2σ-3σ, and 6 systems with >3σ confidence level secondary eclipse detections in at least one light curve produced via the Kepler pre-search data conditioned light curve or our own pipeline; however, results can vary depending on the light curve modeled and whether eccentricity is allowed to vary or not. We estimate false alarm probabilities of 31%, 10%, and 6% for the 1σ-2σ, 2σ-3σ, and >3σ confidence intervals, respectively. Comparing each secondary eclipse result to theoretical expectations, we find that the majority of detected planet candidates emit more light than expected owing to thermal blackbody emission in the optical Kepler bandpass, and present a trend of increasing excess emission with decreasing maximum effective planetary temperature. These results agree with previously published optical secondary eclipse data for other hot Jupiters. We explore modeling biases, significant planetary albedos, non-local thermodynamic equilibrium or other thermal emission, significant internal energy generation, and misidentification of brown dwarfs, low-mass stars, or stellar blends as possible causes of both the excess emission and its correlation with expected planetary temperature. Although we find that no single cause is able to explain all of the planet candidates, significant planetary albedos, with a general trend of increasing planetary albedos with decreasing atmospheric temperatures, are able to explain most of the systems. Identifying

  9. Hot electron spatial distribution under presence of laser light self-focusing in over-dense plasmas

    International Nuclear Information System (INIS)

    Tanimoto, T; Yabuuchi, T; Habara, H; Kondo, K; Kodama, R; Mima, K; Tanaka, K A; Lei, A L

    2008-01-01

    In fast ignition for laser thermonuclear fusion, an ultra intense laser (UIL) pulse irradiates an imploded plasma in order to fast-heat a high-density core with hot electrons generated in laser-plasma interactions. An UIL pulse needs to make plasma channel via laser self-focusing and to propagate through the corona plasma to reach close enough to the core. Hot electrons are used for heating the core. Therefore the propagation of laser light in the high-density plasma region and spatial distribution of hot electron are important in issues in order to study the feasibility of this scheme. We measure the spatial distribution of hot electron when the laser light propagates into the high-density plasma region by self-focusing

  10. The Influence of Coronal Mass Ejections on the Mass-loss Rates of Hot-Jupiters

    Energy Technology Data Exchange (ETDEWEB)

    Cherenkov, A.; Bisikalo, D. [Institute of Astronomy of the Russian Academy of Sciences, 48 Pyatnitskaya St. 119017, Moscow (Russian Federation); Fossati, L.; Möstl, C., E-mail: bisikalo@inasan.ru [Space Research Institute, Austrian Academy of Sciences, Schmiedlstrasse 6, A-8042 Graz (Austria)

    2017-09-01

    Hot-Jupiters are subject to extreme radiation and plasma flows coming from their host stars. Past ultraviolet Hubble Space Telescope observations, supported by hydrodynamic models, confirmed that these factors lead to the formation of an extended envelope, part of which lies beyond the Roche lobe. We use gas-dynamic simulations to study the impact of time variations in the parameters of the stellar wind, namely that of coronal mass ejections (CMEs), on the envelope of the typical hot-Jupiter HD 209458b. We consider three CMEs characterized by different velocities and densities, taking their parameters from typical CMEs observed for the Sun. The perturbations in the ram-pressure of the stellar wind during the passage of each CME tear off most of the envelope that is located beyond the Roche lobe. This leads to a substantial increase of the mass-loss rates during the interaction with the CME. We find that the mass lost by the planet during the whole crossing of a CME is of ≈10{sup 15} g, regardless of the CME taken into consideration. We also find that over the course of 1 Gyr, the mass lost by the planet because of CME impacts is comparable to that lost because of high-energy stellar irradiation.

  11. Propagation of monochromatic light in a hot and dense medium

    Science.gov (United States)

    Masood, Samina S.

    2017-12-01

    Photons, as quanta of electromagnetic fields, determine the electromagnetic properties of an extremely hot and dense medium. Considering the properties of the photons in the interacting medium of charged particles, we explicitly calculate the electromagnetic properties such as the electric permittivity, magnetic permeability, refractive index and the propagation speed of electromagnetic signals in an extremely hot and dense background. Photons acquire a dynamically generated mass in such a medium. The screening mass of the photon, the Debye shielding length and the plasma frequency are calculated as functions of the statistical parameters of the medium. We study the properties of the propagating particles in astrophysical systems of distinct statistical conditions. The modifications in the properties of the medium lead to the equation of state of the system. We mainly calculate all these parameters for extremely high temperatures of the early universe.

  12. Propagation of monochromatic light in a hot and dense medium

    Energy Technology Data Exchange (ETDEWEB)

    Masood, Samina S. [University of Houston Clear Lake, Department of Physical and Applied Sciences, Houston, TX (United States)

    2017-12-15

    Photons, as quanta of electromagnetic fields, determine the electromagnetic properties of an extremely hot and dense medium. Considering the properties of the photons in the interacting medium of charged particles, we explicitly calculate the electromagnetic properties such as the electric permittivity, magnetic permeability, refractive index and the propagation speed of electromagnetic signals in an extremely hot and dense background. Photons acquire a dynamically generated mass in such a medium. The screening mass of the photon, the Debye shielding length and the plasma frequency are calculated as functions of the statistical parameters of the medium. We study the properties of the propagating particles in astrophysical systems of distinct statistical conditions. The modifications in the properties of the medium lead to the equation of state of the system. We mainly calculate all these parameters for extremely high temperatures of the early universe. (orig.)

  13. Development of analysis methodology for hot leg break mass and energy release

    International Nuclear Information System (INIS)

    Song, Jin Ho; Kim, Cheol Woo; Kwon, Young Min; Kim, Sook Kwan

    1995-04-01

    A study for the development of an analysis methodology for hot leg break mass and energy release is performed. For the blowdown period a modified CEFLASH-4A methodology is suggested. For the post blowdown period a modified CONTRAST boil-off model is suggested. By using these computer code improved mass and energy release data are generated. Also, a RELAP5/MOD3 analysis for finally the FLOOD-3 computer code has been modified for use in the analysis of hot leg break. The results of analysis using modified FLOOD-3 are reasonable as we expected and their trends are good. 66 figs., 8 tabs. (Author) .new

  14. Mass-loss evolution of close-in exoplanets: Evaporation of hot Jupiters and the effect on population

    Energy Technology Data Exchange (ETDEWEB)

    Kurokawa, H. [Department of Physics, Nagoya Univsersity, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602 (Japan); Nakamoto, T., E-mail: kurokawa@nagoya-u.jp [Department of Earth and Planetary Sciences, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551 (Japan)

    2014-03-01

    During their evolution, short-period exoplanets may lose envelope mass through atmospheric escape owing to intense X-ray and extreme ultraviolet (XUV) radiation from their host stars. Roche-lobe overflow induced by orbital evolution or intense atmospheric escape can also contribute to mass loss. To study the effects of mass loss on inner planet populations, we calculate the evolution of hot Jupiters considering mass loss of their envelopes and thermal contraction. Mass loss is assumed to occur through XUV-driven atmospheric escape and the following Roche-lobe overflow. The runaway effect of mass loss results in a dichotomy of populations: hot Jupiters that retain their envelopes and super Earths whose envelopes are completely lost. Evolution primarily depends on the core masses of planets and only slightly on migration history. In hot Jupiters with small cores (≅ 10 Earth masses), runaway atmospheric escape followed by Roche-lobe overflow may create sub-Jupiter deserts, as observed in both mass and radius distributions of planetary populations. Comparing our results with formation scenarios and observed exoplanets populations, we propose that populations of closely orbiting exoplanets are formed by capturing planets at/inside the inner edges of protoplanetary disks and subsequent evaporation of sub-Jupiters.

  15. Mass-loss evolution of close-in exoplanets: Evaporation of hot Jupiters and the effect on population

    International Nuclear Information System (INIS)

    Kurokawa, H.; Nakamoto, T.

    2014-01-01

    During their evolution, short-period exoplanets may lose envelope mass through atmospheric escape owing to intense X-ray and extreme ultraviolet (XUV) radiation from their host stars. Roche-lobe overflow induced by orbital evolution or intense atmospheric escape can also contribute to mass loss. To study the effects of mass loss on inner planet populations, we calculate the evolution of hot Jupiters considering mass loss of their envelopes and thermal contraction. Mass loss is assumed to occur through XUV-driven atmospheric escape and the following Roche-lobe overflow. The runaway effect of mass loss results in a dichotomy of populations: hot Jupiters that retain their envelopes and super Earths whose envelopes are completely lost. Evolution primarily depends on the core masses of planets and only slightly on migration history. In hot Jupiters with small cores (≅ 10 Earth masses), runaway atmospheric escape followed by Roche-lobe overflow may create sub-Jupiter deserts, as observed in both mass and radius distributions of planetary populations. Comparing our results with formation scenarios and observed exoplanets populations, we propose that populations of closely orbiting exoplanets are formed by capturing planets at/inside the inner edges of protoplanetary disks and subsequent evaporation of sub-Jupiters.

  16. Simulating at realistic quark masses. Light quark masses

    International Nuclear Information System (INIS)

    Goeckeler, M.; Streuer, T.

    2006-11-01

    We present new results for light quark masses. The calculations are performed using two flavours of O(a) improved Wilson fermions. We have reached lattice spacings as small as a ∝0.07 fm and pion masses down to m π ∝340 MeV in our simulations. This gives us significantly better control on the chiral and continuum extrapolations. (orig.)

  17. Simulating at realistic quark masses. Light quark masses

    Energy Technology Data Exchange (ETDEWEB)

    Goeckeler, M. [Regensburg Univ. (Germany). Inst. fuer Physik 1 - Theoretische Physik; Horsley, R.; Zanotti, J.M. [Edinburgh Univ. (United Kingdom). School of Physics; Nakamura, Y.; Pleiter, D. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Dept. of Mathematical Sciences; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Streuer, T. [Kentucky Univ., Lexington, KY (United States). Dept. of Physics and Astronomy; Stueben, H. [Konrad-Zuse-Zentrum fuer Informationstechnik Berlin (ZIB) (Germany)

    2006-11-15

    We present new results for light quark masses. The calculations are performed using two flavours of O(a) improved Wilson fermions. We have reached lattice spacings as small as a {proportional_to}0.07 fm and pion masses down to m{sub {pi}} {proportional_to}340 MeV in our simulations. This gives us significantly better control on the chiral and continuum extrapolations. (orig.)

  18. Numerology of the light particles masses

    International Nuclear Information System (INIS)

    Anoshin, A.I.

    2002-01-01

    The empirical formulae for the masses of light mesons, barions and u-, d-, s-'current' quarks was obtained. The using of calculated 'precise' current quark masses in QCD is given as an example. (author)

  19. Conduction-driven cooling of LED-based automotive LED lighting systems for abating local hot spots

    Science.gov (United States)

    Saati, Ferina; Arik, Mehmet

    2018-02-01

    Light-emitting diode (LED)-based automotive lighting systems pose unique challenges, such as dual-side packaging (front side for LEDs and back side for driver electronics circuit), size, harsh ambient, and cooling. Packaging for automotive lighting applications combining the advanced printed circuit board (PCB) technology with a multifunctional LED-based board is investigated with a focus on the effect of thermal conduction-based cooling for hot spot abatement. A baseline study with a flame retardant 4 technology, commonly known as FR4 PCB, is first compared with a metal-core PCB technology, both experimentally and computationally. The double-sided advanced PCB that houses both electronics and LEDs is then investigated computationally and experimentally compared with the baseline FR4 PCB. Computational models are first developed with a commercial computational fluid dynamics software and are followed by an advanced PCB technology based on embedded heat pipes, which is computationally and experimentally studied. Then, attention is turned to studying different heat pipe orientations and heat pipe placements on the board. Results show that conventional FR4-based light engines experience local hot spots (ΔT>50°C) while advanced PCB technology based on heat pipes and thermal spreaders eliminates these local hot spots (ΔT<10°C), leading to a higher lumen extraction with improved reliability. Finally, possible design options are presented with embedded heat pipe structures that further improve the PCB performance.

  20. INTERMEDIATE-MASS HOT CORES AT ∼500 AU: DISKS OR OUTFLOWS?

    International Nuclear Information System (INIS)

    Palau, Aina; Girart, Josep M.; Fuente, Asunción; Alonso-Albi, Tomás; Fontani, Francesco; Sánchez-Monge, Álvaro; Boissier, Jérémie; Piétu, Vincent; Neri, Roberto; Busquet, Gemma; Estalella, Robert; Zapata, Luis A.; Zhang, Qizhou; Ho, Paul T. P.; Audard, Marc

    2011-01-01

    Observations with the Plateau de Bure Interferometer in the most extended configuration toward two intermediate-mass star-forming regions, IRAS 22198+6336 and AFGL 5142, reveal the presence of several complex organic molecules at ∼500 AU scales, confirming the presence of hot cores in both regions. The hot cores are not rich in CN-bearing molecules, as often seen in massive hot cores, and are mainly traced by CH 3 CH 2 OH, (CH 2 OH) 2 , CH 3 COCH 3 , and CH 3 OH, with, additionally, CH 3 CHO, CH 3 OD, and HCOOD for IRAS 22198+6336, and C 6 H and O 13 CS for AFGL 5142. The emission of complex molecules is resolved down to sizes of ∼300 and ∼600 AU, for IRAS 22198+6336 and AFGL 5142, respectively, and most likely is tracing protostellar disks rather than flattened envelopes or toroids as is usually found. This is especially clear for the case of IRAS 22198+6336, where we detect a velocity gradient for all the mapped molecules perpendicular to the most chemically rich outflow of the region, yielding a dynamic mass ∼> 4 M ☉ . As for AFGL 5142, the hot core emission is resolved into two elongated cores separated ∼1800 AU. A detailed comparison of the complex molecule peaks to the new CO (2-1) data and H 2 O maser data from the literature suggests also that for AFGL 5142 the complex molecules are mainly associated with disks, except for a faint and extended molecular emission found to the west, which is possibly produced in the interface between one of the outflows and the dense surrounding gas.

  1. Deriving mass-energy equivalence and mass-velocity relation without light

    Science.gov (United States)

    Dai, Youshan; Dai, Liang

    2018-04-01

    Relativity requires that a particle's momentum and energy are the same functions of the particle's velocity in all inertial frames. Using the fact that momentum and energy must transform linearly between reference frames, we present a novel derivation of the mass-energy equivalence, namely, the relation that the energy is proportional to the moving mass, with no postulate about the existence of light or its properties. We further prove the mass-velocity relation without relying on momentum and energy conservation or on the Lorentz transformation. It is demonstrated that neither conservation laws nor the Lorentz transformation are necessary to establish those relations, and that those relations have a wider scope of validity than that of the conservation laws and the invariance of the speed of light.

  2. An analysis methodology for hot leg break mass and energy release

    International Nuclear Information System (INIS)

    Song, Jin Ho; Kwon, Young Min; Kim, Taek Mo; Chung, Hae Yong; Lee, Sang Jong

    1996-07-01

    An analysis methodology for the hot leg break mass and energy release is developed. For the blowdown period a modified CEFLASH-4A analysis is suggested. For the post-blowdown period a new computer model named COMET is developed. Differently from previous post-blowdown analysis model FLOOD3, COMET is capable of analyzing both cold leg and hot leg break cases. The cold leg break model is essentially same as that of FLOOD3 with some improvements. The analysis results by the newly proposed hot leg break model in the COMET is in the same trend as those observed in scaled-down integral experiment. And the analyses results for the UCN 3 and 4 by COMET are qualitatively and quantitatively in good agreement with those predicted by best-estimate analysis by using RELAP5/MOD3. Therefore, the COMET code is validated and can be used for the licensing analysis. 6 tabs., 82 figs., 9 refs. (Author)

  3. INTERMEDIATE-MASS HOT CORES AT {approx}500 AU: DISKS OR OUTFLOWS?

    Energy Technology Data Exchange (ETDEWEB)

    Palau, Aina; Girart, Josep M. [Institut de Ciencies de l' Espai (CSIC-IEEC), Campus UAB-Facultat de Ciencies, Torre C5-parell 2, 08193 Bellaterra, Catalunya (Spain); Fuente, Asuncion; Alonso-Albi, Tomas [Observatorio Astronomico Nacional, P.O. Box 112, 28803 Alcala de Henares, Madrid (Spain); Fontani, Francesco; Sanchez-Monge, Alvaro [Osservatorio Astrofisico di Arcetri, INAF, Largo E. Fermi 5, 50125 Firenze (Italy); Boissier, Jeremie [Istituto di Radioastronomia, INAF, Via Gobetti 101, Bologna (Italy); Pietu, Vincent; Neri, Roberto [IRAM, 300 Rue de la piscine, 38406 Saint Martin d' Heres (France); Busquet, Gemma [Istituto di Fisica dello Spazio Interplanetario, INAF, Area di Recerca di Tor Vergata, Via Fosso Cavaliere 100, 00133 Roma (Italy); Estalella, Robert [Departament d' Astronomia i Meteorologia (IEEC-UB), Institut Ciencies Cosmos, Universitat Barcelona, Marti Franques 1, 08028 Barcelona (Spain); Zapata, Luis A. [Centro de Radioastronomia y Astrofisica, Universidad Nacional Autonoma de Mexico, P.O. Box 3-72, 58090 Morelia, Michoacan (Mexico); Zhang, Qizhou; Ho, Paul T. P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Audard, Marc, E-mail: palau@ieec.uab.es [Geneva Observatory, University of Geneva, Ch. des Maillettes 51, 1290 Versoix (Switzerland)

    2011-12-20

    Observations with the Plateau de Bure Interferometer in the most extended configuration toward two intermediate-mass star-forming regions, IRAS 22198+6336 and AFGL 5142, reveal the presence of several complex organic molecules at {approx}500 AU scales, confirming the presence of hot cores in both regions. The hot cores are not rich in CN-bearing molecules, as often seen in massive hot cores, and are mainly traced by CH{sub 3}CH{sub 2}OH, (CH{sub 2}OH){sub 2}, CH{sub 3}COCH{sub 3}, and CH{sub 3}OH, with, additionally, CH{sub 3}CHO, CH{sub 3}OD, and HCOOD for IRAS 22198+6336, and C{sub 6}H and O{sup 13}CS for AFGL 5142. The emission of complex molecules is resolved down to sizes of {approx}300 and {approx}600 AU, for IRAS 22198+6336 and AFGL 5142, respectively, and most likely is tracing protostellar disks rather than flattened envelopes or toroids as is usually found. This is especially clear for the case of IRAS 22198+6336, where we detect a velocity gradient for all the mapped molecules perpendicular to the most chemically rich outflow of the region, yielding a dynamic mass {approx}> 4 M{sub Sun }. As for AFGL 5142, the hot core emission is resolved into two elongated cores separated {approx}1800 AU. A detailed comparison of the complex molecule peaks to the new CO (2-1) data and H{sub 2}O maser data from the literature suggests also that for AFGL 5142 the complex molecules are mainly associated with disks, except for a faint and extended molecular emission found to the west, which is possibly produced in the interface between one of the outflows and the dense surrounding gas.

  4. Light variations of a spherical star with two hot precessing spots

    International Nuclear Information System (INIS)

    Kyurkchieva, D.P.; Shkodrov, V.G.

    1984-01-01

    In one of the models of SS443, suggested by Lipunov and Shakura (1982), the second component of the double stellar system is considered a star with two hot spots on the surface. Since the gas jets forming the spots are precessing, the hot spots on the visible disk will do likewise. In this paper, the light variations of a spherical star with two precessing hot spots are analyzed under the following restrictive conditions: (I) the inclination of the precession axis toward the line of sight is i=π/2; (II) the visible disk of the spherical star is considered uniformly illuminated, i.e. the effect of the variation in intensity from the disk center to the limb is neglected. The time variations in the projection area of the precessing spots on the visible stellar disk are investigated. In the studies to follow, the same effect will be analyzed assuming: (1) inot=π/2; (2) the variation in intensity is estimated from center to the stellar boundary; (3) a case of ellipsoidal stars; (4) this effect added to the effect of darkening due to orbital movement in a double stellar system

  5. Orbital Light Curves of UU Aquarii in Stunted Outburst

    Science.gov (United States)

    Robertson, J. W.; Honeycutt, R. K.; Henden, A. A.; Campbell, R. T.

    2018-02-01

    Stunted outbursts are ∼0.ͫ6 eruptions, typically lasting 5–10 days, which are found in some novalike cataclysmic variables, including UU Aqr. The mechanism responsible for stunted outbursts is uncertain but is likely related to an accretion disk instability or to variations in the mass transfer rate. A campaign to monitor the eclipse light curves in UU Aqr has been conducted in order to detect any light curve distortions due to the appearance of a hot spot on the disk at the location of the impact point of the accretion stream. If stunted outbursts are due to a temporary mass transfer enhancement, then predictable deformations of the orbital light curve are expected to occur during such outbursts. This study used 156 eclipses on 135 nights during the years 2000–2012. During this interval, random samples found the system to be in stunted outbursts 4%–5% of the time, yielding ∼7 eclipses obtained during some stage of stunted outburst. About half of the eclipses obtained during stunted outbursts showed clear evidence for hot spot enhancement, providing strong evidence that the stunted outbursts in UU Aqr are associated with mass transfer variations. The other half of the eclipses during stunted outburst showed little or no evidence for hot spot enhancement. Furthermore, there were no systematic changes in the hot spot signature as stunted outbursts progressed. Therefore, we have tentatively attributed the changes in hot spot visibility during stunted outburst to random blobby accretion, which likely further modulates the strength of the accretion stream on orbital timescales.

  6. Fragments emission from light mass composite nuclei within collective clusterization mechanism

    International Nuclear Information System (INIS)

    Singh, BirBikram

    2016-01-01

    Based on the quantum mechanical fragmentation theory (QMFT) the dynamical cluster decay model (DCM) has been developed by Gupta and Collaborators to study the decay of hot and rotating compound systems. Number of compound nuclei (CN) in different mass regions have been studied quite extensively while taking into consideration nuclear structure effects in the same. It is quite relevant to mention here that in the binary decay of CN nuclear structure effects comes into picture, within DCM, via preformation probability P_0 of the complimentary fragments before penetrating the potential barrier between them with certain probability P . It is interesting to note here that the statistical models treat various decay modes of the CN on different footing contrary to the DCM. In very light mass region the decay of number of composite systems "2"0","2"1","2"2Ne*, "2"6"-"2"9Al, "2"8Si, "3"1P, "3"2S, "3"9K and "4"0Ca*, formed in low energy heavy ion reactions, have been investigated for different reaction mechanisms particularly fusion-fission (FF) and deep inelastic orbiting (DIO) from equilibrated and non-equilibrated compound nucleus processes, respectively

  7. A CMOS microdisplay with integrated controller utilizing improved silicon hot carrier luminescent light sources

    Science.gov (United States)

    Venter, Petrus J.; Alberts, Antonie C.; du Plessis, Monuko; Joubert, Trudi-Heleen; Goosen, Marius E.; Janse van Rensburg, Christo; Rademeyer, Pieter; Fauré, Nicolaas M.

    2013-03-01

    Microdisplay technology, the miniaturization and integration of small displays for various applications, is predominantly based on OLED and LCoS technologies. Silicon light emission from hot carrier electroluminescence has been shown to emit light visibly perceptible without the aid of any additional intensification, although the electrical to optical conversion efficiency is not as high as the technologies mentioned above. For some applications, this drawback may be traded off against the major cost advantage and superior integration opportunities offered by CMOS microdisplays using integrated silicon light sources. This work introduces an improved version of our previously published microdisplay by making use of new efficiency enhanced CMOS light emitting structures and an increased display resolution. Silicon hot carrier luminescence is often created when reverse biased pn-junctions enter the breakdown regime where impact ionization results in carrier transport across the junction. Avalanche breakdown is typically unwanted in modern CMOS processes. Design rules and process design are generally tailored to prevent breakdown, while the voltages associated with breakdown are too high to directly interact with the rest of the CMOS standard library. This work shows that it is possible to lower the operating voltage of CMOS light sources without compromising the optical output power. This results in more efficient light sources with improved interaction with other standard library components. This work proves that it is possible to create a reasonably high resolution microdisplay while integrating the active matrix controller and drivers on the same integrated circuit die without additional modifications, in a standard CMOS process.

  8. Dim light at night increases body mass of female mice.

    Science.gov (United States)

    Aubrecht, Taryn G; Jenkins, Richelle; Nelson, Randy J

    2015-05-01

    During the past century, the prevalence of light at night has increased in parallel with obesity rates. Dim light at night (dLAN) increases body mass in male mice. However, the effects of light at night on female body mass remain unspecified. Thus, female mice were exposed to a standard light/dark (LD; 16 h light at ∼150 lux/8 h dark at ∼0 lux) cycle or to light/dim light at night (dLAN; 16 h light at ∼150 lux/8 h dim light at ∼5 lux) cycles for six weeks. Females exposed to dLAN increased the rate of change in body mass compared to LD mice despite reduced total food intake during weeks five and six, suggesting that dLAN disrupted circadian rhythms resulting in deranged metabolism.

  9. Dim Light at Night Increases Body Mass of Female Mice

    OpenAIRE

    Aubrecht, Taryn G.; Jenkins, Richelle; Nelson, Randy J.

    2014-01-01

    During the past century the prevalence of light at night has increased in parallel with obesity rates. Dim light at night (dLAN) increases body mass in male mice. However, the effects of light at night on female body mass remain unspecified. Thus, female mice were exposed to a standard light/dark (LD; 16h light at ~150 lux/8h dark at ~0 lux) cycle or to light/dim light at night (dLAN; 16h light at ~150 lux/8h dim light at ~5 lux) cycles for six weeks. Females exposed to dLAN increased the rat...

  10. Hot electron light emission in gallium arsenide/aluminium(x) gallium(1-x) arsenic heterostructures

    Science.gov (United States)

    Teke, Ali

    In this thesis we have demonstrated the operation of a novel tunable wavelength surface light emitting device. The device is based on a p-GaAs, and n-Ga1- xAlxAs heterojunction containing an inversion layer on the p- side, and GaAs quantum wells on the n- side, and, is referred to as HELLISH-2 (Hot Electron Light Emitting and Lasing in Semiconductor Heterostructure-Type 2). The devices utilise hot electron longitudinal transport and, therefore, light emission is independent of the polarity of the applied voltage. The wavelength of the emitted light can be tuned with the applied bias from GaAs band-to-band transition in the inversion layer to e1-hh1 transition in the quantum wells. In this work tunable means that the device can be operated at either single or multiple wavelength emission. The operation of the device requires only two diffused in point contacts. In this project four HELLISH-2 samples coded as ES1, ES2, ES6 and QT919 have been studied. First three samples were grown by MBE and the last one was grown by MOVPE techniques. ES1 was designed for single and double wavelength operation. ES2 was a control sample used to compare our results with previous work on HELLISH-2 and ES6 was designed for single, double and triple wavelength operation. Theoretical modelling of the device operation was carried out and compared with the experimental results. HELLISH-2 structure was optimised for low threshold and high efficiency operation as based on our model calculations. The last sample QT919 has been designed as an optimised device for single and double wavelength operation like ES1. HELLISH-2 has a number of advantages over the conventional light emitters, resulting in some possible applications, such as light logic gates and wavelength division multiplexing in optoelectronic.

  11. Light meson physics from maximally twisted mass lattice QCD

    International Nuclear Information System (INIS)

    Baron, R.; Boucaud, P.

    2009-12-01

    We present a comprehensive investigation of light meson physics using maximally twisted mass fermions for N f =2 mass-degenerate quark flavours. By employing four values of the lattice spacing, spatial lattice extents ranging from 2.0 fm to 2.5 fm and pseudo scalar masses in the range 280 PS < or similar 650 MeV we control the major systematic effects of our calculation. This enables us to confront our data with chiral perturbation theory and extract low energy constants of the effective chiral Lagrangian and derived quantities, such as the light quark mass, with high precision. (orig.)

  12. Mass-to-light ratios of nearby groups of galaxies

    CERN Document Server

    Materne, J

    1980-01-01

    The application of a probability density function gives the possibility of determining groups of galaxies and membership probabilities of the galaxies in a reliable unbiased way. For the five nearest groups so defined, the mean mass-to-light ratio was derived using the concept of negative energy. These groups have a mass-to- light ratio of 16 M/sub (.)//L/sub (.)/. The probability function gives also the possibility of deriving masses of groups in a direct and independent way. (22 refs).

  13. The static-light meson spectrum from twisted mass lattice QCD

    International Nuclear Information System (INIS)

    Jansen, Karl; Michael, Chris; Shindler, Andrea; Wagner, Marc

    2008-10-01

    We compute the static-light meson spectrum with N f =2 flavours of sea quarks using Wilson twisted mass lattice QCD. We consider five different values for the light quark mass corresponding to 300 MeV PS s mesons. (orig.)

  14. Energy savings due to daylight and artificial lighting integration in office buildings in hot climate

    Energy Technology Data Exchange (ETDEWEB)

    Al-Ashwal, Nagib T. [Sana' a University, Sana' a (Yemen); Budaiwi, Ismail M. [King Fahd University of Petroleum and Minerals, Dhahran (Saudi Arabia)

    2011-07-01

    Reducing energy consumption while maintaining acceptable environmental quality in buildings has been a challenging task for building professionals. In office buildings, artificial lighting systems are a major consumer of energy and can significantly contribute to building cooling load. Furthermore, although reliable, artificial lighting does not necessarily provide the required quality of lighting. Significant improvement in lighting quality and energy consumption can be achieved by proper integration of daylight and artificial lighting. The objective of this study is to investigate the energy performance of office buildings resulting from daylight and artificial lighting integration in hot climates. A parametric analysis is conducted to find the impact of different window design parameters, including window area, height and glazing type, on building energy performance. Results have shown that as much as 35% reduction in lighting energy consumption and 13% reduction in total energy consumption can be obtained when proper daylighting and artificial lighting integration is achieved.

  15. Light meson physics from maximally twisted mass lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Baron, R.; Boucaud, P. [Paris XI Univ., 91 - Orsay (France). Lab. de Physique Theorique; Dimopoulos, P. [Roma Tor Vergata Univ. (Italy). Dipt. di Fisica; INFN, Rome (IT)] (and others)

    2009-12-15

    We present a comprehensive investigation of light meson physics using maximally twisted mass fermions for N{sub f}=2 mass-degenerate quark flavours. By employing four values of the lattice spacing, spatial lattice extents ranging from 2.0 fm to 2.5 fm and pseudo scalar masses in the range 280light quark mass, with high precision. (orig.)

  16. Road and street smart lighting control systems as a new application area of the hot-potato protocol

    DEFF Research Database (Denmark)

    Kiedrowski, Piotr; Gutierrez Lopez, Jose Manuel; Boniewicz, Piotr

    2014-01-01

    This paper presents the new application area of the hot-potato routing protocol, which is a “last-mile” communication network for controlling systems of road and street lighting. Four variants of the hot-potato protocol are analyzed with use of the graph theory. For the assessment of the traffic ...... parameters the ETX parameter is used in relation to the length of the shortest path. Proposed methods are independent of the media type and can be implemented either in wireless or PLC....

  17. HOT HIGH-MASS ACCRETION DISK CANDIDATES

    International Nuclear Information System (INIS)

    Beuther, H.; Walsh, A. J.; Longmore, S. N.

    2009-01-01

    To better understand the physical properties of accretion disks in high-mass star formation, we present a study of a dozen high-mass accretion disk candidates observed at high spatial resolution with the Australia Telescope Compact Array (ATCA) in the high-excitation (4,4) and (5,5) lines of NH 3 . All of our originally selected sources were detected in both NH 3 transitions, directly associated with CH 3 OH Class II maser emission and implying that high-excitation NH 3 lines are good tracers of the dense gas components in hot-core-type targets. Only the one source that did not satisfy the initial selection criteria remained undetected. From the 11 mapped sources, six show clear signatures of rotation and/or infall motions. These signatures vary from velocity gradients perpendicular to the outflows, to infall signatures in absorption against ultracompact H II regions, to more spherical infall signatures in emission. Although our spatial resolution is ∼1000 AU, we do not find clear Keplerian signatures in any of the sources. Furthermore, we also do not find flattened structures. In contrast to this, in several of the sources with rotational signatures, the spatial structure is approximately spherical with sizes exceeding 10 4 AU, showing considerable clumpy sub-structure at even smaller scales. This implies that on average typical Keplerian accretion disks-if they exist as expected-should be confined to regions usually smaller than 1000 AU. It is likely that these disks are fed by the larger-scale rotating envelope structure we observe here. Furthermore, we do detect 1.25 cm continuum emission in most fields of view. While in some cases weak cm continuum emission is associated with our targets, more typically larger-scale H II regions are seen offset more than 10'' from our sources. While these H II regions are unlikely to be directly related to the target regions, this spatial association nevertheless additionally stresses that high-mass star formation rarely

  18. THE BLACK HOLE MASS, STELLAR MASS-TO-LIGHT RATIO, AND DARK HALO IN M87

    International Nuclear Information System (INIS)

    Gebhardt, Karl; Thomas, Jens

    2009-01-01

    We model the dynamical structure of M87 (NGC4486) using high spatial resolution long-slit observations of stellar light in the central regions, two-dimensional stellar light kinematics out to half of the effective radius, and globular cluster velocities out to eight effective radii. We simultaneously fit for four parameters: black hole mass, dark halo core radius, dark halo circular velocity, and stellar mass-to-light (M/L) ratio. We find a black hole mass of 6.4(±0.5) x 10 9 M sun (the uncertainty is 68% confidence marginalized over the other parameters). The stellar M/L V = 6.3 ± 0.8. The best-fit dark halo core radius is 14 ± 2 kpc, assuming a cored logarithmic potential. The best-fit dark halo circular velocity is 715 ± 15 km s -1 . Our black hole mass is over a factor of 2 larger than previous stellar dynamical measures, and our derived stellar M/L ratio is two times lower than previous dynamical measures. When we do not include a dark halo, we measure a black hole mass and stellar M/L ratio that is consistent with previous measures, implying that the major difference is in the model assumptions. The stellar M/L ratio from our models is very similar to that derived from stellar population models of M87. The reason for the difference in the black hole mass is because we allow the M/L ratio to change with radius. The dark halo is degenerate with the stellar M/L ratio, which is subsequently degenerate with the black hole mass. We argue that dynamical models of galaxies that do not include the contribution from a dark halo may produce a biased result for the black hole mass. This bias is especially large for a galaxy with a shallow light profile such as M87, and may not be as severe in galaxies with steeper light profiles unless they have a large stellar population change with radius.

  19. Complex molecules in the hot core of the low-mass protostar NGC 1333 IRAS 4A

    NARCIS (Netherlands)

    Bottinelli, S; Ceccarelli, C; Lefloch, B; Williams, JP; Castets, A; Caux, E; Cazaux, S; Maret, S; Parise, B; Tielens, AGGM

    2004-01-01

    We report the detection of complex molecules (HCOOCH3, HCOOH, and CH3CN), signposts of a hot core like region, toward the low-mass Class 0 source NGC 1333 IRAS 4A. This is the second low-mass protostar in which such complex molecules have been searched for and reported, the other source being IRAS

  20. Using Black Light to Find Jack-Pine Budworm Egg Masses

    Science.gov (United States)

    Daniel T. Jennings

    1968-01-01

    Jack pine foliage infested with jack-pine budworm egg masses was examined under two kinds of light -- black light and a combination of natural and fluorescent light. Black light significantly increased the accuracy of count but not the efficiency of examination.

  1. Detection of Hot Halo Gets Theory Out of Hot Water

    Science.gov (United States)

    2006-02-01

    Scientists using NASA's Chandra X-ray Observatory have detected an extensive halo of hot gas around a quiescent spiral galaxy. This discovery is evidence that galaxies like our Milky Way are still accumulating matter from the gradual inflow of intergalactic gas. "What we are likely witnessing here is the ongoing galaxy formation process," said Kristian Pedersen of the University of Copenhagen, Denmark, and lead author of a report on the discovery. Chandra observations show that the hot halo extends more than 60,000 light years on either side of the disk of the galaxy known as NGC 5746. The detection of such a large halo alleviates a long-standing problem for the theory of galaxy formation. Spiral galaxies are thought to form from enormous clouds of intergalactic gas that collapse to form giant, spinning disks of stars and gas. Chandra X-ray Image of NGC 5746 Chandra X-ray Image of NGC 5746 One prediction of this theory is that large spiral galaxies should be immersed in halos of hot gas left over from the galaxy formation process. Hot gas has been detected around spiral galaxies in which vigorous star formation is ejecting matter from the galaxy, but until now hot halos due to infall of intergalactic matter have not been detected. "Our observations solve the mystery of the missing hot halos around spiral galaxies," said Pedersen. "The halos exist, but are so faint that an extremely sensitive telescope such as Chandra is needed to detect them." DSS Optical Image of NGC 5746 DSS Optical Image of NGC 5746 NGC 5746 is a massive spiral galaxy about a 100 million light years from Earth. Its disk of stars and gas is viewed almost edge-on. The galaxy shows no signs of unusual star formation, or energetic activity from its nuclear region, making it unlikely that the hot halo is produced by gas flowing out of the galaxy. "We targeted NGC 5746 because we thought its distance and orientation would give us the best chance to detect a hot halo caused by the infall of

  2. BEER ANALYSIS OF KEPLER AND CoRoT LIGHT CURVES. I. DISCOVERY OF KEPLER-76b: A HOT JUPITER WITH EVIDENCE FOR SUPERROTATION

    International Nuclear Information System (INIS)

    Faigler, S.; Tal-Or, L.; Mazeh, T.; Latham, D. W.; Buchhave, L. A.

    2013-01-01

    We present the first case in which the BEER algorithm identified a hot Jupiter in the Kepler light curve, and its reality was confirmed by orbital solutions based on follow-up spectroscopy. The companion Kepler-76b was identified by the BEER algorithm, which detected the BEaming (sometimes called Doppler boosting) effect together with the Ellipsoidal and Reflection/emission modulations (BEER), at an orbital period of 1.54 days, suggesting a planetary companion orbiting the 13.3 mag F star. Further investigation revealed that this star appeared in the Kepler eclipsing binary catalog with estimated primary and secondary eclipse depths of 5 × 10 –3 and 1 × 10 –4 , respectively. Spectroscopic radial velocity follow-up observations with Tillinghast Reflector Echelle Spectrograph and SOPHIE confirmed Kepler-76b as a transiting 2.0 ± 0.26 M Jup hot Jupiter. The mass of a transiting planet can be estimated from either the beaming or the ellipsoidal amplitude. The ellipsoidal-based mass estimate of Kepler-76b is consistent with the spectroscopically measured mass while the beaming-based estimate is significantly inflated. We explain this apparent discrepancy as evidence for the superrotation phenomenon, which involves eastward displacement of the hottest atmospheric spot of a tidally locked planet by an equatorial superrotating jet stream. This phenomenon was previously observed only for HD 189733b in the infrared. We show that a phase shift of 10.°3 ± 2.°0 of the planet reflection/emission modulation, due to superrotation, explains the apparently inflated beaming modulation, resolving the ellipsoidal/beaming amplitude discrepancy. Kepler-76b is one of very few confirmed planets in the Kepler light curves that show BEER modulations and the first to show superrotation evidence in the Kepler band. Its discovery illustrates for the first time the ability of the BEER algorithm to detect short-period planets and brown dwarfs.

  3. Phenotyping polyclonal kappa and lambda light chain molecular mass distributions in patient serum using mass spectrometry.

    Science.gov (United States)

    Barnidge, David R; Dasari, Surendra; Ramirez-Alvarado, Marina; Fontan, Adrian; Willrich, Maria A V; Tschumper, Renee C; Jelinek, Diane F; Snyder, Melissa R; Dispenzieri, Angela; Katzmann, Jerry A; Murray, David L

    2014-11-07

    We previously described a microLC-ESI-Q-TOF MS method for identifying monoclonal immunoglobulins in serum and then tracking them over time using their accurate molecular mass. Here we demonstrate how the same methodology can be used to identify and characterize polyclonal immunoglobulins in serum. We establish that two molecular mass distributions observed by microLC-ESI-Q-TOF MS are from polyclonal kappa and lambda light chains using a combination of theoretical molecular masses from gene sequence data and the analysis of commercially available purified polyclonal IgG kappa and IgG lambda from normal human serum. A linear regression comparison of kappa/lambda ratios for 74 serum samples (25 hypergammaglobulinemia, 24 hypogammaglobulinemia, 25 normal) determined by microflowLC-ESI-Q-TOF MS and immunonephelometry had a slope of 1.37 and a correlation coefficient of 0.639. In addition to providing kappa/lambda ratios, the same microLC-ESI-Q-TOF MS analysis can determine the molecular mass for oligoclonal light chains observed above the polyclonal background in patient samples. In 2 patients with immune disorders and hypergammaglobulinemia, we observed a skewed polyclonal molecular mass distribution which translated into biased kappa/lambda ratios. Mass spectrometry provides a rapid and simple way to combine the polyclonal kappa/lambda light chain abundance ratios with the identification of dominant monoclonal as well as oligoclonal light chain immunoglobulins. We anticipate that this approach to evaluating immunoglobulin light chains will lead to improved understanding of immune deficiencies, autoimmune diseases, and antibody responses.

  4. AutoLens: Automated Modeling of a Strong Lens's Light, Mass and Source

    Science.gov (United States)

    Nightingale, J. W.; Dye, S.; Massey, Richard J.

    2018-05-01

    This work presents AutoLens, the first entirely automated modeling suite for the analysis of galaxy-scale strong gravitational lenses. AutoLens simultaneously models the lens galaxy's light and mass whilst reconstructing the extended source galaxy on an adaptive pixel-grid. The method's approach to source-plane discretization is amorphous, adapting its clustering and regularization to the intrinsic properties of the lensed source. The lens's light is fitted using a superposition of Sersic functions, allowing AutoLens to cleanly deblend its light from the source. Single component mass models representing the lens's total mass density profile are demonstrated, which in conjunction with light modeling can detect central images using a centrally cored profile. Decomposed mass modeling is also shown, which can fully decouple a lens's light and dark matter and determine whether the two component are geometrically aligned. The complexity of the light and mass models are automatically chosen via Bayesian model comparison. These steps form AutoLens's automated analysis pipeline, such that all results in this work are generated without any user-intervention. This is rigorously tested on a large suite of simulated images, assessing its performance on a broad range of lens profiles, source morphologies and lensing geometries. The method's performance is excellent, with accurate light, mass and source profiles inferred for data sets representative of both existing Hubble imaging and future Euclid wide-field observations.

  5. REVISED MASS-TO-LIGHT RATIOS FOR NEARBY GALAXY GROUPS AND CLUSTERS

    International Nuclear Information System (INIS)

    Shan, Yutong; Courteau, Stéphane; McDonald, Michael

    2015-01-01

    We present a detailed investigation of the cluster stellar mass-to-light (M*/L) ratio and cumulative stellar masses, derived on a galaxy-by-galaxy basis, for 12 massive (M 500 ∼ 10 14 -10 15 M ☉ ), nearby clusters with available optical imaging data from the Sloan Digital Sky Survey Data Release 10 and X-ray data from the Chandra X-ray Observatory. Our method involves a statistical cluster membership using both photometric and spectroscopic redshifts when available to maximize completeness while minimizing contamination effects. We show that different methods of estimating the stellar mass-to-light ratio from observed photometry result in systematic discrepancies in the total stellar masses and average mass-to-light ratios of cluster galaxies. Nonetheless, all conversion methodologies point to a lack of correlation between M*/L i and total cluster mass, even though low-mass groups contain relatively more blue galaxies. We also find no statistically significant correlation between M*/L i and the fraction of blue galaxies (g – i < 0.85). For the mass range covered by our sample, the assumption of a Chabrier initial mass function (IMF) yields an integrated M*/L i ≅ 1.7 ± 0.2 M ☉ /L i, ☉ , a lower value than used in most similar studies, though consistent with the study of low-mass galaxy groups by Leauthaud et al. A light (diet) Salpeter IMF would imply a ∼60% increase in M*/L i

  6. CSI 2264: CHARACTERIZING YOUNG STARS IN NGC 2264 WITH STOCHASTICALLY VARYING LIGHT CURVES

    Energy Technology Data Exchange (ETDEWEB)

    Stauffer, John; Rebull, Luisa; Carey, Sean [Spitzer Science Center, California Institute of Technology, Pasadena, CA 91125 (United States); Cody, Ann Marie [NASA Ames Research Center, Kepler Science Office, Mountain View, CA 94035 (United States); Hillenbrand, Lynne A.; Carpenter, John [Astronomy Department, California Institute of Technology, Pasadena, CA 91125 (United States); Turner, Neal J. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Terebey, Susan [Department of Physics and Astronomy, 5151 State University Drive, California State University at Los Angeles, Los Angeles, CA 90032 (United States); Morales-Calderón, Maria [Centro de Astrobiología, Dpto. de Astrofísica, INTA-CSIC, P.O. BOX 78, E-28691, ESAC Campus, Villanueva de la Cañada, Madrid (Spain); Alencar, Silvia H. P.; McGinnis, Pauline; Sousa, Alana [Departamento de Física—ICEx—UFMG, Av. Antônio Carlos, 6627, 30270-901, Belo Horizonte, MG (Brazil); Bouvier, Jerome; Venuti, Laura [Université de Grenoble, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG), F-38000 Grenoble (France); Hartmann, Lee; Calvet, Nuria [Department of Astronomy, University of Michigan, 500 Church Street, Ann Arbor, MI:48105 (United States); Micela, Giusi; Flaccomio, Ettore [INAF—Osservatorio Astronomico di Palermo, Piazza del Parlamento 1, I-90134, Palermo (Italy); Song, Inseok [Department of Physics and Astronomy, The University of Georgia, Athens, GA 30602-2451 (United States); Gutermuth, Rob, E-mail: stauffer@ipac.caltech.edu [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); and others

    2016-03-15

    We provide CoRoT and Spitzer light curves and other supporting data for 17 classical T Tauri stars in NGC 2264 whose CoRoT light curves exemplify the “stochastic” light curve class as defined in 2014 by Cody et al. The most probable physical mechanism to explain the optical variability within this light curve class is time-dependent mass accretion onto the stellar photosphere, producing transient hot spots. Where we have appropriate spectral data, we show that the veiling variability in these stars is consistent in both amplitude and timescale with the optical light curve morphology. The veiling variability is also well-correlated with the strength of the He i 6678 Å emission line, predicted by models to arise in accretion shocks on or near the stellar photosphere. Stars with accretion burst light curve morphology also have variable mass accretion. The stochastic and accretion burst light curves can both be explained by a simple model of randomly occurring flux bursts, with the stochastic light curve class having a higher frequency of lower amplitude events. Members of the stochastic light curve class have only moderate mass accretion rates. Their Hα profiles usually have blueshifted absorption features, probably originating in a disk wind. The lack of periodic signatures in the light curves suggests that little of the variability is due to long-lived hot spots rotating into or out of our line of sight; instead, the primary driver of the observed photometric variability is likely to be instabilities in the inner disk that lead to variable mass accretion.

  7. Volume dependence of light hadron masses in full lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Orth, B.; Lippert, T.; Schilling, K

    2004-03-01

    The aim of the GRAL project is to simulate full QCD with standard Wilson fermions at light quark masses on small to medium-sized lattices and to obtain infinite-volume results by extrapolation. In order to establish the functional form of the volume dependence we study systematically the finite-size effects in the light hadron spectrum. We give an update on the status of the GRAL project and show that our simulation data for the light hadron masses depend exponentially on the lattice size.

  8. Volume dependence of light hadron masses in full lattice QCD

    International Nuclear Information System (INIS)

    Orth, B.; Lippert, T.; Schilling, K.

    2004-01-01

    The aim of the GRAL project is to simulate full QCD with standard Wilson fermions at light quark masses on small to medium-sized lattices and to obtain infinite-volume results by extrapolation. In order to establish the functional form of the volume dependence we study systematically the finite-size effects in the light hadron spectrum. We give an update on the status of the GRAL project and show that our simulation data for the light hadron masses depend exponentially on the lattice size

  9. Multifragmentation of hot nuclei

    International Nuclear Information System (INIS)

    Tamain, B.

    1990-10-01

    It is difficult to deposit a large amount (∼ 1 Gev) of excitation energy into a nucleus. And if one wants to deposit large excitation energy values, the best way consists of shooting a given target nucleus with several nucleons, which can be achieved by using intermediate energy (10-100 MeV/nucleon) heavy ions. Such very excited objects were named hot nuclei. The study of hot nuclei has been undertaken only for 7 years because intermediate energy heavy ion facilities were not available before. The game is then to determine the decay properties of such nuclei, their limits of existence. Their study is connected with general properties of nuclear matter: namely its equation of state. Of special interest, is the onset of a new decay mechanism: multifragmentation, which is the non-sequential disassembly of a hot nucleus into several light nuclei (often called intermediate-mass fragments or IMF) or particles. This paper, shows how this mechanism can reflect fundamental properties of nuclear matter, but also how its experimental signature is difficult to establish. Multifragmentation has also been studied by using very energetic projectiles (protons and heavy ions) in the relativistic or ultra-relativistic region. The multifragmentation question of hot nuclei is far from being solved. One knows that IMF production increases when the excitation energy brought into a system is strongly increased, but very little is known about the mechanisms involved and a clear onset for multifragmentation is not established

  10. Tank selection for Light Duty Utility Arm (LDUA) system hot testing in a single shell tank

    Energy Technology Data Exchange (ETDEWEB)

    Bhatia, P.K.

    1995-01-31

    The purpose of this report is to recommend a single shell tank in which to hot test the Light Duty Utility Arm (LDUA) for the Tank Waste Remediation System (TWRS) in Fiscal Year 1996. The LDUA is designed to utilize a 12 inch riser. During hot testing, the LDUA will deploy two end effectors (a High Resolution Stereoscopic Video Camera System and a Still/Stereo Photography System mounted on the end of the arm`s tool interface plate). In addition, three other systems (an Overview Video System, an Overview Stereo Video System, and a Topographic Mapping System) will be independently deployed and tested through 4 inch risers.

  11. Tank selection for Light Duty Utility Arm (LDUA) system hot testing in a single shell tank

    International Nuclear Information System (INIS)

    Bhatia, P.K.

    1995-01-01

    The purpose of this report is to recommend a single shell tank in which to hot test the Light Duty Utility Arm (LDUA) for the Tank Waste Remediation System (TWRS) in Fiscal Year 1996. The LDUA is designed to utilize a 12 inch riser. During hot testing, the LDUA will deploy two end effectors (a High Resolution Stereoscopic Video Camera System and a Still/Stereo Photography System mounted on the end of the arm's tool interface plate). In addition, three other systems (an Overview Video System, an Overview Stereo Video System, and a Topographic Mapping System) will be independently deployed and tested through 4 inch risers

  12. Photon mass drag and the momentum of light in a medium

    DEFF Research Database (Denmark)

    Partanen, Mikko; Häyrynen, Teppo; Oksanen, Jani

    2017-01-01

    Conventional theories of electromagnetic waves in a medium assume that the energy propagating with the light pulse in the medium is entirely carried by the field. Thus, the possibility that the optical force field of the light pulse would drive forward an atomic mass density wave (MDW...... field. We show that a light pulse having a total electromagnetic energy (h) over bar omega propagating in a nondispersive medium transfers a mass equal to delta m = (n(2) - 1) (h) over bar omega/c(2), where n is the refractive index. MDW, which carries this mass, consists of atoms, which are more......) and the related kinetic and elastic energies is neglected. In this work, we present foundations of a covariant theory of light propagation in a medium by considering a light wave simultaneously with the dynamics of the medium atoms driven by optoelastic forces between the induced dipoles and the electromagnetic...

  13. Hot spot manifestation in eclipsing dwarf nova HT Cassiopeiae

    OpenAIRE

    Bakowska, K.; Olech, A.

    2014-01-01

    We report the detection of the hot spot in light curves of the eclipsing dwarf nova HT Cassiopeiae during its superoutburst in 2010 November. Analysis of eight reconstructed light curves of the hot spot eclipses showed directly that the brightness of the hot spot was changing significantly during the superoutburst. Thereby, detected hot spot manifestation in HT Cas is the newest observational evidence for the EMT model for dwarf novae.

  14. Is it possible to tell the difference between fermionic and bosonic hot dark matter?

    Energy Technology Data Exchange (ETDEWEB)

    Hannestad, S.; Tu, H. [Aarhus Univ. (Denmark). Dept. of Physics and Astronomy; Ringwald, A.; Wong, Y.Y.Y. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2005-07-01

    We study the difference between thermally produced fermionic and bosonic hot dark matter in detail. In the linear regime of structure formation, their distinct free-streaming behaviours can lead to pronounced differences in the matter power spectrum. While not detectable with current cosmological data, such differences will be clearly observable with upcoming large scale weak lensing surveys for particles as light as m{sub HDM} {proportional_to} 0.2 eV. In the nonlinear regime, bosonic hot dark matter is not subject to the same phase space constraints that severely limit the amount of fermionic hot dark matter infall into cold dark matter halos. Consequently, the overdensities in fermionic and bosonic hot dark matter of equal particle mass can differ by more than a factor of five in the central part of a halo. However, this unique manifestation of quantum statistics may prove very difficult to detect unless the mass of the hot dark matter particle and its decoupling temperature fall within a very narrow window, 1hot dark matter infall may have some observable consequences for the nonlinear power spectrum and hence the weak lensing convergence power spectrum at l {proportional_to} 10{sup 3} {yields} 10{sup 4} at the percent level. (orig.)

  15. RECONSTRUCTING THE STELLAR MASS DISTRIBUTIONS OF GALAXIES USING S4G IRAC 3.6 AND 4.5 μm IMAGES. I. CORRECTING FOR CONTAMINATION BY POLYCYCLIC AROMATIC HYDROCARBONS, HOT DUST, AND INTERMEDIATE-AGE STARS

    International Nuclear Information System (INIS)

    Meidt, Sharon E.; Schinnerer, Eva; Knapen, Johan H.; Bosma, Albert; Athanassoula, E.; Sheth, Kartik; Muñoz-Mateos, Juan-Carlos; Buta, Ronald J.; Zaritsky, Dennis; Hinz, Joannah L.; Skibba, Ramin A.; Laurikainen, Eija; Salo, Heikki; Elmegreen, Debra; Elmegreen, Bruce G.; Gadotti, Dimitri A.; Regan, Michael; Ho, Luis C.; Madore, Barry F.; Gil de Paz, Armando

    2012-01-01

    With the aim of constructing accurate two-dimensional maps of the stellar mass distribution in nearby galaxies from Spitzer Survey of Stellar Structure in Galaxies 3.6 and 4.5 μm images, we report on the separation of the light from old stars from the emission contributed by contaminants. Results for a small sample of six disk galaxies (NGC 1566, NGC 2976, NGC 3031, NGC 3184, NGC 4321, and NGC 5194) with a range of morphological properties, dust content, and star formation histories are presented to demonstrate our approach. To isolate the old stellar light from contaminant emission (e.g., hot dust and the 3.3 μm polycyclic aromatic hydrocarbon (PAH) feature) in the IRAC 3.6 and 4.5 μm bands we use an independent component analysis (ICA) technique designed to separate statistically independent source distributions, maximizing the distinction in the [3.6]-[4.5] colors of the sources. The technique also removes emission from evolved red objects with a low mass-to-light ratio, such as asymptotic giant branch (AGB) and red supergiant (RSG) stars, revealing maps of the underlying old distribution of light with [3.6]-[4.5] colors consistent with the colors of K and M giants. The contaminants are studied by comparison with the non-stellar emission imaged at 8 μm, which is dominated by the broad PAH feature. Using the measured 3.6 μm/8 μm ratio to select individual contaminants, we find that hot dust and PAHs together contribute between ∼5% and 15% to the integrated light at 3.6 μm, while light from regions dominated by intermediate-age (AGB and RSG) stars accounts for only 1%-5%. Locally, however, the contribution from either contaminant can reach much higher levels; dust contributes on average 22% to the emission in star-forming regions throughout the sample, while intermediate-age stars contribute upward of 50% in localized knots. The removal of these contaminants with ICA leaves maps of the old stellar disk that retain a high degree of structural information

  16. 3D geometry measurement of hot cylindric specimen using structured light

    Science.gov (United States)

    Quentin, Lorenz; Beermann, Rüdiger; Pösch, Andreas; Reithmeier, Eduard; Kästner, Markus

    2017-06-01

    We present a fringe projection system to measure glowing hot hybrid components in between production processes. For this a high power green light projector, based on TI DLP technology, is used to create the highest possible contrast between fringes on the red glowing specimen. It has a resolution of 1140 x 912 pixels with a maximum frame rate of 120 images per second for fast measurement. We use a green bandpass filter (525 nm) on the camera lens to block unwanted incoming radiation from the specimen caused by self-emission. Commercial measurement standards are not calibrated for temperatures other than 20° C, so they cannot be used to validate measurement data at the required temperatures of up to 1000°C since thermal expansion invalidates the geometry specification from the calibration data sheet. In our first development we use a uniformly heated pipe made of stainless steel as a dummy specimen to examine the measured geometry data. A pyrometer measures the temperature of the pipe so the expansion can be easily calculated using the thermal expansion coefficient. Different impact and triangulation angles are investigated to identify the effects of hot ambient air on the measurement. The impact of the induced refractive index gradient is examined to check the need for pre-processing steps in the measurement routine.

  17. Influence of light-quark masses in dynamical scale breaking

    International Nuclear Information System (INIS)

    Barcelos Neto, J.; Chanda, R.

    1984-01-01

    It is demonstrated that light quark masses may significantly contribute to the logarithmic scale breaking in deep inelastic electromagnetic lepton-nucleon scattering. This is mainly due to the combination of scale variables together with large 'current' masses for u and d quarks, recently reported in the literature. Upper limits for current masses of u and d quarks, using positivity properties of the forward electromagnetic structure function F 2 of the nucleon are also estimated. (Author) [pt

  18. The formation and deexcitation of hot nuclei in 40Ar + 197Au collisions at 44 and 77 MeV/A. Neutrons emission light charged particles and complex fragments

    International Nuclear Information System (INIS)

    Sokolov, A.

    1990-05-01

    This work is a contribution to the study of the formation and decay of hot nuclei produced in heavy ion collisions at intermediate energies. By studying the system Ar + Au and Ar + Th at 44 MeV/u and 77 MeV/u we first show how to classify events in two groups: peripheral and very dissipative collisions, measuring the number of evaporated neutrons, which depend directly on the violence of the collision. Associated with these neutrons, different deexcitation channels were observed (heavy residues, fission fragments, light charged particles, intermediate mass fragments). The ratio between peripheral and very dissipative collisions was found independent of the system and the same as the one observed at lower incident energy. The most probable neutron multiplicity for very dissipative collisions is not very different at 44 MeV/u and 77 MeV/u. A measurement of the angular distribution of fission fragments and heavy residues was performed. Detected products are essentially associated with large neutron multiplicity and have a cross section close to the one for the very dissipative collisions. The total mass of the fission fragments is close to the mass of the target, while the mass of the heavy residue is much smaller. The backward evaporated light charged particles are also produced in very dissipative collisions. The characteristics of their energy spectra as well as their multiplicities are very similar at 44 MeV/u 77 MeV/u. From the number of evaporated light charged particles, the estimation of the quasi-target excitation energy was done and found to be close to 600 MeV at 44 MeV/u and 77 MeV/u [fr

  19. HOT STARS WITH HOT JUPITERS HAVE HIGH OBLIQUITIES

    International Nuclear Information System (INIS)

    Winn, Joshua N.; Albrecht, Simon; Fabrycky, Daniel; Johnson, John Asher

    2010-01-01

    We show that stars with transiting planets for which the stellar obliquity is large are preferentially hot (T eff > 6250 K). This could explain why small obliquities were observed in the earliest measurements, which focused on relatively cool stars drawn from Doppler surveys, as opposed to hotter stars that emerged more recently from transit surveys. The observed trend could be due to differences in planet formation and migration around stars of varying mass. Alternatively, we speculate that hot-Jupiter systems begin with a wide range of obliquities, but the photospheres of cool stars realign with the orbits due to tidal dissipation in their convective zones, while hot stars cannot realign because of their thinner convective zones. This in turn would suggest that hot Jupiters originate from few-body gravitational dynamics and that disk migration plays at most a supporting role.

  20. Magnetized Converging Flows toward the Hot Core in the Intermediate/High-mass Star-forming Region NGC 6334 V

    International Nuclear Information System (INIS)

    Juárez, Carmen; Girart, Josep M.; Zamora-Avilés, Manuel; Palau, Aina; Ballesteros-Paredes, Javier; Tang, Ya-Wen; Koch, Patrick M.; Liu, Hauyu Baobab; Zhang, Qizhou; Qiu, Keping

    2017-01-01

    We present Submillimeter Array (SMA) observations at 345 GHz toward the intermediate/high-mass cluster-forming region NGC 6334 V. From the dust emission we spatially resolve three dense condensations, the brightest one presenting the typical chemistry of a hot core. The magnetic field (derived from the dust polarized emission) shows a bimodal converging pattern toward the hot core. The molecular emission traces two filamentary structures at two different velocities, separated by 2 km s −1 , converging to the hot core and following the magnetic field distribution. We compare the velocity field and the magnetic field derived from the SMA observations with magnetohydrodynamic simulations of star-forming regions dominated by gravity. This comparison allows us to show how the gas falls in from the larger-scale extended dense core (∼0.1 pc) of NGC 6334 V toward the higher-density hot core region (∼0.02 pc) through two distinctive converging flows dragging the magnetic field, whose strength seems to have been overcome by gravity.

  1. Hot-Electron Intraband Luminescence from Single Hot Spots in Noble-Metal Nanoparticle Films

    Science.gov (United States)

    Haug, Tobias; Klemm, Philippe; Bange, Sebastian; Lupton, John M.

    2015-08-01

    Disordered noble-metal nanoparticle films exhibit highly localized and stable nonlinear light emission from subdiffraction regions upon illumination by near-infrared femtosecond pulses. Such hot spot emission spans a continuum in the visible and near-infrared spectral range. Strong plasmonic enhancement of light-matter interaction and the resulting complexity of experimental observations have prevented the development of a universal understanding of the origin of light emission. Here, we study the dependence of emission spectra on excitation irradiance and provide the most direct evidence yet that the continuum emission observed from both silver and gold nanoparticle aggregate surfaces is caused by recombination of hot electrons within the conduction band. The electron gas in the emitting particles, which is effectively decoupled from the lattice temperature for the duration of emission, reaches temperatures of several thousand Kelvin and acts as a subdiffraction incandescent light source on subpicosecond time scales.

  2. Light quark masses with Nf = 2 Wilson fermions

    International Nuclear Information System (INIS)

    Eicker, N.; Lippert, Th.; Orth, B.; Schilling, K.

    2002-01-01

    We present new data on the mass of the light and strange quarks from SESAM/TχL. The results were obtained on lattice-volumes of 16 3 x 32 and 24 3 x 40 points, with the possibility to investigate finite-size effects. Since the SESAM/TχL ensembles at β = 5.6 have been complemented by configurations with β = 5.5, moreover, we are now able to attempt the continuum extrapolation (CE) of the quark masses with standard Wilson fermions

  3. Masses of light quarks in quantum chromodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Hubschmid, W; Mallik, S [Bern Univ. (Switzerland). Inst. fuer Theoretische Physik

    1982-12-28

    We try to determine light quark masses by considering sum rules for the vacuum expectation value of the time-ordered correlation function of two divergences of the axial vector current. The evaluation is carried out at momenta high enough for the non-perturbative contributions to be negligible. We find that the average mass of the up and down quark at a momentum of 1 GeV lies between 3.3 and 7.9 MeV while that for the strange quark lies between 84 and 212 MeV. The ranges of values reflect predominantly the uncertainty in the absorptive part in the low energy region (approx. <= 1.7 GeV).

  4. A hot Jupiter orbiting a 2-million-year-old solar-mass T Tauri star.

    Science.gov (United States)

    Donati, J F; Moutou, C; Malo, L; Baruteau, C; Yu, L; Hébrard, E; Hussain, G; Alencar, S; Ménard, F; Bouvier, J; Petit, P; Takami, M; Doyon, R; Collier Cameron, A

    2016-06-30

    Hot Jupiters are giant Jupiter-like exoplanets that orbit their host stars 100 times more closely than Jupiter orbits the Sun. These planets presumably form in the outer part of the primordial disk from which both the central star and surrounding planets are born, then migrate inwards and yet avoid falling into their host star. It is, however, unclear whether this occurs early in the lives of hot Jupiters, when they are still embedded within protoplanetary disks, or later, once multiple planets are formed and interact. Although numerous hot Jupiters have been detected around mature Sun-like stars, their existence has not yet been firmly demonstrated for young stars, whose magnetic activity is so intense that it overshadows the radial velocity signal that close-in giant planets can induce. Here we report that the radial velocities of the young star V830 Tau exhibit a sine wave of period 4.93 days and semi-amplitude 75 metres per second, detected with a false-alarm probability of less than 0.03 per cent, after filtering out the magnetic activity plaguing the spectra. We find that this signal is unrelated to the 2.741-day rotation period of V830 Tau and we attribute it to the presence of a planet of mass 0.77 times that of Jupiter, orbiting at a distance of 0.057 astronomical units from the host star. Our result demonstrates that hot Jupiters can migrate inwards in less than two million years, probably as a result of planet–disk interactions.

  5. Exquisite Nova Light Curves from the Solar Mass Ejection Imager (SMEI)

    OpenAIRE

    Hounsell, R.; Bode, M. F.; Hick, P. P.; Buffington, A.; Jackson, B. V.; Clover, J. M.; Shafter, A. W.; Darnley, M. J.; Mawson, N. R.; Steele, I. A.; Evans, A.; Eyres, S. P. S.; O'Brien, T. J.

    2010-01-01

    We present light curves of three classical novae (KT Eridani, V598 Puppis, V1280 Scorpii) and one recurrent nova (RS Ophiuchi) derived from data obtained by the Solar Mass Ejection Imager (SMEI) on board the Coriolis satellite. SMEI provides near complete sky-map coverage with precision visible-light photometry at 102-minute cadence. The light curves derived from these sky maps offer unprecedented temporal resolution around, and especially before, maximum light, a phase of the nova eruption n...

  6. Magnetized Converging Flows toward the Hot Core in the Intermediate/High-mass Star-forming Region NGC 6334 V

    Energy Technology Data Exchange (ETDEWEB)

    Juárez, Carmen; Girart, Josep M. [Institut de Ciències de l’Espai, (CSIC-IEEC), Campus UAB, Carrer de Can Magrans, S/N, E-08193 Cerdanyola del Vallès, Catalonia (Spain); Zamora-Avilés, Manuel; Palau, Aina; Ballesteros-Paredes, Javier [Instituto de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, P.O. Box 3-72, 58090, Morelia, Michoacán (Mexico); Tang, Ya-Wen; Koch, Patrick M.; Liu, Hauyu Baobab [Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei, 10617, Taiwan (China); Zhang, Qizhou [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Qiu, Keping, E-mail: juarez@ice.cat [School of Astronomy and Space Science, Nanjing University, 163 Xianlin Avenue, Nanjing 210023 (China)

    2017-07-20

    We present Submillimeter Array (SMA) observations at 345 GHz toward the intermediate/high-mass cluster-forming region NGC 6334 V. From the dust emission we spatially resolve three dense condensations, the brightest one presenting the typical chemistry of a hot core. The magnetic field (derived from the dust polarized emission) shows a bimodal converging pattern toward the hot core. The molecular emission traces two filamentary structures at two different velocities, separated by 2 km s{sup −1}, converging to the hot core and following the magnetic field distribution. We compare the velocity field and the magnetic field derived from the SMA observations with magnetohydrodynamic simulations of star-forming regions dominated by gravity. This comparison allows us to show how the gas falls in from the larger-scale extended dense core (∼0.1 pc) of NGC 6334 V toward the higher-density hot core region (∼0.02 pc) through two distinctive converging flows dragging the magnetic field, whose strength seems to have been overcome by gravity.

  7. Stimulated Raman scattering and hot-electron production

    International Nuclear Information System (INIS)

    Drake, R.P.; Turner, R.E.; Lasinski, B.F.; Estabrook, K.G.; Campbell, E.M.; Wang, C.L.; Phillion, D.W.; Williams, E.A.; Kruer, W.L.

    1985-01-01

    High-intensity laser light can excite parametric instabilities that scatter or absorb it. One instability that can arise when laser light penetrates a plasma is sub-quarter-critical stimulated Raman (SQSR) scattering. It occurs below the quarter-critical density of the incident light and involves the decay of the incident light wave into a scattered light wave and electron plasma wave. The scattered-light wavelength ranges from 1 to 2 times that of the incident light, depending on the plasma density and temperature. This article reports studies of SQSR scattering and hot-electron production in plasmas produced by irradiating thick gold targets with up to 4 kJ of 0.53-μm light in 1-ns (FWHM) pulses. These studies have important implications for laser fusion. Hot electrons attributed to the SQSR instability can increase the difficulty of achieving high-gain implosions by penetrating and preheating the fusion fuel

  8. Hybrid photonic-plasmonic near-field probe for efficient light conversion into the nanoscale hot spot.

    Science.gov (United States)

    Koshelev, Alexander; Munechika, Keiko; Cabrini, Stefano

    2017-11-01

    In this Letter, we present a design and simulations of the novel hybrid photonic-plasmonic near-field probe. Near-field optics is a unique imaging tool that provides optical images with resolution down to tens of nanometers. One of the main limitations of this technology is its low light sensitivity. The presented hybrid probe solves this problem by combining a campanile plasmonic probe with the photonic layer, consisting of the diffractive optic element (DOE). The DOE is designed to match the plasmonic field at the broad side of the campanile probe with the fiber mode. This makes it possible to optimize the size of the campanile tip to convert light efficiently into the hot spot. The simulations show that the hybrid probe is ∼540 times more efficient compared with the conventional campanile on average in the 600-900 nm spectral range.

  9. HOT DUST OBSCURED GALAXIES WITH EXCESS BLUE LIGHT: DUAL AGN OR SINGLE AGN UNDER EXTREME CONDITIONS?

    Energy Technology Data Exchange (ETDEWEB)

    Assef, R. J.; Diaz-Santos, T. [Núcleo de Astronomía de la Facultad de Ingeniería, Universidad Diego Portales, Av. Ejército Libertador 441, Santiago (Chile); Walton, D. J.; Brightman, M. [Space Radiation Laboratory, California Institute of Technology, Pasadena, CA 91125 (United States); Stern, D.; Eisenhardt, P. R. M.; Tsai, C.-W. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Mail Stop 169-236, Pasadena, CA 91109 (United States); Alexander, D. [Department of Physics, Durham University, Durham DH1 3LE (United Kingdom); Bauer, F. [Departamento de Astronomía y Astrofísica, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22 (Chile); Blain, A. W. [Physics and Astronomy, University of Leicester, 1 University Road, Leicester LE1 7RH (United Kingdom); Finkelstein, S. L. [The University of Texas at Austin, 2515 Speedway, Stop C1400, Austin, TX 78712 (United States); Hickox, R. C. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, NH 03755 (United States); Wu, J. W., E-mail: roberto.assef@mail.udp.cl [UCLA Astronomy, P.O. Box 951547, Los Angeles, CA 90095-1547 (United States)

    2016-03-10

    Hot dust-obscured galaxies (Hot DOGs) are a population of hyper-luminous infrared galaxies identified by the Wide-field Infrared Survey Explorer (WISE) mission from their very red mid-IR colors, and characterized by hot dust temperatures (T > 60 K). Several studies have shown clear evidence that the IR emission in these objects is powered by a highly dust-obscured active galactic nucleus (AGN) that shows close to Compton-thick absorption at X-ray wavelengths. Thanks to the high AGN obscuration, the host galaxy is easily observable, and has UV/optical colors usually consistent with those of a normal galaxy. Here we discuss a sub-population of eight Hot DOGs that show enhanced rest-frame UV/optical emission. We discuss three scenarios that might explain the excess UV emission: (i) unobscured light leaked from the AGN by reflection over the dust or by partial coverage of the accretion disk; (ii) a second unobscured AGN in the system; or (iii) a luminous young starburst. X-ray observations can help discriminate between these scenarios. We study in detail the blue excess Hot DOG WISE J020446.13–050640.8, which was serendipitously observed by Chandra/ACIS-I for 174.5 ks. The X-ray spectrum is consistent with a single, hyper-luminous, highly absorbed AGN, and is strongly inconsistent with the presence of a secondary unobscured AGN. Based on this, we argue that the excess blue emission in this object is most likely either due to reflection or a co-eval starburst. We favor the reflection scenario as the unobscured star formation rate needed to power the UV/optical emission would be ≳1000 M{sub ⊙} yr{sup −1}. Deep polarimetry observations could confirm the reflection hypothesis.

  10. HOT DUST OBSCURED GALAXIES WITH EXCESS BLUE LIGHT: DUAL AGN OR SINGLE AGN UNDER EXTREME CONDITIONS?

    International Nuclear Information System (INIS)

    Assef, R. J.; Diaz-Santos, T.; Walton, D. J.; Brightman, M.; Stern, D.; Eisenhardt, P. R. M.; Tsai, C.-W.; Alexander, D.; Bauer, F.; Blain, A. W.; Finkelstein, S. L.; Hickox, R. C.; Wu, J. W.

    2016-01-01

    Hot dust-obscured galaxies (Hot DOGs) are a population of hyper-luminous infrared galaxies identified by the Wide-field Infrared Survey Explorer (WISE) mission from their very red mid-IR colors, and characterized by hot dust temperatures (T > 60 K). Several studies have shown clear evidence that the IR emission in these objects is powered by a highly dust-obscured active galactic nucleus (AGN) that shows close to Compton-thick absorption at X-ray wavelengths. Thanks to the high AGN obscuration, the host galaxy is easily observable, and has UV/optical colors usually consistent with those of a normal galaxy. Here we discuss a sub-population of eight Hot DOGs that show enhanced rest-frame UV/optical emission. We discuss three scenarios that might explain the excess UV emission: (i) unobscured light leaked from the AGN by reflection over the dust or by partial coverage of the accretion disk; (ii) a second unobscured AGN in the system; or (iii) a luminous young starburst. X-ray observations can help discriminate between these scenarios. We study in detail the blue excess Hot DOG WISE J020446.13–050640.8, which was serendipitously observed by Chandra/ACIS-I for 174.5 ks. The X-ray spectrum is consistent with a single, hyper-luminous, highly absorbed AGN, and is strongly inconsistent with the presence of a secondary unobscured AGN. Based on this, we argue that the excess blue emission in this object is most likely either due to reflection or a co-eval starburst. We favor the reflection scenario as the unobscured star formation rate needed to power the UV/optical emission would be ≳1000 M ⊙ yr −1 . Deep polarimetry observations could confirm the reflection hypothesis

  11. X-ray emission from hot subdwarfs with compact companions

    Directory of Open Access Journals (Sweden)

    Esposito P.

    2013-03-01

    Full Text Available We review the X-ray observations of hot subdwarf stars. While no X-ray emission has been detected yet from binaries containing B-type subdwarfs, interesting results have been obtained in the case of the two luminous O-type subdwarfs HD 49798 and BD + 37° 442. Both of them are members of binary systems in which the X-ray luminosity is powered by accretion onto a compact object: a rapidly spinning (13.2 s and massive (1.28  M⊙ white dwarf in the case of HD 49798 and most likely a neutron star, spinning at 19.2 s, in the case of BD + 37° 442. Their study can shed light on the poorly known processes taking place during common envelope evolutionary phases and on the properties of wind mass loss from hot subdwarfs.

  12. Hot Carrier Generation and Extraction of Plasmonic Alloy Nanoparticles.

    Science.gov (United States)

    Valenti, Marco; Venugopal, Anirudh; Tordera, Daniel; Jonsson, Magnus P; Biskos, George; Schmidt-Ott, Andreas; Smith, Wilson A

    2017-05-17

    The conversion of light to electrical and chemical energy has the potential to provide meaningful advances to many aspects of daily life, including the production of energy, water purification, and optical sensing. Recently, plasmonic nanoparticles (PNPs) have been increasingly used in artificial photosynthesis (e.g., water splitting) devices in order to extend the visible light utilization of semiconductors to light energies below their band gap. These nanoparticles absorb light and produce hot electrons and holes that can drive artificial photosynthesis reactions. For n-type semiconductor photoanodes decorated with PNPs, hot charge carriers are separated by a process called hot electron injection (HEI), where hot electrons with sufficient energy are transferred to the conduction band of the semiconductor. An important parameter that affects the HEI efficiency is the nanoparticle composition, since the hot electron energy is sensitive to the electronic band structure of the metal. Alloy PNPs are of particular importance for semiconductor/PNPs composites, because by changing the alloy composition their absorption spectra can be tuned to accurately extend the light absorption of the semiconductor. This work experimentally compares the HEI efficiency from Ag, Au, and Ag/Au alloy nanoparticles to TiO 2 photoanodes for the photoproduction of hydrogen. Alloy PNPs not only exhibit tunable absorption but can also improve the stability and electronic and catalytic properties of the pure metal PNPs. In this work, we find that the Ag/Au alloy PNPs extend the stability of Ag in water to larger applied potentials while, at the same time, increasing the interband threshold energy of Au. This increasing of the interband energy of Au suppresses the visible-light-induced interband excitations, favoring intraband excitations that result in higher hot electron energies and HEI efficiencies.

  13. Hot Weather Tips

    Science.gov (United States)

    ... the person plenty of water and fruit or vegetable juice even if they say they’re not thirsty. No alcohol, coffee or tea. Seek medical help if you suspect dehydration. Light meals: Avoid hot, heavy meals and don’ ...

  14. HOT GAS HALOS IN EARLY-TYPE FIELD GALAXIES

    International Nuclear Information System (INIS)

    Mulchaey, John S.; Jeltema, Tesla E.

    2010-01-01

    We use Chandra and XMM-Newton to study the hot gas content in a sample of field early-type galaxies. We find that the L X -L K relationship is steeper for field galaxies than for comparable galaxies in groups and clusters. The low hot gas content of field galaxies with L K ∼ * suggests that internal processes such as supernovae-driven winds or active galactic nucleus feedback expel hot gas from low-mass galaxies. Such mechanisms may be less effective in groups and clusters where the presence of an intragroup or intracluster medium can confine outflowing material. In addition, galaxies in groups and clusters may be able to accrete gas from the ambient medium. While there is a population of L K ∼ * galaxies in groups and clusters that retain hot gas halos, some galaxies in these rich environments, including brighter galaxies, are largely devoid of hot gas. In these cases, the hot gas halos have likely been removed via ram pressure stripping. This suggests a very complex interplay between the intragroup/intracluster medium and hot gas halos of galaxies in rich environments, with the ambient medium helping to confine or even enhance the halos in some cases and acting to remove gas in others. In contrast, the hot gas content of more isolated galaxies is largely a function of the mass of the galaxy, with more massive galaxies able to maintain their halos, while in lower mass systems the hot gas escapes in outflowing winds.

  15. The light gluino mass window revisited

    CERN Document Server

    Janot, Patrick

    2003-01-01

    The precise measurements of the ``electroweak observables'' performed at LEP and SLC are well consistent with the standard model predictions. Deviations from the standard model arising from vacuum polarization diagrams (also called ``weak loop corrections'') have been constrained in a model-independent manner with the epsilon formalism. Within the same formalism, additional deviations from new physics production processes can also be constrained, still in a model-independent way. For instance, a 95% C.L. limit of Delta Gamma_had} q qbar gluino gluino process, it allows an absolute lower limit to be set on the gluino mass, m_gluino > 6.3 GeV/c2 at 95% C.L., which definitely closes the so-called light gluino mass window. The precise measurements of the "electroweak observables" performed at LEP and SLC are well consistent with the standard model predictions. Deviations from the standard model arising from vacuum polarization diagrams (also called "weak loop corrections") have been constrained in a model-indepe...

  16. A measurement concept for hot-spot BRDFs from space

    Energy Technology Data Exchange (ETDEWEB)

    Gerstl, S.A.W.

    1996-09-01

    Several concepts for canopy hot-spot measurements from space have been investigated. The most promising involves active illumination and bistatic detection that would allow hot-spot angular distribution (BRDF) measurements from space in a search-light mode. The concept includes a pointable illumination source, such as a laser operating at an atmospheric window wavelength, coupled with a number of high spatial-resolution detectors that are clustered around the illumination source in space, receiving photons nearly coaxial with the reto-reflection direction. Microwave control and command among the satellite cluster would allow orienting the direction of the laser beam as well as the focusing detectors simultaneously so that the coupled system can function like a search light with almost unlimited pointing capabilities. The concept is called the Hot-Spot Search-Light (HSSL) satellite. A nominal satellite altitude of 600 km will allow hot-spot BRDF measurements out to about 18 degrees phase angle. The distributed are taking radiometric measurements of the intensity wings of the hot-spot angular distribution without the need for complex imaging detectors. The system can be operated at night for increased signal-to-noise ratio. This way the hot-spot angular signatures can be quantified and parameterized in sufficient detail to extract the biophysical information content of plant architectures.

  17. A measurement concept for hot-spot BRDFs from space

    Science.gov (United States)

    Gerstl, S.A.W.

    1996-01-01

    Several concepts for canopy hot-spot measurements from space have been investigated. The most promising involves active illumination and bistatic detection that would allow hot-spot angular distribution (BRDF) measurements from space in a search-light mode. The concept includes a pointable illumination source, such as a laser operating at an atmospheric window wavelength, coupled with a number of high spatial-resolution detectors that are clustered around the illumination source in space, receiving photons nearly coaxial with the reto-reflection direction. Microwave control and command among the satellite cluster would allow orienting the direction of the laser beam as well as the focusing detectors simultaneously so that the coupled system can function like a search light with almost unlimited pointing capabilities. The concept is called the Hot-Spot Search-Light (HSSL) satellite. A nominal satellite altitude of 600 km will allow hot-spot BRDF measurements out to about 18 degrees phase angle. The distributed are taking radiometric measurements of the intensity wings of the hot-spot angular distribution without the need for complex imaging detectors. The system can be operated at night for increased signal-to-noise ratio. This way the hot-spot angular signatures can be quantified and parameterized in sufficient detail to extract the biophysical information content of plant architectures.

  18. X-ray and SZ constraints on the properties of hot CGM

    Science.gov (United States)

    Singh, Priyanka; Majumdar, Subhabrata; Nath, Biman B.; Silk, Joseph

    2018-05-01

    We use observations of stacked X-ray luminosity and Sunyaev-Zel'dovich (SZ) signal from a cosmological sample of ˜80, 000 and 104,000 massive galaxies, respectively, with 1012.6 ≲ M500 ≲ 1013M⊙ and mean redshift, z¯ ˜ 0.1 - 0.14 to constrain the hot Circumgalactic Medium (CGM) density and temperature. The X-ray luminosities constrain the density and hot CGM mass, while the SZ signal helps in breaking the density-temperature degeneracy. We consider a simple power-law density distribution (ne∝r-3β) as well as a hydrostatic hot halo model, with the gas assumed to be isothermal in both cases. The datasets are best described by the mean hot CGM profile ∝r-1.2, which is shallower than an NFW profile. For halo virial mass ˜1012 - 1013M⊙, the hot CGM contains ˜ 20 - 30% of galactic baryonic mass for the power-law model and 4 - 11% for the hydrostatic halo model, within the virial radii. For the power-law model, the hot CGM profile broadly agrees with observations of the Milky Way. The mean hot CGM mass is comparable to or larger than the mass contained in other phases of the CGM for L* galaxies.

  19. Exquisite Nova Light Curves from the Solar Mass Ejection Imager (SMEI)

    Science.gov (United States)

    Hounsell, R.; Bode, M. F.; Hick, P. P.; Buffington, A.; Jackson, B. V.; Clover, J. M.; Shafter, A. W.; Darnley, M. J.; Mawson, N. R.; Steele, I. A.; Evans, A.; Eyres, S. P. S.; O'Brien, T. J.

    2010-11-01

    We present light curves of three classical novae (CNe; KT Eridani, V598 Puppis, V1280 Scorpii) and one recurrent nova (RS Ophiuchi) derived from data obtained by the Solar Mass Ejection Imager (SMEI) on board the Coriolis satellite. SMEI provides near complete skymap coverage with precision visible-light photometry at 102 minute cadence. The light curves derived from these skymaps offer unprecedented temporal resolution around, and especially before, maximum light, a phase of the eruption normally not covered by ground-based observations. They allow us to explore fundamental parameters of individual objects including the epoch of the initial explosion, the reality and duration of any pre-maximum halt (found in all three fast novae in our sample), the presence of secondary maxima, speed of decline of the initial light curve, plus precise timing of the onset of dust formation (in V1280 Sco) leading to estimation of the bolometric luminosity, white dwarf mass, and object distance. For KT Eri, Liverpool Telescope SkyCamT data confirm important features of the SMEI light curve and overall our results add weight to the proposed similarities of this object to recurrent rather than to CNe. In RS Oph, comparison with hard X-ray data from the 2006 outburst implies that the onset of the outburst coincides with extensive high-velocity mass loss. It is also noted that two of the four novae we have detected (V598 Pup and KT Eri) were only discovered by ground-based observers weeks or months after maximum light, yet these novae reached peak magnitudes of 3.46 and 5.42, respectively. This emphasizes the fact that many bright novae per year are still overlooked, particularly those of the very fast speed class. Coupled with its ability to observe novae in detail even when relatively close to the Sun in the sky, we estimate that as many as five novae per year may be detectable by SMEI.

  20. Mass-polariton theory of light in dispersive media

    Science.gov (United States)

    Partanen, Mikko; Tulkki, Jukka

    2017-12-01

    We have recently shown that the electromagnetic pulse in a medium is made of mass-polariton (MP) quasiparticles, which are quantized coupled states of the field and an atomic mass density wave (MDW) [M. Partanen et al., Phys. Rev. A 95, 063850 (2017), 10.1103/PhysRevA.95.063850]. In this work, we generalize the MP theory of light for dispersive media assuming that absorption and scattering losses are very small. Following our previous work, we present two different approaches to the coupled state of light: (1) the MP quasiparticle theory, which is derived by only using the fundamental conservation laws and the Lorentz transformation; (2) the classical optoelastic continuum dynamics (OCD), which is a generalization of the electrodynamics of continuous media to include the dynamics of the medium under the influence of optical forces. We show that the total momentum and the transferred mass of the light pulse can be determined in a straightforward way if we know the field energy of the pulse and the dispersion relation of the medium. In analogy to the nondispersive case, we also find unambiguous correspondence between the MP and OCD theories. For the coupled MP state of a single photon and the medium, we obtain the total MP momentum pMP=npℏ ω /c , where np is the phase refractive index. The field's share of the MP momentum is equal to pfield=ℏ ω /(ngc ) , where ng is the group refractive index and the share of the MDW is equal to pMDW=pMP-pfield . Thus, as in a nondispersive medium, the total momentum of the MP is equal to the Minkowski momentum and the field's share of the momentum is equal to the Abraham momentum. We also show that the correspondence between the MP and OCD models and the conservation of momentum at interfaces gives an unambiguous formula for the optical force. The dynamics of the light pulse and the related MDW lead to nonequilibrium of the medium and to relaxation of the atomic density by sound waves in the same way as for nondispersive media

  1. Cosmological constraint on the light gravitino mass from CMB lensing and cosmic shear

    Energy Technology Data Exchange (ETDEWEB)

    Osato, Ken; Yoshida, Naoki [Department of Physics, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo, 113-0033 (Japan); Sekiguchi, Toyokazu [University of Helsinki and Helsinki Institute of Physics, P.O. Box 64, FI-00014, Helsinki (Finland); Shirasaki, Masato [National Astronomical Observatory of Japan, Mitaka, Tokyo, 181-8588 (Japan); Kamada, Ayuki, E-mail: ken.osato@utap.phys.s.u-tokyo.ac.jp, E-mail: toyokazu.sekiguchi@gmail.com, E-mail: masato.shirasaki@nao.ac.jp, E-mail: ayuki.kamada@ucr.edu, E-mail: naoki.yoshida@phys.s.u-tokyo.ac.jp [Department of Physics and Astronomy, University of California, Riverside, California 92521 (United States)

    2016-06-01

    Light gravitinos of mass ∼< O (10) eV are of particular interest in cosmology, offering various baryogenesis scenarios without suffering from the cosmological gravitino problem. The gravitino may contribute considerably to the total matter content of the Universe and affect structure formation from early to present epochs. After the gravitinos decouple from other particles in the early Universe, they free-stream and consequently suppress density fluctuations of (sub-)galactic length scales. Observations of structure at the relevant length-scales can be used to infer or constrain the mass and the abundance of light gravitinos. We derive constraints on the light gravitino mass using the data of cosmic microwave background (CMB) lensing from Planck and of cosmic shear from the Canada France Hawaii Lensing Survey survey, combined with analyses of the primary CMB anisotropies and the signature of baryon acoustic oscillations in galaxy distributions. The obtained constraint on the gravitino mass is m {sub 3/2} < 4.7 eV (95 % C.L.), which is substantially tighter than the previous constraint from clustering analysis of Ly-α forests.

  2. CROSS-CORRELATION WEAK LENSING OF SDSS GALAXY CLUSTERS. III. MASS-TO-LIGHT RATIOS

    International Nuclear Information System (INIS)

    Sheldon, Erin S.; Johnston, David E.; Masjedi, Morad; Blanton, Michael R.; McKay, Timothy A.; Scranton, Ryan; Wechsler, Risa H.; Koester, Benjamin P.; Hansen, Sarah M.; Frieman, Joshua A.; Annis, James

    2009-01-01

    We present measurements of the excess mass-to-light ratio (M/L) measured around MaxBCG galaxy clusters observed in the Sloan Digital Sky Survey. This red-sequence cluster sample includes objects from small groups with M 200 ∼ 5 x 10 12 h -1 M sun to clusters with M 200 ∼ 10 15 h -1 M sun . Using cross-correlation weak lensing, we measure the excess mass density profile above the universal mean Δρ(r)=ρ(r)-ρ-bar for clusters in bins of richness and optical luminosity. We also measure the excess luminosity density Δl(r)=l(r)-l-bar measured in the z = 0.25 i band. For both mass and light, we de-project the profiles to produce three-dimensional mass and light profiles over scales from 25 h -1 kpc to 22 h -1 Mpc. From these profiles we calculate the cumulative excess mass ΔM(r) and excess light ΔL(r) as a function of separation from the BCG. On small scales, where ρ(r)>>ρ-bar, the integrated mass-to-light profile (ΔM/ΔL)(r) may be interpreted as the cluster M/L. We find the (ΔM/ΔL) 200 , the M/L within r 200 , scales with cluster mass as a power law with index 0.33 ± 0.02. On large scales, where ρ(r)∼ρ-bar, the ΔM/ΔL approaches an asymptotic value independent of cluster richness. For small groups, the mean (ΔM/ΔL) 200 is much smaller than the asymptotic value, while for large clusters (ΔM/ΔL) 200 is consistent with the asymptotic value. This asymptotic value should be proportional to the mean M/L of the universe (M/L). We find (M/L)b -2 M/L = 362 ± 54h (statistical). There is additional uncertainty in the overall calibration at the ∼10% level. The parameter b 2 M/L is primarily a function of the bias of the L ∼ * galaxies used as light tracers, and should be of order unity. Multiplying by the luminosity density in the same bandpass we find Ω m b -2 M/L = 0.20 ± 0.03, independent of the Hubble parameter.

  3. Light-Time Effect and Mass Transfer in the Triple Star SW Lyncis

    Directory of Open Access Journals (Sweden)

    Chun-Hwey Kim

    1999-06-01

    Full Text Available In this paper all the photoelectric times of minimum for the triple star SW Lyn have been analyzed in terms of light-time e ect due to the third-body and secular period decreases induced by mass transfer process. The light-time orbit determined recently by Ogloza et al.(1998 were modi ed and improved. And it is found that the orbital period of SW Lyn have been decreasing secularly. The third-body revolves around the mass center of triple stars every 5y.77 in a highly eccentric elliptical orbit(e=0.61. The third-body with a minimum mass of 1.13M may be a binary or a white dwarf. The rate of secular period-decrease were obtained as ¡âP/P = -12.45 x 10^-11, implying the mass-transfer from the massive primary star to the secondary. The mass losing rate from the primary were calculated as about 1.24 x 10^-8M /y. It is noticed that the mass-transfer in SW Lyn system is opposite in direction to that deduced from it's Roche geometry by previous investigators.

  4. Closing the light sbottom mass window from a compilation of $e^+ e^- \\to$ hadron data

    CERN Document Server

    AUTHOR|(CDS)2051271

    2004-01-01

    The e+e- -> hadron cross section data from PEP, PETRA, TRISTAN, SLC and LEP, at centre-of-mass energies between 20 to 209GeV, are analysed to search for the production of a pair of light sbottoms decaying hadronically via R-parity-violating couplings. This analysis allows the 95% C.L. exclusion of such a particle if its mass is below 7.5GeV/c2. The light sbottom mass window is closed.

  5. Conformal Gauge Mediation and Light Gravitino of Mass m3/2 < O(10) eV

    International Nuclear Information System (INIS)

    Ibe, M.; SLAC; Nakayama, Y.; Yanagida, T.T.

    2008-01-01

    We discuss a class of gauge mediated supersymmetry breaking models with conformal invariance above the messenger mass scale (conformal gauge mediation). The spectrum of the supersymmetric particles including the gravitino is uniquely determined by the messenger mass. When the conformal fixed point is strongly interacting, it predicts a light gravitino of mass m 3/2 < O(10) eV, which is attractive since such a light gravitino causes no problem in cosmology

  6. Light stop mass limits from Higgs rate measurements in the MSSM: is MSSM electroweak baryogenesis still alive after all?

    Energy Technology Data Exchange (ETDEWEB)

    Liebler, Stefan [Deutsches Elektronen-Synchrotron (DESY),Notkestraße 85, 22607 Hamburg (Germany); Profumo, Stefano; Stefaniak, Tim [Department of Physics and Santa Cruz Institute for Particle Physics (SCIPP),University of California Santa Cruz, CA 95064 (United States)

    2016-04-22

    We investigate the implications of the Higgs rate measurements from Run 1 of the LHC for the mass of the light scalar top partner (stop) in the Minimal Supersymmetric Standard Model (MSSM). We focus on light stop masses, and we decouple the second, heavy stop and the gluino to the multi-TeV range in order to obtain a Higgs mass of ∼125 GeV. We derive lower mass limits for the light stop within various scenarios, taking into account the effects of a possibly light scalar tau partner (stau) or chargino on the Higgs rates, of additional Higgs decays to undetectable “new physics”, as well as of non-decoupling of the heavy Higgs sector. Under conservative assumptions, the stop can be as light as 123 GeV. Relaxing certain theoretical and experimental constraints, such as vacuum stability and model-dependent bounds on sparticle masses from LEP, we find that the light stop mass can be as light as 116 GeV. Our indirect limits are complementary to direct limits on the light stop mass from collider searches and have important implications for electroweak baryogenesis in the MSSM as a possible explanation for the observed matter-antimatter asymmetry of the Universe.

  7. Light stop mass limits from Higgs rate measurements in the MSSM. Is MSSM electroweak baryogenesis still alive after all?

    Energy Technology Data Exchange (ETDEWEB)

    Liebler, Stefan [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Profumo, Stefano; Stefaniak, Tim [California Univ., Santa Cruz, CA (United States). Dept. of Physics; California Univ., Santa Cruz, CA (United States). Santa Cruz Inst. for Particle Physics (SCIPP)

    2015-12-15

    We investigate the implications of the Higgs rate measurements from Run 1 of the LHC for the mass of the light scalar top partner (stop) in the Minimal Supersymmetric Standard Model (MSSM). We focus on light stop masses, and we decouple the second, heavy stop and the gluino to the multi-TeV range in order to obtain a Higgs mass of ∝125 GeV. We derive lower mass limits for the light stop within various scenarios, taking into account the effects of a possibly light scalar tau partner (stau) or chargino on the Higgs rates, of additional Higgs decays to undetectable new physics, as well as of non-decoupling of the heavy Higgs sector. Under conservative assumptions, the stop can be as light as 123 GeV. Relaxing certain theoretical and experimental constraints, such as vacuum stability and model-dependent bounds on sparticle masses from LEP, we find that the light stop mass can be as light as 116 GeV. Our indirect limits are complementary to direct limits on the light stop mass from collider searches and have important implications for electroweak baryogenesis in the MSSM as a possible explanation for the observed matter-antimatter asymmetry of the Universe.

  8. Building blocks for future detectors: Silicon test masses and 1550 nm laser light

    International Nuclear Information System (INIS)

    Schnabel, R; Britzger, M; Burmeister, O; Danzmann, K; Duck, J; Eberle, T; Friedrich, D; Luck, H; Mehmet, M; Steinlechner, S; Willke, B; Brueckner, F; Nawrodt, R

    2010-01-01

    Current interferometric gravitational wave detectors use the combination of quasi-monochromatic, continuous-wave laser light at 1064 nm and fused silica test masses at room temperature. Detectors of the third generation, such as the Einstein-Telescope, will involve a considerable sensitivity increase. The combination of 1550 nm laser radiation and crystalline silicon test masses at low temperatures might be important ingredients in order to achieve the sensitivity goal. Here we compare some properties of the fused silica and silicon test mass materials relevant for decreasing the thermal noise in future detectors as well as the recent technology achievements in the preparation of laser radiation at 1064 nm and 1550 nm relevant for decreasing the quantum noise. We conclude that silicon test masses and 1550 nm laser light have the potential to form the future building blocks of gravitational wave detection.

  9. Subset of Kappa and Lambda Germline Sequences Result in Light Chains with a Higher Molecular Mass Phenotype.

    Science.gov (United States)

    Barnidge, David R; Lundström, Susanna L; Zhang, Bo; Dasari, Surendra; Murray, David L; Zubarev, Roman A

    2015-12-04

    In our previous work, we showed that electrospray ionization of intact polyclonal kappa and lambda light chains isolated from normal serum generates two distinct, Gaussian-shaped, molecular mass distributions representing the light-chain repertoire. During the analysis of a large (>100) patient sample set, we noticed a low-intensity molecular mass distribution with a mean of approximately 24 250 Da, roughly 800 Da higher than the mean of the typical kappa molecular-mass distribution mean of 23 450 Da. We also observed distinct clones in this region that did not appear to contain any typical post-translational modifications that would account for such a large mass shift. To determine the origin of the high molecular mass clones, we performed de novo bottom-up mass spectrometry on a purified IgM monoclonal light chain that had a calculated molecular mass of 24 275.03 Da. The entire sequence of the monoclonal light chain was determined using multienzyme digestion and de novo sequence-alignment software and was found to belong to the germline allele IGKV2-30. The alignment of kappa germline sequences revealed ten IGKV2 and one IGKV4 sequences that contained additional amino acids in their CDR1 region, creating the high-molecular-mass phenotype. We also performed an alignment of lambda germline sequences, which showed additional amino acids in the CDR2 region, and the FR3 region of functional germline sequences that result in a high-molecular-mass phenotype. The work presented here illustrates the ability of mass spectrometry to provide information on the diversity of light-chain molecular mass phenotypes in circulation, which reflects the germline sequences selected by the immunoglobulin-secreting B-cell population.

  10. THE STAR FORMATION HISTORIES OF RED-SEQUENCE GALAXIES, MASS-TO-LIGHT RATIOS AND THE FUNDAMENTAL PLANE

    International Nuclear Information System (INIS)

    Allanson, Steven P.; Hudson, Michael J.; Smith, Russell J.; Lucey, John R.

    2009-01-01

    This paper addresses the challenge of understanding the typical star formation histories of red-sequence galaxies, using linestrength indices and mass-to-light ratios as complementary constraints on their stellar age distribution. We first construct simple parametric models of the star formation history that bracket a range of scenarios, and fit these models to the linestrength indices of low-redshift cluster red-sequence galaxies. For giant galaxies, we confirm the downsizing trend, i.e., the stellar populations are younger, on average, for lower σ galaxies. We find, however, that this trend flattens or reverses at σ ∼ -1 . We then compare predicted stellar mass-to-light ratios with dynamical mass-to-light ratios derived from the fundamental plane (FP), or by the SAURON group. For galaxies with σ ∼ 70 km s -1 , models with a late 'frosting' of young stars and models with exponential star formation histories have stellar mass-to-light ratios that are larger than observed dynamical mass-to-light ratios by factors of 1.7 and 1.4, respectively, and so are rejected. The single stellar population (SSP) model is consistent with the FP, and requires a modest amount of dark matter (between 20% and 30%) to account for the difference between stellar and dynamical mass-to-light ratios. A model in which star formation was 'quenched' at intermediate ages is also consistent with the observations, although in this case less dark matter is required for low mass galaxies. We also find that the contribution of stellar populations to the 'tilt' of the fundamental plane is highly dependent on the assumed star formation history: for the SSP model, the tilt of the FP is driven primarily by stellar-population effects. For a quenched model, two-thirds of the tilt is due to stellar populations and only one-third is due to dark matter or non-homology.

  11. Some Like it Hot: Linking Diffuse X-Ray Luminosity, Baryonic Mass, and Star Formation Rate in Compact Groups of Galaxies

    Science.gov (United States)

    Desjardins, Tyler D.; Gallagher, Sarah C.; Hornschemeier, Ann E.; Mulchaey, John S.; Walker, Lisa May; Brandt, Willian N.; Charlton, Jane C.; Johnson, Kelsey E.; Tzanavaris, Panayiotis

    2014-01-01

    We present an analysis of the diffuse X-ray emission in 19 compact groups (CGs) of galaxies observed with Chandra. The hottest, most X-ray luminous CGs agree well with the galaxy cluster X-ray scaling relations in L(x-T) and (L(x-sigma), even in CGs where the hot gas is associated with only the brightest galaxy. Using Spitzer photometry, we compute stellar masses and classify Hickson CGs 19, 22, 40, and 42, and RSCGs 32, 44, and 86 as fossil groups using a new definition for fossil systems that includes a broader range of masses. We find that CGs with total stellar and Hi masses are great than or equal to 10(sup (11.3) solar mass are often X-ray luminous, while lower-mass CGs only sometimes exhibit faint, localized X-ray emission. Additionally, we compare the diffuse X-ray luminosity against both the total UV and 24 micron star formation rates of each CG and optical colors of the most massive galaxy in each of the CGs. The most X-ray luminous CGs have the lowest star formation rates, likely because there is no cold gas available for star formation, either because the majority of the baryons in these CGs are in stars or the X-ray halo, or due togas stripping from the galaxies in CGs with hot halos. Finally, the optical colors that trace recent star formation histories of the most massive group galaxies do not correlate with the X-ray luminosities of the CGs, indicating that perhaps the current state of the X-ray halos is independent of the recent history of stellar mass assembly in the most massive galaxies.

  12. The radial velocity, velocity dispersion, and mass-to-light ratio of the Sculptor dwarf galaxy

    Science.gov (United States)

    Armandroff, T. E.; Da Costa, G. S.

    1986-01-01

    The radial velocity, velocity dispersion, and mass-to-light ratio for 16 K giants in the Sculptor dwarf galaxy are calculated. Spectra at the Ca II triplet are analyzed using cross-correlation techniques in order to obtain the mean velocity of + 107.4 + or - 2.0 km/s. The dimensional velocity dispersion estimated as 6.3 (+1.1, -1.3) km/s is combined with the calculated core radius and observed central surface brightness to produce a mass-to-light ratio of 6.0 in solar units. It is noted that the data indicate that the Sculptor contains a large amount of mass not found in globular clusters, and the mass is either in the form of remnant stars or low-mass dwarfs.

  13. The Speed of Light and the Hubble parameter: The Mass-Boom Effect

    International Nuclear Information System (INIS)

    Alfonso-Faus, Antonio

    2008-01-01

    We prove here that Newton's universal gravitation and momentum conservation laws together reproduce Weinberg's relation. It is shown that the Hubble parameter H must be built in this relation, or equivalently the age of the Universe t. Using a wave-to-particle interaction technique we then prove that the speed of light c decreases with cosmological time, and that c is proportional to the Hubble parameter H. We see the expansion of the Universe as a local effect due to the LAB value of the speed of light co taken as constant. We present a generalized red shift law and find a predicted acceleration for photons that agrees well with the result from Pioneer 10/11 anomalous acceleration. We finally present a cosmological model coherent with the above results that we call the Mass-Boom. It has a linear increase of mass m with time as a result of the speed of light c linear decrease with time, and the conservation of momentum mc. We obtain the baryonic mass parameter equal to the curvature parameter, Ω m Ω k , so that the model is of the type of the Einstein static, closed, finite, spherical, unlimited, with zero cosmological constant. This model is the cosmological view as seen by photons, neutrinos, tachyons etc. in contrast with the local view, the LAB reference. Neither dark matter nor dark energy is required by this model. With an initial constant speed of light during a short time we get inflation (an exponential expansion). This converts, during the inflation time, the Planck's fluctuation length of 10 -33 cm to the present size of the Universe (about 10 28 cm, constant from then on). Thereafter the Mass-Boom takes care to bring the initial values of the Universe (about 10 15 gr) to the value at the present time of about 10 55 gr

  14. New Beta-delayed Neutron Measurements in the Light-mass Fission Group

    Energy Technology Data Exchange (ETDEWEB)

    Agramunt, J. [Instituto de Física Corpuscular, CSIC-Univ. Valencia, Apdo. Correos 22085, E-46071 Valencia (Spain); García, A.R. [Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, E-28040 Madrid (Spain); Algora, A. [Instituto de Física Corpuscular, CSIC-Univ. Valencia, Apdo. Correos 22085, E-46071 Valencia (Spain); Äystö, J. [University of Jyväskylä, FI-40014 Jyväskyä (Finland); Caballero-Folch, R.; Calviño, F. [Secció d' Enginyeria Nuclear, Universitat Politécnica de Catalunya, E-08028 Barcelona (Spain); Cano-Ott, D. [Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, E-28040 Madrid (Spain); Cortés, G. [Secció d' Enginyeria Nuclear, Universitat Politécnica de Catalunya, E-08028 Barcelona (Spain); Domingo-Pardo, C. [Instituto de Física Corpuscular, CSIC-Univ. Valencia, Apdo. Correos 22085, E-46071 Valencia (Spain); Eronen, T. [University of Jyväskylä, FI-40014 Jyväskyä (Finland); Gelletly, W. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Gómez-Hornillos, M.B. [Secció d' Enginyeria Nuclear, Universitat Politécnica de Catalunya, E-08028 Barcelona (Spain); and others

    2014-06-15

    A new accurate determination of beta-delayed neutron emission probabilities from nuclei in the low mass region of the light fission group has been performed. The measurements were carried out using the BELEN 4π neutron counter at the IGISOL-JYFL mass separator in combination with a Penning trap. The new results significantly improve the uncertainties of neutron emission probabilities for {sup 91}Br, {sup 86}As, {sup 85}As, and {sup 85}Ge nuclei.

  15. Plasmonic Circuit Theory for Multiresonant Light Funneling to a Single Spatial Hot Spot.

    Science.gov (United States)

    Hughes, Tyler W; Fan, Shanhui

    2016-09-14

    We present a theoretical framework, based on plasmonic circuit models, for generating a multiresonant field intensity enhancement spectrum at a single "hot spot" in a plasmonic device. We introduce a circuit model, consisting of an array of coupled LC resonators, that directs current asymmetrically in the array, and we show that this circuit can funnel energy efficiently from each resonance to a single element. We implement the circuit model in a plasmonic nanostructure consisting of a series of metal bars of differing length, with nearest neighbor metal bars strongly coupled electromagnetically through air gaps. The resulting nanostructure resonantly traps different wavelengths of incident light in separate gap regions, yet it funnels the energy of different resonances to a common location, which is consistent with our circuit model. Our work is important for a number of applications of plasmonic nanoantennas in spectroscopy, such as in single-molecule fluorescence spectroscopy or Raman spectroscopy.

  16. Low mass SN Ia and the late light curve

    International Nuclear Information System (INIS)

    Colgate, S.A.; Fryer, C.L.

    1995-01-01

    The late bolometric light curves of type Ia supernovae, when measured accurately over several years, show an exponential decay with a 56d half-life over a drop in luminosity of 8 magnitudes (10 half-lives). The late-time light curve is thought to be governed by the decay of Co 56 , whose 77d half-life must then be modified to account for the observed decay time. Two mechanisms, both relying upon the positron fraction of the Co 56 decay, have been proposed to explain this modification. One explanation requires a large amount of emission at infra-red wavelengths where it would not be detected. The other explanation has proposed a progressive transparency or leakage of the high energy positrons (Colgate, Petschek and Kriese, 1980). For the positrons to leak out of the expanding nebula at the required rate necessary to produce the modified 56d exponential, the mass of the ejecta from a one foe (10 51 erg in kinetic energy) explosion must be small, M ejec = 0.4M circle-dot with M ejec ∝ KE 0.5 . Thus, in this leakage explanation, any reasonable estimate of the total energy of the explosion requires that the ejected mass be very much less than the Chandrasekhar mass of 1.4M circle-dot . This is very difficult to explain with the ''canonical'' Chandrasekhar-mass thermonuclear explosion that disintegrates the original white dwarf star. This result leads us to pursue alternate mechanisms of type Ia supernovae. These mechanisms include sub-Chandrasekhar thermonuclear explosions and the accretion induced collapse of Chandrasekhar mass white dwarfs. We will summarize the advantages and disadvantages of both mechanisms with considerable detail spent on our new accretion induced collapse simulations. These mechanisms lead to lower Ni 56 production and hence result in type Ia supernovae with luminosities decreased down to ∼ 50% that predicted by the ''standard'' model

  17. Hot spot in eclipsing dwarf nova IY Ursae Majoris during quiescence and normal outburst

    OpenAIRE

    Bakowska, K.; Olech, A.

    2016-01-01

    We present the analysis of hot spot brightness in light curves of the eclipsing dwarf nova IY Ursae Majoris during its normal outburst in March 2013 and in quiescence in April 2012 and in October 2015. Examination of four reconstructed light curves of the hot spot eclipses showed directly that the brightness of the hot spot changed significantly only during the outburst. The brightness of the hot spot, before and after the outburst, was on the same level. Hereby, based on the behaviour of the...

  18. Hot vacuum extraction-isotopic dilution mass spectrometry for determination of hydrogen isotopes in zircaloys

    International Nuclear Information System (INIS)

    Shi, Y.; Leeson, P.K.; Wilkin, D.; Britton, A.; Macleod, R.

    2016-01-01

    A hot vacuum extraction-isotope dilution mass spectrometry (HVE-IDMS) was studied for determination of hydrogen isotopes in zirconium metal and alloys as nuclear reactor materials. A theoretical assessment of the completeness of the extraction of hydrogen isotopes under the chosen condition was carried out based on the hydrogen and deuterium solubility data for zirconium. The optimal isotopic spiking condition for conventional IDMS was further explored for the special case IDMS where the isotope abundance of the samples is varied and non-natural. Applying the optimal conditions, the accurate IDMS determination was realized. The agreement between the measured values and the certified or prepared values of standard reference materials and homemade standard materials validate the method developed. (author)

  19. FROM HOT JUPITERS TO SUPER-EARTHS VIA ROCHE LOBE OVERFLOW

    Energy Technology Data Exchange (ETDEWEB)

    Valsecchi, Francesca; Rasio, Frederic A.; Steffen, Jason H. [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA) and Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208 (United States)

    2014-09-20

    Through tidal dissipation in a slowly spinning host star, the orbits of many hot Jupiters may decay down to the Roche limit. We expect that the ensuing mass transfer will be stable in most cases. Using detailed numerical calculations, we find that this evolution is quite rapid, potentially leading to the complete removal of the gaseous envelope in a few gigayears, and leaving behind an exposed rocky core (a {sup h}ot super-Earth{sup )}. Final orbital periods are quite sensitive to the details of the planet's mass-radius relation and to the effects of irradiation and photo-evaporation, but could be as short as a few hours or as long as several days. Our scenario predicts the existence of planets with intermediate masses ({sup h}ot Neptunes{sup )} that should be found precisely at their Roche limit and in the process of losing mass through Roche lobe overflow. The observed excess of small single-planet candidate systems observed by Kepler may also be the result of this process. If so, the properties of their host stars should track those of the hot Jupiters. Moreover, the number of systems that produced hot Jupiters could be two to three times larger than one would infer from contemporary observations.

  20. Factorization for the light-jet mass and hemisphere soft function

    Energy Technology Data Exchange (ETDEWEB)

    Becher, Thomas [Albert Einstein Center for Fundamental Physics,Institut für Theoretische Physik, Universität Bern,Sidlerstrasse 5, CH-3012 Bern (Switzerland); Pecjak, Benjamin D. [Institute for Particle Physics Phenomenology, University of Durham,DH1 3LE Durham (United Kingdom); Shao, Ding Yu [Albert Einstein Center for Fundamental Physics,Institut für Theoretische Physik, Universität Bern,Sidlerstrasse 5, CH-3012 Bern (Switzerland)

    2016-12-05

    Many collider observables suffer from non-global logarithms not captured by standard resummation techniques. Classic examples are the light-jet mass event shape in the limit of small mass and the related hemisphere soft function. We derive factorization formulas for both of these and explicitly demonstrate that they capture all logarithms present at NNLO. These formulas achieve full scale separation and provide the basis for all-order resummations. A characteristic feature of non-global observables is that the soft radiation is driven by multi-Wilson-line operators, and the ones arising here map onto those relevant for the case of narrow-cone jet cross sections. Numerically, the contributions of non-global logarithms to resummed hemisphere-mass event shapes are sizeable.

  1. Hot filament-dissociation of (CH3)3SiH and (CH3)4Si, probed by vacuum ultra violet laser time of flight mass spectroscopy.

    Science.gov (United States)

    Sharma, Ramesh C; Koshi, Mitsuo

    2006-11-01

    The decomposition of trimethylsilane and tetramethylsilane has been investigated for the first time, using hot wire (catalytic) at various temperatures. Trimethylsilane is catalytic-dissociated in these species SiH(2), CH(3)SiH, CH(3), CH(2)Si. Time of flight mass spectroscopy signal of these species are linearly increasing with increasing catalytic-temperature. Time of flight mass spectroscopy (TOFMS) signals of (CH(3))(3)SiH and photodissociated into (CH(3))(2)SiH are decreasing with increasing hot filament temperature. TOFMS signal of (CH(3))(4)Si is decreasing with increasing hot wire temperature, but (CH(3))(3)Si signal is almost constant with increasing the temperature. We calculated activation energies of dissociated species of the parental molecules for fundamental information of reaction kinetics for the first time. Catalytic-dissociation of trimethylsilane, and tetramethylsilane single source time of flight coupled single photon VUV (118 nm) photoionization collisionless radicals at temperature range of tungsten filament 800-2360 K. The study is focused to understand the fundamental information on reaction kinetics of these molecules at hot wire temperature, and processes of catalytic-chemical vapour deposition (Cat-CVD) technique which could be implemented in amorphous and crystalline SiC semiconductors thin films.

  2. ON THE FORMATION OF HOT DQ WHITE DWARFS

    International Nuclear Information System (INIS)

    Althaus, L. G.; Corsico, A. H.; Miller Bertolami, M. M.; Romero, A. D.; GarcIa-Berro, E.

    2009-01-01

    We present the first full evolutionary calculations aimed at exploring the origin of hot DQ white dwarfs. These calculations consistently cover the whole evolution from the born-again stage to the white dwarf cooling track. Our calculations provide strong support for the diffusive/convective mixing picture for the formation of hot DQs. We find that the hot DQ stage is a short-lived stage and that the range of effective temperatures where hot DQ stars are found can be accounted for by different masses of residual helium and/or different initial stellar masses. In the frame of this scenario, a correlation between the effective temperature and the surface carbon abundance in DQs should be expected, with the largest carbon abundances expected in the hottest DQs. From our calculations, we suggest that most of the hot DQs could be the cooler descendants of some PG 1159 stars characterized by He-rich envelopes markedly smaller than those predicted by the standard theory of stellar evolution. At least for one hot DQ, the high-gravity white dwarf SDSS J142625.70+575218.4, an evolutionary link between this star and the massive PG 1159 star H1504+65, is plausible.

  3. Hot-spot mix in ignition-scale inertial confinement fusion targets.

    Science.gov (United States)

    Regan, S P; Epstein, R; Hammel, B A; Suter, L J; Scott, H A; Barrios, M A; Bradley, D K; Callahan, D A; Cerjan, C; Collins, G W; Dixit, S N; Döppner, T; Edwards, M J; Farley, D R; Fournier, K B; Glenn, S; Glenzer, S H; Golovkin, I E; Haan, S W; Hamza, A; Hicks, D G; Izumi, N; Jones, O S; Kilkenny, J D; Kline, J L; Kyrala, G A; Landen, O L; Ma, T; MacFarlane, J J; MacKinnon, A J; Mancini, R C; McCrory, R L; Meezan, N B; Meyerhofer, D D; Nikroo, A; Park, H-S; Ralph, J; Remington, B A; Sangster, T C; Smalyuk, V A; Springer, P T; Town, R P J

    2013-07-26

    Mixing of plastic ablator material, doped with Cu and Ge dopants, deep into the hot spot of ignition-scale inertial confinement fusion implosions by hydrodynamic instabilities is diagnosed with x-ray spectroscopy on the National Ignition Facility. The amount of hot-spot mix mass is determined from the absolute brightness of the emergent Cu and Ge K-shell emission. The Cu and Ge dopants placed at different radial locations in the plastic ablator show the ablation-front hydrodynamic instability is primarily responsible for hot-spot mix. Low neutron yields and hot-spot mix mass between 34(-13,+50)  ng and 4000(-2970,+17 160)  ng are observed.

  4. WAVE PROPAGATION in the HOT DUCT of VHTR

    Energy Technology Data Exchange (ETDEWEB)

    Richard Schultz; Jim C. P. Liou

    2013-07-01

    In VHTR, helium from the reactor vessel is conveyed to a power conversion unit through a hot duct. In a hypothesized Depressurized Conduction Cooldown event where a rupture of the hot duct occurs, pressure waves will be initiated and reverberate in the hot duct. A numerical model is developed to quantify the transients and the helium mass flux through the rupture for such events. The flow path of the helium forms a closed loop but only the hot duct is modeled in this study. The lower plum of the reactor vessel and the steam generator are treated as specified pressure and/or temperature boundary to the hot duct. The model is based on the conservation principles of mass, momentum and energy, and on the equations of state for helium. The numerical solution is based on the method of characteristics with specified time intervals with a predictor and corrector algorithm. The rupture sub-model gives reasonable results. Transients induced by ruptures with break area equaling 20%, 10%, and 5% of the duct cross-sectional area are described.

  5. Isovector giant dipole resonance in hot rotating light nuclei in the calcium region

    International Nuclear Information System (INIS)

    Shanmugam, G.; Thiagasundaram, M.

    1989-01-01

    The isovector giant dipole resonances in hot rotating light nuclei in the calcium region are studied using a rotating anisotropic harmonic oscillator potential and a separable dipole-dipole residual interaction. The influence of temperature on the isovector giant dipole resonance is assumed to occur through the change of deformation of the average field only. Calculations are performed for the three nuclei /sup 40,42/Ca and /sup 46/Ti which have spherical, oblate, and prolate ground states, respectively, to see how their shape transitions at higher excited states affect the isovector giant resonance frequencies built on them. It is seen that, while the width fluctuations present at T = 0 vanish at T = 0.5 MeV in /sup 40,42/Ca, they persist up to T = 1.5 MeV in the case of /sup 46/Ti. This behavior brings out the role of temperature on shell effects which in turn affects the isovector giant dipole resonance widths

  6. Light hadron spectrum and quark masses from quenched lattice QCD

    International Nuclear Information System (INIS)

    Aoki, S.; Boyd, G.; Ejiri, S.; Kaneko, T.; Nagai, K.; Shanahan, H.P.; Burkhalter, R.; Iwasaki, Y.; Kanaya, K.; Ukawa, A.; Yoshie, T.; Fukugita, M.; Hashimoto, S.; Kuramashi, Y.; Okawa, M.

    2003-01-01

    We present the details of simulations for the light hadron spectrum in quenched QCD carried out on the CP-PACS parallel computer. Simulations are made with the Wilson quark action and the plaquette gauge action on lattices of size 32 3 x56-64 3 x112 at four values of lattice spacings in the range a≅0.1-0.05 fm and spatial extent L s a≅3 fm. Hadronic observables are calculated at five quark masses corresponding to m PS /m V ≅0.75-0.4, assuming the u and d quarks are degenerate, but treating the s quark separately. We find that the presence of quenched chiral singularities is supported from an analysis of the pseudoscalar meson data. The physical values of hadron masses are determined using m π , m ρ , and m K (or m φ ) as input to fix the physical scale of lattice spacing and the u, d, and s quark masses. After chiral and continuum extrapolations, the agreement of the calculated mass spectrum with experiment is at a 10% level. In comparison with the statistical accuracy of 1%-3% and systematic errors of at most 1.7% we have achieved, this demonstrates a failure of the quenched approximation for the hadron spectrum: the hyperfine splitting in the meson sector is too small, and in the baryon sector the octet masses and mass splitting of the decuplet are both smaller than experiment. Light quark masses are calculated using two definitions: the conventional one and the one based on the axial-vector Ward identity. The two results converge toward the continuum limit, yielding m ud =4.29(14) -0.79 +0.51 MeV where the first error is statistical and the second one is systematic due to chiral extrapolation. The s quark mass depends on the strange hadron mass chosen for input: m s =113.8(2.3) -2.9 +5.8 MeV from m K and m s =142.3(5.8) -0 +22.0 MeV from m φ , indicating again a failure of the quenched approximation. We obtain the scale of QCD, Λ MS (0) =219.5(5.4) MeV with m ρ used as input. An O(10%) deviation from experiment is observed in the pseudoscalar meson

  7. Sound of Dark Matter: Searching for Light Scalars with Resonant-Mass Detectors.

    Science.gov (United States)

    Arvanitaki, Asimina; Dimopoulos, Savas; Van Tilburg, Ken

    2016-01-22

    The fine-structure constant and the electron mass in string theory are determined by the values of scalar fields called moduli. If the dark matter takes on the form of such a light modulus, it oscillates with a frequency equal to its mass and an amplitude determined by the local dark-matter density. This translates into an oscillation of the size of a solid that can be observed by resonant-mass antennas. Existing and planned experiments, combined with a dedicated resonant-mass detector proposed in this Letter, can probe dark-matter moduli with frequencies between 1 kHz and 1 GHz, with much better sensitivity than searches for fifth forces.

  8. Dark matter contraction and stellar-mass-to-light ratio gradients in massive early-type galaxies

    Science.gov (United States)

    Oldham, Lindsay J.; Auger, Matthew W.

    2018-05-01

    We present models for the dark and luminous mass structure of 12 strong lensing early-type galaxies. We combine pixel-based modelling of multiband Hubble Space Telescope imaging with Jeans modelling of kinematics obtained from Keck/ESI spectra to disentangle the dark and luminous contributions to the mass. Assuming a generalised NFW (gNFW) profile for the dark matter halo and a spatially constant stellar-mass-to-light ratio ϒ⋆ for the baryonic mass, we infer distributions for ϒ⋆ consistent with initial mass functions (IMFs) that are heavier than the Milky Way's (with a global mean mismatch parameter relative to a Chabrier IMF μαc = 1.80 ± 0.14) and halo inner density slopes that span a large range but are generally cuspier than the dark-matter-only prediction (μ _{γ ^' }} = 2.01_{-0.22}^{+0.19}). We investigate possible reasons for overestimating the halo slope, including the neglect of spatially varying stellar-mass-to-light ratios and/or stellar orbital anisotropy, and find that a quarter of the systems prefer radially declining stellar-mass-to-light ratio gradients, but that the overall effect on our inference on the halo slope is small. We suggest a coherent explanation of these results in the context of inside-out galaxy growth, and that the relative importance of different baryonic processes in shaping the dark halo may depend on halo environment.

  9. The influence of mass transfer, velocity and mechanical stress on the growth of coating in hot water

    International Nuclear Information System (INIS)

    Heimsch, R.; Hegele, E.; Frau, B.

    1977-01-01

    Within the scope of the research programme of the special research range 157 'Thermal Power Plant' at the university of Stuttgart, the formation, the growth and the characteristics of the magnetite layer (Fe 3 O 4 ) in steam generator pipes, in the hot water phase will be analysed. In the Grosskraftwerk Mannheim AG a test plant was installed for that purpose, which operates at present in circulating operation at p = 250 bars and t = 340 0 C. For the Fe 3 O 4 formation important parameters, temperature, pH-value, Fe-, O 2 -, H 2 -content, electrical conductivity and redox potential will be controlled. By hot water oxidation - this is the range on which our research is concentrated at present, a double layer epitactical and topotactical of Fe 3 O 4 is formed. One of the undesired layer types is the so-called 'Ripple-rafflers' of the epitactical layer, which results in an extensive increase of pressure loss in the evaporator, and which requires cleaning of the evaporator. Referred to the entire system, the pressure loss increase can be up to 30%. During the report period, the influece of speed, mass flux and mechanical stress on the layer growth in hot water, especially on the morphology of the protective layers have been researched. The achieved results will be described in this lecture. (orig.) [de

  10. THE AKARI 2.5-5.0 μm SPECTRAL ATLAS OF TYPE-1 ACTIVE GALACTIC NUCLEI: BLACK HOLE MASS ESTIMATOR, LINE RATIO, AND HOT DUST TEMPERATURE

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dohyeong; Im, Myungshin; Kim, Ji Hoon; Jun, Hyunsung David; Lee, Seong-Kook [Center for the Exploration of the Origin of the Universe (CEOU), Astronomy Program, Department of Physics and Astronomy, Seoul National University, Shillim-Dong, Kwanak-Gu, Seoul 151-742 (Korea, Republic of); Woo, Jong-Hak; Lee, Hyung Mok; Lee, Myung Gyoon [Astronomy Program, Department of Physics and Astronomy, Seoul National University, Shillim-Dong, Kwanak-Gu, Seoul 151-742 (Korea, Republic of); Nakagawa, Takao; Matsuhara, Hideo; Wada, Takehiko; Takagi, Toshinobu [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa 252-5210 (Japan); Oyabu, Shinki [Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8602 (Japan); Ohyama, Youichi, E-mail: dohyeong@astro.snu.ac.kr, E-mail: mim@astro.snu.ac.kr [Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 106, Taiwan (China)

    2015-01-01

    We present 2.5-5.0 μm spectra of 83 nearby (0.002 < z < 0.48) and bright (K < 14 mag) type-1 active galactic nuclei (AGNs) taken with the Infrared Camera on board AKARI. The 2.5-5.0 μm spectral region contains emission lines such as Brβ (2.63 μm), Brα (4.05 μm), and polycyclic aromatic hydrocarbons (3.3 μm), which can be used for studying the black hole (BH) masses and star formation activity in the host galaxies of AGNs. The spectral region also suffers less dust extinction than in the ultra violet (UV) or optical wavelengths, which may provide an unobscured view of dusty AGNs. Our sample is selected from bright quasar surveys of Palomar-Green and SNUQSO, and AGNs with reverberation-mapped BH masses from Peterson et al. Using 11 AGNs with reliable detection of Brackett lines, we derive the Brackett-line-based BH mass estimators. We also find that the observed Brackett line ratios can be explained with the commonly adopted physical conditions of the broad line region. Moreover, we fit the hot and warm dust components of the dust torus by adding photometric data of SDSS, 2MASS, WISE, and ISO to the AKARI spectra, finding hot and warm dust temperatures of ∼1100 K and ∼220 K, respectively, rather than the commonly cited hot dust temperature of 1500 K.

  11. On QCD sum rules of the Laplace transform type and light quark masses

    International Nuclear Information System (INIS)

    Narison, S.

    1981-04-01

    We discuss the relation between the usual dispersion relation sum rules and the Laplace transform type sum rules in quantum chromodynamics. Two specific examples corresponding to the S-coupling constant sum rule and the light quark masses sum rules are considered. An interpretation, within QCD, of Leutwyler's formula for the current algebra quark masses is also given

  12. Effects of Dim Light at Night on Food Intake and Body Mass in Developing Mice.

    Science.gov (United States)

    Cissé, Yasmine M; Peng, Juan; Nelson, Randy J

    2017-01-01

    Appropriately timed light is critical for circadian organization; exposure to dim light at night (dLAN) disrupts temporal organization of endogenous biological timing. Exposure to dLAN in adult mice is associated with elevated body mass and changes in metabolism putatively driven by voluntary changes in the time of food intake. We predicted that exposure of young mice to LAN could affect adult metabolic function. At 3 weeks (Experiment 1) or 5 weeks (Experiment 2) of age, mice were either maintained in standard light-dark (DARK) cycles or exposed to nightly dLAN (5 lux). In the first two experiments, food intake and locomotor activity were assessed after 4 weeks and a glucose tolerance test was administered after 6 weeks in experimental lighting conditions. In Experiment 3, tissues were collected around the clock at 6 h intervals to investigate rhythmic hepatic clock gene expression in mice exposed to dLAN from 3 or 5 weeks of age. Male and female mice exposed to dLAN beginning at 3 weeks of age displayed similar growth rates and body mass to DARK-reared offspring, despite increasing day-time food intake. Exposure to dLAN beginning at 5 weeks of age increased body mass and daytime food intake in male, but not female, mice. Consistent with the body mass phenotype, clock gene expression was unaltered in the liver. In contrast to adults, dLAN exposure during the development of the peripheral circadian system has sex- and development-dependent effects on body mass gain.

  13. Effects of Dim Light at Night on Food Intake and Body Mass in Developing Mice

    Directory of Open Access Journals (Sweden)

    Yasmine M. Cissé

    2017-05-01

    Full Text Available Appropriately timed light is critical for circadian organization; exposure to dim light at night (dLAN disrupts temporal organization of endogenous biological timing. Exposure to dLAN in adult mice is associated with elevated body mass and changes in metabolism putatively driven by voluntary changes in the time of food intake. We predicted that exposure of young mice to LAN could affect adult metabolic function. At 3 weeks (Experiment 1 or 5 weeks (Experiment 2 of age, mice were either maintained in standard light-dark (DARK cycles or exposed to nightly dLAN (5 lux. In the first two experiments, food intake and locomotor activity were assessed after 4 weeks and a glucose tolerance test was administered after 6 weeks in experimental lighting conditions. In Experiment 3, tissues were collected around the clock at 6 h intervals to investigate rhythmic hepatic clock gene expression in mice exposed to dLAN from 3 or 5 weeks of age. Male and female mice exposed to dLAN beginning at 3 weeks of age displayed similar growth rates and body mass to DARK-reared offspring, despite increasing day-time food intake. Exposure to dLAN beginning at 5 weeks of age increased body mass and daytime food intake in male, but not female, mice. Consistent with the body mass phenotype, clock gene expression was unaltered in the liver. In contrast to adults, dLAN exposure during the development of the peripheral circadian system has sex- and development-dependent effects on body mass gain.

  14. The X-ray signature of solar coronal mass

    Science.gov (United States)

    Harrison, R. A.; Waggett, P. W.; Bentley, R. D.; Phillips, K. J. H.; Bruner, M.

    1985-01-01

    The coronal response to six solar X-ray flares has been investigated. At a time coincident with the projected onset of the white-light coronal mass ejection associated with each flare, there is a small, discrete soft X-ray enhancement. These enhancements (precursors) precede by typically about 20 m the impulsive phase of the solar flare which is dominant by the time the coronal mass ejection has reached an altitude above 0.5 solar radii. Motions of hot X-ray emitting plasma, during the precursors, which may well be a signature of the mass ejection onsets, are identified. Further investigations have also revealed a second class of X-ray coronal transient, during the main phase of the flare. These appear to be associated with magnetic reconnection above post-flare loop systems.

  15. Light quark masses from exclusive tau decays

    International Nuclear Information System (INIS)

    Stern, J.; Knecht, M.; Fuchs, N.H.

    1993-01-01

    A method of indirect measurement of the light quark running mass m-circumflex = (m d + m u )/2 is elaborated in detail. It is based on measuring 1%-level azimuthal angular asymmetries in the decay τ→ν τ + 3π. The latter are then used in QCD sum rules to obtain experimental lower bounds for m-circumflex. For a sample of 2.5 * 10 5 τ→ν τ + 3π decays free of background, the resulting statistical error in the bound for m-circumflex is estimated to be 1 MeV, i.e., comparable to the systematic error due to the use of QCD sum rules. (authors) 22 refs., 7 figs., 1 tab

  16. Radiative corrections to light neutrino masses in low scale type I seesaw scenarios and neutrinoless double beta decay

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Pavon, J. [SISSA and INFN - sezione di Trieste, via Bonomea 265, 34136 Trieste (Italy); Molinaro, E. [CP-Origins and Danish Institute for Advanced Study, University of Southern Denmark,Campusvej 55, DK-5230 Odense M (Denmark); Petcov, S.T. [SISSA and INFN - sezione di Trieste, via Bonomea 265, 34136 Trieste (Italy); Kavli IPMU (WPI), University of Tokyo, 5-1-5 Kashiwanoha, 277-8583 Kashiwa (Japan)

    2015-11-05

    We perform a detailed analysis of the one-loop corrections to the light neutrino mass matrix within low scale type I seesaw extensions of the Standard Model and their implications in experimental searches for neutrinoless double beta decay. We show that a sizable contribution to the effective Majorana neutrino mass from the exchange of heavy Majorana neutrinos is always possible, provided one requires a fine-tuned cancellation between the tree-level and one-loop contribution to the light neutrino masses. We quantify the level of fine-tuning as a function of the seesaw parameters and introduce a generalisation of the Casas-Ibarra parametrization of the neutrino Yukawa matrix, which easily allows to include the one-loop corrections to the light neutrino masses.

  17. Pre-cometary ice composition from hot core chemistry.

    Science.gov (United States)

    Tornow, Carmen; Kührt, Ekkehard; Motschmann, Uwe

    2005-10-01

    Pre-cometary ice located around star-forming regions contains molecules that are pre-biotic compounds or pre-biotic precursors. Molecular line surveys of hot cores provide information on the composition of the ice since it sublimates near these sites. We have combined a hydrostatic hot core model with a complex network of chemical reactions to calculate the time-dependent abundances of molecules, ions, and radicals. The model considers the interaction between the ice and gas phase. It is applied to the Orion hot core where high-mass star formation occurs, and to the solar-mass binary protostar system IRAS 16293-2422. Our calculations show that at the end of the hot core phase both star-forming sites produce the same prebiotic CN-bearing molecules. However, in the Orion hot core these molecules are formed in larger abundances. A comparison of the calculated values with the abundances derived from the observed line data requires a chemically unprocessed molecular cloud as the initial state of hot core evolution. Thus, it appears that these objects are formed at a much younger cloud stage than previously thought. This implies that the ice phase of the young clouds does not contain CN-bearing molecules in large abundances before the hot core has been formed. The pre-biotic molecules synthesized in hot cores cause a chemical enrichment in the gas phase and in the pre-cometary ice. This enrichment is thought to be an important extraterrestrial aspect of the formation of life on Earth and elsewhere.

  18. Mass estimates from optical-light curves for binary X-ray sources

    International Nuclear Information System (INIS)

    Avni, Y.

    1978-01-01

    The small amplitude variations with orbital phase of the optical light from X-ray binaries are caused by the changing geometrical aspect of the primary as seen by a fixed observer. The shape and the amplitude of the light curve depends on the stellar masses and on the orbital elements. The light curve can, therefore, be used to determine, or set limits on, the parameters of the binary system. A self-consistent procedure for the calculation of the light curve can be formulated if the primary is formulated if the primary is uniformly rotating at an angular velocity equal to the angular velocity of its orbital revolution in a circular orbit, and if the primary is in a hydrostatic and radiative equilibrium in the co-rotating frame. When the primary is further approximated to be centrally condensed, the above set of assumptions is called the standard picture. The standard picture is described, its validity discussed and its application to various systems reviewed. (C.F.)

  19. Surface-Plasmon-Driven Hot Electron Photochemistry.

    Science.gov (United States)

    Zhang, Yuchao; He, Shuai; Guo, Wenxiao; Hu, Yue; Huang, Jiawei; Mulcahy, Justin R; Wei, Wei David

    2017-11-30

    Visible-light-driven photochemistry has continued to attract heightened interest due to its capacity to efficiently harvest solar energy and its potential to solve the global energy crisis. Plasmonic nanostructures boast broadly tunable optical properties coupled with catalytically active surfaces that offer a unique opportunity for solar photochemistry. Resonant optical excitation of surface plasmons produces energetic hot electrons that can be collected to facilitate chemical reactions. This review sums up recent theoretical and experimental approaches for understanding the underlying photophysical processes in hot electron generation and discusses various electron-transfer models on both plasmonic metal nanostructures and plasmonic metal/semiconductor heterostructures. Following that are highlights of recent examples of plasmon-driven hot electron photochemical reactions within the context of both cases. The review concludes with a discussion about the remaining challenges in the field and future opportunities for addressing the low reaction efficiencies in hot-electron-induced photochemistry.

  20. The ATLAS(3D) project - XX. Mass-size and mass-Sigma distributions of early-type galaxies : bulge fraction drives kinematics, mass-to-light ratio, molecular gas fraction and stellar initial mass function

    NARCIS (Netherlands)

    Cappellari, Michele; McDermid, Richard M.; Alatalo, Katherine; Blitz, Leo; Bois, Maxime; Bournaud, Frederic; Bureau, M.; Crocker, Alison F.; Davies, Roger L.; Davis, Timothy A.; de Zeeuw, P. T.; Duc, Pierre-Alain; Emsellem, Eric; Khochfar, Sadegh; Krajnovic, Davor; Kuntschner, Harald; Morganti, Raffaella; Naab, Thorsten; Oosterloo, Tom; Sarzi, Marc; Scott, Nicholas; Serra, Paolo; Weijmans, Anne-Marie; Young, Lisa M.

    2013-01-01

    In the companion Paper XV of this series, we derive accurate total mass-to-light ratios (M/L)(JAM) approximate to (M/L)(r = R-e) within a sphere of radius r = R-e centred on the galaxy, as well as stellar (M/L)(stars) (with the dark matter removed) for the volume-limited and nearly mass-selected

  1. Carotenoid deactivation in an artificial light-harvesting complex via a vibrationally hot ground state

    International Nuclear Information System (INIS)

    Savolainen, Janne; Buckup, Tiago; Hauer, Juergen; Jafarpour, Aliakbar; Serrat, Carles; Motzkus, Marcus; Herek, Jennifer L.

    2009-01-01

    Ultrafast relaxation of a carotenoid in an artificial light-harvesting complex has been studied by transient absorption spectroscopy. The transient signal amplitudes at several wavelengths as well as the amplitudes of the underlying species associated spectra (SAS) are analysed for several excitation energies ranging over more than two orders of magnitude (10 nJ/pulse up to 3000 nJ/pulse). Our analysis shows that the contribution from the so-called S* signal on the long-wavelength side of the first allowed S 0 → S 2 transition has a markedly different excitation energy dependence and saturation behaviour than the electronic excited state S 1 . These observations are modelled and explained in terms of a two-photon excitation of a vibrationally hot ground state via an impulsive stimulated Raman scattering (ISRS). The experimental observations of the varying pulse energy dependencies of different excited state species are supported by an analysis based on a density-matrix formalism

  2. Perturbative determination of mass-dependent renormalization and improvement coefficients for the heavy-light vector and axial-vector currents with relativistic heavy and domain-wall light quarks

    International Nuclear Information System (INIS)

    Yamada, Norikazu; Aoki, Sinya; Kuramashi, Yoshinobu

    2005-01-01

    We determine the mass-dependent renormalization as well as improvement coefficients for the heavy-light vector and axial-vector currents consisting of the relativistic heavy and the domain-wall light quarks through the standard matching procedure. The calculation is carried out perturbatively at the one-loop level to remove the systematic error of O(α s (am Q ) n ap) as well as O(α s (am Q ) n ) (n>=0), where p is a typical momentum scale in the heavy-light system. We point out that renormalization and improvement coefficients of the heavy-light vector current agree with those of the axial-vector current, thanks to the exact chiral symmetry for the light quark. The results obtained with three different gauge actions, plaquette, Iwasaki and DBW2, are presented as a function of heavy quark mass and domain-wall height

  3. Testing a class of non-Kerr metrics with hot spots orbiting SgrA*

    International Nuclear Information System (INIS)

    Liu, Dan; Li, Zilong; Bambi, Cosimo

    2015-01-01

    SgrA*, the supermassive black hole candidate at the Galactic Center, exhibits flares in the X-ray, NIR, and sub-mm bands that may be interpreted within a hot spot model. Light curves and images of hot spots orbiting a black hole are affected by a number of special and general relativistic effects, and they can be potentially used to check whether the object is a Kerr black hole of general relativity. However, in a previous study we have shown that the relativistic features are usually subdominant with respect to the background noise and the model-dependent properties of the hot spot, and eventually it is at most possible to estimate the frequency of the innermost stable circular orbit. In this case, tests of the Kerr metric are only possible in combination with other measurements. In the present work, we consider a class of non-Kerr spacetimes in which the hot spot orbit may be outside the equatorial plane. These metrics are difficult to constrain from the study of accretion disks and indeed current X-ray observations of stellar-mass and supermassive black hole candidates cannot put interesting bounds. Here we show that near future observations of SgrA* may do it. If the hot spot is sufficiently close to the massive object, the image affected by Doppler blueshift is brighter than the other one and this provides a specific observational signature in the hot spot's centroid track. We conclude that accurate astrometric observations of SgrA* with an instrument like GRAVITY should be able to test this class of metrics, except in the more unlikely case of a small viewing angle

  4. Long-lived hot-carrier light emission and large blue shift in formamidinium tin triiodide perovskites

    NARCIS (Netherlands)

    Fang, Hong-Hua; Adjokatse, Sampson; Shao, Shuyan; Even, Jacky; Loi, Maria Antonietta

    2018-01-01

    A long-lived hot carrier population is critical in order to develop working hot carrier photovoltaic devices with efficiencies exceeding the Shockley-Queisser limit. Here, we report photoluminescence from hot-carriers with unexpectedly long lifetime (a few ns) in formamidinium tin triiodide. An

  5. Decay of hot nuclei produced by relativistic light ions

    International Nuclear Information System (INIS)

    Karnaukhov, V.A.; Avdeev, S.P.; Kuznetsov, V.D.

    1995-01-01

    In collisions of light relativistic projectiles (p, 4 He) with heavy nuclei (Au) very excited target spectators are created, which decay via multiple emission of intermediate mass fragments. It was found that the mean IMF multiplicities are equal (within 15%) to 2.0, 2.6 and 3.0 at proton energies 2.16, 3.6 and 8.1 GeV respectively. These values are comparable with those obtained with heavy ions in the same beam energy range. This is considered to indicate that this observable is not sensitive to the collision dynamics and is determined by the phase space factor. IMF energy spectra are described by the statistical model of multifragmentation neglecting dynamics of the expansion stage before the break up. The expansion velocity is estimated to be ≤ 0.02 c. The mean lifetime of a fragmentating system is found to be ≤ 75 fm/c from IMF-IMF-angular correlations for 4 He (14.6 GeV) +Au collisions. The results support a scenario of true 'thermal' multifragmentation. 26 refs., 10 figs., 1 tab

  6. The mass of the black hole in 1A 0620-00, revisiting the ellipsoidal light curve modelling

    Science.gov (United States)

    van Grunsven, Theo F. J.; Jonker, Peter G.; Verbunt, Frank W. M.; Robinson, Edward L.

    2017-12-01

    The mass distribution of stellar-mass black holes can provide important clues to supernova modelling, but observationally it is still ill constrained. Therefore, it is of importance to make black hole mass measurements as accurate as possible. The X-ray transient 1A 0620-00 is well studied, with a published black hole mass of 6.61 ± 0.25 M⊙, based on an orbital inclination i of 51.0° ± 0.9°. This was obtained by Cantrell et al. (2010) as an average of independent fits to V-, I- and H-band light curves. In this work, we perform an independent check on the value of i by re-analysing existing YALO/SMARTS V-, I- and H-band photometry, using different modelling software and fitting strategy. Performing a fit to the three light curves simultaneously, we obtain a value for i of 54.1° ± 1.1°, resulting in a black hole mass of 5.86 ± 0.24 M⊙. Applying the same model to the light curves individually, we obtain 58.2° ± 1.9°, 53.6° ± 1.6° and 50.5° ± 2.2° for V-, I- and H-band, respectively, where the differences in best-fitting i are caused by the contribution of the residual accretion disc light in the three different bands. We conclude that the mass determination of this black hole may still be subject to systematic effects exceeding the statistical uncertainty. Obtaining more accurate masses would be greatly helped by continuous phase-resolved spectroscopic observations simultaneous with photometry.

  7. Acute dim light at night increases body mass, alters metabolism, and shifts core body temperature circadian rhythms.

    Science.gov (United States)

    Borniger, Jeremy C; Maurya, Santosh K; Periasamy, Muthu; Nelson, Randy J

    2014-10-01

    The circadian system is primarily entrained by the ambient light environment and is fundamentally linked to metabolism. Mounting evidence suggests a causal relationship among aberrant light exposure, shift work, and metabolic disease. Previous research has demonstrated deleterious metabolic phenotypes elicited by chronic (>4 weeks) exposure to dim light at night (DLAN) (∼ 5 lux). However, the metabolic effects of short-term (dim light would gain more body mass, alter whole body metabolism, and display altered body temperature (Tb) and activity rhythms compared to mice maintained in dark nights. Our data largely support these predictions; DLAN mice gained significantly more mass, reduced whole body energy expenditure, increased carbohydrate over fat oxidation, and altered temperature circadian rhythms. Importantly, these alterations occurred despite similar activity locomotor levels (and rhythms) and total food intake between groups. Peripheral clocks are potently entrained by body temperature rhythms, and the deregulation of body temperature we observed may contribute to metabolic problems due to "internal desynchrony" between the central circadian oscillator and temperature sensitive peripheral clocks. We conclude that even relatively short-term exposure to low levels of nighttime light can influence metabolism to increase mass gain.

  8. Mass loss, levitation, accretion, and the sharp-lined features in hot white dwarfs

    International Nuclear Information System (INIS)

    Bruhweiler, F.C.; Kondo, Y.

    1983-01-01

    We have studied eight white dwarfs, seven DA and one He-rich types, observed at a high resolution (lambda/Δlambdaroughly-equal10 4 ) with the International Ultraviolet Explorer (IUE). Of the seven DA white dwarfs, three show spectral signatures of ionized heavy elements, such as Si II, SI III, C IV, Si IV, and N V, arising in the immediate environment of these stars. The shortward-shifted lines in two (G191--B2B and 2111+49) of the three DA types showing metallic lines are tentatively interpreted as an indication of mass loss from these stars. The He-rich white dwarf shows the features due to C cV and He II, which also arise in the immediate environment of that star. Although the statistical sample presented here is limited, we tentatively suggest a temperature and effective gravity range (T/sub eff/> or approx. =20,000 K and log (g) < or approx. =8.0) in DA white dwarfs within which metallic lines are present either in the photosphere or in the halo of the stars. We examine the physical processes relevant to the appearance of such metallic lines. We tentatively propose that radiative levitation can explain the appearance of the observed lines in the hot DA white dwarfs, although the role of radiation forces in mass loss is not clear

  9. Sterile neutrinos with eV masses in cosmology — How disfavoured exactly?

    International Nuclear Information System (INIS)

    Hamann, Jan; Hannestad, Steen; Raffelt, Georg G.; Wong, Yvonne Y.Y.

    2011-01-01

    We study cosmological models that contain sterile neutrinos with eV-range masses as suggested by reactor and short-baseline oscillation data. We confront these models with both precision cosmological data (probing the CMB decoupling epoch) and light-element abundances (probing the BBN epoch). In the minimal ΛCDM model, such sterile neutrinos are strongly disfavoured by current data because they contribute too much hot dark matter. However, if the cosmological framework is extended to include also additional relativistic degrees of freedom beyond the three standard neutrinos and the putative sterile neutrinos, then the hot dark matter constraint on the sterile states is considerably relaxed. A further improvement is achieved by allowing a dark energy equation of state parameter w e degeneracy. Any model containing eV-mass sterile neutrinos implies also strong modifications of other cosmological parameters. Notably, the inferred cold dark matter density can shift up by 20–75% relative to the standard ΛCDM value

  10. HQE parameters from unquenched lattice data on pseudoscalar and vector heavy-light meson masses

    Science.gov (United States)

    Gambino, Paolo; Melis, Aurora; Simula, Silvano

    2018-03-01

    We present a new lattice determination of some of the parameters appearing both in the Operator Product Expansion (OPE) analysis of the inclusive semileptonic B-meson decays and in the Heavy Quark Expansion (HQE) of the pseudoscalar (PS) and vector (V) heavy-light meson masses. We perform a lattice QCD (LQCD) computation of PS and V heavy-light meson masses for heavy-quark masses mh in the range from mcphys to ≃ 4mbphys. We employed the Nf = 2 + 1 + 1 gauge configurations of the European Twisted Mass Collaboration (ETMC) at three values of the lattice spacing a ≃ (0.062,0.082,0.089) fm with pion masses in the range Mπ ≃ (210 - 450) MeV. The heavy-quark mass is simulated directly on the lattice up to ≃ 3mcphys. The interpolation to the physical mbphys is performed using the ETMC ratio method and adopting the kinetic mass scheme. We obtain mbkin (1 GeV) = 4.61(20) GeV (m̅b(m̅b) = 4.26(18) GeV in the MS scheme). The lattice data are analyzed in terms of the HQE and the matrix elements of dimension-4 and dimension-5 operators are extracted with good precision, namely: Λ¯ = 0.552(26) GeV, μπ2 = 0.321(32) GeV2 and μG2(mb) = 0.253(25)GeV2. The data also allow for an estimate of the dimension-6 operator matrix elements.

  11. An Integrated Hot-Stage Microscope-Direct Analysis in Real Time-Mass Spectrometry System for Studying the Thermal Behavior of Materials.

    Science.gov (United States)

    Ashton, Gage P; Harding, Lindsay P; Parkes, Gareth M B

    2017-12-19

    This paper describes a new analytical instrument that combines a precisely temperature-controlled hot-stage with digital microscopy and Direct Analysis in Real Time-mass spectrometry (DART-MS) detection. The novelty of the instrument lies in its ability to monitor processes as a function of temperature through the simultaneous recording of images, quantitative color changes, and mass spectra. The capability of the instrument was demonstrated through successful application to four very varied systems including profiling an organic reaction, decomposition of silicone polymers, and the desorption of rhodamine B from an alumina surface. The multidimensional, real-time analytical data provided by this instrument allow for a much greater insight into thermal processes than could be achieved previously.

  12. Objective and subjective measures of exercise intensity during thermo-neutral and hot yoga.

    Science.gov (United States)

    Boyd, Corinne N; Lannan, Stephanie M; Zuhl, Micah N; Mora-Rodriguez, Ricardo; Nelson, Rachael K

    2018-04-01

    While hot yoga has gained enormous popularity in recent years, owing in part to increased environmental challenge associated with exercise in the heat, it is not clear whether hot yoga is more vigorous than thermo-neutral yoga. Therefore, the aim of this study was to determine objective and subjective measures of exercise intensity during constant intensity yoga in a hot and thermo-neutral environment. Using a randomized, crossover design, 14 participants completed 2 identical ∼20-min yoga sessions in a hot (35.3 ± 0.8 °C; humidity: 20.5% ± 1.4%) and thermo-neutral (22.1 ± 0.2 °C; humidity: 27.8% ± 1.6%) environment. Oxygen consumption and heart rate (HR) were recorded as objective measures (percentage of maximal oxygen consumption and percentage of maximal HR (%HRmax)) and rating of perceived exertion (RPE) was recorded as a subjective measure of exercise intensity. There was no difference in exercise intensity based on percentage of maximal oxygen consumption during hot versus thermo-neutral yoga (30.9% ± 2.3% vs. 30.5% ± 1.8%, p = 0.68). However, exercise intensity was significantly higher during hot versus thermo-neutral yoga based on %HRmax (67.0% ± 2.3% vs. 60.8% ± 1.9%, p = 0.01) and RPE (12 ± 1 vs. 11 ± 1, p = 0.04). According to established exercise intensities, hot yoga was classified as light-intensity exercise based on percentage of maximal oxygen consumption but moderate-intensity exercise based on %HRmax and RPE while thermo-neutral yoga was classified as light-intensity exercise based on percentage of maximal oxygen uptake, %HRmax, and RPE. Despite the added hemodynamic stress and perception that yoga is more strenuous in a hot environment, we observed similar oxygen consumption during hot versus thermo-neutral yoga, classifying both exercise modalities as light-intensity exercise.

  13. KOI 1224: A FOURTH BLOATED HOT WHITE DWARF COMPANION FOUND WITH KEPLER

    International Nuclear Information System (INIS)

    Breton, R. P.; Van Kerkwijk, M. H.; Rappaport, S. A.; Carter, J. A.

    2012-01-01

    We present an analysis and interpretation of the Kepler binary system KOI 1224. This is the fourth binary found with Kepler that consists of a thermally bloated, hot white dwarf in a close orbit with a more or less normal star of spectral class A or F. As we show, KOI 1224 contains a white dwarf with T eff = 14, 700 ± 1000 K, mass = 0.22 ± 0.02 M ☉ , and radius = 0.103 ± 0.002 R ☉ , and an F-star companion of mass 1.59 ± 0.06 M ☉ that is somewhat beyond its terminal-age main sequence. The orbital period is quite short at 2.69802 days. The ingredients that are used in the analysis are the Kepler binary light curve, including the detection of the Doppler boosting effect; the NUV and FUV fluxes from the GALEX images of this object; an estimate of the spectral type of the F-star companion; and evolutionary models of the companion designed to match its effective temperature and mean density. The light curve is modeled with a new code named Icarus which we describe in detail. Its features include the full treatment of orbital phase-resolved spectroscopy, Doppler boosting, irradiation effects, and transits/eclipses, which are particularly suited to irradiated eclipsing binaries. We interpret the KOI 1224 system in terms of its likely evolutionary history. We infer that this type of system, containing a bloated hot white dwarf, is the direct descendant of an Algol-type binary. In spite of this basic understanding of the origin of KOI 1224, we discuss a number of problems associated with producing a system with an orbital period this short.

  14. Photoionization mass spectrometer for studies of flame chemistry with a synchrotron light source

    International Nuclear Information System (INIS)

    Cool, Terrill A.; McIlroy, Andrew; Qi, Fei; Westmoreland, Phillip R.; Poisson, Lionel; Peterka, Darcy S.; Ahmed, Musahid

    2005-01-01

    A flame-sampling molecular-beam photoionization mass spectrometer, recently designed and constructed for use with a synchrotron-radiation light source, provides significant improvements over previous molecular-beam mass spectrometers that have employed either electron-impact ionization or vacuum ultraviolet laser photoionization. These include superior signal-to-noise ratio, soft ionization, and photon energies easily and precisely tunable [E/ΔE(FWHM)≅250-400] over the 7.8-17-eV range required for quantitative measurements of the concentrations and isomeric compositions of flame species. Mass resolution of the time-of-flight mass spectrometer is m/Δm=400 and sensitivity reaches ppm levels. The design of the instrument and its advantages for studies of flame chemistry are discussed

  15. Plasmonic photocatalytic reactions enhanced by hot electrons in a one-dimensional quantum well

    Directory of Open Access Journals (Sweden)

    H. J. Huang

    2015-11-01

    Full Text Available The plasmonic endothermic oxidation of ammonium ions in a spinning disk reactor resulted in light energy transformation through quantum hot charge carriers (QHC, or quantum hot electrons, during a chemical reaction. It is demonstrated with a simple model that light of various intensities enhance the chemical oxidization of ammonium ions in water. It was further observed that light illumination, which induces the formation of plasmons on a platinum (Pt thin film, provided higher processing efficiency compared with the reaction on a bare glass disk. These induced plasmons generate quantum hot electrons with increasing momentum and energy in the one-dimensional quantum well of a Pt thin film. The energy carried by the quantum hot electrons provided the energy needed to catalyze the chemical reaction. The results indicate that one-dimensional confinement in spherical coordinates (i.e., nanoparticles is not necessary to provide an extra excited state for QHC generation; an 8 nm Pt thin film for one-dimensional confinement in Cartesian coordinates can also provide the extra excited state for the generation of QHC.

  16. CLS 2+1 flavor simulations at physical light- and strange-quark masses

    International Nuclear Information System (INIS)

    Mohler, Daniel; Schaefer, Stefan; Simeth, Jakob

    2017-12-01

    We report recent efforts by CLS to generate an ensemble with physical light- and strange-quark masses in a lattice volume of 192 x 96 3 at β=3.55 corresponding to a lattice spacing of 0.064 fm. This ensemble is being generated as part of the CLS 2+1 flavor effort with improved Wilson fermions. Our simulations currently cover 5 lattice spacings ranging from 0.039 fm to 0.086 fm at various pion masses along chiral trajectories with either the sum of the quark masses kept fixed, or with the strange-quark mass at the physical value. The current status of simulations is briefly reviewed, including a short discussion of measured autocorrelation times and of the main features of the simulations. We then proceed to discuss the thermalization strategy employed for the generation of the physical quark-mass ensemble and present first results for some simple observables. Challenges encountered in the simulation are highlighted.

  17. CLS 2+1 flavor simulations at physical light- and strange-quark masses

    Energy Technology Data Exchange (ETDEWEB)

    Mohler, Daniel [Helmholtz-Institut Mainz (Germany); Mainz Univ. (Germany); Schaefer, Stefan [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Simeth, Jakob [Regensburg Univ. (Germany). Inst. fuer Theoretische Physik

    2017-12-15

    We report recent efforts by CLS to generate an ensemble with physical light- and strange-quark masses in a lattice volume of 192 x 96{sup 3} at β=3.55 corresponding to a lattice spacing of 0.064 fm. This ensemble is being generated as part of the CLS 2+1 flavor effort with improved Wilson fermions. Our simulations currently cover 5 lattice spacings ranging from 0.039 fm to 0.086 fm at various pion masses along chiral trajectories with either the sum of the quark masses kept fixed, or with the strange-quark mass at the physical value. The current status of simulations is briefly reviewed, including a short discussion of measured autocorrelation times and of the main features of the simulations. We then proceed to discuss the thermalization strategy employed for the generation of the physical quark-mass ensemble and present first results for some simple observables. Challenges encountered in the simulation are highlighted.

  18. The strange and light quark contributions to the nucleon mass from lattice QCD

    International Nuclear Information System (INIS)

    Bali, Gunnar S.; Collins, Sara; Goeckeler, Meinulf

    2011-12-01

    We determine the strangeness and light quark fractions of the nucleon mass by computing the quark line connected and disconnected contributions to the matrix elements m q left angle N vertical stroke anti qq vertical stroke N right angle in lattice QCD, using the non-perturbatively improved Sheikholeslami-Wohlert Wilson Fermionic action. We simulate n F =2 mass degenerate sea quarks with a pion mass of about 285 MeV and a lattice spacing ∼0.073 fm. The renormalization of the matrix elements involves mixing between contributions from different quark flavours. The pion-nucleon σ-term is extrapolated to physical quark masses exploiting the sea quark mass dependence of the nucleon mass. We obtain the renormalized values σ πN =(38±12) MeV at the physical point and f T s =σ s /m N =0.012(14) +10 -3 for the strangeness contribution at our larger than physical sea quark mass. (orig.)

  19. The strange and light quark contributions to the nucleon mass from lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Bali, Gunnar S.; Collins, Sara; Goeckeler, Meinulf [Regensburg Univ. (DE). Inst. fuer Theoretische Physik] (and others)

    2011-12-15

    We determine the strangeness and light quark fractions of the nucleon mass by computing the quark line connected and disconnected contributions to the matrix elements m{sub q} left angle N vertical stroke anti qq vertical stroke N right angle in lattice QCD, using the non-perturbatively improved Sheikholeslami-Wohlert Wilson Fermionic action. We simulate n{sub F}=2 mass degenerate sea quarks with a pion mass of about 285 MeV and a lattice spacing {approx}0.073 fm. The renormalization of the matrix elements involves mixing between contributions from different quark flavours. The pion-nucleon {sigma}-term is extrapolated to physical quark masses exploiting the sea quark mass dependence of the nucleon mass. We obtain the renormalized values {sigma}{sub {pi}}{sub N}=(38{+-}12) MeV at the physical point and f{sub T{sub s}}={sigma}{sub s}/m{sub N}=0.012(14){sup +10}{sub -3} for the strangeness contribution at our larger than physical sea quark mass. (orig.)

  20. Addition of electric arc furnace dust in hot metal changing the form of addition

    International Nuclear Information System (INIS)

    Marques Sobrinho, Vicente de Paulo Ferreira; Oliveira, Jose Roberto de; Vieira, Estefano Aparecido; Telles, Victor Bridi; Grillo, Felipe Fardin; Tenorio, Jorge Alberto Soares; Espinosa, Denise Crocce Romano

    2014-01-01

    This research aims to study the incorporation of the mass of electric arc furnace dust (EAFD), by addition in hot metal (1.78% Si) at a temperature of 1,400 degrees Celsius. The EAFD is from a steel plant producing long steel. The addition of the EAFD was as received, in the form of briquettes without agitation of the hot metal and in the form of briquettes with agitation of the hot metal. Previously, the EAFD was characterized using the following techniques: chemical analysis, size analysis, X-ray diffraction, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) microanalysis. The achievement of fusion experiments in laboratory scale, took place in a vertical tubular furnace with temperature control. The fusion experiments to assess the incorporation of EAFD mass used graphite crucibles. After cooling, the hot metal and the slag, remaining in the crucible, were weighed to do a mass balance. A flow of inert gas (argon) was maintained inside the furnace during the experiments. Results show that the experiment with addition of EAFD as received presents the best result of incorporating the mass of the final hot metal (1.73%) combined with the lowest percentage of volatilized mass of EAFD (46.52%). The experiment addition of EAFD in the form of briquette with agitation of hot metal presents the lowest percentage of slag mass (4.58%). The zinc content of volatilized EAFD (64.30%) is higher than the zinc content of the imported ore concentrate (52%) and zinc content of the national ore concentrate (12% to 39%). The presence of lead and cadmium in the slag characterizing it as a hazardous solid waste. (author)

  1. Menopausal Hot Flashes and White Matter Hyperintensities

    Science.gov (United States)

    Thurston, Rebecca C.; Aizenstein, Howard J.; Derby, Carol A.; Sejdić, Ervin; Maki, Pauline M.

    2015-01-01

    Objective Hot flashes are the classic menopausal symptom. Emerging data links hot flashes to cardiovascular disease (CVD) risk, yet how hot flashes are related to brain health is poorly understood. We examined the relationship between hot flashes - measured via physiologic monitor and self-report - and white matter hyperintensities (WMH) among midlife women. Methods Twenty midlife women ages 40-60 without clinical CVD, with their uterus and both ovaries, and not taking hormone therapy were recruited. Women underwent 24 hours of ambulatory physiologic and diary hot flash monitoring to quantify hot flashes; magnetic resonance imaging to assess WMH burden; 72 hours of actigraphy and questionnaires to quantify sleep; and a blood draw, questionnaires, and physical measures to quantify demographics and CVD risk factors. Test of a priori hypotheses regarding relations between physiologically-monitored and self-reported wake and sleep hot flashes and WMH were conducted in linear regression models. Results More physiologically-monitored hot flashes during sleep were associated with greater WMH, controlling for age, race, and body mass index [beta(standard error)=.0002 (.0001), p=.03]. Findings persisted controlling for sleep characteristics and additional CVD risk factors. No relations were observed for self-reported hot flashes. Conclusions More physiologically-monitored hot flashes during sleep were associated with greater WMH burden among midlife women free of clinical CVD. Results suggest that relations between hot flashes and CVD risk observed in the periphery may extend to the brain. Future work should consider the unique role of sleep hot flashes in brain health. PMID:26057822

  2. ON THE EMERGENT SPECTRA OF HOT PROTOPLANET COLLISION AFTERGLOWS

    International Nuclear Information System (INIS)

    Miller-Ricci, Eliza; Meyer, Michael R.; Seager, Sara; Elkins-Tanton, Linda

    2009-01-01

    We explore the appearance of terrestrial planets in formation by studying the emergent spectra of hot molten protoplanets during their collisional formation. While such collisions are rare, the surfaces of these bodies may remain hot at temperatures of 1000-3000 K for up to millions of years during the epoch of their formation (of duration 10-100 Myr). These objects are luminous enough in the thermal infrared to be observable with current and next-generation optical/IR telescopes, provided that the atmosphere of the forming planet permits astronomers to observe brightness temperatures approaching that of the molten surface. Detectability of a collisional afterglow depends on properties of the planet's atmosphere-primarily on the mass of the atmosphere. A planet with a thin atmosphere is more readily detected, because there is little atmosphere to obscure the hot surface. Paradoxically, a more massive atmosphere prevents one from easily seeing the hot surface, but also keeps the planet hot for a longer time. In terms of planetary mass, more massive planets are also easier to detect than smaller ones because of their larger emitting surface areas-up to a factor of 10 in brightness between 1 and 10 M + planets. We present preliminary calculations assuming a range of protoplanet masses (1-10 M + ), surface pressures (1-1000 bar), and atmospheric compositions, for molten planets with surface temperatures ranging from 1000 to 1800 K, in order to explore the diversity of emergent spectra that are detectable. While current 8 to 10 m class ground-based telescopes may detect hot protoplanets at wide orbital separations beyond 30 AU (if they exist), we will likely have to wait for next-generation extremely large telescopes or improved diffraction suppression techniques to find terrestrial planets in formation within several AU of their host stars.

  3. Masses of the light hadrons in the chiral and cloudy bag models

    International Nuclear Information System (INIS)

    Saito, Koichi.

    1983-10-01

    The masses of the light hadrons except for the pion are calculated in the stable chiral and cloudy bag models with the massless or massive u, d quark and pion. Two difficulties in these models, i.e. the lack of stability and the divergence of the quark self-energy, are removed by taking account of a simple non-local quark-pion interaction. The effects of the finite size of the qq-bar pion and the behavior of the quark self-energy are discussed in detail. In our calculation the bag self-energy due to the pion has an important role in the origin of the N-Δ and the Σ-Λ mass differences. The baryon octet and decuplet masses are well reproduced by the present model. (author)

  4. Future cosmological sensitivity for hot dark matter axions

    CERN Document Server

    Archidiacono, Maria; Hamann, Jan; Hannestad, Steen; Raffelt, Georg; Wong, Yvonne Y Y

    2015-01-01

    We study the potential of a future, large-volume photometric survey to constrain the axion mass $m_a$ in the hot dark matter limit. Future surveys such as Euclid will have significantly more constraining power than current observations for hot dark matter. Nonetheless, the lowest accessible axion masses are limited by the fact that axions lighter than $\\sim 0.15$ eV decouple before the QCD epoch, assumed here to occur at a temperature $T_{\\rm QCD} \\sim 170$ MeV; this leaves an axion population of such low density that its late-time cosmological impact is negligible. For larger axion masses, $m_a \\gtrsim 0.15$ eV, where axions remain in equilibrium until after the QCD phase transition, we find that a Euclid-like survey combined with Planck CMB data can detect $m_a$ at very high significance. Our conclusions are robust against assumptions about prior knowledge of the neutrino mass. Given that the proposed IAXO solar axion search is sensitive to $m_a\\lesssim 0.2$ eV, the axion mass range probed by cosmology is n...

  5. Slow hot carrier cooling in cesium lead iodide perovskites

    Science.gov (United States)

    Shen, Qing; Ripolles, Teresa S.; Even, Jacky; Ogomi, Yuhei; Nishinaka, Koji; Izuishi, Takuya; Nakazawa, Naoki; Zhang, Yaohong; Ding, Chao; Liu, Feng; Toyoda, Taro; Yoshino, Kenji; Minemoto, Takashi; Katayama, Kenji; Hayase, Shuzi

    2017-10-01

    Lead halide perovskites are attracting a great deal of interest for optoelectronic applications such as solar cells, LEDs, and lasers because of their unique properties. In solar cells, heat dissipation by hot carriers results in a major energy loss channel responsible for the Shockley-Queisser efficiency limit. Hot carrier solar cells offer the possibility to overcome this limit and achieve energy conversion efficiency as high as 66% by extracting hot carriers. Therefore, fundamental studies on hot carrier relaxation dynamics in lead halide perovskites are important. Here, we elucidated the hot carrier cooling dynamics in all-inorganic cesium lead iodide (CsPbI3) perovskite using transient absorption spectroscopy. We observe that the hot carrier cooling rate in CsPbI3 decreases as the fluence of the pump light increases and the cooling is as slow as a few 10 ps when the photoexcited carrier density is 7 × 1018 cm-3, which is attributed to phonon bottleneck for high photoexcited carrier densities. Our findings suggest that CsPbI3 has a potential for hot carrier solar cell applications.

  6. Masses of open-flavour heavy-light hybrids from QCD sum-rules

    Energy Technology Data Exchange (ETDEWEB)

    Ho, J. [Department of Physics and Engineering Physics, University of Saskatchewan,Saskatoon, SK, S7N 5E2 (Canada); Harnett, D. [Department of Physics, University of the Fraser Valley,Abbotsford, BC, V2S 7M8 (Canada); Steele, T.G. [Department of Physics and Engineering Physics, University of Saskatchewan,Saskatoon, SK, S7N 5E2 (Canada)

    2017-05-29

    We use QCD Laplace sum-rules to predict masses of open-flavour heavy-light hybrids where one of the hybrid’s constituent quarks is a charm or bottom and the other is an up, down, or strange. We compute leading-order, diagonal correlation functions of several hybrid interpolating currents, taking into account QCD condensates up to dimension-six, and extract hybrid mass predictions for all J{sup P}∈{0"±, 1"±}, as well as explore possible mixing effects with conventional quark-antiquark mesons. Within theoretical uncertainties, our results are consistent with a degeneracy between the heavy-nonstrange and heavy-strange hybrids in all J{sup P} channels. We find a similar mass hierarchy of 1{sup +}, 1{sup −}, and 0{sup +} states (a 1{sup +} state lighter than essentially degenerate 1{sup −} and 0{sup +} states) in both the charm and bottom sectors, and discuss an interpretation for the 0{sup −} states. If conventional meson mixing is present the effect is an increase in the hybrid mass prediction, and we estimate an upper bound on this effect.

  7. Constraining the Physical State of the Hot Gas Halos in NGC 4649 and NGC 5846

    Science.gov (United States)

    Paggi, Alessandro; Kim, Dong-Woo; Anderson, Craig; Burke, Doug; D'Abrusco, Raffaele; Fabbiano, Giuseppina; Fruscione, Antonella; Gokas, Tara; Lauer, Jen; McCollough, Michael; Morgan, Doug; Mossman, Amy; O'Sullivan, Ewan; Trinchieri, Ginevra; Vrtilek, Saeqa; Pellegrini, Silvia; Romanowsky, Aaron J.; Brodie, Jean

    2017-07-01

    We present results of a joint Chandra/XMM-Newton analysis of the early-type galaxies NGC 4649 and NGC 5846 aimed at investigating differences between mass profiles derived from X-ray data and those from optical data, to probe the state of the hot interstellar medium (ISM) in these galaxies. If the hot ISM is at a given radius in hydrostatic equilibrium (HE), the X-ray data can be used to measure the total enclosed mass of the galaxy. Differences from optically derived mass distributions therefore yield information about departures from HE in the hot halos. The X-ray mass profiles in different angular sectors of NGC 4649 are generally smooth with no significant azimuthal asymmetries within 12 kpc. Extrapolation of these profiles beyond this scale yields results consistent with the optical estimate. However, in the central region (rdisappears in the NW direction, where the emission is smooth and extended. In this sector we find consistent X-ray and optical mass profiles, suggesting that the hot halo is not responding to strong nongravitational forces.

  8. Effects of Dissociation/Recombination on the Day–Night Temperature Contrasts of Ultra-hot Jupiters

    Science.gov (United States)

    Komacek, Thaddeus D.; Tan, Xianyu

    2018-05-01

    Secondary eclipse observations of ultra-hot Jupiters have found evidence that hydrogen is dissociated on their daysides. Additionally, full-phase light curve observations of ultra-hot Jupiters show a smaller day-night emitted flux contrast than that expected from previous theory. Recently, it was proposed by Bell & Cowan (2018) that the heat intake to dissociate hydrogen and heat release due to recombination of dissociated hydrogen can affect the atmospheric circulation of ultra-hot Jupiters. In this work, we add cooling/heating due to dissociation/recombination into the analytic theory of Komacek & Showman (2016) and Zhang & Showman (2017) for the dayside-nightside temperature contrasts of hot Jupiters. We find that at high values of incident stellar flux, the day-night temperature contrast of ultra-hot Jupiters may decrease with increasing incident stellar flux due to dissociation/recombination, the opposite of that expected without including the effects of dissociation/recombination. We propose that a combination of a greater number of full-phase light curve observations of ultra-hot Jupiters and future General Circulation Models that include the effects of dissociation/recombination could determine in detail how the atmospheric circulation of ultra-hot Jupiters differs from that of cooler planets.

  9. Galaxy and mass assembly (GAMA): the consistency of GAMA and WISE derived mass-to-light ratios

    Science.gov (United States)

    Kettlety, T.; Hesling, J.; Phillipps, S.; Bremer, M. N.; Cluver, M. E.; Taylor, E. N.; Bland-Hawthorn, J.; Brough, S.; De Propris, R.; Driver, S. P.; Holwerda, B. W.; Kelvin, L. S.; Sutherland, W.; Wright, A. H.

    2018-01-01

    Recent work has suggested that mid-IR wavelengths are optimal for estimating the mass-to-light ratios of stellar populations and hence the stellar masses of galaxies. We compare stellar masses deduced from spectral energy distribution (SED) models, fitted to multiwavelength optical-NIR photometry, to luminosities derived from WISE photometry in the W1 and W2 bands at 3.6 and 4.5 μm for non-star forming galaxies. The SED-derived masses for a carefully selected sample of low-redshift (z ≤ 0.15) passive galaxies agree with the prediction from stellar population synthesis models such that M*/LW1 ≃ 0.6 for all such galaxies, independent of other stellar population parameters. The small scatter between masses predicted from the optical SED and from the WISE measurements implies that random errors (as opposed to systematic ones such as the use of different initial mass functions) are smaller than previous, deliberately conservative, estimates for the SED fits. This test is subtly different from simultaneously fitting at a wide range of optical and mid-IR wavelengths, which may just generate a compromised fit: we are directly checking that the best-fitting model to the optical data generates an SED whose M*/LW1 is also consistent with separate mid-IR data. We confirm that for passive low-redshift galaxies a fixed M*/LW1 = 0.65 can generate masses at least as accurate as those obtained from more complex methods. Going beyond the mean value, in agreement with expectations from the models, we see a modest change in M*/LW1 with SED fitted stellar population age but an insignificant one with metallicity.

  10. Numerical Investigation of the Main Characteristics of Heat and Mass Transfer while Heating the Heterogeneous Water Droplet in the Hot Gases

    Directory of Open Access Journals (Sweden)

    Piskunov Maxim V.

    2016-01-01

    Full Text Available The processes of heat and evaporation of heterogeneous water droplet with solid (by the example of carbon inclusion in hot (from 800 K to 1500 K gases were investigated by the developed models of heat and mass transfer. We defined the limited conditions, characteristics of the droplet and the gas medium which are sufficient for implementing the “explosive” destruction of heterogeneous droplet due to intensive vaporization on an inner interface, and intensive evaporation of liquid from an external (free droplet surface. The values of the main characteristic of the process (period from start of heating to “explosive” destruction obtained in response to using various heat and mass transfer models were compared.

  11. New Light on Dark Energy

    Science.gov (United States)

    2008-01-01

    Using ESO's Very Large Telescope Interferometer, astronomers have probed the inner parts of the disc of material surrounding a young stellar object, witnessing how it gains its mass before becoming an adult. ESO PR Photo 03/08 ESO PR Photo 03a/08 The disc around MWC 147 (Artist's Impression) The astronomers had a close look at the object known as MWC 147, lying about 2,600 light years away towards the constellation of Monoceros ('the Unicorn'). MWC 147 belongs to the family of Herbig Ae/Be objects. These have a few times the mass of our Sun and are still forming, increasing in mass by swallowing material present in a surrounding disc. MWC 147 is less than half a million years old. If one associated the middle-aged, 4.6 billion year old Sun with a person in his early forties, MWC 147 would be a 1-day-old baby [1]. The morphology of the inner environment of these young stars is however a matter of debate and knowledge of it is important to better understand how stars and their cortège of planets form. The astronomers Stefan Kraus, Thomas Preibisch, and Keiichi Ohnaka have used the four 8.2-m Unit Telescopes of ESO's Very Large Telescope to this purpose, combining the light from two or three telescopes with the MIDI and AMBER instruments. "With our VLTI/MIDI and VLTI/AMBER observations of MWC147, we combine, for the first time, near- and mid-infrared interferometric observations of a Herbig Ae/Be star, providing a measurement of the disc size over a wide wavelength range [2]," said Stefan Kraus, lead-author of the paper reporting the results. "Different wavelength regimes trace different temperatures, allowing us to probe the disc's geometry on the smaller scale, but also to constrain how the temperature changes with the distance from the star." The near-infrared observations probe hot material with temperatures of up to a few thousand degrees in the innermost disc regions, while the mid-infrared observations trace cooler dust further out in the disc. The

  12. Precision measurement of the mass difference between light nuclei and anti-nuclei

    CERN Document Server

    Adam, Jaroslav; Aggarwal, Madan Mohan; Aglieri Rinella, Gianluca; Agnello, Michelangelo; Agrawal, Neelima; Ahammed, Zubayer; Ahmed, Ijaz; Ahn, Sang Un; Aimo, Ilaria; Aiola, Salvatore; Ajaz, Muhammad; Akindinov, Alexander; Alam, Sk Noor; Aleksandrov, Dmitry; Alessandro, Bruno; Alexandre, Didier; Alfaro Molina, Jose Ruben; Alici, Andrea; Alkin, Anton; Alme, Johan; Alt, Torsten; Altinpinar, Sedat; Altsybeev, Igor; Alves Garcia Prado, Caio; Andrei, Cristian; Andronic, Anton; Anguelov, Venelin; Anielski, Jonas; Anticic, Tome; Antinori, Federico; Antonioli, Pietro; Aphecetche, Laurent Bernard; Appelshaeuser, Harald; Arcelli, Silvia; Armesto Perez, Nestor; Arnaldi, Roberta; Aronsson, Tomas; Arsene, Ionut Cristian; Arslandok, Mesut; Augustinus, Andre; Averbeck, Ralf Peter; Azmi, Mohd Danish; Bach, Matthias Jakob; Badala, Angela; Baek, Yong Wook; Bagnasco, Stefano; Bailhache, Raphaelle Marie; Bala, Renu; Baldisseri, Alberto; Ball, Markus; Baltasar Dos Santos Pedrosa, Fernando; Baral, Rama Chandra; Barbano, Anastasia Maria; Barbera, Roberto; Barile, Francesco; Barnafoldi, Gergely Gabor; Barnby, Lee Stuart; Ramillien Barret, Valerie; Bartalini, Paolo; Bartke, Jerzy Gustaw; Bartsch, Esther; Basile, Maurizio; Bastid, Nicole; Basu, Sumit; Bathen, Bastian; Batigne, Guillaume; Batista Camejo, Arianna; Batyunya, Boris; Batzing, Paul Christoph; Bearden, Ian Gardner; Beck, Hans; Bedda, Cristina; Behera, Nirbhay Kumar; Belikov, Iouri; Bellini, Francesca; Bello Martinez, Hector; Bellwied, Rene; Belmont Iii, Ronald John; Belmont Moreno, Ernesto; Belyaev, Vladimir; Bencedi, Gyula; Beole, Stefania; Berceanu, Ionela; Bercuci, Alexandru; Berdnikov, Yaroslav; Berenyi, Daniel; Bertens, Redmer Alexander; Berzano, Dario; Betev, Latchezar; Bhasin, Anju; Bhat, Inayat Rasool; Bhati, Ashok Kumar; Bhattacharjee, Buddhadeb; Bhom, Jihyun; Bianchi, Livio; Bianchi, Nicola; Bianchin, Chiara; Bielcik, Jaroslav; Bielcikova, Jana; Bilandzic, Ante; Biswas, Saikat; Bjelogrlic, Sandro; Blanco, Fernando; Blau, Dmitry; Blume, Christoph; Bock, Friederike; Bogdanov, Alexey; Boggild, Hans; Boldizsar, Laszlo; Bombara, Marek; Book, Julian Heinz; Borel, Herve; Borissov, Alexander; Borri, Marcello; Bossu, Francesco; Botje, Michiel; Botta, Elena; Boettger, Stefan; Braun-Munzinger, Peter; Bregant, Marco; Breitner, Timo Gunther; Broker, Theo Alexander; Browning, Tyler Allen; Broz, Michal; Brucken, Erik Jens; Bruna, Elena; Bruno, Giuseppe Eugenio; Budnikov, Dmitry; Buesching, Henner; Bufalino, Stefania; Buncic, Predrag; Busch, Oliver; Buthelezi, Edith Zinhle; Buxton, Jesse Thomas; Caffarri, Davide; Cai, Xu; Caines, Helen Louise; Calero Diaz, Liliet; Caliva, Alberto; Calvo Villar, Ernesto; Camerini, Paolo; Carena, Francesco; Carena, Wisla; Castillo Castellanos, Javier Ernesto; Castro, Andrew John; Casula, Ester Anna Rita; Cavicchioli, Costanza; Ceballos Sanchez, Cesar; Cepila, Jan; Cerello, Piergiorgio; Chang, Beomsu; Chapeland, Sylvain; Chartier, Marielle; Charvet, Jean-Luc Fernand; Chattopadhyay, Subhasis; Chattopadhyay, Sukalyan; Chelnokov, Volodymyr; Cherney, Michael Gerard; Cheshkov, Cvetan Valeriev; Cheynis, Brigitte; Chibante Barroso, Vasco Miguel; Dobrigkeit Chinellato, David; Chochula, Peter; Choi, Kyungeon; Chojnacki, Marek; Choudhury, Subikash; Christakoglou, Panagiotis; Christensen, Christian Holm; Christiansen, Peter; Chujo, Tatsuya; Chung, Suh-Urk; Cicalo, Corrado; Cifarelli, Luisa; Cindolo, Federico; Cleymans, Jean Willy Andre; Colamaria, Fabio Filippo; Colella, Domenico; Collu, Alberto; Colocci, Manuel; Conesa Balbastre, Gustavo; Conesa Del Valle, Zaida; Connors, Megan Elizabeth; Contreras Nuno, Jesus Guillermo; Cormier, Thomas Michael; Corrales Morales, Yasser; Cortes Maldonado, Ismael; Cortese, Pietro; Cosentino, Mauro Rogerio; Costa, Filippo; Crochet, Philippe; Cruz Albino, Rigoberto; Cuautle Flores, Eleazar; Cunqueiro Mendez, Leticia; Dahms, Torsten; Dainese, Andrea; Danu, Andrea; Das, Debasish; Das, Indranil; Das, Supriya; Dash, Ajay Kumar; Dash, Sadhana; De, Sudipan; De Caro, Annalisa; De Cataldo, Giacinto; De Cuveland, Jan; De Falco, Alessandro; De Gruttola, Daniele; De Marco, Nora; De Pasquale, Salvatore; Deisting, Alexander; Deloff, Andrzej; Denes, Ervin Sandor; D'Erasmo, Ginevra; Di Bari, Domenico; Di Mauro, Antonio; Di Nezza, Pasquale; Diaz Corchero, Miguel Angel; Dietel, Thomas; Dillenseger, Pascal; Divia, Roberto; Djuvsland, Oeystein; Dobrin, Alexandru Florin; Dobrowolski, Tadeusz Antoni; Domenicis Gimenez, Diogenes; Donigus, Benjamin; Dordic, Olja; Dubey, Anand Kumar; Dubla, Andrea; Ducroux, Laurent; Dupieux, Pascal; Ehlers Iii, Raymond James; Elia, Domenico; Engel, Heiko; Erazmus, Barbara Ewa; Erhardt, Filip; Eschweiler, Dominic; Espagnon, Bruno; Estienne, Magali Danielle; Esumi, Shinichi; Evans, David; Evdokimov, Sergey; Eyyubova, Gyulnara; Fabbietti, Laura; Fabris, Daniela; Faivre, Julien; Fantoni, Alessandra; Fasel, Markus; Feldkamp, Linus; Felea, Daniel; Feliciello, Alessandro; Feofilov, Grigorii; Ferencei, Jozef; Fernandez Tellez, Arturo; Gonzalez Ferreiro, Elena; Ferretti, Alessandro; Festanti, Andrea; Figiel, Jan; Araujo Silva Figueredo, Marcel; Filchagin, Sergey; Finogeev, Dmitry; Fionda, Fiorella; Fiore, Enrichetta Maria; Fleck, Martin Gabriel; Floris, Michele; Foertsch, Siegfried Valentin; Foka, Panagiota; Fokin, Sergey; Fragiacomo, Enrico; Francescon, Andrea; Frankenfeld, Ulrich Michael; Fuchs, Ulrich; Furget, Christophe; Furs, Artur; Fusco Girard, Mario; Gaardhoeje, Jens Joergen; Gagliardi, Martino; Gago Medina, Alberto Martin; Gallio, Mauro; Gangadharan, Dhevan Raja; Ganoti, Paraskevi; Gao, Chaosong; Garabatos Cuadrado, Jose; Garcia-Solis, Edmundo Javier; Gargiulo, Corrado; Gasik, Piotr Jan; Germain, Marie; Gheata, Andrei George; Gheata, Mihaela; Ghosh, Premomoy; Ghosh, Sanjay Kumar; Gianotti, Paola; Giubellino, Paolo; Giubilato, Piero; Gladysz-Dziadus, Ewa; Glassel, Peter; Gomez Ramirez, Andres; Gonzalez Zamora, Pedro; Gorbunov, Sergey; Gorlich, Lidia Maria; Gotovac, Sven; Grabski, Varlen; Graczykowski, Lukasz Kamil; Grelli, Alessandro; Grigoras, Alina Gabriela; Grigoras, Costin; Grigoryev, Vladislav; Grigoryan, Ara; Grigoryan, Smbat; Grynyov, Borys; Grion, Nevio; Grosse-Oetringhaus, Jan Fiete; Grossiord, Jean-Yves; Grosso, Raffaele; Guber, Fedor; Guernane, Rachid; Guerzoni, Barbara; Gulbrandsen, Kristjan Herlache; Gulkanyan, Hrant; Gunji, Taku; Gupta, Anik; Gupta, Ramni; Haake, Rudiger; Haaland, Oystein Senneset; Hadjidakis, Cynthia Marie; Haiduc, Maria; Hamagaki, Hideki; Hamar, Gergoe; Hanratty, Luke David; Hansen, Alexander; Harris, John William; Hartmann, Helvi; Harton, Austin Vincent; Hatzifotiadou, Despina; Hayashi, Shinichi; Heckel, Stefan Thomas; Heide, Markus Ansgar; Helstrup, Haavard; Herghelegiu, Andrei Ionut; Herrera Corral, Gerardo Antonio; Hess, Benjamin Andreas; Hetland, Kristin Fanebust; Hilden, Timo Eero; Hillemanns, Hartmut; Hippolyte, Boris; Hristov, Peter Zahariev; Huang, Meidana; Humanic, Thomas; Hussain, Nur; Hussain, Tahir; Hutter, Dirk; Hwang, Dae Sung; Ilkaev, Radiy; Ilkiv, Iryna; Inaba, Motoi; Ionita, Costin; Ippolitov, Mikhail; Irfan, Muhammad; Ivanov, Marian; Ivanov, Vladimir; Izucheev, Vladimir; Jacobs, Peter Martin; Jahnke, Cristiane; Jang, Haeng Jin; Janik, Malgorzata Anna; Pahula Hewage, Sandun; Jena, Chitrasen; Jena, Satyajit; Jimenez Bustamante, Raul Tonatiuh; Jones, Peter Graham; Jung, Hyungtaik; Jusko, Anton; Kalinak, Peter; Kalweit, Alexander Philipp; Kamin, Jason Adrian; Kang, Ju Hwan; Kaplin, Vladimir; Kar, Somnath; Karasu Uysal, Ayben; Karavichev, Oleg; Karavicheva, Tatiana; Karpechev, Evgeny; Kebschull, Udo Wolfgang; Keidel, Ralf; Keijdener, Darius Laurens; Keil, Markus; Khan, Kamal; Khan, Mohammed Mohisin; Khan, Palash; Khan, Shuaib Ahmad; Khanzadeev, Alexei; Kharlov, Yury; Kileng, Bjarte; Kim, Beomkyu; Kim, Do Won; Kim, Dong Jo; Kim, Hyeonjoong; Kim, Jinsook; Kim, Mimae; Kim, Minwoo; Kim, Se Yong; Kim, Taesoo; Kirsch, Stefan; Kisel, Ivan; Kiselev, Sergey; Kisiel, Adam Ryszard; Kiss, Gabor; Klay, Jennifer Lynn; Klein, Carsten; Klein, Jochen; Klein-Boesing, Christian; Kluge, Alexander; Knichel, Michael Linus; Knospe, Anders Garritt; Kobayashi, Taiyo; Kobdaj, Chinorat; Kofarago, Monika; Kohler, Markus Konrad; Kollegger, Thorsten; Kolozhvari, Anatoly; Kondratev, Valerii; Kondratyeva, Natalia; Kondratyuk, Evgeny; Konevskikh, Artem; Kouzinopoulos, Charalampos; Kovalenko, Vladimir; Kowalski, Marek; Kox, Serge; Koyithatta Meethaleveedu, Greeshma; Kral, Jiri; Kralik, Ivan; Kravcakova, Adela; Krelina, Michal; Kretz, Matthias; Krivda, Marian; Krizek, Filip; Kryshen, Evgeny; Krzewicki, Mikolaj; Kubera, Andrew Michael; Kucera, Vit; Kucheryaev, Yury; Kugathasan, Thanushan; Kuhn, Christian Claude; Kuijer, Paulus Gerardus; Kulakov, Igor; Kumar, Jitendra; Lokesh, Kumar; Kurashvili, Podist; Kurepin, Alexander; Kurepin, Alexey; Kuryakin, Alexey; Kushpil, Svetlana; Kweon, Min Jung; Kwon, Youngil; La Pointe, Sarah Louise; La Rocca, Paola; Lagana Fernandes, Caio; Lakomov, Igor; Langoy, Rune; Lara Martinez, Camilo Ernesto; Lardeux, Antoine Xavier; Lattuca, Alessandra; Laudi, Elisa; Lea, Ramona; Leardini, Lucia; Lee, Graham Richard; Lee, Seongjoo; Legrand, Iosif; Lehnert, Joerg Walter; Lemmon, Roy Crawford; Lenti, Vito; Leogrande, Emilia; Leon Monzon, Ildefonso; Leoncino, Marco; Levai, Peter; Li, Shuang; Li, Xiaomei; Lien, Jorgen Andre; Lietava, Roman; Lindal, Svein; Lindenstruth, Volker; Lippmann, Christian; Lisa, Michael Annan; Ljunggren, Hans Martin; Lodato, Davide Francesco; Lonne, Per-Ivar; Loggins, Vera Renee; Loginov, Vitaly; Loizides, Constantinos; Lopez, Xavier Bernard; Lopez Torres, Ernesto; Lowe, Andrew John; Lu, Xianguo; Luettig, Philipp Johannes; Lunardon, Marcello; Luparello, Grazia; Maevskaya, Alla; Mager, Magnus; Mahajan, Sanjay; Mahmood, Sohail Musa; Maire, Antonin; Majka, Richard Daniel; Malaev, Mikhail; Maldonado Cervantes, Ivonne Alicia; Malinina, Liudmila; Mal'Kevich, Dmitry; Malzacher, Peter; Mamonov, Alexander; Manceau, Loic Henri Antoine; Manko, Vladislav; Manso, Franck; Manzari, Vito; Marchisone, Massimiliano; Mares, Jiri; Margagliotti, Giacomo Vito; Margotti, Anselmo; Margutti, Jacopo; Marin, Ana Maria; Markert, Christina; Marquard, Marco; Martashvili, Irakli; Martin, Nicole Alice; Martin Blanco, Javier; Martinengo, Paolo; Martinez Hernandez, Mario Ivan; Martinez-Garcia, Gines; Martinez Pedreira, Miguel; Martynov, Yevgen; Mas, Alexis Jean-Michel; Masciocchi, Silvia; Masera, Massimo; Masoni, Alberto; Massacrier, Laure Marie; Mastroserio, Annalisa; Matyja, Adam Tomasz; Mayer, Christoph; Mazer, Joel Anthony; Mazzoni, Alessandra Maria; Mcdonald, Daniel; Meddi, Franco; Menchaca-Rocha, Arturo Alejandro; Meninno, Elisa; Mercado-Perez, Jorge; Meres, Michal; Miake, Yasuo; Mieskolainen, Matti Mikael; Mikhaylov, Konstantin; Milano, Leonardo; Milosevic, Jovan; Minervini, Lazzaro Manlio; Mischke, Andre; Mishra, Aditya Nath; Miskowiec, Dariusz Czeslaw; Mitra, Jubin; Mitu, Ciprian Mihai; Mohammadi, Naghmeh; Mohanty, Bedangadas; Molnar, Levente; Montano Zetina, Luis Manuel; Montes Prado, Esther; Morando, Maurizio; Moreira De Godoy, Denise Aparecida; Moretto, Sandra; Morreale, Astrid; Morsch, Andreas; Muccifora, Valeria; Mudnic, Eugen; Muhlheim, Daniel Michael; Muhuri, Sanjib; Mukherjee, Maitreyee; Muller, Hans; Mulligan, James Declan; Gameiro Munhoz, Marcelo; Murray, Sean; Musa, Luciano; Musinsky, Jan; Nandi, Basanta Kumar; Nania, Rosario; Nappi, Eugenio; Naru, Muhammad Umair; Nattrass, Christine; Nayak, Kishora; Nayak, Tapan Kumar; Nazarenko, Sergey; Nedosekin, Alexander; Nellen, Lukas; Ng, Fabian; Nicassio, Maria; Niculescu, Mihai; Niedziela, Jeremi; Nielsen, Borge Svane; Nikolaev, Sergey; Nikulin, Sergey; Nikulin, Vladimir; Noferini, Francesco; Nomokonov, Petr; Nooren, Gerardus; Norman, Jaime; Nyanin, Alexander; Nystrand, Joakim Ingemar; Oeschler, Helmut Oskar; Oh, Saehanseul; Oh, Sun Kun; Ohlson, Alice Elisabeth; Okatan, Ali; Okubo, Tsubasa; Olah, Laszlo; Oleniacz, Janusz; Oliveira Da Silva, Antonio Carlos; Oliver, Michael Henry; Onderwaater, Jacobus; Oppedisano, Chiara; Ortiz Velasquez, Antonio; Oskarsson, Anders Nils Erik; Otwinowski, Jacek Tomasz; Oyama, Ken; Ozdemir, Mahmut; Pachmayer, Yvonne Chiara; Pagano, Paola; Paic, Guy; Pajares Vales, Carlos; Pal, Susanta Kumar; Pan, Jinjin; Pandey, Ashutosh Kumar; Pant, Divyash; Papikyan, Vardanush; Pappalardo, Giuseppe; Pareek, Pooja; Park, Woojin; Parmar, Sonia; Passfeld, Annika; Paticchio, Vincenzo; Paul, Biswarup; Pawlak, Tomasz Jan; Peitzmann, Thomas; Pereira Da Costa, Hugo Denis Antonio; Pereira De Oliveira Filho, Elienos; Peresunko, Dmitry Yurevich; Perez Lara, Carlos Eugenio; Peskov, Vladimir; Pestov, Yury; Petracek, Vojtech; Petrov, Viacheslav; Petrovici, Mihai; Petta, Catia; Piano, Stefano; Pikna, Miroslav; Pillot, Philippe; Pinazza, Ombretta; Pinsky, Lawrence; Piyarathna, Danthasinghe; Ploskon, Mateusz Andrzej; Planinic, Mirko; Pluta, Jan Marian; Pochybova, Sona; Podesta Lerma, Pedro Luis Manuel; Poghosyan, Martin; Polishchuk, Boris; Poljak, Nikola; Poonsawat, Wanchaloem; Pop, Amalia; Porteboeuf, Sarah Julie; Porter, R Jefferson; Pospisil, Jan; Prasad, Sidharth Kumar; Preghenella, Roberto; Prino, Francesco; Pruneau, Claude Andre; Pshenichnov, Igor; Puccio, Maximiliano; Puddu, Giovanna; Pujahari, Prabhat Ranjan; Punin, Valery; Putschke, Jorn Henning; Qvigstad, Henrik; Rachevski, Alexandre; Raha, Sibaji; Rajput, Sonia; Rak, Jan; Rakotozafindrabe, Andry Malala; Ramello, Luciano; Raniwala, Rashmi; Raniwala, Sudhir; Rasanen, Sami Sakari; Rascanu, Bogdan Theodor; Rathee, Deepika; Razazi, Vahedeh; Read, Kenneth Francis; Real, Jean-Sebastien; Redlich, Krzysztof; Reed, Rosi Jan; Rehman, Attiq Ur; Reichelt, Patrick Simon; Reicher, Martijn; Reidt, Felix; Ren, Xiaowen; Renfordt, Rainer Arno Ernst; Reolon, Anna Rita; Reshetin, Andrey; Rettig, Felix Vincenz; Revol, Jean-Pierre; Reygers, Klaus Johannes; Riabov, Viktor; Ricci, Renato Angelo; Richert, Tuva Ora Herenui; Richter, Matthias Rudolph; Riedler, Petra; Riegler, Werner; Riggi, Francesco; Ristea, Catalin-Lucian; Rivetti, Angelo; Rocco, Elena; Rodriguez Cahuantzi, Mario; Rodriguez Manso, Alis; Roeed, Ketil; Rogochaya, Elena; Rohr, David Michael; Roehrich, Dieter; Romita, Rosa; Ronchetti, Federico; Ronflette, Lucile; Rosnet, Philippe; Rossi, Andrea; Roukoutakis, Filimon; Roy, Ankhi; Roy, Christelle Sophie; Roy, Pradip Kumar; Rubio Montero, Antonio Juan; Rui, Rinaldo; Russo, Riccardo; Ryabinkin, Evgeny; Ryabov, Yury; Rybicki, Andrzej; Sadovskiy, Sergey; Safarik, Karel; Sahlmuller, Baldo; Sahoo, Pragati; Sahoo, Raghunath; Sahoo, Sarita; Sahu, Pradip Kumar; Saini, Jogender; Sakai, Shingo; Saleh, Mohammad Ahmad; Salgado Lopez, Carlos Alberto; Salzwedel, Jai Samuel Nielsen; Sambyal, Sanjeev Singh; Samsonov, Vladimir; Sanchez Castro, Xitzel; Sandor, Ladislav; Sandoval, Andres; Sano, Masato; Santagati, Gianluca; Sarkar, Debojit; Scapparone, Eugenio; Scarlassara, Fernando; Scharenberg, Rolf Paul; Schiaua, Claudiu Cornel; Schicker, Rainer Martin; Schmidt, Christian Joachim; Schmidt, Hans Rudolf; Schuchmann, Simone; Schukraft, Jurgen; Schulc, Martin; Schuster, Tim Robin; Schutz, Yves Roland; Schwarz, Kilian Eberhard; Schweda, Kai Oliver; Scioli, Gilda; Scomparin, Enrico; Scott, Rebecca Michelle; Seeder, Karin Soraya; Seger, Janet Elizabeth; Sekiguchi, Yuko; Selyuzhenkov, Ilya; Senosi, Kgotlaesele; Seo, Jeewon; Serradilla Rodriguez, Eulogio; Sevcenco, Adrian; Shabanov, Arseniy; Shabetai, Alexandre; Shadura, Oksana; Shahoyan, Ruben; Shangaraev, Artem; Sharma, Ankita; Sharma, Natasha; Shigaki, Kenta; Shtejer Diaz, Katherin; Sibiryak, Yury; Siddhanta, Sabyasachi; Sielewicz, Krzysztof Marek; Siemiarczuk, Teodor; Silvermyr, David Olle Rickard; Silvestre, Catherine Micaela; Simatovic, Goran; Simonetti, Giuseppe; Singaraju, Rama Narayana; Singh, Ranbir; Singha, Subhash; Singhal, Vikas; Sinha, Bikash; Sarkar - Sinha, Tinku; Sitar, Branislav; Sitta, Mario; Skaali, Bernhard; Slupecki, Maciej; Smirnov, Nikolai; Snellings, Raimond; Snellman, Tomas Wilhelm; Soegaard, Carsten; Soltz, Ron Ariel; Song, Jihye; Song, Myunggeun; Song, Zixuan; Soramel, Francesca; Sorensen, Soren Pontoppidan; Spacek, Michal; Spiriti, Eleuterio; Sputowska, Iwona Anna; Spyropoulou-Stassinaki, Martha; Srivastava, Brijesh Kumar; Stachel, Johanna; Stan, Ionel; Stefanek, Grzegorz; Steinpreis, Matthew Donald; Stenlund, Evert Anders; Steyn, Gideon Francois; Stiller, Johannes Hendrik; Stocco, Diego; Strmen, Peter; Alarcon Do Passo Suaide, Alexandre; Sugitate, Toru; Suire, Christophe Pierre; Suleymanov, Mais Kazim Oglu; Sultanov, Rishat; Sumbera, Michal; Symons, Timothy; Szabo, Alexander; Szanto De Toledo, Alejandro; Szarka, Imrich; Szczepankiewicz, Adam; Szymanski, Maciej Pawel; Takahashi, Jun; Tanaka, Naoto; Tangaro, Marco-Antonio; Tapia Takaki, Daniel Jesus; Tarantola Peloni, Attilio; Tariq, Mohammad; Tarzila, Madalina-Gabriela; Tauro, Arturo; Tejeda Munoz, Guillermo; Telesca, Adriana; Terasaki, Kohei; Terrevoli, Cristina; Teyssier, Boris; Thaeder, Jochen Mathias; Thomas, Deepa; Tieulent, Raphael Noel; Timmins, Anthony Robert; Toia, Alberica; Trogolo, Stefano; Trubnikov, Victor; Trzaska, Wladyslaw Henryk; Tsuji, Tomoya; Tumkin, Alexandr; Turrisi, Rosario; Tveter, Trine Spedstad; Ullaland, Kjetil; Uras, Antonio; Usai, Gianluca; Utrobicic, Antonija; Vajzer, Michal; Vala, Martin; Valencia Palomo, Lizardo; Vallero, Sara; Van Der Maarel, Jasper; Van Hoorne, Jacobus Willem; Van Leeuwen, Marco; Vanat, Tomas; Vande Vyvre, Pierre; Varga, Dezso; Diozcora Vargas Trevino, Aurora; Vargyas, Marton; Varma, Raghava; Vasileiou, Maria; Vasiliev, Andrey; Vauthier, Astrid; Vechernin, Vladimir; Veen, Annelies Marianne; Veldhoen, Misha; Velure, Arild; Venaruzzo, Massimo; Vercellin, Ermanno; Vergara Limon, Sergio; Vernet, Renaud; Verweij, Marta; Vickovic, Linda; Viesti, Giuseppe; Viinikainen, Jussi Samuli; Vilakazi, Zabulon; Villalobos Baillie, Orlando; Vinogradov, Alexander; Vinogradov, Leonid; Vinogradov, Yury; Virgili, Tiziano; Vislavicius, Vytautas; Viyogi, Yogendra; Vodopyanov, Alexander; Volkl, Martin Andreas; Voloshin, Kirill; Voloshin, Sergey; Volpe, Giacomo; Von Haller, Barthelemy; Vorobyev, Ivan; Vranic, Danilo; Vrlakova, Janka; Vulpescu, Bogdan; Vyushin, Alexey; Wagner, Boris; Wagner, Jan; Wang, Hongkai; Wang, Mengliang; Wang, Yifei; Watanabe, Daisuke; Weber, Michael; Weber, Steffen Georg; Wessels, Johannes Peter; Westerhoff, Uwe; Wiechula, Jens; Wikne, Jon; Wilde, Martin Rudolf; Wilk, Grzegorz Andrzej; Wilkinson, Jeremy John; Williams, Crispin; Windelband, Bernd Stefan; Winn, Michael Andreas; Yaldo, Chris G; Yamaguchi, Yorito; Yang, Hongyan; Yang, Ping; Yano, Satoshi; Yasnopolskiy, Stanislav; Yin, Zhongbao; Yokoyama, Hiroki; Yoo, In-Kwon; Yurchenko, Volodymyr; Yushmanov, Igor; Zaborowska, Anna; Zaccolo, Valentina; Zaman, Ali; Zampolli, Chiara; Correia Zanoli, Henrique Jose; Zaporozhets, Sergey; Zarochentsev, Andrey; Zavada, Petr; Zavyalov, Nikolay; Zbroszczyk, Hanna Paulina; Zgura, Sorin Ion; Zhalov, Mikhail; Zhang, Haitao; Zhang, Xiaoming; Zhang, Yonghong; Zhao, Chengxin; Zhigareva, Natalia; Zhou, Daicui; Zhou, You; Zhou, Zhuo; Zhu, Hongsheng; Zhu, Jianhui; Zhu, Xiangrong; Zichichi, Antonino; Zimmermann, Alice; Zimmermann, Markus Bernhard; Zinovjev, Gennady; Zyzak, Maksym

    2015-08-17

    The measurement of the mass differences for systems bound by the strong force has reached a very high precision with protons and anti-protons. The extension of such measurement from (anti-)baryons to (anti-)nuclei allows one to probe any difference in the interactions between nucleons and anti-nucleons encoded in the (anti-)nuclei masses. This force is a remnant of the underlying strong interaction among quarks and gluons and can be described by effective theories, but cannot yet be directly derived from quantum chromodynamics. Here we report a measurement of the difference between the ratios of the mass and charge of deuterons (d) and anti-deuterons ($\\bar{d}$), and $^{3}{\\rm He}$ and $^3\\overline{\\rm He}$ nuclei carried out with the ALICE (A Large Ion Collider Experiment) detector in Pb-Pb collisions at a centre-of-mass energy per nucleon pair of 2.76 TeV. Our direct measurement of the mass-over-charge differences confirm CPT invariance to an unprecedented precision in the sector of light nuclei. This funda...

  13. Detection of Enhanced Central Mass-to-light Ratios in Low-mass Early-type Galaxies: Evidence for Black Holes?

    Science.gov (United States)

    Pechetti, Renuka; Seth, Anil; Cappellari, Michele; McDermid, Richard; den Brok, Mark; Mieske, Steffen; Strader, Jay

    2017-11-01

    We present dynamical measurements of the central mass-to-light ratio (M/L) of a sample of 27 low-mass early-type {{ATLAS}}3{{D}} galaxies. We consider all {{ATLAS}}3{{D}} galaxies with 9.7 text{}}M/L{{s}} are higher than dynamical {\\text{}}M/L{{s}} derived at larger radii and stellar population estimates of the galaxy centers in ˜80% of galaxies, with a median enhancement of ˜14% and a statistical significance of 3.3σ. We show that the enhancement in the central M/L is best described either by the presence of black holes in these galaxies or by radial initial mass function variations. Assuming a black hole model, we derive black hole masses for the sample of galaxies. In two galaxies, NGC 4458 and NGC 4660, the data suggest significantly overmassive black holes, while in most others only upper limits are obtained. We also show that the level of M/L enhancements we see in these early-type galaxy nuclei are consistent with the larger enhancements seen in ultracompact dwarf galaxies (UCDs), supporting the scenario where massive UCDs are created by stripping galaxies of these masses.

  14. KINETICS PROCESSES OF DEHYDRATION AND HEATING FISH DURING FRYING, DURING SEMI HOT AND HOT SMOKING

    Directory of Open Access Journals (Sweden)

    V. A. Pokholchenko

    2014-01-01

    Full Text Available Summary. Calculated methods of graphing of curves for kinetics of dehydration and fish heating during the processes of frying, semi hot smoking and hot smoking have been developed. The offered methods of calculating are based on the basic regularities of heat and mass exchanges of these processes. Based on the research of the regularities of dehydration on the kinetic curves, critical points were identified, that characterize the transition from the moisture removal with lower energy of its bond with material to the removal of one with higher energy bond, also the influence of the product shrinkage on the velocity of the moisture removal. These points are characteristic for the temperature curves as well. It’s suggested for the temperature curve to be replaced by broken line that consists of three straight lines that are crossing in points, corresponded with the critical moistures and critical temperatures. Significant amount of the experimental material of the research of the kinetics of dehydration and fish heating under different modes is shown by authors in the form of generalized dependencies. The method allows modeling the processes of heating and dehydrating of fish and choosing the most rational modes based on the calculated data. The proposed technique makes it possible to construct the curves of the kinetics of heating and dehydration kinetics in processes of roasting, semi hot and hot smoked fish, which allows to optimize a particular process, design more efficient in terms of consumption of raw materials and energy technology, as well as to create better machines or upgrade existing equipment into account the relationship of heat and mass transfer processes.

  15. Nearby Hot Stars May Change Our View of Distant Sources

    Science.gov (United States)

    Kohler, Susanna

    2017-07-01

    Nebula were thought to have formed only as the star evolved late into its lifetime, Walker and collaborators are now suggesting that all stars regardless of spectral type or evolutionary stage may be surrounded by swarms of tiny molecular clumps. Aroundstars that are hot enough, these clumps become the ionized plasma streamers that can cause interference with the light traveling to us from distant sources.Significant MassTo test this theory, Walker and collaborators explore observations of two distant radio quasars that have both exhibited intra-day variability over many years of observations. The team identified a hot A-type star near each of these two sources: J1819+3845 has Vega nearby, and PKS 1257326 has Alhakim.Locations of stars along the line of site to two distant quasars, J1819+3845 (top panel) and PKS 1257326 (bottom panel). Both have a nearby, hot star (blue markers) radially within 2 pc: Vega (z = 7.7 pc) and Alhakim (z = 18 pc), respectively. [Walker et al. 2017]By modeling the systems of the sources and stars, the authors show that the size, location, orientation, and numbers of plasma concentrations necessary to explain observations are all consistent with an environment similar to that of the Helix Nebula. Walker and collaborators find that the total mass in the molecular clumps surrounding the two stars would need to be comparable to the mass of the stars themselves.If this picture is correct, and if all stars are indeed surrounded by molecular clumps like these, then a substantial fraction of the mass of ourgalaxy could be contained in these clumps. Besides explaining distant quasar scintillation, this idea would therefore have a significant impact on our overall understanding of how mass in galaxies is distributed. More observations of twinkling quasars are the next step toward confirming this picture.CitationMark A. Walker et al 2017 ApJ 843 15. doi:10.3847/1538-4357/aa705c

  16. Theoretical light curve for the recurrent nova RS Ophiuchi - Determination of the white dwarf mass, composition, and distance

    International Nuclear Information System (INIS)

    Kato, M.

    1991-01-01

    Sequences of steady mass-loss solutions are constructed for the envelopes on a white dwarf with mass 1.33, 1.35, 1.36, 1.37, and 1.377 solar mass as models of the decay phase of novae. The envelopes are assumed to have a uniform chemical composition with X = 0.73, 0.6, 0.52, 0.44, 0.33, and 0.11 for hydrogen and Z = 0.02 for heavy elements by weight. An excellent agreement with the observed light curves of UV and optical is obtained in the models with a white dwarf mass of 1.36 solar mass with hydrogen content X = 0.52, and 1.37 solar mass with X = 0.6. The distance of RS Oph is obtained to be 1.6 kpc from the comparison between the theoretical and observed light curves. The success of this wind model is a strong indication from the theoretical point of view that RS Oph is a thermonuclear runaway event. 31 refs

  17. Uncertainty analysis for hot channel

    International Nuclear Information System (INIS)

    Panka, I.; Kereszturi, A.

    2006-01-01

    The fulfillment of the safety analysis acceptance criteria is usually evaluated by separate hot channel calculations using the results of neutronic or/and thermo hydraulic system calculations. In case of an ATWS event (inadvertent withdrawal of control assembly), according to the analysis, a number of fuel rods are experiencing DNB for a longer time and must be regarded as failed. Their number must be determined for a further evaluation of the radiological consequences. In the deterministic approach, the global power history must be multiplied by different hot channel factors (kx) taking into account the radial power peaking factors for each fuel pin. If DNB occurs it is necessary to perform a few number of hot channel calculations to determine the limiting kx leading just to DNB and fuel failure (the conservative DNBR limit is 1.33). Knowing the pin power distribution from the core design calculation, the number of failed fuel pins can be calculated. The above procedure can be performed by conservative assumptions (e.g. conservative input parameters in the hot channel calculations), as well. In case of hot channel uncertainty analysis, the relevant input parameters (k x, mass flow, inlet temperature of the coolant, pin average burnup, initial gap size, selection of power history influencing the gap conductance value) of hot channel calculations and the DNBR limit are varied considering the respective uncertainties. An uncertainty analysis methodology was elaborated combining the response surface method with the one sided tolerance limit method of Wilks. The results of deterministic and uncertainty hot channel calculations are compared regarding to the number of failed fuel rods, max. temperature of the clad surface and max. temperature of the fuel (Authors)

  18. Long-lived hot-carrier light emission and large blue shift in formamidinium tin triiodide perovskites

    OpenAIRE

    Fang, Hong-Hua; Adjokatse, Sampson; Shao, Shuyan; Even, Jacky; Loi, Maria Antonietta

    2018-01-01

    A long-lived hot carrier population is critical in order to develop working hot carrier photovoltaic devices with efficiencies exceeding the Shockley-Queisser limit. Here, we report photoluminescence from hot-carriers with unexpectedly long lifetime (a few ns) in formamidinium tin triiodide. An unusual large blue shift of the time-integrated photoluminescence with increasing excitation power (150 meV at 24 K and 75 meV at 293 K) is displayed. On the basis of the analysis of energy-resolved an...

  19. Triazolobithiophene Light Absorbing Self-Assembled Monolayers: Synthesis and Mass Spectrometry Applications

    Directory of Open Access Journals (Sweden)

    Denis Séraphin

    2011-10-01

    Full Text Available The synthesis of five light absorbing triazolobithiophenic thiols, which were utilized for producing self-assembled monolayers (SAMs on gold surfaces, is presented. The monolayer formation was monitored by cyclic voltammetry, indicating excellent surface coverage. The new triazolobithiophenic compounds exhibited an absorption maximum around 340 nm, which is close to the emission wavelength of a standard nitrogen laser. Consequently these compounds could be used to aid ionization in laser desorption mass spectrometry (MS.

  20. The giant resonances in hot nuclei. Linear response calculations

    International Nuclear Information System (INIS)

    Braghin, F.L.; Vautherin, D.; Abada, A.

    1995-01-01

    The isovector response function of hot nuclear matter is calculated using various effective Skyrme interactions. For Skyrme forces with a small effective mass the strength distribution is found to be nearly independent of temperature, and shows little collective effects. In contrast effective forces with an effective mass close to unity produce at zero temperature sizeable collective effects which disappear at temperatures of a few MeV. The relevance of these results for the saturation of the multiplicity of photons emitted by the giant dipole resonance in hot nuclei observed in recent experiments beyond T = 3 MeV is discussed. (authors). 12 refs., 3 figs

  1. Hot Deformation Behavior of Hot-Extruded AA7175 Through Hot Torsion Tests.

    Science.gov (United States)

    Lee, Se-Yeon; Jung, Taek-Kyun; Son, Hyeon-Woo; Kim, Sang-Wook; Son, Kwang-Tae; Choi, Ho-Joon; Oh, Sang-Ho; Lee, Ji-Woon; Hyun, Soong-Keun

    2018-03-01

    The hot deformation behavior of hot-extruded AA7175 was investigated with flow curves and processing maps through hot torsion tests. The flow curves and the deformed microstructures revealed that dynamic recrystallization (DRX) occurred in the hot-extruded AA7175 during hot working. The failure strain was highest at medium temperature. This was mainly influenced by the dynamic precipitation of fine rod-shaped MgZn2. The processing map determined the optimal deformation condition for the alloy during hot working.

  2. Long-lived hot-carrier light emission and large blue shift in formamidinium tin triiodide perovskites.

    Science.gov (United States)

    Fang, Hong-Hua; Adjokatse, Sampson; Shao, Shuyan; Even, Jacky; Loi, Maria Antonietta

    2018-01-16

    A long-lived hot carrier population is critical in order to develop working hot carrier photovoltaic devices with efficiencies exceeding the Shockley-Queisser limit. Here, we report photoluminescence from hot-carriers with unexpectedly long lifetime (a few ns) in formamidinium tin triiodide. An unusual large blue shift of the time-integrated photoluminescence with increasing excitation power (150 meV at 24 K and 75 meV at 293 K) is displayed. On the basis of the analysis of energy-resolved and time-resolved photoluminescence, we posit that these phenomena are associated with slow hot carrier relaxation and state-filling of band edge states. These observations are both important for our understanding of lead-free hybrid perovskites and for an eventual future development of efficient lead-free perovskite photovoltaics.

  3. Cosmological N-body simulations with generic hot dark matter

    DEFF Research Database (Denmark)

    Brandbyge, Jacob; Hannestad, Steen

    2017-01-01

    We have calculated the non-linear effects of generic fermionic and bosonic hot dark matter components in cosmological N-body simulations. For sub-eV masses, the non-linear power spectrum suppression caused by thermal free-streaming resembles the one seen for massive neutrinos, whereas for masses...

  4. Interplay of hot electrons from localized and propagating plasmons.

    Science.gov (United States)

    Hoang, Chung V; Hayashi, Koki; Ito, Yasuo; Gorai, Naoki; Allison, Giles; Shi, Xu; Sun, Quan; Cheng, Zhenzhou; Ueno, Kosei; Goda, Keisuke; Misawa, Hiroaki

    2017-10-03

    Plasmon-induced hot-electron generation has recently received considerable interest and has been studied to develop novel applications in optoelectronics, photovoltaics and green chemistry. Such hot electrons are typically generated from either localized plasmons in metal nanoparticles or propagating plasmons in patterned metal nanostructures. Here we simultaneously generate these heterogeneous plasmon-induced hot electrons and exploit their cooperative interplay in a single metal-semiconductor device to demonstrate, as an example, wavelength-controlled polarity-switchable photoconductivity. Specifically, the dual-plasmon device produces a net photocurrent whose polarity is determined by the balance in population and directionality between the hot electrons from localized and propagating plasmons. The current responsivity and polarity-switching wavelength of the device can be varied over the entire visible spectrum by tailoring the hot-electron interplay in various ways. This phenomenon may provide flexibility to manipulate the electrical output from light-matter interaction and offer opportunities for biosensors, long-distance communications, and photoconversion applications.Plasmon-induced hot electrons have potential applications spanning photodetection and photocatalysis. Here, Hoang et al. study the interplay between hot electrons generated by localized and propagating plasmons, and demonstrate wavelength-controlled polarity-switchable photoconductivity.

  5. Structure of light mass (exotic) nuclei as evidenced by scattering from hydrogen

    International Nuclear Information System (INIS)

    Amos, K.; Dortmans, P.J.

    1998-01-01

    Microscopic optical model potentials generated by full folding of realistic two-nucleon (n/N) interactions with nuclear structure specified by large basis shell model calculations have been constructed. With those (nonlocal) optical potentials, predictions of light mass nuclei-hydrogen scattering were obtained at intermediate energies (65 to 800 MeV) that agree well with observations of cross sections and analyzing powers

  6. Hot Galactic Arms Point To Vicious Cycle

    Science.gov (United States)

    2001-12-01

    NASA's Chandra X-ray Observatory has revealed the aftermath of a titanic explosion that wracked the elliptical galaxy known as NGC 4636. This eruption could be the latest episode in a cycle of violence that is triggered by gas falling into a central massive black hole. Chandra's images of NGC 4636 show spectacular symmetric arms, or arcs, of hot gas extending 25,000 light years into a huge cloud of multimillion-degree-Celsius gas that envelopes the galaxy. At a temperature of 10 million degrees, the arms are 30 percent hotter than the surrounding gas cloud. "The temperature jump, together with the symmetry and scale of the arms, suggests that we are observing the effects of a tremendous outburst that occurred in the center of the galaxy," said Christine Jones of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., lead author of a paper on these observations scheduled for publication in Astrophysical Journal Letters. "The energy of this explosion would be the equivalent of several hundred thousand supernovas." The arms appear to be the leading edges of a galaxy-sized shock wave that is racing outward at 700 kilometers per second, or 1.6 million miles per hour. At this speed, it would take 3 million years for the structures to attain their present size. Cavities detected in the hot gas cloud to the east and west of the center of the galaxy support the shockwave explanation. The authors suggest that the explosion is part of a majestic cosmic feedback process that keeps the galaxy in a state of turmoil. Over a period of a few million years, a hot gas cloud that envelops the stars in the galaxy cools and falls inward toward a central, massive black hole. The feeding of the black hole by the infalling material leads to an explosion that heats the hot gaseous envelope, starting the cycle anew. NGC 4636 NGC 4636 Background Subtracted This feedback cycle may explain one puzzling feature of the galaxy - the lack of a strong radio source of the type that is

  7. K2-140b - an eccentric 6.57 d transiting hot Jupiter in Virgo

    Science.gov (United States)

    Giles, H. A. C.; Bayliss, D.; Espinoza, N.; Brahm, R.; Blanco-Cuaresma, S.; Shporer, A.; Armstrong, D.; Lovis, C.; Udry, S.; Bouchy, F.; Marmier, M.; Jordán, A.; Bento, J.; Cameron, A. Collier; Sefako, R.; Cochran, W. D.; Rojas, F.; Rabus, M.; Jenkins, J. S.; Jones, M.; Pantoja, B.; Soto, M.; Jensen-Clem, R.; Duev, D. A.; Salama, M.; Riddle, R.; Baranec, C.; Law, N. M.

    2018-04-01

    We present the discovery of K2-140b, a P = 6.57 d Jupiter-mass (MP = 1.019 ± 0.070MJup) planet transiting a V = 12.5 (G5-spectral type) star in an eccentric orbit (e = 0.120^{+0.056}_{-0.046}) detected using a combination of K2 photometry and ground-based observations. With a radius of 1.095 ± 0.018 RJup, the planet has a bulk density of 0.726 ± 0.062 ρJup. The host star has a [Fe/H] of 0.12 ± 0.045, and from the K2 light curve, we find a rotation period for the star of 16.3 ± 0.1 d. This discovery is the 9th hot Jupiter from K2 and highlights K2's ability to detect transiting giant planets at periods slightly longer than traditional, ground-based surveys. This planet is slightly inflated, but much less than others with similar incident fluxes. These are of interest for investigating the inflation mechanism of hot Jupiters.

  8. Prediction of the light CP-even Higgs-boson mass of the MSSM. Towards the ILC precision

    International Nuclear Information System (INIS)

    Hahn, T.; Hollik, W.; Rzehak, H.

    2014-04-01

    The signal discovered in the Higgs searches at the LHC can be interpreted as the Higgs boson of the Standard Model as well as the light CP-even Higgs boson of the Minimal Supersymmetric Standard Model (MSSM). In this context the measured mass value, having already reached the level of a precision observable with an experimental accuracy of about 500 MeV, plays an important role. This precision can be improved substantially below the level of ∝50 MeV at the future International Linear Collider (ILC). Within the MSSM the mass of the light CP-even Higgs boson, M h , can directly be predicted from the other parameters of the model. The accuracy of this prediction should match the one of the experimental measurements. The relatively high experimentally observed value of the mass of about 125.6 GeV has led to many investigations where the supersymmetric (SUSY) partners of the top quark have masses in the multi-TeV range. We review the recent improvements for the prediction for M h in the MSSM for large scalar top masses. They were obtained by combining the existing fixed-order result, comprising the full one-loop and leading and subleading two-loop corrections, with a resummation of the leading and subleading logarithmic contributions from the scalar top sector to all orders. In this way for the first time a high-precision prediction for the mass of the light CP-even Higgs boson in the MSSM is possible all the way up to the multi-TeV region of the relevant supersymmetric particles. However, substantial further improvements will be needed to reach the ILC precision. The newly obtained corrections to M h are included into the code FeynHiggs.

  9. Stochastic behavior of cooling processes in hot nuclei

    International Nuclear Information System (INIS)

    de Oliveira, P.M.; Sa Martins, J.S.; Szanto de Toledo, A.

    1997-01-01

    The collapse of structure effects observed in hot nuclei is interpreted in terms of a dynamic lattice model which describes the process of nucleon (clusters) evaporation from a hot nucleus, predicting the final mass distribution. Results are compared with experimental data for the 10 B+ 9 Be and 10 B+ 10 B reactions, and indicate that the structures observed in the low-energy mass distributions in both simulation and experiment are a consequence of the competition between the residual interactions and the thermalization dissipative process. As a characteristic feature of complex evolving systems, this competition leads to long term memory during the dissipative path, the observables becoming thus insensitive to the actual microscopic interactions. copyright 1997 The American Physical Society

  10. TIDALLY DRIVEN ROCHE-LOBE OVERFLOW OF HOT JUPITERS WITH MESA

    Energy Technology Data Exchange (ETDEWEB)

    Valsecchi, Francesca; Rasio, Frederic A. [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), and Northwestern University, Department of Physics and Astronomy, Evanston, IL 60208 (United States); Rappaport, Saul [Department of Physics, and Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Marchant, Pablo [Argelander-Institut für Astronomie, Universität Bonn, Auf dem Hgel 71, D-53121 Bonn (Germany); Rogers, Leslie A., E-mail: francesca@u.northwestern.edu, E-mail: rasio@northwestern.edu, E-mail: sar@mit.edu, E-mail: pablo@astro.uni-bonn.de, E-mail: larogers@caltech.edu [Department of Astronomy and Department of Geophysics and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States)

    2015-11-10

    Many exoplanets have now been detected in orbits with ultra-short periods very close to the Roche limit. Building upon our previous work, we study the possibility that mass loss through Roche lobe overflow (RLO) may affect the evolution of these planets, and could possibly transform a hot Jupiter into a lower-mass planet (hot Neptune or super-Earth). We focus here on systems in which the mass loss occurs slowly (“stable mass transfer” in the language of binary star evolution) and we compute their evolution in detail with the binary evolution code Modules for Experiments in Stellar Astrophysics. We include the effects of tides, RLO, irradiation, and photo-evaporation (PE) of the planet, as well as the stellar wind and magnetic braking. Our calculations all start with a hot Jupiter close to its Roche limit, in orbit around a Sun-like star. The initial orbital decay and onset of RLO are driven by tidal dissipation in the star. We confirm that such a system can indeed evolve to produce lower-mass planets in orbits of a few days. The RLO phase eventually ends and, depending on the details of the mass transfer and on the planetary core mass, the orbital period can remain around a few days for several Gyr. The remnant planets have rocky cores and some amount of envelope material, which is slowly removed via PE at a nearly constant orbital period; these have properties resembling many of the observed super-Earths and sub-Neptunes. For these remnant planets, we also predict an anti-correlation between mass and orbital period; very low-mass planets (M{sub pl} ≲ 5 M{sub ⊕}) in ultra-short periods (P{sub orb} < 1 day) cannot be produced through this type of evolution.

  11. Mesonic correlation functions from light quarks and their spectral representation in hot quenched lattice QCD

    International Nuclear Information System (INIS)

    Wissel, S.

    2006-10-01

    In this thesis we investigate thermal in-medium modifications of various mesonic correlation functions by lattice simulations of Quantum Chromodynamics for light valence quark masses and vanishing chemical potential. Mesonic properties are typically extracted from spatial correlation functions. The results presented are based on quenched gauge field configurations generated with the standard Wilson plaquette gauge action. Concerning the fermionic part of the action, we use the non-perturbative O(a) improved Sheikholeslami-Wohlert as well as the truncated hypercube perfect action. Furthermore we utilize the maximum entropy method in order to determine physically relevant pole masses and to investigate thermal modifications of physical states and possible lattice artefacts in the interacting case. The analyses of pole and screening masses, dispersion relations, wave functions, decay constants and spectral functions essentially yield no significant modifications of the zero-temperature behavior up to 0.55 T c . Close to the phase transition in-medium effects seem to appear, which lead inter alia to significant differences between pole and screening masses. The decay constants are in good agreement with the experimental values. We have simulated above T c at nearly zero quark masses. At 1.24 T c , the occurrence of topological effects, a sign for the presence of a still broken U(1) A symmetry, prevent a more thorough analyses close to the phase transition. A complete continuum and infinite volume extrapolation of screening masses, guided by free lattice effective masses is done. It shows that the presence of collective phenomena at 1.5 and 3 T c cannot be explained by pure lattice artefacts. Unlike the vector meson the pion is far from being considered an unbound state. (orig.)

  12. Transportation conformity particulate matter hot-spot air quality modeling.

    Science.gov (United States)

    2013-07-01

    In light of the new development in particulate matter (PM) hot-spot regulations and Illinois Department : of Transportation (IDOT)s National Environmental Policy Act (NEPA) documentation requirements, : this project is intended to (1) perform and ...

  13. Heat and mass transfer across gas-filled enclosed spaces between a hot liquid surface and a cooled roof

    Energy Technology Data Exchange (ETDEWEB)

    Ralph, J C; Bennett, A W [Atomic Energy Research Establishment, Harwell, Oxfordshire (United Kingdom)

    1977-01-01

    A detailed knowledge is required of the amounts of sodium vapour which may be transported from the hot surface of a fast reactor coolant pool through the cover gas to cooler regions of the structure. Evaporation from the unbounded liquid surfaces of lakes and seas has been studied extensively but the heat and mass transfer mechanisms in gas-vapour mixtures which occur in enclosed spaces have received less attention. Recent work at Harwell has provided a theoretical model from which the heat and mass transfer in idealised plane cavities can be calculated. An experimental study is reported in this paper which seeks to verify the theoretical prediction. Heat and mass transfer measurements have been made on a system in which a heated water pool transfers heat and mass across a gas-filled space to a cooled horizontal cover plate. Several cover gases were used in the experiments and the results show that, provided the partial density of the vapour is low compared with that of the gas, the heat transfer mechanism is that of combined convection and radiation. The enhancement in heat transfer due to the presence of the vapour is broadly consistent with assumption of a direct analogy between heat and mass transfer neglecting condensation in the interspace. The mass transfer measurements, in which water condensing on the cooled roof was measured directly, showed for low roof temperatures an imbalance between the mass and heat transfer. This observation is consistent with the theoretical predictions that heat transfer in the convecting system should be independent of the amount of condensation and 'rain-back' within the cavity. The results of tests with helium showed that convection was entirely suppressed by the presence of the water vapour. This confirms the behaviour predicted for gas-vapour mixtures in which the vapour density is of the same order as the gas density. (author)

  14. Light baryon masses with dynamical twisted mass fermions

    Energy Technology Data Exchange (ETDEWEB)

    Alexandrou, C. [Cyprus Univ., Nicosia (Cyprus). Dept. of Physics; Baron, R. [CEA-Saclay, IRFU/Service de Physique Nucleaire, Gif-sur-Yvette (France); Blossier, B. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (DE). John von Neumann-Inst. fuer Computing NIC] (and others)

    2008-03-15

    We present results on the mass of the nucleon and the {delta} using two dynamical degenerate twisted mass quarks. The evaluation is performed at four quark masses corresponding to a pion mass in the range of about 300-600 MeV on lattices of 2.1-2.7 fm. We check for cut-off effects by evaluating these baryon masses on lattices of spatial size 2.1 fm at {beta}=3.9 and {beta}=4.05 and on a lattice of 2.4 fm at {beta}=3.8. The values we find are compatible within our statistical errors. Lattice results are extrapolated to the physical limit using continuum chiral perturbation theory. Performing a combined fit to our lattice data at {beta}=3.9 and {beta}=4.05 we find a nucleon mass of 964{+-}28(stat.){+-}8(syst.) MeV where we used the lattice spacings determined from the pion decay constant to convert to physical units. The systematic error due to the chiral extrapolation is estimated by comparing results obtained at O(p{sup 3}) and O(p{sup 4}) heavy baryon chiral perturbation theory. The nucleon mass at the physical point provides an independent determination of the lattice spacing. Using heavy baryon chiral perturbation theory at O(p{sup 3}) we find a{sub {beta}}{sub =3.9}=0.0890{+-}0.0039(stat.){+-}0.0014(syst.) fm, and a{sub {beta}}{sub =4.05}=0.0691{+-}0.0034(stat.){+-}0.0010(syst.) fm, in good agreement with the values determined from the pion decay constant. Using results from our two smaller lattices spacings at constant r0m we estimate the continuum limit and check consistency with results from the coarser lattice. Results at the continuum limit are chirally extrapolated to the physical point. Isospin violating lattice artifacts in the {delta}-system are found to be compatible with zero for the values of the lattice spacings used in this work. Performing a combined fit to our lattice data at {beta}=3.9 and {beta}=4.05 we find for the masses of the {delta}{sup ++,-} and {delta}{sup +,0} 1316{+-}60(stat.) MeV and 1330{+-}74(stat.) MeV respectively. We confirm

  15. Light baryon masses with dynamical twisted mass fermions

    International Nuclear Information System (INIS)

    Alexandrou, C.; Blossier, B.

    2008-03-01

    We present results on the mass of the nucleon and the Δ using two dynamical degenerate twisted mass quarks. The evaluation is performed at four quark masses corresponding to a pion mass in the range of about 300-600 MeV on lattices of 2.1-2.7 fm. We check for cut-off effects by evaluating these baryon masses on lattices of spatial size 2.1 fm at β=3.9 and β=4.05 and on a lattice of 2.4 fm at β=3.8. The values we find are compatible within our statistical errors. Lattice results are extrapolated to the physical limit using continuum chiral perturbation theory. Performing a combined fit to our lattice data at β=3.9 and β=4.05 we find a nucleon mass of 964±28(stat.)±8(syst.) MeV where we used the lattice spacings determined from the pion decay constant to convert to physical units. The systematic error due to the chiral extrapolation is estimated by comparing results obtained at O(p 3 ) and O(p 4 ) heavy baryon chiral perturbation theory. The nucleon mass at the physical point provides an independent determination of the lattice spacing. Using heavy baryon chiral perturbation theory at O(p 3 ) we find a β=3.9 =0.0890±0.0039(stat.)±0.0014(syst.) fm, and a β=4.05 =0.0691±0.0034(stat.)±0.0010(syst.) fm, in good agreement with the values determined from the pion decay constant. Using results from our two smaller lattices spacings at constant r0m we estimate the continuum limit and check consistency with results from the coarser lattice. Results at the continuum limit are chirally extrapolated to the physical point. Isospin violating lattice artifacts in the Δ-system are found to be compatible with zero for the values of the lattice spacings used in this work. Performing a combined fit to our lattice data at β=3.9 and β=4.05 we find for the masses of the Δ ++,- and Δ +,0 1316±60(stat.) MeV and 1330±74(stat.) MeV respectively. We confirm that in the continuum limit they are also degenerate. (orig.)

  16. Supernovae with two peaks in the optical light curve and the signature of progenitors with low-mass extended envelopes

    Energy Technology Data Exchange (ETDEWEB)

    Nakar, Ehud [Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978 (Israel); Piro, Anthony L. [Theoretical Astrophysics, California Institute of Technology, 1200 East California Boulevard, M/C 350-17, Pasadena, CA 91125 (United States)

    2014-06-20

    Early observations of supernova light curves are powerful tools for shedding light on the pre-explosion structures of their progenitors and their mass-loss histories just prior to explosion. Some core-collapse supernovae that are detected during the first days after the explosion prominently show two peaks in the optical bands, including the R and I bands, where the first peak appears to be powered by the cooling of shocked surface material and the second peak is clearly powered by radioactive decay. Such light curves have been explored in detail theoretically for SN 1993J and 2011dh, where it was found that they may be explained by progenitors with extended, low-mass envelopes. Here, we generalize these results. We first explore whether any double-peaked light curve of this type can be generated by a progenitor with a 'standard' density profile, such as a red supergiant or a Wolf-Rayet star. We show that a standard progenitor (1) cannot produce a double-peaked light curve in the R and I bands and (2) cannot exhibit a fast drop in the bolometric luminosity as is seen after the first peak. We then explore the signature of a progenitor with a compact core surrounded by extended, low-mass material. This may be a hydrostatic low-mass envelope or material ejected just prior to the explosion. We show that it naturally produces both of these features. We use this result to provide simple formulae to estimate (1) the mass of the extended material from the time of the first peak, (2) the extended material radius from the luminosity of the first peak, and (3) an upper limit on the core radius from the luminosity minimum between the two peaks.

  17. Phenomenological approach to the modelling of elliptical galaxies: The problem of the mass-to-light ratio

    Directory of Open Access Journals (Sweden)

    Samurović S.

    2007-01-01

    Full Text Available In this paper the problem of the phenomenological modelling of elliptical galaxies using various available observational data is presented. Recently, Tortora, Cardona and Piedipalumbo (2007 suggested a double power law expression for the global cumulative mass-to-light ratio of elliptical galaxies. We tested their expression on a sample of ellipticals for which we have the estimates of the mass-to-light ratio beyond ~ 3 effective radii, a region where dark matter is expected to play an important dynamical role. We found that, for all the galaxies in our sample, we have α + β > 0, but that this does not necessarily mean a high dark matter content. The galaxies with higher mass (and higher dark matter content also have higher value of α+β. It was also shown that there is an indication that the galaxies with higher value of the effective radius also have higher dark matter content. .

  18. Light and optics principles and practices

    CERN Document Server

    Al-Azzawi, Abdul

    2007-01-01

    THE NATURE OF LIGHTIntroductionThe Evolution of Light TheoryMeasurements of the Speed of LightLight SourcesThe Electromagnetic SpectrumTypes of Electromagnetic WavesProperties of LightFurther ReadingLIGHT AND SHADOWSIntroductionShadowsSolar EclipseLunar EclipseApplications of ShadowsExperimental WorkList of ReferencesAppendicesFurther ReadingTHERMAL RADIATIONIntroductionThermal RadiationLight and EnergySolar Radiation EnergyClassification of Solar CollectorsFlat-Plate CollectorsSolar Heating SystemsHot Water and Steam Generation SystemsVapour Absorption Refrigeration/Air Conditioning SystemsPh

  19. Mesonic correlation functions from light quarks and their spectral representation in hot quenched lattice QCD

    Energy Technology Data Exchange (ETDEWEB)

    Wissel, S.

    2006-10-15

    In this thesis we investigate thermal in-medium modifications of various mesonic correlation functions by lattice simulations of Quantum Chromodynamics for light valence quark masses and vanishing chemical potential. Mesonic properties are typically extracted from spatial correlation functions. The results presented are based on quenched gauge field configurations generated with the standard Wilson plaquette gauge action. Concerning the fermionic part of the action, we use the non-perturbative O(a) improved Sheikholeslami-Wohlert as well as the truncated hypercube perfect action. Furthermore we utilize the maximum entropy method in order to determine physically relevant pole masses and to investigate thermal modifications of physical states and possible lattice artefacts in the interacting case. The analyses of pole and screening masses, dispersion relations, wave functions, decay constants and spectral functions essentially yield no significant modifications of the zero-temperature behavior up to 0.55 T{sub c}. Close to the phase transition in-medium effects seem to appear, which lead inter alia to significant differences between pole and screening masses. The decay constants are in good agreement with the experimental values. We have simulated above T{sub c} at nearly zero quark masses. At 1.24 T{sub c}, the occurrence of topological effects, a sign for the presence of a still broken U(1){sub A} symmetry, prevent a more thorough analyses close to the phase transition. A complete continuum and infinite volume extrapolation of screening masses, guided by free lattice effective masses is done. It shows that the presence of collective phenomena at 1.5 and 3 T{sub c} cannot be explained by pure lattice artefacts. Unlike the vector meson the pion is far from being considered an unbound state. (orig.)

  20. Imaging Plasmon Hybridization of Fano Resonances via Hot-Electron-Mediated Absorption Mapping.

    Science.gov (United States)

    Simoncelli, Sabrina; Li, Yi; Cortés, Emiliano; Maier, Stefan A

    2018-05-04

    The inhibition of radiative losses in dark plasmon modes allows storing electromagnetic energy more efficiently than in far-field excitable bright-plasmon modes. As such, processes benefiting from the enhanced absorption of light in plasmonic materials could also take profit of dark plasmon modes to boost and control nanoscale energy collection, storage, and transfer. We experimentally probe this process by imaging with nanoscale precision the hot-electron driven desorption of thiolated molecules from the surface of gold Fano nanostructures, investigating the effect of wavelength and polarization of the incident light. Spatially resolved absorption maps allow us to show the contribution of each element of the nanoantenna in the hot-electron driven process and their interplay in exciting a dark plasmon mode. Plasmon-mode engineering allows control of nanoscale reactivity and offers a route to further enhance and manipulate hot-electron driven chemical reactions and energy-conversion and transfer at the nanoscale.

  1. Shedding light on neutrino masses with dark forces

    Energy Technology Data Exchange (ETDEWEB)

    Batell, Brian [Pittsburgh Particle Physics, Astrophysics, and Cosmology Center,Department of Physics and Astronomy, University of Pittsburgh, PA 15260 (United States); Pospelov, Maxim [Perimeter Institute for Theoretical Physics,Waterloo, ON N2J 2W9 (Canada); Department of Physics and Astronomy, University of Victoria,Victoria, BC V8P 5C2 (Canada); Shuve, Brian [SLAC National Accelerator Laboratory,2575 Sand Hill Road, Menlo Park, CA 94025 (United States)

    2016-08-08

    Heavy right-handed neutrinos, N, provide the simplest explanation for the origin of light neutrino masses and mixings. If M{sub N} is at or below the weak scale, direct experimental discovery of these states is possible at accelerator experiments such as the LHC or new dedicated beam dump experiments; in these experiments, N decays after traversing a macroscopic distance from the collision point. The experimental sensitivity to right-handed neutrinos is significantly enhanced if there is a new “dark” gauge force connecting them to the Standard Model (SM), and detection of N can be the primary discovery mode for the new dark force itself. We take the well-motivated example of a B−L gauge symmetry and analyze the sensitivity to displaced decays of N produced via the new gauge interaction in two experiments: the LHC and the proposed SHiP beam dump experiment. In the most favorable case in which the mediator can be produced on-shell and decays to right handed neutrinos (pp→X+V{sub B−L}→X+NN), the sensitivity reach is controlled by the square of the B−L gauge coupling. We demonstrate that these experiments could access neutrino parameters responsible for the observed SM neutrino masses and mixings in the most straightforward implementation of the see-saw mechanism.

  2. High-precision predictions for the light CP-even Higgs boson mass of the MSSM

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, T.; Hollik, W. [Max-Planck-Institut fuer Physik, Muenchen (Germany); Heinemeyer, S. [Instituto de Fisica de Cantabria (CSIC-UC), Santander (Spain); Rzehak, H. [Freiburg Univ. (Germany). Physikalisches Inst.; Weiglein, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2014-03-15

    For the interpretation of the signal discovered in the Higgs searches at the LHC it will be crucial in particular to discriminate between the minimal Higgs sector realised in the Standard Model (SM) and its most commonly studied extension, the Minimal Supersymmetric SM (MSSM). The measured mass value, having already reached the level of a precision observable with an experimental accuracy of about 500 MeV, plays an important role in this context. In the MSSM the mass of the light CP-even Higgs boson, M{sub h}, can directly be predicted from the other parameters of the model. The accuracy of this prediction should at least match the one of the experimental result. The relatively high mass value of about 126 GeV has led to many investigations where the scalar top quarks are in the multi-TeV range. We improve the prediction for M{sub h} in the MSSM by combining the existing fixed-order result, comprising the full one-loop and leading and subleading two-loop corrections, with a resummation of the leading and subleading logarithmic contributions from the scalar top sector to all orders. In this way for the first time a high-precision prediction for the mass of the light CP-even Higgs boson in the MSSM is possible all the way up to the multi-TeV region of the relevant supersymmetric particles. The results are included in the code FeynHiggs.

  3. Light baryon masses with dynamical twisted mass fermions

    International Nuclear Information System (INIS)

    Alexandrou, C.; Korzec, T.; Koutsou, G.; Baron, R.; Guichon, P.; Blossier, B.; Herdoiza, G.; Jansen, K.; Brinet, M.; Carbonell, J.; Drach, V.; Dimopoulos, P.; Frezzotti, R.; Farchioni, F.; Liu, Z.; Pene, O.; Michael, C.; Shindler, A.; Urbach, C.; Wenger, U.

    2008-01-01

    We present results on the mass of the nucleon and the Δ using two dynamical degenerate twisted mass quarks and the tree-level Symanzik improved gauge action. The evaluation is performed at four quark masses corresponding to a pion mass in the range of about 300-600 MeV on lattices of 2.1-2.7 fm at three lattice spacings less than 0.1 fm. We check for cutoff effects by evaluating these baryon masses on lattices of spatial size 2.1 fm at β=3.9 and β=4.05 and on a lattice of 2.4 fm at β=3.8. The values we find are compatible within our statistical errors. Lattice results are extrapolated to the physical limit using continuum chiral perturbation theory. Performing a combined fit to our lattice data at β=3.9 and β=4.05 we find a nucleon mass of 963±12(stat)±8(syst) MeV where we used the lattice spacings determined from the pion decay constant to convert to physical units. The systematic error due to the chiral extrapolation is estimated by comparing results obtained at O(p 3 ) and O(p 4 ) heavy baryon chiral perturbation theory. The nucleon mass at the physical point provides an independent determination of the lattice spacing. Using heavy baryon chiral perturbation theory at O(p 3 ) we find a β=3.9 =0.0889±0.0012(stat)±0.0014(syst) fm, and a β=4.05 =0.0691±0.0010(stat)±0.0010(syst) fm, in good agreement with the values determined from the pion decay constant. Using results from our two smaller lattices spacings at constant r 0 m π we estimate the continuum limit and check consistency with results from the coarser lattice. Results at the continuum limit are chirally extrapolated to the physical point. Isospin violating lattice artifacts in the Δ-system are found to be compatible with zero for the values of the lattice spacings used in this work. Performing a combined fit to our lattice data at β=3.9 and β=4.05 we find for the masses of the Δ ++,- and Δ +,0 1315±24(stat) MeV and 1329±30(stat) MeV, respectively. We confirm that in the continuum limit

  4. Complete orthonormal sets on the past light cone - II: Functions belonging to spin 1/2 and non-zero rest mass

    International Nuclear Information System (INIS)

    Derrick, G.H.

    1987-12-01

    This is the second of a series of papers preparing the mathematical framework for a past light cone formulation for the quantum mechanics of particles of arbitrary mass and spin. The aim of past light cone quantum theory is to define quantum states solely in terms of data accessible to an observer, i.e. information from within his current past light cone. In order to set up such a theory one needs to define on the past light cone complete orthonormal sets of functions which belong to the appropriate representation of the Poincare group. Such functions are interpreted as energy-momentum eigenfunctions. The present paper treats the case of spin 1/2 and non-zero rest mass. (author). 7 refs

  5. Material influence on hot spot distribution in the nanoparticle heterodimer on film

    Science.gov (United States)

    Chen, Fang; Huang, Yingzhou; Wei, Hua; Wang, Shuxia; Zeng, Xiping; Cao, Wenbin; Wen, Weijia

    2018-04-01

    The metal nanoparticle aggregated on film, as an effective plasma enhancement pathway, has been widely used in various surface plasmon-related fields. In this study, the hot spots on the metal nanoparticle dimer composed of different materials (Agsbnd Au, Agsbnd Pd, and Agsbnd Cu) on metal (Au) film were investigated with finite element method. Based on the results, the hot spot distribution affected by the material can be confirmed by the electric field distribution of the metal nanoparticle dimer on the film. The aggregation effects of Au and Ag nanoparticles in Ausbnd Ag dimer system are not significant. However, for the Pdsbnd Ag dimer system, the hot spot aggregation effect is slightly larger than that of the Pd nanoparticle under the Ag nanoparticle. Besides, the non-uniform hot spots would bring about the light focusing phenomenon that the light intensity under Ag nanoparticle is almost 100 times greater than that under Cu nanoparticle in Agsbnd Cu dimer system. These results were further confirmed by the surface charge distribution, and analyzed based on the plasmonic hybridization theory. The data about the nanoparticle dimer on the dielectric (Si) film demonstrate the importance of induced image charges on the film surface in such a light focusing phenomenon. Our findings can enhance the understanding of the surface plasmon coupling in different materials, which may have great application prospects in surface plasmon-related fields, such as SERS, plasmonic enhanced solar cell, and plasmonic sensoring, etc.

  6. Effects of Dim Light at Night on Food Intake and Body Mass in Developing Mice

    OpenAIRE

    Ciss?, Yasmine M.; Peng, Juan; Nelson, Randy J.

    2017-01-01

    Appropriately timed light is critical for circadian organization; exposure to dim light at night (dLAN) disrupts temporal organization of endogenous biological timing. Exposure to dLAN in adult mice is associated with elevated body mass and changes in metabolism putatively driven by voluntary changes in the time of food intake. We predicted that exposure of young mice to LAN could affect adult metabolic function. At 3 weeks (Experiment 1) or 5 weeks (Experiment 2) of age, mice were either mai...

  7. Solar 'hot spots' are still hot

    Science.gov (United States)

    Bai, Taeil

    1990-01-01

    Longitude distributions of solar flares are not random but show evidence for active zones (or hot spots) where flares are concentrated. According to a previous study, two hot spots in the northern hemisphere, which rotate with a synodic period of about 26.72 days, produced the majority of major flares, during solar cycles 20 and 21. The more prominent of these two hot spots is found to be still active during the rising part of cycle 22, producing the majority of northern hemisphere major flares. The synodic rotation period of this hot spot is 26.727 + or - 0.007 days. There is also evidence for hot spots in the southern hemisphere. Two hot spots separated by 180 deg are found to rotate with a period of 29.407 days, with one of them having persisted in the same locations during cycles 19-22 and the other, during cycles 20-22.

  8. Gap-plasmon based broadband absorbers for enhanced hot-electron and photocurrent generation

    DEFF Research Database (Denmark)

    Lu, Yuhua; Dong, Wen; Chen, Zhuo

    2016-01-01

    Plasmonic hot-electron generation has recently come into focus as a new scheme for solar energy conversion. So far, however, due to the relatively narrow bandwidth of the surface plasmon resonances and the insufficient resonant light absorption, most of plasmonic photocatalysts show narrow......-band spectral responsivities and small solar energy conversion efficiencies. Here we experimentally demonstrate that a three-layered nanostructure, consisting of a monolayer gold-nanoparticles and a gold film separated by a TiO2 gap layer (Au-NPs/TiO2/Au-film), is capable of near-completely absorbing light...... within the whole visible region. We show that the Au-NPs/TiO2/Au-film device can take advantage of such strong and broadband light absorption to enhance the generation of hot electrons and thus the photocurrent under visible irradiation. As compared to conventional plasmonic photocatalysts such as Au...

  9. Evolutionary effects of mass loss in low-mass stars

    International Nuclear Information System (INIS)

    Renzini, A.

    1981-01-01

    The effects of mass loss on the evolution of low-mass stars (actual mass smaller than 1.4 solar masses) are reviewed. The case of globular cluster stars is discussed in some detail, and it is shown that evolutionary theory sets quite precise limits to the mass-loss rate in population II red giants. The effects of mass loss on the final evolutionary stages of stars producing white dwarfs is also discussed. In particular, the interaction of the wind from the hot central star with the surrounding planetary nebula is considered. Finally, the problem of the origin of hydrogen-deficient stars is briefly discussed. (Auth.)

  10. Coral bleaching and ocean ''hot spots''

    Energy Technology Data Exchange (ETDEWEB)

    Goreau, T.J. (Global Coral Reef Alliance, Chappaqua, NY (United States)); Hayes, R.L. (Howard Univ., Washington, DC (United States). College of Medicine)

    1994-05-01

    Global sea-surface temperature maps show that mass coral-reef bleaching episodes between 1983 and 1991 followed positive anomalies more than 1 deg C above long-term monthly averages (''hot spots'') during the preceding warm season. Irregular formation, movement, and disappearance of hot spots make their detailed long-term prediction impossible, but they can be tracked in real time from satellite data. Monitoring of ocean hot spots and of coral bleaching is needed if the Framework Convention of Climate Change is to meet its goal of protecting the most temperature sensitive ecosystems. 47 refs, 3 figs

  11. THE DETECTION OF A HOT MOLECULAR CORE IN THE LARGE MAGELLANIC CLOUD WITH ALMA

    International Nuclear Information System (INIS)

    Shimonishi, Takashi; Onaka, Takashi; Kawamura, Akiko; Aikawa, Yuri

    2016-01-01

    We report the first detection of a hot molecular core outside our Galaxy based on radio observations with ALMA toward a high-mass young stellar object (YSO) in a nearby low metallicity galaxy, the Large Magellanic Cloud (LMC). Molecular emission lines of CO, C 17 O, HCO + , H 13 CO + , H 2 CO, NO, SiO, H 2 CS, 33 SO, 32 SO 2 , 34 SO 2 , and 33 SO 2 are detected from a compact region (∼0.1 pc) associated with a high-mass YSO, ST11. The temperature of molecular gas is estimated to be higher than 100 K based on rotation diagram analysis of SO 2 and 34 SO 2 lines. The compact source size, warm gas temperature, high density, and rich molecular lines around a high-mass protostar suggest that ST11 is associated with a hot molecular core. We find that the molecular abundances of the LMC hot core are significantly different from those of Galactic hot cores. The abundances of CH 3 OH, H 2 CO, and HNCO are remarkably lower compared to Galactic hot cores by at least 1–3 orders of magnitude. We suggest that these abundances are characterized by the deficiency of molecules whose formation requires the hydrogenation of CO on grain surfaces. In contrast, NO shows a high abundance in ST11 despite the notably low abundance of nitrogen in the LMC. A multitude of SO 2 and its isotopologue line detections in ST11 imply that SO 2 can be a key molecular tracer of hot core chemistry in metal-poor environments. Furthermore, we find molecular outflows around the hot core, which is the second detection of an extragalactic protostellar outflow. In this paper, we discuss the physical and chemical characteristics of a hot molecular core in the low metallicity environment.

  12. Coronal mass ejection kinematics deduced from white light (Solar Mass Ejection Imager) and radio (Wind/WAVES) observations

    Science.gov (United States)

    Reiner, M. J.; Jackson, B. V.; Webb, D. F.; Mizuno, D. R.; Kaiser, M. L.; Bougeret, J.-L.

    2005-09-01

    White-light and radio observations are combined to deduce the coronal and interplanetary kinematics of a fast coronal mass ejection (CME) that was ejected from the Sun at about 1700 UT on 2 November 2003. The CME, which was associated with an X8.3 solar flare from W56°, was observed by the Mauna Loa and Solar and Heliospheric Observatory (SOHO) Large-Angle Spectrometric Coronograph (LASCO) coronagraphs to 14 R⊙. The measured plane-of-sky speed of the LASCO CME was 2600 km s-1. To deduce the kinematics of this CME, we use the plane-of-sky white light observations from both the Solar Mass Ejection Imager (SMEI) all-sky camera on board the Coriolis spacecraft and the SOHO/LASCO coronagraph, as well as the frequency drift rate of the low-frequency radio data and the results of the radio direction-finding analysis from the WAVES experiment on the Wind spacecraft. In agreement with the in situ observations for this event, we find that both the white light and radio observations indicate that the CME must have decelerated significantly beginning near the Sun and continuing well into the interplanetary medium. More specifically, by requiring self-consistency of all the available remote and in situ data, together with a simple, but not unreasonable, assumption about the general characteristic of the CME deceleration, we were able to deduce the radial speed and distance time profiles for this CME as it propagated from the Sun to 1 AU. The technique presented here, which is applicable to mutual SMEI/WAVES CME events, is expected to provide a more complete description and better quantitative understanding of how CMEs propagate through interplanetary space, as well as how the radio emissions, generated by propagating CME/shocks, relate to the shock and CME. This understanding can potentially lead to more accurate predictions for the onset times of space weather events, such as those that were observed during this unique period of intense solar activity.

  13. LIGHT CURVES OF CORE-COLLAPSE SUPERNOVAE WITH SUBSTANTIAL MASS LOSS USING THE NEW OPEN-SOURCE SUPERNOVA EXPLOSION CODE (SNEC)

    International Nuclear Information System (INIS)

    Morozova, Viktoriya; Renzo, Mathieu; Ott, Christian D.; Clausen, Drew; Couch, Sean M.; Ellis, Justin; Roberts, Luke F.; Piro, Anthony L.

    2015-01-01

    We present the SuperNova Explosion Code (SNEC), an open-source Lagrangian code for the hydrodynamics and equilibrium-diffusion radiation transport in the expanding envelopes of supernovae. Given a model of a progenitor star, an explosion energy, and an amount and distribution of radioactive nickel, SNEC generates the bolometric light curve, as well as the light curves in different broad bands assuming blackbody emission. As a first application of SNEC, we consider the explosions of a grid of 15 M ⊙ (at zero-age main sequence, ZAMS) stars whose hydrogen envelopes are stripped to different extents and at different points in their evolution. The resulting light curves exhibit plateaus with durations of ∼20–100 days if ≳1.5–2 M ⊙ of hydrogen-rich material is left and no plateau if less hydrogen-rich material is left. If these shorter plateau lengths are not seen for SNe IIP in nature, it suggests that, at least for ZAMS masses ≲20 M ⊙ , hydrogen mass loss occurs as an all or nothing process. This perhaps points to the important role binary interactions play in generating the observed mass-stripped supernovae (i.e., Type Ib/c events). These light curves are also unlike what is typically seen for SNe IIL, arguing that simply varying the amount of mass loss cannot explain these events. The most stripped models begin to show double-peaked light curves similar to what is often seen for SNe IIb, confirming previous work that these supernovae can come from progenitors that have a small amount of hydrogen and a radius of ∼500 R ⊙

  14. LIGHT CURVES OF CORE-COLLAPSE SUPERNOVAE WITH SUBSTANTIAL MASS LOSS USING THE NEW OPEN-SOURCE SUPERNOVA EXPLOSION CODE (SNEC)

    Energy Technology Data Exchange (ETDEWEB)

    Morozova, Viktoriya; Renzo, Mathieu; Ott, Christian D.; Clausen, Drew; Couch, Sean M.; Ellis, Justin; Roberts, Luke F. [TAPIR, Walter Burke Institute for Theoretical Physics, MC 350-17, California Institute of Technology, Pasadena, CA 91125 (United States); Piro, Anthony L., E-mail: morozvs@tapir.caltech.edu [Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101 (United States)

    2015-11-20

    We present the SuperNova Explosion Code (SNEC), an open-source Lagrangian code for the hydrodynamics and equilibrium-diffusion radiation transport in the expanding envelopes of supernovae. Given a model of a progenitor star, an explosion energy, and an amount and distribution of radioactive nickel, SNEC generates the bolometric light curve, as well as the light curves in different broad bands assuming blackbody emission. As a first application of SNEC, we consider the explosions of a grid of 15 M{sub ⊙} (at zero-age main sequence, ZAMS) stars whose hydrogen envelopes are stripped to different extents and at different points in their evolution. The resulting light curves exhibit plateaus with durations of ∼20–100 days if ≳1.5–2 M{sub ⊙} of hydrogen-rich material is left and no plateau if less hydrogen-rich material is left. If these shorter plateau lengths are not seen for SNe IIP in nature, it suggests that, at least for ZAMS masses ≲20 M{sub ⊙}, hydrogen mass loss occurs as an all or nothing process. This perhaps points to the important role binary interactions play in generating the observed mass-stripped supernovae (i.e., Type Ib/c events). These light curves are also unlike what is typically seen for SNe IIL, arguing that simply varying the amount of mass loss cannot explain these events. The most stripped models begin to show double-peaked light curves similar to what is often seen for SNe IIb, confirming previous work that these supernovae can come from progenitors that have a small amount of hydrogen and a radius of ∼500 R{sub ⊙}.

  15. Solar hot spots are still hot

    International Nuclear Information System (INIS)

    Bai, T.

    1990-01-01

    Longitude distributions of solar flares are not random but show evidence for active zones (or hot spots) where flares are concentrated. According to a previous study, two hot spots in the northern hemisphere, which rotate with a synodic period of about 26.72 days, produced the majority of major flares, during solar cycles 20 and 21. The more prominent of these two hot spots is found to be still active during the rising part of cycle 22, producing the majority of northern hemisphere major flares. The synodic rotation period of this hot spot is 26.727 + or - 0.007 days. There is also evidence for hot spots in the southern hemisphere. Two hot spots separated by 180 deg are found to rotate with a period of 29.407 days, with one of them having persisted in the same locations during cycles 19-22 and the other, during cycles 20-22. 14 refs

  16. Hot subluminous stars: Highlights from the MUCHFUSS and Kepler missions

    Directory of Open Access Journals (Sweden)

    Geier S.

    2013-03-01

    Full Text Available Research into hot subdwarf stars is progressing rapidly. We present recent important discoveries. First we review the knowledge about magnetic fields in hot subdwarfs and highlight the first detection of a highly-magnetic, helium-rich sdO star. We briefly summarize recent discoveries based on Kepler light curves and finally introduce the closest known sdB+WD binary discovered by the MUCHFUSS project and discuss its relevance as a progenitor of a double-detonation type Ia supernova.

  17. Auger-generated hot carrier current in photo-excited forward biased single quantum well blue light emitting diodes

    Science.gov (United States)

    Espenlaub, Andrew C.; Alhassan, Abdullah I.; Nakamura, Shuji; Weisbuch, Claude; Speck, James S.

    2018-04-01

    We report on measurements of the photo-modulated current-voltage and electroluminescence characteristics of forward biased single quantum well, blue InGaN/GaN light emitting diodes with and without electron blocking layers. Low intensity resonant optical excitation of the quantum well was observed to induce an additional forward current at constant forward diode bias, in contrast to the usual sense of the photocurrent in photodiodes and solar cells, as well as an increased electroluminescence intensity. The presence of an electron blocking layer only slightly decreased the magnitude of the photo-induced current at constant forward bias. Photo-modulation at constant forward diode current resulted in a reduced diode bias under optical excitation. We argue that this decrease in diode bias at constant current and the increase in forward diode current at constant applied bias can only be due to additional hot carriers being ejected from the quantum well as a result of an increased Auger recombination rate within the quantum well.

  18. Intense, ultrashort light and dense, hot matter

    Indian Academy of Sciences (India)

    This article presents an overview of the physics and applications of the interaction of high intensity laser light with matter. It traces the crucial advances that have occurred over the past few decades in laser technology and nonlinear optics and then discusses physical phenomena that occur in intense laser fields and their ...

  19. HOT 2015

    DEFF Research Database (Denmark)

    Hannibal, Sara Stefansen

    2016-01-01

    HOT samler og formidler 21 literacykyndiges bud på, hvad der er hot, og hvad der bør være hot inden for literacy – og deres begrundelser for disse bud.......HOT samler og formidler 21 literacykyndiges bud på, hvad der er hot, og hvad der bør være hot inden for literacy – og deres begrundelser for disse bud....

  20. Single-particle measurements of bouncing particles and in situ collection efficiency from an airborne aerosol mass spectrometer (AMS) with light-scattering detection

    Science.gov (United States)

    Liao, Jin; Brock, Charles A.; Murphy, Daniel M.; Sueper, Donna T.; Welti, André; Middlebrook, Ann M.

    2017-10-01

    A light-scattering module was coupled to an airborne, compact time-of-flight aerosol mass spectrometer (LS-AMS) to investigate collection efficiency (CE) while obtaining nonrefractory aerosol chemical composition measurements during the Southeast Nexus (SENEX) campaign. In this instrument, particles scatter light from an internal laser beam and trigger saving individual particle mass spectra. Nearly all of the single-particle data with mass spectra that were triggered by scattered light signals were from particles larger than ˜ 280 nm in vacuum aerodynamic diameter. Over 33 000 particles are characterized as either prompt (27 %), delayed (15 %), or null (58 %), according to the time and intensity of their total mass spectral signals. The particle mass from single-particle spectra is proportional to that derived from the light-scattering diameter (dva-LS) but not to that from the particle time-of-flight (PToF) diameter (dva-MS) from the time of the maximum mass spectral signal. The total mass spectral signal from delayed particles was about 80 % of that from prompt ones for the same dva-LS. Both field and laboratory data indicate that the relative intensities of various ions in the prompt spectra show more fragmentation compared to the delayed spectra. The particles with a delayed mass spectral signal likely bounced off the vaporizer and vaporized later on another surface within the confines of the ionization source. Because delayed particles are detected by the mass spectrometer later than expected from their dva-LS size, they can affect the interpretation of particle size (PToF) mass distributions, especially at larger sizes. The CE, measured by the average number or mass fractions of particles optically detected that had measurable mass spectra, varied significantly (0.2-0.9) in different air masses. The measured CE agreed well with a previous parameterization when CE > 0.5 for acidic particles but was sometimes lower than the minimum parameterized CE of 0.5.

  1. Hadron spectrum, quark masses and decay constants from light overlap fermions on large lattices

    International Nuclear Information System (INIS)

    Galletly, D.; Horsley, R.; Streuer, T.; Freie Univ. Berlin

    2006-07-01

    We present results from a simulation of quenched overlap fermions with Luescher-Weisz gauge field action on lattices up to 24 3 48 and for pion masses down to ∼250 MeV. Among the quantities we study are the pion, rho and nucleon masses, the light and strange quark masses, and the pion decay constant. The renormalization of the scalar and axial vector currents is done nonperturbatively in the RI-MOM scheme. The simulations are performed at two different lattice spacings, a ∼0.1 fm and ∼0.15 fm, and on two different physical volumes, to test the scaling properties of our action and to study finite volume effects. We compare our results with the predictions of chiral perturbation theory and compute several of its low-energy constants. The pion mass is computed in sectors of fixed topology as well. (orig.)

  2. Hadron spectrum, quark masses and decay constants from light overlap fermions on large lattices

    Energy Technology Data Exchange (ETDEWEB)

    Galletly, D.; Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics; Guertler, M. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Perlt, H.; Schiller, A. [Leipzig Univ. (Germany). Inst. fuer Theoretische Physik; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Division, Dept. of Mathematical Sciences; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Streuer, T. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC]|[Freie Univ. Berlin (Germany). Inst. fuer Theoretische Physik

    2006-07-15

    We present results from a simulation of quenched overlap fermions with Luescher-Weisz gauge field action on lattices up to 24{sup 3} 48 and for pion masses down to {approx}250 MeV. Among the quantities we study are the pion, rho and nucleon masses, the light and strange quark masses, and the pion decay constant. The renormalization of the scalar and axial vector currents is done nonperturbatively in the RI-MOM scheme. The simulations are performed at two different lattice spacings, a {approx}0.1 fm and {approx}0.15 fm, and on two different physical volumes, to test the scaling properties of our action and to study finite volume effects. We compare our results with the predictions of chiral perturbation theory and compute several of its low-energy constants. The pion mass is computed in sectors of fixed topology as well. (orig.)

  3. Closed bioregenerative life support systems: Applicability to hot deserts

    Science.gov (United States)

    Polyakov, Yuriy S.; Musaev, Ibrahim; Polyakov, Sergey V.

    2010-09-01

    Water scarcity in hot deserts, which cover about one-fifth of the Earth's land area, along with rapid expansion of hot deserts into arable lands is one of the key global environmental problems. As hot deserts are extreme habitats characterized by the availability of solar energy with a nearly complete absence of organic life and water, space technology achievements in designing closed ecological systems may be applicable to the design of sustainable settlements in the deserts. This review discusses the key space technology findings for closed biogenerative life support systems (CBLSS), which can simultaneously produce food, water, nutrients, fertilizers, process wastes, and revitalize air, that can be applied to hot deserts. Among them are the closed cycle of water and the acceleration of the cycling times of carbon, biogenic compounds, and nutrients by adjusting the levels of light intensity, temperature, carbon dioxide, and air velocity over plant canopies. Enhanced growth of algae and duckweed at higher levels of carbon dioxide and light intensity can be important to provide complete water recycling and augment biomass production. The production of fertilizers and nutrients can be enhanced by applying the subsurface flow wetland technology and hyper-thermophilic aerobic bacteria for treating liquid and solid wastes. The mathematical models, optimization techniques, and non-invasive measuring techniques developed for CBLSS make it possible to monitor and optimize the performance of such closed ecological systems. The results of long-duration experiments performed in BIOS-3, Biosphere 2, Laboratory Biosphere, and other ground-based closed test facilities suggest that closed water cycle can be achieved in hot-desert bioregenerative systems using the pathways of evapotranspiration, condensation, and biological wastewater treatment technologies. We suggest that the state of the art in the CBLSS design along with the possibility of using direct sunlight for

  4. Hot and Hypoxic Environments Inhibit Simulated Soccer Performance and Exacerbate Performance Decrements When Combined

    Science.gov (United States)

    Aldous, Jeffrey W. F.; Chrismas, Bryna C. R.; Akubat, Ibrahim; Dascombe, Ben; Abt, Grant; Taylor, Lee

    2016-01-01

    The effects of heat and/or hypoxia have been well-documented in match-play data. However, large match-to-match variation for key physical performance measures makes environmental inferences difficult to ascertain from soccer match-play. Therefore, the present study aims to investigate the hot (HOT), hypoxic (HYP), and hot-hypoxic (HH) mediated-decrements during a non-motorized treadmill based soccer-specific simulation. Twelve male University soccer players completed three familiarization sessions and four randomized crossover experimental trials of the intermittent Soccer Performance Test (iSPT) in normoxic-temperate (CON: 18°C 50% rH), HOT (30°C; 50% rH), HYP (1000 m; 18°C 50% rH), and HH (1000 m; 30°C; 50% rH). Physical performance and its performance decrements, body temperatures (rectal, skin, and estimated muscle temperature), heart rate (HR), arterial blood oxygen saturation (SaO2), perceived exertion, thermal sensation (TS), body mass changes, blood lactate, and plasma volume were all measured. Performance decrements were similar in HOT and HYP [Total Distance (−4%), High-speed distance (~−8%), and variable run distance (~−12%) covered] and exacerbated in HH [total distance (−9%), high-speed distance (−15%), and variable run distance (−15%)] compared to CON. Peak sprint speed, was 4% greater in HOT compared with CON and HYP and 7% greater in HH. Sprint distance covered was unchanged (p > 0.05) in HOT and HYP and only decreased in HH (−8%) compared with CON. Body mass (−2%), temperatures (+2–5%), and TS (+18%) were altered in HOT. Furthermore, SaO2 (−8%) and HR (+3%) were changed in HYP. Similar changes in body mass and temperatures, HR, TS, and SaO2 were evident in HH to HOT and HYP, however, blood lactate (p physical performance during iSPT. Future interventions should address the increases in TS and body temperatures, to attenuate these decrements on soccer performance. PMID:26793122

  5. From light to baryonic mass: the effect of the stellar mass-to-light ratio on the Baryonic Tully-Fisher relation

    Science.gov (United States)

    Ponomareva, Anastasia A.; Verheijen, Marc A. W.; Papastergis, Emmanouil; Bosma, Albert; Peletier, Reynier F.

    2018-03-01

    In this paper, we investigate the statistical properties of the Baryonic Tully-Fisher relation (BTFr) for a sample of 32 galaxies with accurate distances based on Cepheïds and/or TRGB stars. We make use of homogeneously analysed photometry in 18 bands ranging from the far-ultraviolet to 160 μm, allowing us to investigate the effect of the inferred stellar mass-to-light ratio (ϒ⋆) on the statistical properties of the BTFr. Stellar masses of our sample galaxies are derived with four different methods based on full SED fitting, studies of stellar dynamics, near-infrared colours, and the assumption of the same Υ_{\\star }^{[3.6]} for all galaxies. In addition, we use high-quality, resolved H I kinematics to study the BTFr based on three kinematic measures: Wi_{50} from the global H I profile, and Vmax and Vflat from the rotation curve. We find the intrinsic perpendicular scatter, or tightness, of our BTFr to be σ⊥ = 0.026 ± 0.013 dex, consistent with the intrinsic tightness of the 3.6 μm luminosity-based Tully-Fisher relation (TFr). However, we find the slope of the BTFr to be 2.99 ± 0.2 instead of 3.7 ± 0.1 for the luminosity-based TFr at 3.6 μm. We use our BTFr to place important observational constraints on theoretical models of galaxy formation and evolution by making comparisons with theoretical predictions based on either the Λ cold dark matter framework or modified Newtonian dynamics.

  6. Mass differences of light hadron isomultiplets

    International Nuclear Information System (INIS)

    Palladino, B.E.; Ferreira, P.L.

    1989-01-01

    Mass differences of low-lying, non-strange, hadron isomultiplets are investigated in the framework of a relativistic, independent quark potential model, implemented by center-of-mass, one-gluon-exchange and pion-cloud corrections. The introduction of pionic self-energy corrections with non-degenerate intermediate states is instrumental in our analysis, playing also a fundamental role for a successful description of the ρ-ω mass splitting. The effect of the supersposition of all these corrections is discussed in some detail for the p-n, Π + -Π 0 , ρ + -ρ 0 and Δ ++ -Δ 0 mass differences. The corresponding hadronic masses are also calculated with suitable values for the hardronic sizes and quark masses. (author) [pt

  7. HotRegion: a database of predicted hot spot clusters.

    Science.gov (United States)

    Cukuroglu, Engin; Gursoy, Attila; Keskin, Ozlem

    2012-01-01

    Hot spots are energetically important residues at protein interfaces and they are not randomly distributed across the interface but rather clustered. These clustered hot spots form hot regions. Hot regions are important for the stability of protein complexes, as well as providing specificity to binding sites. We propose a database called HotRegion, which provides the hot region information of the interfaces by using predicted hot spot residues, and structural properties of these interface residues such as pair potentials of interface residues, accessible surface area (ASA) and relative ASA values of interface residues of both monomer and complex forms of proteins. Also, the 3D visualization of the interface and interactions among hot spot residues are provided. HotRegion is accessible at http://prism.ccbb.ku.edu.tr/hotregion.

  8. Role of hydrodynamic instability growth in hot-spot mass gain and fusion performance of inertial confinement fusion implosions

    International Nuclear Information System (INIS)

    Srinivasan, Bhuvana; Tang, Xian-Zhu

    2014-01-01

    In an inertial confinement fusion target, energy loss due to thermal conduction from the hot-spot will inevitably ablate fuel ice into the hot-spot, resulting in a more massive but cooler hot-spot, which negatively impacts fusion yield. Hydrodynamic mix due to Rayleigh-Taylor instability at the gas-ice interface can aggravate the problem via an increased gas-ice interfacial area across which energy transfer from the hot-spot and ice can be enhanced. Here, this mix-enhanced transport effect on hot-spot fusion-performance degradation is quantified using contrasting 1D and 2D hydrodynamic simulations, and its dependence on effective acceleration, Atwood number, and ablation speed is identified

  9. Mass and Cross Section Measurements of light-flavored Squarks at CLIC

    CERN Document Server

    WEUSTE, L.

    2011-01-01

    We present a study of the prospects for the measurement of TeV-scale light-flavored right-squark masses and and the production cross sections at a 3 TeV e+e- collider based on CLIC technology. The analysis, performed in the framework of the CLIC Conceptual Design Report, is based on full Geant4 simulations of the CLIC ILD detector concept, including standard model physics background and machine related hadronic background from two-photon processes. The events were reconstructed using particle flow event reconstruction, and the mass and cross sections were obtained from a template fit built from generator-level simulations with smearing to parametrize the detector response. For an integrated luminosity of 2 ab^-1, a statistical precision of 5.9 GeV, corresponding to 0.52%, was obtained for unseparated first and second generation right squarks. For the combined cross section, a precision of 0.07 fb, corresponding to 5%, was obtained.

  10. Binaries discovered by the SPY survey VI. Discovery of a low mass companion to the hot subluminous planetary nebula central star EGB5-a recently ejected common envelope?

    OpenAIRE

    Geier, S.; Napiwotzki, R.; Heber, U.; Nelemans, G.A.

    2011-01-01

    Hot subdwarf B stars (sdBs) in close binary systems are assumed to be formed via common envelope ejection. According to theoretical models, the amount of energy and angular momentum deposited in the common envelope scales with the mass of the companion. That low mass companions near or below the core hydrogen-burning limit are able to trigger the ejection of this envelope is well known. The currently known systems have very short periods $\\simeq0.1-0.3\\,{\\rm d}$. Here we report the discovery ...

  11. Exploring molecular complexity with ALMA (EMoCA): Detection of three new hot cores in Sagittarius B2(N)

    Science.gov (United States)

    Bonfand, M.; Belloche, A.; Menten, K. M.; Garrod, R. T.; Müller, H. S. P.

    2017-08-01

    Context. The Sagittarius B2 molecular cloud contains several sites forming high-mass stars. Sgr B2(N) is one of its main centers of activity. It hosts several compact and ultra-compact HII regions, as well as two known hot molecular cores (Sgr B2(N1) and Sgr B2(N2)) in the early stage of the high-mass star formation process, where complex organic molecules (COMs) are detected in the gas phase. Aims: Our goal is to use the high sensitivity of the Atacama Large Millimeter/submillimeter Array (ALMA) to characterize the hot core population in Sgr B2(N) and thereby shed new light on the star formation process in this star-forming region. Methods: We use a complete 3 mm spectral line survey conducted with ALMA to search for faint hot cores in the Sgr B2(N) region. The chemical composition of the detected sources and the column densities are derived by modeling the whole spectra under the assumption of local thermodynamic equilibrium. Population diagrams are constructed to fit rotational temperatures. Integrated intensity maps are produced to derive the peak position and fit the size of each molecule's emission distribution. The kinematic structure of the hot cores is investigated by analyzing the line wing emission of typical outflow tracers. The H2 column densities are computed from ALMA and SMA continuum emission maps. Results: We report the discovery of three new hot cores in Sgr B2(N) that we call Sgr B2(N3), Sgr B2(N4), and Sgr B2(N5). The three sources are associated with class II methanol masers, well known tracers of high-mass star formation, and Sgr B2(N5), also with a UCHII region. Their H2 column densities are found to be between approximately 16 and 36 times lower than the one of the main hot core Sgr B2(N1). The spectra of these new hot cores have spectral line densities of 11 up to 31 emission lines per GHz above the 7σ level, assigned to 22-25 molecules plus 13-20 less abundant isotopologs. We derive rotational temperatures of approximately 140-180 K for

  12. Sea quark contribution to the dynamical mass and light quark content of a nucleon

    International Nuclear Information System (INIS)

    Singh, J.P.

    1995-01-01

    We calculate the flavor mixing in the wave function of a light valence quark. For this, we use the idea of dynamical symmetry breaking. A sea quark of a different flavor may appear through the vacuum polarization of a gluon propagator which appears in the gap equation for the dynamical mass. We have also used the fact that any one of these quark lines may undergo condensation. The dependence of the dynamical mass, generated in this way, on the sea quark mass up to quadratic terms has been retained. The momentum dependence is like 1/p 4 , in contrast with the 1/p 2 kind of dependence which occurs for the leading term of the dynamical mass in the subasymptotic region. The extension of the result to the ''mass shell'' yields σ πN =53--54 MeV for the pion-nucleon σ term and m s left-angle p|bar ss|p right-angle=122--264 meV for the strange quark contribution to the proton mass, for different values of parameters. These are in reasonable agreement with current phenomenological estimates of these quantities

  13. Very low velocity ion slowing down in binary ionic mixtures: Charge- and mass-asymmetry effects

    Directory of Open Access Journals (Sweden)

    Patrice Fromy

    2010-10-01

    Full Text Available A binary ionic mixture (BIM in dense and hot plasmas of specific concern for inertial confinement fusion and white dwarf crust is considered as a target for incoming light ions with a velocity smaller than the thermal electron one. The given target stopping power, mostly BIM monitored, is specifically studied in terms of charge and mass asymmetry in its ionic component. The classical plasma target is worked out within a dielectric framework, and scanned with respect to density, temperature, and BIM composition.

  14. Hot-Dip Coating of Lead-free Aluminum on Steel Substrates with Ultrasonic Vibration

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Hot-dip coating has been practically employed in manufacturing zinc alloy coated steel sheets. However, it is difficult to coat aluminum alloy on a bulky steel substrate without sufficient preheating, because a rapidly solidified layer containing gas babbles is formed on a substrate surface. A variety of iron-aluminides are also formed at the interface of a steel and aluminum hot-dip coating system, which is the main difficulty in joining of steel with aluminum. Ultrasonic vibration was applied to a steel substrate during hot-dip coating of aluminum alloy to control a rapidly solidified layer and a brittle reaction layer. Hot dipping of columnar steel substrates into molten aluminum alloy (Al-2.7 mass fraction Si-4.6 mass fraction Sn) was carried out through the use of a Langevin oscillator with resonant frequency of 19.5 kHz. The application of ultrasonic vibration is quite effective to control a rapidly solidified layer and a surface oxide layer from a substrate surface by the sonocapillary effect based on a cavitation phenomenon, so that the intimate contact is achieved at the beginning of hot-dip coating. The application of ultrasonic vibration to hot-dipping is effective to control a reaction layer with less than 5μm in thickness. An impact test exhibits that the good adhesive strength is approved in hot-dipped aluminum coatings with a thin reaction layer of approximately 5μm.

  15. Conversion of hot coke oven gas into light fuel gas over Ni/Al{sub 2}O{sub 3} catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Li, L.Y.; Morishita, K.; Takarada, T. [Gunma University, Gunma (Japan). Dept. of Biology & Chemical Engineering

    2006-04-15

    Conversion of hot coke oven gas (COG, containing tarry material) into light fuel gas over a Ni/Al{sub 2}O{sub 3} catalyst was studied. Laboratory scale tests were carried out in a two-stage fixed-bed reactor at ambient pressure. The nickel catalyst promoted the hydropyrolysis reaction of tarry materials. High yields of total product gas and methane were obtained at high hydrogen concentrations. If the hydrogen supply was adequate for hydropyrolysis of the tarry material, conversion of coal volatiles was high, at more than 95% on carbon balance, even with a gas residence time as short as 0.15 s in the catalyst bed. The product gas yield depended on catalytic temperature. At 923 K, the maximum conversion of coal volatiles into the light gas was achieved at 95.0% on carbon balance, with methane 86.7 vol% of the carbonaceous gas product. Although carbon deposits deactivated the catalyst after a long period of use, the catalyst could be regenerated by treatment with oxygen at 800 K, providing high activity in subsequent decomposition of tarry material. The influence of sulphide on the tarry material decomposition reaction was small even in a 2000 ppm H{sub 2}S atmosphere.

  16. DYNAMIC S0 GALAXIES. II. THE ROLE OF DIFFUSE HOT GAS

    International Nuclear Information System (INIS)

    Li Jiangtao; Chen Yang; Daniel Wang, Q.; Li Zhiyuan

    2011-01-01

    Cold gas loss is thought to be important in star formation quenching and morphological transition during the evolution of S0 galaxies. In high-density environments, this gas loss can be achieved via many external mechanisms. However, in relatively isolated environments, where these external mechanisms cannot be efficient, the gas loss must then be dominated by some internal processes. We have performed Chandra analysis of hot gas in five nearby isolated S0 galaxies, based on the quantitative subtraction of various stellar contributions. We find that all the galaxies studied in the present work are X-ray faint, with the luminosity of the hot gas (L X ) typically accounting for ∼ X at the low-mass end (typically with K-band luminosity L K ∼ 11 L sun,K ). However, at the high-mass end, S0 galaxies tend to have significantly lower L X than elliptical galaxies of the same stellar masses, as already shown in previous observational and theoretical works. We further discuss the potential relationship of the diffuse X-ray emission with the cold (atomic and molecular) gas content in the S0 and elliptical galaxies included in our study. We find that L X /L 2 K tends to correlate positively with the total cold gas mass (M H 2 +H i ) for cold-gas-poor galaxies with M H 2 +H i ∼ 8 M sun , while they anti-correlate with each other for cold-gas-rich galaxies. This cold-hot gas relationship can be explained in a scenario of early-type galaxy evolution, with the leftover cold gas from the precursor star-forming galaxy mainly removed by the long-lasting Type Ia supernova (SN) feedback. The two different trends for cold-gas-rich and cold-gas-poor galaxies may be the results of the initial fast decreasing SN rate and the later fast decreasing mass loading to hot gas, respectively.

  17. Effect of fabric stuff of work clothing on the physiological strain index at hot conditions in the climatic chamber

    Directory of Open Access Journals (Sweden)

    Habibollah Dehghan

    2014-01-01

    Full Text Available Aims: The purpose of the present study was to evaluate the effect of fabric stuff of work clothing that are widely used in Iran industries on the physiological strain index (PSI at hot conditions in the climatic chamber. Materials and Methods: This interventional study was performed upon 18 male students in 16 trials, which included combination of four kinds of work clothing (13.7% viscose (VIS 86.3% polyester(PES, 30.2% cotton [CT]-69.8% PES, 68.5% CT-31.5% PES, 100% CT, two activity levels (light and moderate and two kinds of climatic conditions included hot-wet (T a = 35, RH = 70% and hot-dry (T a = 38, RH = 40%. During each trial, the RH and core temperature was recorded once a minute and then PSI was calculated. Data were analyzed by using SPSS-16 software. Results: The results showed that in hot-wet conditions, the least value of PSI in light and moderate activities was related to 100% CT clothing and 30.2% CT-69.8% PES clothing, respectively. In hot-dry conditions, the least value of PSI in both of activities was related to 30.2% CT-69.8% PES clothing. The mean value of PSI in hot-wet conditions, during moderate activity had significant difference for various clothing types (P = 0.044. Conclusion: The research findings showed that for a heat strain reduction in hot-wet conditions at light activity level, 100% CT clothing is suitable. Furthermore, at moderate activity level, 30.2% CT-69.8% PES clothing and in hot-dry conditions, 30.2% CT-69.8% PES is suitable.

  18. The community-level effect of light on germination timing in relation to seed mass: a source of regeneration niche differentiation.

    Science.gov (United States)

    Zhang, Chunhui; Willis, Charles G; Burghardt, Liana T; Qi, Wei; Liu, Kun; Souza-Filho, Paulo Roberto de Moura; Ma, Zhen; Du, Guozhen

    2014-11-01

    Within a community, species may germinate at different times so as to mitigate competition and to take advantage of different aspects of the seasonal environment (temporal niche differentiation). We illustrated a hypothesis of the combined effects of abiotic and biotic competitive factors on germination timing and the subsequent upscale effects on community assembly. We estimated the germination timing (GT) for 476 angiosperm species of the eastern Tibetan Plateau grasslands under two light treatments in the field: high (i.e. natural) light and low light. We also measured the shift in germination timing (SGT) across treatments for all species. Furthermore, we used phylogenetic comparative methods to test if GT and SGT were associated with seed mass, an important factor in competitive interactions. We found a significant positive correlation between GT and seed mass in both light treatments. Additionally, small seeds (early germinating seeds) tended to germinate later and large seeds (late germinating seeds) tended to germinate earlier under low light vs high light conditions. Low light availability can reduce temporal niche differentiation by increasing the overlap in germination time between small and large seeds. In turn, reduced temporal niche differentiation may increase competition in the process of community assembly. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  19. Reactivating Catalytic Surface: Insights into the Role of Hot Holes in Plasmonic Catalysis.

    Science.gov (United States)

    Peng, Tianhuan; Miao, Junjian; Gao, Zhaoshuai; Zhang, Linjuan; Gao, Yi; Fan, Chunhai; Li, Di

    2018-03-01

    Surface plasmon resonance of coinage metal nanoparticles is extensively exploited to promote catalytic reactions via harvesting solar energy. Previous efforts on elucidating the mechanisms of enhanced catalysis are devoted to hot electron-induced photothermal conversion and direct charge transfer to the adsorbed reactants. However, little attention is paid to roles of hot holes that are generated concomitantly with hot electrons. In this work, 13 nm spherical Au nanoparticles with small absorption cross-section are employed to catalyze a well-studied glucose oxidation reaction. Density functional theory calculation and X-ray absorption spectrum analysis reveal that hot holes energetically favor transferring catalytic intermediates to product molecules and then desorbing from the surface of plasmonic catalysts, resulting in the recovery of their catalytic activities. The studies shed new light on the use of the synergy of hot holes and hot electrons for plasmon-promoted catalysis. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Austenite strengthening and softening during hot deformation

    International Nuclear Information System (INIS)

    Tushinskij, L.I.; Vlasov, V.S.; Kazimirova, I.E.; Tokarev, A.O.

    1981-01-01

    Processes of formation of austenite structure of 20 and 12Kh18N10T steels during hot deformation and postdeformation isothermal holdings have been investigated by the methods of analysis of curves of hot deformation, high-temperature metallography and light microscopy. Deformation has been exercised by extention in vacuum with average 4x10 -2 s -1 rate. Deformation temperatures of steel 20 are 930 and 1000 deg C, of steel 12Kh18N10T - 1100 deg C. It is stated that dynamic recrystallization takes place in both investigated steels during hot deformation. In the carbonic steel it is developed by shifting sections of high-angular boundaries, flow stress in this case remains constant. Recrystallization is developed by subgrain coalescence in austenite steel, that brings about preservation of increased defect density in recrystallized volumes. As a result strengthening of steel is continued up to fracture during the increase of the deformation degree. Postdeformation weakening of 12Kh18N10T steel is slowed down as compared with weakening of carbonic steel [ru

  1. Hair treatment process providing dispersed colors by light diffraction

    Science.gov (United States)

    Lamartine, Bruce Carvell; Orler, E. Bruce; Sutton, Richard Matthew Charles; Song, Shuangqi

    2013-12-17

    Hair was coated with polymer-containing fluid and then hot pressed to form a composite of hair and a polymer film imprinted with a nanopattern. Polychromatic light incident on the nanopattern is diffracted into dispersed colored light.

  2. Book Review of - The lightness of being: mass, ether, and unification of the forces

    International Nuclear Information System (INIS)

    Kronfeld, Andreas S.

    2009-01-01

    How can an electron be both a wave and a particle? At the same time? Because it is a quantum field. That key insight seems to be underappreciated, given the awe and mysticism that permeate most nontechnical discussions of modern physics. Perhaps the root of the problem is that most popularizations of quantum mechanics and of particle physics shy away from quantized fields, the natural language for microscopic phenomena. In 'The Lightness of Being: Mass, Ether, and the Unification of Forces', Frank Wilczek confronts quantum field theory head on, demystifying not only wave-particle duality but also the origin of mass for hadrons (that is, everyday matter). Wilczek is the Herman Feshbach Professor of Physics at MIT and a co-recipient of the 2004 Nobel Prize in Physics. His research has spanned almost all aspects of theoretical particle physics, with significant forays into condensed-matter physics and dense nuclear matter (condensed quark matter, one might say). Recurring themes are the richness of quantum chromodynamics (QCD) and the alluring ideas of unification. His breadth and depth make him a sought after speaker for colloquia and public lectures. Wilczek also contributes an occasional Reference Frame column to 'Physics Today'. The material in 'The Lightness of Being' reflects the scope of the author's research. The book consists of three parts: the quantum fields of QCD (the ether that makes mass), gravitation (the ether that feels mass), and unification. Part 1, which traces notions of mass from Isaac Newton's time through theoretical and computational results of the past 40 years, is the most substantial and original; it is rich, modern, and rooted in observed phenomena. Part 2 continues in the same vein as it connects gravity, also an observed phenomenon, to QCD. Part 3 is more conventional, for a popularization of particle physics, in its focus on speculative ideas that (still) await direct experimental tests. Readers of 'Physics Today' will know that

  3. [Rapid screening the alkaloids of poppy shell in hot pot condiment, beef noodle soup and seasoning by direct analysis in real time-tandem mass spectrometry].

    Science.gov (United States)

    Zhang, Baile; Gao, Lihong; Xie, Yingshuang; Zhou, Wei; Chen, Xiaofeng; Lei, Chunni; Zhang, Huan

    2017-07-08

    A direct analysis in real time tandem mass spectrometry (DART-MS/MS) method was established for quickly screening five illegally added alkaloids of poppy shell from the hot pot condiment, beef noodle soup and seasoning. The samples were extracted and purified by acetonitrile, and then injected under the conditions of ionization temperature of 300℃, grid electrode voltage of 150 V and sampling rate of 0.8 mm/s using DART in the positive ion mode. The determination was conducted by tandem mass spectrometry in positive ESI mode under multiple reaction monitoring (MRM) mode. The method is simple and rapid, and can meet the requirement of rapid screening and analysis of large quantities of samples.

  4. Vector manifestation and violation of vector dominance in hot matter

    International Nuclear Information System (INIS)

    Harada, Masayasu; Sasaki, Chihiro

    2004-01-01

    We show the details of the calculation of the hadronic thermal corrections to the two-point functions in the effective field theory of QCD for pions and vector mesons based on the hidden local symmetry (HLS) in hot matter using the background field gauge. We study the temperature dependence of the pion velocity in the low-temperature region determined from the hadronic thermal corrections, and show that, due to the presence of the dynamical vector meson, the pion velocity is smaller than the speed of the light already at one-loop level, in contrast to the result obtained in the ordinary chiral perturbation theory including only the pion at one-loop. Including the intrinsic temperature dependences of the parameters of the HLS Lagrangian determined from the underlying QCD through the Wilsonian matching, we show how the vector manifestation (VM), in which the massless vector meson becomes the chiral partner of pion, is realized at the critical temperature. We present a new prediction of the VM on the direct photon-π-π coupling which measures the validity of the vector dominance (VD) of the electromagnetic form factor of the pion: we find that the VD is largely violated at the critical temperature, which indicates that the assumption of the VD made in several analyses on the dilepton spectra in hot matter may need to be weakened for consistently including the effect of the dropping mass of the vector meson

  5. THE FREQUENCY OF HOT JUPITERS IN THE GALAXY: RESULTS FROM THE SuperLupus SURVEY

    International Nuclear Information System (INIS)

    Bayliss, Daniel D. R.; Sackett, Penny D.

    2011-01-01

    We present the results of the SuperLupus Survey for transiting hot Jupiter planets, which monitored a single Galactic disk field spanning 0.66 deg 2 for 108 nights over three years. Ten candidates were detected: one is a transiting planet, two remain candidates, and seven have been subsequently identified as false positives. We construct a new image quality metric, S j , based on the behavior of 26,859 light curves, which allows us to discard poor images in an objective and quantitative manner. Furthermore, in some cases we are able to identify statistical false positives by analyzing temporal correlations between S j and transit signatures. We use Monte Carlo simulations to measure our detection efficiency by injecting artificial transits onto real light curves and applying identical selection criteria as used in our survey. We find at 90% confidence level that 0.10 +0.27 –0.08 % of dwarf stars host a hot Jupiter with a period of 1-10 days. Our results are consistent with other transit surveys, but appear consistently lower than the hot Jupiter frequencies reported from radial velocity surveys, a difference we attribute, at least in part, to the difference in stellar populations probed. In light of our determination of the frequency of hot Jupiters in Galactic field stars, previous null results for transiting planets in open cluster and globular cluster surveys no longer appear anomalously low.

  6. An automated decision-tree approach to predicting protein interaction hot spots.

    Science.gov (United States)

    Darnell, Steven J; Page, David; Mitchell, Julie C

    2007-09-01

    Protein-protein interactions can be altered by mutating one or more "hot spots," the subset of residues that account for most of the interface's binding free energy. The identification of hot spots requires a significant experimental effort, highlighting the practical value of hot spot predictions. We present two knowledge-based models that improve the ability to predict hot spots: K-FADE uses shape specificity features calculated by the Fast Atomic Density Evaluation (FADE) program, and K-CON uses biochemical contact features. The combined K-FADE/CON (KFC) model displays better overall predictive accuracy than computational alanine scanning (Robetta-Ala). In addition, because these methods predict different subsets of known hot spots, a large and significant increase in accuracy is achieved by combining KFC and Robetta-Ala. The KFC analysis is applied to the calmodulin (CaM)/smooth muscle myosin light chain kinase (smMLCK) interface, and to the bone morphogenetic protein-2 (BMP-2)/BMP receptor-type I (BMPR-IA) interface. The results indicate a strong correlation between KFC hot spot predictions and mutations that significantly reduce the binding affinity of the interface. 2007 Wiley-Liss, Inc.

  7. Mass shifts of charmoniums and electromagnetic signals

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, T.; Miyamura, O.; Hirose, K.; Kanki, T.

    1988-04-01

    Mass of psi' below deconfining transition is discussed. It is sensitive to change of string tension. Observations of masses of charmoniums in hot fire ball by electromagnetic probes are considered.

  8. Mixing Hot and Cold Water Streams at a T-Junction

    Science.gov (United States)

    Sharp, David; Zhang, Mingqian; Xu, Zhenghe; Ryan, Jim; Wanke, Sieghard; Afacan, Artin

    2008-01-01

    A simple mixing of a hot- and cold-water stream at a T-junction was investigated. The main objective was to use mass and energy balance equations to predict mass low rates and the temperature of the mixed stream after the T-junction, and then compare these with the measured values. Furthermore, the thermocouple location after the T-junction and…

  9. Alpha-Gamma Hot-Cell Facility at Argonne National Laboratory East

    International Nuclear Information System (INIS)

    Neimark, L.A.; Jackson, W.D.; Donahue, D.A.

    1979-01-01

    The Alpha-Gamma Hot-Cell Facility has been in operation at Argonne National Laboratory East (ANL-E) for 15 years. The facility was designed for plutonium research in support of ANL's LMFBR program. The facility consists of a kilocurie, nitrogen-atmosphere alpha-gamma hot cell and supporting laboratories. Modifications to the facility and its equipment have been made over the years as the workload and nature of the work changed. These modifications included inerting the entire hot cell, adding four work stations, modifying in-loading procedures and examination equipment to handle longer test articles, and changing to a new sodium-vapor lighting system. Future upgrading includes the addition of a decontamination and repair facility, use of radio-controlled transfer carts, refurbishment of the zinc bromide windows, and the installation of an Auger microprobe

  10. Hot nuclei studies with a 4 π-Neutron detector

    International Nuclear Information System (INIS)

    Galin, J.; Crema, E.; Doubre, H.; Guerreau, D.; Jiang, D.X.; Morjean, M.; Piasecki, E.; Pouthas, J.; Saint-Laurent, F.; Sokolov, A.; Wang, X.D.; Charvet, J.L.; Frehaut, J.; Lott, B.; Magnago, C.; Patin, Y.; Gatty, B.; Jacquet, D.; Lott, B.

    1989-01-01

    When studying the behavior of hot nuclei, the challenge is twofold: how are they formed in nucleus-nucleus collisions and how do they decay Systematic studies have been undertaken at GANIL by bombarding heavy targets (Au, Th) with intermediate energy projectiles (27, 35, 44 and 77 MeV/u Ar and 32 MeV/u Kr). For such neutron rich systems the thermalized energy can be roughly evaluated simply by measuring the multiplicity of evaporated neutrons using a 4 π Gd loaded, liquid scintillator detector. The influence of the bombarding energy and projectile mass on the energy dissipation has been investigated for different exit channels and special emphasis has been put in the study of the most dissipative collisions. The thermal energy, derived by summing the energy removed by both evaporated neutrons and light charged particles is shown to saturate at E * ≅ 650 MeV in the Ar induced reactions between 27 and 77 MeV/u, in good consistency with the predictions of semi-classical Landau-Vlasov calculations

  11. Hot-wire air flow meter for gasoline fuel-injection system. Calculation of air mass in cylinder during transient condition; Gasoline funsha system yo no netsusenshiki kuki ryuryokei. Kato untenji no cylinder juten kukiryo no keisan

    Energy Technology Data Exchange (ETDEWEB)

    Oyama, Y [Hitachi Car Engineering, Ltd., Tokyo (Japan); Nishimura, Y; Osuga, M; Yamauchi, T [Hitachi, Ltd., Tokyo (Japan)

    1997-10-01

    Air flow characteristics of hot-wire air flow meters for gasoline fuel-injection systems with supercharging and exhaust gas recycle during transient conditions were investigated to analyze a simple method for calculating air mass in cylinder. It was clarified that the air mass in cylinder could be calculated by compensating for the change of air mass in intake system by using aerodynamic models of intake system. 3 refs., 6 figs., 1 tab.

  12. HOT 2012

    DEFF Research Database (Denmark)

    Lund, Henriette Romme

    Undersøgelse af, hvad der er hot - og hvad der burde være hot på læseområdet med 21 læsekyndige. Undersøgelsen er gennemført siden 2010. HOT-undersøgelsen er foretaget af Nationalt Videncenter for Læsning - Professionshøjskolerne i samarb. med Dansklærerforeningen......Undersøgelse af, hvad der er hot - og hvad der burde være hot på læseområdet med 21 læsekyndige. Undersøgelsen er gennemført siden 2010. HOT-undersøgelsen er foretaget af Nationalt Videncenter for Læsning - Professionshøjskolerne i samarb. med Dansklærerforeningen...

  13. Models of light singlet fermion and neutrino phenomenology

    International Nuclear Information System (INIS)

    Chun, E.J.; Joshipura, A.S.; Smirnov, A.Yu.

    1995-05-01

    We suggest that a single fermion S exists beyond the standard see-saw structure. It mixes with light neutrinos via interactions with the right-handed neutrino components, so that ν e → S conversion solves the solar neutrino problem. Supersymmetry endowed with R-symmetry is shown to give a natural framework for existence, mass scale (∼ 3 · 10 -3 eV) and mixing (sin 2 2θ es ∼ (0.1 - 1.5) · 10 -2 ) of such a fermion. Models with an approximate horizontal symmetry are constructed, which embed the fermion S and explain simultaneously solar, atmospheric, hot dark matter problems as well as may predict the oscillation ν-bar μ → ν-bar e in the region of sensitivity of KARMEN and LSND experiments. (author). 24 refs

  14. Interpretation of eclipsing light curves of dwarf novae

    International Nuclear Information System (INIS)

    Matvienko, A.N.; Cherepashchuk, A.M.; Yagola, A.G.

    1988-01-01

    The method for interpretation of eclipsing light curves of dwarf novae is proposed, taking into account the influence of the hot spot situated in the outer part of the disk-like envelope surrounding a white dwarf. This method is applied to the analysis of the eclipsing light curves of the system Z Cha in the quiet and active stages. It is shown that the optical luminosity of the hot spot in the system Z Cha in the active stage is 3-5 times greater than that in the quiet stage. Radius of the disk-like envelope in the active stage is more than twice greater than that in the quiet stage

  15. Cardiac autonomic function and hot flashes among perimenopausal and postmenopausal women.

    Science.gov (United States)

    Gibson, Carolyn J; Mendes, Wendy Berry; Schembri, Michael; Grady, Deborah; Huang, Alison J

    2017-07-01

    Abnormalities in autonomic function are posited to play a pathophysiologic role in menopausal hot flashes. We examined relationships between resting cardiac autonomic activity and hot flashes in perimenopausal and postmenopausal women. Autonomic function was assessed at baseline and 12 weeks among perimenopausal and postmenopausal women (n = 121, mean age 53 years) in a randomized trial of slow-paced respiration for hot flashes. Pre-ejection period (PEP), a marker of sympathetic activation, was measured with impedance cardiography. Respiratory sinus arrhythmia (RSA), a marker of parasympathetic activation, was measured with electrocardiography. Participants self-reported hot flash frequency and severity in 7-day symptom diaries. Analysis of covariance models were used to relate autonomic function and hot flash frequency and severity at baseline, and to relate changes in autonomic function to changes in hot flash frequency and severity over 12 weeks, adjusting for age, body mass index, and intervention assignment. PEP was not associated with hot flash frequency or severity at baseline or over 12 weeks (P > 0.05 for all). In contrast, there was a trend toward greater frequency of moderate-to-severe hot flashes with higher RSA at baseline (β = 0.43, P = 0.06), and a positive association between change in RSA and change in frequency of moderate-to-severe hot flashes over 12 weeks (β = 0.63, P = 0.04). Among perimenopausal and postmenopausal women with hot flashes, variations in hot flash frequency and severity were not explained by variations in resting sympathetic activation. Greater parasympathetic activation was associated with more frequent moderate-to-severe hot flashes, which may reflect increased sensitivity to perceiving hot flashes.

  16. Extracting the temperature of hot carriers in time- and angle-resolved photoemission

    DEFF Research Database (Denmark)

    Ulstrup, Søren; Johannsen, Jens Christian; Grioni, Marco

    2014-01-01

    The interaction of light with a material’s electronic system creates an out-of-equilibrium (nonthermal) distribution of optically excited electrons. Non-equilibrium dynamics relaxes this distribution on an ultrafast timescale to a hot Fermi-Dirac distribution with a well-defined temperature......, we introduce a method that circumvents these difficulties and accurately extracts both the temperature and the position of the Fermi level for a hot carrier distribution by tracking the occupation statistics of the carriers measured in a TR-ARPES experiment...

  17. Composition of hot ions /0.1-16 keV/e/ as observed by the GEOS and ISEE mass spectrometers and inferences for the origin and circulation of magnetospheric plasmas

    Science.gov (United States)

    Balsiger, H.

    1981-01-01

    The composition of hot magnetospheric plasma through different regions of the magnetosphere is described on the basis of mass spectrometer measurements by the GEOS 1, GEOS 2, and ISEE-1 spacecraft. Coordinated composition measurements on the different spacecraft also provide information on the spatial and temporal characteristics of the plasma during storms. Data on ion origins are also provided.

  18. Formation and early evolution of galaxies: Constraints on the properties of hot protogalaxies

    International Nuclear Information System (INIS)

    Berman, V.G.; Suchkov, A.A.

    1989-01-01

    In the framework of the hot model of galaxy formation, the following results are obtained: (1) to explain the mass and chemical composition of the intergalactic medium, the mass of the stellar component, and the mass of the x-ray coronas of giant elliptical and spiral galaxies (M s ∼ 10 11 Mass Sun ) the protogalaxies must have been heated to temperatures approximately five times greater than the virial temperature; (2) the x-ray luminosities of the coronas of models of spiral galaxies are less than for the analogous models of elliptical galaxies. Moreover, for unit potential of hidden mass the stellar mass of spiral galaxies is an order of magnitude greater; (3) if a hot protogalaxy is initially compact (R ∼ 20 kpc), then the stellar component is formed rapidly, during a time t ∼ 1 x 10 9 yr; but if the protogalaxy is diffuse (R ∼ 100 kpc), then t ∼ (5-7) x 10 9 yr; (4) coronas are not formed in models of heat-conducting protogalaxies; (5) hidden mass cannot be formed by low-mass stars formed in cooling flows - such flows do not arise if hidden mass is not present from the beginning. 23 refs., 4 figs., 2 tabs

  19. Meson exchange second class currents and the neutrino mass in the muon capture by light nuclei

    International Nuclear Information System (INIS)

    Katkhat, Ch.L.

    1988-01-01

    Influence of the Kubodera-Delorme-Rho model parameters (ζ and ξ), the scalar form factor (F s ) and the muonic neutrino rest mass (m νμ ) on the asymmetry coefficient (α μν ) of neutrino emission with respect to the muon spin orientation in the muon capture by light nuclei is analyzed. It is shown, that the mass m νμ , the parameters of ζ and ξ, and the form factor F s may be estimated by studying the coefficient α μν in O -> O, Gamov-Teller, and mixed transitions, respectively

  20. Weighing the Dark and Light in Cosmology with Machine Learning

    Science.gov (United States)

    Trac, Hy

    2017-09-01

    Galaxy clusters contain large amounts of cold dark matter, hot ionized gas, and tens to hundreds of visible galaxies. They are the largest gravitationally bound systems in the Universe and make excellent laboratories for studying cosmology and astrophysics. Historically, Fritz Zwicky postulated the existence of dark matter when he inferred the total mass of the nearby Coma Cluster from the motions of its galaxies and found it to be much larger than the visible mass. Nowadays, the abundance of clusters as a function of mass and time can be used to study structure formation and constrain cosmological parameters. Dynamical measurements of the motions of galaxies can be used to probe the entire mass distribution, but standard analyses yield unwanted high mass errors. First, we show that modern machine learning algorithms can improve mass measurements by more than a factor of two compared to using standard scaling relations. Support Distribution Machines are used to train and test on the entire distribution of galaxy velocities to maximally use available information. Second, we discuss how Deep Learning can be used to train on multi-wavelength images of galaxies and clusters and to predict the underlying total matter distribution. By applying machine learning to observations and simulations, we can map out the dark and light in the Universe. DOE DE-SC0011114, NSF RI-1563887.

  1. Reduction in biomass burning aerosol light absorption upon humidification: roles of inorganically-induced hygroscopicity, particle collapse, and photoacoustic heat and mass transfer

    Science.gov (United States)

    Lewis, K. A.; Arnott, W. P.; Moosmüller, H.; Chakrabarty, R. K.; Carrico, C. M.; Kreidenweis, S. M.; Day, D. E.; Malm, W. C.; Laskin, A.; Jimenez, J. L.; Ulbrich, I. M.; Huffman, J. A.; Onasch, T. B.; Trimborn, A.; Liu, L.; Mishchenko, M. I.

    2009-11-01

    Smoke particle emissions from the combustion of biomass fuels typical for the western and southeastern United States were studied and compared under high humidity and ambient conditions in the laboratory. The fuels used were Montana ponderosa pine (Pinus ponderosa), southern California chamise (Adenostoma fasciculatum), and Florida saw palmetto (Serenoa repens). Information on the non-refractory chemical composition of biomass burning aerosol from each fuel was obtained with an aerosol mass spectrometer and through estimation of the black carbon concentration from light absorption measurements at 870 nm. Changes in the optical and physical particle properties under high humidity conditions were observed for hygroscopic smoke particles containing substantial inorganic mass fractions that were emitted from combustion of chamise and palmetto fuels. Light scattering cross sections increased under high humidity for these particles, consistent with the hygroscopic growth measured for 100 nm particles in HTDMA measurements. Photoacoustic measurements of aerosol light absorption coefficients revealed a 20% reduction with increasing relative humidity, contrary to the expectation of light absorption enhancement by the liquid coating taken up by hygroscopic particles. This reduction is hypothesized to arise from two mechanisms: (1) shielding of inner monomers after particle consolidation or collapse with water uptake; (2) the lower case contribution of mass transfer through evaporation and condensation at high relative humidity (RH) to the usual heat transfer pathway for energy release by laser-heated particles in the photoacoustic measurement of aerosol light absorption. The mass transfer contribution is used to evaluate the fraction of aerosol surface covered with liquid water solution as a function of RH.

  2. Reduction in biomass burning aerosol light absorption upon humidification: Roles of inorganically-induced hygroscopicity, particle collapse, and photoacoustic heat and mass transfer

    Energy Technology Data Exchange (ETDEWEB)

    lewis, Kristen A.; Arnott, W. P.; Moosmuller, H.; Chakrabarti, Raj; Carrico, Christian M.; Kreidenweis, Sonia M.; Day, Derek E.; Malm, William C.; Laskin, Alexander; Jimenez, Jose L.; Ulbrich, Ingrid M.; Huffman, John A.; Onasch, Timothy B.; Trimborn, Achim; Liu, Li; Mishchenko, M.

    2009-11-27

    Smoke particle emissions from the combustion of biomass fuels typical for the western and southeastern United States were studied and compared under high humidity and ambient conditions in the laboratory. The fuels used are Montana ponderosa pine (Pinus ponderosa), southern California chamise (Adenostoma fasciculatum), and Florida saw palmetto (Serenoa repens). Information on the non-refractory chemical composition of biomass burning aerosol from each fuel was obtained with an aerosol mass spectrometer and through estimation of the black carbon concentration from light absorption measurements at 870 nm. Changes in the optical and physical particle properties under high humidity conditions were observed for hygroscopic smoke particles containing substantial inorganic mass fractions that were emitted from combustion of chamise and palmetto fuels. Light scattering cross sections increased under high humidity for these particles, consistent with the hygroscopic growth measured for 100 nm particles in HTDMA measurements. Photoacoustic measurements of aerosol light absorption coefficients reveal a 20% reduction with increasing relative humidity, contrary to the expectation of light absorption enhancement by the liquid coating taken up by hygroscopic particles. This reduction is hypothesized to arise from two mechanisms: 1. Shielding of inner monomers after particle consolidation or collapse with water uptake; 2. The contribution of mass transfer through evaporation and condensation at high relative humidity to the usual heat transfer pathway for energy release by laser heated particles in the photoacoustic measurement of aerosol light absorption. The mass transfer contribution is used to evaluate the fraction of aerosol surface covered with liquid water solution as a function of RH.

  3. BLACK HOLE-NEUTRON STAR MERGERS WITH A HOT NUCLEAR EQUATION OF STATE: OUTFLOW AND NEUTRINO-COOLED DISK FOR A LOW-MASS, HIGH-SPIN CASE

    International Nuclear Information System (INIS)

    Deaton, M. Brett; Duez, Matthew D.; Foucart, Francois; O'Connor, Evan; Ott, Christian D.; Scheel, Mark A.; Szilagyi, Bela; Kidder, Lawrence E.; Muhlberger, Curran D.

    2013-01-01

    Neutrino emission significantly affects the evolution of the accretion tori formed in black hole-neutron star mergers. It removes energy from the disk, alters its composition, and provides a potential power source for a gamma-ray burst. To study these effects, simulations in general relativity with a hot microphysical equation of state (EOS) and neutrino feedback are needed. We present the first such simulation, using a neutrino leakage scheme for cooling to capture the most essential effects and considering a moderate mass (1.4 M ☉ neutron star, 5.6 M ☉ black hole), high-spin (black hole J/M 2 = 0.9) system with the K 0 = 220 MeV Lattimer-Swesty EOS. We find that about 0.08 M ☉ of nuclear matter is ejected from the system, while another 0.3 M ☉ forms a hot, compact accretion disk. The primary effects of the escaping neutrinos are (1) to make the disk much denser and more compact, (2) to cause the average electron fraction Y e of the disk to rise to about 0.2 and then gradually decrease again, and (3) to gradually cool the disk. The disk is initially hot (T ∼ 6 MeV) and luminous in neutrinos (L ν ∼ 10 54 erg s –1 ), but the neutrino luminosity decreases by an order of magnitude over 50 ms of post-merger evolution

  4. Properties of hot luminous stars; Proceedings of the First Boulder-Munich Workshop, Boulder, CO, Aug. 6-11, 1988

    International Nuclear Information System (INIS)

    Garmany, C.D.

    1990-01-01

    Various papers on the properties of hot luminous stars are presented. Individual topics addressed include: problems in photometry of early-type stars; digital optical morphology of OB spectra; massive-star content of the Magellanic Clouds; observations of massive OB stars; LSS 3074, a new double-lined early O-type binary; non-LTE line blanketing with elements 1-28; non-LTE analysis of four PG1159 stars; rescaling method for model atmospheres of hot stars; stellar wind albedo effects on hot photospheres; atomic data and models for hot star abundance determinations; ring nebulae analysis as a probe for WR atmospheres; coordinated observations of P Cygni; radiation-driven winds of hot luminous stars; winds of O stars: velocities and ionization; methods of radiative transfer in expanding atmospheres; mass loss from extragalactic O stars; H-alpha observations of O- and B-type stars; applicability of steady models for hot-star winds; mass of the O6Iaf star HD 153919; stellar winds in Beta Lyrae; models of WR stars; observational abundances of WR stars, the all-variable WC7 binary HD193793

  5. Hair treatment device for providing dispersed colors by light diffraction

    Science.gov (United States)

    Lamartine, Bruce Carvell; Orler, Bruce E.; Sutton, Richard Matthew Charles; Song, Shuangqi

    2016-01-26

    Hair was coated with polymer-containing fluid and then hot pressed to form a composite of hair and a polymer film imprinted with a nanopattern. Polychromatic light incident on the nanopattern is diffracted into dispersed colored light.

  6. EVENT DETECTION USING MOBILE PHONE MASS GPS DATA AND THEIR RELIAVILITY VERIFICATION BY DMSP/OLS NIGHT LIGHT IMAGE

    Directory of Open Access Journals (Sweden)

    A. Yuki

    2016-06-01

    Full Text Available In this study, we developed a method to detect sudden population concentration on a certain day and area, that is, an “Event,” all over Japan in 2012 using mass GPS data provided from mobile phone users. First, stay locations of all phone users were detected using existing methods. Second, areas and days where Events occurred were detected by aggregation of mass stay locations into 1-km-square grid polygons. Finally, the proposed method could detect Events with an especially large number of visitors in the year by removing the influences of Events that occurred continuously throughout the year. In addition, we demonstrated reasonable reliability of the proposed Event detection method by comparing the results of Event detection with light intensities obtained from the night light images from the DMSP/OLS night light images. Our method can detect not only positive events such as festivals but also negative events such as natural disasters and road accidents. These results are expected to support policy development of urban planning, disaster prevention, and transportation management.

  7. Baryon Budget of the Hot Circumgalactic Medium of Massive Spiral Galaxies

    Science.gov (United States)

    Li, Jiang-Tao; Bregman, Joel N.; Wang, Q. Daniel; Crain, Robert A.; Anderson, Michael E.

    2018-03-01

    The baryon content around local galaxies is observed to be much less than is needed in Big Bang nucleosynthesis. Simulations indicate that a significant fraction of these “missing baryons” may be stored in a hot tenuous circumgalactic medium (CGM) around massive galaxies extending to or even beyond the virial radius of their dark matter halos. Previous observations in X-ray and Sunyaev–Zel’dovich (SZ) signals claimed that ∼(1–50)% of the expected baryons are stored in a hot CGM within the virial radius. The large scatter is mainly caused by the very uncertain extrapolation of the hot gas density profile based on the detection in a small radial range (typically within 10%–20% of the virial radius). Here, we report stacking X-ray observations of six local isolated massive spiral galaxies from the CGM-MASS sample. We find that the mean density profile can be characterized by a single power law out to a galactocentric radius of ≈200 kpc (or ≈130 kpc above the 1σ background uncertainty), about half the virial radius of the dark matter halo. We can now estimate that the hot CGM within the virial radius accounts for (8 ± 4)% of the baryonic mass expected for the halos. Including the stars, the baryon fraction is (27 ± 16)%, or (39 ± 20)% by assuming a flattened density profile at r ≳ 130 kpc. We conclude that the hot baryons within the virial radius of massive galaxy halos are insufficient to explain the “missing baryons.”

  8. Manufacturing and mechanical property test of the large-scale oxide dispersion strengthened martensitic mother tube by hot isostatic pressing and hot extrusion process

    International Nuclear Information System (INIS)

    Narita, Takeshi; Ukai, Shigeharu; Kaito, Takeji; Ohtsuka, Satoshi; Fujiwara, Masayuki

    2003-09-01

    Mass production capability of Oxide Dispersion Strengthened (ODS) ferritic steel cladding (9Cr) is evaluated in the Phase II of the Feasibility Studies on Commercialized Fast Reactor Cycle System. The cost for manufacturing mother tube is a dominant factor in the total cost for manufacturing ODS ferritic cladding. In this study, the large-scale 9Cr-ODS martensitic mother tube was produced by overseas supplier with mass production equipments for commercialized ODS steels. The process of manufacturing the ODS mother tube consists of raw material powder production, mechanical alloying by high energy ball mill, hot isostatic pressing(HIP), and hot extrusion. Following results were obtained in this study. (1) Micro structure of the ODS steels is equivalent to that of domestic products, and fine oxides are uniformly distributed. The mechanical alloying by large capacity (1 ton) ball mill can be satisfactorily carried out. (2) A large scale mother tube (65 mm OD x 48 mm ID x 10,000 mm L), which can produce about 60 pieces of 3 m length ODS ferritic claddings by four times cold rolling, have been successfully manufactured through HIP and Hot Extrusion process. (3) Rough surface of the mother tubes produced in this study can be improved by selecting the reasonable hot extrusion condition. (4) Hardness and tensile strength of the manufactured ODS steels are lower than domestic products with same chemical composition. This is owing to the high aluminum content in the product, and those properties could be improved by decreasing the aluminum content in the raw material powder. (author)

  9. Alternative hot spot formation techniques using liquid deuterium-tritium layer inertial confinement fusion capsules

    International Nuclear Information System (INIS)

    Olson, R. E.; Leeper, R. J.

    2013-01-01

    The baseline DT ice layer inertial confinement fusion (ICF) ignition capsule design requires a hot spot convergence ratio of ∼34 with a hot spot that is formed from DT mass originally residing in a very thin layer at the inner DT ice surface. In the present paper, we propose alternative ICF capsule designs in which the hot spot is formed mostly or entirely from mass originating within a spherical volume of DT vapor. Simulations of the implosion and hot spot formation in two DT liquid layer ICF capsule concepts—the DT wetted hydrocarbon (CH) foam concept and the “fast formed liquid” (FFL) concept—are described and compared to simulations of standard DT ice layer capsules. 1D simulations are used to compare the drive requirements, the optimal shock timing, the radial dependence of hot spot specific energy gain, and the hot spot convergence ratio in low vapor pressure (DT ice) and high vapor pressure (DT liquid) capsules. 2D simulations are used to compare the relative sensitivities to low-mode x-ray flux asymmetries in the DT ice and DT liquid capsules. It is found that the overall thermonuclear yields predicted for DT liquid layer capsules are less than yields predicted for DT ice layer capsules in simulations using comparable capsule size and absorbed energy. However, the wetted foam and FFL designs allow for flexibility in hot spot convergence ratio through the adjustment of the initial cryogenic capsule temperature and, hence, DT vapor density, with a potentially improved robustness to low-mode x-ray flux asymmetry

  10. Hot Flashes

    Science.gov (United States)

    Hot flashes Overview Hot flashes are sudden feelings of warmth, which are usually most intense over the face, neck and chest. Your skin might redden, as if you're blushing. Hot flashes can also cause sweating, and if you ...

  11. PWR hot leg natural circulation modeling with MELCOR code

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Hong; Lee, Jong In [Korea Institute of Nuclear Safety, Taejon (Korea, Republic of)

    1998-12-31

    Previous MELCOR and SCDAP/RELAP5 nodalizations for simulating the counter-current, natural circulation behavior of vapor flow within the RCS hot legs and SG U-tubes when core damage progress can not be applied to the steady state and water-filled conditions during the initial period of accident progression because of the artificially high loss coefficients in the hot legs and SG U-tubes which were chosen from results of COMMIX calculation and the Westinghouse natural circulation experiments in a 1/7-scale facility for simulating steam natural circulation behavior in the vessel and circulation modeling which can be used both for the liquid flow condition at steady state and for the vapor flow condition at the later period of in-vessel core damage. For this, the drag forces resulting from the momentum exchange effects between the two vapor streams in the hot leg was modeled as a pressure drop by pump model. This hot leg natural circulation modeling of MELCOR was able to reproduce similar mass flow rates with those predicted by previous models. 6 refs., 2 figs. (Author)

  12. PWR hot leg natural circulation modeling with MELCOR code

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Hong; Lee, Jong In [Korea Institute of Nuclear Safety, Taejon (Korea, Republic of)

    1997-12-31

    Previous MELCOR and SCDAP/RELAP5 nodalizations for simulating the counter-current, natural circulation behavior of vapor flow within the RCS hot legs and SG U-tubes when core damage progress can not be applied to the steady state and water-filled conditions during the initial period of accident progression because of the artificially high loss coefficients in the hot legs and SG U-tubes which were chosen from results of COMMIX calculation and the Westinghouse natural circulation experiments in a 1/7-scale facility for simulating steam natural circulation behavior in the vessel and circulation modeling which can be used both for the liquid flow condition at steady state and for the vapor flow condition at the later period of in-vessel core damage. For this, the drag forces resulting from the momentum exchange effects between the two vapor streams in the hot leg was modeled as a pressure drop by pump model. This hot leg natural circulation modeling of MELCOR was able to reproduce similar mass flow rates with those predicted by previous models. 6 refs., 2 figs. (Author)

  13. Particle-in-cell studies of laser-driven hot spots and a statistical model for mesoscopic properties of Raman backscatter

    International Nuclear Information System (INIS)

    Albright, B.J.; Yin, L.; Bowers, K.J.; Kline, J.L.; Montgomery, D.S.; Fernandez, J.C.; Daughton, W.

    2006-01-01

    The authors use explicit particle-in-cell simulations to model stimulated scattering processes in media with both solitary and multiple laser hot spots. These simulations indicate coupling among hot spots, whereby scattered light, plasma waves, and hot electrons generated in one laser hot spot may propagate to neighboring hot spots, which can be destabilized to enhanced backscatter. A nonlinear statistical model of a stochastic beam exhibiting this coupled behavior is described here. Calibration of the model using particle-in-cell simulations is performed, and a threshold is derived for 'detonation' of the beam to high reflectivity. (authors)

  14. Hot forming of composite prepreg : Experimental study

    Science.gov (United States)

    Tardif, Xavier; Duthille, Bertrand; Bechtel, Stephane; le Pinru, Louis; Campagne, Benjamin; Destombes, Gautier; Deshors, Antoine; Marchand, Christophe; Azzouzi, Khalid El; Moro, Tanguy

    2017-10-01

    The hot forming of thermoset prepreg consists in bending an uncured composite part by applying a mechanical constrain on the hot laminate. Most of the time, the mold is inserted in a vacuum box and the mechanical constrain is applied on the composite laminate by a single membrane or a double-membrane. But the performance improvement products resulted in forming increasingly complex parts with advanced materials having a less formability. These new complex parts require a finer comprehension of the process and an optimization of the key parameters to get acceptable quality. In this work, an experimental study has been carried out to identify the process conditions that do not lead to unacceptable defaults: undulations of fibers. In the present study, downward-bending has been evaluated with an original light mechanical forming concept, for a given stacking sequence. The influence of the part's temperature and the part's bending speed are investigated. To carry this study out, a hot forming test bench has been designed and manufactured to have a precise supervision of the process conditions. It is able to bend parts of 1500 mm length x 600 mm width x 20 mm thick.

  15. Simultaneous mass detection for direct inlet mass spectrometry

    International Nuclear Information System (INIS)

    Gordon, R.L.

    1979-05-01

    The evolution of analytical techniques for application in trace analysis has led to interest in practical methods for real-time monitoring. Direct inlet mass spectrometry (DIMS) has been the subject of considerable activity in recent years. A DIMS instrument is described which consists of an inlet system designed to permit particles entrained in the inlet air stream to strike a hot, oxidized rhenium filament which serves as a surface ionization source. A mass analyzer and detection system then permits identification of the elemental composition of particulates which strike the filament

  16. Pulsational instabilities in hot pre-horizontal branch stars

    Directory of Open Access Journals (Sweden)

    Battich Tiara

    2017-01-01

    Full Text Available The ϵ mechanism is a self-excitation mechanism of pulsations which acts on the regions where nuclear burning takes place. It has been shown that the ϵ mechanism can excite pulsations in models of hot helium-core flash, and that the pulsations of LS IV-14· 116, a He-enriched hot subdwarf star, could be explained that way. We aim to study the ϵmechanism effects on models of hot pre-horizontal branch stars and determine, if possible, a domain of instability in the log g — log Teff plane. We compute non-adiabatic non-radial pulsations on such stellar models, adopting different values of initial chemical abundances and mass of the hydrogen envelope at the time of the main helium flash. We find an instability domain of long-period (400 s ≲ P ≲ 2500 s g-modes for models with 22000K ≲ Teff ≲ 50000K and 4.67 ≲ log g ≲ 6.15.

  17. Estimating the Magnetic Field Strength in Hot Jupiters

    Energy Technology Data Exchange (ETDEWEB)

    Yadav, Rakesh K. [Department of Earth and Planetary Sciences, Harvard University, 20 Oxford Street, Cambridge, MA 02138 (United States); Thorngren, Daniel P., E-mail: rakesh_yadav@fas.harvard.edu [Department of Physics, University of California, Santa Cruz, CA (United States)

    2017-11-01

    A large fraction of known Jupiter-like exoplanets are inflated as compared to Jupiter. These “hot” Jupiters orbit close to their parent star and are bombarded with intense starlight. Many theories have been proposed to explain their radius inflation and several suggest that a small fraction of the incident starlight is injected into the planetary interior, which helps to puff up the planet. How will such energy injection affect the planetary dynamo? In this Letter, we estimate the surface magnetic field strength of hot Jupiters using scaling arguments that relate energy available in planetary interiors to the dynamo-generated magnetic fields. We find that if we take into account the energy injected in the planetary interior that is sufficient to inflate hot Jupiters to observed radii, then the resulting dynamo should be able generate magnetic fields that are more than an order of magnitude stronger than the Jovian values. Our analysis highlights the potential fundamental role of the stellar light in setting the field strength in hot Jupiters.

  18. Advantages of Fast Ignition Scenarios with Two Hot Spots for Space Propulsion Systems

    Science.gov (United States)

    Shmatov, M. L.

    The use of the fast ignition scenarios with the attempts to create two hot spots in one blob of the compressed thermonuclear fuel or, briefly, scenarios with two hot spots in space propulsion systems is proposed. The model, predicting that for such scenarios the probability pf of failure of ignition of thermonuclear microexplosion can be significantly less than that for the similar scenarios with the attempts to create one hot spot in one blob of the compressed fuel, is presented. For space propulsion systems consuming a relatively large amount of propellant, a decrease in pf due to the choice of the scenario with two hot spots can result in large, for example, two-fold, increase in the payload mass. Other advantages of the scenarios with two hot spots and some problems related to them are considered.

  19. Effects of Non-metallic Inclusions on Hot Ductility of High Manganese TWIP Steels Containing Different Aluminum Contents

    Science.gov (United States)

    Wang, Yu-Nan; Yang, Jian; Wang, Rui-Zhi; Xin, Xiu-Ling; Xu, Long-Yun

    2016-06-01

    The characteristics of inclusions in Fe-16Mn- xAl-0.6C ( x = 0.002, 0.033, 0.54, 2.10 mass pct) steels have been investigated and their effects on hot ductility of the high manganese TWIP steels have been discussed. Ductility is very poor in the steel containing 0.54 mass pct aluminum, which is lower than 20 pct in the temperature range of 873 K to 1473 K (600 °C to 1200 °C). For the steels containing 0.002 and 2.10 mass pct aluminum, ductility is higher than 40 pct in the same temperature range. The hot ductility of steel containing 0.033 mass pct aluminum is higher than 30 pct throughout the temperature range under examination. With increasing aluminum content, the main inclusions in the steels change along the route of MnO/(MnO + MnS) → MnS/(Al2O3 + MnS) → AlN/(Al2O3 + MnS)/(MgAl2O4 + MnS) → AlN. The thermodynamic results of inclusion types calculated with FactSage software are in agreement with the experimental observation results. The inclusions in the steels containing 0.002 mass pct aluminum do not deteriorate the hot ductility. MnS inclusions whose average size, number density, and volume ratio are 1.12 μm, 15.62 mm-2, and 2.51 × 10-6 in the steel containing 0.033 mass pct aluminum reduce the ductility. In the steel containing 0.54 mass pct aluminum, AlN inclusions whose average size, number density, and volume ratio are 0.878 μm, 16.28 mm-2 and 2.82 × 10-6 can precipitate at the austenite grain boundaries, prevent dynamic recrystallization and deteriorate the hot ductility. On the contrary, in the steel containing 2.10 mass pct aluminum, the average size, number density and volume ratio of AlN inclusions change to 2.418 μm, 35.95 mm-2, and 2.55 × 10-5. They precipitate in the matrix, which do not inhibit dynamic recrystallization and thereby do not lead to poor hot ductility.

  20. Reversible electron–hole separation in a hot carrier solar cell

    International Nuclear Information System (INIS)

    Limpert, S; Bremner, S; Linke, H

    2015-01-01

    Hot-carrier solar cells are envisioned to utilize energy filtering to extract power from photogenerated electron–hole pairs before they thermalize with the lattice, and thus potentially offer higher power conversion efficiency compared to conventional, single absorber solar cells. The efficiency of hot-carrier solar cells can be expected to strongly depend on the details of the energy filtering process, a relationship which to date has not been satisfactorily explored. Here, we establish the conditions under which electron–hole separation in hot-carrier solar cells can occur reversibly, that is, at maximum energy conversion efficiency. We thus focus our analysis on the internal operation of the hot-carrier solar cell itself, and in this work do not consider the photon-mediated coupling to the Sun. After deriving an expression for the voltage of a hot-carrier solar cell valid under conditions of both reversible and irreversible electrical operation, we identify separate contributions to the voltage from the thermoelectric effect and the photovoltaic effect. We find that, under specific conditions, the energy conversion efficiency of a hot-carrier solar cell can exceed the Carnot limit set by the intra-device temperature gradient alone, due to the additional contribution of the quasi-Fermi level splitting in the absorber. We also establish that the open-circuit voltage of a hot-carrier solar cell is not limited by the band gap of the absorber, due to the additional thermoelectric contribution to the voltage. Additionally, we find that a hot-carrier solar cell can be operated in reverse as a thermally driven solid-state light emitter. Our results help explore the fundamental limitations of hot-carrier solar cells, and provide a first step towards providing experimentalists with a guide to the optimal configuration of devices. (paper)

  1. Large-area OLED lightings and their applications

    International Nuclear Information System (INIS)

    Park, J W; Shin, D C; Park, S H

    2011-01-01

    In this paper, we review the key issues related to the fabrication of large-area organic light-emitting devices (OLEDs) for lighting applications. We discuss the origin of a short-circuit problem, luminance non-uniformity, hot spot, efficiency reduction (power loss), and heat generation and present the way of suppressing them. We also introduce three different application areas of large-area OLED lighting panels. They can be integrated with a solar cell for power recycling or inorganic LEDs for emotional lightings. The feasibility of using OLEDs for the application of visible-light communications is also reviewed

  2. Note: a novel vacuum ultraviolet light source assembly with aluminum-coated electrodes for enhancing the ionization efficiency of photoionization mass spectrometry.

    Science.gov (United States)

    Zhu, Zhixiang; Wang, Jian; Qiu, Keqing; Liu, Chengyuan; Qi, Fei; Pan, Yang

    2014-04-01

    A novel vacuum ultraviolet (VUV) light source assembly (VUVLSA) for enhancing the ionization efficiency of photoionization mass spectrometer has been described. The VUVLSA composes of a Krypton lamp and a pair of disk electrodes with circular center cavities. The two interior surfaces that face the photoionization region were aluminum-coated. VUV light can be reflected back and forth in the photoionization region between the electrodes, thus the photoionization efficiency can be greatly enhanced. The performances of two different shaped electrodes, the coated double flat electrodes (DFE), and double conical electrodes, were studied. We showed that the signal amplification of coated DFE is around 4 times higher than that of uncoated electrodes without VUV light reflection. The relationship between the pressure of ionization chamber and mass signal enhancement has also been studied.

  3. Hot cells of the Osiris reactor

    International Nuclear Information System (INIS)

    Jourdain, Jean

    1969-10-01

    Hot cells of the Osiris reactor are β and γ type cells. Their main functions are: the extraction of irradiated samples from experimental assemblies (irradiation loops, experimental devices) used to irradiate them, the reinstallation of experimental setups with irradiated samples, the fractioning of unrecoverable experimental devices, and the removal of irradiated samples and active wastes. Each cell is therefore equipped with means for remote handling, for observation and for removal, and a venting. Each cell may also receive additional equipment, notably for the dismantling of experimental setups. This report presents the cell implantation in the reactor, elements to be handled in cells, the path followed by elements to be handled (arrival, departure, conveyors). It describes the cells (capacity and protection, design and construction, external and internal arrangements) and the cell equipment (remote handling devices, windows, lighting, lifting unit, sound system), and the installed electric power. A realisation planning is provided. An appendix indicates the cost of these hot cells

  4. Relativistic kinetics of baryon production in hot Universe

    International Nuclear Information System (INIS)

    Ignat'ev, Yu.G.

    1985-01-01

    The process of baryon production in the hot Universe is investigated in the framework of the relativistic kinetic theory. The exact solution of kinetic equations for supermassive bosons is obtained, thus giving the possibility to correct the results of previous papers: the known optimum domain of baryon production m sub(X) > α sub(X)msub(PI)√N js complemented by the small-mass boson domain, m sub(X) << α sub(X) m sub(PI)√N; as a result, the cosmological lower-limit restriction on the superheavy bosons masses js removed

  5. Neutrino mass from laboratory: contribution of double beta decay to the neutrino mass matrix

    International Nuclear Information System (INIS)

    Klapdor-Kleingrothaus, H.V.

    2001-01-01

    Double beta decay is indispensable to solve the question of the neutrino mass matrix together with ν oscillation experiments. The most sensitive experiment - since eight years the HEIDELBERG-MOSCOW experiment in Gran-Sasso - already now, with the experimental limit of ν > < 0.26 eV practically excludes degenerate ν mass scenarios allowing neutrinos as hot dark matter in the universe for the smallangle MSW solution of the solar neutrino problem. It probes cosmological models including hot dark matter already now on the level of future satellite experiments MAP and PLANCK. It further probes many topics of beyond SM physics at the TeV scale. Future experiments should give access to the multi-TeV range and complement on many ways the search for new physics at future colliders like LHC and NLC. For neutrino physics some of them (GENIUS) will allow to test almost all neutrino mass scenarios allowed by the present neutrino oscillation experiments

  6. HOT 2011

    DEFF Research Database (Denmark)

    Lund, Henriette Romme

    En undersøgelse af, hvad der er hot - og burde være hot på læseområdet. I undersøgelsen deltager 21 læsekyndige fra praksisfeltet, professionshøjskolerne og forskningsområdet.......En undersøgelse af, hvad der er hot - og burde være hot på læseområdet. I undersøgelsen deltager 21 læsekyndige fra praksisfeltet, professionshøjskolerne og forskningsområdet....

  7. Reduction in biomass burning aerosol light absorption upon humidification: roles of inorganically-induced hygroscopicity, particle collapse, and photoacoustic heat and mass transfer

    Directory of Open Access Journals (Sweden)

    L. Liu

    2009-11-01

    Full Text Available Smoke particle emissions from the combustion of biomass fuels typical for the western and southeastern United States were studied and compared under high humidity and ambient conditions in the laboratory. The fuels used were Montana ponderosa pine (Pinus ponderosa, southern California chamise (Adenostoma fasciculatum, and Florida saw palmetto (Serenoa repens. Information on the non-refractory chemical composition of biomass burning aerosol from each fuel was obtained with an aerosol mass spectrometer and through estimation of the black carbon concentration from light absorption measurements at 870 nm. Changes in the optical and physical particle properties under high humidity conditions were observed for hygroscopic smoke particles containing substantial inorganic mass fractions that were emitted from combustion of chamise and palmetto fuels. Light scattering cross sections increased under high humidity for these particles, consistent with the hygroscopic growth measured for 100 nm particles in HTDMA measurements. Photoacoustic measurements of aerosol light absorption coefficients revealed a 20% reduction with increasing relative humidity, contrary to the expectation of light absorption enhancement by the liquid coating taken up by hygroscopic particles. This reduction is hypothesized to arise from two mechanisms: (1 shielding of inner monomers after particle consolidation or collapse with water uptake; (2 the lower case contribution of mass transfer through evaporation and condensation at high relative humidity (RH to the usual heat transfer pathway for energy release by laser-heated particles in the photoacoustic measurement of aerosol light absorption. The mass transfer contribution is used to evaluate the fraction of aerosol surface covered with liquid water solution as a function of RH.

  8. Mass loss from Eta Carinae

    International Nuclear Information System (INIS)

    Andriesse, C.D.; Viotti, R.

    1979-01-01

    This high luminosity (5x10 6 solar luminosity) star since 1840 is losing mass at the rate of 7.5x10 -2 solar masses per year. The large mass loss could be the result of vibrational instabilities produced in the CNO hydrogen burning phase of a very massive (160 solar masses) star. The presence of high excitation lines in the ultraviolet spectrum of Eta Car suggests the idea of a hot zone excited by dissipation of the supersonic turbulent flow. (Auth.)

  9. Role of hot electron transport in scintillators: A theoretical study

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Huihui [SZU-NUS Collaborative Innovation Center for Optoelectronic Science and Technology, Key Lab. of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen Univ. (China); Li, Qi [Physical Sciences Division, IBM TJ Watson Research Center, Yorktown Heights, NY (United States); Department of Computer Science, University of Illinois at Urbana-Champaign, Urbana, IL (United States); Lu, Xinfu; Williams, R.T. [Department of Physics, Wake Forest University, Winston Salem, NC (United States); Qian, Yiyang [College of Engineering and Applied Science, Nanjing University (China); Wu, Yuntao [Scintillation Materials Research Center, University of Tennessee, Knoxville, TN (United States)

    2016-10-15

    Despite recent intensive study on scintillators, several fundamental questions on scintillator properties are still unknown. In this work, we use ab-initio calculations to determine the energy dependent group velocity of the hot electrons from the electronic structures of several typical scintillators. Based on the calculated group velocities and optical phonon frequencies, a Monte-Carlo simulation of hot electron transport in scintillators is carried out to calculate the thermalization time and diffusion range in selected scintillators. Our simulations provide physical insights on a recent trend of improved proportionality and light yield from mixed halide scintillators. (copyright 2016 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Big bang photosynthesis and pregalactic nucleosynthesis of light elements

    Science.gov (United States)

    Audouze, J.; Lindley, D.; Silk, J.

    1985-01-01

    Two nonstandard scenarios for pregalactic synthesis of the light elements (H-2, He-3, He-4, and Li-7) are developed. Big bang photosynthesis occurs if energetic photons, produced by the decay of massive neutrinos or gravitinos, partially photodisintegrate He-4 (formed in the standard hot big bang) to produce H-2 and He-3. In this case, primordial nucleosynthesis no longer constrains the baryon density of the universe, or the number of neutrino species. Alternatively, one may dispense partially or completely with the hot big bang and produce the light elements by bombardment of primordial gas, provided that He-4 is synthesized by a later generation of massive stars.

  11. Big bang photosynthesis and pregalactic nucleosynthesis of light elements

    International Nuclear Information System (INIS)

    Audouze, J.; Lindley, D.; Silk, J.; and Laboratoire Rene Bernas, Orsay, France)

    1985-01-01

    Two nonstandard scenarios for pregalactic synthesis of the light elements ( 2 H, 3 He, 4 He, and 7 Li) are developed. Big bang photosynthesis occurs if energetic photons, produced by the decay of massive neutrinos or gravitinos, partially photodisintegrate 4 He (formed in the standard hot big bang) to produce 2 H and 3 He. In this case, primordial nucleosynthesis no longer constrains the baryon density of the universe, or the number of neutrino species. Alternatively, one may dispense partially or completely with the hot big bang and produce the light elements by bombardment of primordial gas, provided that 4 He is synthesized by a later generation of massive stars

  12. Mass spectrometry footprinting reveals the structural rearrangements of cyanobacterial orange carotenoid protein upon light activation

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Haijun [Washington University; Zhang, Hao [Washington University; King, Jeremy D. [Washington University; Wolf, Nathan R. [Washington University; Prado, Mindy [Washington University; Gross, Michael L. [Washington University; Blankenship, Robert E. [Washington University

    2014-12-01

    The orange carotenoid protein (OCP), a member of the family of blue light photoactive proteins, is required for efficient photoprotection in many cyanobacteria. Photoexcitation of the carotenoid in the OCP results in structural changes within the chromophore and the protein to give an active red form of OCP that is required for phycobilisome binding and consequent fluorescence quenching. We characterized the light-dependent structural changes by mass spectrometry-based carboxyl footprinting and found that an α helix in the N-terminal extension of OCP plays a key role in this photoactivation process. Although this helix is located on and associates with the outside of the β-sheet core in the C-terminal domain of OCP in the dark, photoinduced changes in the domain structure disrupt this interaction. We propose that this mechanism couples light-dependent carotenoid conformational changes to global protein conformational dynamics in favor of functional phycobilisome binding, and is an essential part of the OCP photocycle.

  13. About the effect of melted zinc mass additives on the formation on layers during hot galvanizing; Zur Wirkung von Zusaetzen zur Zinkschmelze auf die Schichtbildung beim Feuerverzinken

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, P.; Schulz, W.D. [Institut fuer Korrosionsschutz Dresden GmbH, Gostritzer Str. 61-63, D-01217 Dresden (Germany)

    2002-09-01

    The influence of various melted zinc mass additives on the galvanizing behaviour of steels is examined by way of comparison. The mechanisms influencing the formation of layers are very different. In case tin is added, a material barrier of enriched tin develops in the zinc coating, which inhibits the iron transport. The mechanisms of Ni, Ti and Al in the melted zinc mass are explained by means of a new theory on the formation of layers, which is based on the influence of the growth of layers via hydrogen escaping from the steel surface during hot galvanizing. This behaviour makes it clear why the single melted mass additives only have a layer-thickness reducing effect on steels with very definite Si contents. The different inhibitions of the growth of the layer during hot galvanizing are discussed. (Abstract Copyright[2002], Wiley Periodicals, Inc.) [German] Der Einfluss unterschiedlicher Zinkschmelzezusaetze auf das Verzinkungsverhalten der Staehle wird vergleichend untersucht. Die Mechanismen der Einflussnahme auf die Schichtbildung sind sehr unterschiedlich. Bei Zusatz von Zinn entsteht im Zinkueberzug eine Materialbarriere aus angereichertem Zinn, die den Eisentransport hemmt. Die Wirkungsweise von Ni, Ti und Al in der Zinkschmelze wird mit Hilfe einer neuen Theorie der Schichtbildung erklaert. Diese beruht auf der Beeinflussung des Schichtwachstums durch Wasserstoff, der waehrend des Feuerverzinkens aus der Stahloberflaeche austritt. Diese Erklaerung macht verstaendlich, warum die einzelnen Schmelzezusaetze nur bei Staehlen mit ganz bestimmten Si-Gehalten schichtdickenreduzierend wirken. Die unterschiedlichen Hemmungen des Schichtwachstums beim Feuerverzinken werden diskutiert. (Abstract Copyright[2002], Wiley Periodicals, Inc.)

  14. Hot metastable state of abnormal matter in relativistic nuclear field theory

    International Nuclear Information System (INIS)

    Glendenning, N.K.

    1987-01-01

    Because of their non-linearity, the field equations of relativistic nuclear field theory admit of additional solutions besides the normal state of matter. One of these is a finite-temperature abnormal phase. Over a narrow range in temperature, matter can exist in the abnormal phase at zero pressure. This is a hot metastable state, for which there is a barrier against decay, because the field configuration is different than in the normal state, the baryon masses are far removed from their vacuum masses, there is an abundance of pairs also far removed from their vacuum masses, and a correspondingly high entropy. The abundance of baryon-antibaryon pairs is the glue that holds this matter together. The signals associated with this novel state are quite unusual. A fragment of such matter will cool by emitting a spectrum of black-body radiation, consisting principally of photons, lepton pairs and pions, rather than by baryon emission, because the latter are far removed from their vacuum masses. If produced at the upper end of its temperature range, a large fraction of the original energy, more than half in the examples studied here, is radiated in this way. The baryons and light elements produced in the eventual decay, after the abnormal matter has cooled to a domain where its pressure becomes positive, will account for only a fraction of the original energy. The energy domain of this state depends sensitively on the coupling constants, and within a reasonable range as determined by nuclear matter properties, can lie in the range of GeV to tens of GeV per nucleon. (orig.)

  15. Processing hot-dip galvanized AHSS grades: a challenging task

    Energy Technology Data Exchange (ETDEWEB)

    Pichler, A.; Hebesberger, T.; Tragl, E.; Traint, S.; Faderl, J.; Angeli, G.; Koesters, K. [voestalpine Stahl GmbH, Linz (Austria)

    2005-07-01

    High-strength thin sheet steel grades have gained a considerable market share. At present a very strong demand has been observed for DP (dual-phase), CP (complex phase) and TRIP grades, which are often summarized as advanced high-strength steel grades (AHSS). The potential benefits of applying AHSS grades were impressively demonstrated in the ULSAC-AVC project, in which a remarkable reduction in mass and an increase in stiffness and crash safety were achieved by using a very high share of AHSS steel grades. The present contribution concentrates on hot-dip galvanized AHSS thin sheet grades. The hot-dip galvanizeability of such grades is critically discussed after an overview is provided of the metallurgy of AHSS grades, including microstructure, mechanical properties, phase transformations and required alloy design. Based on these fundamentals, the processing of AHSS grades in the hot-dip galvanizing line is discussed and the resulting properties presented. (orig.)

  16. High-precision predictions for the light CP-even Higgs boson mass of the minimal supersymmetric standard model.

    Science.gov (United States)

    Hahn, T; Heinemeyer, S; Hollik, W; Rzehak, H; Weiglein, G

    2014-04-11

    For the interpretation of the signal discovered in the Higgs searches at the LHC it will be crucial in particular to discriminate between the minimal Higgs sector realized in the standard model (SM) and its most commonly studied extension, the minimal supersymmetric standard model (MSSM). The measured mass value, having already reached the level of a precision observable with an experimental accuracy of about 500 MeV, plays an important role in this context. In the MSSM the mass of the light CP-even Higgs boson, Mh, can directly be predicted from the other parameters of the model. The accuracy of this prediction should at least match the one of the experimental result. The relatively high mass value of about 126 GeV has led to many investigations where the scalar top quarks are in the multi-TeV range. We improve the prediction for Mh in the MSSM by combining the existing fixed-order result, comprising the full one-loop and leading and subleading two-loop corrections, with a resummation of the leading and subleading logarithmic contributions from the scalar top sector to all orders. In this way for the first time a high-precision prediction for the mass of the light CP-even Higgs boson in the MSSM is possible all the way up to the multi-TeV region of the relevant supersymmetric particles. The results are included in the code FEYNHIGGS.

  17. BLACK HOLE-NEUTRON STAR MERGERS WITH A HOT NUCLEAR EQUATION OF STATE: OUTFLOW AND NEUTRINO-COOLED DISK FOR A LOW-MASS, HIGH-SPIN CASE

    Energy Technology Data Exchange (ETDEWEB)

    Deaton, M. Brett; Duez, Matthew D. [Department of Physics and Astronomy, Washington State University, Pullman, WA 99164 (United States); Foucart, Francois; O' Connor, Evan [Canadian Institute for Theoretical Astrophysics, University of Toronto, Toronto, Ontario M5S 3H8 (Canada); Ott, Christian D.; Scheel, Mark A.; Szilagyi, Bela [TAPIR, MC 350-17, California Institute of Technology, Pasadena, CA 91125 (United States); Kidder, Lawrence E.; Muhlberger, Curran D., E-mail: mbdeaton@wsu.edu, E-mail: m.duez@wsu.edu [Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853 (United States)

    2013-10-10

    Neutrino emission significantly affects the evolution of the accretion tori formed in black hole-neutron star mergers. It removes energy from the disk, alters its composition, and provides a potential power source for a gamma-ray burst. To study these effects, simulations in general relativity with a hot microphysical equation of state (EOS) and neutrino feedback are needed. We present the first such simulation, using a neutrino leakage scheme for cooling to capture the most essential effects and considering a moderate mass (1.4 M{sub ☉} neutron star, 5.6 M{sub ☉} black hole), high-spin (black hole J/M {sup 2} = 0.9) system with the K{sub 0} = 220 MeV Lattimer-Swesty EOS. We find that about 0.08 M{sub ☉} of nuclear matter is ejected from the system, while another 0.3 M{sub ☉} forms a hot, compact accretion disk. The primary effects of the escaping neutrinos are (1) to make the disk much denser and more compact, (2) to cause the average electron fraction Y{sub e} of the disk to rise to about 0.2 and then gradually decrease again, and (3) to gradually cool the disk. The disk is initially hot (T ∼ 6 MeV) and luminous in neutrinos (L{sub ν} ∼ 10{sup 54} erg s{sup –1}), but the neutrino luminosity decreases by an order of magnitude over 50 ms of post-merger evolution.

  18. The Cosmic Microwave Background: Detection and Interpretation of the First Light

    Science.gov (United States)

    Wollack, Edward J.

    2016-01-01

    A host of astrophysical observations suggest the early Universe was incredibly hot, dense, and homogeneous. A powerful and useful probe of this epoch is provided by the relic radiation, which we refer to today as the Cosmic Microwave Background (CMB). Precision maps of this light contain the earliest glimpse of the Universe after the Big Bang and signatures of the evolution of its contents. By exploiting these clues, constraints on the age, mass density, detailed composition, and geometry of the Universe can be made. A brief survey of the evolution of the radiometric and polarimetric imaging systems used in advancing our understanding of the early Universe will be reviewed. A survey of detector technologies, instrumentation techniques, and experimental challenges encountered in these efforts will be presented.

  19. Dynamics of a hot (T∼107 K) gas cloud with volume energy losses

    International Nuclear Information System (INIS)

    Suchkov, A.A.; Berman, V.G.; Mishurov, Yu.N.

    1987-01-01

    The dynamics of a hot (T=10 6 -5x10 7 K) gas cloud with volume energy losses is investigated by numerical integration of gas dynamics equations. The dynamics is governed by a spherically symmetric gravitational field of the cloud and additional ''hidden'' mass. The cloud mass is taken in the range M 0 =10 10 -10 12 M sun , its radius R 0 =50-200 kpc, the ''hidden'' mass M ν =10 11 -3x10 13 M sun . The results show that in such sytems a structure can develop in the form of a dense compact nucleus with a radius R s 0 , and an extended rarefied hot envelope with a radius R X ∼ R 0 . Among the models involved are those where the gas cloud is either entirely blown up or entirely collapses; in some models, after the phase of initial expansion, part of the gas mass returns back into the system to form a nucleus and an envelope, and the other part leaves the system. The results are discussed in connection with the formation and early evolution of galaxies, the history of star formation and chemical evolution of galaxies, the origin of hot gas in galaxies and clusters of galaxies. It is suggested that in the real history of galaxies, formation of the nucleus and envelope corresponds to formation of galactic stellar component and X-ray halo

  20. The effects of Hot Pepper Extract and Capsaicin on Adipocyte Metabolism

    Directory of Open Access Journals (Sweden)

    Ching Sheng, Chu

    2008-03-01

    Full Text Available Objectives : The purpose of this study is to investigate the effects of hot pepper extract and capsaicin on the adipogenesis in 3T3-L1 cells, lipolysis in rat epididymal adipocytes and histological changes in porcine adipose tissue. Methods : Inhibiton of preadipocyte differentiation and/or stimulation of lipolysis play important roles in reducing obesity. 3T3-L1 preadipocytes were differentiated with adipogenic reagents by incubating for 3 days in the absence or presence of hot pepper extract or capsaicin ranging from 0.01 to 1㎎/㎖. The effects of hot pepper extract and capsaicin on adipogenesis were examined by measuring GPDH activity and by Oil Red O staining. Mature adipocytes from rat epididymal fat pad was incubated with hot pepper extract or capsaicin ranging from 0.01 to 1㎎/㎖ for 3 hrs. The effects of hot pepper extract and capsaicin on lipolysis were examined by measuring free glycerol released. Fat tissue from pig skin was injected with hot pepper extract or capsaicinCFP ranging from 0.1 to 10㎎/㎖ to examine the effects of hot pepper extract and capsaicin on histological changes under light microscopy. Results : The following results were obtained from present study on adipogenesis of preadipocytes, lipolysis of adipocytes and histological changes in fat tissue. 1. Hot pepper extract and capsaicin inhibited adipogenic differentiation at the concentration of 0.1 and 0.01㎎/㎖, respectively, indicating that capsaicin was more effective in inhibiting adipogenesis than hot pepper extract. 2. Hot pepper extract and capsaicin decreased the activity of glycerol-3-phosphate dehydrogenase(GPDH at the concentration of 0.1 and 0.01㎎/㎖, respectively, indicating that capsaicin was more effective in inhibiting adipogenic differentiation than hot pepper extract. 3. Hot pepper extract and capsaicin increased glycerol release at the concentration of 0.1㎎/㎖. There was no difference in lipolytic activity between hot pepper extract and

  1. HOT 2014

    DEFF Research Database (Denmark)

    Lund, Henriette

    Undersøgelse af, hvad der er hot - og hvad der burde være hot på læseområdet med 21 læsekyndige. Undersøgelsen er gennemført siden 2010. HOT-undersøgelsen er foretaget af Nationalt Videncenter for Læsning - Professionshøjskolerne i samarb. med Dansklærerforeningen...

  2. Arsenic species determination in human scalp hair by pressurized hot water extraction and high performance liquid chromatography-inductively coupled plasma-mass spectrometry.

    Science.gov (United States)

    Morado Piñeiro, Andrés; Moreda-Piñeiro, Jorge; Alonso-Rodríguez, Elia; López-Mahía, Purificación; Muniategui-Lorenzo, Soledad; Prada-Rodríguez, Darío

    2013-02-15

    Analytical methods for the determination of total arsenic and arsenic species (mainly As(III) and As(V)) in human scalp hair have been developed. Inductively coupled plasma-mass spectrometry (ICP-MS) and high performance liquid chromatography (HPLC) coupled to ICP-MS have been used for total arsenic and arsenic species determination, respectively. The proposed methods include a "green", fast, high efficient and automated species leaching procedure by pressurized hot water extraction (PHWE). The operating parameters for PHWE including modifier concentration, extraction temperature, static time, extraction steps, pressure, mean particle size, diatomaceous earth (DE) mass/sample mass ratio and flush volume were studied using design of experiments (Plackett-Burman design PBD). Optimum condition implies a modifier concentration (acetic acid) of 150 mM and powdered hair samples fully mixed with diatomaceous earth (DE) as a dispersing agent at a DE mass/sample mass ratio of 5. The extraction has been carried out at 100°C and at an extraction pressure of 1500 psi for 5 min in four extraction step. Under optimised conditions, limits of quantification of 7.0, 6.3 and 50.3 ng g(-1) for total As, As(III) and As(V), respectively were achieved. Repeatability of the overall procedure (4.4, 7.2 and 2.1% for total As, As(III) and As(V), respectively) was achieved. The analysis of GBW-07601 (human hair) certified reference material was used for validation. The optimised method has been finally applied to several human scalp hair samples. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Cosmological N -body simulations with generic hot dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Brandbyge, Jacob; Hannestad, Steen, E-mail: jacobb@phys.au.dk, E-mail: sth@phys.au.dk [Department of Physics and Astronomy, University of Aarhus, Ny Munkegade 120, DK–8000 Aarhus C (Denmark)

    2017-10-01

    We have calculated the non-linear effects of generic fermionic and bosonic hot dark matter components in cosmological N -body simulations. For sub-eV masses, the non-linear power spectrum suppression caused by thermal free-streaming resembles the one seen for massive neutrinos, whereas for masses larger than 1 eV, the non-linear relative suppression of power is smaller than in linear theory. We furthermore find that in the non-linear regime, one can map fermionic to bosonic models by performing a simple transformation.

  4. On the relativistic mass conception

    International Nuclear Information System (INIS)

    Kard, P.

    1979-01-01

    Mass of light is generally substantiated with the use of the Einstein known mental experiment with a cylinder displacing under the pressure of light flare emitted at one of its ends and absorbed at the other. This experiment is not rigorous however and involves a logical circle. Another method is presented to substantiate mass of light. The initial conditions are as follows: the law of momentum conservation, evailability of light pulse, momentum parallelism to a velocity, and the general ralativistic formula of velocity transformation. A consideration is given to directed emission of light flux by a body in two internal systems, viz. in the system of initial rest of the body and in the system moving relatively to it with an arbitrary velocity. The law of momentum conservation being used in both systems, as well as formulae for velocity transformation, the formulae are obtained which show that light has mass. The general law of mass conservation is derived as a consequence of the formulae for mass and momentum transformations

  5. Evaluation of Dietary Intake of Various Vitamins in Menopausal Women with Hot Flashes

    Directory of Open Access Journals (Sweden)

    Aytekin Tokmak

    2014-12-01

    Full Text Available Aim: Menopausal hot flashes affect the majority of women. Hormone replacement therapy to reduce the severity of hot flashes is the most effective method. Today, however, due to a number of side effects of hormone therapy more women are seeking alternative treatments such as vitamin pills and herbal products. Previously, various vitamins, minerals and trace elements were studied for this purpose. In this study, our aim was to determine the level of dietary intake of various vitamins in women with hot flashes and to compare them with women who had no complaints. Material and Method: One hundred and seven consecutive women who attended the menopause clinic of our hospital for routine follow up were included in this study. All of the participants were asked about the occurrence of specific menopausal symptoms and completed 92-itm antioxidant nutrient questionnaire developed by Satia. The main parameters recorded for each woman were; age, obstetrical characteristics, body mass index, smoking status, educational level, type of menopause (surgical or natural, duration of menopause, menopausal symptoms, and number and duration of hot flashes. According to the computerized analysis of questionnaire, dietary intake of water-soluble vitamins; B complex and vitamin C, and fat-soluble vitamins; vitamin, A D, E, K were calculated. Results: Patients were divided into two groups with regard to presence of hot flashes, those with hot flashes constituted the study groups (n:75, and others without hot flashes constituted the control group (n:32. The mean age of patients was statistically significantly lower in the study group (p<0,001. The mean duration of menopause was also lower in this group (p<0,001. There were no statistically significant differences between groups in terms of obstetrical characteristics, body mass index, smoking status, educational level, type of menopause (p>0,05. Night sweats and sleep disorders were more common in women with hot flashes

  6. Evaluation of Dietary Intake of Various Vitamins in Menopausal Women with Hot Flashes

    Directory of Open Access Journals (Sweden)

    Aytekin Tokmak

    2016-11-01

    Full Text Available Aim: Menopausal hot flashes affect the majority of women. Hormone replacement therapy to reduce the severity of hot flashes is the most effective method. Today, however, due to a number of side effects of hormone therapy more women are seeking alternative treatments such as vitamin pills and herbal products. Previously, various vitamins, minerals and trace elements were studied for this purpose. In this study, our aim was to determine the level of dietary intake of various vitamins in women with hot flashes and to compare them with women who had no complaints. Material and Method: One hundred and seven consecutive women who attended the menopause clinic of our hospital for routine follow up were included in this study. All of the participants were asked about the occurrence of specific menopausal symptoms and completed 92-itm antioxidant nutrient questionnaire developed by Satia. The main parameters recorded for each woman were; age, obstetrical characteristics, body mass index, smoking status, educational level, type of menopause (surgical or natural, duration of menopause, menopausal symptoms, and number and duration of hot flashes. According to the computerized analysis of questionnaire, dietary intake of water-soluble vitamins; B complex and vitamin C, and fat-soluble vitamins; vitamin, A D, E, K were calculated. Results: Patients were divided into two groups with regard to presence of hot flashes, those with hot flashes constituted the study groups (n:75, and others without hot flashes constituted the control group (n:32. The mean age of patients was statistically significantly lower in the study group (p<0,001. The mean duration of menopause was also lower in this group (p<0,001. There were no statistically significant differences between groups in terms of obstetrical characteristics, body mass index, smoking status, educational level, type of menopause (p>0,05. Night sweats and sleep disorders were more common in women with hot flashes

  7. Very light dilaton and naturally light Higgs boson

    Science.gov (United States)

    Hong, Deog Ki

    2018-02-01

    We study very light dilaton, arising from a scale-invariant ultraviolet theory of the Higgs sector in the standard model of particle physics. Imposing the scale symmetry below the ultraviolet scale of the Higgs sector, we alleviate the fine-tuning problem associated with the Higgs mass. When the electroweak symmetry is spontaneously broken radiatively à la Coleman-Weinberg, the dilaton develops a vacuum expectation value away from the origin to give an extra contribution to the Higgs potential so that the Higgs mass becomes naturally around the electroweak scale. The ultraviolet scale of the Higgs sector can be therefore much higher than the electroweak scale, as the dilaton drives the Higgs mass to the electroweak scale. We also show that the light dilaton in this scenario is a good candidate for dark matter of mass m D ˜ 1 eV - 10 keV, if the ultraviolet scale is about 10-100 TeV. Finally we propose a dilaton-assisted composite Higgs model to realize our scenario. In addition to the light dilaton the model predicts a heavy U(1) axial vector boson and two massive, oppositely charged, pseudo Nambu-Goldstone bosons, which might be accessible at LHC.

  8. Capability and opportunity in hot shooting performance: Evidence from top-scoring NBA leaders.

    Science.gov (United States)

    Chang, Shun-Chuan

    2018-01-01

    In basketball games, whenever players successfully shoot in streaks, they are expected to demonstrate heightened performance for a stretch of time. Streak shooting in basketball has been debated for more than three decades, but most studies have provided little significant statistical evidence and have labeled random subjective judgments the "hot hand fallacy." To obtain a broader perspective of the hot hand phenomenon and its accompanying influences on the court, this study uses field goal records and optical tracking data from the official NBA database for the entire 2015-2016 season to analyze top-scoring leaders' shooting performances. We first reflect on the meaning of "hot hand" and the "Matthew effect" in actual basketball competition. Second, this study employs statistical models to integrate three different shooting perspectives (field goal percentage, points scored, and attempts). This study's findings shed new light not only on the existence or nonexistence of streaks, but on the roles of capability and opportunity in NBA hot shooting. Furthermore, we show how hot shooting performances resulting from capability and opportunity lead to actual differences for teams.

  9. Capability and opportunity in hot shooting performance: Evidence from top-scoring NBA leaders.

    Directory of Open Access Journals (Sweden)

    Shun-Chuan Chang

    Full Text Available In basketball games, whenever players successfully shoot in streaks, they are expected to demonstrate heightened performance for a stretch of time. Streak shooting in basketball has been debated for more than three decades, but most studies have provided little significant statistical evidence and have labeled random subjective judgments the "hot hand fallacy." To obtain a broader perspective of the hot hand phenomenon and its accompanying influences on the court, this study uses field goal records and optical tracking data from the official NBA database for the entire 2015-2016 season to analyze top-scoring leaders' shooting performances. We first reflect on the meaning of "hot hand" and the "Matthew effect" in actual basketball competition. Second, this study employs statistical models to integrate three different shooting perspectives (field goal percentage, points scored, and attempts. This study's findings shed new light not only on the existence or nonexistence of streaks, but on the roles of capability and opportunity in NBA hot shooting. Furthermore, we show how hot shooting performances resulting from capability and opportunity lead to actual differences for teams.

  10. Designing the Color of Hot-Dip Galvanized Steel Sheet Through Destructive Light Interference Using a Zn-Ti Liquid Metallic Bath

    Science.gov (United States)

    Levai, Gabor; Godzsák, Melinda; Török, Tamas I.; Hakl, Jozsef; Takáts, Viktor; Csik, Attila; Vad, Kalman; Kaptay, George

    2016-07-01

    The color of hot-dip galvanized steel sheet was adjusted in a reproducible way using a liquid Zn-Ti metallic bath, air atmosphere, and controlling the bath temperature as the only experimental parameter. Coloring was found only for samples cooled in air and dipped into Ti-containing liquid Zn. For samples dipped into a 0.15 wt pct Ti-containing Zn bath, the color remained metallic (gray) below a 792 K (519 °C) bath temperature; it was yellow at 814 K ± 22 K (541 °C ± 22 °C), violet at 847 K ± 10 K (574 °C ± 10 °C), and blue at 873 K ± 15 K (600 °C ± 15 °C). With the increasing bath temperature, the thickness of the adhered Zn-Ti layer gradually decreased from 52 to 32 micrometers, while the thickness of the outer TiO2 layer gradually increased from 24 to 69 nm. Due to small Al contamination of the Zn bath, a thin (around 2 nm) alumina-rich layer is found between the outer TiO2 layer and the inner macroscopic Zn layer. It is proven that the color change was governed by the formation of thin outer TiO2 layer; different colors appear depending on the thickness of this layer, mostly due to the destructive interference of visible light on this transparent nano-layer. A complex model was built to explain the results using known relationships of chemical thermodynamics, adhesion, heat flow, kinetics of chemical reactions, diffusion, and optics. The complex model was able to reproduce the observations and allowed making predictions on the color of the hot-dip galvanized steel sample, as a function of the following experimental parameters: temperature and Ti content of the Zn bath, oxygen content, pressure, temperature and flow rate of the cooling gas, dimensions of the steel sheet, velocity of dipping the steel sheet into the Zn-Ti bath, residence time of the steel sheet within the bath, and the velocity of its removal from the bath. These relationships will be valuable for planning further experiments and technologies on color hot-dip galvanization of steel

  11. Evolution of complex organic molecules in hot molecular cores. Synthetic spectra at (sub-)mm wavebands

    Science.gov (United States)

    Choudhury, R.; Schilke, P.; Stéphan, G.; Bergin, E.; Möller, T.; Schmiedeke, A.; Zernickel, A.

    2015-03-01

    Context. Hot molecular cores (HMCs) are intermediate stages of high-mass star formation and are also known for their rich chemical reservoirs and emission line spectra at (sub-)mm wavebands. Complex organic molecules (COMs) such as methanol (CH3OH), ethanol (C2H5OH), dimethyl ether (CH3OCH3), and methyl formate (HCOOCH3) produce most of these observed lines. The observed spectral feature of HMCs such as total number of emission lines and associated line intensities are also found to vary with evolutionary stages. Aims: We aim to investigate the spectral evolution of these COMs to explore the initial evolutionary stages of high-mass star formation including HMCs. Methods: We developed various 3D models for HMCs guided by the evolutionary scenarios proposed by recent empirical and modeling studies. We then investigated the spatio-temporal variation of temperature and molecular abundances in HMCs by consistently coupling gas-grain chemical evolution with radiative transfer calculations. We explored the effects of varying physical conditions on molecular abundances including density distribution and luminosity evolution of the central protostar(s) among other parameters. Finally, we simulated the synthetic spectra for these models at different evolutionary timescales to compare with observations. Results: Temperature has a profound effect on the formation of COMs through the depletion and diffusion on grain surface to desorption and further gas-phase processing. The time-dependent temperature structure of the hot core models provides a realistic framework for investigating the spatial variation of ice mantle evaporation as a function of evolutionary timescales. We find that a slightly higher value (15 K) than the canonical dark cloud temperature (10 K) provides a more productive environment for COM formation on grain surface. With increasing protostellar luminosity, the water ice evaporation font (~100 K) expands and the spatial distribution of gas phase abundances of

  12. SDSS J14584479+3720215: A BENCHMARK JHK{sub S} BLAZAR LIGHT CURVE FROM THE 2MASS CALIBRATION SCANS

    Energy Technology Data Exchange (ETDEWEB)

    Davenport, James R. A.; Ruan, John J.; Becker, Andrew C. [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States); Macleod, Chelsea L. [Physics Department, The United States Naval Academy, 572c Holloway Road, Annapolis, MD 21402 (United States); Cutri, Roc M., E-mail: jrad@astro.washington.edu [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States)

    2015-04-10

    Active galactic nuclei (AGNs) are well-known to exhibit flux variability across a wide range of wavelength regimes, but the precise origin of the variability at different wavelengths remains unclear. To investigate the relatively unexplored near-IR (NIR) variability of the most luminous AGNs, we conduct a search for variability using well sampled JHK{sub s}-band light curves from the Two Micron All Sky Survey (2MASS) calibration fields. Our sample includes 27 known quasars with an average of 924 epochs of observation over three years, as well as one spectroscopically confirmed blazar (SDSS J14584479+3720215) with 1972 epochs of data. This is the best-sampled NIR photometric blazar light curve to date, and it exhibits correlated, stochastic variability that we characterize with continuous auto-regressive moving average (CARMA) models. None of the other 26 known quasars had detectable variability in the 2MASS bands above the photometric uncertainty. A blind search of the 2MASS calibration field light curves for active galactic nucleus (AGN) candidates based on fitting CARMA(1,0) models (damped-random walk) uncovered only seven candidates. All seven were young stellar objects within the ρ Ophiuchus star forming region, five with previous X-ray detections. A significant γ-ray detection (5σ) for the known blazar using 4.5 yr of Fermi photon data is also found. We suggest that strong NIR variability of blazars, such as seen for SDSS J14584479+3720215, can be used as an efficient method of identifying previously unidentified γ-ray blazars, with low contamination from other AGNs.

  13. Production and desexcitation of hot nuclei in 40Ar + 238U collisions at 27 MeV/u

    International Nuclear Information System (INIS)

    Jacquet, D.

    1987-01-01

    The selection of hot nuclei can be achieved through the folding angle of the coincident fission fragments. At this bombarding energy a distinct fusion component shows up in the folding angle correlation function corresponding to the most central collisions. The mass of the fission fragments decreases with increasing linear momentum transfer; the energy dissipated into the target nucleus is proportional to the momentum transfer. The mass distribution full width at half maximum increases with dissipated energy and this can be understood as the result of thermal fluctuations. The light charged particles detected in coincidence with the fission fragments exhibit, at least backwards, the characteristic behaviour of evaporative particles from a thermally equilibrated source. The fused nucleus is revealed as the dominant emitter. The observed energy spectra can be reproduced in a Monte Carlo type simulation assuming that about 80% of the particles arise from the fused nuclei and only 20 % from the fully accelerated fission fragments. A detailed analysis of the shape of the spectra allows to precise the average characteristics of the emitter: it is quite deformed has a very broad spin distribution and a temperature from 4 to 5 MeV. All these characteristics are consistently deduced in semi-classical dynamical calculations based on the Landau-Vlasov equation. The pre-fission particle emission probabilities are shown to be much larger than would predict a purely statistical model for such heavy and hot nuclei. Such a behaviour can only be understood if the dynamics of the collision is taken into account [fr

  14. POLARIZATION MEASUREMENTS OF HOT DUST STARS AND THE LOCAL INTERSTELLAR MEDIUM

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, J. P.; Cotton, D. V.; Bott, K.; Bailey, J.; Kedziora-Chudczer, L. [School of Physics, UNSW Australia, High Street, Kensington, NSW 2052 (Australia); Ertel, S. [Steward Observatory, Department of Astronomy, University of Arizona, 933 N. Cherry Avenue, Tucson, AZ 85721 (United States); Kennedy, G. M.; Wyatt, M. C. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA (United Kingdom); Burgo, C. del [Instituto Nacional de Astrofísica, Óptica y Electrónica, Luis Enrique Erro 1, Sta. Ma. Tonantzintla, Puebla (Mexico); Absil, O. [Institut d’Astrophysique et de Géophysique, University of Liège, 19c allée du Six Août, B-4000 Liège (Belgium)

    2016-07-10

    Debris discs are typically revealed through the presence of excess emission at infrared wavelengths. Most discs exhibit excess at mid- and far-infrared wavelengths, analogous to the solar system’s Asteroid and Edgeworth-Kuiper belts. Recently, stars with strong (∼1%) excess at near-infrared wavelengths were identified through interferometric measurements. Using the HIgh Precision Polarimetric Instrument, we examined a sub-sample of these hot dust stars (and appropriate controls) at parts-per-million sensitivity in SDSS g ′ (green) and r ′ (red) filters for evidence of scattered light. No detection of strongly polarized emission from the hot dust stars is seen. We, therefore, rule out scattered light from a normal debris disk as the origin of this emission. A wavelength-dependent contribution from multiple dust components for hot dust stars is inferred from the dispersion (the difference in polarization angle in red and green) of southern stars. Contributions of 17 ppm (green) and 30 ppm (red) are calculated, with strict 3- σ upper limits of 76 and 68 ppm, respectively. This suggests weak hot dust excesses consistent with thermal emission, although we cannot rule out contrived scenarios, e.g., dust in a spherical shell or face-on discs. We also report on the nature of the local interstellar medium (ISM), obtained as a byproduct of the control measurements. Highlights include the first measurements of the polarimetric color of the local ISM and the discovery of a southern sky region with a polarization per distance thrice the previous maximum. The data suggest that λ {sub max}, the wavelength of maximum polarization, is bluer than typical.

  15. Efficient, Broadband and Wide-Angle Hot-Electron Transduction using Metal-Semiconductor Hyperbolic Metamaterials

    KAUST Repository

    Sakhdari, Maryam

    2016-05-20

    Hot-electron devices are emerging as promising candidates for the transduction of optical radiation into electrical current, as they enable photodetection and solar/infrared energy harvesting at sub-bandgap wavelengths. Nevertheless, poor photoconversion quantum yields and low bandwidth pose fundamental challenge to fascinating applications of hot-electron optoelectronics. Based on a novel hyperbolic metamaterial (HMM) structure, we theoretically propose a vertically-integrated hot-electron device that can efficiently couple plasmonic excitations into electron flows, with an external quantum efficiency approaching the physical limit. Further, this metamaterial-based device can have a broadband and omnidirectional response at infrared and visible wavelengths. We believe that these findings may shed some light on designing practical devices for energy-efficient photodetection and energy harvesting beyond the bandgap spectral limit.

  16. RADIO EMISSION FROM RED-GIANT HOT JUPITERS

    International Nuclear Information System (INIS)

    Fujii, Yuka; Spiegel, David S.; Mroczkowski, Tony; Nordhaus, Jason; Zimmerman, Neil T.; Parsons, Aaron R.; Mirbabayi, Mehrdad; Madhusudhan, Nikku

    2016-01-01

    When planet-hosting stars evolve off the main sequence and go through the red-giant branch, the stars become orders of magnitudes more luminous and, at the same time, lose mass at much higher rates than their main-sequence counterparts. Accordingly, if planetary companions exist around these stars at orbital distances of a few au, they will be heated up to the level of canonical hot Jupiters and also be subjected to a dense stellar wind. Given that magnetized planets interacting with stellar winds emit radio waves, such “Red-Giant Hot Jupiters” (RGHJs) may also be candidate radio emitters. We estimate the spectral auroral radio intensity of RGHJs based on the empirical relation with the stellar wind as well as a proposed scaling for planetary magnetic fields. RGHJs might be intrinsically as bright as or brighter than canonical hot Jupiters and about 100 times brighter than equivalent objects around main-sequence stars. We examine the capabilities of low-frequency radio observatories to detect this emission and find that the signal from an RGHJ may be detectable at distances up to a few hundred parsecs with the Square Kilometer Array

  17. RADIO EMISSION FROM RED-GIANT HOT JUPITERS

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Yuka [Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, 152-8550 (Japan); Spiegel, David S. [Analytics and Algorithms, Stitch Fix, San Francisco, CA 94103 (United States); Mroczkowski, Tony [Naval Research Laboratory, 4555 Overlook Ave SW, Washington, DC 20375 (United States); Nordhaus, Jason [Department of Science and Mathematics, National Technical Institute for the Deaf, Rochester Institute of Technology, Rochester, NY 14623 (United States); Zimmerman, Neil T. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Parsons, Aaron R. [Astronomy Department, University of California, Berkeley, CA (United States); Mirbabayi, Mehrdad [Astrophysics Department, Institute for Advanced Study, Princeton, NJ 08540 (United States); Madhusudhan, Nikku, E-mail: yuka.fujii@elsi.jp [Astronomy Department, University of Cambridge (United Kingdom)

    2016-04-01

    When planet-hosting stars evolve off the main sequence and go through the red-giant branch, the stars become orders of magnitudes more luminous and, at the same time, lose mass at much higher rates than their main-sequence counterparts. Accordingly, if planetary companions exist around these stars at orbital distances of a few au, they will be heated up to the level of canonical hot Jupiters and also be subjected to a dense stellar wind. Given that magnetized planets interacting with stellar winds emit radio waves, such “Red-Giant Hot Jupiters” (RGHJs) may also be candidate radio emitters. We estimate the spectral auroral radio intensity of RGHJs based on the empirical relation with the stellar wind as well as a proposed scaling for planetary magnetic fields. RGHJs might be intrinsically as bright as or brighter than canonical hot Jupiters and about 100 times brighter than equivalent objects around main-sequence stars. We examine the capabilities of low-frequency radio observatories to detect this emission and find that the signal from an RGHJ may be detectable at distances up to a few hundred parsecs with the Square Kilometer Array.

  18. Radio Emission from Red-Giant Hot Jupiters

    Science.gov (United States)

    Fujii, Yuka; Spiegel, David S.; Mroczkowski, Tony; Nordhaus, Jason; Zimmerman, Neil T.; Parsons, Aaron R.; Mirbabayi, Mehrdad; Madhusudhan, Nikku

    2016-01-01

    When planet-hosting stars evolve off the main sequence and go through the red-giant branch, the stars become orders of magnitudes more luminous and, at the same time, lose mass at much higher rates than their main sequence counterparts. Accordingly, if planetary companions exist around these stars at orbital distances of a few au, they will be heated up to the level of canonical hot Jupiters and also be subjected to a dense stellar wind. Given that magnetized planets interacting with stellar winds emit radio waves, such "Red-Giant Hot Jupiters" (RGHJs) may also be candidate radio emitters. We estimate the spectral auroral radio intensity of RGHJs based on the empirical relation with the stellar wind as well as a proposed scaling for planetary magnetic fields. RGHJs might be intrinsically as bright as or brighter than canonical hot Jupiters and about 100 times brighter than equivalent objects around main-sequence stars. We examine the capabilities of low-frequency radio observatories to detect this emission and find that the signal from an RGHJ may be detectable at distances up to a few hundred parsecs with the Square Kilometer Array.

  19. Terahertz hot electron bolometer waveguide mixers for GREAT

    OpenAIRE

    Pütz, P.; Honingh, C. E.; Jacobs, K.; Justen, M.; Schultz, M.; Stutzki, J.

    2012-01-01

    Supplementing the publications based on the first-light observations with the German Receiver for Astronomy at Terahertz frequencies (GREAT) on SOFIA, we present background information on the underlying heterodyne detector technology. We describe the superconducting hot electron bolometer (HEB) detectors that are used as frequency mixers in the L1 (1400 GHz), L2 (1900 GHz), and M (2500 GHz) channels of GREAT. Measured performance of the detectors is presented and background information on the...

  20. HOT 2010

    DEFF Research Database (Denmark)

    Lund, Henriette Romme

    En undersøgelse af, hvad der er hot - og burde være hot på læseområdet. I undersøgelsen deltager en række læsekyndige fra praksisfeltet, professionshøjskolerne og forskningsområdet. Undersøgelsen er gentaget hvert år siden 2010.......En undersøgelse af, hvad der er hot - og burde være hot på læseområdet. I undersøgelsen deltager en række læsekyndige fra praksisfeltet, professionshøjskolerne og forskningsområdet. Undersøgelsen er gentaget hvert år siden 2010....

  1. HOT 2013

    DEFF Research Database (Denmark)

    Lund, Henriette Romme

    En undersøgelse af, hvad der er hot - og burde være hot på læseområdet. I undersøgelsen deltager en række læsekyndige fra praksisfeltet, professionshøjskolerne og forskningsområdet. Undersøgelsen er gentaget hvert år siden 2010.......En undersøgelse af, hvad der er hot - og burde være hot på læseområdet. I undersøgelsen deltager en række læsekyndige fra praksisfeltet, professionshøjskolerne og forskningsområdet. Undersøgelsen er gentaget hvert år siden 2010....

  2. Suppression of sawtooth oscillations due to hot electrons and hot ions

    International Nuclear Information System (INIS)

    Zhang, Y.Z.; Berk, H.L.

    1989-01-01

    The theory of m = 1 kink mode stabilization is discussed in the presence of either magnetically trapped hot electrons or hot ions. For instability hot ion requires particles peaked inside the q = 1 surface, while hot electrons require that its pressure profile be increasing at the q = 1 surface. Experimentally observed sawtooth stabilization usually occurs with off-axis heating with ECRH and near axis heating with ICRH. Such heating may produce the magnetically trapped hot particle pressure profiles that are consistent with theory. 17 refs., 2 figs

  3. Amplification of hot electron flow by the surface plasmon effect on metal–insulator–metal nanodiodes

    International Nuclear Information System (INIS)

    Lee, Changhwan; Nedrygailov, Ievgen I; Keun Lee, Young; Lee, Hyosun; Young Park, Jeong; Ahn, Changui; Jeon, Seokwoo

    2015-01-01

    Au–TiO_2–Ti nanodiodes with a metal–insulator–metal structure were used to probe hot electron flows generated upon photon absorption. Hot electrons, generated when light is absorbed in the Au electrode of the nanodiode, can travel across the TiO_2, leading to a photocurrent. Here, we demonstrate amplification of the hot electron flow by (1) localized surface plasmon resonance on plasmonic nanostructures fabricated by annealing the Au–TiO_2–Ti nanodiodes, and (2) reducing the thickness of the TiO_2. We show a correlation between changes in the morphology of the Au electrodes caused by annealing and amplification of the photocurrent. Based on the exponential dependence of the photocurrent on TiO_2 thickness, the transport mechanism for the hot electrons across the nanodiodes is proposed. (paper)

  4. Precise prediction for the light MSSM Higgs-boson mass combining effective field theory and fixed-order calculations

    Energy Technology Data Exchange (ETDEWEB)

    Bahl, Henning; Hollik, Wolfgang [Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Munich (Germany)

    2016-09-15

    In the Minimal Supersymmetric Standard Model heavy superparticles introduce large logarithms in the calculation of the lightest CP-even Higgs-boson mass. These logarithmic contributions can be resummed using effective field theory techniques. For light superparticles, however, fixed-order calculations are expected to be more accurate. To gain a precise prediction also for intermediate mass scales, the two approaches have to be combined. Here, we report on an improvement of this method in various steps: the inclusion of electroweak contributions, of separate electroweakino and gluino thresholds, as well as resummation at the NNLL level. These improvements can lead to significant numerical effects. In most cases, the lightest CP-even Higgs-boson mass is shifted downwards by about 1 GeV. This is mainly caused by higher-order corrections to the MS top-quark mass. We also describe the implementation of the new contributions in the code FeynHiggs. (orig.)

  5. OUTFLOW AND HOT DUST EMISSION IN HIGH-REDSHIFT QUASARS

    International Nuclear Information System (INIS)

    Wang, Huiyuan; Xing, Feijun; Wang, Tinggui; Zhou, Hongyan; Zhang, Kai; Zhang, Shaohua

    2013-01-01

    Correlations of hot dust emission with outflow properties are investigated, based on a large z ∼ 2 non-broad absorption line quasar sample built from the Wide-field Infrared Survey and the Sloan Digital Sky Survey data releases. We use the near-infrared slope and the infrared to UV luminosity ratio to indicate the hot dust emission relative to the emission from the accretion disk. In our luminous quasars, these hot dust emission indicators are almost independent of the fundamental parameters, such as luminosity, Eddington ratio and black hole mass, but moderately dependent on the blueshift and asymmetry index (BAI) and FWHM of C IV lines. Interestingly, the latter two correlations dramatically strengthen with increasing Eddington ratio. We suggest that, in high Eddington ratio quasars, C IV regions are dominated by outflows so the BAI and FWHM (C IV) can reliably reflect the general properties and velocity of outflows, respectively. In low Eddington ratio quasars, on the other hand, C IV lines are primarily emitted by virialized gas so the BAI and FWHM (C IV) become less sensitive to outflows. Therefore, the correlations for the highest Eddington ratio quasars are more likely to represent the true dependence of hot dust emission on outflows and the correlations for the entire sample are significantly diluted by the low Eddington ratio quasars. Our results show that an outflow with a large BAI or velocity can double the hot dust emission on average. We suggest that outflows either contain hot dust in themselves or interact with the dusty interstellar medium or torus

  6. AEOLUS: A MARKOV CHAIN MONTE CARLO CODE FOR MAPPING ULTRACOOL ATMOSPHERES. AN APPLICATION ON JUPITER AND BROWN DWARF HST LIGHT CURVES

    Energy Technology Data Exchange (ETDEWEB)

    Karalidi, Theodora; Apai, Dániel; Schneider, Glenn; Hanson, Jake R. [Steward Observatory, Department of Astronomy, University of Arizona, 933 N. Cherry Avenue, Tucson, AZ 85721 (United States); Pasachoff, Jay M., E-mail: tkaralidi@email.arizona.edu [Hopkins Observatory, Williams College, 33 Lab Campus Drive, Williamstown, MA 01267 (United States)

    2015-11-20

    Deducing the cloud cover and its temporal evolution from the observed planetary spectra and phase curves can give us major insight into the atmospheric dynamics. In this paper, we present Aeolus, a Markov chain Monte Carlo code that maps the structure of brown dwarf and other ultracool atmospheres. We validated Aeolus on a set of unique Jupiter Hubble Space Telescope (HST) light curves. Aeolus accurately retrieves the properties of the major features of the Jovian atmosphere, such as the Great Red Spot and a major 5 μm hot spot. Aeolus is the first mapping code validated on actual observations of a giant planet over a full rotational period. For this study, we applied Aeolus to J- and H-band HST light curves of 2MASS J21392676+0220226 and 2MASS J0136565+093347. Aeolus retrieves three spots at the top of the atmosphere (per observational wavelength) of these two brown dwarfs, with a surface coverage of 21% ± 3% and 20.3% ± 1.5%, respectively. The Jupiter HST light curves will be publicly available via ADS/VIZIR.

  7. Clues on the hot star content and the ultraviolet output of elliptical galaxies

    International Nuclear Information System (INIS)

    Greggio, L.; Renzini, A.

    1990-01-01

    Purely energetic arguments are used here to investigate the conditions under which old, low-mass stars could be responsible for the UV rising branch of elliptical galaxies. It is argued that presently available observational data are insufficient to unambiguously decide which of various candidates provide the dominant contribution. It is found that the possibility for metal-rich, low-mass stars to evolve through sufficiently hot stages, provide enough UV photons, and produce the observed UV-metallicity correlation is primarily controlled by two poorly known trends with increasing metallicity: helium enrichment and mass-loss rate during the red giant phases. The classical hydrogen-burning post-AGB stars do not appear able to burn enough fuel to account for the most UV-powerful galaxies. Other hot star candidates which appear more promising are identified. It is shown that a very important role is played by the actual metallicity distribution within individual galaxies. 154 refs

  8. Ultrasound-Assisted Hot Air Drying of Foods

    Science.gov (United States)

    Mulet, Antonio; Cárcel, Juan Andrés; García-Pérez, José Vicente; Riera, Enrique

    This chapter deals with the application of power ultrasound, also named high-intensity ultrasound, in the hot air drying of foods. The aim of ultrasound-assisted drying is to overcome some of the limitations of traditional convective drying systems, especially by increasing drying rate without reducing quality attributes. The effects of ultrasound on drying rate are responsible for some of the phenomena produced in the internal and/or external resistance to mass transfer.

  9. FRIENDS OF HOT JUPITERS. III. AN INFRARED SPECTROSCOPIC SEARCH FOR LOW-MASS STELLAR COMPANIONS

    Energy Technology Data Exchange (ETDEWEB)

    Piskorz, Danielle; Knutson, Heather A.; Ngo, Henry; Batygin, Konstantin [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA (United States); Muirhead, Philip S. [Institute for Astrophysical Research, Boston University, Boston, MA (United States); Crepp, Justin R. [Department of Physics, University of Notre Dame, South Bend, IN (United States); Hinkley, Sasha [Department of Physics and Astronomy, University of Exeter, Exeter (United Kingdom); Morton, Timothy D., E-mail: dpiskorz@gps.caltech.edu [Department of Astrophysical Sciences, Princeton University, Princeton, NJ (United States)

    2015-12-01

    Surveys of nearby field stars indicate that stellar binaries are common, yet little is known about the effects that these companions may have on planet formation and evolution. The Friends of Hot Jupiters project uses three complementary techniques to search for stellar companions to known planet-hosting stars: radial velocity monitoring, adaptive optics imaging, and near-infrared spectroscopy. In this paper, we examine high-resolution K band infrared spectra of fifty stars hosting gas giant planets on short-period orbits. We use spectral fitting to search for blended lines due to the presence of cool stellar companions in the spectra of our target stars, where we are sensitive to companions with temperatures between 3500 and 5000 K and projected separations less than 100 AU in most systems. We identify eight systems with candidate low-mass companions, including one companion that was independently detected in our AO imaging survey. For systems with radial velocity accelerations, a spectroscopic non-detection rules out scenarios involving a stellar companion in a high inclination orbit. We use these data to place an upper limit on the stellar binary fraction at small projected separations, and show that the observed population of candidate companions is consistent with that of field stars and also with the population of wide-separation companions detected in our previous AO survey. We find no evidence that spectroscopic stellar companions are preferentially located in systems with short-period gas giant planets on eccentric and/or misaligned orbits.

  10. FRIENDS OF HOT JUPITERS. III. AN INFRARED SPECTROSCOPIC SEARCH FOR LOW-MASS STELLAR COMPANIONS

    International Nuclear Information System (INIS)

    Piskorz, Danielle; Knutson, Heather A.; Ngo, Henry; Batygin, Konstantin; Muirhead, Philip S.; Crepp, Justin R.; Hinkley, Sasha; Morton, Timothy D.

    2015-01-01

    Surveys of nearby field stars indicate that stellar binaries are common, yet little is known about the effects that these companions may have on planet formation and evolution. The Friends of Hot Jupiters project uses three complementary techniques to search for stellar companions to known planet-hosting stars: radial velocity monitoring, adaptive optics imaging, and near-infrared spectroscopy. In this paper, we examine high-resolution K band infrared spectra of fifty stars hosting gas giant planets on short-period orbits. We use spectral fitting to search for blended lines due to the presence of cool stellar companions in the spectra of our target stars, where we are sensitive to companions with temperatures between 3500 and 5000 K and projected separations less than 100 AU in most systems. We identify eight systems with candidate low-mass companions, including one companion that was independently detected in our AO imaging survey. For systems with radial velocity accelerations, a spectroscopic non-detection rules out scenarios involving a stellar companion in a high inclination orbit. We use these data to place an upper limit on the stellar binary fraction at small projected separations, and show that the observed population of candidate companions is consistent with that of field stars and also with the population of wide-separation companions detected in our previous AO survey. We find no evidence that spectroscopic stellar companions are preferentially located in systems with short-period gas giant planets on eccentric and/or misaligned orbits

  11. Distinct Rayleigh scattering from hot spot mutant p53 proteins reveals cancer cells.

    Science.gov (United States)

    Jun, Ho Joon; Nguyen, Anh H; Kim, Yeul Hong; Park, Kyong Hwa; Kim, Doyoun; Kim, Kyeong Kyu; Sim, Sang Jun

    2014-07-23

    The scattering of light redirects and resonances when an electromagnetic wave interacts with electrons orbits in the hot spot core protein and oscillated electron of the gold nanoparticles (AuNP). This report demonstrates convincingly that resonant Rayleigh scattering generated from hot spot mutant p53 proteins is correspondence to cancer cells. Hot spot mutants have unique local electron density changes that affect specificity of DNA binding affinity compared with wild types. Rayleigh scattering changes introduced by hot-spot mutations were monitored by localized surface plasmon resonance (LSPR) shift changes. The LSPR λmax shift for hot-spot mutants ranged from 1.7 to 4.2 nm for mouse samples and from 0.64 nm to 2.66 nm for human samples, compared to 9.6 nm and 15 nm for wild type and mouse and human proteins, respectively with a detection sensitivity of p53 concentration at 17.9 nM. It is interesting that hot-spot mutants, which affect only interaction with DNA, launches affinitive changes as considerable as wild types. These changes propose that hot-spot mutants p53 proteins can be easily detected by local electron density alterations that disturbs the specificity of DNA binding of p53 core domain on the surface of the DNA probed-nanoplasmonic sensor. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Constraining the Mass Loss Geometry of Beta Lyrae

    Directory of Open Access Journals (Sweden)

    Jamie R. Lomax

    2012-03-01

    Full Text Available Massive binary stars lose mass by two mechanisms: jet-driven mass loss during periods of active mass transfer and by wind-driven mass loss. Beta Lyrae is an eclipsing, semi-detached binary whose state of active mass transfer provides a unique opportunity to study how the evolution of binary systems is affected by jet-driven mass loss. Roche lobe overflow from the primary star feeds the thick accretion disk which almost completely obscures the mass-gaining star. A hot spot predicted to be on the edge of the accretion disk may be the source of beta Lyrae’s bipolar outflows. I present results from spectropolarimetric data taken with the University of Wisconsin’s Half-Wave Spectropolarimeter and the Flower and Cook Observatory’s photoelastic modulating polarimeter instrument which have implications for our current understanding of the system’s disk geometry. Using broadband polarimetric analysis, I derive new information about the structure of the disk and the presence and location of a hot spot. These results place constraints on the geometrical distribution of material in beta Lyrae and can help quantify the amount of mass lost from massive interacting binary systems during phases of mass transfer and jet-driven mass loss.

  13. High-precision 2MASS JHK{sub s} light curves and other data for RR Lyrae star SDSS J015450 + 001501: Strong constraints for nonlinear pulsation models

    Energy Technology Data Exchange (ETDEWEB)

    Szabó, Róbert; Ivezić, Željko; Kiss, László L.; Kolláth, Zoltán [Konkoly Observatory, MTA CSFK, Konkoly Thege Miklós út 15-17, H-1121 Budapest (Hungary); Jones, Lynne; Becker, Andrew C.; Davenport, James R. A. [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195-1580 (United States); Sesar, Branimir [Division of Physics, Mathematics and Astronomy, Caltech, Pasadena, CA 91125 (United States); Cutri, Roc M., E-mail: rszabo@konkoly.hu [Infrared Processing and Analysis Center, California Institute of Technology, Pasadena, CA 91125 (United States)

    2014-01-01

    We present and discuss an extensive data set for the non-Blazhko ab-type RR Lyrae star SDSS J015450+001501, including optical Sloan Digital Sky Survey ugriz light curves and spectroscopic data, LINEAR and Catalina Sky Survey unfiltered optical light curves, and infrared Two Micron All Sky Survey (2MASS) JHK{sub s} and Wide-field Infrared Survey Explorer W1 and W2 light curves. Most notable is that light curves obtained by 2MASS include close to 9000 photometric measures collected over 3.3 yr and provide an exceedingly precise view of near-infrared variability. These data demonstrate that static atmosphere models are insufficient to explain multiband photometric light-curve behavior and present strong constraints for nonlinear pulsation models for RR Lyrae stars. It is a challenge to modelers to produce theoretical light curves that can explain data presented here, which we make publicly available.

  14. The hot and cold interstellar matter of early type galaxies and their radio emission

    International Nuclear Information System (INIS)

    Kim, Dongwoo; Fabbiano, G.

    1990-01-01

    Over the last few years, the knowledge of the interstellar matter (ISM) of early type galaxies has increased dramatically. Many early type galaxies are now known to have ISM in three different phases: cold (neutral hydrogen (HI), dust and molecular material), warm (ionized) and hot (S-ray emitting) gas. Early type galaxies have smaller masses of cold ISM (10 to the 7th power - 10 to the 8th power solar mass; Jura et al. 1987) than later type spiral galaxies, while they have far more hot gas (10 to the 9th power - 10 to the tenth power solar mass; Forman et al. 1985, Canizares et al. 1987). In order to understand the relationship between the different phases of the ISM and the role of the ISM in fueling radio continuum sources and star formation, researchers compared observational data from a wide range of wavelengths

  15. Prospects for detection of intermediate-mass black holes in globular clusters using integrated-light spectroscopy

    Science.gov (United States)

    de Vita, R.; Trenti, M.; Bianchini, P.; Askar, A.; Giersz, M.; van de Ven, G.

    2017-06-01

    The detection of intermediate-mass black holes (IMBHs) in Galactic globular clusters (GCs) has so far been controversial. In order to characterize the effectiveness of integrated-light spectroscopy through integral field units, we analyse realistic mock data generated from state-of-the-art Monte Carlo simulations of GCs with a central IMBH, considering different setups and conditions varying IMBH mass, cluster distance and accuracy in determination of the centre. The mock observations are modelled with isotropic Jeans models to assess the success rate in identifying the IMBH presence, which we find to be primarily dependent on IMBH mass. However, even for an IMBH of considerable mass (3 per cent of the total GC mass), the analysis does not yield conclusive results in one out of five cases, because of shot noise due to bright stars close to the IMBH line of sight. This stochastic variability in the modelling outcome grows with decreasing BH mass, with approximately three failures out of four for IMBHs with 0.1 per cent of total GC mass. Finally, we find that our analysis is generally unable to exclude at 68 per cent confidence an IMBH with mass of 103 M⊙ in snapshots without a central BH. Interestingly, our results are not sensitive to GC distance within 5-20 kpc, nor to misidentification of the GC centre by less than 2 arcsec (<20 per cent of the core radius). These findings highlight the value of ground-based integral field spectroscopy for large GC surveys, where systematic failures can be accounted for, but stress the importance of discrete kinematic measurements that are less affected by stochasticity induced by bright stars.

  16. Spectral effects of light-emitting diodes on plant growth and development: The importance of green and blue light

    Science.gov (United States)

    Cope, K. R.; Bugbee, B.

    2011-12-01

    Light-emitting diodes (LEDs) are an emerging technology for plant growth lighting. Due to their narrow spectral output, colored LEDs provide many options for studying the spectral effects of light on plants. Early on, efficient red LEDs were the primary focus of photobiological research; however, subsequent studies have shown that normal plant growth and development cannot be achieved under red light without blue light supplementation. More recent studies have shown that red and blue (RB) LEDs supplemented with green light increase plant dry mass. This is because green light transmits more effectively through the leaf canopy than red and blue light, thus illuminating lower plant leaves and increasing whole-plant photosynthesis. Red, green and blue (RGB) light can be provided by either a conventional white light source (such as fluorescent lights), a combination of RGB LEDs, or from recently developed white LEDs. White LEDs exceed the efficiency of fluorescent lights and have a comparable broad spectrum. As such, they have the potential to replace fluorescent lighting for growth-chamber-based crop production both on Earth and in space. Here we report the results of studies on the effects of three white LED types (warm, neutral and cool) on plant growth and development compared to combinations of RB and RGB LEDs. Plants were grown under two constant light intensities (200 and 500 μmol m-2 s-1). Temperature, environmental conditions and root-zone environment were uniformly maintained across treatments. Phytochrome photoequilbria and red/far-red ratios were similar among treatments and were comparable to conventional fluorescent lights. Blue light had a significant effect on both plant growth (dry mass gain) and development (dry mass partitioning). An increase in the absolute amount (μmol m-2 s-1) of blue light from 0-80 μmol m-2 s-1 resulted in a decrease in stem elongation, independent of the light intensity. However, an increase in the relative amount (%) of blue

  17. Phase shifts and nonellipsoidal light curves: Challenges from mass determinations in x-ray binary stars

    Science.gov (United States)

    Cantrell, Andrew Glenn

    We consider two types of anomalous observations which have arisen from efforts to measure dynamical masses of X-ray binary stars: (1) Radial velocity curves which seemingly show the primary and the secondary out of antiphase in most systems, and (2) The observation of double-waved light curves which deviate significantly from the ellipsoidal modulations expected for a Roche lobe filling star. We consider both problems with the joint goals of understanding the physical origins of the anomalous observations, and using this understanding to allow robust dynamical determinations of mass in X-ray binary systems. In our analysis of phase-shifted radial velocity curves, we discuss a comprehensive sample of X-ray binaries with published phase-shifted radial velocity curves. We show that the most commonly adopted explanation for phase shifts is contradicted by many observations, and consider instead a generalized form of a model proposed by Smak in 1970. We show that this model is well supported by a range of observations, including some systems which had previously been considered anomalous. We lay the groundwork for the derivation of mass ratios based on our explanation for phase shifts, and we discuss the work necessary to produce more detailed physical models of the phase shift. In our analysis of non-ellipsoidal light curves, we focus on the very well-studied system A0620-00. We present new VIH SMARTS photometry spanning 1999-2007, and supplement this with a comprehensive collection of archival data obtained since 1981. We show that A0620-00 undergoes optical state changes within X-ray quiescence and argue that not all quiescent data should be used for determinations of the inclination. We identify twelve light curves which may reliably be used for determining the inclination. We show that the accretion disk contributes significantly to all twelve curves and is the dominant source of nonellipsoidal variations. We derive the disk fraction for each of the twelve curves

  18. Light hadrons from lattice QCD with light (u,d), strange and charm dynamical quarks

    International Nuclear Information System (INIS)

    Baron, R.

    2010-04-01

    We present results of lattice QCD simulations with mass-degenerate up and down and mass-split strange and charm (N f =2+1+1) dynamical quarks using Wilson twisted mass fermions at maximal twist. The tuning of the strange and charm quark masses is performed at two values of the lattice spacing a ∼ 0:078 fm and a ∼0.086 fm with lattice sizes ranging from L∼1.9 fm to L∼2.8 fm. We measure with high statistical precision the light pseudoscalar mass m PS and decay constant f PS in a range 270 PS 0 and anti l 3,4 of SU(2) chiral perturbation theory. We use the two values of the lattice spacing, several lattice sizes as well as different values of the light, strange and charm quark masses to explore the systematic effects. A first study of discretisation effects in light-quark observables and a comparison to N f =2 results are performed. (orig.)

  19. Silicon nanowire hot carrier electroluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Plessis, M. du, E-mail: monuko@up.ac.za; Joubert, T.-H.

    2016-08-31

    Avalanche electroluminescence from silicon pn junctions has been known for many years. However, the internal quantum efficiencies of these devices are quite low due to the indirect band gap nature of the semiconductor material. In this study we have used reach-through biasing and SOI (silicon-on-insulator) thin film structures to improve the internal power efficiency and the external light extraction efficiency. Both continuous silicon thin film pn junctions and parallel nanowire pn junctions were manufactured using a custom SOI technology. The pn junctions are operated in the reach-through mode of operation, thus increasing the average electric field within the fully depleted region. Experimental results of the emission spectrum indicate that the most dominant photon generating mechanism is due to intraband hot carrier relaxation processes. It was found that the SOI nanowire light source external power efficiency is at least an order of magnitude better than the comparable bulk CMOS (Complementary Metal Oxide Semiconductor) light source. - Highlights: • We investigate effect of electric field on silicon avalanche electroluminescence. • With reach-through pn junctions the current and carrier densities are kept constant. • Higher electric fields increase short wavelength radiation. • Higher electric fields decrease long wavelength radiation. • The effect of the electric field indicates intraband transitions as main mechanism.

  20. Non-Metallic Inclusions and Hot-Working Behaviour of Advanced High-Strength Medium-Mn Steels

    Directory of Open Access Journals (Sweden)

    Grajcar A.

    2016-06-01

    Full Text Available The work addresses the production of medium-Mn steels with an increased Al content. The special attention is focused on the identification of non-metallic inclusions and their modification using rare earth elements. The conditions of the thermomechanical treatment using the metallurgical Gleeble simulator and the semi-industrial hot rolling line were designed for steels containing 3 and 5% Mn. Hot-working conditions and controlled cooling strategies with the isothermal holding of steel at 400°C were selected. The effect of Mn content on the hot-working behaviour and microstructure of steel was addressed. The force-energetic parameters of hot rolling were determined. The identification of structural constituents was performed using light microscopy and scanning electron microscopy methods. The addition of rare earth elements led to the total modification of non-metallic inclusions, i.e., they replaced Mn and Al forming complex oxysulphides. The Mn content in a range between 3 and 5% does not affect the inclusion type and the hot-working behaviour. In contrast, it was found that Mn has a significant effect on a microstructure.

  1. Hot wire radicals and reactions

    International Nuclear Information System (INIS)

    Zheng Wengang; Gallagher, Alan

    2006-01-01

    Threshold ionization mass spectroscopy is used to measure radical (and stable gas) densities at the substrate of a tungsten hot wire (HW) reactor. We report measurements of the silane reaction probability on the HW and the probability of Si and H release from the HW. We describe a model for the atomic H release, based on the H 2 dissociation model. We note major variations in silicon-release, with dependence on prior silane exposure. Measured radical densities versus silane pressure yield silicon-silane and H-silane reaction rate coefficients, and the dominant radical fluxes to the substrate

  2. Direct mass measurements in the light neutron-rich region using a combined energy and time-of-flight technique

    International Nuclear Information System (INIS)

    Pillai, C.; Swenson, L.W.; Vieira, D.J.; Butler, G.W.; Wouters, J.M.; Rokni, S.H.; Vaziri, K.; Remsberg, L.P.

    1985-01-01

    This experiment has demonstrated that direct mass measurements can be performed (albeit of low precision in this first attempt) using the M proportional to ET 2 method. This technique has the advantage that many particle-bound nuclei, produced in fragmentation reactions can be measured simultaneously, independent of their N or Z. The main disadvantage of this approach is that both energy and time-of-flight must be measured precisely on an absolute scale. Although some mass walk with N and Z was observed in this experiment, these uncertainties were largely removed by extrapolating the smooth dependence observed for known nuclei which lie closer to the valley of β-stability. Mass measurements for several neutron-rich light nuclei ranging from 17 C to 26 Ne have been performed. In all cases these measurements agree with the latest mass compilation of Wapstra and Audi. The masses of 20 N and 24 F have been determined for the first time

  3. Leptogenesis and neutrino masses

    International Nuclear Information System (INIS)

    Pluemacher, M.

    2004-01-01

    Thermal leptogenesis explains the baryon asymmetry of the universe by the out-of-equilibrium decays of heavy right-handed neutrinos. In the minimal seesaw model this leads to interesting implications for light neutrino properties. In particular, quasi-degenerate light neutrino masses are incompatible with leptogenesis. An upper bound on light neutrino masses of 0.1 eV can be derived, which will be tested by forthcoming laboratory experiments and cosmology. (author)

  4. Case study. Health hazards of automotive repair mechanics: thermal and lighting comfort, particulate matter and noise.

    Science.gov (United States)

    Loupa, G

    2013-01-01

    An indoor environmental quality survey was conducted in a small private automotive repair shop during May 2009 (hot season) and February 2010 (cold season). It was established that the detached building, which is naturally ventilated and lit, had all the advantages of the temperate local climate. It provided a satisfactory microclimatic working environment, concerning the thermal and the lighting comfort, without excessive energy consumption for air-conditioning or lighting. Indoor number concentrations of particulate matter (PM) were monitored during both seasons. Their size distributions were strongly affected by the indoor activities and the air exchange rate of the building. During working hours, the average indoor/outdoor (I/O) number concentration ratio was 31 for PM0.3-1 in the hot season and 69 for the cold season. However I/O PM1-10 number concentration ratios were similar, 33 and 32 respectively, between the two seasons. The estimated indoor mass concentration of PM10 for the two seasons was on average 0.68 mg m(-3) and 1.19 mg m(-3), i.e., 22 and 36 times higher than outdoors, during the hot and the cold seasons, respectively. This is indicative that indoor air pollution may adversely affect mechanics' health. Noise levels were highly variable and the average LEX, 8 h of 69.3 dB(A) was below the European Union exposure limit value 87db (A). Noise originated from the use of manual hammers, the revving up of engines, and the closing of car doors or hoods. Octave band analysis indicated that the prevailing noise frequencies were in the area of the maximum ear sensitivity.

  5. THE HOT INTERSTELLAR MEDIUM OF THE INTERACTING GALAXY NGC 4490

    International Nuclear Information System (INIS)

    Richings, A. J.; Fabbiano, G.; Wang Junfeng; Roberts, T. P.

    2010-01-01

    We present an analysis of the hot interstellar medium (ISM) in the spiral galaxy NGC 4490, which is interacting with the irregular galaxy NGC 4485, using ∼100 ks of Chandra ACIS-S observations. The high angular resolution of Chandra enables us to remove discrete sources and perform spatially resolved spectroscopy for the star-forming regions and associated outflows, allowing us to look at how the physical properties of the hot ISM such as temperature, hydrogen column density, and metal abundances vary throughout these galaxies. We find temperatures of >0.41 keV and 0.85 +0.59 -0.12 keV, electron densities of >1.87η -1/2 x 10 -3 cm -3 and 0.21 +0.03 -0.04 η -1/2 x 10 -3 cm -3 , and hot gas masses of >1.1η 1/2 x 10 7 M sun and ∼3.7η 1/2 x 10 7 M sun in the plane and halo of NGC 4490, respectively, where η is the filling factor of the hot gas. The abundance ratios of Ne, Mg, and Si with respect to Fe are found to be consistent with those predicted by theoretical models of type II supernovae (SNe). The thermal energy in the hot ISM is ∼5% of the total mechanical energy input from SNe, so it is likely that the hot ISM has been enriched and heated by type II SNe. The X-ray emission is anticorrelated with the Hα and mid-infrared emission, suggesting that the hot gas is bounded by filaments of cooler ionized hydrogen mixed with warm dust.

  6. Capability and opportunity in hot shooting performance: Evidence from top-scoring NBA leaders

    Science.gov (United States)

    2018-01-01

    In basketball games, whenever players successfully shoot in streaks, they are expected to demonstrate heightened performance for a stretch of time. Streak shooting in basketball has been debated for more than three decades, but most studies have provided little significant statistical evidence and have labeled random subjective judgments the “hot hand fallacy.” To obtain a broader perspective of the hot hand phenomenon and its accompanying influences on the court, this study uses field goal records and optical tracking data from the official NBA database for the entire 2015–2016 season to analyze top-scoring leaders’ shooting performances. We first reflect on the meaning of “hot hand” and the “Matthew effect” in actual basketball competition. Second, this study employs statistical models to integrate three different shooting perspectives (field goal percentage, points scored, and attempts). This study’s findings shed new light not only on the existence or nonexistence of streaks, but on the roles of capability and opportunity in NBA hot shooting. Furthermore, we show how hot shooting performances resulting from capability and opportunity lead to actual differences for teams. PMID:29432458

  7. Partial Replacement of Cement with Bagasse Ash in Hot Mix Asphalt ...

    African Journals Online (AJOL)

    It is in this light that a laboratory based investigation for the replacement of cement with BA in Hot Mix Asphalt (HMA) was conducted. Tests on the suitability of materials used and their performance in terms of known engineering properties was carried out. Bitumen content of 4.5%, 5.5%, 6.5% and 7.5% was adopted.

  8. Hot rolling of thick uranium molybdenum alloys

    Science.gov (United States)

    DeMint, Amy L.; Gooch, Jack G.

    2015-11-17

    Disclosed herein are processes for hot rolling billets of uranium that have been alloyed with about ten weight percent molybdenum to produce cold-rollable sheets that are about one hundred mils thick. In certain embodiments, the billets have a thickness of about 7/8 inch or greater. Disclosed processes typically involve a rolling schedule that includes a light rolling pass and at least one medium rolling pass. Processes may also include reheating the rolling stock and using one or more heavy rolling passes, and may include an annealing step.

  9. Liquid phase hot atom chemistry: At crossroads

    International Nuclear Information System (INIS)

    Rack, E.P.; Veterans Administration Medical Center, Omaha, NE

    1981-01-01

    The state of current research in liquid phase hot atom chemistry is discussed. Four classes of experimental approaches are high-lighted. These include 1) primary physical data for (n,γ)-activated 128 I, (I.T.)-activated 130 I and effects on chemical reactivity; 2) the density-variation technique involving iodine reactions with saturated and unsaturated hydrocarbons; 3) stereochemistry experiments on chlorocarbon molecules with single and multiple chiral centers; and 4) experiments employing dilute aqueous solutions of halogenerated biomolecules in the ice state, exposed to neutron irradiation. (orig.) [de

  10. Application of the mass-spectrometer MASHA for mass-spectrometry and laser-spectroscopy

    Science.gov (United States)

    Rodin, A. M.; Belozerov, A. V.; Dmitriev, S. N.; Oganessian, Yu. Ts.; Sagaidak, R. N.; Salamatin, V. S.; Stepantsov, S. V.; Vanin, D. V.

    2010-02-01

    We report the present status of the mass-spectrometer MASHA (Mass-Analyzer of Supper Heavy Atoms) designed for determination of the masses of superheavy elements. The mass-spectrometer is connected to the U-400M cyclotron of the Flerov Laboratory for Nuclear Reactions (FLNR) JINR, Dubna. The first experiments on mass-measurements for 112 and 114 elements will be performed in the upcoming 2010. For this purpose a hot catcher, based on a graphite stopper, is constructed. The α-decay of the superheavy nuclides or spontaneous fission products will be detected with a silicon 192 strips detector. The experimental program of future investigations using the technique of a gas catcher is discussed. It should be regarded as an alternative of the classical ISOL technique. The possibilities are considered for using this mass-spectrometer for laser spectroscopy of nuclei far off-stability.

  11. Application of the mass-spectrometer MASHA for mass-spectrometry and laser-spectroscopy

    International Nuclear Information System (INIS)

    Rodin, A. M.; Belozerov, A. V.; Dmitriev, S. N.; Oganessian, Yu. Ts.; Sagaidak, R. N.; Salamatin, V. S.; Stepantsov, S. V.; Vanin, D. V.

    2010-01-01

    We report the present status of the mass-spectrometer MASHA (Mass-Analyzer of Supper Heavy Atoms) designed for determination of the masses of superheavy elements. The mass-spectrometer is connected to the U-400M cyclotron of the Flerov Laboratory for Nuclear Reactions (FLNR) JINR, Dubna. The first experiments on mass-measurements for 112 and 114 elements will be performed in the upcoming 2010. For this purpose a hot catcher, based on a graphite stopper, is constructed. The α-decay of the superheavy nuclides or spontaneous fission products will be detected with a silicon 192 strips detector. The experimental program of future investigations using the technique of a gas catcher is discussed. It should be regarded as an alternative of the classical ISOL technique. The possibilities are considered for using this mass-spectrometer for laser spectroscopy of nuclei far off-stability.

  12. Application of the mass-spectrometer MASHA for mass-spectrometry and laser-spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Rodin, A. M., E-mail: rodin@nrmail.jinr.ru; Belozerov, A. V.; Dmitriev, S. N.; Oganessian, Yu. Ts.; Sagaidak, R. N.; Salamatin, V. S.; Stepantsov, S. V.; Vanin, D. V. [JINR, Flerov Laboratory of Nuclear Reactions (Russian Federation)

    2010-02-15

    We report the present status of the mass-spectrometer MASHA (Mass-Analyzer of Supper Heavy Atoms) designed for determination of the masses of superheavy elements. The mass-spectrometer is connected to the U-400M cyclotron of the Flerov Laboratory for Nuclear Reactions (FLNR) JINR, Dubna. The first experiments on mass-measurements for 112 and 114 elements will be performed in the upcoming 2010. For this purpose a hot catcher, based on a graphite stopper, is constructed. The {alpha}-decay of the superheavy nuclides or spontaneous fission products will be detected with a silicon 192 strips detector. The experimental program of future investigations using the technique of a gas catcher is discussed. It should be regarded as an alternative of the classical ISOL technique. The possibilities are considered for using this mass-spectrometer for laser spectroscopy of nuclei far off-stability.

  13. Measuring and engineering the atomic mass density wave of a Gaussian mass-polariton pulse in optical fibers

    Science.gov (United States)

    Partanen, Mikko; Tulkki, Jukka

    2018-02-01

    Conventional theories of electromagnetic waves in a medium assume that only the energy of the field propagates inside the medium. Consequently, they neglect the transport of mass density by the medium atoms. We have recently presented foundations of a covariant theory of light propagation in a nondispersive medium by considering a light wave simultaneously with the dynamics of the medium atoms driven by optoelastic forces [Phys. Rev. A 95, 063850 (2017)]. In particular, we have shown that the mass is transferred by an atomic mass density wave (MDW), which gives rise to mass-polariton (MP) quasiparticles, i.e., covariant coupled states of the field and matter having a nonzero rest mass. Another key observation of the mass-polariton theory of light is that, in common semiconductors, most of the momentum of light is transferred by moving atoms, e.g., 92% in the case of silicon. In this work, we generalize the MP theory of light for dispersive media and consider experimental measurement of the mass transferred by the MDW atoms when an intense light pulse propagates in a silicon fiber. In particular, we consider optimal intensity and time dependence of a Gaussian pulse and account for the breakdown threshold irradiance of the material. The optical shock wave property of the MDW, which propagates with the velocity of light instead of the velocity of sound, prompts for engineering of novel device concepts like very high frequency mechanical oscillators not limited by the acoustic cutoff frequency.

  14. Light-by-Light Scattering Constraint on Born-Infeld Theory.

    Science.gov (United States)

    Ellis, John; Mavromatos, Nick E; You, Tevong

    2017-06-30

    The recent measurement by ATLAS of light-by-light scattering in LHC Pb-Pb collisions is the first direct evidence for this basic process. We find that it excludes a range of the mass scale of a nonlinear Born-Infeld extension of QED that is ≲100  GeV, a much stronger constraint than those derived previously. In the case of a Born-Infeld extension of the standard model in which the U(1)_{Y} hypercharge gauge symmetry is realized nonlinearly, the limit on the corresponding mass reach is ∼90  GeV, which, in turn, imposes a lower limit of ≳11  TeV on the magnetic monopole mass in such a U(1)_{Y} Born-Infeld theory.

  15. Hot-start Giant Planets Form with Radiative Interiors

    Energy Technology Data Exchange (ETDEWEB)

    Berardo, David; Cumming, Andrew, E-mail: david.berardo@mcgill.ca, E-mail: andrew.cumming@mcgill.ca [Department of Physics and McGill Space Institute, McGill University, 3600 rue University, Montreal, QC H3A 2T8 (Canada)

    2017-09-10

    In the hot-start core accretion formation model for gas giants, the interior of a planet is usually assumed to be fully convective. By calculating the detailed internal evolution of a planet assuming hot-start outer boundary conditions, we show that such a planet will in fact form with a radially increasing internal entropy profile, so that its interior will be radiative instead of convective. For a hot outer boundary, there is a minimum value for the entropy of the internal adiabat S {sub min} below which the accreting envelope does not match smoothly onto the interior, but instead deposits high entropy material onto the growing interior. One implication of this would be to at least temporarily halt the mixing of heavy elements within the planet, which are deposited by planetesimals accreted during formation. The compositional gradient this would impose could subsequently disrupt convection during post-accretion cooling, which would alter the observed cooling curve of the planet. However, even with a homogeneous composition, for which convection develops as the planet cools, the difference in cooling timescale will change the inferred mass of directly imaged gas giants.

  16. Thermal multifragmentation of hot nuclei and liquid-fog phase transition

    International Nuclear Information System (INIS)

    Karnaukhov, V.A.; Avdeev, S.P.; Duginova, E.V.

    2002-01-01

    Multiple emission of intermediate-mass fragments in the collisions of protons (up to 8.1 GeV), 4 He(4 and 14.6GeV) and 12 C(22.4 GeV) on Au has been studied with the 4π-setup FASA. In all cases thermal multifragmentation of the hot and diluted target spectator takes place. The fragment multiplicity and charge distributions are well described by the combined model including the modified intranuclear cascade followed by the statistical multibody decay of the hot system. IMF-IMF correlation study supports this picture giving very short time scale of the process (τ≤70fm/c). This decay process can be interpreted as the first order nuclear liquid-fog phase transition inside the spinodal region. The evolution of the mechanism of thermal multifragmentation with increasing projectile mass was investigated. The onset of the radial collective flow was observed for heavier projectiles. The analysis reveals the information on the fragment space distribution inside the break-up volume: heavier IMF are formed predominantly in the interior of the fragmenting nucleus possibly due to the density gradient

  17. Thermal Multifragmentation of Hot Nuclei and Liquid-Fog Phase Transition

    CERN Document Server

    Karnaukhov, V A; Duginova, E V; Petrov, L A; Rodionov, V K; Oeschler, H; Budzanowski, A; Karcz, W; Janicki, M; Bochkarev, O V; Kuzmin, E A; Chulkov, L V; Norbeck, E; Botvina, A S

    2002-01-01

    Multiple emission of intermediate-mass fragments in the collisions of protons (up to 8.1 GeV), ^{4}He (4 and 14.6 GeV) and ^{12}C (22.4 GeV) on Au has been studied with the 4\\pi-setup FASA. In all cases thermal multifragmentation of the hot and diluted target spectator takes place. The fragment multiplicity and charge distributions are well described by the combined model including the modified intranuclear cascade followed by the statistical multibody decay of the hot system. IMF-IMF correlation study supports this picture giving very short time scale of the process (\\tau\\le 70 fm/c). This decay process can be interpreted as the first order nuclear liquid-fog phase transition inside the spinodal region. The evolution of the mechanism of thermal multifragmentation with increasing projectile mass was investigated. The onset of the radial collective flow was observed for heavier projectiles. The analysis reveals the information on the fragment space distribution ins! ide the break-up volume: heavier IMF are for...

  18. The ATLAS(3D) project : XIX. The hot gas content of early-type galaxies: fast versus slow rotators

    NARCIS (Netherlands)

    Sarzi, Marc; Alatalo, Katherine; Blitz, Leo; Bois, Maxime; Bournaud, Frederic; Bureau, Martin; Cappellari, Michele; Crocker, Alison; Davies, Roger L.; Davis, Timothy A.; de Zeeuw, P. T.; Duc, Pierre-Alain; Emsellem, Eric; Khochfar, Sadegh; Krajnovic, Davor; Kuntschner, Harald; Lablanche, Pierre-Yves; McDermid, Richard M.; Morganti, Raffaella; Naab, Thorsten; Oosterloo, Tom; Scott, Nicholas; Serra, Paolo; Young, Lisa M.; Weijmans, Anne-Marie

    2013-01-01

    For early-type galaxies, the ability to sustain a corona of hot, X-ray-emitting gas could have played a key role in quenching their star formation history. A halo of hot gas may act as an effective shield against the acquisition of cold gas and can quickly absorb stellar mass loss material. Yet,

  19. The ATLAS3D project - XIX. The hot gas content of early-type galaxies: fast versus slow rotators

    NARCIS (Netherlands)

    Sarzi, Marc; Alatalo, Katherine; Blitz, Leo; Bois, Maxime; Bournaud, Frédéric; Bureau, Martin; Cappellari, Michele; Crocker, Alison; Davies, Roger L.; Davis, Timothy A.; de Zeeuw, P. T.; Duc, Pierre-Alain; Emsellem, Eric; Khochfar, Sadegh; Krajnović, Davor; Kuntschner, Harald; Lablanche, Pierre-Yves; McDermid, Richard M.; Morganti, Raffaella; Naab, Thorsten; Oosterloo, Tom; Scott, Nicholas; Serra, Paolo; Young, Lisa M.; Weijmans, Anne-Marie

    For early-type galaxies, the ability to sustain a corona of hot, X-ray-emitting gas could have played a key role in quenching their star formation history. A halo of hot gas may act as an effective shield against the acquisition of cold gas and can quickly absorb stellar mass loss material. Yet,

  20. Application of Hot-wire Method for Measuring Thermal Conductivity of Fine Ceramics

    Directory of Open Access Journals (Sweden)

    Shangxi WANG

    2016-11-01

    Full Text Available Ceramic substrate is preferred in high density packaging due to its high electrical resistivity and moderate expansion coefficient. The thermal conductivity is a key parameter for packaging substrates. There are two common methods to measure the thermal conductivity, which are the hot-wire method and the laser-flash method. Usually, the thermal conductivities of porcelain is low and meet the measurement range of hot-wire method, and the measured value by hot-wire method has little difference with that by laser-flash method. In recent years, with the requirement of high-powered LED lighting, some kinds of ceramic substrates with good thermal conductivity have been developed and their thermal conductivity always measured by the means of laser flash method, which needs expensive instrument. In this paper, in order to detect the thermal conductivity of fine ceramic with convenience and low cost, the feasibility of replacing the laser flash method with hot wire method to measure thermal conductivity of ceramic composites was studied. The experiment results showed that the thermal conductivity value of fine ceramics measured by the hot-wire method is severely lower than that by the laser-flash method. However, there is a positive relationship between them. It is possible to measure the thermal conductivity of fine ceramic workpiece instantly by hot-wire method via a correction formula.DOI: http://dx.doi.org/10.5755/j01.ms.22.4.12543

  1. Current status of JAERI Tokai hot cell facilities

    International Nuclear Information System (INIS)

    Itami, Hiroharu; Morozumi, Minoru; Yamahara, Takeshi

    1992-01-01

    JAERI has 4 hot cell facilities in order to examine high radioactive materials. Three of them, the Research Hot Laboratory, the Reactor Fuel Examination Facility and the Waste Safety Testing Facility are located in the JAERI Tokai site, and the rest is the JMTR Hot Laboratory in the Oarai site. The Research Hot Laboratory (RHL) was constructed for post-irradiation examination (PIE), especially nuclear related basic research experiment, such as metallurgical, chemical and mechanical examination on fuels and materials irradiated in research and test reactors. This facility has 10 large dimension concrete and 38 lead cells. At present the RHL is used for various kinds of examinations of high radioactive samples such as fuels of research and test reactors, power reactors and high temperature testing reactor (HTTR), and structural materials. The Reactor Fuel Examination Facility (RFEF) was designed and constructed for carrying out PIE of irradiated full-size fuel assemblies of light water reactors (LWRs). This facility has a storage pool, 8 concrete and 5 lead cells. They are currently used for safety evaluation on high burnup and advanced lWR fuels as part of the national program. The Waste Safety Testing Facility (WASTEF) was designed and constructed for safety research on long-term storage and disposal of high level radioactive wastes, generated by fuel reprocessing. The WASTEF has 5 concrete cells and 1 lead cell. Examinations on the behavior of various long-lived fission products in a glass form and in a canister and, releasing behavior of them out of a canister are carrying out under the condition at storage. (author)

  2. POPULATION SYNTHESIS OF HOT SUBDWARFS: A PARAMETER STUDY

    International Nuclear Information System (INIS)

    Clausen, Drew; Wade, Richard A.; Kopparapu, Ravi Kumar; O'Shaughnessy, Richard

    2012-01-01

    Binaries that contain a hot subdwarf (sdB) star and a main-sequence companion may have interacted in the past. This binary population has historically helped determine our understanding of binary stellar evolution. We have computed a grid of binary population synthesis models using different assumptions about the minimum core mass for helium ignition, the envelope binding energy, the common-envelope ejection efficiency, the amount of mass and angular momentum lost during stable mass transfer, and the criteria for stable mass transfer on the red giant branch and in the Hertzsprung gap. These parameters separately and together can significantly change the entire predicted population of sdBs. Nonetheless, several different parameter sets can reproduce the observed subpopulation of sdB + white dwarf and sdB + M dwarf binaries, which has been used to constrain these parameters in previous studies. The period distribution of sdB + early F dwarf binaries offers a better test of different mass transfer scenarios for stars that fill their Roche lobes on the red giant branch.

  3. Theoretical study of hydraulic jump during circular horizontal hot leg injection in pressurized water reactor

    International Nuclear Information System (INIS)

    El Hawary, Shehab; Abu-Elyazeed, Osayed S.M.; Fahmy, Adel Alyan; Meglaa, Khairy

    2016-01-01

    Highlights: • The model is developed to predict the occurrence of onset hydraulic jump in a circular pipe. • Theoretical results are in agreement with experimental results and theory. • Effects of diameter of the injection pipe, Froude number and injected coolant mass are studied. - Abstract: One important phenomenon occurring during Loss of Coolant Accident (LOCA) is Counter-Current Flow Limitation (CCFL). The incidence of such CCFL is introduced by the onset of hydraulic jump. In the present work, a one dimensional model was modified to fit circular hot channel. The model was used to study the factors affecting the initial Froude number, the location of the occurrence of the hydraulic jump, and the critical coolant flow depth during circular horizontal hot leg injection in US-APWR Mitsubishi Reactor. The results showed good agreement with published experimental data of the Upper Plenum Test Facility (UPTF) at Mannheim, Germany. It was found that higher injected coolant mass flow rate increases the initial Froude number, the location of the occurrence of the hydraulic jump, and the critical injection depth divided by the diameter of the injection pipe. Such behavior is thought to be due to the increase of the inertia force by increasing of the injected coolant mass flow rate and the inverse of the diameter of the injection pipe. It was found also that, the location of the occurrence of hydraulic jump increases with decreasing load effect. Therefore, these results reveal that the avoidance of CCFL as well as hydraulic jump through hot leg at maximum load can be achieved by decreasing the distance between the injection point and the pressure vessel to below 0.3 m, and with diameter of 4 in (10.16 cm) as the design diameter of the injection pipe in US-APWR Mitsubishi Reactor. Moreover, the maximum critical depth (56 cm) is less than the diameter of the hot leg (78.74 cm) at an injected coolant mass flow of 400 kg/s, and with diameter of 4 in (10.16 cm) as the

  4. Assessing Light Pollution in China Based on Nighttime Light Imagery

    Directory of Open Access Journals (Sweden)

    Wei Jiang

    2017-02-01

    Full Text Available Rapid urbanization and economic development inevitably lead to light pollution, which has become a universal environmental issue. In order to reveal the spatiotemporal patterns and evolvement rules of light pollution in China, images from 1992 to 2012 were selected from the Defense Meteorological Satellite Program Operational Linescan System (DMSP/OLS and systematically corrected to ensure consistency. Furthermore, we employed a linear regression trend method and nighttime light index method to demonstrate China’s light pollution characteristics across national, regional, and provincial scales, respectively. We found that: (1 China’s light pollution expanded significantly in provincial capital cities over the past 21 years and hot-spots of light pollution were located in the eastern coastal region. The Yangtze River Delta, Pearl River Delta, and Beijing–Tianjin–Hebei regions have formed light pollution stretch areas; (2 China’s light pollution was mainly focused in areas of north China (NC and east China (EC, which, together, accounted for over 50% of the light pollution for the whole country. The fastest growth of light pollution was observed in northwest China (NWC, followed by southwest China (SWC. The growth rates of east China (EC, central China (CC, and northeast China (NEC were stable, while those of north China (NC and south China (SC declined; (3 Light pollution at the provincial scale was mainly located in the Shandong, Guangdong, and Hebei provinces, whereas the fastest growth of light pollution was in Tibet and Hainan. However, light pollution levels in the developed provinces (Hong Kong, Macao, Shanghai, and Tianjin were higher than those of the undeveloped provinces. Similarly, the light pollution heterogeneities of Taiwan, Beijing, and Shanghai were higher than those of undeveloped western provinces.

  5. Formation of Neutral Disk-Like Zone Around the Active Hot Stars in Symbiotic Binaries

    Directory of Open Access Journals (Sweden)

    Cariková Z.

    2012-06-01

    Full Text Available In this contribution we present the ionization structure in the enhanced wind from the hot star in symbiotic binaries during active phases. Rotation of the hot star leads to the compression of the outflowing material towards its equatorial plane. As a result, a neutral disk-like zone around the active hot star near the orbital plane is created. We modeled the compression of the wind and calculated the neutral disk-like zone in the enhanced wind from the hot star using the equation of the photoionization equilibrium. the presence of such neutral disk-like zones was also suggested on the basis of the modeling the spectral energy distribution of symbiotic binaries. We confront the calculated ionization structures in the enhanced wind from the hot star with the observations. the calculated column density of the neutral hydrogen atoms in the neutral disk-like zone and the emission measure of the ionized part of the wind from the hot star are in a good agreement with the quantities derived from observations during active phases. the presence of such neutral disk-like zones is transient, being connected with the active phases of symbiotic binaries. During quiescent phases, such neutral disk-like zones cannot be created because of insufficient mass-loss rate from the hot star.

  6. Composition-dependent hot carrier relaxation dynamics in cesium lead halide (CsPbX{sub 3}, X=Br and I) perovskite nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Heejae; Jung, Seok Il; Kim, Hyo Jin; Cha, Wonhee; Sim, Eunji; Kim, Dongho [Department of Chemistry, Yonsei University, Seoul (Korea, Republic of); Koh, Weon-Kyu [Device Laboratory, Samsung Advanced Institute of Technology, Suwon (Korea, Republic of); Kim, Jiwon [School of Integrated Technology and Underwood International College, Yonsei University, Incheon (Korea, Republic of)

    2017-04-03

    Cesium-based perovskite nanocrystals (NCs) have outstanding photophysical properties improving the performances of lighting devices. Fundamental studies on excitonic properties and hot-carrier dynamics in perovskite NCs further suggest that these materials show higher efficiencies compared to the bulk form of perovskites. However, the relaxation rates and pathways of hot-carriers are still being elucidated. By using ultrafast transient spectroscopy and calculating electronic band structures, we investigated the dependence of halide in Cs-based perovskite (CsPbX{sub 3} with X=Br, I, or their mixtures) NCs on the hot-carrier relaxation processes. All samples exhibit ultrafast (<0.6 ps) hot-carrier relaxation dynamics with following order: CsPbBr{sub 3} (310 fs)>CsPbBr{sub 1.5}I{sub 1.5} (380 fs)>CsPbI{sub 3} NC (580 fs). These result accounts for a reduced light emission efficiency of CsPbI{sub 3} NC compared to CsPbBr{sub 3} NC. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Hot Accretion onto Black Holes with Outflow

    Directory of Open Access Journals (Sweden)

    Park Myeong-Gu

    2018-01-01

    Full Text Available Classic Bondi accretion flow can be generalized to rotating viscous accretion flow. Study of hot accretion flow onto black holes show that its physical charateristics change from Bondi-like for small gas angular momentum to disk-like for Keperian gas angular momentum. Especially, the mass accretion rate divided by the Bondi accretion rate is proportional to the viscosity parameter alpha and inversely proportional to the gas angular momentum divided by the Keplerian angular momentum at the Bondi radius for gas angular momentum comparable to the Keplerian value. The possible presence of outflow will increase the mass inflow rate at the Bondi radius but decrease the mass accretion rate across the black hole horizon by many orders of magnitude. This implies that the growth history of supermassive black holes and their coevolution with host galaxies will be dramatically changed when the accreted gas has angular momentum or develops an outflow.

  8. Experimental Investigation of the Hot Water Layer Effect on Upward Flow Open Pool Reactor Operability

    International Nuclear Information System (INIS)

    Abou Elmaaty, T.

    2014-01-01

    The open pool reactor offers a high degree of reliability in the handling and manoeuvring, the replacement of reactor internal components and the suing of vertical irradiation channels. The protection of both the operators and the reactor hall environment against radiation hazards is considered a matter of interest. So, a hot water layer is implemented above many of the research reactors main pool, especially those whose flow direction is upward flow. An experimental work was carried out to ensure the operability of the upward flow open pool research reactor with / without the hot water layer. The performed experiment showed that, the hot water layer is produced an inverse buoyant force make the water to diffuse downward against the ordinary natural circulation from the reactor core. An upward flow - open pool research reactor (with a power greater than 20 M watt) could not wok without a hot water layer. The high temperature of the hot water layer surface could release a considerable amount of water vapour into the reactor hall, so a heat and mass transfer model is built based on the measured hot water layer surface temperature to calculate the amount of released water vapour during the reactor operating period. The effects of many parameters like the ambient air temperature, the reactor hall relative humidity and the speed of the pushed air layer above the top pool end on the evaporation rate is studied. The current study showed that, the hot water layer system is considered an efficient shielding system against Gamma radiation for open pool upward flow reactor and that system should be operated before the reactor start up by a suitable period of time. While, the heat and mass transfer model results showed that, the amount of the released water vapour is increased as a result of both the increase in hot water layer surface temperature and the increase in air layer speed. As the increase in hot water layer surface temperature could produce a good operability

  9. Experimental Investigation of the Hot Water Layer Effect on Upward Flow Open Pool Reactor Operability

    International Nuclear Information System (INIS)

    Abou Elmaaty, T.

    2015-01-01

    The open pool reactor offers a high degree of reliability in the handling and manoeuvring, the replacement of reactor internal components and the swing of vertical irradiation channels. The protection of both the operators and the reactor hall environment against radiation hazards is considered a matter of interest. So, a hot water layer implemented above many of the research reactors main pool, especially those whose flow direction is upward flow. An experimental work was carried out to ensure the operability of the upward flow open pool research reactor with / without the hot water layer. The performed experiment showed that, the hot water layer produced an inverse buoyant force making the water to diffuse downward against the ordinary natural circulation from the reactor core. An upward flow-open pool research reactor (with a power greater than 20 Mw) could not wok without a hot water layer. The high temperature of the hot water layer surface could release a considerable amount of water vapour into the reactor hall, so a heat and mass transfer model is built based on the measured hot water layer surface temperature to calculate the amount of released water vapour during the reactor operating period. The effects of many parameters like the ambient air temperature, the reactor hall relative humidity and the speed of the pushed air layer above the top pool end on the evaporation rate is studied. The current study showed that, the hot water layer system is considered an efficient shielding system against gamma radiation for open pool upward flow reactor and that system should be operated before the reactor start up by a suitable period of time. While, the heat and mass transfer model results showed that, the amount of the released water vapour is increased as a result of both the increase in hot water layer surface temperature and the increase in air layer speed. As the increase in hot water layer surface temperature could produce a good operability conditions from

  10. A study on the effect of the injected absolute ethanol and hot-saline in the normal liver of rat

    International Nuclear Information System (INIS)

    Rhim, Hyun Chul; Hong, Eun Kyung; Cho, On Koo; Song, Soon Young; Koh, Byung Hee; Seo, Heung Suk; Hahm, Chang Kok; Park, Hwon Kyum

    1995-01-01

    To compare the effect of local injection therapy with absolute ethanol and hot-saline in the normal liver of rat. An experimental study was performed with the normal liver of 52 rats. The resected livers were pathologically analyzed on three days, one week, two weeks, and four weeks after injection of 0.1 ml absolute ethanol and hot-saline. The assessment was done in view of 1) main pathologic changes on time, 2) pattern of inflammatory cell infiltration, 3) measurement of necrotic area, 4) effect on vascular and biliary tracts adjacent to necrotic area, and 5) extrahepatic peritoneal adhesion. The main pathologic changes were acute necrosis with inflammation for three days group and secondary regenerative fibrosis in all groups. The degree of necrosis was significantly more severe in absolute ethanol injection group, demonstrating larger necrotic area, than hot-saline injection group. The effect on vessels and bile ducts adjacent to the necrotic area was almost not seen in both groups. The extrahepatic peritoneal adhesion was noted in both groups, but the degree was more prominent in the absolute ethanol injection group than hot-saline injection group. Absolute ethanol is superior to hot-saline in the necrotic effect of percutaneous injection therapy. However, hot-saline could be applied in case of the borderline area between mass and adjacent normal liver or the subcapsular mass

  11. Operation of a novel hot-electron vertical-cavity surface-emitting laser

    Science.gov (United States)

    Balkan, Naci; O'Brien-Davies, Angela; Thoms, A. B.; Potter, Richard J.; Poolton, Nigel; Adams, Michael J.; Masum, J.; Bek, Alpan; Serpenguzel, Ali; Aydinli, Atilla; Roberts, John S.

    1998-07-01

    The hot Electron Light Emission and Lasing in Semiconductor Heterostructures devices (HELLISH-1) is novel surface emitter consisting of a GaAs quantum well, within the depletion region, on the n side of Ga1-xAlxAs p- n junction. It utilizes hot electron transport parallel to the layers and injection of hot electron hole pairs into the quantum well through a combination of mechanisms including tunnelling, thermionic emission and diffusion of `lucky' carriers. Super Radiant HELLISH-1 is an advanced structure incorporating a lower distributed Bragg reflector (DBR). Combined with the finite reflectivity of the upper semiconductor-air interface reflectivity it defines a quasi- resonant cavity enabling emission output from the top surface with a higher spectral purity. The output power has increased by two orders of magnitude and reduced the full width at half maximum (FWHM) to 20 nm. An upper DBR added to the structure defines HELLISH-VCSEL which is currently the first operational hot electron surface emitting laser and lases at room temperature with a 1.5 nm FWHM. In this work we demonstrate and compare the operation of UB-HELLISH-1 and HELLISH-VCSEL using experimental and theoretical reflectivity spectra over an extensive temperature range.

  12. Hydrogen in hot subdwarfs formed by double helium white dwarf mergers

    OpenAIRE

    Hall, Philip D.; Jeffery, C. Simon

    2016-01-01

    Isolated hot subdwarfs might be formed by the merging of two helium-core white dwarfs. Before merging, helium-core white dwarfs have hydrogen-rich envelopes and some of this hydrogen may survive the merger. We calculate the mass of hydrogen that is present at the start of such mergers and, with the assumption that hydrogen is mixed throughout the disrupted white dwarf in the merger process, estimate how much can survive. We find a hydrogen mass of up to about $2 \\times 10^{-3}\\,\\mathrm{M}_{\\o...

  13. SMA spring-based artificial muscle actuated by hot and cool water using faucet-like valve

    Science.gov (United States)

    Park, Cheol Hoon; Son, Young Su

    2017-04-01

    An artificial muscle for a human arm-like manipulator with high strain and high power density are under development, and an SMA(Shape memory alloy) spring is a good actuator for this application. In this study, an artificial muscle composed of a silicon tube and a bundle of SMA(Shape memory alloy) springs is evaluated. A bundle of SMA springs consists of five SMA springs which are fabricated by using SMA wires with a diameter of 0.5 mm, and hot and cool water actuates it by heating and cooling SMA springs. A faucet-like valve was also developed to mix hot water and cool water and control the water temperature. The mass of silicon tube and a bundle of SMA springs is only 3.3 g and 2.25 g, respectively, and the total mass of artificial muscle is 5.55 g. It showed good actuating performance for a load with a mass of 2.3 kg and the power density was more than 800 W/kg for continuous valve switching with a cycle of 0.6 s. The faucet-like valve can switch a water output from hot water to cold water within 0.3s, and the artificial muscle is actuated well in response to the valve position and speed. It is also presented that the temperature of the mixed water can be controlled depending on the valve position, and the displacement of the artificial muscle can be controlled well by the mixed water. Based on these results, SMA spring-based artificial muscle actuated by hot and cool water could be applicable to the human arm-like robot manipulators.

  14. [Research on the temperature field detection method of hot forging based on long-wavelength infrared spectrum].

    Science.gov (United States)

    Zhang, Yu-Cun; Wei, Bin; Fu, Xian-Bin

    2014-02-01

    A temperature field detection method based on long-wavelength infrared spectrum for hot forging is proposed in the present paper. This method combines primary spectrum pyrometry and three-stage FP-cavity LCTF. By optimizing the solutions of three group nonlinear equations in the mathematical model of temperature detection, the errors are reduced, thus measuring results will be more objective and accurate. Then the system of three-stage FP-cavity LCTF was designed on the principle of crystal birefringence. The system realized rapid selection of any wavelength in a certain wavelength range. It makes the response of the temperature measuring system rapid and accurate. As a result, without the emissivity of hot forging, the method can acquire exact information of temperature field and effectively suppress the background light radiation around the hot forging and ambient light that impact the temperature detection accuracy. Finally, the results of MATLAB showed that the infrared spectroscopy through the three-stage FP-cavity LCTF could meet the requirements of design. And experiments verified the feasibility of temperature measuring method. Compared with traditional single-band thermal infrared imager, the accuracy of measuring result was improved.

  15. SECULAR CHAOS AND THE PRODUCTION OF HOT JUPITERS

    International Nuclear Information System (INIS)

    Wu Yanqin; Lithwick, Yoram

    2011-01-01

    In a planetary system with two or more well-spaced, eccentric, inclined planets, secular interactions may lead to chaos. The innermost planet may gradually become very eccentric and/or inclined as a result of the secular degrees of freedom drifting toward equipartition of angular momentum deficit. Secular chaos is known to be responsible for the eventual destabilization of Mercury in our own solar system. Here we focus on systems with three giant planets. We characterize the secular chaos and demonstrate the criterion for it to occur, but leave a detailed understanding of secular chaos to a companion paper. After an extended period of eccentricity diffusion, the inner planet's pericenter can approach the star to within a few stellar radii. Strong tidal interactions and ensuing tidal dissipation extract orbital energy from the planet and pull it inward, creating a hot Jupiter. In contrast to other proposed channels for the production of hot Jupiters, such a scenario (which we term 'secular migration') explains a range of observations: the pile-up of hot Jupiters at 3 day orbital periods, the fact that hot Jupiters are in general less massive than other radial velocity planets, that they may have misaligned inclinations with respect to stellar spin, and that they have few easily detectable companions (but may have giant companions in distant orbits). Secular migration can also explain close-in planets as low in mass as Neptune; and an aborted secular migration can explain the 'warm Jupiters' at intermediate distances. In addition, the frequency of hot Jupiters formed via secular migration increases with stellar age. We further suggest that secular chaos may be responsible for the observed eccentricities of giant planets at larger distances and that these planets could exhibit significant spin-orbit misalignment.

  16. Water chemistry management during hot functional test

    International Nuclear Information System (INIS)

    Yokoyama, Jiro; Kanda, Tomio; Kagawa, Masaru

    1988-01-01

    To reduce radiation exposure in light water reactor, it is important decrease radioactive corrosion product which is a radiation source. One of the countermeasures is to improve water quality during plant trial operation to form a stable oxide film and to minimize metal release to the coolant at the beginning of commercial operation. This study reviews the optimum water quality conditions to form a chromium rich oxide film during hot functional test (HFT) that is thought to be stable under the PWR condition and reduce the release of Ni that is the source of Co-58, the main radiation source of exposure. (author)

  17. Hot electron effects on the satellite spectrum of laser-produced plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Abdallah, J. [Los Alamos National Laboratory, PO Box 1663, Los Alamos, NM (United States); Faenov, A.Y.; Pikuz, T.A. [MISDC, NPO ' VNIIFTRI' , Mendeleevo, Moscow Region, 141570 (Russian Federation); Wilke, M.D.; Kyrala, G.A.; Clark, R.E.H. [Los Alamos National Laboratory, PO Box 1663, Los Alamos, NM (United States)

    1999-05-01

    In laser-produced plasmas, the interaction of the intense laser light with plasma electrons can produce high-energy superthermal electrons with energies in the keV range. These hot electrons can influence the level populations which determine spectral line structure. In the present paper, the effect of hot electrons on the X-ray satellite spectrum of laser-produced plasmas is studied. Calculated spectra are compared with experimental observations. Magnesium targets irradiated by three different types of laser pulses are considered. These include, a high-intensity 600 fs Nd-glass laser, a 1 ns Nd-glass laser, and a 2ns CO{sub 2} laser. The Nd-glass laser experiments were conducted recently at the Los Alamos Trident Facility and the CO{sub 2} data were recorded by MISDC. High-resolution spectra were measured near the He-like resonance line of magnesium. The calculations employ an electron energy distribution which includes a thermal and a hot electron component, as part of a detailed collisional-radiative model. Plasma parameters including electron temperature, density, and hot electron fraction are estimated by choosing best fits to the experimental measurements. The calculations show that hot electrons can cause several anomalous effects. The Li-like jkl, abcd, and qr satellites can show intensities which are generally attributed to electron densities in excess of 10{sup 23} cm{sup -3}. In addition, the relative amplitude of the intercombination line can be unusually large even at high electron densities due to enhanced collisional excitation of the 1s2p{sup 3}P state by hot electrons. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  18. Addition of electric arc furnace dust in hot metal changing the form of addition; Adicao de poeira de aciaria eletrica em ferro-gusa liquido alterando a forma de adicao

    Energy Technology Data Exchange (ETDEWEB)

    Marques Sobrinho, Vicente de Paulo Ferreira; Oliveira, Jose Roberto de; Vieira, Estefano Aparecido, E-mail: vicente@ifes.edu.br [Institulo Federal do Espirito Santo (IFES), ES (Brazil); Telles, Victor Bridi; Grillo, Felipe Fardin; Tenorio, Jorge Alberto Soares; Espinosa, Denise Crocce Romano [Universidade de Sao Paulo (USP), SP (Brazil). Escola Politecnica

    2014-07-01

    This research aims to study the incorporation of the mass of electric arc furnace dust (EAFD), by addition in hot metal (1.78% Si) at a temperature of 1,400 degrees Celsius. The EAFD is from a steel plant producing long steel. The addition of the EAFD was as received, in the form of briquettes without agitation of the hot metal and in the form of briquettes with agitation of the hot metal. Previously, the EAFD was characterized using the following techniques: chemical analysis, size analysis, X-ray diffraction, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) microanalysis. The achievement of fusion experiments in laboratory scale, took place in a vertical tubular furnace with temperature control. The fusion experiments to assess the incorporation of EAFD mass used graphite crucibles. After cooling, the hot metal and the slag, remaining in the crucible, were weighed to do a mass balance. A flow of inert gas (argon) was maintained inside the furnace during the experiments. Results show that the experiment with addition of EAFD as received presents the best result of incorporating the mass of the final hot metal (1.73%) combined with the lowest percentage of volatilized mass of EAFD (46.52%). The experiment addition of EAFD in the form of briquette with agitation of hot metal presents the lowest percentage of slag mass (4.58%). The zinc content of volatilized EAFD (64.30%) is higher than the zinc content of the imported ore concentrate (52%) and zinc content of the national ore concentrate (12% to 39%). The presence of lead and cadmium in the slag characterizing it as a hazardous solid waste. (author)

  19. Light hadrons from lattice QCD with light (u,d), strange and charm dynamical quarks

    Energy Technology Data Exchange (ETDEWEB)

    Baron, R. [CEA, Centre de Saclay, 91 - Gif-sur-Yvette (France). IRFU/Service de Physique Nucleaire; Boucaud, P. [CNRS et Paris-Sud 11 Univ., 91 - Orsay (France). Lab. de Physique Theorique; Carbonell, J. [Lab. de Physique Subatomique et Cosmologie, 38 - Grenoble (FR)] (and others)

    2010-04-15

    We present results of lattice QCD simulations with mass-degenerate up and down and mass-split strange and charm (N{sub f}=2+1+1) dynamical quarks using Wilson twisted mass fermions at maximal twist. The tuning of the strange and charm quark masses is performed at two values of the lattice spacing a {approx} 0:078 fm and a {approx}0.086 fm with lattice sizes ranging from L{approx}1.9 fm to L{approx}2.8 fm. We measure with high statistical precision the light pseudoscalar mass m{sub PS} and decay constant f{sub PS} in a range 270light, strange and charm quark masses to explore the systematic effects. A first study of discretisation effects in light-quark observables and a comparison to N{sub f}=2 results are performed. (orig.)

  20. New air Cherenkov light detectors to study mass composition of cosmic rays with energies above knee region

    Energy Technology Data Exchange (ETDEWEB)

    Tsunesada, Yoshiki, E-mail: tsunesada@cr.phys.titech.ac.jp [Graduate School of Science and Engineering, Tokyo Institute of Technology, Meguro, Tokyo 152-8550 Japan (Japan); Katsuya, Ryoichi, E-mail: katsuya@cr.phys.titech.ac.jp [Graduate School of Science and Engineering, Tokyo Institute of Technology, Meguro, Tokyo 152-8550 Japan (Japan); Mitsumori, Yu; Nakayama, Keisuke; Kakimoto, Fumio; Tokuno, Hisao [Graduate School of Science and Engineering, Tokyo Institute of Technology, Meguro, Tokyo 152-8550 Japan (Japan); Tajima, Norio [RIKEN, Wako, Saitama 351-0198 (Japan); Miranda, Pedro; Salinas, Juan; Tavera, Wilfredo [Instituto de Investigaciones Físicas, Universidad Mayor de San Andrés, La Paz (Bolivia, Plurinational State of)

    2014-11-01

    We have installed a hybrid detection system for air showers generated by cosmic rays with energies greater than 3×10{sup 15}eV at Mount Chacaltaya (5200 m above the sea level), in order to study the mass composition of cosmic rays above the knee region. This detection system comprises an air shower array with 49 scintillation counters in an area of 500 m×650 m, and seven new Cherenkov light detectors installed in a radial direction from the center of the air shower array with a separation of 50 m. It is known that the longitudinal development of a particle cascade in the atmosphere strongly depends on the type of the primary nucleus, and an air shower initiated by a heavier nucleus develops faster than that by a lighter primary of the same energy, because of the differences in the interaction cross-section and the energy per nucleon. This can be measured by detecting the Cherenkov radiation emitted from charged particles in air showers at higher altitudes. In this paper we describe the design and performance of our new non-imaging Cherenkov light detectors at Mount Chacaltaya that are operated in conjunction with the air shower array. The arrival directions and energies of air showers are determined by the shower array, and information about the primary masses is obtained from the Cherenkov light data including the time profiles and lateral distributions. The detector consists of photomultiplier tube (PMT), high-speed ADCs, other control modules, and data storage device. The Cherenkov light signals from an air shower are typically 10–100 ns long, and the waveforms are digitized with a sampling frequency of 1 GHz and recorded in situ without long-distance analog signal transfers. All the Cherenkov light detectors record their time-series data by receiving a triggering signal transmitted from the trigger module of the air shower array, which is fired by a coincidence of shower signals in four neighboring scintillation counters. The optical characteristics of the

  1. Study of Low Work Function Materials for Hot Cavity Resonance Ionization Laser Ion Sources

    CERN Document Server

    Catherall, R; Fedosseev, V; Marsh, B; Mattolat, C; Menna, Mariano; Österdahl, F; Raeder, S; Schwellnus, F; Stora, T; Wendt, K; CERN. Geneva. AB Department

    2008-01-01

    The selectivity of a hot cavity resonance ionization laser ion source (RILIS) is most often limited by contributions from competing surface ionization on the hot walls of the ionization cavity. In this article we present investigations on the properties of designated high-temperature, low-work function materials regarding their performance and suitability as cavity material for RILIS. Tungsten test cavities, impregnated with a mixture of barium oxide and strontium oxide (BaOSrO on W), or alternatively gadolinium hexaboride (GdB6) were studied in comparison to a standard tungsten RILIS cavity as being routinely used for hot cavity laser ionization at ISOLDE. Measurement campaigns took place at the off-line mass separators at ISOLDE / CERN, Geneva and RISIKO / University of Mainz.

  2. Study of low work function materials for hot cavity resonance ionization laser ion sources

    CERN Document Server

    Schwellnus, F; Crepieux, B; Fedosseev, V N; Marsh, B A; Mattolat, Ch; Menna, M; Österdahl, F K; Raeder, S; Stora, T; Wendta, K

    2009-01-01

    The selectivity of a hot cavity resonance ionization laser ion source (RILIS) is most often limited by contributions from competing surface ionization of the hot walls of the ionization cavity. In this article we present investigations on the properties of designated high temperature, low work function materials regarding their performance and suitability as cavity material for RILIS. Tungsten test cavities, impregnated with a mixture of barium oxide and strontium oxide (BaOSrO on W), or alternatively gadolinium hexaboride (GdB6) were studied in comparison to a standard tungsten RILIS cavity as being routinely used for hot cavity laser ionization at ISOLDE. Measurement campaigns took place at the off-line mass separators at ISOLDE/CERN, Geneva and RISIKO/University of Mainz.

  3. A novel design and analysis of a MEMS ceramic hot-wire anemometer for high temperature applications

    International Nuclear Information System (INIS)

    Nagaiah, N R; Sleiti, A K; Rodriguez, S; Kapat, J S; An, L; Chow, L

    2006-01-01

    This paper attempts to prove the feasibility of high temperature MEMS hot-wire anemometer for gas turbine environment. No such sensor exists at present. Based on the latest improvement in a new type of Polymer-Derived Ceramic (PDC) material, the authors present a Novel design, structural and thermal analysis of MEMS hot-wire anemometer (HWA) based on PDC material, and show that such a sensor is indeed feasible. This MEMS Sensor is microfabricated by using three types of PDC materials such as SiAlCN, SiCN (lightly doped) and SiCN (heavily doped) for sensing element (hot-wire), support prongs and connecting leads respectively. This novel hot wire anemometer can perform better than a conventional HWA in which the hot wire is made of tungsten or platinum-iridium. This type of PDC-HWA can be used in harsh environment due to its high temperature resistance, tensile strength and resistance to oxidation. This HWA is fabricated using microstereolithography as a novel microfabrication technique to manufacture the proposed MEMS Sensor

  4. A novel solar hot plate for cooking

    Energy Technology Data Exchange (ETDEWEB)

    Rincon Mejia, Eduardo A; Osorio Jaramillo, Fidel A [Facultad de Ingenieria, UAEMex, Toluca, Edo. (Mexico)

    2000-07-01

    In Mexico and other developing countries, the use of firewood as combustible for cooking has contributed to deforestation and desertification of large zones. This is due to the lack of alternative combustibles for the poor inhabitants of the countryside and remote areas. In this paper, a new solar hot plate, intended for contributing to solve this problem, is presented. It can be used for cooking not only a great variety of prehispanic and traditional meals, like tortillas, fried meat and vegetables, but also hot cakes, bacon, eggs, steaks and fries. The hot plate solar cooker, called Tolocatzin, consists of a horizontal metallic plate, which is heated from both of its top and bottom surfaces by concentrated sun light from multicompound concentrator based on nonimaging optics, and built with nine ordinary plane glass-silvered, and two curved aluminum mirrors, so it can be manufactured easily in a small factory or at home. For an acceptance angle of 15 Celsius degrees, which allows the concentration of sun light without sun-tracking for about one hour, it can reach temperatures up to 240 Celsius degrees in a few minutes. This temperature is high enough for cooking almost all fried or grilled meals. The design was optimized using ray-trace procedures. The operational experience with early prototypes has shown that the Tolocatzin solar hot plate does an excellent cooking job and could really be massively used in sunny countries. [Spanish] En Mexico y otros paises en desarrollo, el uso de la madera como combustible para cocinar ha contribuido a la deforestacion y desertificacion de grandes zonas. Esto es debido a la falta de combustibles alternativos por parte de los habitantes pobres del campo y de areas remotas. En este articulo se presenta una nueva placa solar que tiene el proposito de contribuir a resolver este problema. Puede ser usada para cocinar no solamente una gran variedad de comidas prehispanicas y tradicionales, como tortillas, carne frita y verduras sino

  5. Heavy quark masses

    Science.gov (United States)

    Testa, Massimo

    1990-01-01

    In the large quark mass limit, an argument which identifies the mass of the heavy-light pseudoscalar or scalar bound state with the renormalized mass of the heavy quark is given. The following equation is discussed: m(sub Q) = m(sub B), where m(sub Q) and m(sub B) are respectively the mass of the heavy quark and the mass of the pseudoscalar bound state.

  6. Splitting of ISGMR strength in the light-mass nucleus 24Mg due to ground-state deformation

    Directory of Open Access Journals (Sweden)

    Y.K. Gupta

    2015-09-01

    Full Text Available The isoscalar giant monopole resonance (ISGMR strength distribution in 24Mg has been determined from background-free inelastic scattering of 386-MeV α particles at extreme forward angles, including 0∘. The ISGMR strength distribution has been observed for the first time to have a two-peak structure in a light-mass nucleus. This splitting of ISGMR strength is explained well by microscopic theory in terms of the prolate deformation of the ground state of 24Mg.

  7. Cyclic Oxidation and Hot Corrosion Behavior of Nickel-Iron-Based Superalloy

    Science.gov (United States)

    Chellaganesh, D.; Adam Khan, M.; Winowlin Jappes, J. T.; Sathiyanarayanan, S.

    2018-01-01

    The high temperature oxidation and hot corrosion behavior of nickel-iron-based superalloy are studied at 900 ° and 1000 °C. The significant role of alloying elements with respect to the exposed medium is studied in detail. The mass change per unit area was catastrophic for the samples exposed at 1000 °C and gradual increase in mass change was observed at 900 °C for both the environments. The exposed samples were further investigated with SEM, EDS and XRD analysis to study the metallurgical characteristics. The surface morphology has expressed the in situ nature of the alloy and its affinity toward the environment. The EDS and XRD analysis has evidently proved the presence of protective oxides formation on prolonged exposure at elevated temperature. The predominant oxide formed during the exposure at high temperature has a major contribution toward the protection of the samples. The nickel-iron-based superalloy is less prone to oxidation and hot corrosion when compared to the existing alloy in gas turbine engine simulating marine environment.

  8. Au nanoparticle-decorated silicon pyramids for plasmon-enhanced hot electron near-infrared photodetection

    Science.gov (United States)

    Qi, Zhiyang; Zhai, Yusheng; Wen, Long; Wang, Qilong; Chen, Qin; Iqbal, Sami; Chen, Guangdian; Xu, Ji; Tu, Yan

    2017-07-01

    The heterojunction between metal and silicon (Si) is an attractive route to extend the response of Si-based photodiodes into the near-infrared (NIR) region, so-called Schottky barrier diodes. Photons absorbed into a metallic nanostructure excite the surface plasmon resonances (SPRs), which can be damped non-radiatively through the creation of hot electrons. Unfortunately, the quantum efficiency of hot electron detectors remains low due to low optical absorption and poor electron injection efficiency. In this study, we propose an efficient and low-cost plasmonic hot electron NIR photodetector based on a Au nanoparticle (Au NP)-decorated Si pyramid Schottky junction. The large-area and lithography-free photodetector is realized by using an anisotropic chemical wet etching and rapid thermal annealing (RTA) of a thin Au film. We experimentally demonstrate that these hot electron detectors have broad photoresponsivity spectra in the NIR region of 1200-1475 nm, with a low dark current on the order of 10-5 A cm-2. The observed responsivities enable these devices to be competitive with other reported Si-based NIR hot electron photodetectors using perfectly periodic nanostructures. The improved performance is attributed to the pyramid surface which can enhance light trapping and the localized electric field, and the nano-sized Au NPs which are beneficial for the tunneling of hot electrons. The simple and large-area preparation processes make them suitable for large-scale thermophotovoltaic cell and low-cost NIR detection applications.

  9. Explaining dark matter and neutrino mass in the light of TYPE-II seesaw model

    Science.gov (United States)

    Biswas, Anirban; Shaw, Avirup

    2018-02-01

    With the motivation of simultaneously explaining dark matter and neutrino masses, mixing angles, we have invoked the Type-II seesaw model extended by an extra SU(2) doublet Φ. Moreover, we have imposed a Z2 parity on Φ which remains unbroken as the vacuum expectation value of Φ is zero. Consequently, the lightest neutral component of Φ becomes naturally stable and can be a viable dark matter candidate. On the other hand, light Majorana masses for neutrinos have been generated following usual Type-II seesaw mechanism. Further in this framework, for the first time we have derived the full set of vacuum stability and unitarity conditions, which must be satisfied to obtain a stable vacuum as well as to preserve the unitarity of the model respectively. Thereafter, we have performed extensive phenomenological studies of both dark matter and neutrino sectors considering all possible theoretical and current experimental constraints. Finally, we have also discussed a qualitative collider signatures of dark matter and associated odd particles at the 13 TeV Large Hadron Collider.

  10. UBV Light Curves of ζ AUR Star 32 Cygni

    Directory of Open Access Journals (Sweden)

    Il-Seong Nha

    1992-12-01

    Full Text Available UBV ovservation of ζ Aur star 32 Cyg have been at the Yonsei University Observatory suing the 60-cm Goto reflector and five years, 1988-1992. Observations made during these years cover outside of eclipse phase only. No significant light variation which would represent the secondary eclipse of red supergiant by a hot main sequence star is found. The light levels in three passbands do not show any evidence of the proximate effect of this binary system. Some strong light variations, particularly in U, are discussed with no successful explanation.

  11. Hot Surface Ignition

    OpenAIRE

    Tursyn, Yerbatyr; Goyal, Vikrant; Benhidjeb-Carayon, Alicia; Simmons, Richard; Meyer, Scott; Gore, Jay P.

    2015-01-01

    Undesirable hot surface ignition of flammable liquids is one of the hazards in ground and air transportation vehicles, which primarily occurs in the engine compartment. In order to evaluate the safety and sustainability of candidate replacement fuels with respect to hot surface ignition, a baseline low lead fuel (Avgas 100 LL) and four experimental unleaded aviation fuels recommended for reciprocating aviation engines were considered. In addition, hot surface ignition properties of the gas tu...

  12. Bump masses for BL Her stars

    International Nuclear Information System (INIS)

    Davis, C.G.

    1982-01-01

    The masses of classical Cepheids can be determined by using the phase of the Hertzsprung bump on the light or velocity curve, Cox-Stewart opacities, and nonlinear pulsation theory. The fact that these bump masses are some 60% lower than the evolutionary masses raises some questions about this approach. In support of our method, we calculate the light curve for BL Her, a population II Cepheid, with an observed bump on the declining portion of its light curve. The nonlinear hydrodynamic model we use (Davis and Davison - 1978) resolves the light curve by dynamic zoning and allows us the opportunity to make a direct comparison of the calculated light curve to the observations, using a prescribed mass, luminosity and effective temperature. The parameters for BL Her are from a linear model (Hodson, Cox, and King - 1982) that has nearly the correct period (1./sup d/2) and the correct period ratio from resonance theory (π 2 /π 0 = 0.53) for a bump to appear on the declining portion of the light curve as observed. These parameters are: M = 0.55 M, L = 95.0 L, and T/sub eff/ = 6500 K. This mass is near the evolutionary mass as described by Schwartzschild and Haerm (1970). The model results agree well with the observations and the color-T/sub eff/ relation has the same slope as that observed for RR Lyrae stars by the Oke, Giver and Searle (1965) relationship

  13. Disaggregating Hot Water Use and Predicting Hot Water Waste in Five Test Homes

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, H.; Wade, J.

    2014-04-01

    While it is important to make the equipment (or 'plant') in a residential hot water system more efficient, the hot water distribution system also affects overall system performance and energy use. Energy wasted in heating water that is not used is estimated to be on the order of 10 to 30 percent of total domestic hot water (DHW) energy use. This field monitoring project installed temperature sensors on the distribution piping (on trunks and near fixtures) and programmed a data logger to collect data at 5 second intervals whenever there was a hot water draw. This data was used to assign hot water draws to specific end uses in the home as well as to determine the portion of each hot water that was deemed useful (i.e., above a temperature threshold at the fixture). Five houses near Syracuse NY were monitored. Overall, the procedures to assign water draws to each end use were able to successfully assign about 50% of the water draws, but these assigned draws accounted for about 95% of the total hot water use in each home. The amount of hot water deemed as useful ranged from low of 75% at one house to a high of 91% in another. At three of the houses, new water heaters and distribution improvements were implemented during the monitoring period and the impact of these improvements on hot water use and delivery efficiency were evaluated.

  14. Disaggregating Hot Water Use and Predicting Hot Water Waste in Five Test Homes

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, Hugh [ARIES Collaborative, New York, NY (United States); Wade, Jeremy [ARIES Collaborative, New York, NY (United States)

    2014-04-01

    While it is important to make the equipment (or "plant") in a residential hot water system more efficient, the hot water distribution system also affects overall system performance and energy use. Energy wasted in heating water that is not used is estimated to be on the order of 10%-30% of total domestic hot water (DHW) energy use. This field monitoring project installed temperature sensors on the distribution piping (on trunks and near fixtures) in five houses near Syracuse, NY, and programmed a data logger to collect data at 5 second intervals whenever there was a hot water draw. This data was used to assign hot water draws to specific end uses in the home as well as to determine the portion of each hot water that was deemed useful (i.e., above a temperature threshold at the fixture). Overall, the procedures to assign water draws to each end use were able to successfully assign about 50% of the water draws, but these assigned draws accounted for about 95% of the total hot water use in each home. The amount of hot water deemed as useful ranged from low of 75% at one house to a high of 91% in another. At three of the houses, new water heaters and distribution improvements were implemented during the monitoring period and the impact of these improvements on hot water use and delivery efficiency were evaluated.

  15. Hot Jupiters Aren't As Lonely As We Thought

    Science.gov (United States)

    Kohler, Susanna

    2016-01-01

    The Friends of Hot Jupiters (FOHJ) project is a systematic search for planetary- and stellar-mass companions in systems that have known hot Jupiters short-period, gas-giant planets. This survey has discovered that many more hot Jupiters may have companions than originally believed.Missing FriendsFOHJ was begun with the goal of better understanding the systems that host hot Jupiters, in order to settle several longstanding issues.The first problem was one of observational statistics. We know that roughly half of the Sun-like stars nearby are in binary systems, yet weve only discovered a handful of hot Jupiters around binaries. Are binary systems less likely to host hot Jupiters? Or have we just missed the binary companions in the hot-Jupiter-hosting systems weve seen so far?An additional issue relates to formation mechanisms. Hot Jupiters probably migrated inward from where they formed out beyond the ice lines in protoplanetary disks but how?This median-stacked image, obtained with adaptive optics, shows one of the newly-discovered stellar companions to a star hosting a hot Jupiter. The projected separation is ~180 AU. [Ngo et al. 2015]Observations reveal two populations of hot Jupiters: those with circular orbits aligned with their hosts spins, and those with eccentric, misaligned orbits. The former population support a migration model dominated by local planet-disk interactions, whereas the latter population suggest the hot Jupiters migrated through dynamical interactions with distant companions. A careful determination of the companion rate in hot-Jupiter-hosting systems could help establish the ability of these two models to explain the observed populations.Search for CompanionsThe FOHJ project began in 2012 and studied 51 systems hosting known, transiting hot Jupiters with roughly half on circular, aligned orbits and half on eccentric, misaligned orbits. The survey consisted of three different, complementary components:Study 1Lead author: Heather Knutson

  16. Relationship between hot spot residues and ligand binding hot spots in protein-protein interfaces.

    Science.gov (United States)

    Zerbe, Brandon S; Hall, David R; Vajda, Sandor; Whitty, Adrian; Kozakov, Dima

    2012-08-27

    In the context of protein-protein interactions, the term "hot spot" refers to a residue or cluster of residues that makes a major contribution to the binding free energy, as determined by alanine scanning mutagenesis. In contrast, in pharmaceutical research, a hot spot is a site on a target protein that has high propensity for ligand binding and hence is potentially important for drug discovery. Here we examine the relationship between these two hot spot concepts by comparing alanine scanning data for a set of 15 proteins with results from mapping the protein surfaces for sites that can bind fragment-sized small molecules. We find the two types of hot spots are largely complementary; the residues protruding into hot spot regions identified by computational mapping or experimental fragment screening are almost always themselves hot spot residues as defined by alanine scanning experiments. Conversely, a residue that is found by alanine scanning to contribute little to binding rarely interacts with hot spot regions on the partner protein identified by fragment mapping. In spite of the strong correlation between the two hot spot concepts, they fundamentally differ, however. In particular, while identification of a hot spot by alanine scanning establishes the potential to generate substantial interaction energy with a binding partner, there are additional topological requirements to be a hot spot for small molecule binding. Hence, only a minority of hot spots identified by alanine scanning represent sites that are potentially useful for small inhibitor binding, and it is this subset that is identified by experimental or computational fragment screening.

  17. Fermion mass hierarchies in theories of technicolor

    International Nuclear Information System (INIS)

    Peskin, M.E.

    1981-01-01

    Models in which light fermion masses result from dynamical symmetry breaking often produce these masses in a hierarchial pattern. The author exhibits two scenarios for obtaining such hierarchies and illustrates each with a simple model of mass generation. In the first scenario, the light fermion masses are separated by powers of a weak coupling constant; in the second scenario, they are separated by a ratio of large mass scales

  18. The multiwavelength spectrum of NGC 3115: hot accretion flow properties

    Science.gov (United States)

    Almeida, Ivan; Nemmen, Rodrigo; Wong, Ka-Wah; Wu, Qingwen; Irwin, Jimmy A.

    2018-04-01

    NGC 3115 is the nearest galaxy hosting a billion solar mass black hole and is also a low-luminosity active galactic nucleus (LLAGN). X-ray observations of this LLAGN are able to spatially resolve the hot gas within the sphere of gravitational influence of the supermassive black hole. These observations make NGC 3115 an important test bed for black hole accretion theory in galactic nuclei since they constrain the outer boundary conditions of the hot accretion flow. We present a compilation of the multiwavelength spectral energy distribution (SED) of the nucleus of NGC 3115 from radio to X-rays. We report the results from modelling the observed SED with radiatively inefficient accretion flow (RIAF) models. The radio emission can be well-explained by synchrotron emission from the RIAF without the need for contribution from a relativistic jet. We obtain a tight constraint on the RIAF density profile, ρ (r) ∝ r^{-0.73 _{-0.02} ^{+0.01}}, implying that mass-loss through subrelativistic outflows from the RIAF is significant. The lower frequency radio observation requires the synchrotron emission from a non-thermal electron population in the RIAF, similarly to Sgr A*.

  19. Energy flux of hot atoms

    International Nuclear Information System (INIS)

    Wotzak, G.P.; Kostin, M.D.

    1976-01-01

    The process in which hot atoms collide with thermal atoms of a gas, transfer kinetic energy to them, and produce additional hot atoms is investigated. A stochastic method is used to obtain numerical results for the spatial and time dependent energy flux of hot atoms in a gas. The results indicate that in hot atom systems a front followed by an intense energy flux of hot atoms may develop

  20. Corrosion penetration monitoring of advanced ceramics in hot aqueous fluids

    Directory of Open Access Journals (Sweden)

    Klaus G. Nickel

    2004-03-01

    Full Text Available Advanced ceramics are considered as components in energy related systems, because they are known to be strong, wear and corrosion resistant in many environments, even at temperatures well exceeding 1000 °C. However, the presence of additives or impurities in important ceramics, for example those based on Silicon Nitride (Si3N4 or Al2O3 makes them vulnerable to the corrosion by hot aqueous fluids. The temperatures in this type of corrosion range from several tens of centigrade to hydrothermal conditions above 100 °C. The corrosion processes in such media depend on both pH and temperature and include often partial leaching of the ceramics, which cannot be monitored easily by classical gravimetric or electrochemical methods. Successful corrosion penetration depth monitoring by polarized reflected light optical microscopy (color changes, Micro Raman Spectroscopy (luminescence changes and SEM (porosity changes will be outlined. The corrosion process and its kinetics are monitored best by microanalysis of cross sections, Raman spectroscopy and eluate chemistry changes in addition to mass changes. Direct cross-calibrations between corrosion penetration and mechanical strength is only possible for severe corrosion. The methods outlined should be applicable to any ceramics corrosion process with partial leaching by fluids, melts or slags.

  1. Modelling Hot Air Balloons.

    Science.gov (United States)

    Brimicombe, M. W.

    1991-01-01

    A macroscopic way of modeling hot air balloons using a Newtonian approach is presented. Misleading examples using a car tire and the concept of hot air rising are discussed. Pressure gradient changes in the atmosphere are used to explain how hot air balloons work. (KR)

  2. ATLAS Event Display: Light-by-Light Scattering

    CERN Multimedia

    ATLAS Collaboration

    2017-01-01

    An event display of light-by-light scattering in ultra-peripheral lead+lead collisions at 5.02 TeV with the ATLAS detector at the LHC. The event 461251458 from run 287931 recorded on 13 December 2015 at 09:51:07 is shown. Two back-to-back photons with an invariant mass of 24 GeV with no additional activity in the detector are presented. All calorimeter cells with E>500 MeV are shown.

  3. Heavy-to-light correlators beyond the light cone

    International Nuclear Information System (INIS)

    Lucha, W.; Melikhov, D. I.; Simula, S.

    2008-01-01

    We present the first systematic analysis of the off-light-cone effects in correlators relevant for the extraction of the heavy-to-light form factors within the method of light-cone sum rules. In a model with scalar constituents, the correlator is calculated in two different ways: (i) by performing the expansion of the Bethe-Salpeter amplitude of the light meson near the light cone x 2 = 0 and (ii) by adopting the known solution for the Bethe-Salpeter amplitude which allows one to calculate the correlator without invoking any expansion. We demonstrate that the contributions to the correlator from the off-light-cone terms x 2 ≠ 0 are not suppressed by any large parameter compared to the contribution of the light-cone term x 2 0. For decays of heavy particles of mass in the range 1.5-5 GeV, the light-cone correlator is shown to systematically overestimate the full correlator, numerically the difference being 10-20%

  4. Heavy-to-light correlators beyond the light cone

    International Nuclear Information System (INIS)

    Lucha, W.; Melikhov, D. I.; Simula, S.

    2008-01-01

    We present the first systematic analysis of the off-light-cone effects in correlators relevant for the extraction of the heavy-to-light form factors within the method of light-cone sum rules. In a model with scalar constituents, the correlator is calculated in two different ways: (i) by performing the expansion of the Bethe-Salpeter amplitude of the light meson near the light cone x 2 = 0 and (ii) by adopting the known solution for the Bethe-Salpeter amplitude which allows one to calculate the correlator without invoking any expansion. We demonstrate that the contributions to the correlator from the off-light-cone terms x 2 ≠ 0 are not suppressed by any large parameter compared to the contribution of the light-cone term x 2 = 0. For decays of heavy particles of mass in the range 1.5–5 GeV, the light-cone correlator is shown to systematically overestimate the full correlator, numerically the difference being 10–20%.

  5. NuSTAR Observations of WISE J1036+0449, A Galaxy at zeta approx 1 Obscured by Hot Dust

    Science.gov (United States)

    Ricci, C.; Assef, R. J.; Stern, Daniel K.; Nikutta, R.; Alexander, D. M.; Asmus, D.; Ballantyne, D. R.; Bauer, F. E.; Blain, A.W.; Zhang, William W.; hide

    2017-01-01

    Hot dust-obscured galaxies (hot DOGs), selected from Wide-Field Infrared Survey Explorer's all-sky infrared survey, host some of the most powerful active galactic nuclei known and may represent an important stage in the evolution of galaxies. Most known hot DOGs are located at z > 1.5, due in part to a strong bias against identifying them at lower redshift related to the selection criteria. We present a new selection method that identifies 153 hot DOG candidates at z approx. 1, where they are significantly brighter and easier to study. We validate this approach by measuring a redshift z = 1.009 and finding a spectral energy distribution similar to that of higher-redshift hot DOGs for one of these objects, WISE J1036+0449 (L(sub BOL) approx. = 8 x 10(exp 46) erg/s). We find evidence of a broadened component in Mg II, which would imply a black hole mass of M(BH) approx. = 2 x 10(exp 8) Stellar Mass and an Eddington ratio of lambda(sub Edd) approx. = 2.7. WISE J1036+0449 is the first hot DOG detected by the Nuclear Spectroscopic Telescope Array, and observations show that the source is heavily obscured, with a column density of N(sub H) approx. = (2-15) x 10(exp 23)/sq cm. The source has an intrinsic 2-10 keV luminosity of approx. 6 x 10(exp 44) erg/s, a value significantly lower than that expected from the mid-infrared X-ray correlation. We also find that other hot DOGs observed by X-ray facilities show a similar deficiency of X-ray flux. We discuss the origin of the X-ray weakness and the absorption properties of hot DOGs. Hot DOGs at z < or approx. 1 could be excellent laboratories to probe the characteristics of the accretion flow and of the X-ray emitting plasma at extreme values of the Eddington ratio.

  6. NuSTAR Observations of WISE J1036+0449, A Galaxy at Z Approx. 1 Obscured by Hot Dust

    Science.gov (United States)

    Ricci, C.; Assef, R. J.; Stern, D.; Nikutta, R.; Alexander, D. M.; Asmus, D.; Ballantyne, D. R.; Bauer, F. E.; Blain, A. W.; Boggs, S.; hide

    2017-01-01

    Hot dust-obscured galaxies (hot DOGs), selected from Wide-Field Infrared Survey Explorer's all-sky infrared survey, host some of the most powerful active galactic nuclei known and may represent an important stage in the evolution of galaxies. Most known hot DOGs are located at z > 1.5, due in part to a strong bias against identifying them at lower redshift related to the selection criteria. We present a new selection method that identifies 153 hot DOG candidates at z approx. 1, where they are significantly brighter and easier to study. We validate this approach by measuring a redshift z = 1.009 and finding a spectral energy distribution similar to that of higher-redshift hot DOGs for one of these objects, WISE J1036+0449 (L(BOL) approx. = 8 x 10(exp 46) erg/s). We find evidence of a broadened component in Mg II, which would imply a black hole mass of M(BH) approx. = 2 x 10(exp 8) Stellar Mass and an Eddington ratio of lambda(Edd) approx. = 2.7. WISE J1036+0449 is the first hot DOG detected by the Nuclear Spectroscopic Telescope Array, and observations show that the source is heavily obscured, with a column density of N(H) approx. = (2-15) x 10(exp 23)/sq cm. The source has an intrinsic 2-10 keV luminosity of approx. 6 x 10(exp 44) erg/s, a value significantly lower than that expected from the mid-infrared X-ray correlation. We also find that other hot DOGs observed by X-ray facilities show a similar deficiency of X-ray flux. We discuss the origin of the X-ray weakness and the absorption properties of hot DOGs. Hot DOGs at z < or approx. 1 could be excellent laboratories to probe the characteristics of the accretion flow and of the X-ray emitting plasma at extreme values of the Eddington ratio.

  7. Modeling Nearly Spherical Pure-bulge Galaxies with a Stellar Mass-to-light Ratio Gradient under the ΛCDM and MOND Paradigms. I. Methodology, Dynamical Stellar Mass, and Fundamental Mass Plane

    Science.gov (United States)

    Chae, Kyu-Hyun; Bernardi, Mariangela; Sheth, Ravi K.

    2018-06-01

    We carry out spherical Jeans modeling of nearly round pure-bulge galaxies selected from the ATLAS3D sample. Our modeling allows for gradients in the stellar mass-to-light ratio (M ⋆/L) through analytic prescriptions parameterized with a “gradient strength” K introduced to accommodate any viable gradient. We use a generalized Osipkov–Merritt model for the velocity dispersion (VD) anisotropy. We produce Monte Carlo sets of models based on the stellar VD profiles under both the ΛCDM and MOND paradigms. Here, we describe the galaxy data, the empirical inputs, and the modeling procedures of obtaining the Monte Carlo sets. We then present the projected dynamical stellar mass, {M}\\star {{e}}, within the effective radius R e, and the fundamental mass plane (FMP) as a function of K. We find the scaling of the K-dependent mass with respect to the ATLAS3D reported mass as: {log}}10[{M}\\star {{e}}(K)/{M}\\star {{e}}{{A}3{{D}}}]=a\\prime +b\\prime K with a‧ = ‑0.019 ± 0.012 and b‧ = ‑0.18 ± 0.02 (ΛCDM), or a‧ = ‑0.023 ± 0.014 and b‧ = ‑0.23 ± 0.03 (MOND), for 0 ≤ K expectation and only the zero-point scales with K. The median value of K for the ATLAS3D galaxies is ={0.53}-0.04+0.05. We perform a similar analysis of the much larger SDSS DR7 spectroscopic sample. In this case, only the VD within a single aperture is available, so we impose the additional requirement that the VD slope be similar to that in the ATLAS3D galaxies. Our analysis of the SDSS galaxies suggests a positive correlation of K with stellar mass.

  8. Effects of Galaxy collisions on the structure and evolution of Galaxy clusters. I. Mass and luminosity functions and background light

    International Nuclear Information System (INIS)

    Miller, G.E.; Department of Astronomy, University of Texas at Austin)

    1983-01-01

    The role of galaxy collisions in controlling the form of the galaxy mass and luminosity functions and in creating a diffuse background light is investigated by means of a direct computer simulation. Galaxy collisions are treated in a realistic manner, including both galaxy mergers and tidal encounters. A large number of theoretical studies of a galaxy collisions were consulted to formulate the basic input physics of collision cross sections. Despite this large number of studies, there remains considerable uncertainty in the effects of a collision on a galaxy due mainly to our lack of knowledge of the orbital distribution of matter in galaxies. To improve this situation, some methods of semiempirical calibration are suggested: for example, a survey of background light in clusters of different richness and morphological classes. If real galaxies are represented by galaxy models where the bulk of the matter is on radial, rather than circular, orbits, then tidal collisions are more damaging and there are a number of interesting effects: Repeated tidal encounters lead to galaxy mass and luminosity functions which are largely independent of model parameters and the initial galaxy mass function. It appears unlikely that the form of the average present-day luminosity function characteristic of both field and cluster galaxies is due to collisions, but certain observed deviations from the average found by Heiligman and Turner and by Dressler may be a signature of collisions, in particular a flat faint-end slope. The amount of luminous matter stripped from the galaxies in the simulations agrees with the amount of diffuse background light seen in the Coma Cluster

  9. Software Simulation of Hot Tearing

    DEFF Research Database (Denmark)

    Andersen, S.; Hansen, P.N.; Hattel, Jesper Henri

    1999-01-01

    The brittleness of a solidifying alloy in a temperature range near the solidus temperature has been recognised since the fifties as the mechanism responsible for hot tearing. Due to this brittlenes, the metal will crack under even small amounts of strain in that temperature range. We see these hot...... tears in castings close to hot centres, where the level of strain is often too high.Although the hot tearing mechanism is well understood, until now it has been difficult to do much to reduce the hot tearing tendency in a casting. In the seventies, good hot tearing criteria were developed by considering...... the solidification rate and the strain rate of the hot tear prone areas. But, until recently it was only possible to simulate the solidification rate, so that the criteria could not be used effectively.Today, with new software developments, it is possible to also simulate the strain rate in the hot tear prone areas...

  10. Hot composite systems with a > 200 and T > 6 MeV

    International Nuclear Information System (INIS)

    Crema, E.; Bresson, S.; Doubre, H.; Galin, J.; Guerreau, D.; Morjean, M.; Piasecki, E.; Pouthas, J.; Saint-Laurent, F.; Sokolov, A.; Wang, X.M.; Gatty, B.; Jacquet, D.; Piasecki, E.; Crema, E.; Wang, X.M.

    1990-01-01

    Neutron multiplicities have been measured in coincidence with the light charged particles evaporated in the backward direction for the reaction 84 Kr+ 197 Au at 32 MeV/u. A method is presented which makes possible an evaluation of the recoil velocity, excitation energy and temperature of hot and thermalized heavy composite systems formed for different impact parameters. Temperatures larger than 6 MeV are found for the most dissipative collisions

  11. THREE-DIMENSIONAL ATMOSPHERIC CIRCULATION OF WARM AND HOT JUPITERS: EFFECTS OF ORBITAL DISTANCE, ROTATION PERIOD, AND NONSYNCHRONOUS ROTATION

    Energy Technology Data Exchange (ETDEWEB)

    Showman, Adam P. [Department of Planetary Sciences and Lunar and Planetary Laboratory, University of Arizona, 1629 University Blvd., Tucson, AZ 85721 (United States); Lewis, Nikole K. [Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Fortney, Jonathan J., E-mail: showman@lpl.arizona.edu [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States)

    2015-03-10

    Efforts to characterize extrasolar giant planet (EGP) atmospheres have so far emphasized planets within 0.05 AU of their stars. Despite this focus, known EGPs populate a continuum of orbital separations from canonical hot Jupiter values (0.03–0.05 AU) out to 1 AU and beyond. Unlike typical hot Jupiters, these more distant EGPs will not generally be synchronously rotating. In anticipation of observations of this population, we here present three-dimensional atmospheric circulation models exploring the dynamics that emerge over a broad range of rotation rates and incident stellar fluxes appropriate for warm and hot Jupiters. We find that the circulation resides in one of two basic regimes. On typical hot Jupiters, the strong day–night heating contrast leads to a broad, fast superrotating (eastward) equatorial jet and large day–night temperature differences. At faster rotation rates and lower incident fluxes, however, the day–night heating gradient becomes less important, and baroclinic instabilities emerge as a dominant player, leading to eastward jets in the midlatitudes, minimal temperature variations in longitude, and, often, weak winds at the equator. Our most rapidly rotating and least irradiated models exhibit similarities to Jupiter and Saturn, illuminating the dynamical continuum between hot Jupiters and the weakly irradiated giant planets of our own solar system. We present infrared (IR) light curves and spectra of these models, which depend significantly on incident flux and rotation rate. This provides a way to identify the regime transition in future observations. In some cases, IR light curves can provide constraints on the rotation rate of nonsynchronously rotating planets.

  12. THREE-DIMENSIONAL ATMOSPHERIC CIRCULATION OF WARM AND HOT JUPITERS: EFFECTS OF ORBITAL DISTANCE, ROTATION PERIOD, AND NONSYNCHRONOUS ROTATION

    International Nuclear Information System (INIS)

    Showman, Adam P.; Lewis, Nikole K.; Fortney, Jonathan J.

    2015-01-01

    Efforts to characterize extrasolar giant planet (EGP) atmospheres have so far emphasized planets within 0.05 AU of their stars. Despite this focus, known EGPs populate a continuum of orbital separations from canonical hot Jupiter values (0.03–0.05 AU) out to 1 AU and beyond. Unlike typical hot Jupiters, these more distant EGPs will not generally be synchronously rotating. In anticipation of observations of this population, we here present three-dimensional atmospheric circulation models exploring the dynamics that emerge over a broad range of rotation rates and incident stellar fluxes appropriate for warm and hot Jupiters. We find that the circulation resides in one of two basic regimes. On typical hot Jupiters, the strong day–night heating contrast leads to a broad, fast superrotating (eastward) equatorial jet and large day–night temperature differences. At faster rotation rates and lower incident fluxes, however, the day–night heating gradient becomes less important, and baroclinic instabilities emerge as a dominant player, leading to eastward jets in the midlatitudes, minimal temperature variations in longitude, and, often, weak winds at the equator. Our most rapidly rotating and least irradiated models exhibit similarities to Jupiter and Saturn, illuminating the dynamical continuum between hot Jupiters and the weakly irradiated giant planets of our own solar system. We present infrared (IR) light curves and spectra of these models, which depend significantly on incident flux and rotation rate. This provides a way to identify the regime transition in future observations. In some cases, IR light curves can provide constraints on the rotation rate of nonsynchronously rotating planets

  13. Investigations on the Hot Stamping of AW-7921-T4 Alloy Sheet

    Directory of Open Access Journals (Sweden)

    M. Kumar

    2017-01-01

    Full Text Available AW-7xxx alloys have been nowadays considered for greater light weighting potential in automotive industry due to its higher strength compared to AW-5xxx and AW-6xxx alloys. However, due to their lower formability the forming processes are still in development. This paper investigates one such forming process called hot stamping. The investigation started by carrying out hot tensile testing of an AW-7xxx alloy, that is, AW-7921 at temperatures between 350°C and 475°C, to measure the strength and formability. Formability was found to improve with increasing temperature and was sensitive to the strain rate. Dynamic recovery is considered as usual reason for the formability improvement. However, examining the precipitation states of the as-received condition and after hot stamping using differential scanning calorimetry (DSC, the dissolution of precipitates was also believed to contribute to this increase in formability. Following solution heat treatment there was no precipitation during cooling across the cooling rates investigated (5–10°C/s. Samples taken from parts hot stamped at 10 and 20 mm s−1 had similar yield strengths. A 3-step paint baking heat treatment yielded a higher postpaint baking strength than a single step treatment.

  14. Point kernel technique for calculating dose rates due to cobalt-60 hot particles

    International Nuclear Information System (INIS)

    Thornhill, M.J.; McCarthy, J.T.; Morrissette, R.R.; Leach, B.N.

    1989-01-01

    This paper reports on a computer code called BETA that has been developed by health physicists at the Vermont Yankee Nuclear Power Station which accounts for the mass and size of hot particles of Cobalt-60, and therefore corrects the Loevinger-based dose calculation for self-absorption

  15. Evaluation of a method for assaying sulfonamide antimicrobial residues in cheese: hot-water extraction and liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Berardi, Giorgio; Bogialli, Sara; Curini, Roberta; Di Corcia, Antonio; Laganá, Aldo

    2006-06-28

    Several sulfonamide antimicrobials (SAAs) are largely used in veterinary medicine. A rapid, specific, and sensitive procedure for determining 12 SAAs in cheese is presented. The method is based on the matrix solid-phase dispersion technique followed by liquid chromatography (LC)-tandem mass spectrometry (MS) equipped with an electrospray ion source. Target compounds were extracted from Mozzarella, Asiago, Parmigiano, Emmenthal, and Camembert cheese samples by 6 mL of water modified with 10% methanol and heated at 120 degrees C. The addition of methanol to hot water served to improve remarkably extraction yields of the most lipophilic SAAs, that is, sulfadimethoxine and sulfaquinoxaline. After acidification and filtration, 100 microL of the aqueous extract was injected in the LC column. MS data acquisition was performed in the multireaction monitoring mode, selecting two precursor-to-product ion transitions for each target compound. Methanol-modified hot water appeared to be an efficient extractant, because absolute recovery ranged between 67 and 88%. Using sulfamoxole as surrogate analyte, recovery of the 12 analytes spiked in the five types of cheese considered at the 50 ng/g level ranged between 75 and 105% with RSD not higher than 11%. Statistical analysis of the mean recovery data showed that the extraction efficiency was not affected by the type of cheese analyzed. This result indicates this method could be applied to other cheese types not considered here. The accuracy of the method was determined at three spike levels, that is, 20, 50, and 100 ng/g, and varied between 73 and 102% with relative standard deviations ranging between 4 and 12%. On the basis of a signal-to-noise ratio of 10, limits of quantification were estimated to be <1 ng/g.

  16. Three-dimensional hot electron photovoltaic device with vertically aligned TiO2 nanotubes.

    Science.gov (United States)

    Goddeti, Kalyan C; Lee, Changhwan; Lee, Young Keun; Park, Jeong Young

    2018-05-09

    Titanium dioxide (TiO 2 ) nanotubes with vertically aligned array structures show substantial advantages in solar cells as an electron transport material that offers a large surface area where charges travel linearly along the nanotubes. Integrating this one-dimensional semiconductor material with plasmonic metals to create a three-dimensional plasmonic nanodiode can influence solar energy conversion by utilizing the generated hot electrons. Here, we devised plasmonic Au/TiO 2 and Ag/TiO 2 nanodiode architectures composed of TiO 2 nanotube arrays for enhanced photon absorption, and for the subsequent generation and capture of hot carriers. The photocurrents and incident photon to current conversion efficiencies (IPCE) were obtained as a function of photon energy for hot electron detection. We observed enhanced photocurrents and IPCE using the Ag/TiO 2 nanodiode. The strong plasmonic peaks of the Au and Ag from the IPCE clearly indicate an enhancement of the hot electron flux resulting from the presence of surface plasmons. The calculated electric fields and the corresponding absorbances of the nanodiode using finite-difference time-domain simulation methods are also in good agreement with the experimental results. These results show a unique strategy of combining a hot electron photovoltaic device with a three-dimensional architecture, which has the clear advantages of maximizing light absorption and a metal-semiconductor interface area.

  17. Hot tub folliculitis

    Science.gov (United States)

    ... survives in hot tubs, especially tubs made of wood. Symptoms The first symptom of hot tub folliculitis ... may help prevent the problem. Images Hair follicle anatomy References D'Agata E. Pseudomonas aeruginosa and other ...

  18. Effect of diffraction on stimulated Brillouin scattering from a single laser hot spot

    International Nuclear Information System (INIS)

    Eliseev, V.V.; Rozmus, W.; Tikhonchuk, V.T.; Capjack, C.E.

    1996-01-01

    A single laser hot spot in an underdense plasma is represented as a focused Gaussian laser beam. Stimulated Brillouin scattering (SBS) from such a Gaussian beam with small f/numbers 2-4 has been studied in a three-dimensional slab geometry. It is shown that the SBS reflectivity from a single laser hot spot is much lower than that predicted by a simple three wave coupling model because of the diffraction of the scattered light from the spatially localized ion acoustic wave. SBS gain per one Rayleigh length of the incident laser beam is proposed as a quantitative measure of this effect. Diffraction-limited SBS from a randomized laser beam is also discussed. copyright 1996 American Institute of Physics

  19. Hot and cool executive function in children and adolescents with autism spectrum disorder: Cross-sectional developmental trajectories.

    Science.gov (United States)

    Kouklari, Evangelia-Chrysanthi; Tsermentseli, Stella; Monks, Claire P

    2017-10-20

    The development of executive function (EF) in autism spectrum disorder (ASD) has only been investigated using "cool"-cognitive-EF tasks. Little is known about the development of "hot"-affective-EF and whether it follows a similar developmental pathway. This study employed a cross-sectional developmental trajectories approach to examine the developmental changes in cool (working memory, inhibition, and planning) and hot EF (delay discounting and affective decision-making) of ASD participants (n = 79) and controls (n = 91) relative to age and IQ, shedding more light on the hot-cool EF organization. The developmental trajectories of some aspects of cool EF (working memory and planning) differed significantly as a function of age in ASD participants relative to controls. For both hot EFs, no significant age-related changes were found in either group. These findings extend our understanding regarding the maturation of EF from childhood through adolescence in ASD.

  20. Room temperature nanoindentation creep of hot-pressed B6O

    CSIR Research Space (South Africa)

    Machaka, R

    2014-06-01

    Full Text Available of the nanoindentation creep behavior in B6O ceramics. 1 Room temperature nanoindentation creep of hot-pressed B6O Ronald Machakaa,b,* , Trevor E. Derryb,d, Iakovos Sigalasb,c aLight Metals, Materials Science and Manufacturing, Council for Scientific..., University of the Witwatersrand, Private Bag 3, Wits, Johannesburg 2050, South Africa dSchool of Physics, University of the Witwatersrand, Private Bag 3, Wits, Johannesburg 2050, 2050 South Africa Abstract: Nanoindentation has become a widely...

  1. Leptogenesis. Theory and neutrino masses

    Energy Technology Data Exchange (ETDEWEB)

    Buchmueller, W.

    2012-12-15

    After a brief discussion of baryon and lepton number nonconservation, we review the status of thermal leptogenesis with GUT scale neutrino masses, as well as low scale alternatives with keV neutrinos as dark matter and heavy neutrino masses within the reach of the LHC. Recent progress towards a full quantum mechanical description of leptogenesis is described with resonant leptogenesis as an application. Finally, cosmological B-L breaking after inflation is considered as origin of the hot early universe, generating entropy, baryon asymmetry and dark matter.

  2. Hot subdwarfs formed from the merger of two He white dwarfs

    Science.gov (United States)

    Schwab, Josiah

    2018-06-01

    We perform stellar evolution calculations of the remnant of the merger of two He white dwarfs (WDs). Our initial conditions are taken from hydrodynamic simulations of double WD mergers and the viscous disc phase that follows. We evolve these objects from shortly after the merger into their core He-burning phase, when they appear as hot subdwarf stars. We use our models to quantify the amount of H that survives the merger, finding that it is difficult for ≳ 10^{-4} M_{⊙} of H to survive, with even less being concentrated in the surface layers of the object. We also study the rotational evolution of these merger remnants. We find that mass-loss over the {˜ } 10^4 yr following the merger can significantly reduce the angular momentum of these objects. As hot subdwarfs, our models have moderate surface rotation velocities of 30-100 km s-1. The properties of our models are not representative of many apparently isolated hot subdwarfs, suggesting that those objects may form via other channels or that our modelling is incomplete. However, a sub-population of hot subdwarfs are moderate-to-rapid rotators and/or have He-rich atmospheres. Our models help to connect the observed properties of these objects to their progenitor systems.

  3. Hot conditioning equipment conceptual design report

    International Nuclear Information System (INIS)

    Bradshaw, F.W.

    1996-01-01

    This report documents the conceptual design of the Hot Conditioning System Equipment. The Hot conditioning System will consist of two separate designs: the Hot Conditioning System Equipment; and the Hot Conditioning System Annex. The Hot Conditioning System Equipment Design includes the equipment such as ovens, vacuum pumps, inert gas delivery systems, etc.necessary to condition spent nuclear fuel currently in storage in the K Basins of the Hanford Site. The Hot Conditioning System Annex consists of the facility of house the Hot Conditioning System. The Hot Conditioning System will be housed in an annex to the Canister Storage Building. The Hot Conditioning System will consist of pits in the floor which contain ovens in which the spent nuclear will be conditioned prior to interim storage

  4. Hot conditioning equipment conceptual design report

    Energy Technology Data Exchange (ETDEWEB)

    Bradshaw, F.W., Westinghouse Hanford

    1996-08-06

    This report documents the conceptual design of the Hot Conditioning System Equipment. The Hot conditioning System will consist of two separate designs: the Hot Conditioning System Equipment; and the Hot Conditioning System Annex. The Hot Conditioning System Equipment Design includes the equipment such as ovens, vacuum pumps, inert gas delivery systems, etc.necessary to condition spent nuclear fuel currently in storage in the K Basins of the Hanford Site. The Hot Conditioning System Annex consists of the facility of house the Hot Conditioning System. The Hot Conditioning System will be housed in an annex to the Canister Storage Building. The Hot Conditioning System will consist of pits in the floor which contain ovens in which the spent nuclear will be conditioned prior to interim storage.

  5. Light-ion-induced multifragmentation. A fast, evolutionary process

    International Nuclear Information System (INIS)

    Viola, V.E.; Bracken, D.S.; Foxford, E.R.; Ginger, D.; Kwiatkowski, K.; Morley, K.B.; Hsi, W.C.; Wang, G.; Korteling, R.G.; Legrain, R.

    1996-09-01

    GeV light-ion-induced reactions offer a unique tool for preparing hot, dilute nuclear matter. Time evolution of nuclear multifragmentation in 3 He + nat Ag and 3 He + 197 Au reactions are investigated. Fragment-fragment correlations are studied in order to gain information on multifragmentation mechanism. (K.A.)

  6. On the relationship between tropospheric conditions and widespread hot days in Iran

    Science.gov (United States)

    Asakereh, Hossein; Shadman, Hassan

    2018-01-01

    The present study investigated how the tropospheric conditions relate to the occurrence of widespread hot days (WHD) in Iran using the data of maximum daily temperature and other tropospheric variables. To better understand the tropospheric conditions during WHD, different patterns of tropospheric circulation were examined systematically. Four tropospheric types were identified based on sea level pressure (SLP). SLP, 500 hPa height, anomaly patterns, and warm advection maps were constructed for typical days of each group. The tropospheric conditions associated with hot days occurred simultaneously with a low-pressure system at sea level, a ridge at middle troposphere over Iran, and a pronounced trough over the Mediterranean Sea at 500 hPa. These conditions caused air mass from subtropical regions toward Iran. That is, northward, northeastward, and even eastward winds injected heat with warm origins toward the country. Hot days compounded by drought conditions have affected many parts of the country in different ways such as decrease in the agricultural products in numerous areas and significant discharge reduction in many rivers. The society is also very likely to face considerable challenges to cope with hot days. The findings of the study can be utilized in climate modeling and climate prediction of hot days in the country. Accordingly, water and electricity consumption can be planned with further precision and water consumption can be managed in crises.

  7. Analysis of chemical degradation mechanism of phosphorescent organic light emitting devices by laser-desorption/ionization time-of-flight mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Rabelo de Moraes, Ines; Scholz, Sebastian; Luessem, Bjoern; Leo, Karl [Institut fuer Angewandte Photophysik, Technische Universitaet Dresden (Germany)

    2010-07-01

    Phosphorescent organic light emitting diodes (OLEDs) have attracted much interest for their potential application in full color flat-panel displays and as an alternative lighting source. However, low efficiency, and the short operation lifetime, in particular in the case of blue emitting devices, are the major limitations for the current OLEDs commercialization. In order to overcome these limitations, a deep knowledge about the aging and the degradation mechanism is required. Our work focuses on the chemical degradation mechanism of different iridium based emitter materials like FIrpic (light blue) and Ir(ppy)3 (green), commonly used in OLEDs. For this purpose, the devices were aged by electrical driving until the luminance reached 6% of the initial luminance. The laser-desorption/ionization time-of-flight mass spectrometry was used to determine specific degradation pathways.

  8. Hot helium flow test facility summary report

    International Nuclear Information System (INIS)

    1980-06-01

    This report summarizes the results of a study conducted to assess the feasibility and cost of modifying an existing circulator test facility (CTF) at General Atomic Company (GA). The CTF originally was built to test the Delmarva Power and Light Co. steam-driven circulator. This circulator, as modified, could provide a source of hot, pressurized helium for high-temperature gas-cooled reactor (HTGR) and gas-cooled fast breeder reactor (GCFR) component testing. To achieve this purpose, a high-temperature impeller would be installed on the existing machine. The projected range of tests which could be conducted for the project is also presented, along with corresponding cost considerations

  9. Light water detritiation

    Energy Technology Data Exchange (ETDEWEB)

    Fedorchenko, O.A.; Aleksee, I.A.; Bondarenko, S.D.; Vasyanina, T.V. [B.P. Konstantinov Petersburg Nuclear Physics Institute of National Research Centre ' Kurchatov Institute' , Gatchina (Russian Federation)

    2015-03-15

    Hundreds of thousands of tons of tritiated light water have been accumulating from the enterprises of nuclear fuel cycles around the world. The Dual-Temperature Water-Hydrogen (DTWH) process looks like the only practical alternative to Combined Electrolysis and Catalytic Exchange (CECE). In DTWH power-consuming lower reflux device (electrolytic cell) is replaced by a so-called 'hot tower' (LPCE column operating at conditions which ensure relatively small value of elementary separation factor α(hot)). In the upper, cold tower, the tritium transfers from hydrogen to water while in the lower, hot tower - in the opposite direction - from water to hydrogen. The DTWH process is much more complicated compared to CECE; it must be thoroughly computed and strictly controlled by an automatic control system. The use of a simulation code for DTWH is absolutely important. The simulation code EVIO-5 deals with 3 flows inside a column (hydrogen gas, water vapour and liquid water) and 2 simultaneous isotope exchange sub-processes (counter-current phase exchange and co-current catalytic exchange). EVIO-5 takes into account the strong dependence of process performance on given conditions (temperature and pressure). It calculates steady-state isotope concentration profiles considering a full set of reversible exchange reactions between different isotope modifications of water and hydrogen (12 molecular species). So the code can be used for simulation of LPCE column operation for detritiation of hydrogen and water feed, which contains H and D not only at low concentrations but above 10 at.% also. EVIO-5 code is used to model a Tritium Removal Facility with a throughput capacity of about 400 m{sup 3}/day. Simulation results show that a huge amount of wet-proofed catalyst is required (about 6000 m{sup 3}), mainly (90%) in the first stage. One reason for these large expenses (apart from a big scale of the problem itself) is the relatively high tritium separation factor in the

  10. Light water detritiation

    International Nuclear Information System (INIS)

    Fedorchenko, O.A.; Aleksee, I.A.; Bondarenko, S.D.; Vasyanina, T.V.

    2015-01-01

    Hundreds of thousands of tons of tritiated light water have been accumulating from the enterprises of nuclear fuel cycles around the world. The Dual-Temperature Water-Hydrogen (DTWH) process looks like the only practical alternative to Combined Electrolysis and Catalytic Exchange (CECE). In DTWH power-consuming lower reflux device (electrolytic cell) is replaced by a so-called 'hot tower' (LPCE column operating at conditions which ensure relatively small value of elementary separation factor α(hot)). In the upper, cold tower, the tritium transfers from hydrogen to water while in the lower, hot tower - in the opposite direction - from water to hydrogen. The DTWH process is much more complicated compared to CECE; it must be thoroughly computed and strictly controlled by an automatic control system. The use of a simulation code for DTWH is absolutely important. The simulation code EVIO-5 deals with 3 flows inside a column (hydrogen gas, water vapour and liquid water) and 2 simultaneous isotope exchange sub-processes (counter-current phase exchange and co-current catalytic exchange). EVIO-5 takes into account the strong dependence of process performance on given conditions (temperature and pressure). It calculates steady-state isotope concentration profiles considering a full set of reversible exchange reactions between different isotope modifications of water and hydrogen (12 molecular species). So the code can be used for simulation of LPCE column operation for detritiation of hydrogen and water feed, which contains H and D not only at low concentrations but above 10 at.% also. EVIO-5 code is used to model a Tritium Removal Facility with a throughput capacity of about 400 m 3 /day. Simulation results show that a huge amount of wet-proofed catalyst is required (about 6000 m 3 ), mainly (90%) in the first stage. One reason for these large expenses (apart from a big scale of the problem itself) is the relatively high tritium separation factor in the hot tower

  11. HOT GAS HALOS AROUND DISK GALAXIES: CONFRONTING COSMOLOGICAL SIMULATIONS WITH OBSERVATIONS

    International Nuclear Information System (INIS)

    Rasmussen, Jesper; Sommer-Larsen, Jesper; Pedersen, Kristian; Toft, Sune; Grove, Lisbeth F.; Benson, Andrew; Bower, Richard G.

    2009-01-01

    Models of disk galaxy formation commonly predict the existence of an extended reservoir of accreted hot gas surrounding massive spirals at low redshift. As a test of these models, we use X-ray and Hα data of the two massive, quiescent edge-on spirals NGC 5746 and NGC 5170 to investigate the amount and origin of any hot gas in their halos. Contrary to our earlier claim, the Chandra analysis of NGC 5746, employing more recent calibration data, does not reveal any significant evidence for diffuse X-ray emission outside the optical disk, with a 3σ upper limit to the halo X-ray luminosity of 4 x 10 39 erg s -1 . An identical study of the less massive NGC 5170 also fails to detect any extraplanar X-ray emission. By extracting hot halo properties of disk galaxies formed in cosmological hydrodynamical simulations, we compare these results to expectations for cosmological accretion of hot gas by spirals. For Milky-Way-sized galaxies, these high-resolution simulations predict hot halo X-ray luminosities which are lower by a factor of ∼2 compared to our earlier results reported by Toft et al. We find the new simulation predictions to be consistent with our observational constraints for both NGC 5746 and NGC 5170, while also confirming that the hot gas detected so far around more actively star-forming spirals is in general probably associated with stellar activity in the disk. Observational results on quiescent disk galaxies at the high-mass end are nevertheless providing powerful constraints on theoretical predictions, and hence on the assumed input physics in numerical studies of disk galaxy formation and evolution.

  12. Light charged particle emission in the matched reactions 280 MeV 40Ar+27Al and 670 MeV 55Mn+12C: Inclusive studies

    International Nuclear Information System (INIS)

    Brown, Craig M.; Milosevich, Zoran; Kaplan, Morton; Vardaci, Emanuele; DeYoung, Paul; Whitfield, James P.; Peterson, Donald; Dykstra, Christopher; Karol, Paul J.; McMahan, Margaret A.

    1999-01-01

    In order to test the statistical model's ability to predict the behavior of relatively light mass systems (A≅67) with large angular momenta, two matched heavy ion nuclear reactions were used to produce 67 Ga * composite nuclei at an excitation energy of 127 MeV. Light charged particles (protons, deuterons, tritons, and α particles) were used as probes to characterize the composite systems and track the deexcitation processes. From these measurements, energy spectra, cross sections, angular distributions, anisotropy ratios, and particle multiplicities were deduced. Measuring many degrees of freedom provides a stringent test for the statistical models. What is found is that models which did well in predicting the behavior of heavy composite systems (A≅150), are unable to simultaneously reproduce energy spectra, angular distributions, and particle multiplicities for the lighter systems (A≅67), where angular momentum plays a dominant role. This implies that more rigorous models and/or additional physics are needed to understand the behavior of the hot, high-spin nuclear matter in this mass region. (c) 1999 The American Physical Society

  13. Photoelectic BV Light Curves of Algol and the Interpretations of the Light Curves

    Directory of Open Access Journals (Sweden)

    Ho-Il Kim

    1985-06-01

    Full Text Available Standardized B and V photoelectric light curves of Algol are made with the observations obtained during 1982-84 with the 40-cm and the 61-cm reflectors of Yonsei University Observatory. These light curves show asymmetry between ascending and descending shoulders. The ascending shoulder is 0.02 mag brighter than descending shoulder in V light curve and 0.03 mag in B light curve. These asymmetric light curves are interpreted as the result of inhomogeneous energy distribution on the surface of one star of the eclipsing pair rather than the result of gaseous stream flowing from KOIV to B8V star. The 180-year periodicity, so called great inequality, are most likely the result proposed by Kim et al. (1983 that the abrupt and discrete mass losses of cooler component may be the cause of this orbital change. The amount of mass loss deduced from these discrete period changes turned out to be of the order of 10^(-6 - 10^(-5 Msolar.

  14. Origin of the hot gas in low-mass protostars

    DEFF Research Database (Denmark)

    Van Kempen, T. A.; Kristensen, L. E.; Herczeg, G. J.

    2010-01-01

    Aims. "Water In Star-forming regions with Herschel" (WISH) is a Herschel key programme aimed at understanding the physical and chemical structure of young stellar objects (YSOs) with a focus on water and related species. Methods. The low-mass protostar HH 46 was observed with the Photodetector Ar...

  15. Cross-correlation of the cosmic microwave background with the 2MASS galaxy survey: Signatures of dark energy, hot gas, and point sources

    International Nuclear Information System (INIS)

    Afshordi, Niayesh; Loh, Yeong-Shang; Strauss, Michael A.

    2004-01-01

    We cross-correlate the cosmic microwave background temperature anisotropies observed by the Wilkinson Microwave Anisotropy Probe (WMAP) with the projected distribution of extended sources in the Two Micron All Sky Survey (2MASS). By modeling the theoretical expectation for this signal, we extract the signatures of dark energy [integrated Sachs-Wolfe effect (ISW)], hot gas [thermal Sunyaev-Zeldovich (SZ) effect], and microwave point sources in the cross-correlation. Our strongest signal is the thermal SZ, at the 3.1-3.7σ level, which is consistent with the theoretical prediction based on observations of x-ray clusters. We also see the ISW signal at the 2.5σ level, which is consistent with the expected value for the concordance ΛCDM cosmology, and is an independent signature of the presence of dark energy in the Universe. Finally, we see the signature of microwave point sources at the 2.7σ level

  16. Hot water extracted wood fiber for production of wood plastic composites (WPCs)

    Science.gov (United States)

    Manuel Raul Pelaez-Samaniego; Vikram Yadama; Eini Lowell; Thomas E. Amidon; Timothy L. Chaffee

    2013-01-01

    Undebarked ponderosa pine chips were treated by hot water extraction to modify the chemical composition. In the treated pine (TP) , the mass was reduced by approximately 20%, and the extract was composed mainly of degradation products of hemicelluloses. Wood flour produced from TP and unextracted chips (untreated pine, UP) was blended with high-density polyethylene (...

  17. Hot water in the Inner 100 AU of the Class 0 protostar NGC 1333 IRAS2A

    DEFF Research Database (Denmark)

    Visser, Ruud; Jørgensen, Jes Kristian; Kristensen, Lars E.

    2013-01-01

    -303 lines of H_2^{16}O and H_2^{18}O (1097 GHz, E u/k = 249 K) in the low-mass Class 0 protostar NGC 1333 IRAS2A. A spherical radiative transfer model with a power-law density profile is unable to reproduce both the HIFI data and existing interferometric data on the H_2^{18}O 313-220 line (203 GHz, E u....../k = 204 K). Instead, the HIFI spectra likely show optically thick emission from a hot core with a radius of about 100 AU. The mass of the hot core is estimated from the C18O J = 9-8 and 10-9 lines. We derive a lower limit to the hot water abundance of 2 × 10-5, consistent with the theoretical predictions...... of ~10-4. The revised HDO/H2O abundance ratio is 1 × 10-3, an order of magnitude lower than previously estimated. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA....

  18. Light--light scattering tensor and the anomalous magnetic moment of the muon

    International Nuclear Information System (INIS)

    Kuraev, E.A.; Silagadze, Z.K.; Cheshel', A.A.; Schiller, A.

    1989-01-01

    A general expression is obtained for the tensor that describes the effect of light--light scattering on the anomalous magnetic moment of leptons. An explicit expression is derived for the electron-loop contribution, for which an analytic evaluation is carried out of the coefficient in front of the logarithm of the ratio of the muon mass to the electron mass in the anomalous magnetic moment of the muon. Logarithmic contributions due to radiative corrections are shown to originate exclusively from the inclusion of the polarization of the vacuum of virtual photons

  19. UPTF-TRAM test A3. Turn-over of the hot-leg injected ECC in the steam generator direction

    International Nuclear Information System (INIS)

    Tenckhoff; Brand, B.; Weiss, P.

    1993-06-01

    The UPTF TRAM test A3 was a separate effects test to investigate the interaction between the hot leg-injected ECC and the single-phase or two-phase natural circulation in the hot leg in the case of an SBLOCA in a PWR. The experimental investigation of 7 runs was mainly concentrated on the following phenomena: - Transport of hot leg injected ECC water to the upper plenum or in the direction of steam generator, depending on the loop mass flow, -Utilization of the condensation potential of ECC water, - Mixing of the saturated water with the ECC water, - Effect of hot leg injection on the flow phenomena in the hot leg, - Effect of pressure (3 and 15 bar) on the scaling and hence the verification of the scaling concept applied. A preliminary evaluation of the test is presented in the Quick Look Report. (orig.) [de

  20. Confining hot spots in 3C 196 - implications for QSO-companion galaxies

    International Nuclear Information System (INIS)

    Brown, R.L.; Broderick, J.J.; Mitchell, K.J.; Virginia Polytechnic Institute and State Univ., Blacksburg; NASA, Goddard Space Flight Center, Greenbelt, MD)

    1986-01-01

    VLBI observations of the extremely compact hot spot in the northern radio lobe of the QSO 3C 196 reveal the angular size of its smallest substructure to be 0.065 arcsec x 0.045 arcsec or about 300 pc at the redshift distance. The morphology of the hot spot and its orientation relative to the more diffuse radio emission suggest that it is formed by an oblique interaction between the nuclear QSO jet and circum-QSO cloud. The inferred density in this cloud, together with its apparent size, imply that the cloud contains a galactic mass, greater than a billion solar masses of gas. The effect of the jet will be to hasten gravitational collapse of the cloud. If many QSOs such as 3C 196 are formed or found in gas-rich environments, the QSO radio phase may commonly stimulate the metamorphosis of circum-QSO gas to QSO-companion galaxies or it may play a significant part in catalyzing star formation in existing companions. 30 references

  1. A Metabolomics-Guided Exploration of the Phytochemical Constituents of Vernonia fastigiata with the Aid of Pressurized Hot Water Extraction and Liquid Chromatography-Mass Spectrometry.

    Science.gov (United States)

    Masike, Keabetswe; Khoza, Bradley S; Steenkamp, Paul A; Smit, Elize; Dubery, Ian A; Madala, Ntakadzeni E

    2017-07-27

    Vernonia fastigiata is a multi-purpose nutraceutical plant with interesting biological properties. However, very little is known about its phytochemical composition and, thus the need for its phytochemical characterization. In the current study, an environmentally friendly method, pressurized hot water extraction (PHWE), was used to extract metabolites from the leaves of V. fastigiata at various temperatures (50 °C, 100 °C, 150 °C and 200 °C). Ultra-high performance liquid chromatography-quadrupole time of flight mass spectrometry (UHPLC-qTOF-MS) analysis in combination with chemometric methods, particularly principal component analysis (PCA) and liquid/gas chromatography mass spectrometry (XCMS) cloud plots, were used to descriptively visualize the data and identify significant metabolites extracted at various temperatures. A total of 25 different metabolites, including hydroxycinnamic acid derivatives, clovamide, deoxy-clovamide and flavonoids, were noted for the first time in this plant. Overall, an increase in extraction temperature resulted in an increase in metabolite extraction during PHWE. This study is the first scientific report on the phytochemical composition of V. fastigiata , providing insight into the components of the chemo-diversity of this important plant.

  2. Shadow of a Large Disc Casts New Light on the Formation of High Mass Stars

    Science.gov (United States)

    2004-05-01

    : 3815 x 4574 pix - 5.4M] Caption: PR Photo 15a/04 is a reproduction of a three-colour composite of the sky region of M 17, a H II region excited by a cluster of young, hot stars. A large silhouette disc has been found to the south-west of the cluster centre. The area within the indicated square is shown in more detail in PR Photo 15b/04. The present image was obtained with the ISAAC near-infrared instrument at the 8.2-m VLT ANTU telescope at Paranal. In the left photo, the orientation and the scale at the distance of M 17 (7,000 light-years) are indicated, and the main regions are identified. To the right, this beautiful photo is available without text and in full resolution for reproduction purposes. While many details related to the formation and early evolution of low-mass stars like the Sun are now well understood, the basic scenario that leads to the formation of high-mass stars [2] still remains a mystery. Two possible scenarios for the formation of massive stars are currently being studied. In the first, such stars form by accretion of large amounts of circumstellar material; the infall onto the nascent star varies with time. Another possibility is formation by collision (coalescence) of protostars of intermediate masses, increasing the stellar mass in "jumps". In their continuing quest to add more pieces to the puzzle and help providing an answer to this fundamental question, a team of European astronomers [1] used a battery of telescopes, mostly at two of the European Southern Observatory's Chilean sites of La Silla and Paranal, to study in unsurpassed detail the Omega nebula. The Omega nebula, also known as the 17th object in the list of famous French astronomer Charles Messier, i.e. Messier 17 or M 17, is one of the most prominent star forming regions in our Galaxy. It is located at a distance of 7,000 light-years. M 17 is extremely young - in astronomical terms - as witnessed by the presence of a cluster of high-mass stars that ionise the surrounding

  3. Examining variation in the leaf mass per area of dominant species across two contrasting tropical gradients in light of community assembly

    NARCIS (Netherlands)

    Neyret, Margot; Bentley, Lisa Patrick; Oliveras Menor, Imma; Marimon, Beatriz S.; Marimon-Junior, Ben Hur; Almeida de Oliveira, Edmar; Barbosa Passos, Fábio; Castro Ccoscco, Rosa; Santos, dos Josias; Matias Reis, Simone; Morandi, Paulo S.; Rayme Paucar, Gloria; Robles Cáceres, Arturo; Valdez Tejeira, Yolvi; Yllanes Choque, Yovana; Salinas, Norma; Shenkin, Alexander; Asner, Gregory P.; Díaz, Sandra; Enquist, Brian J.; Malhi, Yadvinder

    2016-01-01

    Understanding variation in key functional traits across gradients in high diversity systems and the ecology of community changes along gradients in these systems is crucial in light of conservation and climate change. We examined inter- and intraspecific variation in leaf mass per area (LMA) of

  4. First Direct Mass Measurements of Nuclides around Z =100 with a Multireflection Time-of-Flight Mass Spectrograph

    Science.gov (United States)

    Ito, Y.; Schury, P.; Wada, M.; Arai, F.; Haba, H.; Hirayama, Y.; Ishizawa, S.; Kaji, D.; Kimura, S.; Koura, H.; MacCormick, M.; Miyatake, H.; Moon, J. Y.; Morimoto, K.; Morita, K.; Mukai, M.; Murray, I.; Niwase, T.; Okada, K.; Ozawa, A.; Rosenbusch, M.; Takamine, A.; Tanaka, T.; Watanabe, Y. X.; Wollnik, H.; Yamaki, S.

    2018-04-01

    The masses of 246Es, 251Fm, and the transfermium nuclei Md-252249 and 254No, produced by hot- and cold-fusion reactions, in the vicinity of the deformed N =152 neutron shell closure, have been directly measured using a multireflection time-of-flight mass spectrograph. The masses of 246Es and 249,250,252Md were measured for the first time. Using the masses of Md,250249 as anchor points for α decay chains, the masses of heavier nuclei, up to 261Bh and 266Mt, were determined. These new masses were compared with theoretical global mass models and demonstrated to be in good agreement with macroscopic-microscopic models in this region. The empirical shell gap parameter δ2 n derived from three isotopic masses was updated with the new masses and corroborates the existence of the deformed N =152 neutron shell closure for Md and Lr.

  5. A Composite Light Curve Model of the Symbiotic Nova PU Vul (1979

    Directory of Open Access Journals (Sweden)

    Kato M.

    2012-06-01

    Full Text Available PU Vul (1979 is a symbiotic nova that shows a long-lasting flat optical peak followed by a slow decline. We made a quasi-evolution model for outbursts on a 0.6 M⊙ white dwarf consisting of a series of static solutions with optically-thin winds. Our theoretical models reproduce well the observed visual/UV light curves as well as the new estimates of the temperature and radius of the hot component. We also modeled the light curve of the 1980 and 1994 eclipses as the total eclipse occulted by a pulsating M-giant companion star. In the second eclipse, the visual magnitude is dominated by nebular emission which is possibly ejected from the hot component between 1990 to 2000. We have quantitatively estimated three components of emission, i.e., the white dwarf, companion and nebular, and made a composite light curve that represents well the evolution of the PU Vul outburst.

  6. A naturally light Higgs without light Top Partners

    CERN Document Server

    Carmona, Adrian

    2015-01-01

    We demonstrate that the inclusion of a realistic lepton sector can relax significantly the upper bound on top partner masses in minimal composite Higgs models, induced by the lightness of the Higgs boson. To that extend, we present a comprehensive survey of the impact of different realizations of the fermion sectors on the Higgs potential, with a special emphasis on the role of the leptons. The non-negligible compositeness of the $\\tau_R$ in a general class of models that address the flavor structure of the lepton sector and the smallness of the corresponding FCNCs, can have a significant effect on the potential. We find that, with the $\\tau_R$ in the symmetric representation of $SO(5)$, an increase in the maximally allowed mass of the lightest top partner of $\\gtrsim 1$ TeV is possible for minimal quark setups like the MCHM$_{5,10}$, without increasing the tuning. A light Higgs boson $m_H \\sim(100-200)$ GeV is a natural prediction of such models, which thus provide a new setup that can evade ultra-light top ...

  7. Entrance channel influence on the formation and decay of hot nuclei

    International Nuclear Information System (INIS)

    Harar, S.

    1987-04-01

    Different entrance channels have been investigated to form very hot nuclei and to study their decay properties. i) Argon and Nickel projectiles accelerated around the Fermi energy show that central collisions induce momentum transfers to target nuclei which are proportional to the mass of the projectile and not to its velocities in the studied energy range. The preequilibrium model fits nicely the experimental results. The decay properties of the fission products for hot nuclei will be presented. Both head-on collisions and peripheral massive transfers contribute to the formation of very excited nuclei. The question of the influence of the energy deposit in the composite like system in limiting their yields is discussed. ii) Investigations have been also achieved with alpha projectiles at much higher incident energy (around 1 GeV/u). It is shown that hot and thermalized nuclei are also formed even when the nucleon-nucleon collisions are predominant. A sensitive parameter of the transition from binary fission to multifragmentation seems to be the energy deposit in the target residues rather than the projectile velocity

  8. Supersymmetry across the light and heavy-light hadronic spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Dosch, Hans Gunter [Institut fur Theoretische Physik, Heidelberg (Germany); de Teramond, Guy F. [Univ. de Costa Rica, San Pedro de Montes de Oca (Costa Rica); Brodsky, Stanley J. [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-10-07

    Relativistic light-front bound-state equations for mesons and baryons can be constructed in the chiral limit from the supercharges of a superconformal algebra which connect baryon and meson spectra. Quark masses break the conformal invariance, but the basic underlying supersymmetric mechanism, which transforms meson and baryon wave functions into each other, still holds and gives remarkable connections across the entire spectrum of light and heavy-light hadrons. As a result, we also briefly examine the consequences of extending the supersymmetric relations to double-heavy mesons and baryons.

  9. WESF hot cells waste minimization criteria hot cells window seals evaluation

    International Nuclear Information System (INIS)

    Walterskirchen, K.M.

    1997-01-01

    WESF will decouple from B Plant in the near future. WESF is attempting to minimize the contaminated solid waste in their hot cells and utilize B Plant to receive the waste before decoupling. WESF wishes to determine the minimum amount of contaminated waste that must be removed in order to allow minimum maintenance of the hot cells when they are placed in ''laid-up'' configuration. The remaining waste should not cause unacceptable window seal deterioration for the remaining life of the hot cells. This report investigates and analyzes the seal conditions and hot cell history and concludes that WESF should remove existing point sources, replace cerium window seals in F-Cell and refurbish all leaded windows (except for A-Cell). Work should be accomplished as soon as possible and at least within the next three years

  10. 10 CFR 431.102 - Definitions concerning commercial water heaters, hot water supply boilers, and unfired hot water...

    Science.gov (United States)

    2010-01-01

    ... supply boilers, and unfired hot water storage tanks. 431.102 Section 431.102 Energy DEPARTMENT OF ENERGY... Water Heaters, Hot Water Supply Boilers and Unfired Hot Water Storage Tanks § 431.102 Definitions concerning commercial water heaters, hot water supply boilers, and unfired hot water storage tanks. The...

  11. FRIENDS OF HOT JUPITERS. II. NO CORRESPONDENCE BETWEEN HOT-JUPITER SPIN-ORBIT MISALIGNMENT AND THE INCIDENCE OF DIRECTLY IMAGED STELLAR COMPANIONS

    Energy Technology Data Exchange (ETDEWEB)

    Ngo, Henry; Knutson, Heather A.; Hinkley, Sasha; Batygin, Konstantin [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA (United States); Crepp, Justin R.; Bechter, Eric B. [Department of Physics, University of Notre Dame, Notre Dame, IN (United States); Howard, Andrew W. [Institute for Astronomy, University of Hawaii at Manoa, Honolulu, HI (United States); Johnson, John A. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Morton, Timothy D. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA (United States); Muirhead, Philip S., E-mail: hngo@caltech.edu [Department of Astronomy, Boston University, Boston, MA (United States)

    2015-02-20

    Multi-star systems are common, yet little is known about a stellar companion's influence on the formation and evolution of planetary systems. For instance, stellar companions may have facilitated the inward migration of hot Jupiters toward to their present day positions. Many observed short-period gas giant planets also have orbits that are misaligned with respect to their star's spin axis, which has also been attributed to the presence of a massive outer companion on a non-coplanar orbit. We present the results of a multi-band direct imaging survey using Keck NIRC2 to measure the fraction of short-period gas giant planets found in multi-star systems. Over three years, we completed a survey of 50 targets ('Friends of Hot Jupiters') with 27 targets showing some signature of multi-body interaction (misaligned or eccentric orbits) and 23 targets in a control sample (well-aligned and circular orbits). We report the masses, projected separations, and confirmed common proper motion for the 19 stellar companions found around 17 stars. Correcting for survey incompleteness, we report companion fractions of 48% ± 9%, 47% ± 12%, and 51% ± 13% in our total, misaligned/eccentric, and control samples, respectively. This total stellar companion fraction is 2.8σ larger than the fraction of field stars with companions approximately 50-2000 AU. We observe no correlation between misaligned/eccentric hot Jupiter systems and the incidence of stellar companions. Combining this result with our previous radial velocity survey, we determine that 72% ± 16% of hot Jupiters are part of multi-planet and/or multi-star systems.

  12. Progress in light cone physics

    International Nuclear Information System (INIS)

    Preparata, G.

    1973-01-01

    A very brief review is given of the progress made in the physics of the light cone in the past year. Included are the light cone expansion, gauge invariance and the consequences of precocious scaling near threshold, the light cone description of the muon pair experiment, light cone expansions, and the assessment and exploitation of analyticity properties in both mass and energy of light cone amplitudes. (U.S.)

  13. Measurement of light charged particles in the decay channels of medium-mass excited compound nuclei

    Directory of Open Access Journals (Sweden)

    Valdré S.

    2014-03-01

    Indeed, in this mass region (A ~ 100 models predict that shape transitions can occur at high spin values and relatively scarce data exist in the literature about coincidence measurements between evaporation residues and light charged particles. Signals of shape transitions can be found in the variations of the lineshape of high energy gamma rays emitted from the de-excitation of GDR states gated on different region of angular momenta. For this purpose it is important to keep under control the FE and FF processes, to regulate the statistical model parameters and to control the onset of possible pre-equilibrium emissions from 300 to 600 MeV bombarding energy.

  14. A see-saw mechanism with light sterile neutrinos

    International Nuclear Information System (INIS)

    McKellar, B.H.J.; Garbutt, M.; Stephenson, G.J.; Goldman, T.

    2001-01-01

    The usual see-saw mechanism for the generation of light neutrino masses is based on the assumption that all of the flavours of right-handed (more properly, sterile) neutrinos are heavy. If the sterile Majorana mass matrix is singular, one or more of the sterile neutrinos will have zero mass before mixing with the active (left-handed) neutrinos and be light after that mixing is introduced In particular, a rank 1 sterile mass matrix leads naturally to two pseudo-Dirac pairs, one very light active Majorana neutrino and one heavy sterile Majorana neutrino. For any pattern of Dirac masses, there exists a region of parameter space in which the two pseudo-Dirac pairs are nearly degenerate in mass. This, in turn, leads to large amplitude mixing of active states as well as mixing into sterile states

  15. High Throughput, High Precision Hot Testing Tool for HBLED Wafer Level Testing

    Energy Technology Data Exchange (ETDEWEB)

    Solarz, Richard [KLA-Tencor Corporation, Milpitas, CA (United States); McCord, Mark [KLA-Tencor Corporation, Milpitas, CA (United States)

    2015-12-31

    The Socrates research effort developed an in depth understanding and demonstrated in a prototype tool new precise methods for teh characterization of color characteristics and flux from individual LEDs for the production of uniform quality lighting. This effort was focused on improving the color quality and consistency of solid state lighting and potentially reducing characterization costs for all LED product types. The patented laser hot testing method was demonstrated to be far more accurate than all current state of the art color and flux characterization methods in use by the solid state lighting industry today. A seperately patented LED grouping method (statistical binning) was demonstrated to be a useful approach to improving utilization of entire lots of large color and flux distributions of manufactured LEDs for high quality color solid-state lighting. At the conclusion of the research in late 2015 the solid-state lighting industry was however generally satisfied with its existing production methods for high quality color products for the small segment of customers that demand it, albeit with added costs.

  16. The Effects of Simulated Wildland Firefighting Tasks on Core Temperature and Cognitive Function under Very Hot Conditions

    Directory of Open Access Journals (Sweden)

    F. Michael Williams-Bell

    2017-10-01

    Full Text Available Background: The severity of wildland fires is increasing due to continually hotter and drier summers. Firefighters are required to make life altering decisions on the fireground, which requires analytical thinking, problem solving, and situational awareness. This study aimed to determine the effects of very hot (45°C; HOT conditions on cognitive function following periods of simulated wildfire suppression work when compared to a temperate environment (18°C; CON.Methods: Ten male volunteer firefighters intermittently performed a simulated fireground task for 3 h in both the CON and HOT environments, with cognitive function tests (paired associates learning and spatial span assessed at baseline (cog 1 and during the final 20-min of each hour (cog 2, 3, and 4. Reaction time was also assessed at cog 1 and cog 4. Pre- and post- body mass were recorded, and core and skin temperature were measured continuously throughout the protocol.Results: There were no differences between the CON and HOT trials for any of the cognitive assessments, regardless of complexity. While core temperature reached 38.7°C in the HOT (compared to only 37.5°C in the CON; p < 0.01, core temperature declined during the cognitive assessments in both conditions (at a rate of −0.15 ± 0.20°C·hr−1 and −0.63 ± 0.12°C·hr−1 in the HOT and CON trial respectively. Firefighters also maintained their pre-exercise body mass in both conditions, indicating euhydration.Conclusions: It is likely that this maintenance of euhydration and the relative drop in core temperature experienced between physical work bouts was responsible for the preservation of firefighters' cognitive function in the present study.

  17. Hot subluminous stars: On the Search for Chemical Signatures of their Genesis

    Science.gov (United States)

    Hirsch, Heiko Andreas

    2009-10-01

    This thesis deals with the hot subluminous stars of spectral class O. Although the name suggests otherwise, these stars are still 10 to 1000 times more luminous than the sun, they emit most of their radiation energy in the ultraviolet range. First stars of this type have been categorized in the 1950ies. Since they are blue objects like Quasars they often are discovered in surveys at high Galactic latitudes aiming at Quasars and other extragalactic objects. The hot subluminous stars can be divided into two classes, the subluminous O and subluminous B stars, or short sdO and sdB. The sdOs and sdBs play an important role in astronomy, as many old stellar populations, e.g. globular clusters and elliptical galaxies, have strong UV fluxes. UV bright regions often are "stellar nurseries", where new stars are born. Globular clusters and elliptical galaxies, however, do not experience star formation. This UV excess can be explained by population models that include the hot subluminous stars. Many sdB stars show short-period, multiperiodic light variations, which are due to radial and nonradial pulsations. Asteroseismology can explore the inner structure of stars and estimate e.g. the stellar mass, a variable that can only determine in very lucky circumstances (eclipsing binaries). These stars are also important for cosmology because they qualify as supernova Ia progenitors. The nature of the sdO stars is less well understood than that of their cooler and more numerous siblings, the sdBs. The connection of the sdBs to the horizontal branch is established for many years now, accordingly they are old helium core burning objects after their red giant phase. More precisely, they are on the extended horizontal branch (EHB), the hot end of the horizontal branch. EHB stars are characterized by a very low envelope mass, i.e. we see more or less directly the hot helium burning core. Strong mass loss in the RGB phase is regarded as responsible for this phenomenon, the exact mechanism

  18. Light extinction by fine atmospheric particles in the White Mountains region of New Hampshire and its relationship to air mass transport.

    Science.gov (United States)

    Slater, John F; Dibb, Jack E; Keim, Barry D; Talbot, Robert W

    2002-03-27

    Chemical, optical, and physical measurements of fine aerosols (aerodynamic diameter mass origin. Filter-based, 24-h integrated samples were collected and analyzed for major inorganic ions, as well as organic (OC), elemental (EC), and total carbon. Light scattering and light absorption coefficients were measured at 5-min intervals using an integrating nephelometer and a light absorption photometer. Fine particle number density was measured with a condensation particle counter. Air mass origins and transport patterns were investigated through the use of 3-day backward trajectories and a synoptic climate classification system. Two distinct transport regimes were observed: (1) flow from the north/northeast (N/NE) occurred during 9 out of 18 sample-days; and (2) flow from the west/southwest (W/SW) occurred 8 out of 18 sample-days. All measured and derived aerosol and meteorological parameters were separated into two categories based on these different flow scenarios. During W/SW flow, higher values of aerosol chemical concentration, absorption and scattering coefficients, number density, and haziness were observed compared to N/NE flow. The highest level of haziness was associated with the climate classification Frontal Atlantic Return, which brought polluted air into the region from the mid-Atlantic corridor. Fine particle mass scattering efficiencies of (NH4)2SO4 and OC were 5.35 +/- 0.42 m2 g(-1) and 1.56 +/- 0.40 m2 g(-1), respectively, when transport was out of the N/NE. When transport was from the W/SW the values were 4.94 +/- 0.68 m2 g(-1) for (NH4)2SO4 and 2.18 +/- 0.91 m2 g(-1) for OC. EC mass absorption efficiency when transport was from the N/NE was 9.66 +/- 1.06 m2 g(-1) and 10.80 +/- 1.76 m2 g(-1) when transport was from the W/SW. Results from this work can be used to predict visual air quality in the White Mountain National Forest based on a forecasted synoptic climate classification and its associated visibility.

  19. News on the X-ray emission from hot subdwarf stars

    Directory of Open Access Journals (Sweden)

    Palombara Nicola La

    2017-12-01

    Full Text Available In latest years, the high sensitivity of the instruments on-board the XMM-Newton and Chandra satellites allowed us to explore the properties of the X-ray emission from hot subdwarf stars. The small but growing sample of X-ray detected hot subdwarfs includes binary systems, in which the X-ray emission is due to wind accretion onto a compact companion (white dwarf or neutron star, as well as isolated sdO stars, in which X-rays are probably due to shock instabilities in the wind. X-ray observations of these low-mass stars provide information which can be useful for our understanding of the weak winds of this type of stars and can lead to the discovery of particularly interesting binary systems. Here we report the most recent results we have recently obtained in this research area.

  20. THE MASS OF KOI-94d AND A RELATION FOR PLANET RADIUS, MASS, AND INCIDENT FLUX

    International Nuclear Information System (INIS)

    Weiss, Lauren M.; Marcy, Geoffrey W.; Isaacson, Howard; Kolbl, Rea; Rowe, Jason F.; Howell, Steve B.; Howard, Andrew W.; Fortney, Jonathan J.; Miller, Neil; Demory, Brice-Olivier; Seager, Sara; Fischer, Debra A.; Adams, Elisabeth R.; Dupree, Andrea K.; Johnson, John Asher; Horch, Elliott P.; Everett, Mark E.; Fabrycky, Daniel C.

    2013-01-01

    We measure the mass of a modestly irradiated giant planet, KOI-94d. We wish to determine whether this planet, which is in a 22 day orbit and receives 2700 times as much incident flux as Jupiter, is as dense as Jupiter or rarefied like inflated hot Jupiters. KOI-94 also hosts at least three smaller transiting planets, all of which were detected by the Kepler mission. With 26 radial velocities of KOI-94 from the W. M. Keck Observatory and a simultaneous fit to the Kepler light curve, we measure the mass of the giant planet and determine that it is not inflated. Support for the planetary interpretation of the other three candidates comes from gravitational interactions through transit timing variations, the statistical robustness of multi-planet systems against false positives, and several lines of evidence that no other star resides within the photometric aperture. We report the properties of KOI-94b (M P = 10.5 ± 4.6 M ⊕ , R P = 1.71 ± 0.16 R ⊕ , P = 3.74 days), KOI-94c (M P = 15.6 +5.7 -15.6 M ⊕ , R P = 4.32 ± 0.41 R ⊕ , P = 10.4 days), KOI-94d (M P = 106 ± 11 M ⊕ , R P = 11.27 ± 1.06 R ⊕ , P = 22.3 days), and KOI-94e (M P = 35 +18 -28 M ⊕ , R P = 6.56 ± 0.62 R ⊕ , P = 54.3 days). The radial velocity analyses of KOI-94b and KOI-94e offer marginal (>2σ) mass detections, whereas the observations of KOI-94c offer only an upper limit to its mass. Using the KOI-94 system and other planets with published values for both mass and radius (138 exoplanets total, including 35 with M P ⊕ ), we establish two fundamental planes for exoplanets that relate their mass, incident flux, and radius from a few Earth masses up to 13 Jupiter masses: (R P /R ⊕ ) = 1.78(M P /M ⊕ ) 0.53 (F/erg s –1 cm –2 ) –0.03 for M P ⊕ , and R P /R ⊕ = 2.45(M P /M ⊕ ) –0.039 (F/erg s –1 cm –2 ) 0.094 for M P > 150 M ⊕ . These equations can be used to predict the radius or mass of a planet.

  1. Vector mesons on the light front

    International Nuclear Information System (INIS)

    Naito, K.; Maedan, S.; Itakura, K.

    2004-01-01

    We apply the light-front quantization to the Nambu-Jona-Lasinio model with the vector interaction, and compute vector meson's mass and light-cone wavefunction in the large N limit. Following the same procedure as in the previous analyses for scalar and pseudo-scalar mesons, we derive the bound-state equations of a qq-bar system in the vector channel. We include the lowest order effects of the vector interaction. The resulting transverse and longitudinal components of the bound-state equation look different from each other. But eventually after imposing an appropriate cutoff, one finds these two are identical, giving the same mass and the same (spin-independent) light-cone wavefunction. Mass of the vector meson decreases as one increases the strength of the vector interaction

  2. Occupational heat strain in a hot underground metal mine.

    Science.gov (United States)

    Lutz, Eric A; Reed, Rustin J; Turner, Dylan; Littau, Sally R

    2014-04-01

    In a hot underground metal mine, this study evaluated the relationship between job task, physical body type, work shift, and heat strain. Thirty-one miners were evaluated during 98 shifts while performing deep shaft-sinking tasks. Continuous core body temperature, heart rate, pre- and postshift urine specific gravity (USG), and body mass index were measured. Cutting and welding tasks were associated with significantly (P < 0.05) increased core body temperature, maximum heart rate, and increased postshift urine specific gravity. Miners in the obese level II and III body mass index categories, as well as those working night shift, had lower core body temperatures (P < 0.05). This study confirms that job task, body type, and shift are risk factors for heat strain.

  3. Accretion onto hot white dwarfs in relation to symbiotic novae

    International Nuclear Information System (INIS)

    Livio, M.; Prialnik, D.; Regev, O.

    1989-01-01

    Numerical calculations are used to study the hydrodynamic evolution of a hot white dwarf with 1 solar mass accreting hydrogen-rich matter at rates between 10 to the -8th and 10 to the -6th solar masses/yr. It is found that for accretion at a rate of about 10 to the -8th solar masses/yr, nova-type outbursts of long duration occur at intervals of about 1500 yr. About half of the accreted envelope is ejected during these outbursts. At a rate of about 10 to the -7th solar masses/yr, the star alternates between comparable periods at a high plateau luminosity and giant dimensions and periods at a low luminosity and white dwarf dimension. At 10 to the -6th solar masses/yr, equilibrium is achieved with a typical red giant luminosity supported by steady hydrogen burning. It is concluded that symbiotic novae are more likely to occur in detached systems involving wind accretors. Thus, the contribution of symbiotic stars to the frequency of type I supernovae is severely constrained. 39 refs

  4. The estimated effect of mass or footprint reduction in recent light-duty vehicles on U.S. societal fatality risk per vehicle mile traveled.

    Science.gov (United States)

    Wenzel, Tom

    2013-10-01

    The National Highway Traffic Safety Administration (NHTSA) recently updated its 2003 and 2010 logistic regression analyses of the effect of a reduction in light-duty vehicle mass on US societal fatality risk per vehicle mile traveled (VMT; Kahane, 2012). Societal fatality risk includes the risk to both the occupants of the case vehicle as well as any crash partner or pedestrians. The current analysis is the most thorough investigation of this issue to date. This paper replicates the Kahane analysis and extends it by testing the sensitivity of his results to changes in the definition of risk, and the data and control variables used in the regression models. An assessment by Lawrence Berkeley National Laboratory (LBNL) indicates that the estimated effect of mass reduction on risk is smaller than in Kahane's previous studies, and is statistically non-significant for all but the lightest cars (Wenzel, 2012a). The estimated effects of a reduction in mass or footprint (i.e. wheelbase times track width) are small relative to other vehicle, driver, and crash variables used in the regression models. The recent historical correlation between mass and footprint is not so large to prohibit including both variables in the same regression model; excluding footprint from the model, i.e. allowing footprint to decrease with mass, increases the estimated detrimental effect of mass reduction on risk in cars and crossover utility vehicles (CUVs)/minivans, but has virtually no effect on light trucks. Analysis by footprint deciles indicates that risk does not consistently increase with reduced mass for vehicles of similar footprint. Finally, the estimated effects of mass and footprint reduction are sensitive to the measure of exposure used (fatalities per induced exposure crash, rather than per VMT), as well as other changes in the data or control variables used. It appears that the safety penalty from lower mass can be mitigated with careful vehicle design, and that manufacturers can

  5. Phototrophy in Mildly Acidic Hot Spring Ecosystems

    Science.gov (United States)

    Fecteau, K.; Boyd, E. S.; Shock, E.

    2014-12-01

    Microbial light-driven reduction of carbon in continental hydrothermal ecosystems is restricted to environments at temperatures less than 73 °C. In circumneutral and alkaline systems bacterial phototrophs (cyanobacteria and anoxygenic phototrophs) are suggested to be principally responsible for this activity whereas algal (i.e., eukaryotic) phototrophs are thought to be responsible for this activity in acidic systems. In Yellowstone National Park numerous examples of phototrophic microbial communities exist at high and low pH, while hot springs with intermediate pH (values 3-5) are rare and commonly dilute. It is thought that the transition from algal photosynthesis to bacterial photosynthesis occurs within this pH range. To test this hypothesis, we sequenced bacterial and eukaryal small subunit ribosomal RNA genes, analyzed pigments, and performed comprehensive geochemical measurements from 12 hot springs within this pH realm. At all sites, the largest phototrophic population was either comprised of Cyanobacteria or affiliated with the algal order Cyanidiales, which are ubiquitous in acidic springs, yet abundant sequences of both lineages were present in 8 of the 12 sites. Nevertheless, some of these samples exceeded the known temperature limit of the algae (56 °C), suggesting that these populations are dead or inactive. Indeed, one site yielded evidence for a large Cyanidiales population as the only phototrophs present, yet an experiment at the time of sampling failed to demonstrate light-driven carbon fixation, and analysis of extracted pigments showed a large amount of the chlorophyll degradation product pheophorbide a and very little intact chlorophyll, indicating photosynthesis occurred at this site when conditions were different. Our observations illustrate the dynamic nature of these systems that may be transiently conducive to photosynthesis, which may open niches for phototrophs of both domains and likely played a role in the evolution of photosynthesis.

  6. Modification of REE distribution of ordinary chondrites from Atacama (Chile) and Lut (Iran) hot deserts: Insights into the chemical weathering of meteorites

    Science.gov (United States)

    Pourkhorsandi, Hamed; D'Orazio, Massimo; Rochette, Pierre; Valenzuela, Millarca; Gattacceca, Jérôme; Mirnejad, Hassan; Sutter, Brad; Hutzler, Aurore; Aboulahris, Maria

    2017-09-01

    The behavior of rare earth elements (REEs) during hot desert weathering of meteorites is investigated. Ordinary chondrites (OCs) from Atacama (Chile) and Lut (Iran) deserts show different variations in REE composition during this process. Inductively coupled plasma-mass spectrometry (ICP-MS) data reveal that hot desert OCs tend to show elevated light REE concentrations, relative to OC falls. Chondrites from Atacama are by far the most enriched in REEs and this enrichment is not necessarily related to their degree of weathering. Positive Ce anomaly of fresh chondrites from Atacama and the successive formation of a negative Ce anomaly with the addition of trivalent REEs are similar to the process reported from Antarctic eucrites. In addition to REEs, Sr and Ba also show different concentrations when comparing OCs from different hot deserts. The stability of Atacama surfaces and the associated old terrestrial ages of meteorites from this region give the samples the necessary time to interact with the terrestrial environment and to be chemically modified. Higher REE contents and LREE-enriched composition are evidence of contamination by terrestrial soil. Despite their low degrees of weathering, special care must be taken into account while working on the REE composition of Atacama meteorites for cosmochemistry applications. In contrast, chondrites from the Lut desert show lower degrees of REE modification, despite significant weathering signed by Sr content. This is explained by the relatively rapid weathering rate of the meteorites occurring in the Lut desert, which hampers the penetration of terrestrial material by forming voluminous Fe oxide/oxyhydroxides shortly after the meteorite fall.

  7. The impact of feedback and the hot halo on the rates of gas accretion onto galaxies

    Science.gov (United States)

    Correa, Camila A.; Schaye, Joop; van de Voort, Freeke; Duffy, Alan R.; Wyithe, J. Stuart B.

    2018-04-01

    We investigate the physics that drives the gas accretion rates onto galaxies at the centers of dark matter haloes using the EAGLE suite of hydrodynamical cosmological simulations. We find that at redshifts z ≤ 2 the accretion rate onto the galaxy increases with halo mass in the halo mass range 1010 - 1011.7 M⊙, flattens between the halo masses 1011.7 - 1012.7 M⊙, and increases again for higher-mass haloes. However, the galaxy gas accretion does not flatten at intermediate halo masses when AGN feedback is switched off. To better understand these trends, we develop a physically motivated semi-analytic model of galaxy gas accretion. We show that the flattening is produced by the rate of gas cooling from the hot halo. The ratio of the cooling radius and the virial radius does not decrease continuously with increasing halo mass as generally thought. While it decreases up to ˜1013 M⊙ haloes, it increases for higher halo masses, causing an upturn in the galaxy gas accretion rate. This may indicate that in high-mass haloes AGN feedback is not sufficiently efficient. When there is no AGN feedback, the density of the hot halo is higher, the ratio of the cooling and virial radii does not decrease as much and the cooling rate is higher. Changes in the efficiency of stellar feedback can also increase or decrease the accretion rates onto galaxies. The trends can plausibly be explained by the re-accretion of gas ejected by progenitor galaxies and by the suppression of black hole growth, and hence AGN feedback, by stellar feedback.

  8. Hot springs in Hokuriku District

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K. (Hot Springs Research Center, Japan)

    1971-01-01

    In the Hokuriku district including Toyama, Ishikawa, and Fukui Prefectures, hot springs of more than 25/sup 0/C were investigated. In the Toyama Prefecture, there are 14 hot springs which are located in an area from the Kurobe River to the Tateyama volcano and in the mountainous area in the southwest. In Ishikawa Prefecture there are 16 hot springs scattered in Hakusan and its vicinity, the Kaga mountains, and in the Noto peninsula. In northern Fukui Prefecture there are seven hot springs. The hot springs in Shirakawa in Gifu Prefecture are characterized as acid springs producing exhalations and H/sub 2/S. These are attributed to the Quaternary volcanoes. The hot springs of Wakura, Katayamazu, and Awara in Ishikawa Prefecture are characterized by a high Cl content which is related to Tertiary andesite. The hot springs of Daishoji, Yamanaka, Yamashiro, Kuritsu, Tatsunokuchi, Yuwaku, and Yunotani are characterized by a low HCO/sub 3/ content. The Ca and SO/sub 4/ content decreases from east to west, and the Na and Cl content increases from west to east. These fluctuations are related to the Tertiary tuff and rhyolite. The hot springs of Kuronagi, Kinshu, and Babadani, located along the Kurobe River are characterized by low levels of dissolved components and high CO/sub 2/ and HCO/sub 3/ content. These trends are related to late Paleozoic granite. Hot springs resources are considered to be connected to geothermal resources. Ten tables, graphs, and maps are provided.

  9. Energy resource alternatives competition. Progress report for the period February 1, 1975--December 31, 1975. [Space heating and cooling, hot water, and electricity for homes, farms, and light industry

    Energy Technology Data Exchange (ETDEWEB)

    Matzke, D.J.; Osowski, D.M.; Radtke, M.L.

    1976-01-01

    This progress report describes the objectives and results of the intercollegiate Energy Resource Alternatives competition. The one-year program concluded in August 1975, with a final testing program of forty student-built alternative energy projects at the Sandia Laboratories in Albuquerque, New Mexico. The goal of the competition was to design and build prototype hardware which could provide space heating and cooling, hot water, and electricity at a level appropriate to the needs of homes, farms, and light industry. The hardware projects were powered by such nonconventional energy sources as solar energy, wind, biologically produced gas, coal, and ocean waves. The competition rules emphasized design innovation, economic feasibility, practicality, and marketability. (auth)

  10. Operation manual for the INEL on-line mass-separator facility

    International Nuclear Information System (INIS)

    Anderl, R.A.

    1984-06-01

    This report is an operation manual for an on-line mass-separator facility which is located in Building 661 at the Test Reactor Area of the Idaho National Engineering Laboratory. The facility provides mass-separated sources of short-lived fission-product radionuclides whose decay properties can be studied using a variety of nuclear spectroscopic techniques. This facility is unique in that it utilizes the gas-jet technique to transport fission products from a 252 Cf source located in a hot cell to the ion source of the mass separator. This document includes the following: (a) a detailed description of the facility, (b) identification of equipment hazards and safety controls, (c) detailed operating procedures for startup, continuous operation and shutdown, (d) operating procedures for the californium hot cell, and (e) an operator's manual for the automated moving tape collector/data acquisition system. 7 references, 16 figures, 8 tables

  11. Hot wire deposited hydrogenated amorphous silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Mahan, A.H.; Iwaniczko, E.; Nelson, B.P.; Reedy, R.C. Jr.; Crandall, R.S. [National Renewable Energy Lab., Golden, CO (United States)

    1996-05-01

    This paper details the results of a study in which low H content, high deposition rate hot wire (HW) deposited amorphous silicon (a-Si:H) has been incorporated into a substrate solar cell. The authors find that the treatment of the top surface of the HW i layer while it is being cooled from its high deposition temperature is crucial to device performance. They present data concerning these surface treatments, and correlate these treatments with Schottky device performance. The authors also present first generation HW n-i-p solar cell efficiency data, where a glow discharge (GD) {mu}c-Si(p) layer was added to complete the partial devices. No light trapping layer was used to increase the device Jsc. Their preliminary investigations have yielded efficiencies of up to 6.8% for a cell with a 4000 {Angstrom} thick HW i-layer, which degrade less than 10% after a 900 hour light soak. The authors suggest avenues for further improvement of their devices.

  12. Diversity of thermophilic archaeal isolates from hot springs in Japan

    Science.gov (United States)

    Itoh, Takashi; Yoshikawa, Naoto; Takashina, Tomonori

    2005-09-01

    In the light of the significance of extremophiles as model organisms to access possible extraterrestiral life, we provide a short review of the systematics of thermophilic Archaea, and introduce our exploratory research of novel thermophilic Archaea from hot springs in Japan. Up to date, we have isolated 162 strains of the thermophilic Archaea from hot springs in Japan by the enrichment method or the most probable number/PCR method, and the 16S rRNA gene sequences were determined to reveal their phylogenetic diversity. The sequence comparison illustrated that the isolates belonged to the orders Sulfolobales (117 isolates) , Thermoproteales (29 isolates), Desulfurococcales (8 isolates) and Thermoplasmatales (8 isolates), and there were six separate lineages representing new genera, and at least seven new species as predicted by the phylogenetic distance to known species. The collection of isolates not only included novel taxa but would give some implication for a necessity to reevaluate the current taxonomy of the thermophilic Archaea.

  13. Determination of uranium isotopic composition and 236U content of soil samples and hot particles using inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Boulyga, S F; Becker, J S

    2001-07-01

    As a result of the accident at the Chernobyl nuclear power plant (NPP) the environment was contaminated with spent nuclear fuel. The 236U isotope was used in this study to monitor the spent uranium from nuclear fallout in soil samples collected in the vicinity of the Chernobyl NPP. Nuclear track radiography was applied for the identification and extraction of hot radioactive particles from soil samples. A rapid and sensitive analytical procedure was developed for uranium isotopic ratio measurement in environmental samples based on double-focusing inductively coupled plasma mass spectrometry (DF-ICP-MS) with a MicroMist nebulizer and a direct injection high-efficiency nebulizer (DIHEN). The performance of the DF-ICP-MS with a quartz DIHEN and plasma shielded torch was studied. Overall detection efficiencies of 4 x 10(-4) and 10(-3) counts per atom were achieved for 238U in DF-ICP-QMS with the MicroMist nebulizer and DIHEN, respectively. The rate of formation of uranium hydride ions UH+/U+ was 1.2 x 10(-4) and 1.4 x 10(-4), respectively. The precision of short-term measurements of uranium isotopic ratios (n = 5) in 1 microg L(-1) NBS U-020 standard solution was 0.11% (238U/235U) and 1.4% (236U/238U) using a MicroMist nebulizer and 0.25% (235U/238U) and 1.9% (236U/P38U) using a DIHEN. The isotopic composition of all investigated Chernobyl soil samples differed from those of natural uranium; i.e. in these samples the 236U/238U ratio ranged from 10(-5) to 10(-3). Results obtained with ICP-MS, alpha- and gamma-spectrometry showed differences in the migration properties of spent uranium, plutonium, and americium. The isotopic ratio of uranium was also measured in hot particles extracted from soil samples.

  14. Determination of uranium isotopic composition and 236U content of soil samples and hot particles using inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Boulyga, S.F.; Becker, J.S.

    2001-01-01

    As a result of the accident at the Chernobyl nuclear power plant (NPP) the environment was contaminated with spent nuclear fuel. The 236 U isotope was used in this study to monitor the spent uranium from nuclear fallout in soil samples collected in the vicinity of the Chernobyl NPP. Nuclear track radiography was applied for the identification and extraction of hot radioactive particles from soil samples. A rapid and sensitive analytical procedure was developed for uranium isotopic ratio measurement in environmental samples based on double-focusing inductively coupled plasma mass spectrometry (DF-ICP-MS) with a MicroMist nebulizer and a direct injection high-efficiency nebulizer (DIHEN). The performance of the DF-ICP-MS with a quartz DIHEN and plasma shielded torch was studied. Overall detection efficiencies of 4 x 10 -4 and 10 -3 counts per atom were achieved for 238 U in DF-ICP-QMS with the MicroMist nebulizer and DIHEN, respectively. The rate of formation of uranium hydride ions UH + /U + was 1.2 x 10 -4 and 1.4 x 10 -4 , respectively. The precision of short-term measurements of uranium isotopic ratios (n = 5) in 1 μg L -1 NBS U-020 standard solution was 0.11% ( 238 U/ 235 U) and 1.4% ( 236 U/ 238 U) using a MicroMist nebulizer and 0.25% ( 235 U/ 238 U) and 1.9% ( 236 U/ 238 U) using a DIHEN. The isotopic composition of all investigated Chernobyl soil samples differed from those of natural uranium; i.e. in these samples the 236 U/ 238 U ratio ranged from 10 -5 to 10 -3 . Results obtained with ICP-MS, α- and γ-spectrometry showed differences in the migration properties of spent uranium, plutonium, and americium. The isotopic ratio of uranium was also measured in hot particles extracted from soil samples. (orig.)

  15. ESA uncovers Geminga's `hot spot'

    Science.gov (United States)

    2004-07-01

    16 July 2004 Astronomers using ESA’s X-ray observatory XMM-Newton have detected a small, bright ‘hot spot’ on the surface of the neutron star called Geminga, 500 light-years away. The hot spot is the size of a football field and is caused by the same mechanism producing Geminga’s X-ray tails. This discovery identifies the missing link between the X-ray and gamma-ray emission from Geminga. hi-res Size hi-res: 1284 kb Credits: ESA, P. Caraveo (IASF, Milan) Geminga's hot spot This figure shows the effects of charged particles accelerated in the magnetosphere of Geminga. Panel (a) shows an image taken with the EPIC instrument on board the XMM-Newton observatory. The bright tails, made of particles kicked out by Geminga’s strong magnetic field, trail the neutron star as it moves about in space. Panel (b) shows how electrically charged particles interact with Geminga’s magnetic field. For example, if electrons (blue) are kicked out by the star, positrons (in red) hit the star’s magnetic poles like in an ‘own goal’. Panel (c) illustrates the size of Geminga’s magnetic field (blue) compared to that of the star itself at the centre (purple). The magnetic field is tilted with respect to Geminga’s rotation axis (red). Panel (d) shows the magnetic poles of Geminga, where charged particles hit the surface of the star, creating a two-million degrees hot spot, a region much hotter than the surroundings. As the star spins on its rotation axis, the hot spot comes into view and then disappears, causing the periodic colour change seen by XMM-Newton. An animated version of the entire sequence can be found at: Click here for animated GIF [low resolution, animated GIF, 5536 KB] Click here for AVI [high resolution, AVI with DIVX compression, 19128 KB] hi-res Size hi-res: 371 kb Credits: ESA, P. Caraveo (IASF, Milan) Geminga's hot spot, panel (a) Panel (a) shows an image taken with the EPIC instrument on board the XMM-Newton observatory. The bright tails, made of

  16. Pulsar formation and the fall back mass fraction

    International Nuclear Information System (INIS)

    Colgate, S.A.

    1988-01-01

    The picture of the explosion of 1987A following collapse to a neutron star and neutrino emission is difficult to reconcile with the subsequent behavior of the ejected mass. It is shown that the inner solar mass of ejected matter should progressively fall back onto the neutron star after it collides with the outer 10--15 M circle and after an initial phase of explosion driven by a hot bubble for t approx-gt 2 x 10 3 s. This fall back is augmented due to heating by the radioactive decay of 56 Ni. The matter accreted onto the neutron star rapidly cools due to neutrino emission and merges with the neutron star, thus resulting in zero back pressure to the free falling matter. The predicted fall back mass approx-gt 1 M circle is far larger than is consistent with observations. The author discusses how the most likely explanation is that the hot radiation dominated bubble is continuously heated by neutrino emission from continuing accretion. This accretion continues until the presumed pulsar magnetic field exceeds the bubble pressure

  17. Simultaneous measurement of the concentrations of soot particles and gas species in light hydrocarbon flames using mass spectrometry

    International Nuclear Information System (INIS)

    Li, Qingxun; Liu, Fang; Wang, Dezheng; Wang, Tiefeng

    2014-01-01

    Besides gas species concentrations, soot volume fractions are also important data in the study of flames. This work describes the simultaneous measurement of the concentrations of soot and gas species in light hydrocarbon flames by in situ sampling and mass spectrometry (MS).The reaction medium was frozen by sampling into a very low-pressure tube, and the soot selectivity (proportion of carbon atoms in the reactant converted to soot) was determined from the C and H mass balances using the measured concentrations of the gas species and the mass of soot present per unit gas volume. The H/C ratio of the soot was measured by a thermogravimetry–mass spectrometry combination. The soot volume fraction was calculated from the soot selectivity and density of the soot. The soot selectivity measured by this reduced pressure sampling mass spectrometry (RPSMS) method was verified by measurements using the gravimetric sampling technique where the mass of soot collected in a volume of gas was weighed by a high precision balance. For most of the measurements, the uncertainty in the soot volume fraction was ±5%, but this would be larger when the soot volume fractions are less than 1 ppm. For demonstration, the RPSMS method was used to study a methane fuel-rich flame where the soot volume fractions were 1–5 ppm. The simultaneous measurement of concentrations of soot and gas species is useful for the quantitative study of flames. (paper)

  18. Effect of Various External Shading Devices on Windows for Minimum Heat Gain and Adequate Day lighting into Buildings of Hot and Dry Climatic Zone in India

    Directory of Open Access Journals (Sweden)

    Kirankumar Gorantla

    2018-01-01

    Full Text Available Glass is the major component of the building envelope to provide visual comfort to inside the buildings. In général clear and bronze glass was used as a main building envelope for both residential and commercial buildings to provide better day lighting into the buildings. If we use more glass area as a building envelope more radiation allows into the buildings. So that it is necessary to reduce more solar radiation and provide sufficient daylight factor inside the building's through glass windows with the help of external devices called shading devices. In this work four shading devices was tried on bronze glass window to find the heat gain and daylighting into buildings. This paper presents the experimental measurement of spectral characteristics of bronze glass which include transmission and reflection in entire solar spectrum region (300nm-2500nm based on ASTM standards. A MATLAB code was developed to compute visible and solar optical properties as per the British standards. A building model was designed by design builder software tool. 40% window to wall ratio was considered for building models, thermal and day lighting analysis of buildings through windows was carried out in Energy plus software tool for hot and dry climatic zone of India.

  19. Hot Gas Halos in Galaxies

    Science.gov (United States)

    Mulchaey, John

    Most galaxy formation models predict that massive low-redshift disk galaxies are embedded in extended hot halos of externally accreted gas. Such gas appears necessary to maintain ongoing star formation in isolated spirals like the Milky Way. To explain the large population of red galaxies in rich groups and clusters, most galaxy evolution models assume that these hot gas halos are stripped completely when a galaxy enters a denser environment. This simple model has been remarkably successful at reproducing many observed properties of galaxies. Although theoretical arguments suggest hot gas halos are an important component in galaxies, we know very little about this gas from an observational standpoint. In fact, previous observations have failed to detect soft X-ray emission from such halos in disk galaxies. Furthermore, the assumption that hot gas halos are stripped completely when a galaxy enters a group or cluster has not been verified. We propose to combine proprietary and archival XMM-Newton observations of galaxies in the field, groups and clusters to study how hot gas halos are impacted by environment. Our proposed program has three components: 1) The deepest search to date for a hot gas halo in a quiescent spiral galaxy. A detection will confirm a basic tenet of disk galaxy formation models, whereas a non-detection will seriously challenge these models and impose new constraints on the growth mode and feedback history of disk galaxies. 2) A detailed study of the hot gas halos properties of field early-type galaxies. As environmental processes such as stripping are not expected to be important in the field, a study of hot gas halos in this environment will allow us to better understand how feedback and other internal processes impact hot gas halos. 3) A study of hot gas halos in the outskirts of groups and clusters. By comparing observations with our suite of simulations we can begin to understand what role the stripping of hot gas halos plays in galaxy

  20. Setting Mechanical Properties of High Strength Steels for Rapid Hot Forming Processes

    Science.gov (United States)

    Löbbe, Christian; Hering, Oliver; Hiegemann, Lars; Tekkaya, A. Erman

    2016-01-01

    Hot stamping of sheet metal is an established method for the manufacturing of light weight products with tailored properties. However, the generally-applied continuous roller furnace manifests two crucial disadvantages: the overall process time is long and a local setting of mechanical properties is only feasible through special cooling techniques. Hot forming with rapid heating directly before shaping is a new approach, which not only reduces the thermal intervention in the zones of critical formability and requested properties, but also allows the processing of an advantageous microstructure characterized by less grain growth, additional fractions (e.g., retained austenite), and undissolved carbides. Since the austenitization and homogenization process is strongly dependent on the microstructure constitution, the general applicability for the process relevant parameters is unknown. Thus, different austenitization parameters are analyzed for the conventional high strength steels 22MnB5, Docol 1400M, and DP1000 in respect of the mechanical properties. In order to characterize the resulting microstructure, the light optical and scanning electron microscopy, micro and macro hardness measurements, and the X-ray diffraction are conducted subsequent to tensile tests. The investigation proves not only the feasibility to adjust the strength and ductility flexibly, unique microstructures are also observed and the governing mechanisms are clarified. PMID:28773354

  1. Possibility of faster-than-light particles with real mass

    International Nuclear Information System (INIS)

    Schommers, W.

    1982-01-01

    The author derives a new expression for the dependence of mass on velocity without using any space-time conception. This expression is more general than the corresponding law of the special theory of relativity (STR). The deviations from the STR increase with increasing rest mass. Thus one should measure the dependence of mass on velocity for particles (or systems) with a large rest mass. The theory predicts that particles with real mass can travel with hyperlight velocities. The space-time picture discussed here is very close to Mach's conception: it is assumed that the cause for the dynamical behaviour of a particle, which is in uniform translational motion, is due to the action of all the other masses in the universe. Space-time is eliminated as an active cause and, in contrast with the STR, space-time does not form an absolute continuum within the theory discussed here. It turns out that effects based on the transformation formulas (existing between the coordinates and time in a stationary frame and the coordinates and time in a moving frame) are identical to those expected from the Lorentz transformations. (Auth.)

  2. Hot flashes and sleep in women.

    Science.gov (United States)

    Moe, Karen E

    2004-12-01

    Sleep disturbances during menopause are often attributed to nocturnal hot flashes and 'sweats' associated with changing hormone patterns. This paper is a comprehensive critical review of the research on the relationship between sleep disturbance and hot flashes in women. Numerous studies have found a relationship between self-reported hot flashes and sleep complaints. However, hot flash studies using objective sleep assessment techniques such as polysomnography, actigraphy, or quantitative analysis of the sleep EEG are surprisingly scarce and have yielded somewhat mixed results. Much of this limited evidence suggests that hot flashes are associated with objectively identified sleep disruption in at least some women. At least some of the negative data may be due to methodological issues such as reliance upon problematic self-reports of nocturnal hot flashes and a lack of concurrent measures of hot flashes and sleep. The recent development of a reliable and non-intrusive method for objectively identifying hot flashes during the night should help address the need for substantial additional research in this area. Several areas of clinical relevance are described, including the effects of discontinuing combined hormone therapy (estrogen plus progesterone) or estrogen-only therapy, the possibility of hot flashes continuing for many years after menopause, and the link between hot flashes and depression.

  3. Evolution of hot galactic flows

    International Nuclear Information System (INIS)

    Loewenstein, M.; Mathews, W.G.

    1987-01-01

    The time-dependent equations describing galactic flows, including detailed models for the evolving source terms, are integrated over a Hubble time for two elliptical galaxies with total masses of 3.1 x 10 to the 12th and 8.3 x 10 to the 12th solar masses, 90 percent of which resides in extended, nonluminous halos. The standard supernova rate of Tammann and a rate 4 times smaller are considered for each galaxy model. The combination of the extended gravitational potential of the dark halo and the time-dependent source terms generally lead to the development of massive, quasi-hydrostatic, nearly isothermal distributions of gas at about 10 to the 7th K with cooling inflows inside their galactic cores. For the less massive galaxy with the higher supernova rate, however, a low-luminosity supersonic galactic wind develops. The effects of a lowered metal abundance, thermal conduction, and the absence of a massive halo are explored separately for one of the present models. The X-ray luminosities of the hot gas in the models with dark halos and the lower supernova rate are in good agreement with Einstein observations of early-type galaxies. 42 references

  4. Accurate light-time correction due to a gravitating mass

    Energy Technology Data Exchange (ETDEWEB)

    Ashby, Neil [Department of Physics, University of Colorado, Boulder, CO (United States); Bertotti, Bruno, E-mail: ashby@boulder.nist.go [Dipartimento di Fisica Nucleare e Teorica, Universita di Pavia (Italy)

    2010-07-21

    This technical paper of mathematical physics arose as an aftermath of the 2002 Cassini experiment (Bertotti et al 2003 Nature 425 374-6), in which the PPN parameter {gamma} was measured with an accuracy {sigma}{sub {gamma}} = 2.3 x 10{sup -5} and found consistent with the prediction {gamma} = 1 of general relativity. The Orbit Determination Program (ODP) of NASA's Jet Propulsion Laboratory, which was used in the data analysis, is based on an expression (8) for the gravitational delay {Delta}t that differs from the standard formula (2); this difference is of second order in powers of m-the gravitational radius of the Sun-but in Cassini's case it was much larger than the expected order of magnitude m{sup 2}/b, where b is the distance of the closest approach of the ray. Since the ODP does not take into account any other second-order terms, it is necessary, also in view of future more accurate experiments, to revisit the whole problem, to systematically evaluate higher order corrections and to determine which terms, and why, are larger than the expected value. We note that light propagation in a static spacetime is equivalent to a problem in ordinary geometrical optics; Fermat's action functional at its minimum is just the light-time between the two end points A and B. A new and powerful formulation is thus obtained. This method is closely connected with the much more general approach of Le Poncin-Lafitte et al (2004 Class. Quantum Grav. 21 4463-83), which is based on Synge's world function. Asymptotic power series are necessary to provide a safe and automatic way of selecting which terms to keep at each order. Higher order approximations to the required quantities, in particular the delay and the deflection, are easily obtained. We also show that in a close superior conjunction, when b is much smaller than the distances of A and B from the Sun, say of order R, the second-order correction has an enhanced part of order m{sup 2}R/b{sup 2}, which

  5. MIGRATION THEN ASSEMBLY: FORMATION OF NEPTUNE-MASS PLANETS INSIDE 1 AU

    International Nuclear Information System (INIS)

    Hansen, Brad M. S.; Murray, Norm

    2012-01-01

    We demonstrate that the observed distribution of 'hot Neptune'/'super-Earth' systems is well reproduced by a model in which planet assembly occurs in situ, with no significant migration post-assembly. This is achieved only if the amount of mass in rocky material is ∼50-100 M ⊕ interior to 1 AU. Such a reservoir of material implies that significant radial migration of solid material takes place, and that it occurs before the stage of final planet assembly. The model not only reproduces the general distribution of mass versus period but also the detailed statistics of multiple planet systems in the sample. We furthermore demonstrate that cores of this size are also likely to meet the criterion to gravitationally capture gas from the nebula, although accretion is rapidly limited by the opening of gaps in the gas disk. If the mass growth is limited by this tidal truncation, then the scenario sketched here naturally produces Neptune-mass objects with substantial components of both rock and gas, as is observed. The quantitative expectations of this scenario are that most planets in the 'hot Neptune/super-Earth' class inhabit multiple-planet systems, with characteristic orbital spacings. The model also provides a natural division into gas-rich (hot Neptune) and gas-poor (super-Earth) classes at fixed period. The dividing mass ranges from ∼3 M ⊕ at 10 day orbital periods to ∼10 M ⊕ at 100 day orbital periods. For orbital periods <10 days, the division is less clear because a gas atmosphere may be significantly eroded by stellar radiation.

  6. Printable candlelight-style organic light-emitting diode

    Science.gov (United States)

    Jou, J. H.; Singh, M.; Song, W. C.; Liu, S. H.

    2017-06-01

    Candles or oil lamps are currently the most friendly lighting source to human eyes, physiology, ecosystems, artifacts, environment, and night skies due to their blue light-less emission. Candle light also exhibits high light-quality that provides visual comfort. However, they are relatively low in power efficacy (0.3 lm/W), making them energy-wasting, besides having problems like scorching hot, burning, catching fire, flickering, carbon blacking, oxygen consuming, and release of green house gas etc. In contrast, candlelight organic light-emitting diode (OLED) can be made blue-hazard free and energy-efficient. The remaining challenges are to maximize its light-quality and enable printing feasibility, the latter of which would pave a way to cost-effective manufacturing. We hence demonstrate herein the design and fabrication of a candlelight OLED via wet-process. From retina protection perspective, its emission is 13, 12 and 8 times better than those of the blue-enriched white CFL, LED and OLED. If used at night, it is 9, 6 and 4 times better from melatonin generation perspective.

  7. Stellar by Day, Planetary by Night: Atmospheres of Ultra-Hot Jupiters

    Science.gov (United States)

    Hensley, Kerry

    2018-06-01

    Move over, hot Jupiters theres an even stranger kind of giant planet in the universe! Ultra-hot Jupiters are so strongly irradiated that the molecules in their atmospheres split apart. What does this mean for heat transport on these planets?Atmospheres of Exotic PlanetsA diagram showing the orbit of an ultra-hot Jupiter and the longitudes at which dissociation and recombination occur. [Bell Cowan 2018]Similar to hot Jupiters, ultra-hot Jupiters are gas giants with atmospheres dominated by molecular hydrogen. What makes them interesting is that their dayside atmospheres are so hot that the molecules dissociate into individual hydrogen atoms more like the atmospheres of stars than planets.Because of the intense stellar irradiation, there is also an extreme temperature difference between the day and night sides of these planets potentially more than 1,000 K! As the stellar irradiation increases, the dayside atmosphere becomes hotter and hotter and the temperature difference between the day and night sides increases.When hot atomic hydrogen is transported into cooler regions (by winds, for instance), it recombines to form H2 molecules and heats the gas, effectively transporting heat from one location to another. This is similar to how the condensation of water redistributes heat in Earths atmosphere but what effect does this phenomenon have on the atmospheres of ultra-hot Jupiters?Maps of atmospheric temperature of molecular hydrogen dissociation fraction for three wind speeds. Click to enlarge. [Bell Cowan 2018]Modeling Heat RedistributionTaylor Bell and Nicolas Cowan (McGill University) used an energy-balance model to estimate the effects of H2 dissociation and recombination on heat transport in ultra-hot Jupiter atmospheres. In particular, they explored the redistribution of heat and how it affects the resultant phase curve the curve that describes the combination of reflected and thermally emitted light from the planet, observed as a function of its phase angle

  8. THE ROMER DELAY AND MASS RATIO OF THE sdB+dM BINARY 2M 1938+4603 FROM KEPLER ECLIPSE TIMINGS

    Energy Technology Data Exchange (ETDEWEB)

    Barlow, Brad N.; Wade, Richard A.; Liss, Sandra E. [Department of Astronomy and Astrophysics, 525 Davey Lab, Pennsylvania State University, University Park, PA 16802 (United States)

    2012-07-10

    The eclipsing binary system 2M 1938+4603 consists of a pulsating hot subdwarf B star and a cool M dwarf companion in an effectively circular three-hour orbit. The light curve shows both primary and secondary eclipses, along with a strong reflection effect from the cool companion. Here, we present constraints on the component masses and eccentricity derived from the Romer delay of the secondary eclipse. Using six months of publicly available Kepler photometry obtained in short-cadence mode, we fit model profiles to the primary and secondary eclipses to measure their centroid values. We find that the secondary eclipse arrives on average 2.06 {+-} 0.12 s after the midpoint between primary eclipses. Under the assumption of a circular orbit, we calculate from this time delay a mass ratio of q = 0.2691 {+-} 0.0018 and individual masses of M{sub sd} = 0.372 {+-} 0.024 M{sub Sun} and M{sub c} = 0.1002 {+-} 0.0065 M{sub Sun} for the sdB and M dwarf, respectively. These results differ slightly from those of a previously published light-curve modeling solution; this difference, however, may be reconciled with a very small eccentricity, ecos {omega} Almost-Equal-To 0.00004. We also report a decrease in the orbital period of P-dot = (-1.23 {+-} 0.07) Multiplication-Sign 10{sup -10}.

  9. Phase structure of hot and/or dense QCD with the Schwinger-Dyson equation

    Energy Technology Data Exchange (ETDEWEB)

    Takagi, Satoshi [Nagoya Univ., Nagoya, Aichi (Japan)

    2002-09-01

    We investigate the phase structure of the hot and/or dense QCD using the Schwinger-Dyson equation (SDE) with the improved ladder approximation in the Landau gauge. We solve the coupled SDE for the Majorana masses of the quark and antiquark (separately from the SDE for the Dirac mass) in the finite temperature and/or chemical potential region. The resultant phase structure is rather different from those by other analyses. In addition to this analysis we investigate the phase structure with the different two types of the SDE, in one of which the Majorana mass gap of the antiquark is neglected, while in the other of which the Majorana mass gap of the quark and that of the antiquark are set to be equal. The effect of the Debye mass of the gluon on the phase structure is also investigated. (author)

  10. Understanding the physics of changing mass phenomena

    NARCIS (Netherlands)

    Ellermeijer, A.L.

    2008-01-01

    Changing mass phenomena, like a falling chain or a bungee jumper, might give surprising results, even for experienced physicists. They have resulted in hot discussions in journals, in which for instance Physics professors claim the impossibility of an acceleration larger then g in case of a bungee

  11. Update on the KELT Transit Survey: Hot Planets around Hot Stars

    Science.gov (United States)

    Gaudi, B. Scott; Stassun, Keivan G.; Pepper, Joshua; KELT Collaboration

    2018-01-01

    The KELT Transit Survey consists of a pair of small-aperture, wide-angle automated telescopes located at Winer Observatory in Sonoita, Arizona and the South African Astronomical Observatory (SAAO) in Sutherland, South Africa. Together, they are surveying roughly 70% of the sky for transiting planets. By virtue of their small apertures (42 mm) and large fields-of-view (26 degrees x 26 degrees), KELT is most sensitive to hot Jupiters transiting relatively bright (V~8-11), and thus relatively hot stars. I will provide an update on the planets discovered by KELT, focusing in detail on our recent discoveries of very hot planets transiting several bright A and early F stars.

  12. Hot subluminous star: HDE 283048

    International Nuclear Information System (INIS)

    Laget, M.; Vuillemin, A.; Parsons, S.B.; Henize, K.G.; Wray, J.D.

    1978-01-01

    The star HDE 283048, located at α = 3/sup h/50/sup m/.3, delta = +25 0 36', shows a strong ultraviolet continuum. Ground-based observations indicate a hot-dominated composite spectrum. Several lines of evidence suggest that the hot component is a hot subdwarf. 2 figures

  13. SMA millimeter observations of hot molecular cores

    Energy Technology Data Exchange (ETDEWEB)

    Hernández-Hernández, Vicente; Zapata, Luis; Kurtz, Stan [Centro de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, Apdo. Postal 3-72 (Xangari), 58090 Morelia, Michoacán (Mexico); Garay, Guido, E-mail: v.hernandez@crya.unam.mx [Departamento de Astronomía, Universidad de Chile, Camino del Observatorio 1515, Las Condes, Santiago (Chile)

    2014-05-01

    We present Submillimeter Array observations in the 1.3 mm continuum and the CH{sub 3}CN (12 {sub K}-11 {sub K}) line of 17 hot molecular cores associated with young high-mass stars. The angular resolution of the observations ranges from 1.''0 to 4.''0. The continuum observations reveal large (>3500 AU) dusty structures with gas masses from 7 to 375 M {sub ☉}, which probably surround multiple young stars. The CH{sub 3}CN line emission is detected toward all the molecular cores at least up to the K = 6 component and is mostly associated with the emission peaks of the dusty objects. We used the multiple K-components of the CH{sub 3}CN and both the rotational diagram method and a simultaneous synthetic local thermodynamic equilibrium model with the XCLASS program to estimate the temperatures and column densities of the cores. For all sources, we obtained reasonable fits from XCLASS by using a model that combines two components: an extended and warm envelope and a compact hot core of molecular gas, suggesting internal heating by recently formed massive stars. The rotational temperatures lie in the range of 40-132 K and 122-485 K for the extended and compact components, respectively. From the continuum and CH{sub 3}CN results, we infer fractional abundances from 10{sup –9} to 10{sup –7} toward the compact inner components, which increase with the rotational temperature. Our results agree with a chemical scenario in which the CH{sub 3}CN molecule is efficiently formed in the gas phase above 100-300 K, and its abundance increases with temperature.

  14. HOT AND COLD GALACTIC GAS IN THE NGC 2563 GALAXY GROUP

    International Nuclear Information System (INIS)

    Rasmussen, Jesper; Bai, Xue-Ning; Mulchaey, John S.; Van Gorkom, J. H.; Lee, Duane; Jeltema, Tesla E.; Zabludoff, Ann I.; Wilcots, Eric; Martini, Paul; Roberts, Timothy P.

    2012-01-01

    The role of environmentally induced gas stripping in driving galaxy evolution in groups remains poorly understood. Here we present extensive Chandra and Very Large Array mosaic observations of the hot and cold interstellar medium within the members of the nearby, X-ray bright NGC 2563 group, a prime target for studies of the role of gas stripping and interactions in relatively small host halos. Our observations cover nearly all group members within a projected radius of 1.15 Mpc (∼1.4 R vir ) of the group center, down to a limiting X-ray luminosity and H I mass of 3 × 10 39 erg s –1 and 2 × 10 8 M ☉ , respectively. The X-ray data are consistent with efficient ram pressure stripping of the hot gas halos of early-type galaxies near the group core, but no X-ray tails are seen and the limited statistics preclude strong conclusions. The H I results suggest moderate H I mass loss from the group members when compared to similar field galaxies. Six of the 20 H I-detected group members show H I evidence of ongoing interactions with other galaxies or with the intragroup medium. Suggestive evidence is further seen for galaxies with close neighbors in position-velocity space to show relatively low H I content, consistent with tidal removal of H I. The results thus indicate removal of both hot and cold gas from the group members via a combination of ram pressure stripping and tidal interactions. We also find that 16 of the 20 H I detections occur on one side of the group, reflecting an unusual morphological segregation whose origin remains unclear.

  15. Extracting the temperature of hot carriers in time- and angle-resolved photoemission

    International Nuclear Information System (INIS)

    Ulstrup, Søren; Hofmann, Philip; Johannsen, Jens Christian; Grioni, Marco

    2014-01-01

    The interaction of light with a material's electronic system creates an out-of-equilibrium (non-thermal) distribution of optically excited electrons. Non-equilibrium dynamics relaxes this distribution on an ultrafast timescale to a hot Fermi-Dirac distribution with a well-defined temperature. The advent of time- and angle-resolved photoemission spectroscopy (TR-ARPES) experiments has made it possible to track the decay of the temperature of the excited hot electrons in selected states in the Brillouin zone, and to reveal their cooling in unprecedented detail in a variety of emerging materials. It is, however, not a straightforward task to determine the temperature with high accuracy. This is mainly attributable to an a priori unknown position of the Fermi level and the fact that the shape of the Fermi edge can be severely perturbed when the state in question is crossing the Fermi energy. Here, we introduce a method that circumvents these difficulties and accurately extracts both the temperature and the position of the Fermi level for a hot carrier distribution by tracking the occupation statistics of the carriers measured in a TR-ARPES experiment

  16. Extracting the temperature of hot carriers in time- and angle-resolved photoemission.

    Science.gov (United States)

    Ulstrup, Søren; Johannsen, Jens Christian; Grioni, Marco; Hofmann, Philip

    2014-01-01

    The interaction of light with a material's electronic system creates an out-of-equilibrium (non-thermal) distribution of optically excited electrons. Non-equilibrium dynamics relaxes this distribution on an ultrafast timescale to a hot Fermi-Dirac distribution with a well-defined temperature. The advent of time- and angle-resolved photoemission spectroscopy (TR-ARPES) experiments has made it possible to track the decay of the temperature of the excited hot electrons in selected states in the Brillouin zone, and to reveal their cooling in unprecedented detail in a variety of emerging materials. It is, however, not a straightforward task to determine the temperature with high accuracy. This is mainly attributable to an a priori unknown position of the Fermi level and the fact that the shape of the Fermi edge can be severely perturbed when the state in question is crossing the Fermi energy. Here, we introduce a method that circumvents these difficulties and accurately extracts both the temperature and the position of the Fermi level for a hot carrier distribution by tracking the occupation statistics of the carriers measured in a TR-ARPES experiment.

  17. Statistical hot spot analysis of reactor cores

    International Nuclear Information System (INIS)

    Schaefer, H.

    1974-05-01

    This report is an introduction into statistical hot spot analysis. After the definition of the term 'hot spot' a statistical analysis is outlined. The mathematical method is presented, especially the formula concerning the probability of no hot spots in a reactor core is evaluated. A discussion with the boundary conditions of a statistical hot spot analysis is given (technological limits, nominal situation, uncertainties). The application of the hot spot analysis to the linear power of pellets and the temperature rise in cooling channels is demonstrated with respect to the test zone of KNK II. Basic values, such as probability of no hot spots, hot spot potential, expected hot spot diagram and cumulative distribution function of hot spots, are discussed. It is shown, that the risk of hot channels can be dispersed equally over all subassemblies by an adequate choice of the nominal temperature distribution in the core

  18. Hot model of formation of galaxies: galaxy sizes and the origin of the stellar component

    International Nuclear Information System (INIS)

    Suchkov, A.A.

    1988-01-01

    Within the framework of the ''hot'' model of the formation of galaxies, a mechanism proposed is by which a protogalaxy transforms into a stellar system. It gives a quantitative relation between the mass and size of galaxy which well fits in with the observational relation; also it specifies two characteristic values of mass which coincide with masses of stars and globular clusters. It is shown that a ''hot protogalaxy'' (T ∼ 10 7 K) contracting under the gravity of a massive dark halo attains a critical size and fragments into separate clouds via thermal instability. The clouds form a collisionless system which collapses quasiadiabatically and reaches the equilibrium after its size decreases approximately by a factor of two. This defines the final zero of the system:R S ∼ 10 (M S /10 11 M sun ) 1/2 kpc. It is close to the sizes of elliptical galaxies and halos of spiral galaxies, and agree with the Faber-Jackson relation. The instability forms clouds with temperatures T c ' ∼ 10 4 K and T c ∼ (10-10 2 ) K. The sharp temperature and density change caused by the cloud formation leads to a sharp change of the Jeans mass. It value drops to M J ∼ 10 5 M sun for the clouds with T c ∼ 10 4 K, and to M J ' ∼ (10 -1 -10) M sun for the clouds with T c ' ∼ (10-10 2 ) K. This may explain why the mass spectrum of galactic objects is rather sharply peaked at two values corresponding to stellar mass and globular cluster mass

  19. Supersymmetric Properties of Hadron Physics from Light-Front Holography and Superconformal Algebra and other Advances in Light-Front QCD

    Science.gov (United States)

    Brodsky, Stanley J.

    2018-05-01

    Light-front holography, together with superconformal algebra, have provided new insights into the physics of color confinement and the spectroscopy and dynamics of hadrons. As shown by de Alfaro, Fubini and Furlan, a mass scale can appear in the equations of motion without affecting the conformal invariance of the action if one adds a term to the Hamiltonian proportional to the dilatation operator or the special conformal operator. If one applies the procedure of de Alfaro et al. to the frame-independent light-front Hamiltonian, it leads uniquely to a confining q \\bar{q} potential κ ^4 ζ ^2, where ζ ^2 is the light-front radial variable related in momentum space to the q \\bar{q} invariant mass. The same result, including spin terms, is obtained using light-front holography—the duality between the front form and AdS_5, the space of isometries of the conformal group—if one modifies the action of AdS_5 by the dilaton e^{κ ^2 z^2} in the fifth dimension z. When one generalizes this procedure using superconformal algebra, the resulting light-front eigensolutions lead to a a unified Regge spectroscopy of meson, baryon, and tetraquarks, including supersymmetric relations between their masses and their wavefunctions. One also predicts hadronic light-front wavefunctions and observables such as structure functions, transverse momentum distributions, and the distribution amplitudes. The mass scale κ underlying confinement and hadron masses can be connected to the parameter Λ_{\\overline{MS}} in the QCD running coupling by matching the nonperturbative dynamics to the perturbative QCD regime. The result is an effective coupling α _s(Q^2) defined at all momenta. The matching of the high and low momentum transfer regimes determines a scale Q_0 which sets the interface between perturbative and nonperturbative hadron dynamics. I also discuss a number of applications of light-front phenomenology.

  20. Prediction of hot spots in protein interfaces using a random forest model with hybrid features.

    Science.gov (United States)

    Wang, Lin; Liu, Zhi-Ping; Zhang, Xiang-Sun; Chen, Luonan

    2012-03-01

    Prediction of hot spots in protein interfaces provides crucial information for the research on protein-protein interaction and drug design. Existing machine learning methods generally judge whether a given residue is likely to be a hot spot by extracting features only from the target residue. However, hot spots usually form a small cluster of residues which are tightly packed together at the center of protein interface. With this in mind, we present a novel method to extract hybrid features which incorporate a wide range of information of the target residue and its spatially neighboring residues, i.e. the nearest contact residue in the other face (mirror-contact residue) and the nearest contact residue in the same face (intra-contact residue). We provide a novel random forest (RF) model to effectively integrate these hybrid features for predicting hot spots in protein interfaces. Our method can achieve accuracy (ACC) of 82.4% and Matthew's correlation coefficient (MCC) of 0.482 in Alanine Scanning Energetics Database, and ACC of 77.6% and MCC of 0.429 in Binding Interface Database. In a comparison study, performance of our RF model exceeds other existing methods, such as Robetta, FOLDEF, KFC, KFC2, MINERVA and HotPoint. Of our hybrid features, three physicochemical features of target residues (mass, polarizability and isoelectric point), the relative side-chain accessible surface area and the average depth index of mirror-contact residues are found to be the main discriminative features in hot spots prediction. We also confirm that hot spots tend to form large contact surface areas between two interacting proteins. Source data and code are available at: http://www.aporc.org/doc/wiki/HotSpot.

  1. Study of boundary effect of brightness variations of spherical star with two hot precessing spots

    International Nuclear Information System (INIS)

    Kyurkchieva, D.P.; Shkodrov, V.G.

    1984-01-01

    In order to determine the low governing the total brightness variation of a spherical star for the period α<=Ωt<=π-α', the spots behaviour in the intervals 0<=Ωt<=α', π-α'<=Ωt<=π has to be investigated. The article contains an analysis of the boundary effects at which the hot spots are projected as parts of an ellipse on the star's visible disc. The area of the projections of the hot spots on the tangential plane toward the celestial sphere in the above intervals is determined. The equation obtained is sufficient for the determination of the relative light variation of the star. The equation is applied to the parameters of SS433

  2. ''Heavy light bullets'' in electron-positron plasma

    International Nuclear Information System (INIS)

    Berezhiani, V.I.; Mahajan, S.M.

    1995-03-01

    The nonlinear propagation of circularly polarized electromagnetic waves with relativistically strong amplitudes in an unmagnetized hot electron-positron plasma with a small fraction of ions is investigated. The possibility of finding localized solutions in such a plasma is explored. It is shown that these plasmas support the propagation of ''heavy light bullets''; nondiffracting and nondispersive electromagnetic (EM) pulses with large density bunching. (author). 24 refs, 12 figs

  3. MIS hot electron devices for enhancement of surface reactivity by hot electrons

    DEFF Research Database (Denmark)

    Thomsen, Lasse Bjørchmar

    A Metal-Insulator-Semiconductor (MIS) based device is developed for investigation of hot electron enhanced chemistry. A model of the device is presented explaining the key concepts of the functionality and the character- istics. The MIS hot electron emitter is fabricated using cleanroom technology...... and the process sequence is described. An Ultra High Vacuum (UHV) setup is modified to facilitate experiments with electron emission from the MIS hot electron emitters and hot electron chemistry. Simulations show the importance of keeping tunnel barrier roughness to an absolute minimum. The tunnel oxide...... to be an important energy loss center for the electrons tunneling through the oxide lowering the emission e±ciency of a factor of 10 for a 1 nm Ti layer thickness. Electron emission is observed under ambient pressure conditions and in up to 2 bars of Ar. 2 bar Ar decrease the emission current by an order...

  4. Evaporation heat transfer of hot water from horizontal free service

    International Nuclear Information System (INIS)

    Koizumi, Y.; Ebihara, Y.; Hirota, T.; Murase, M.

    2011-01-01

    Evaporation heat transfer from the hot water flow to the cold air flow in a horizontal duct was examined. Hot water was in the range of 35 o C ~ 65 o C. Cold air was approximately 25 o C. The air velocity was varied from 0.0656 m/s ~ 1.41 m/s. The heat transfer rate from the water flow to the air flow became large with an increase in the air velocity. The higher the water temperature was, the larger the heat transfer rate was. When the total heat flux from water to the air flow is divided into two terms; the evaporation term and the forced flow convection term, the evaporation term dominate main part and that is about 90 ~ 80 % of the total heat flux. The measured values of the evaporation term and the forced flow convection term were larger than the predicted because of the effect of the diffusion of evaporated vapor. The correlation to predict the heat transfer from the hot water flow to the cold air flow with the evaporation was developed by modifying the laminar flow mass transfer correlation and the laminar forced convection heat transfer correlation. Good results were obtained. (author)

  5. Evaporation heat transfer of hot water from horizontal free service

    Energy Technology Data Exchange (ETDEWEB)

    Koizumi, Y.; Ebihara, Y.; Hirota, T. [Shinshu Univ., Ueda, Nagano (Japan); Murase, M. [INSS, Mihama-cho, Fukui (Japan)

    2011-07-01

    Evaporation heat transfer from the hot water flow to the cold air flow in a horizontal duct was examined. Hot water was in the range of 35{sup o}C ~ 65{sup o}C. Cold air was approximately 25{sup o}C. The air velocity was varied from 0.0656 m/s ~ 1.41 m/s. The heat transfer rate from the water flow to the air flow became large with an increase in the air velocity. The higher the water temperature was, the larger the heat transfer rate was. When the total heat flux from water to the air flow is divided into two terms; the evaporation term and the forced flow convection term, the evaporation term dominate main part and that is about 90 ~ 80 % of the total heat flux. The measured values of the evaporation term and the forced flow convection term were larger than the predicted because of the effect of the diffusion of evaporated vapor. The correlation to predict the heat transfer from the hot water flow to the cold air flow with the evaporation was developed by modifying the laminar flow mass transfer correlation and the laminar forced convection heat transfer correlation. Good results were obtained. (author)

  6. Recent trend of administration on hot springs

    Energy Technology Data Exchange (ETDEWEB)

    Okubo, Shigeru [Environment Agency, Tokyo (Japan)

    1989-01-01

    The Environmental Agency exercises jurisdiction over Hot Spring Act, and plans to protect the source of the hot spring and to utilize it appropriately. From the aspect of utilization, hot springs are widely used as a means to remedy chronic diseases and tourist spots besides places for recuperation and repose. Statistics on Japanese hot springs showed that the number of hot spring spots and utilized-fountainhead increased in 1987, compared with the number in 1986. Considering the utilized-headspring, the number of naturally well-out springs has stabilized for 10 years while power-operated springs have increased. This is because the demand of hot springs has grown as the number of users has increased. Another reason is to keep the amount of hot water by setting up the power facility as the welled-out amount has decreased. Major point of recent administration on the hot spring is to permit excavation and utilization of hot springs. Designation of National hot spring health resorts started in 1954 in order to ensure the effective and original use of hot springs and to promote the public use of them, for the purpose of arranging the sound circumstances of hot springs. By 1988, 76 places were designated. 4 figs., 3 tabs.

  7. What masses for Cepheids

    International Nuclear Information System (INIS)

    Davis, C.G.

    To understand the evolution of giant stars, it is important to pin down the masses for Cepheids. The 7- to 10-day bump Cepheids imply lower than evolutionary mass (60%). Recent theoretical work, though, indicates that for Cepheids with periods of 15 to 16 days, the best understanding of the light curves results from using evolutionary masses

  8. Determination of radial profile of ICF hot spot's state by multi-objective parameters optimization

    International Nuclear Information System (INIS)

    Dong Jianjun; Deng Bo; Cao Zhurong; Ding Yongkun; Jiang Shaoen

    2014-01-01

    A method using multi-objective parameters optimization is presented to determine the radial profile of hot spot temperature and density. And a parameter space which contain five variables: the temperatures at center and the interface of fuel and remain ablator, the maximum model density of remain ablator, the mass ratio of remain ablator to initial ablator and the position of interface between fuel and the remain ablator, is used to described the hot spot radial temperature and density. Two objective functions are set as the variances of normalized intensity profile from experiment X-ray images and the theory calculation. Another objective function is set as the variance of experiment average temperature of hot spot and the average temperature calculated by theoretical model. The optimized parameters are obtained by multi-objective genetic algorithm searching for the five dimension parameter space, thereby the optimized radial temperature and density profiles can be determined. The radial temperature and density profiles of hot spot by experiment data measured by KB microscope cooperating with X-ray film are presented. It is observed that the temperature profile is strongly correlated to the objective functions. (authors)

  9. Computational Prediction of Hot Spot Residues

    Science.gov (United States)

    Morrow, John Kenneth; Zhang, Shuxing

    2013-01-01

    Most biological processes involve multiple proteins interacting with each other. It has been recently discovered that certain residues in these protein-protein interactions, which are called hot spots, contribute more significantly to binding affinity than others. Hot spot residues have unique and diverse energetic properties that make them challenging yet important targets in the modulation of protein-protein complexes. Design of therapeutic agents that interact with hot spot residues has proven to be a valid methodology in disrupting unwanted protein-protein interactions. Using biological methods to determine which residues are hot spots can be costly and time consuming. Recent advances in computational approaches to predict hot spots have incorporated a myriad of features, and have shown increasing predictive successes. Here we review the state of knowledge around protein-protein interactions, hot spots, and give an overview of multiple in silico prediction techniques of hot spot residues. PMID:22316154

  10. Light, rest mass and electric charge quanta all formed by neutrinos?

    Science.gov (United States)

    Chen, Shao-Guang

    In high energy physics experiments the electric charge and rest mass of particles can commonly transform into the photons, vice versa. Its reason QFT can only give a vague answer: based on the particle creation and annihilation operators. There are not more clear answers or conjecture? At least, light, electric charge and rest mass should have a collective structure component, if not, the transformation is unable understanding. An elementary answer is that neutrino and antineutrino as their collective structure component. In the paper ‘Chen Qiliang & Wang Bin, The formation and characteristics of Chen Shaoguang's formula, China Science &Technology Overview 127101-103 (2011)’, the lowest energy state vertical polarized left spin 1/2 neutrino and right spin 1/2 antineutrino are just the left, right advance unit quanta la _{0}nuυ, ra nuυ _{0} and left, right back unit quanta lb (0) nuυ, rb nuυ (0) , it again compose into spin 1 unit photon la-ra _{0}nuυnuυ _{0} and back-photon lb-rb (0) nuυnuυ (0) , spin 0 unit rest mass ra-rb nuυ _{0}nuυ (0) and anti-mass la-lb _{0}nuυ (0) nuυ, spin 0 unit positive charge la-rb _{0}nuυnuυ (0) and negative charge ra-lb nuυ _{0} (0) nuυ. The physical vacuum is the even collocation of non-combinational nuυ _{0} or _{0}nuυ. It accord to the high energy physics experimental results of the transformation among the photons, masses quanta and charges quanta. In my paper ‘Quanta turn-advance ism, China Science && Technology Overview 131 192-210 (2011)’, QFT four-dimensional uncertainty principle and momentum-energy conservation law had been generalized as a five-dimensional equations: de Broglie wavelength as a position vector \\underline{q}= (i c t, r, s), momentum \\underline{P} = (i E / c, P, U c), \\underline{q} = i h / \\underline{P}, \\underline{q} \\underline{q} = 0, \\underline{P} \\underline{P} = 0, Sigma∑ \\underline{P} = \\underline{P} (0) . The five-dimensional time-space-spin had been quantized as a

  11. Positive, Neutral, and Negative Mass-Charges in General Relativity

    Directory of Open Access Journals (Sweden)

    Borissova L.

    2006-07-01

    Full Text Available As shown, any four-dimensional proper vector has two observable projections onto time line, attributed to our world and the mirror world (for a mass-bearing particle, the projections posses are attributed to positive and negative mass-charges. As predicted, there should be a class of neutrally mass-charged particles that inhabit neither our world nor the mirror world. Inside the space-time area (membrane the space rotates at the light speed, and all particles move at as well the light speed. So, the predicted particles of the neutrally mass-charged class should seem as light-like vortices.

  12. A Secular Resonant Origin for the Loneliness of Hot Jupiters

    Science.gov (United States)

    Spalding, Christopher; Batygin, Konstantin

    2017-09-01

    Despite decades of inquiry, the origin of giant planets residing within a few tenths of an astronomical unit from their host stars remains unclear. Traditionally, these objects are thought to have formed further out before subsequently migrating inwards. However, the necessity of migration has been recently called into question with the emergence of in situ formation models of close-in giant planets. Observational characterization of the transiting subsample of close-in giants has revealed that “warm” Jupiters, possessing orbital periods longer than roughly 10 days more often possess close-in, co-transiting planetary companions than shorter period “hot” Jupiters, that are usually lonely. This finding has previously been interpreted as evidence that smooth, early migration or in situ formation gave rise to warm Jupiter-hosting systems, whereas more violent, post-disk migration pathways sculpted hot Jupiter-hosting systems. In this work, we demonstrate that both classes of planet may arise via early migration or in situ conglomeration, but that the enhanced loneliness of hot Jupiters arises due to a secular resonant interaction with the stellar quadrupole moment. Such an interaction tilts the orbits of exterior, lower-mass planets, removing them from transit surveys where the hot Jupiter is detected. Warm Jupiter-hosting systems, in contrast, retain their coplanarity due to the weaker influence of the host star’s quadrupolar potential relative to planet-disk interactions. In this way, hot Jupiters and warm Jupiters are placed within a unified theoretical framework that may be readily validated or falsified using data from upcoming missions, such as TESS.

  13. Hot Spots and Hot Moments of Nitrogen in a Riparian Corridor

    Science.gov (United States)

    Dwivedi, Dipankar; Arora, Bhavna; Steefel, Carl I.; Dafflon, Baptiste; Versteeg, Roelof

    2018-01-01

    We use 3-D high-resolution reactive transport modeling to investigate whether the spatial distribution of organic-carbon-rich and chemically reduced sediments located in the riparian zone and temporal variability in groundwater flow direction impact the formation and distribution of nitrogen hot spots (regions that exhibit higher reaction rates when compared to other locations nearby) and hot moments (times that exhibit high reaction rates as compared to longer intervening time periods) within the Rifle floodplain in Colorado. Groundwater flows primarily toward the Colorado River from the floodplain but changes direction at times of high river stage. The result is that oxic river water infiltrates the Rifle floodplain during these relatively short-term events. Simulation results indicate that episodic rainfall in the summer season leads to the formation of nitrogen hot moments associated with Colorado River rise and resulting river infiltration into the floodplain. The results further demonstrate that the naturally reduced zones (NRZs) present in sediments of the Rifle floodplain have a higher potential for nitrate removal, approximately 70% greater than non-NRZs for typical hydrological conditions. During river water infiltration, nitrate reduction capacity remains the same within the NRZs, however, these conditions impact non-NRZs to a greater extent (approximately 95% less nitrate removal). Model simulations indicate chemolithoautotrophs are primarily responsible for the removal of nitrate in the Rifle floodplain. These nitrogen hot spots and hot moments are sustained by microbial respiration and the chemolithoautotrophic oxidation of reduced minerals in the riparian zone.

  14. THE MAGELLANIC STREAM: BREAK-UP AND ACCRETION ONTO THE HOT GALACTIC CORONA

    Energy Technology Data Exchange (ETDEWEB)

    Tepper-García, Thor; Bland-Hawthorn, Joss [Sydney Institute for Astronomy, School of Physics, University of Sydney, NSW 2006 (Australia); Sutherland, Ralph S. [Mount Stromlo Observatory, Australia National University, Woden, ACT 2611 (Australia)

    2015-11-10

    The Magellanic H i Stream (≈2 × 10{sup 9} M{sub ⊙} [d/55 kpc]{sup 2}) encircling the Galaxy at a distance d is arguably the most important tracer of what happens to gas accreting onto a disk galaxy. Recent observations reveal that the Stream’s mass is in fact dominated (3:1) by its ionized component. Here we revisit the origin of the mysterious Hα recombination emission observed along much of its length that is overly bright (∼150–200 mR) for the known Galactic ultraviolet (UV) background (≈20–40 mR [d/55 kpc]{sup −2}). In an earlier model, we proposed that a slow shock cascade was operating along the Stream due to its interaction with the extended Galactic hot corona. We find that for a smooth coronal density profile, this model can explain the bright Hα emission if the coronal density satisfies 2 × 10{sup −4} < (n/cm{sup −3}) < 4 × 10{sup −4} at d = 55 kpc. But in view of updated parameters for the Galactic halo and mounting evidence that most of the Stream must lie far beyond the Magellanic Clouds (d > 55 kpc), we revisit the shock cascade model in detail. At lower densities, the H i gas is broken down by the shock cascade but mostly mixes with the hot corona without significant recombination. At higher densities, the hot coronal mass (including the other baryonic components) exceeds the baryon budget of the Galaxy. If the Hα emission arises from the shock cascade, the upper limit on the smooth coronal density constrains the Stream’s mean distance to ≲75 kpc. If, as some models indicate, the Stream is even further out, either the shock cascade is operating in a regime where the corona is substantially mass-loaded with recent gas debris, or an entirely different ionization mechanism is responsible.

  15. Lighting consumption and buildings’ energy certifications in Italy

    International Nuclear Information System (INIS)

    Blaso, Laura; Loverso, Valerio R.M; Mutani, Guglielmina

    2015-01-01

    This paper discusses the procedure prescribed by Italian Standards to account the heat gains due to artificial lighting in the calculation of the energy performance indices for a building. A new procedure, based on the Lighting Energy Numerical Indicator (LENI), is proposed. This consists of three steps: i) internal gains from lighting are calculated accounting for day lighting and controls; ii) these gains are summed to the internal heat gains from occupants and appliances; iii) the global heat gains are used to calculate the energy performance indices (for lighting, cooling, heating and hot water production) for an office building following the Italian Technical Standards. The case-study used is the building hosting the Department of Energy at Politecnico di Torino. The building was assumed to be located in Turin and Palermo, and the use of a manual on/off switch and of a photo dimming sensor was also compared. For each configuration, all energy performance indices were calculated comparing standard and new approach [it

  16. Determination of diffusion coefficients of hydrogen and deuterium in Zr–2.5%Nb pressure tube material using hot vacuum extraction-quadrupole mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Shrivastava, Komal Chandra, E-mail: komal@barc.gov.in [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Kulkarni, A.S.; Ramanjaneyulu, P.S. [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Sunil, Saurav [Mechanical Metallurgy Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Saxena, M.K. [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Singh, R.N. [Mechanical Metallurgy Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India); Tomar, B.S.; Ramakumar, K.L. [Radioanalytical Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

    2015-06-15

    The diffusion coefficients of hydrogen and deuterium in Zr–2.5%Nb alloy were measured in the temperature range 523 to 673 K, employing hot vacuum extraction-quadrupole mass spectrometry (HVE-QMS). One end of the Zr–2.5%Nb alloy specimens was charged electrolytically with the desired hydrogen isotope. After annealing at different temperatures for a predetermined time, the specimens were cut into thin slices, which were analyzed for their H{sub 2}/D{sub 2} content using the HVE-QMS technique. The depth profile data were fitted into the equation representing the solution of Fick’s second law of diffusion. The activation energy of hydrogen/deuterium diffusion was obtained from the Arrhenius relation between the diffusion coefficient and temperature. The temperature dependent diffusion coefficient can be represented as D{sub H} = 1.41 × 10{sup −7} exp(−36,000/RT) and D{sub D} = 6.16 × 10{sup −8} exp(−35,262/RT) for hydrogen and deuterium, respectively.

  17. Hot Spot Removal System: System description

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-09-01

    Hazardous wastes contaminated with radionuclides, chemicals, and explosives exist across the Department of Energy complex and need to be remediated due to environmental concerns. Currently, an opportunity is being developed to dramatically reduce remediation costs and to assist in the acceleration of schedules associated with these wastes by deploying a Hot Spot Removal System. Removing the hot spot from the waste site will remove risk driver(s) and enable another, more cost effective process/option/remedial alternative (i.e., capping) to be applied to the remainder of the site. The Hot Spot Removal System consists of a suite of technologies that will be utilized to locate and remove source terms. Components of the system can also be used in a variety of other cleanup activities. This Hot Spot Removal System Description document presents technologies that were considered for possible inclusion in the Hot Spot Removal System, technologies made available to the Hot Spot Removal System, industrial interest in the Hot Spot Removal System`s subsystems, the schedule required for the Hot Spot Removal System, the evaluation of the relevant technologies, and the recommendations for equipment and technologies as stated in the Plan section.

  18. Hot Spot Removal System: System description

    International Nuclear Information System (INIS)

    1997-09-01

    Hazardous wastes contaminated with radionuclides, chemicals, and explosives exist across the Department of Energy complex and need to be remediated due to environmental concerns. Currently, an opportunity is being developed to dramatically reduce remediation costs and to assist in the acceleration of schedules associated with these wastes by deploying a Hot Spot Removal System. Removing the hot spot from the waste site will remove risk driver(s) and enable another, more cost effective process/option/remedial alternative (i.e., capping) to be applied to the remainder of the site. The Hot Spot Removal System consists of a suite of technologies that will be utilized to locate and remove source terms. Components of the system can also be used in a variety of other cleanup activities. This Hot Spot Removal System Description document presents technologies that were considered for possible inclusion in the Hot Spot Removal System, technologies made available to the Hot Spot Removal System, industrial interest in the Hot Spot Removal System''s subsystems, the schedule required for the Hot Spot Removal System, the evaluation of the relevant technologies, and the recommendations for equipment and technologies as stated in the Plan section

  19. Light weakly interacting massive particles

    Science.gov (United States)

    Gelmini, Graciela B.

    2017-08-01

    Light weakly interacting massive particles (WIMPs) are dark matter particle candidates with weak scale interaction with the known particles, and mass in the GeV to tens of GeV range. Hints of light WIMPs have appeared in several dark matter searches in the last decade. The unprecedented possible coincidence into tantalizingly close regions of mass and cross section of four separate direct detection experimental hints and a potential indirect detection signal in gamma rays from the galactic center, aroused considerable interest in our field. Even if these hints did not so far result in a discovery, they have had a significant impact in our field. Here we review the evidence for and against light WIMPs as dark matter candidates and discuss future relevant experiments and observations.

  20. Ponderomotive and thermal filamentation of laser light

    International Nuclear Information System (INIS)

    Kruer, W.L.

    1985-01-01

    As targets are irradiated with longer, more energetic pulses of laser light, longer-scalelength plasmas are produced. Filamentation is a potentially important process in such plasmas. In this instability, perturbations in the intensity profile of an incident light beam grow in amplitude, causing the beam to break up into intense filaments. The instability arises when a local increase in the light intensity creates a depression in plasma density either directly, via the ponderomotive force, or indirectly, via enhanced collisional absorption and subsequent plasma expansion. The density depression refracts the light into the lower-density region, enhancing the intensity perturbations. The instability is termed either ponderomotive or thermal filamentation, depending on which mechanism generates the density depression. The analogous process involving the entire beam is called self-focusing. Filamentation can significantly affect laser-plasma coupling. Intensity enhancements can introduce or modify other instabilities, change the location of the energy deposition, and possibly aggravate deleterious collective effects such as hot-electron generation