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Sample records for extrasolar late heavy

  1. The terrestrial record of Late Heavy Bombardment

    Science.gov (United States)

    Lowe, Donald R.; Byerly, Gary R.

    2018-04-01

    Until recently, the known impact record of the early Solar System lay exclusively on the surfaces of the Moon, Mars, and other bodies where it has not been erased by later weathering, erosion, impact gardening, and/or tectonism. Study of the cratered surfaces of these bodies led to the concept of the Late Heavy Bombardment (LHB), an interval from about 4.1 to 3.8 billion years ago (Ga) during which the surfaces of the planets and moons in the inner Solar System were subject to unusually high rates of bombardment followed by a decline to present low impact rates by about 3.5 Ga. Over the past 30 years, however, it has become apparent that there is a terrestrial record of large impacts from at least 3.47 to 3.22 Ga and from 2.63 to 2.49 Ga. The present paper explores the earlier of these impact records, providing details about the nature of the 8 known ejecta layers that constitute the evidence for large terrestrial impacts during the earlier of these intervals, the inferred size of the impactors, and the potential effects of these impacts on crustal development and life. The existence of this record implies that LHB did not end abruptly at 3.8-3.7 Ga but rather that high impact rates, either continuous or as impact clusters, persisted until at least the close of the Archean at 2.5 Ga. It implies that the shift from external, impact-related controls on the long-term development of the surface system on the Earth to more internal, geodynamic controls may have occurred much later in geologic history than has been supposed previously.

  2. Extrasolar Planetary Imaging Coronagraph

    Science.gov (United States)

    Clampin, M.

    2007-06-01

    The Extrasolar Planetary Imaging Coronagraph (EPIC) is a proposed NASA Discovery mission to image and characterize extrasolar giant planets in orbits with semi-major axes between 2 and 10 AU. EPIC will provide insights into the physical nature of a variety of planets in other solar systems complimenting radial velocity (RV) and astrometric planet searches. It will detect and characterize the atmospheres of planets identified by radial velocity surveys, determine orbital inclinations and masses, characterize the atmospheres around A and F type stars which cannot be found with RV techniques, and observe the inner spatial structure and colors of debris disks. The robust mission design is simple and flexible ensuring mission success while minimizing cost and risk. The science payload consists of a heritage optical telescope assembly (OTA), and visible nulling coronagraph (VNC) instrument.

  3. Extrasolar Planets in the Classroom

    Science.gov (United States)

    George, Samuel J.

    2011-01-01

    The field of extrasolar planets is still, in comparison with other astrophysical topics, in its infancy. There have been about 300 or so extrasolar planets detected and their detection has been accomplished by various different techniques. Here we present a simple laboratory experiment to show how planets are detected using the transit technique.…

  4. Evidence Supporting an Early as Well as Late Heavy Bombardment on the Moon

    Science.gov (United States)

    Frey, Herbert

    2015-01-01

    Evidence supporting an intense early bombardment on the Moon in addition to the traditional Late Heavy Bombardment at approx. 4 BY ago include the distribution of N(50) Crater Retention Ages (CRAs) for candidate basins, a variety of absolute age scenarios for both a "young" and an "old" Nectaris age, and the decreasing contrasts in both topographic relief and Bouguer gravity with increasing CRA.

  5. Taxonomy of the extrasolar planet.

    Science.gov (United States)

    Plávalová, Eva

    2012-04-01

    When a star is described as a spectral class G2V, we know that the star is similar to our Sun. We know its approximate mass, temperature, age, and size. When working with an extrasolar planet database, it is very useful to have a taxonomy scale (classification) such as, for example, the Harvard classification for stars. The taxonomy has to be easily interpreted and present the most relevant information about extrasolar planets. I propose an extrasolar planet taxonomy scale with four parameters. The first parameter concerns the mass of an extrasolar planet in the form of units of the mass of other known planets, where M represents the mass of Mercury, E that of Earth, N Neptune, and J Jupiter. The second parameter is the planet's distance from its parent star (semimajor axis) described in a logarithm with base 10. The third parameter is the mean Dyson temperature of the extrasolar planet, for which I established four main temperature classes: F represents the Freezing class, W the Water class, G the Gaseous class, and R the Roasters class. I devised one additional class, however: P, the Pulsar class, which concerns extrasolar planets orbiting pulsar stars. The fourth parameter is eccentricity. If the attributes of the surface of the extrasolar planet are known, we are able to establish this additional parameter where t represents a terrestrial planet, g a gaseous planet, and i an ice planet. According to this taxonomy scale, for example, Earth is 1E0W0t, Neptune is 1N1.5F0i, and extrasolar planet 55 Cnc e is 9E-1.8R1.

  6. HCN Production via Impact Ejecta Reentry During the Late Heavy Bombardment

    Science.gov (United States)

    Parkos, Devon; Pikus, Aaron; Alexeenko, Alina; Melosh, H. Jay

    2018-04-01

    Major impact events have shaped the Earth as we know it. The Late Heavy Bombardment is of particular interest because it immediately precedes the first evidence of life. The reentry of impact ejecta creates numerous chemical by-products, including biotic precursors such as HCN. This work examines the production of HCN during the Late Heavy Bombardment in more detail. We stochastically simulate the range of impacts on the early Earth and use models developed from existing studies to predict the corresponding ejecta properties. Using multiphase flow methods and finite-rate equilibrium chemistry, we then find the HCN production due to the resulting atmospheric heating. We use Direct Simulation Monte Carlo to develop a correction factor to account for increased yields due to thermochemical nonequilibrium. We then model 1-D atmospheric turbulent diffusion to find the time accurate transport of HCN to lower altitudes and ultimately surface water. Existing works estimate the necessary HCN molarity threshold to promote polymerization that is 0.01 M. For a mixing depth of 100 m, we find that the Late Heavy Bombardment will produce at least one impact event above this threshold with probability 24.1% for an oxidized atmosphere and 56.3% for a partially reduced atmosphere. For a mixing depth of 10 m, the probability is 79.5% for an oxidized atmosphere and 96.9% for a partially reduced atmosphere. Therefore, Late Heavy Bombardment impact ejecta is likely an HCN source sufficient for polymerization in shallow bodies of water, particularly if the atmosphere were in a partially reduced state.

  7. Thermal escape from extrasolar giant planets.

    Science.gov (United States)

    Koskinen, Tommi T; Lavvas, Panayotis; Harris, Matthew J; Yelle, Roger V

    2014-04-28

    The detection of hot atomic hydrogen and heavy atoms and ions at high altitudes around close-in extrasolar giant planets (EGPs) such as HD209458b implies that these planets have hot and rapidly escaping atmospheres that extend to several planetary radii. These characteristics, however, cannot be generalized to all close-in EGPs. The thermal escape mechanism and mass loss rate from EGPs depend on a complex interplay between photochemistry and radiative transfer driven by the stellar UV radiation. In this study, we explore how these processes change under different levels of irradiation on giant planets with different characteristics. We confirm that there are two distinct regimes of thermal escape from EGPs, and that the transition between these regimes is relatively sharp. Our results have implications for thermal mass loss rates from different EGPs that we discuss in the context of currently known planets and the detectability of their upper atmospheres.

  8. Extrasolar Planetary Imaging Coronagraph (EPIC)

    Science.gov (United States)

    Clampin, Mark

    2009-01-01

    The Extrasolar Planetary Imaging Coronagraph (EPIC) is a proposed NASA Exoplanet Probe mission to image and characterize extrasolar giant planets. EPIC will provide insights into the physical nature and architecture of a variety of planets in other solar systems. Initially, it will detect and characterize the atmospheres of planets identified by radial velocity surveys, determine orbital inclinations and masses and characterize the atmospheres around A and F type stars which cannot be found with RV techniques. It will also observe the inner spatial structure of exozodiacal disks. EPIC has a heliocentric Earth trailing drift-away orbit, with a 5 year mission lifetime. The robust mission design is simple and flexible ensuring mission success while minimizing cost and risk. The science payload consists of a heritage optical telescope assembly (OTA), and visible nulling coronagraph (VNC) instrument. The instrument achieves a contrast ratio of 10^9 over a 5 arcsecond field-of-view with an unprecedented inner working angle of 0.13 arcseconds over the spectral range of 440-880 nm. The telescope is a 1.65 meter off-axis Cassegrain with an OTA wavefront error of lambda/9, which when coupled to the VNC greatly reduces the requirements on the large scale optics.

  9. EVIDENCE FOR GAS FROM A DISINTEGRATING EXTRASOLAR ASTEROID

    International Nuclear Information System (INIS)

    Xu, S.; Jura, M.; Zuckerman, B.; Dufour, P.

    2016-01-01

    We report high-resolution spectroscopic observations of WD 1145+017—a white dwarf that was recently found to be transitted by multiple asteroid-sized objects within its tidal radius. We discovered numerous circumstellar absorption lines with linewidths of ∼300 km s −1 from Mg, Ca, Ti, Cr, Mn, Fe, and Ni, possibly from several gas streams produced by collisions among the actively disintegrating objects. The atmosphere of WD 1145+017 is polluted with 11 heavy elements, including O, Mg, Al, Si, Ca, Ti, V:, Cr, Mn, Fe, and Ni. Evidently, we are witnessing the active disintegration and subsequent accretion of an extrasolar asteroid

  10. EVIDENCE FOR GAS FROM A DISINTEGRATING EXTRASOLAR ASTEROID

    Energy Technology Data Exchange (ETDEWEB)

    Xu, S. [European Southern Observatory, Karl-Schwarzschild-Straße 2, D-85748 Garching (Germany); Jura, M.; Zuckerman, B. [Department of Physics and Astronomy, University of California, Los Angeles CA 90095-1562 (United States); Dufour, P., E-mail: sxu@eso.org, E-mail: jura@astro.ucla.edu, E-mail: ben@astro.ucla.edu, E-mail: dufourpa@astro.umontreal.ca [Institut de Recherche sur les Exoplanètes (iREx), Université de Montréal, Montréal, QC H3C 3J7 (Canada)

    2016-01-10

    We report high-resolution spectroscopic observations of WD 1145+017—a white dwarf that was recently found to be transitted by multiple asteroid-sized objects within its tidal radius. We discovered numerous circumstellar absorption lines with linewidths of ∼300 km s{sup −1} from Mg, Ca, Ti, Cr, Mn, Fe, and Ni, possibly from several gas streams produced by collisions among the actively disintegrating objects. The atmosphere of WD 1145+017 is polluted with 11 heavy elements, including O, Mg, Al, Si, Ca, Ti, V:, Cr, Mn, Fe, and Ni. Evidently, we are witnessing the active disintegration and subsequent accretion of an extrasolar asteroid.

  11. Observed properties of extrasolar planets.

    Science.gov (United States)

    Howard, Andrew W

    2013-05-03

    Observational surveys for extrasolar planets probe the diverse outcomes of planet formation and evolution. These surveys measure the frequency of planets with different masses, sizes, orbital characteristics, and host star properties. Small planets between the sizes of Earth and Neptune substantially outnumber Jupiter-sized planets. The survey measurements support the core accretion model, in which planets form by the accumulation of solids and then gas in protoplanetary disks. The diversity of exoplanetary characteristics demonstrates that most of the gross features of the solar system are one outcome in a continuum of possibilities. The most common class of planetary system detectable today consists of one or more planets approximately one to three times Earth's size orbiting within a fraction of the Earth-Sun distance.

  12. Electrodynamics on extrasolar giant planets

    Energy Technology Data Exchange (ETDEWEB)

    Koskinen, T. T.; Yelle, R. V. [Lunar and Planetary Laboratory, University of Arizona, 1629 East University Boulevard, Tucson, AZ 85721-0092 (United States); Lavvas, P. [Groupe de Spectroscopie Moléculaire et Atmosphérique UMR CNRS 7331, Université Reims Champagne-Ardenne, F-51687 Reims (France); Cho, J. Y-K., E-mail: tommi@lpl.arizona.edu [Astronomy Unit, School of Mathematical Sciences, Queen Mary, University of London, Mile End Road, London E1 4NS (United Kingdom)

    2014-11-20

    Strong ionization on close-in extrasolar giant planets (EGPs) suggests that their atmospheres may be affected by ion drag and resistive heating arising from wind-driven electrodynamics. Recent models of ion drag on these planets, however, are based on thermal ionization only and do not include the upper atmosphere above the 1 mbar level. These models are also based on simplified equations of resistive magnetohydrodynamics that are not always valid in extrasolar planet atmospheres. We show that photoionization dominates over thermal ionization over much of the dayside atmosphere above the 100 mbar level, creating an upper ionosphere dominated by ionization of H and He and a lower ionosphere dominated by ionization of metals such as Na, K, and Mg. The resulting dayside electron densities on close-in exoplanets are higher than those encountered in any planetary ionosphere of the solar system, and the conductivities are comparable to the chromosphere of the Sun. Based on these results and assumed magnetic fields, we constrain the conductivity regimes on close-in EGPs and use a generalized Ohm's law to study the basic effects of electrodynamics in their atmospheres. We find that ion drag is important above the 10 mbar level where it can also significantly alter the energy balance through resistive heating. Due to frequent collisions of the electrons and ions with the neutral atmosphere, however, ion drag is largely negligible in the lower atmosphere below the 10 mbar level for a reasonable range of planetary magnetic moments. We find that the atmospheric conductivity decreases by several orders of magnitude in the night side of tidally locked planets, leading to a potentially interesting large-scale dichotomy in electrodynamics between the day and night sides. A combined approach that relies on UV observations of the upper atmosphere, phase curve and Doppler measurements of global dynamics, and visual transit observations to probe the alkali metals can potentially

  13. Identifying Risk Factors for Late-Onset (50+) Alcohol Use Disorder and Heavy Drinking: A Systematic Review.

    Science.gov (United States)

    Emiliussen, Jakob; Nielsen, Anette Søgaard; Andersen, Kjeld

    2017-10-15

    This systematic review seeks to expand the description and understanding of late-onset AUD and asks "Which risk factors have been reported for late-onset heavy drinking and AUD?" Using PRISMA guidelines, a literature review and search was performed on May 19, 2015 using the following databases: MEDLINE, EMBASE, PubMed, and PsychInfo. Nine studies were included in the final review. The search revealed that only very few studies have been conducted. Hence, the evidence is limited but suggests that stress, role/identity loss, and friends' approval of drinking are associated with an increased risk for late-onset AUD or heavy drinking, whereas retirement, death of a spouse or a close relative does not increase the risk. Inherent differences in measurements and methodologies precluded a meta-analysis. Therefore, the results presented here are descriptive in nature. Most studies base their conclusions on a certain preconception of older adults with alcohol problems, which leads to a row of circular arguments. The factors that have been measured seem to have changed over time. There has been a lack of focus on the field of late-onset AUD since the 1970s, which possibly has led to misrepresentations and preconceptions on the complex nature of late-onset AUD. There is limited evidence for any specific risk factor for late-onset AUD or heavy drinking. We suggest the adoption of a qualitative approach to uncover what is intrinsic to late-onset AUD followed by quantitative studies with more agreement on methods and definitions.

  14. The Radiometric Bode's law and Extrasolar Planets

    National Research Council Canada - National Science Library

    Lazio, T. J; Farrell, W. M; Dietrick, Jill; Greenlees, Elizabeth; Hogan, Emily; Jones, Christopher; Hennig, L. A

    2004-01-01

    We predict the radio flux densities of the extrasolar planets in the current census, making use of an empirical relation the radiometric Bode's law determined from the five "magnetic" planets in the solar system...

  15. Microbial habitability of the Hadean Earth during the late heavy bombardment.

    Science.gov (United States)

    Abramov, Oleg; Mojzsis, Stephen J

    2009-05-21

    Lunar rocks and impact melts, lunar and asteroidal meteorites, and an ancient martian meteorite record thermal metamorphic events with ages that group around and/or do not exceed 3.9 Gyr. That such a diverse suite of solar system materials share this feature is interpreted to be the result of a post-primary-accretion cataclysmic spike in the number of impacts commonly referred to as the late heavy bombardment (LHB). Despite its obvious significance to the preservation of crust and the survivability of an emergent biosphere, the thermal effects of this bombardment on the young Earth remain poorly constrained. Here we report numerical models constructed to probe the degree of thermal metamorphism in the crust in the effort to recreate the effect of the LHB on the Earth as a whole; outputs were used to assess habitable volumes of crust for a possible near-surface and subsurface primordial microbial biosphere. Our analysis shows that there is no plausible situation in which the habitable zone was fully sterilized on Earth, at least since the termination of primary accretion of the planets and the postulated impact origin of the Moon. Our results explain the root location of hyperthermophilic bacteria in the phylogenetic tree for 16S small-subunit ribosomal RNA, and bode well for the persistence of microbial biospheres even on planetary bodies strongly reworked by impacts.

  16. Microbial habitability of the Hadean Earth during the late heavy bombardment

    Science.gov (United States)

    Abramov, Oleg; Mojzsis, Stephen J.

    2009-05-01

    Lunar rocks and impact melts, lunar and asteroidal meteorites, and an ancient martian meteorite record thermal metamorphic events with ages that group around and/or do not exceed 3.9Gyr. That such a diverse suite of solar system materials share this feature is interpreted to be the result of a post-primary-accretion cataclysmic spike in the number of impacts commonly referred to as the late heavy bombardment (LHB). Despite its obvious significance to the preservation of crust and the survivability of an emergent biosphere, the thermal effects of this bombardment on the young Earth remain poorly constrained. Here we report numerical models constructed to probe the degree of thermal metamorphism in the crust in the effort to recreate the effect of the LHB on the Earth as a whole; outputs were used to assess habitable volumes of crust for a possible near-surface and subsurface primordial microbial biosphere. Our analysis shows that there is no plausible situation in which the habitable zone was fully sterilized on Earth, at least since the termination of primary accretion of the planets and the postulated impact origin of the Moon. Our results explain the root location of hyperthermophilic bacteria in the phylogenetic tree for 16S small-subunit ribosomal RNA, and bode well for the persistence of microbial biospheres even on planetary bodies strongly reworked by impacts.

  17. Late Effects of Heavy Ion Irradiation on Ex Vivo Osteoblastogenesis and Cancellous Bone Microarchitecture

    Science.gov (United States)

    Tran, Luan Hoang; Alwood, Joshua; Kumar, Akhilesh; Limoli, C. L.; Globus, Ruth

    2012-01-01

    Prolonged spaceflight causes degeneration of skeletal tissue with incomplete recovery even after return to Earth. We hypothesize that heavy ion irradiation, a component of Galactic Cosmic Radiation, damages osteoblast progenitors and may contribute to bone loss during long duration space travel beyond the protection of the Earth's magnetosphere. Male, 16 week old C57BL6/J mice were exposed to high LET (56 Fe, 600MeV) radiation using either low (5 or 10cGy) or high (50 or 200cGy) doses at the NASA Space Radiation Lab and were euthanized 3 - 4, 7, or 35 days later. Bone structure was quantified by microcomputed tomography (6.8 micron pixel size) and marrow cell redox assessed using membrane permeable, free radical sensitive fluorogenic dyes. To assess osteoblastogenesis, adherent marrow cells were cultured ex vivo, then mineralized nodule formation quantified by imaging and gene expression analyzed by RT PCR. Interestingly, 3 - 4 days post exposure, fluorogenic dyes that reflect cytoplasmic generation of reactive nitrogen/oxygen species (DAF FM Diacetate or CM H2DCFDA) revealed irradiation (50cGy) reduced free radical generation (20-45%) compared to sham irradiated controls. Alternatively, use of a dye showing relative specificity for mitochondrial superoxide generation (MitoSOX) revealed an 88% increase compared to controls. One week after exposure, reactive oxygen/nitrogen levels remained lower(24%) relative to sham irradiated controls. After one month, high dose irradiation (200 cGy) caused an 86% decrement in ex vivo nodule formation and a 16-31% decrement in bone volume to total volume and trabecular number (50, 200cGy) compared to controls. High dose irradiation (200cGy) up regulated expression of a late osteoblast marker (BGLAP) and select genes related to oxidative metabolism (Catalase) and DNA damage repair (Gadd45). In contrast, lower doses (5, 10cGy) did not affect bone structure or ex vivo nodule formation, but did down regulate iNOS by 0.54 - 0.58 fold

  18. Characterizing the X-ray & Stellar Wind Environment in the ~1 Gyr Late Heavy Bombardment System Eta Corvi

    Science.gov (United States)

    Lisse, Carey

    2012-09-01

    We propose a 40 ksec ACIS-S observation of the 1 Gyr old system Eta Corvi, the site of an on-going Late Heavy Bombardment (Lisse et al. 2012), in order to determine the spectrum of x-ray radiation in the burgeoning system, its origin in the stellar coronae and circumstellar debris belts, and its impact on the water and organics recently delivered to a rocky planet in the terrestrial habitability zone.

  19. IRAC Monitoring of the Late Heavy Comet Bombardment in the eta Corvi System

    Science.gov (United States)

    Marengo, Massimo; Lisse, Carey; Stapelfeldt, Karl; Hulsebus, Alan

    2014-12-01

    The nearby sun-like star eta Corvi (F2V, d=18 pc, age =1.2 Gyr) has long been known to possess a bright, dusty Kuiper Belt that has now been resolved with Herschel PACS. A warm inner dust belt indicated by an IRAS 12 micron excess and has recently been resolved as a 3-AU scale structure by VLT observations. In 2012 Lisse et al. further characterized this warm dust using Spitzer IRS, identifying the signatures of ice, organics and silicate dust in this system's Terrestrial Habitability Zone (THZ). The system appears to be undergoing a Late Heavy Bombardment (LHB), delivering primitive, water- and organic-rich material from the Kuiper Belt to the THZ, at roughly the same relative age as the solar system's LHB. Our data also showed an upturn in the excess flux shortwards of 6 micron ? evidence for a surprisingly large amount of icy dust scattering in the inner system (fscat/fstar ~ 1.0%). This results is corroborated by our recent 2-5 micron NASA/IRTF SpeX spectroscopy. In 2012 we have obtained Spitzer/IRAC photometric data for the system, detecting the disk at 3.6 and 4.5 micron in two separate epochs, followed by a third epoch in 2013. We now propose to continue our photometric monitoring with 15 additional visits to be scheduled within cycle 11, in order to extend our temporal coverage to 4 years on a variety of timescales ranging from days, to weeks, to months. The proposed campaign will allow us to test the two competing hypothesis for the origin of the warm disk: (1) single collison event leading to the breakup of a large Kuiper Belt object in the system or (2) continual raining of small comets scattered towards the inner system.

  20. Ku70 is required for late B cell development and immunoglobulin heavy chain class switching.

    Science.gov (United States)

    Manis, J P; Gu, Y; Lansford, R; Sonoda, E; Ferrini, R; Davidson, L; Rajewsky, K; Alt, F W

    1998-06-15

    Immunoglobulin (Ig) heavy chain (HC) class switch recombination (CSR) is a late B cell process that involves intrachromosomal DNA rearrangement. Ku70 and Ku80 form a DNA end-binding complex required for DNA double strand break repair and V(D)J recombination. Ku70(-/-) (K70T) mice, like recombination activating gene (RAG)-1- or RAG-2-deficient (R1T or R2T) mice, have impaired B and T cell development at an early progenitor stage, which is thought to result at least in part from defective V(D)J recombination (Gu, Y., K.J. Seidl, G.A. Rathbun, C. Zhu, J.P. Manis, N. van der Stoep, L. Davidson, H.L. Cheng, J.M. Sekiguchi, K. Frank, et al. 1997. Immunity. 7:653-665; Ouyang, H., A. Nussenzweig, A. Kurimasa, V.C. Soares, X. Li, C. Cordon-Cardo, W. Li, N. Cheong, M. Nussenzweig, G. Iliakis, et al. 1997. J. Exp. Med. 186:921-929). Therefore, to examine the potential role of Ku70 in CSR, we generated K70T mice that carry a germline Ig HC locus in which the JH region was replaced with a functionally rearranged VH(D)JH and Ig lambda light chain transgene (referred to as K70T/HL mice). Previously, we have shown that B cells from R1T or R2T mice carrying these rearranged Ig genes (R1T/HL or R2T/HL mice) can undergo CSR to IgG isotypes (Lansford, R., J. Manis, E. Sonoda, K. Rajewsky, and F. Alt. 1998. Int. Immunol. 10:325-332). K70T/HL mice had significant numbers of peripheral surface IgM+ B cells, which generated serum IgM levels similar to those of R2T/HL mice. However, in contrast to R2T/HL mice, K70T/HL mice had no detectable serum IgG isotypes. In vitro culture of K70T/HL B cells with agents that induce CSR in normal or R2T/HL B cells did lead to the induction of germline CH transcripts, indicating that initial signaling pathways for CSR were intact in K70T/HL cells. However, treatment with such agents did not lead to detectable CSR by K70T/HL B cells, and instead, led to cell death within 72 h. We conclude that Ku70 is required for the generation of B cells that have

  1. Bioaccumulation of heavy metals in maricultured fish, Lates calcarifer (Barramudi), Lutjanus campechanus (red snapper) and Lutjanus griseus (grey snapper).

    Science.gov (United States)

    Nasyitah Sobihah, Nasri; Ahmad Zaharin, Aris; Khairul Nizam, Mohammad; Ley Juen, Looi; Kyoung-Woong, Kim

    2018-04-01

    Mariculture fish contains a rich source of protein, but some species may bioaccumulate high levels of heavy metals, making them unsafe for consumption. This study aims to identify heavy metal concentration in Lates calcarifer (Barramudi), Lutjanus campechanus (Red snapper) and Lutjanus griseus (Grey snapper). Three species of mariculture fish, namely, L. calcarifer, L. campechanus and L. griseus were collected for analyses of heavy metals. The concentration of heavy metal (As, Cd, Cu, Cr, Fe, Pb, Mn, Ni, Se, and Zn) was determined using inductive coupled plasma mass spectrometry (ICP-MS). The distribution of heavy metals mean concentration in muscle is Zn > Fe > As > Se > Cr > Cu > Mn > Pb > Ni > Cd for L. calcarifer, Fe > Zn > Cr > As > Ni > Mn > Se > Cu > Pb > Cd for L. campechanus and Fe > Zn > Cr > Ni > Se > Cu > As > Mn > Pb > Cd for L. griseus. Among all of the species under investigation, the highest concentration of Fe was found in the muscle tissue of L. campechanus (19.985 ± 1.773 mg kg -1 ) and liver tissue of L. griseus (58.248 ± 8.736 mg kg -1 ). Meanwhile, L. calcarifer has the lowest concentration of Cd in both muscle (0.007 ± 0.004 mg kg -1 ) and liver tissue (0.027 ± 0.016 mg kg -1 ). The heavy metal concentration in muscle tissue is below the permissible limit guidelines stipulated by the Food & Agriculture Organization, 1983 and Malaysia Food Act, 1983. The concentration of heavy metals varies significantly among fish species and tissues. L. campechanus was found to have a higher ability to accumulate heavy metals as compared to the other two species (p heavy metals compared to muscle tissue (p heavy metal concentration in mariculture fish must be performed to prevent acute and chronic food intoxication. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Extrasolar planets: constraints for planet formation models.

    Science.gov (United States)

    Santos, Nuno C; Benz, Willy; Mayor, Michel

    2005-10-14

    Since 1995, more than 150 extrasolar planets have been discovered, most of them in orbits quite different from those of the giant planets in our own solar system. The number of discovered extrasolar planets demonstrates that planetary systems are common but also that they may possess a large variety of properties. As the number of detections grows, statistical studies of the properties of exoplanets and their host stars can be conducted to unravel some of the key physical and chemical processes leading to the formation of planetary systems.

  3. Characterization of Extrasolar Planets Using SOFIA

    Science.gov (United States)

    Deming, Drake

    2010-01-01

    Topics include: the landscape of extrasolar planets, why focus on transiting planets, some history and Spitzer results, problems in atmospheric structure or hot Jupiters and hot super Earths, what observations are needed to make progress, and what SOFIA can currently do and comments on optimized instruments.

  4. Polarization Spectra of Extrasolar Giant Planets

    NARCIS (Netherlands)

    Stam, D.M.

    2004-01-01

    We present simulated spectra of the flux and degree of polarization of starlight that is reflected by extrasolar giant planets (EGPs). In particular the polarization depends strongly on the structure of the planetary atmosphere, and appears to be a valuable tool for the characterization of EGPs.

  5. Extrasolar planets searches today and tomorrow

    CERN Multimedia

    2000-01-01

    So far the searches for extrasolar planets have found 40 planetary companions orbiting around nearby stars. In December 1999 a transit has been observed for one of them, providing the first independent confirmation of the reality of close-in planets as well as a measurement of its density. The techniques used to detect planets are limited and the detection threshold is biased but a first picture of the planet diversity and distribution emerges. Results of the search for extra-solar planets and their impacts on planetary formation will be reviewed. Future instruments are foreseen to detect Earth-like planets and possible signatures of organic activity. An overview of these future projects will be presented and more particularly the Darwin-IRSI mission studied by ESA for Horizon 2015.

  6. The ExtraSolar Planetary Imaging Coronagraph

    Science.gov (United States)

    Clampin, M.; Lyon, R.

    2010-10-01

    The Extrasolar Planetary Imaging Coronagraph (EPIC) is a 1.65-m telescope employing a visible nulling coronagraph (VNC) to deliver high-contrast images of extrasolar system architectures. EPIC will survey the architectures of exosolar systems, and investigate the physical nature of planets in these solar systems. EPIC will employ a Visible Nulling Coronagraph (VNC), featuring an inner working angle of ≤2λ/D, and offers the ideal balance between performance and feasibility of implementation, while not sacrificing science return. The VNC does not demand unrealistic thermal stability from its telescope optics, achieving its primary mirror surface figure requires no new technology, and pointing stability is within state of the art. The EPIC mission will be launched into a drift-away orbit with a five-year mission lifetime.

  7. [Extrasolar terrestrial planets and possibility of extraterrestrial life].

    Science.gov (United States)

    Ida, Shigeru

    2003-12-01

    Recent development of research on extrasolar planets are reviewed. About 120 extrasolar Jupiter-mass planets have been discovered through the observation of Doppler shift in the light of their host stars that is caused by acceleration due to planet orbital motions. Although the extrasolar planets so far observed may be limited to gas giant planets and their orbits differ from those of giant planets in our Solar system (Jupiter and Saturn), the theoretically predicted probability of existence of extrasolar terrestrial planets that can have liquid water ocean on their surface is comparable to that of detectable gas giant planets. Based on the number of extrasolar gas giants detected so far, about 100 life-sustainable planets may exist within a range of 200 light years. Indirect observation of extrasolar terrestrial planets would be done with space telescopes within several years and direct one may be done within 20 years. The latter can detect biomarkers on these planets as well.

  8. Formation, habitability, and detection of extrasolar moons.

    Science.gov (United States)

    Heller, René; Williams, Darren; Kipping, David; Limbach, Mary Anne; Turner, Edwin; Greenberg, Richard; Sasaki, Takanori; Bolmont, Emeline; Grasset, Olivier; Lewis, Karen; Barnes, Rory; Zuluaga, Jorge I

    2014-09-01

    The diversity and quantity of moons in the Solar System suggest a manifold population of natural satellites exist around extrasolar planets. Of peculiar interest from an astrobiological perspective, the number of sizable moons in the stellar habitable zones may outnumber planets in these circumstellar regions. With technological and theoretical methods now allowing for the detection of sub-Earth-sized extrasolar planets, the first detection of an extrasolar moon appears feasible. In this review, we summarize formation channels of massive exomoons that are potentially detectable with current or near-future instruments. We discuss the orbital effects that govern exomoon evolution, we present a framework to characterize an exomoon's stellar plus planetary illumination as well as its tidal heating, and we address the techniques that have been proposed to search for exomoons. Most notably, we show that natural satellites in the range of 0.1-0.5 Earth mass (i) are potentially habitable, (ii) can form within the circumplanetary debris and gas disk or via capture from a binary, and (iii) are detectable with current technology.

  9. Elemental compositions of two extrasolar rocky planetesimals

    Energy Technology Data Exchange (ETDEWEB)

    Xu, S.; Jura, M.; Klein, B.; Zuckerman, B. [Department of Physics and Astronomy, University of California, Los Angeles, CA 90095-1562 (United States); Koester, D., E-mail: sxu@astro.ucla.edu, E-mail: jura@astro.ucla.edu, E-mail: kleinb@astro.ucla.edu, E-mail: ben@astro.ucla.edu, E-mail: koester@astrophysik.uni-kiel.de [Institut fur Theoretische Physik und Astrophysik, University of Kiel, D-24098 Kiel (Germany)

    2014-03-10

    We report Keck/HIRES and Hubble Space Telescope/COS spectroscopic studies of extrasolar rocky planetesimals accreted onto two hydrogen atmosphere white dwarfs, G29-38 and GD 133. In G29-38, eight elements are detected, including C, O, Mg, Si, Ca, Ti, Cr, and Fe while in GD 133, O, Si, Ca, and marginally Mg are seen. These two extrasolar planetesimals show a pattern of refractory enhancement and volatile depletion. For G29-38, the observed composition can be best interpreted as a blend of a chondritic object with some refractory-rich material, a result from post-nebular processing. Water is very depleted in the parent body accreted onto G29-38, based on the derived oxygen abundance. The inferred total mass accretion rate in GD 133 is the lowest of all known dusty white dwarfs, possibly due to non-steady state accretion. We continue to find that a variety of extrasolar planetesimals all resemble to zeroth order the elemental composition of bulk Earth.

  10. Identifying Risk Factors for Late-Onset (50+) Alcohol Use Disorder and Heavy Drinking

    DEFF Research Database (Denmark)

    Emiliussen, Jakob; Nielsen, Anette Søgaard; Andersen, Kjeld

    2017-01-01

    databases: MEDLINE, EMBASE, PubMed, and PsychInfo. Nine studies were included in the final review. Results: The search revealed that only very few studies have been conducted. Hence, the evidence is limited but suggests that stress, role/identity loss, and friends’approval of drinking are associated...... base their conclusions on a certain preconception of older adults with alcohol problems, which leads to a rowof circular arguments. The factors that have been measured seem to have changed over time. Conclusion: There has been a lack of focus on the field of late-onset AUD since the 1970s, which...

  11. Infrared radiation from an extrasolar planet

    OpenAIRE

    Deming, Drake; Seager, Sara; Richardson, L. Jeremy; Harrington, Joseph

    2005-01-01

    A class of extrasolar giant planets - the so-called `hot Jupiters' - orbit within 0.05 AU of their primary stars. These planets should be hot and so emit detectable infrared radiation. The planet HD 209458b is an ideal candidate for the detection and characterization of this infrared light because it is eclipsed by the star. This planet has an anomalously large radius (1.35 times that of Jupiter), which may be the result of ongoing tidal dissipation, but this explanation requires a non-zero o...

  12. Reflected Light Curves of Extrasolar Planets

    Science.gov (United States)

    Green, D.; Matthews, J.; Kuschnig, R.; Seager, S.

    The planned launches of ultra-precise photometric satellites such as MOST, COROT and MONS should provide the first opportunity to study the reflected light curves from extrasolar planets. To predict the capabilities of these missions, we have constructed a series of models of such light curves, improving upon the Monte Carlo simulations by Seager et al. (2000). These models include more realistic features such limb darkening of the star and broad band photometry. For specific models, the resulting planet light curves exhibit unique behavior with the variation of radius, inclination and presence or absence of clouds.

  13. Atmospheric dynamics of tidally synchronized extrasolar planets.

    Science.gov (United States)

    Cho, James Y-K

    2008-12-13

    Tidally synchronized planets present a new opportunity for enriching our understanding of atmospheric dynamics on planets. Subject to an unusual forcing arrangement (steady irradiation on the same side of the planet throughout its orbit), the dynamics on these planets may be unlike that on any of the Solar System planets. Characterizing the flow pattern and temperature distribution on the extrasolar planets is necessary for reliable interpretation of data currently being collected, as well as for guiding future observations. In this paper, several fundamental concepts from atmospheric dynamics, likely to be central for characterization, are discussed. Theoretical issues that need to be addressed in the near future are also highlighted.

  14. Extrasolar planets formation, detection and dynamics

    CERN Document Server

    Dvorak, Rudolf

    2008-01-01

    This latest, up-to-date resource for research on extrasolar planets covers formation, dynamics, atmospheres and detection. After a look at the formation of giant planets, the book goes on to discuss the formation and dynamics of planets in resonances, planets in double stars, atmospheres and habitable zones, detection via spectra and transits, and the history and prospects of ESPs as well as satellite projects.Edited by a renowned expert in solar system dynamics with chapters written by the leading experts in the method described -- from the US and Europe -- this is an ideal textbook for g

  15. Homes for extraterrestrial life: extrasolar planets.

    Science.gov (United States)

    Latham, D W

    2001-12-01

    Astronomers are now discovering giant planets orbiting other stars like the sun by the dozens. But none of these appears to be a small rocky planet like the earth, and thus these planets are unlikely to be capable of supporting life as we know it. The recent discovery of a system of three planets is especially significant because it supports the speculation that planetary systems, as opposed to single orbiting planets, may be common. Our ability to detect extrasolar planets will continue to improve, and space missions now in development should be able to detect earth-like planets.

  16. Photometric Detection of Extra-Solar Planets

    Science.gov (United States)

    Hatzes, Artie P.; Cochran, William D.

    2004-01-01

    This NASA Origins Program grant supported the TEMPEST Texas McDonald Photometric Extrasolar Search for Transits) program at McDonald Observatory, which searches for transits of extrasolar planets across the disks of their parent stars. The basic approach is to use a wide-field ground-based telescope (in our case the McDonald Observatory 0.76m telescope and it s Prime Focus Corrector) to search for transits of short period (1-15 day orbits) of close-in hot-Jupiter planets in orbit around a large sample of field stars. The next task is to search these data streams for possible transit events. We collected our first set of test data for this program using the 0.76 m PFC in the summer of 1998. From those data, we developed the optimal observing procedures, including tailoring the stellar density, exposure times, and filters to best-suit the instrument and project. In the summer of 1999, we obtained the first partial season of data on a dedicated field in the constellation Cygnus. These data were used to develop and refine the reduction and analysis procedures to produce high-precision photometry and search for transits in the resulting light curves. The TeMPEST project subsequently obtained three full seasons of data on six different fields using the McDonald Observatory 0.76m PFC.

  17. IONIZATION OF EXTRASOLAR GIANT PLANET ATMOSPHERES

    International Nuclear Information System (INIS)

    Koskinen, Tommi T.; Cho, James Y-K.; Achilleos, Nicholas; Aylward, Alan D.

    2010-01-01

    Many extrasolar planets orbit close in and are subject to intense ionizing radiation from their host stars. Therefore, we expect them to have strong, and extended, ionospheres. Ionospheres are important because they modulate escape in the upper atmosphere and can modify circulation, as well as leave their signatures, in the lower atmosphere. In this paper, we evaluate the vertical location Z I and extent D I of the EUV ionization peak layer. We find that Z I ∼1-10 nbar-for a wide range of orbital distances (a = 0.047-1 AU) from the host star-and D I /H p ∼>15, where H p is the pressure scale height. At Z I , the plasma frequency is ∼80-450 MHz, depending on a. We also study global ion transport, and its dependence on a, using a three-dimensional thermosphere-ionosphere model. On tidally synchronized planets with weak intrinsic magnetic fields, our model shows only a small, but discernible, difference in electron density from the dayside to the nightside (∼9 x 10 13 m -3 to ∼2 x 10 12 m -3 , respectively) at Z I . On asynchronous planets, the distribution is essentially uniform. These results have consequences for hydrodynamic modeling of the atmospheres of close-in extrasolar giant planets.

  18. Gravitational waves emitted by extrasolar planetary systems

    International Nuclear Information System (INIS)

    Berti, E.; Ferrari, V.

    2001-01-01

    The recently discovered Extrasolar Planetary Systems (EPS's) are potentially interesting sources of gravitational waves, since they are very close to Earth (at distances ∼ 10 pc), and their orbital features and positions in the sky are quite well known. As a first estimate, we compute the orbital emission of these systems using the quadrupole formula. Then we show that, in principle, the orbiting planet could resonantly excite the quasi-normal modes of the central star. We use the general-relativistic theory of stellar pulsations to estimate the effects of such a resonance on the gravitational-wave emission of the system. We also consider radiation-reaction effects on the orbital evolution, and give upper limits on the timescales required for a planet to get off-resonance. (author)

  19. Extrasolar planets and their host stars

    CERN Document Server

    von Braun, Kaspar

    2017-01-01

    This book explores the relations between physical parameters of extrasolar planets and their respective parent stars. Planetary parameters are often directly dependent upon their stellar counterparts. In addition, the star is almost always the only visible component of the system and contains most of the system mass. Consequently, the parent star heavily influences every aspect of planetary physics and astrophysics. Drs. Kaspar von Braun and Tabetha Boyajian use direct methods to characterize exoplanet host starts that minimize the number of assumptions needed to be made in the process. The book provides a background on interferometric techniques for stellar diameter measurements, illustrates the authors' approach on using additional data to fully characterize the stars, provides a comprehensive update on the current state of the field, and examines in detail a number of historically significant and well-studied exoplanetary systems.

  20. The Detection and Characterization of Extrasolar Planets

    Directory of Open Access Journals (Sweden)

    Ken Rice

    2014-09-01

    Full Text Available We have now confirmed the existence of > 1800 planets orbiting stars other thanthe Sun; known as extrasolar planets or exoplanets. The different methods for detectingsuch planets are sensitive to different regions of parameter space, and so, we are discoveringa wide diversity of exoplanets and exoplanetary systems. Characterizing such planets isdifficult, but we are starting to be able to determine something of their internal compositionand are beginning to be able to probe their atmospheres, the first step towards the detectionof bio-signatures and, hence, determining if a planet could be habitable or not. Here, Iwill review how we detect exoplanets, how we characterize exoplanetary systems and theexoplanets themselves, where we stand with respect to potentially habitable planets and howwe are progressing towards being able to actually determine if a planet could host life or not.

  1. Optimized Strategies for Detecting Extrasolar Space Weather

    Science.gov (United States)

    Hallinan, Gregg

    2018-06-01

    Fully understanding the implications of space weather for the young solar system, as well as the wider population of planet-hosting stars, requires remote sensing of space weather in other stellar systems. Solar coronal mass ejections can be accompanied by bright radio bursts at low frequencies (typically measurement of the magnetic field strength of the planet, informing on whether the atmosphere of the planet can survive the intense magnetic activity of its host star. However, both stellar and planetary radio emission are highly variable and optimal strategies for detection of these emissions requires the capability to monitor 1000s of nearby stellar/planetary systems simultaneously. I will discuss optimized strategies for both ground and space-based experiments to take advantage of the highly variable nature of the radio emissions powered by extrasolar space weather to enable detection of stellar CMEs and planetary magnetospheres.

  2. Spitzer Evidence for a Late Heavy Bombardment and the Formation of Urelites in {eta}Corvi at Approximately 1 Gyr

    Science.gov (United States)

    Lisse, C. M.; Wyatt, M. C.; Chen, C. H.; Morlok, A.; Watson, D. M.; Manj, P.; Sheehan, P.; Currie, T. M.; Thebault, P.; Sitko, M. L.

    2011-01-01

    We have analyzed Spitzer and NASA/IRTF 2 - 35 micrometer spectra of the warm, 350 K circumstellar dust around the nearby MS star eta Corvi (F2V, 1.4 plus or minus 0.3 Gyr). The spectra show clear evidence for warm, water- and carbon-rich dust at 3 AU from the central star, in the system's Terrestrial Habitability Zone. Spectral features due to ultra-primitive cometary material were found, in addition to features due to impact produced silica and high temperature carbonaceous phases. At least 9 x 10(exp 18) kg of 0.1 - 100 micrometer warm dust is present in a collisional equilibrium distribution with dn/da a(exp -3.5), the equivalent of a 130 km radius KBO of 1.0 grams per cubic centimeter density and similar to recent estimates of the mass delivered to the Earth at 0.6 - 0.8 Gyr during the Late Heavy Bombardment. We conclude that the parent body was a Kuiper-Belt body or bodies which captured a large amount of early primitive material in the first Myrs of the system's lifetime and preserved it in deep freeze at approximately 150 AU. At approximately 1.4 Gyr they were prompted by dynamical stirring of their parent Kuiper Belt into spiraling into the inner system, eventually colliding at 5-10 kilometers per second with a rocky planetary body of mass less than or equal to M(sub Earth at approximately 3 AU, delivering large amounts of water (greater than 0.1 % of M(sub Earth's Oceans)) and carbon-rich material. The Spitzer spectrum also closely matches spectra reported for the Ureilite meteorites of the Sudan Almahata Sitta fall in 2008, suggesting that one of the Ureilite parent bodies was a KBO.

  3. SPITZER EVIDENCE FOR A LATE-HEAVY BOMBARDMENT AND THE FORMATION OF UREILITES IN {eta} CORVI At {approx}1 Gyr

    Energy Technology Data Exchange (ETDEWEB)

    Lisse, C. M. [JHU-APL, 11100 Johns Hopkins Road, Laurel, MD 20723 (United States); Wyatt, M. C. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge, CB3 0HA (United Kingdom); Chen, C. H. [STScI, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Morlok, A. [Department of Earth and Planetary Sciences, The Open University, Milton-Keynes (United Kingdom); Watson, D. M.; Manoj, P.; Sheehan, P. [Department of Physics and Astronomy, University of Rochester, Rochester, NY (United States); Currie, T. M. [NASA-GSFC, Code 667, Greenbelt, MD 20771 (United States); Thebault, P. [Observatoire de Paris, F-92195 Meudon Principal Cedex (France); Sitko, M. L., E-mail: carey.lisse@jhuapl.edu, E-mail: wyatt@ast.cam.ac.uk, E-mail: cchen@stsci.edu, E-mail: a.morlok@open.ac.uk, E-mail: dmw@pas.rochester.edu, E-mail: manoj@pas.rochester.edu, E-mail: psheeha2@mail.rochester.edu, E-mail: thayne.m.currie@nasa.gov, E-mail: philippe.thebault@obspm.fr, E-mail: sitko@spacescience.org [Space Science Institute, 475 Walnut Street, Suite 205, Boulder, CO 80301 (United States)

    2012-03-10

    We have analyzed Spitzer and NASA/IRTF 2-35 {mu}m spectra of the warm, {approx}350 K circumstellar dust around the nearby MS star {eta} Corvi (F2V, 1.4 {+-} 0.3 Gyr). The spectra show clear evidence for warm, water- and carbon-rich dust at {approx}3 AU from the central star, in the system's terrestrial habitability zone. Spectral features due to ultra-primitive cometary material were found, in addition to features due to impact produced silica and high-temperature carbonaceous phases. At least 9 Multiplication-Sign 10{sup 18} kg of 0.1-100 {mu}m warm dust is present in a collisional equilibrium distribution with dn/da {approx} a{sup -3.5}, the equivalent of a 130 km radius Kuiper Belt object (KBO) of 1.0 g cm{sup 3} density and similar to recent estimates of the mass delivered to the Earth at 0.6-0.8 Gyr during the late-heavy bombardment. We conclude that the parent body was a Kuiper Belt body or bodies which captured a large amount of early primitive material in the first megayears of the system's lifetime and preserved it in deep freeze at {approx}150 AU. At {approx}1.4 Gyr they were prompted by dynamical stirring of their parent Kuiper Belt into spiraling into the inner system, eventually colliding at 5-10 km s{sup -1} with a rocky planetary body of mass {<=}M{sub Earth} at {approx}3 AU, delivering large amounts of water (>0.1% of M{sub Earth'sOceans}) and carbon-rich material. The Spitzer spectrum also closely matches spectra reported for the Ureilite meteorites of the Sudan Almahata Sitta fall in 2008, suggesting that one of the Ureilite parent bodies was a KBO.

  4. SPITZER EVIDENCE FOR A LATE-HEAVY BOMBARDMENT AND THE FORMATION OF UREILITES IN η CORVI At ∼1 Gyr

    International Nuclear Information System (INIS)

    Lisse, C. M.; Wyatt, M. C.; Chen, C. H.; Morlok, A.; Watson, D. M.; Manoj, P.; Sheehan, P.; Currie, T. M.; Thebault, P.; Sitko, M. L.

    2012-01-01

    We have analyzed Spitzer and NASA/IRTF 2-35 μm spectra of the warm, ∼350 K circumstellar dust around the nearby MS star η Corvi (F2V, 1.4 ± 0.3 Gyr). The spectra show clear evidence for warm, water- and carbon-rich dust at ∼3 AU from the central star, in the system's terrestrial habitability zone. Spectral features due to ultra-primitive cometary material were found, in addition to features due to impact produced silica and high-temperature carbonaceous phases. At least 9 × 10 18 kg of 0.1-100 μm warm dust is present in a collisional equilibrium distribution with dn/da ∼ a –3.5 , the equivalent of a 130 km radius Kuiper Belt object (KBO) of 1.0 g cm 3 density and similar to recent estimates of the mass delivered to the Earth at 0.6-0.8 Gyr during the late-heavy bombardment. We conclude that the parent body was a Kuiper Belt body or bodies which captured a large amount of early primitive material in the first megayears of the system's lifetime and preserved it in deep freeze at ∼150 AU. At ∼1.4 Gyr they were prompted by dynamical stirring of their parent Kuiper Belt into spiraling into the inner system, eventually colliding at 5-10 km s –1 with a rocky planetary body of mass ≤M Earth at ∼3 AU, delivering large amounts of water (>0.1% of M Earth'sOceans ) and carbon-rich material. The Spitzer spectrum also closely matches spectra reported for the Ureilite meteorites of the Sudan Almahata Sitta fall in 2008, suggesting that one of the Ureilite parent bodies was a KBO.

  5. Extrasolar Planets Swiss Society for Astrophysics and Astronomy

    CERN Document Server

    Cassen, Patrick; Quirrenbach, Andreas

    2006-01-01

    Research on extrasolar planets is one of the most exciting fields of activity in astrophysics. In a decade only, a huge step forward has been made from the early speculations on the existence of planets orbiting "other stars" to the first discoveries and to the characterization of extrasolar planets. This breakthrough is the result of a growing interest of a large community of researchers as well as the development of a wide range of new observational techniques and facilities. Based on their lectures given at the 31st Saas-Fee Advanced Course, Andreas Quirrenbach, Tristan Guillot and Pat Cassen have written up up-to-date comprehensive lecture notes on the "Detection and Characterization of Extrasolar Planets", "Physics of Substellar Objects Interiors, Atmospheres, Evolution" and "Protostellar Disks and Planet Formation". This book will serve graduate students, lecturers and scientists entering the field of extrasolar planets as detailed and comprehensive introduction.

  6. Possibilities for the detection of microbial life on extrasolar planets.

    Science.gov (United States)

    Knacke, Roger F

    2003-01-01

    We consider possibilities for the remote detection of microbial life on extrasolar planets. The Darwin/Terrestrial Planet Finder (TPF) telescope concepts for observations of terrestrial planets focus on indirect searches for life through the detection of atmospheric gases related to life processes. Direct detection of extraterrestrial life may also be possible through well-designed searches for microbial life forms. Satellites in Earth orbit routinely monitor colonies of terrestrial algae in oceans and lakes by analysis of reflected ocean light in the visible region of the spectrum. These remote sensing techniques suggest strategies for extrasolar searches for signatures of chlorophylls and related photosynthetic compounds associated with life. However, identification of such life-related compounds on extrasolar planets would require observations through strong, interfering absorptions and scattering radiances from the remote atmospheres and landmasses. Techniques for removal of interfering radiances have been extensively developed for remote sensing from Earth orbit. Comparable techniques would have to be developed for extrasolar planet observations also, but doing so would be challenging for a remote planet. Darwin/TPF coronagraph concepts operating in the visible seem to be best suited for searches for extrasolar microbial life forms with instruments that can be projected for the 2010-2020 decades, although resolution and signal-to-noise ratio constraints severely limit detection possibilities on terrestrial-type planets. The generation of telescopes with large apertures and extremely high spatial resolutions that will follow Darwin/TPF could offer striking possibilities for the direct detection of extrasolar microbial life.

  7. Infrared radiation from an extrasolar planet.

    Science.gov (United States)

    Deming, Drake; Seager, Sara; Richardson, L Jeremy; Harrington, Joseph

    2005-04-07

    A class of extrasolar giant planets--the so-called 'hot Jupiters' (ref. 1)--orbit within 0.05 au of their primary stars (1 au is the Sun-Earth distance). These planets should be hot and so emit detectable infrared radiation. The planet HD 209458b (refs 3, 4) is an ideal candidate for the detection and characterization of this infrared light because it is eclipsed by the star. This planet has an anomalously large radius (1.35 times that of Jupiter), which may be the result of ongoing tidal dissipation, but this explanation requires a non-zero orbital eccentricity (approximately 0.03; refs 6, 7), maintained by interaction with a hypothetical second planet. Here we report detection of infrared (24 microm) radiation from HD 209458b, by observing the decrement in flux during secondary eclipse, when the planet passes behind the star. The planet's 24-microm flux is 55 +/- 10 microJy (1sigma), with a brightness temperature of 1,130 +/- 150 K, confirming the predicted heating by stellar irradiation. The secondary eclipse occurs at the midpoint between transits of the planet in front of the star (to within +/- 7 min, 1sigma), which means that a dynamically significant orbital eccentricity is unlikely.

  8. Photometric Defocus Observations of Transiting Extrasolar Planets

    Directory of Open Access Journals (Sweden)

    Tobias C. Hinse

    2015-03-01

    Full Text Available We have carried out photometric follow-up observations of bright transiting extrasolar planets using the CbNUOJ 0.6 m telescope. We have tested the possibility of obtaining high photometric precision by applying the telescope defocus technique, allowing the use of several hundred seconds in exposure time for a single measurement. We demonstrate that this technique is capable of obtaining a root-mean-square scatter of sub-millimagnitude order over several hours for a V ~10 host star, typical for transiting planets detected from ground-based survey facilities. We compared our results with transit observations from a telescope operated in in-focus mode. High photometric precision was obtained due to the collection of a larger amount of photons, resulting in a higher signal compared to other random and systematic noise sources. Accurate telescope tracking is likely to further contribute to lowering systematic noise by exposing the same pixels on the CCD. Furthermore, a longer exposure time helps reduce the effect of scintillation noise which otherwise has a significant effect for small-aperture telescopes operated in in-focus mode. Finally we present the results of modelling four light-curves in which a root-mean-square scatter of 0.70 to 2.3 milli-magnitudes was achieved.

  9. From Extrasolar Planets to Exo-Earths

    Science.gov (United States)

    Fischer, Debra

    2018-06-01

    The ancient Greeks debated whether the Earth was unique, or innumerable worlds existed around other Suns. Twenty five years ago, technology and human ingenuity enabled the discovery of the first extrasolar planet candidates. The architectures of these first systems, with gas giant planets in star-skirting orbits, were unexpected and again raised an echo of that ancient question: is the Earth typical or unique? We are interested in this seemingly anthropocentric question because with all of our searching and discoveries, Earth is the only place where life has been found. It is the question of whether life exists elsewhere that energizes the search for exoplanets. The trajectory of this field has been stunning. After a steady stream of detections with the radial velocity method, a burst of discovery was made possible with the NASA Kepler mission. While thousands of smaller planets have now been found, true Earth analogs have eluded robust detection. However, we are sharpening the knives of our technology and without a doubt we now stand at the threshold of detecting hundreds of Earth analogs. Using Gaia, TESS, WFIRST, JWST and new ground-based spectrographs, we will learn the names and addresses of the worlds that orbit nearby stars and we will be ready to probe their atmospheres. We will finally resolve the ancient question of whether life is unique or common.

  10. Direct Imaging of Warm Extrasolar Planets

    International Nuclear Information System (INIS)

    Macintosh, B

    2005-01-01

    One of the most exciting scientific discoveries in the last decade of the twentieth century was the first detection of planets orbiting a star other than our own. By now more than 130 extrasolar planets have been discovered indirectly, by observing the gravitational effects of the planet on the radial velocity of its parent star. This technique has fundamental limitations: it is most sensitive to planets close to their star, and it determines only a planet's orbital period and a lower limit on the planet's mass. As a result, all the planetary systems found so far are very different from our own--they have giant Jupiter-sized planets orbiting close to their star, where the terrestrial planets are found in our solar system. Such systems have overturned the conventional paradigm of planet formation, but have no room in them for habitable Earth-like planets. A powerful complement to radial velocity detections of extrasolar planets will be direct imaging--seeing photons from the planet itself. Such a detection would allow photometric measurements to determine the temperature and radius of a planet. Also, direct detection is most sensitive to planets in wide orbits, and hence more capable of seeing solar systems resembling our own, since a giant planet in a wide orbit does not preclude the presence of an Earth-like planet closer to the star. Direct detection, however, is extremely challenging. Jupiter is roughly a billion times fainter than our sun. Two techniques allowed us to overcome this formidable contrast and attempt to see giant planets directly. The first is adaptive optics (AO) which allows giant earth-based telescopes, such as the 10 meter W.M. Keck telescope, to partially overcome the blurring effects of atmospheric turbulence. The second is looking for young planets: by searching in the infrared for companions to young stars, we can see thermal emission from planets that are still warm with the heat of their formation. Together with a UCLA team that leads the

  11. High-Cadence Transit Timing Variation Monitoring of Extrasolar Planets

    Directory of Open Access Journals (Sweden)

    Naef D.

    2011-02-01

    Full Text Available We report ground-based high-cadence transit timing observations of the extrasolar planet WASP-2b. We achieve a typical timing error of 15-30 sec. The data show no significant deviations from the predicted ephemeris.

  12. Direct Imaging Search for Extrasolar Planets in the Pleiades

    NARCIS (Netherlands)

    Yamamoto, K.; et al., [Unknown; Thalmann, C.

    2013-01-01

    We carried out an imaging survey for extrasolar planets around stars in the Pleiades (125 Myr, 135 pc) in the H and KS bands using HiCIAO combined with adaptive optics, AO188, on the Subaru telescope. We found 13 companion candidates fainter than 14.5 mag in the H band around 9 stars. Five of these

  13. Stratigraphy, Sequence, and Crater Populations of Lunar Impact Basins from Lunar Orbiter Laser Altimeter (LOLA) Data: Implications for the Late Heavy Bombardment

    Science.gov (United States)

    Fassett, C. I.; Head, J. W.; Kadish, S. J.; Mazarico, E.; Neumann, G. A.; Smith, D. E.; Zuber, M. T.

    2012-01-01

    New measurements of the topography of the Moon from the Lunar Orbiter Laser Altimeter (LOLA)[1] provide an excellent base-map for analyzing the large crater population (D.20 km)of the lunar surface [2, 3]. We have recently used this data to calculate crater size-frequency distributions (CSFD) for 30 lunar impact basins, which have implications for their stratigraphy and sequence. These data provide an avenue for assessing the timing of the transitions between distinct crater populations characteristic of ancient and young lunar terrains, which has been linked to the late heavy bombardment (LHB). We also use LOLA data to re-examine relative stratigraphic relationships between key lunar basins.

  14. Orbital parameters of extrasolar planets derived from polarimetry

    Science.gov (United States)

    Fluri, D. M.; Berdyugina, S. V.

    2010-03-01

    Context. Polarimetry of extrasolar planets becomes a new tool for their investigation, which requires the development of diagnostic techniques and parameter case studies. Aims: Our goal is to develop a theoretical model which can be applied to interpret polarimetric observations of extrasolar planets. Here we present a theoretical parameter study that shows the influence of the various involved parameters on the polarization curves. Furthermore, we investigate the robustness of the fitting procedure. We focus on the diagnostics of orbital parameters and the estimation of the scattering radius of the planet. Methods: We employ the physics of Rayleigh scattering to obtain polarization curves of an unresolved extrasolar planet. Calculations are made for two cases: (i) assuming an angular distribution for the intensity of the scattered light as from a Lambert sphere and for polarization as from a Rayleigh-type scatterer; and (ii) assuming that both the intensity and polarization of the scattered light are distributed according to the Rayleigh law. We show that the difference between these two cases is negligible for the shapes of the polarization curves. In addition, we take the size of the host star into account, which is relevant for hot Jupiters orbiting giant stars. Results: We discuss the influence of the inclination of the planetary orbit, the position angle of the ascending node, and the eccentricity on the linearly polarized light curves both in Stokes Q/I and U/I. We also analyze errors that arise from the assumption of a point-like star in numerical modeling of polarization as compared to consistent calculations accounting for the finite size of the host star. We find that errors due to the point-like star approximation are reduced with the size of the orbit, but still amount to about 5% for known hot Jupiters. Recovering orbital parameters from simulated data is shown to be very robust even for very noisy data because the polarization curves react

  15. ENHANCED INTERFEROMETRIC IDENTIFICATION OF SPECTRA IN HABITABLE EXTRASOLAR PLANETS

    International Nuclear Information System (INIS)

    Schwartz, Eyal; Lipson, Stephen G.; Ribak, Erez N.

    2012-01-01

    An Earth-like extrasolar planet emits light that is many orders of magnitude fainter than that of the parent star. We propose a method of identifying bio-signature spectral lines in light of known extrasolar planets based on Fourier spectroscopy in the infrared, using an off-center part of a Fourier interferogram only. This results in superior sensitivity to narrower molecular-type spectral bands, which are expected in the planet spectrum but are absent in the parent star. We support this idea by numerical simulations that include photon and thermal noise, and show it to be feasible at a luminosity ratio of 10 –6 for a Sun-like parent star in the infrared. We also carried out a laboratory experiment to illustrate the method. The results suggest that this method should be applicable to real planet searches.

  16. Pervasive orbital eccentricities dictate the habitability of extrasolar earths.

    Science.gov (United States)

    Kita, Ryosuke; Rasio, Frederic; Takeda, Genya

    2010-09-01

    The long-term habitability of Earth-like planets requires low orbital eccentricities. A secular perturbation from a distant stellar companion is a very important mechanism in exciting planetary eccentricities, as many of the extrasolar planetary systems are associated with stellar companions. Although the orbital evolution of an Earth-like planet in a stellar binary system is well understood, the effect of a binary perturbation on a more realistic system containing additional gas-giant planets has been very little studied. Here, we provide analytic criteria confirmed by a large ensemble of numerical integrations that identify the initial orbital parameters leading to eccentric orbits. We show that an extrasolar earth is likely to experience a broad range of orbital evolution dictated by the location of a gas-giant planet, which necessitates more focused studies on the effect of eccentricity on the potential for life.

  17. Views from EPOXI. Colors in Our Solar System as an Analog for Extrasolar Planets

    Science.gov (United States)

    Crow, Carolyn A.; McFadden, L. A.; Robinson, T.; Livengood, T. A.; Hewagama, T.; Barry, R. K.; Deming, L. D.; Meadows, V.; Lisse, C. M.

    2010-01-01

    With extrasolar planet detection becoming more common place, the frontiers of extrasolar planet science have moved beyond detection to the observations required to determine planetary properties. Once the existing observational challenges have been overcome, the first visible-light studies of extrasolar Earth-sized planets will likely employ filter photometry or low-resolution. spectroscopy to observe disk-integrated radiation from the unresolved planet. While spectroscopy of these targets is highly desirable, and provides the most robust form of characterization. S/N considerations presently limit spectroscopic measurements of extrasolar worlds. Broadband filter photometry will thus serve as a first line of characterization. In this paper we use Extrasolar Observation and Characterization (EPOCh) filter photometry of the Earth. Moon and Mars model spectra. and previous photometric and spectroscopic observations of a range the solar system planets. Titan, and Moon to explore the limitations of using color as a baseline for understanding extrasolar planets

  18. Extrasolar planets as a probe of modified gravity

    OpenAIRE

    Vargas dos Santos, Marcelo; Mota, David F.

    2017-01-01

    We propose a new method to test modified gravity theories, taking advantage of the available data on extrasolar planets. We computed the deviations from the Kepler third law and use that to constrain gravity theories beyond General Relativity. We investigate gravity models which incorporate three screening mechanisms: the Chameleon, the Symmetron and the Vainshtein. We find that data from exoplanets orbits are very sensitive to the screening mechanisms putting strong constraints in the parame...

  19. THE COMPOSITIONAL DIVERSITY OF EXTRASOLAR TERRESTRIAL PLANETS. II. MIGRATION SIMULATIONS

    International Nuclear Information System (INIS)

    Carter-Bond, Jade C.; O'Brien, David P.; Raymond, Sean N.

    2012-01-01

    Prior work has found that a variety of terrestrial planetary compositions are expected to occur within known extrasolar planetary systems. However, such studies ignored the effects of giant planet migration, which is thought to be very common in extrasolar systems. Here we present calculations of the compositions of terrestrial planets that formed in dynamical simulations incorporating varying degrees of giant planet migration. We used chemical equilibrium models of the solid material present in the disks of five known planetary host stars: the Sun, GJ 777, HD4203, HD19994, and HD213240. Giant planet migration has a strong effect on the compositions of simulated terrestrial planets as the migration results in large-scale mixing between terrestrial planet building blocks that condensed at a range of temperatures. This mixing acts to (1) increase the typical abundance of Mg-rich silicates in the terrestrial planets' feeding zones and thus increase the frequency of planets with Earth-like compositions compared with simulations with static giant planet orbits, and (2) drastically increase the efficiency of the delivery of hydrous phases (water and serpentine) to terrestrial planets and thus produce waterworlds and/or wet Earths. Our results demonstrate that although a wide variety of terrestrial planet compositions can still be produced, planets with Earth-like compositions should be common within extrasolar planetary systems.

  20. Magnetic Fields of Extrasolar Planets: Planetary Interiors and Habitability

    Science.gov (United States)

    Lazio, T. Joseph

    2018-06-01

    Ground-based observations showed that Jupiter's radio emission is linked to its planetary-scale magnetic field, and subsequent spacecraft observations have shown that most planets, and some moons, have or had a global magnetic field. Generated by internal dynamos, magnetic fields are one of the few remote sensing means of constraining the properties of planetary interiors. For the Earth, its magnetic field has been speculated to be partially responsible for its habitability, and knowledge of an extrasolar planet's magnetic field may be necessary to assess its habitability. The radio emission from Jupiter and other solar system planets is produced by an electron cyclotron maser, and detections of extrasolar planetary electron cyclotron masers will enable measurements of extrasolar planetary magnetic fields. Based on experience from the solar system, such observations will almost certainly require space-based observations, but they will also be guided by on-going and near-future ground-based observations.This work has benefited from the discussion and participants of the W. M. Keck Institute of Space Studies "Planetary Magnetic Fields: Planetary Interiors and Habitability" and content within a white paper submitted to the National Academy of Science Committee on Exoplanet Science Strategy. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.

  1. First Light from Extrasolar Planets and Implications for Astrobiology

    Science.gov (United States)

    Richardson, L. Jeremy; Seager, Sara; Harrington, Joseph; Deming, Drake

    2005-01-01

    The first light from an extrasolar planet was recently detected. These results, obtained for two transiting extrasolar planets at different infrared wavelengths, open a new era in the field of extrasolar planet detection and characterization because for the first time we can now detect planets beyond the solar system directly. Using the Spitzer Space Telescope at 24 microns, we observed the modulation of combined light (star plus planet) from the HD 209458 system as the planet disappeared behind the star during secondary eclipse and later re-emerged, thereby isolating the light from the planet. We obtained a planet-to-star ratio of 0.26% at 24 microns, corresponding to a brightness temperature of 1130 + / - 150 K. We will describe this result in detail, explain what it can tell us about the atmosphere of HD 209458 b, and discuss implications for the field of astrobiology. These results represent a significant step on the path to detecting terrestrial planets around other stars and in understanding their atmospheres in terms of composition and temperature.

  2. Using polarimetry to detect and characterize Jupiter-like extrasolar planets

    NARCIS (Netherlands)

    Stam, D.M.; Hovenier, J.W.; Waters, L.B.F.M.

    2004-01-01

    Using numerical simulations of flux and polarization spectra of visible to near-infrared starlight reflected by Jupiter-like extrasolar planets, we show that polarimetry can be used both for the detection and for the characterization of extrasolar planets. Polarimetry is valuable for detection

  3. Status of the Calan-Hertfordshire Extrasolar Planet Search

    Directory of Open Access Journals (Sweden)

    Jordán Andres

    2013-04-01

    Full Text Available In these proceedings we give a status update of the Calan-Hertfordshire Extrasolar Planet Search, an international collaboration led from Chile that aims to discover more planets around super metal-rich and Sun-like stars, and then follow these up with precision photometry to hunt for new bright transit planets. We highlight some results from this program, including exoplanet and brown dwarf discoveries, and a possible correlation between metallicity and planetary minimum mass at the lowest planetary masses detectable. Finally we discuss the short-term and long-term future pathways this program can take.

  4. TWO EXTRASOLAR ASTEROIDS WITH LOW VOLATILE-ELEMENT MASS FRACTIONS

    International Nuclear Information System (INIS)

    Jura, M.; Xu, S.; Klein, B.; Zuckerman, B.; Koester, D.

    2012-01-01

    Using ultraviolet spectra obtained with the Cosmic Origins Spectrograph on the Hubble Space Telescope, we extend our previous ground-based optical determinations of the composition of the extrasolar asteroids accreted onto two white dwarfs, GD 40 and G241-6. Combining optical and ultraviolet spectra of these stars with He-dominated atmospheres, 13 and 12 polluting elements are confidently detected in GD 40 and G241-6, respectively. For the material accreted onto GD 40, the volatile elements C and S are deficient by more than a factor of 10 and N by at least a factor of 5 compared to their mass fractions in primitive CI chondrites and approach what is inferred for bulk Earth. A similar pattern is found for G241-6 except that S is undepleted. We have also newly detected or placed meaningful upper limits for the amount of Cl, Al, P, Ni, and Cu in the accreted matter. Extending results from optical studies, the mass fractions of refractory elements in the accreted parent bodies are similar to what is measured for bulk Earth and chondrites. Thermal processing, perhaps interior to a snow line, appears to be of central importance in determining the elemental compositions of these particular extrasolar asteroids.

  5. CALIBRATION OF EQUILIBRIUM TIDE THEORY FOR EXTRASOLAR PLANET SYSTEMS

    International Nuclear Information System (INIS)

    Hansen, Brad M. S.

    2010-01-01

    We provide an 'effective theory' of tidal dissipation in extrasolar planet systems by empirically calibrating a model for the equilibrium tide. The model is valid to high order in eccentricity and parameterized by two constants of bulk dissipation-one for dissipation in the planet and one for dissipation in the host star. We are able to consistently describe the distribution of extrasolar planetary systems in terms of period, eccentricity, and mass (with a lower limit of a Saturn mass) with this simple model. Our model is consistent with the survival of short-period exoplanet systems, but not with the circularization period of equal mass stellar binaries, suggesting that the latter systems experience a higher level of dissipation than exoplanet host stars. Our model is also not consistent with the explanation of inflated planetary radii as resulting from tidal dissipation. The paucity of short-period planets around evolved A stars is explained as the result of enhanced tidal inspiral resulting from the increase in stellar radius with evolution.

  6. THE SURVIVAL OF WATER WITHIN EXTRASOLAR MINOR PLANETS

    International Nuclear Information System (INIS)

    Jura, M.; Xu, S.

    2010-01-01

    We compute that extrasolar minor planets can retain much of their internal H 2 O during their host star's red giant evolution. The eventual accretion of a water-rich body or bodies onto a helium white dwarf might supply an observable amount of atmospheric hydrogen, as seems likely for GD 362. More generally, if hydrogen pollution in helium white dwarfs typically results from accretion of large parent bodies rather than interstellar gas as previously supposed, then H 2 O probably constitutes at least 10% of the aggregate mass of extrasolar minor planets. One observational test of this possibility is to examine the atmospheres of externally polluted white dwarfs for oxygen in excess of that likely contributed by oxides such as SiO 2 . The relatively high oxygen abundance previously reported in GD 378 can be explained plausibly but not uniquely by accretion of an H 2 O-rich parent body or bodies. Future ultraviolet observations of white dwarf pollutions can serve to investigate the hypothesis that environments with liquid water that are suitable habitats for extremophiles are widespread in the Milky Way.

  7. Extrasolar Planetary Imaging Coronagraph (EPIC): visible nulling cornagraph testbed results

    Science.gov (United States)

    Lyon, Richard G.; Clampin, Mark; Melnick, Gary; Tolls, Volker; Woodruff, Robert; Vasudevan, Gopal

    2008-07-01

    The Extrasolar Planetary Imaging Coronagraph (EPIC) is a NASA Astrophysics Strategic Mission Concept under study for the upcoming Exoplanet Probe. EPIC's mission would be to image and characterize extrasolar giant planets, and potential super-Earths, in orbits with semi-major axes between 2 and 10 AU. EPIC will provide insights into the physical nature of a variety of planets in other solar systems complimenting radial velocity (RV) and astrometric planet searches. It will detect and characterize the atmospheres of planets identified by radial velocity surveys and potentially some transits, determine orbital inclinations and masses, characterize the atmospheres of gas giants around A and F stars, observed the inner spatial structure and colors of inner Spitzer selected debris disks. EPIC would be launched into a heliocentric Earth trailing drift-away orbit, with a 3-year mission lifetime (5 year goal) and will revisit planets at least three times. The starlight suppression approach consists of a visible nulling coronagraph (VNC) that enables high order starlight suppression in broadband light. To demonstrate the VNC approach and advance it's technology readiness the NASA/Goddard Space Flight Center and Lockheed-Martin have developed a laboratory VNC and have demonstrated white light nulling. We will discuss our ongoing VNC work and show the latest results from the VNC testbed.

  8. Extrasolar Planetary Imaging Coronagraph: Visible Nulling Coronagraph Testbed Results

    Science.gov (United States)

    Lyon, Richard G.

    2008-01-01

    The Extrasolar Planetary Imaging Coronagraph (EPIC) is a proposed NASA Discovery mission to image and characterize extrasolar giant planets in orbits with semi-major axes between 2 and 10 AU. EPIC will provide insights into the physical nature of a variety of planets in other solar systems complimenting radial velocity (RV) and astrometric planet searches. It will detect and characterize the atmospheres of planets identified by radial velocity surveys, determine orbital inclinations and masses, characterize the atmospheres around A and F stars, observed the inner spatial structure and colors of inner Spitzer selected debris disks. EPIC would be launched to heliocentric Earth trailing drift-away orbit, with a 3-year mission lifetime ( 5 year goal) and will revisit planets at least three times at intervals of 9 months. The starlight suppression approach consists of a visible nulling coronagraph (VNC) that enables high order starlight suppression in broadband light. To demonstrate the VNC approach and advance it's technology readiness the NASA Goddard Space Flight Center and Lockheed-Martin have developed a laboratory VNC and have demonstrated white light nulling. We will discuss our ongoing VNC work and show the latest results from the VNC testbed,

  9. Predicting the Atmospheric Composition of Extrasolar Giant Planets

    Science.gov (United States)

    Sharp, A. G.; Moses, J. I.; Friedson, A. J.; Fegley, B., Jr.; Marley, M. S.; Lodders, K.

    2004-01-01

    To date, approximately 120 planet-sized objects have been discovered around other stars, mostly through the radial-velocity technique. This technique can provide information about a planet s minimum mass and its orbital period and distance; however, few other planetary data can be obtained at this point in time unless we are fortunate enough to find an extrasolar giant planet that transits its parent star (i.e., the orbit is edge-on as seen from Earth). In that situation, many physical properties of the planet and its parent star can be determined, including some compositional information. Our prospects of directly obtaining spectra from extrasolar planets may improve in the near future, through missions like NASA's Terrestrial Planet Finder. Most of the extrasolar giant planets (EGPs) discovered so far have masses equal to or greater than Jupiter's mass, and roughly 16% have orbital radii less than 0.1 AU - extremely close to the parent star by our own Solar-System standards (note that Mercury is located at a mean distance of 0.39 AU and Jupiter at 5.2 AU from the Sun). Although all EGPs are expected to have hydrogen-dominated atmospheres similar to Jupiter, the orbital distance can strongly affect the planet's temperature, physical, chemical, and spectral properties, and the abundance of minor, detectable atmospheric constituents. Thermochemical equilibrium models can provide good zero-order predictions for the atmospheric composition of EGPs. However, both the composition and spectral properties will depend in large part on disequilibrium processes like photochemistry, chemical kinetics, atmospheric transport, and haze formation. We have developed a photochemical kinetics, radiative transfer, and 1-D vertical transport model to study the atmospheric composition of EGPs. The chemical reaction list contains H-, C-, O-, and N-bearing species and is designed to be valid for atmospheric temperatures ranging from 100-3000 K and pressures up to 50 bar. Here we examine

  10. The Problem of Extraterrestrial Civilizations and Extrasolar Planets

    Science.gov (United States)

    Mickaelian, A. M.

    2015-07-01

    The problem of extraterrestrial intelligence is the best example of multidisciplinary science. Here philosophy and religion, astronomy, radiophysics, spectrography, space flights and astronautics, geology and planetology, astroecology, chemistry and biology, history and archaeology, psychology, sociology, linguistics, diplomacy, UFOs and peculiar phenomena are involved. Among these many-sided studies, astronomers have probably displayed the most progress by discovering thousands of extrasolar planets. At present, a number of search programs are being accomplished, including those with space telescopes, and planets in so-called "habitable zone" are considered as most important ones, for which various orbital and physical parameters are being calculated. As the discovery of extraterrestrial life is the final goal, a special attention is given to Earth-like planets, for the discovery of which most sensitive technical means are necessary.

  11. Extrasolar planets as a probe of modified gravity

    Directory of Open Access Journals (Sweden)

    Marcelo Vargas dos Santos

    2017-06-01

    Full Text Available We propose a new method to test modified gravity theories, taking advantage of the available data on extrasolar planets. We computed the deviations from the Kepler third law and use that to constrain gravity theories beyond General Relativity. We investigate gravity models which incorporate three screening mechanisms: the Chameleon, the Symmetron and the Vainshtein. We find that data from exoplanets orbits are very sensitive to the screening mechanisms putting strong constraints in the parameter space for the Chameleon models and the Symmetron, complementary and competitive to other methods, like interferometers and solar system. With the constraints on Vainshtein we are able to work beyond the hypothesis that the crossover scale is of the same order of magnitude than the Hubble radius rc∼H0−1, which makes the screening work automatically, testing how strong this hypothesis is and the viability of other scales.

  12. Extrasolar planets as a probe of modified gravity

    Science.gov (United States)

    Vargas dos Santos, Marcelo; Mota, David F.

    2017-06-01

    We propose a new method to test modified gravity theories, taking advantage of the available data on extrasolar planets. We computed the deviations from the Kepler third law and use that to constrain gravity theories beyond General Relativity. We investigate gravity models which incorporate three screening mechanisms: the Chameleon, the Symmetron and the Vainshtein. We find that data from exoplanets orbits are very sensitive to the screening mechanisms putting strong constraints in the parameter space for the Chameleon models and the Symmetron, complementary and competitive to other methods, like interferometers and solar system. With the constraints on Vainshtein we are able to work beyond the hypothesis that the crossover scale is of the same order of magnitude than the Hubble radius rc ∼ H0-1, which makes the screening work automatically, testing how strong this hypothesis is and the viability of other scales.

  13. Planetary Systems Detection, Formation and Habitability of Extrasolar Planets

    CERN Document Server

    Ollivier, Marc; Casoli, Fabienne; Encrenaz, Thérèse; Selsis, Franck

    2009-01-01

    Over the past ten years, the discovery of extrasolar planets has opened a new field of astronomy, and this area of research is rapidly growing, from both the observational and theoretical point of view. The presence of many giant exoplanets in the close vicinity of their star shows that these newly discovered planetary systems are very different from the solar system. New theoretical models are being developed in order to understand their formation scenarios, and new observational methods are being implemented to increase the sensitivity of exoplanet detections. In the present book, the authors address the question of planetary systems from all aspects. Starting from the facts (the detection of more than 300 extraterrestrial planets), they first describe the various methods used for these discoveries and propose a synthetic analysis of their global properties. They then consider the observations of young stars and circumstellar disks and address the case of the solar system as a specific example, different fr...

  14. Detecting tree-like multicellular life on extrasolar planets.

    Science.gov (United States)

    Doughty, Christopher E; Wolf, Adam

    2010-11-01

    Over the next two decades, NASA and ESA are planning a series of space-based observatories to find Earth-like planets and determine whether life exists on these planets. Previous studies have assessed the likelihood of detecting life through signs of biogenic gases in the atmosphere or a red edge. Biogenic gases and the red edge could be signs of either single-celled or multicellular life. In this study, we propose a technique with which to determine whether tree-like multicellular life exists on extrasolar planets. For multicellular photosynthetic organisms on Earth, competition for light and the need to transport water and nutrients has led to a tree-like body plan characterized by hierarchical branching networks. This design results in a distinct bidirectional reflectance distribution function (BRDF) that causes differing reflectance at different sun/view geometries. BRDF arises from the changing visibility of the shadows cast by objects, and the presence of tree-like structures is clearly distinguishable from flat ground with the same reflectance spectrum. We examined whether the BRDF could detect the existence of tree-like structures on an extrasolar planet by using changes in planetary albedo as a planet orbits its star. We used a semi-empirical BRDF model to simulate vegetation reflectance at different planetary phase angles and both simulated and real cloud cover to calculate disk and rotation-averaged planetary albedo for a vegetated and non-vegetated planet with abundant liquid water. We found that even if the entire planetary albedo were rendered to a single pixel, the rate of increase of albedo as a planet approaches full illumination would be comparatively greater on a vegetated planet than on a non-vegetated planet. Depending on how accurately planetary cloud cover can be resolved and the capabilities of the coronagraph to resolve exoplanets, this technique could theoretically detect tree-like multicellular life on exoplanets in 50 stellar systems.

  15. A Model of the Temporal Variability of Optical Light from Extrasolar Terrestrial Planets

    OpenAIRE

    Ford, Eric B.; Seager, Sara; Turner, Edwin L.

    2002-01-01

    The light scattered by an extrasolar Earth-like planet's surface and atmosphere will vary in intensity and color as the planet rotates; the resulting light curve will contain information about the planet's properties. Since most of the light comes from a small fraction of the planet's surface, the temporal flux variability can be quite significant, $\\sim$ 10-100%. In addition, for cloudless Earth-like extrasolar planet models, qualitative changes to the surface (such as ocean fraction, ice co...

  16. An extrasolar planetary system with three Neptune-mass planets.

    Science.gov (United States)

    Lovis, Christophe; Mayor, Michel; Pepe, Francesco; Alibert, Yann; Benz, Willy; Bouchy, François; Correia, Alexandre C M; Laskar, Jacques; Mordasini, Christoph; Queloz, Didier; Santos, Nuno C; Udry, Stéphane; Bertaux, Jean-Loup; Sivan, Jean-Pierre

    2006-05-18

    Over the past two years, the search for low-mass extrasolar planets has led to the detection of seven so-called 'hot Neptunes' or 'super-Earths' around Sun-like stars. These planets have masses 5-20 times larger than the Earth and are mainly found on close-in orbits with periods of 2-15 days. Here we report a system of three Neptune-mass planets with periods of 8.67, 31.6 and 197 days, orbiting the nearby star HD 69830. This star was already known to show an infrared excess possibly caused by an asteroid belt within 1 au (the Sun-Earth distance). Simulations show that the system is in a dynamically stable configuration. Theoretical calculations favour a mainly rocky composition for both inner planets, while the outer planet probably has a significant gaseous envelope surrounding its rocky/icy core; the outer planet orbits within the habitable zone of this star.

  17. Rapid heating of the atmosphere of an extrasolar planet.

    Science.gov (United States)

    Laughlin, Gregory; Deming, Drake; Langton, Jonathan; Kasen, Daniel; Vogt, Steve; Butler, Paul; Rivera, Eugenio; Meschiari, Stefano

    2009-01-29

    Near-infrared observations of more than a dozen 'hot-Jupiter' extrasolar planets have now been reported. These planets display a wide diversity of properties, yet all are believed to have had their spin periods tidally spin-synchronized with their orbital periods, resulting in permanent star-facing hemispheres and surface flow patterns that are most likely in equilibrium. Planets in significantly eccentric orbits can enable direct measurements of global heating that are largely independent of the details of the hydrodynamic flow. Here we report 8-microm photometric observations of the planet HD 80606b during a 30-hour interval bracketing the periastron passage of its extremely eccentric 111.4-day orbit. As the planet received its strongest irradiation (828 times larger than the flux received at apastron) its maximum 8-microm brightness temperature increased from approximately 800 K to approximately 1,500 K over a six-hour period. We also detected a secondary eclipse for the planet, which implies an orbital inclination of i approximately 90 degrees , fixes the planetary mass at four times the mass of Jupiter, and constrains the planet's tidal luminosity. Our measurement of the global heating rate indicates that the radiative time constant at the planet's 8-microm photosphere is approximately 4.5 h, in comparison with 3-5 days in Earth's stratosphere.

  18. ANISOTROPIC WINDS FROM CLOSE-IN EXTRASOLAR PLANETS

    International Nuclear Information System (INIS)

    Stone, James M.; Proga, Daniel

    2009-01-01

    We present two-dimensional hydrodynamic models of thermally driven winds from highly irradiated, close-in extrasolar planets. We adopt a very simple treatment of the radiative heating processes at the base of the wind, and instead focus on the differences between the properties of outflows in multidimensions in comparison to spherically symmetric models computed with the same methods. For hot (T ∼> 2 x 10 4 K) or highly ionized gas, we find that strong (supersonic) polar flows are formed above the planet surface which produce weak shocks and outflow on the night side. In comparison to a spherically symmetric wind with the same parameters, the sonic surface on the day side is much closer to the planet surface in multidimensions, and the total mass-loss rate is reduced by almost a factor of 4. We also compute the steady-state structure of interacting planetary and stellar winds. Both winds end in a termination shock, with a parabolic contact discontinuity which is draped over the planet separating the two shocked winds. The planetary wind termination shock and the sonic surface in the wind are well separated, so that the mass-loss rate from the planet is essentially unaffected. However, the confinement of the planetary wind to the small volume bounded by the contact discontinuity greatly enhances the column density close to the planet, which might be important for the interpretation of observations of absorption lines formed by gas surrounding transiting planets.

  19. DETECTING OCEANS ON EXTRASOLAR PLANETS USING THE GLINT EFFECT

    International Nuclear Information System (INIS)

    Robinson, Tyler D.; Meadows, Victoria S.; Crisp, David

    2010-01-01

    Glint, the specular reflection of sunlight off Earth's oceans, may reveal the presence of oceans on an extrasolar planet. As an Earth-like planet nears crescent phases, the size of the ocean glint spot increases relative to the fraction of the illuminated disk, while the reflectivity of this spot increases. Both effects change the planet's visible reflectivity as a function of phase. However, strong forward scattering of radiation by clouds can also produce increases in a planet's reflectivity as it approaches crescent phases, and surface glint can be obscured by Rayleigh scattering and atmospheric absorption. Here, we explore the detectability of glint in the presence of an atmosphere and realistic phase-dependent scattering from oceans and clouds. We use the NASA Astrobiology Institute's Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model to simulate Earth's broadband visible brightness and reflectivity over an orbit. Our validated simulations successfully reproduce phase-dependent Earthshine observations. We find that the glinting Earth can be as much as 100% brighter at crescent phases than simulations that do not include glint, and that the effect is dependent on both orbital inclination and wavelength, where the latter dependence is caused by Rayleigh scattering limiting sensitivity to the surface. We show that this phenomenon may be observable using the James Webb Space Telescope paired with an external occulter.

  20. Extrasolar Planet Transits Observed at Kitt Peak National Observatory

    Science.gov (United States)

    Sada, Pedro V.; Jennings, Donald E.; Deming, Drake; Jennings, Donald E.; Jackson, Brian; Hamilton, Catrina M.; Fraine, Jonathan; Peterson, Steven W.; Haase, Flynn; Bays, Kevin; hide

    2012-01-01

    We obtained J-, H-, and JH-band photometry of known extrasolar planet transiting systems at the 2.1 m Kitt Peak National Observatory Telescope using the FLAMINGOS infrared camera between 2008 October and 2011 October. From the derived light curves we have extracted the midtransit times, transit depths and transit durations for these events. The precise midtransit times obtained help improve the orbital periods and also constrain transit-time variations of the systems. For most cases the published system parameters successfully accounted for our observed light curves, but in some instances we derive improved planetary radii and orbital periods. We complemented our 2.1 m infrared observations using CCD z0-band and B-band photometry (plus two H(alpha) filter observations) obtained with the Kitt Peak Visitor Center Telescope, and with four H-band transits observed in 2007 October with the NSO's 1.6 m McMath-Pierce Solar Telescope. The principal highlights of our results are (1) Our ensemble of J-band planetary radii agree with optical radii, with the best-fit relation being RpRJ0:0017 0:979RpRvis. (2) We observe starspot crossings during the transit of WASP-11HAT-P-10. (3) We detect starspot crossings by HAT-P-11b (Kepler-3b), thus confirming that the magnetic evolution of the stellar active regions can be monitored even after the Kepler mission has ended. (4) We confirm a grazing transit for HAT-P-27WASP-40. In total, we present 57 individual transits of 32 known exoplanet systems.

  1. Direct Imaging Search for Extrasolar Planets in the Pleiades

    Science.gov (United States)

    Yamamoto, Kodai; Matsuo, Taro; Shibai, Hiroshi; Itoh, Yoichi; Konishi, Mihokko; Sudo, Jun; Tanii, Ryoko; Fukagawa, Misato; Sumi, Takahiro; Kudo, Tomoyuki; hide

    2013-01-01

    We carried out an imaging survey for extrasolar planets around stars in the Pleiades (125 Myr, 135 pc) in the H and K(sub S) bands using HiCIAO combined with adaptive optics, AO188, on the Subaru telescope. We found 13 companion candidates fainter than 14.5 mag in the H band around 9 stars. Five of these 13 were confirmed to be background stars by measurement of their proper motion. One was not found in the second epoch observation, and thus was not a background or companion object. One had multi-epoch images, but the precision of its proper motion was not sufficient to conclude whether it was a background object. Four other candidates are waiting for second-epoch observations to determine their proper motion. Finally, the remaining two were confirmed to be 60 M(sub J) brown dwarf companions orbiting around HD 23514 (G0) and HII 1348 (K5), respectively, as had been reported in previous studies. In our observations, the average detection limit for a point source was 20.3 mag in the H band beyond 1.'' 5 from the central star. On the basis of this detection limit, we calculated the detection efficiency to be 90% for a planet with 6 to 12 Jovian masses and a semi-major axis of 50–1000 AU. For this reason we extrapolated the distribution of the planet mass and the semi-major axis derived from radial velocity observations, and adopted the planet evolution model Baraffe et al. (2003, A&A, 402, 701). Since there was no detection of a planet, we estimated the frequency of such planets to be less than 17.9% (2 sigma) around one star of the Pleiades cluster.

  2. EXTRASOLAR BINARY PLANETS. II. DETECTABILITY BY TRANSIT OBSERVATIONS

    International Nuclear Information System (INIS)

    Lewis, K. M.; Ida, S.; Ochiai, H.; Nagasawa, M.

    2015-01-01

    We discuss the detectability of gravitationally bound pairs of gas-giant planets (which we call “binary planets”) in extrasolar planetary systems that are formed through orbital instability followed by planet–planet dynamical tides during their close encounters, based on the results of N-body simulations by Ochiai et al. (Paper I). Paper I showed that the formation probability of a binary is as much as ∼10% for three giant planet systems that undergo orbital instability, and after post-capture long-term tidal evolution, the typical binary separation is three to five times the sum of the physical radii of the planets. The binary planets are stable during the main-sequence lifetime of solar-type stars, if the stellarcentric semimajor axis of the binary is larger than 0.3 AU. We show that detecting modulations of transit light curves is the most promising observational method to detect binary planets. Since the likely binary separations are comparable to the stellar diameter, the shape of the transit light curve is different from transit to transit, depending on the phase of the binary’s orbit. The transit durations and depth for binary planet transits are generally longer and deeper than those for the single planet case. We point out that binary planets could exist among the known inflated gas-giant planets or objects classified as false positive detections at orbital radii ≳0.3 AU, propose a binary planet explanation for the CoRoT candidate SRc01 E2 1066, and show that binary planets are likely to be present in, and could be detected using, Kepler-quality data

  3. Habitability in the Solar System and on Extrasolar Planets and Moons

    Science.gov (United States)

    McKay, Christopher P.

    2015-01-01

    The criteria for a habitable world initially was based on Earth and centered around liquid water on the surface, warmed by a Sun-like star. The moons of the outer Solar System, principally Europa and Enceladus, have demonstrated that liquid water can exist below the surface warmed by tidal forces from a giant planet. Titan demonstrates that surface liquids other than water - liquid methane/ethane - may be common on other worlds. Considering the numerous extrasolar planets so far discovered and the prospect of discovering extrasolar moons it is timely to reconsider the possibilities for habitability in the Solar System and on extrasolar planets and moons and enumerate the attributes and search methods for detecting habitable worlds and evidence of life.

  4. The Blue Dot Workshop: Spectroscopic Search for Life on Extrasolar Planets

    Science.gov (United States)

    Des Marais, David J. (Editor)

    1997-01-01

    This workshop explored the key questions and challenges associated with detecting life on an extrasolar planet. The final product will be a NASA Conference Publication which includes the abstracts from 21 talks, summaries of key findings, and recommendations for future research. The workshop included sessions on three related topics: the biogeochemistry of biogenic gases in the atmosphere, the chemistry and spectroscopy of planetary atmospheres, and the remote sensing of planetary atmospheres and surfaces. With the observation that planetary formation is probably a common phenomenon, together with the advent of the technical capability to locate and describe extrasolar planets, this research area indeed has an exciting future.

  5. Meteorologies of brown dwarfs and extrasolar giant planets

    Science.gov (United States)

    Cooper, Curtis Steven

    2006-06-01

    This dissertation explores the consequences of atmospheric dynamics for observations of substellar mass objects (SMOs). Discussed first is the growth of cloud particles of various compositions in brown dwarfs of different surface gravities and effective temperatures. The structure of these objects is calculated with a one-dimensional radiative transfer model. To determine particle sizes, the timescales for microphysical growth processes, including nucleation, coagulation, and coalescence, are compared to the timescale for gravitational sedimentation. The model also allows for sustained uplifting of condensable vapor in convective regions. The results show that particle sizes vary greatly over the range of objects studied. In most cases, clouds on brown dwarfs do not dominate the opacity. Rather, they smooth the emergent spectrum and partially redistribute the radiative energy. The focus then shifts to extrasolar giant planets (EGPs). Results are presented from a three-dimensional model of atmospheric dynamics on the transiting Jupiter-like planet HD 209458b. As a close-in orbiter (known as a "roaster"), HD 209458b is super-heated on its dayside. Due to tidal locking of the interior, the dayside hemisphere faces the star in perpetuity, which leads to very different dynamics than is seen on Jupiter. The flow is characterized by an eastward supersonic jet ( u ~ 4 kms - 1 ) extending from the equator to the mid-latitudes. Temperature contrasts are ~500 K at the photosphere. At 220 mbar, winds blow the hottest regions downstream from the substellar point by ~60°, with direct implications for the infrared light curve. These simulations are extended to the study of carbon chemistry in HD 209458b's atmosphere by coupling the CO/CH 4 reaction kinetics to the dynamics. Disequilibrium results from slow reaction rates at low temperatures and pressures. Effective vertical quenching near the ~3 bar level leads to uniformly high concentrations of CO at the photosphere, even in

  6. Extrasolar Giant Planet in Earth-like Orbit

    Science.gov (United States)

    1999-07-01

    Discovery from a Long-term Project at La Silla A new extrasolar planet has been found at the ESO La Silla Observatory as a companion to iota Horologii (iota Hor) . This 5.4-mag solar-type star is located at a distance of 56 light-years and is just visible to the unaided eye in the southern constellation Horologium (The Pendulum Clock). The discovery is the result of a long-term survey of forty solar-type stars that was begun in November 1992. It is based on highly accurate measurements of stellar radial velocities, i.e. the speed with which a star moves along the line of sight. The presence of a planet in orbit around a star is inferred from observed, regular changes of this velocity, as the host star and its planet revolve around a common center of gravity. Since in all cases the star is much heavier than the planet, the resulting velocity variations of the star are always quite small. The team that found the new planet, now designated iota Hor b , consists of Martin Kürster , Michael Endl and Sebastian Els (ESO-Chile), Artie P. Hatzes and William D. Cochran (University of Texas, Austin, USA), and Stefan Döbereiner and Konrad Dennerl (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany). Iodine cell provides very accurate velocity measurements iota Hor b represents the first discovery of an extrasolar planet with an ESO instrument [1]. The finding is based on data obtained with ESO's highest-resolution spectrograph, the Coudé Echelle Spectrometer (CES) at the 1.4-m Coudé Auxiliary Telescope (CAT). While this telescope has recently been decommissioned, the CES instrument is now coupled via an optical fiber link to the larger ESO 3.6-m telescope, thus permitting the continuation of this survey. The high precision radial velocity measurements that are necessary for a study of this type were achieved by means of a special calibration technique. It incorporates an iodine gas absorption cell and sophisticated data modelling. The cell is used like

  7. THE DISCOVERY OF THE MOST METAL-RICH WHITE DWARF: COMPOSITION OF A TIDALLY DISRUPTED EXTRASOLAR DWARF PLANET

    International Nuclear Information System (INIS)

    Dufour, P.; Fontaine, G.; Bergeron, P.; Lachapelle, F.-R.; Kilic, M.; Kleinman, S. J.; Leggett, S. K.

    2010-01-01

    Cool white dwarf stars are usually found to have an outer atmosphere that is practically pure in hydrogen or helium. However, a small fraction have traces of heavy elements that must originate from the accretion of extrinsic material, most probably circumstellar matter. Upon examining thousands of Sloan Digital Sky Survey (SDSS) spectra, we discovered that the helium-atmosphere white dwarf SDSS J073842.56+183509.6 shows the most severe metal pollution ever seen in the outermost layers of such stars. We present here a quantitative analysis of this exciting star by combining high signal-to-noise ratio follow-up spectroscopic and photometric observations with model atmospheres and evolutionary models. We determine the global structural properties of our target star, as well as the abundances of the most significant pollutants in its atmosphere, i.e., H, O, Na, Mg, Si, Ca, and Fe. The relative abundances of these elements imply that the source of the accreted material has a composition similar to that of Bulk Earth. We also report the signature of a circumstellar disk revealed through a large infrared excess in JHK photometry. Combined with our inferred estimate of the mass of the accreted material, this strongly suggests that we are witnessing the remains of a tidally disrupted extrasolar body that was as large as Ceres.

  8. EUV-driven ionospheres and electron transport on extrasolar giant planets orbiting active stars

    Science.gov (United States)

    Chadney, J. M.; Galand, M.; Koskinen, T. T.; Miller, S.; Sanz-Forcada, J.; Unruh, Y. C.; Yelle, R. V.

    2016-03-01

    The composition and structure of the upper atmospheres of extrasolar giant planets (EGPs) are affected by the high-energy spectrum of their host stars from soft X-rays to the extreme ultraviolet (EUV). This emission depends on the activity level of the star, which is primarily determined by its age. In this study, we focus upon EGPs orbiting K- and M-dwarf stars of different ages - ɛ Eridani, AD Leonis, AU Microscopii - and the Sun. X-ray and EUV (XUV) spectra for these stars are constructed using a coronal model. These spectra are used to drive both a thermospheric model and an ionospheric model, providing densities of neutral and ion species. Ionisation - as a result of stellar radiation deposition - is included through photo-ionisation and electron-impact processes. The former is calculated by solving the Lambert-Beer law, while the latter is calculated from a supra-thermal electron transport model. We find that EGP ionospheres at all orbital distances considered (0.1-1 AU) and around all stars selected are dominated by the long-lived H+ ion. In addition, planets with upper atmospheres where H2 is not substantially dissociated (at large orbital distances) have a layer in which H3+ is the major ion at the base of the ionosphere. For fast-rotating planets, densities of short-lived H3+ undergo significant diurnal variations, with the maximum value being driven by the stellar X-ray flux. In contrast, densities of longer-lived H+ show very little day/night variability and the magnitude is driven by the level of stellar EUV flux. The H3+ peak in EGPs with upper atmospheres where H2 is dissociated (orbiting close to their star) under strong stellar illumination is pushed to altitudes below the homopause, where this ion is likely to be destroyed through reactions with heavy species (e.g. hydrocarbons, water). The inclusion of secondary ionisation processes produces significantly enhanced ion and electron densities at altitudes below the main EUV ionisation peak, as

  9. Views from EPOXI: Colors in Our Solar System as an Analog for Extrasolar Planets

    Science.gov (United States)

    Crow, Carolyn A.; McFadden, L. A.; Robinson, T.; Meadows, V. S.; Livengood, T. A.; Hewagama, T.; Barry, R. K.; Deming, L. D.; Lisse, C. M.; Wellnitz, Dennis

    2011-01-01

    The first visible-light studies of Earth-sized extrasolar planets will employ photometry or low-resolution spectroscopy. This work uses EPOCh medium-hand filter photometry between 150 and 950 nm obtained with the Deep Impact (DI) High Resolution Instrument (HRI) of Earth, the Moon, and Mars in addition to previous full-disk observations of the other six solar system planets and Titan to analyze the limitations of using photometric colors to characterize extrasolar planets. We determined that the HRI 350, 550, and 850 nm filters are optimal for distinguishing Earth from the other planets and separating planets to first order based on their atmospheric and surface properties. Detailed conclusions that can be drawn about exoplanet atmospheres simply from a color-color plot are limited due to potentially competing physical processes in the atmosphere. The presence of a Rayleigh scattering atmosphere can be detected by an increase in the 350-550 nm brightness ratio, but the absence of Rayleigh scattering cannot be confirmed due to the existence of atmospheric and surface absorbing species in the UV. Methane and ammonia are the only species responsible for strong absorption in the 850 nm filter in our solar system. The combination of physical processes present on extrasolar planets may differ from those we see locally. Nevertheless, a generation of telescopes capable of collecting such photometric observations can serve a critical role in first-order characterization and constraining the population of Earth-like extrasolar planets.

  10. Characterization of extra-solar planets with direct-imaging techniques

    NARCIS (Netherlands)

    Tinetti, G.; Cash, W.; Glassman, T.; Keller, C.U.; Oakley, P.; Snik, F.; Stam, D.; Turnbull, M.

    2009-01-01

    In order to characterize the physical properties of an extra-solar planet one needs to detect planetary radiation, either visible (VIS) to near-infrared (NIR) reflected starlight or infrared (IR) thermal radiation. Both the reflected and thermal flux depend on the size of the planet, the distance

  11. Integrating polarized light over a planetary disk applied to starlight reflected by extrasolar planets

    NARCIS (Netherlands)

    Stam, D.M.; de Rooij, W.A.; Cornet, G.; Hovenier, J.W.

    2006-01-01

    We present an efficient numerical method for integrating planetary radiation over a planetary disk, which is especially interesting for simulating signals of extrasolar planets. Our integration method is applicable to calculating the full flux vector of the disk-integrated planetary radiation, i.e.

  12. Evidence for water in the rocky debris of a disrupted extrasolar minor planet.

    Science.gov (United States)

    Farihi, J; Gänsicke, B T; Koester, D

    2013-10-11

    The existence of water in extrasolar planetary systems is of great interest because it constrains the potential for habitable planets and life. We have identified a circumstellar disk that resulted from the destruction of a water-rich and rocky extrasolar minor planet. The parent body formed and evolved around a star somewhat more massive than the Sun, and the debris now closely orbits the white dwarf remnant of the star. The stellar atmosphere is polluted with metals accreted from the disk, including oxygen in excess of that expected for oxide minerals, indicating that the parent body was originally composed of 26% water by mass. This finding demonstrates that water-bearing planetesimals exist around A- and F-type stars that end their lives as white dwarfs.

  13. Darwin--a mission to detect and search for life on extrasolar planets.

    Science.gov (United States)

    Cockell, C S; Léger, A; Fridlund, M; Herbst, T M; Kaltenegger, L; Absil, O; Beichman, C; Benz, W; Blanc, M; Brack, A; Chelli, A; Colangeli, L; Cottin, H; Coudé du Foresto, F; Danchi, W C; Defrère, D; den Herder, J-W; Eiroa, C; Greaves, J; Henning, T; Johnston, K J; Jones, H; Labadie, L; Lammer, H; Launhardt, R; Lawson, P; Lay, O P; LeDuigou, J-M; Liseau, R; Malbet, F; Martin, S R; Mawet, D; Mourard, D; Moutou, C; Mugnier, L M; Ollivier, M; Paresce, F; Quirrenbach, A; Rabbia, Y D; Raven, J A; Rottgering, H J A; Rouan, D; Santos, N C; Selsis, F; Serabyn, E; Shibai, H; Tamura, M; Thiébaut, E; Westall, F; White, G J

    2009-01-01

    The discovery of extrasolar planets is one of the greatest achievements of modern astronomy. The detection of planets that vary widely in mass demonstrates that extrasolar planets of low mass exist. In this paper, we describe a mission, called Darwin, whose primary goal is the search for, and characterization of, terrestrial extrasolar planets and the search for life. Accomplishing the mission objectives will require collaborative science across disciplines, including astrophysics, planetary sciences, chemistry, and microbiology. Darwin is designed to detect rocky planets similar to Earth and perform spectroscopic analysis at mid-infrared wavelengths (6-20 mum), where an advantageous contrast ratio between star and planet occurs. The baseline mission is projected to last 5 years and consists of approximately 200 individual target stars. Among these, 25-50 planetary systems can be studied spectroscopically, which will include the search for gases such as CO(2), H(2)O, CH(4), and O(3). Many of the key technologies required for the construction of Darwin have already been demonstrated, and the remainder are estimated to be mature in the near future. Darwin is a mission that will ignite intense interest in both the research community and the wider public.

  14. Transits of extrasolar moons around luminous giant planets

    Science.gov (United States)

    Heller, R.

    2016-04-01

    Beyond Earth-like planets, moons can be habitable, too. No exomoons have been securely detected, but they could be extremely abundant. Young Jovian planets can be as hot as late M stars, with effective temperatures of up to 2000 K. Transits of their moons might be detectable in their infrared photometric light curves if the planets are sufficiently separated (≳10 AU) from the stars to be directly imaged. The moons will be heated by radiation from their young planets and potentially by tidal friction. Although stellar illumination will be weak beyond 5 AU, these alternative energy sources could liquify surface water on exomoons for hundreds of Myr. A Mars-mass H2O-rich moon around β Pic b would have a transit depth of 1.5 × 10-3, in reach of near-future technology.

  15. Heavy leptons

    International Nuclear Information System (INIS)

    Smith, C.H.L.

    1977-01-01

    The possibility that a new lepton may exist is discussed under the headings; theoretical reasons for the introduction of heavy leptons, classification of heavy leptons (ortho and paraleptons), discrimination between different types of lepton, decays of charged heavy leptons, production of charged heavy leptons (in e + e - storage rings, neutrino production, photoproduction, and hadroproduction), neutral heavy leptons, and hadroleptons. (U.K.)

  16. ROCKY EXTRASOLAR PLANETARY COMPOSITIONS DERIVED FROM EXTERNALLY POLLUTED WHITE DWARFS

    International Nuclear Information System (INIS)

    Klein, B.; Jura, M.; Zuckerman, B.; Koester, D.

    2011-01-01

    We report Keck High Resolution Echelle Spectrometer data and model atmosphere analysis of two helium-dominated white dwarfs, PG1225–079 and HS2253+8023, whose heavy pollutions most likely derive from the accretion of terrestrial-type planet(esimal)s. For each system, the minimum accreted mass is ∼10 22 g, that of a large asteroid. In PG1225–079, Mg, Cr, Mn, Fe, and Ni have abundance ratios similar to bulk Earth values, while we measure four refractory elements, Ca, Sc, Ti, and V, all at a factor of ∼2-3 higher abundance than in the bulk Earth. For HS2253+8023 the swallowed material was compositionally similar to bulk Earth in being more than 85% by mass in the major element species, O, Mg, Si, and Fe, and with abundances in the distinctive proportions of mineral oxides—compelling evidence for an origin in a rocky parent body. Including previous studies we now know of four heavily polluted white dwarfs where the measured oxygen and hydrogen are consistent with the view that the parents' bodies formed with little ice, interior to any snow line in their nebular environments. The growing handful of polluted white dwarf systems with comprehensive abundance measurements form a baseline for characterizing rocky exoplanet compositions that can be compared with bulk Earth.

  17. On the feasibility of detecting extrasolar planets by reflected starlight using the Hubble Space Telescope

    Science.gov (United States)

    Brown, Robert A.; Burrows, Christopher J.

    1990-01-01

    The best metrology data extant are presently used to estimate the center and wing point-spread function of the HST, in order to ascertain the implications of an observational criterion according to which a faint source's discovery can occur only when the signal recorded near its image's location is sufficiently larger than would be expected in its absence. After defining the maximum star-planet flux ratio, a figure of merit Q, defined as the contrast ratio between a 'best case' planet and the scattered starlight background, is introduced and shown in the HST's case to be unfavorable for extrasolar planet detection.

  18. Characterization of extra-solar planets with direct-imaging techniques

    OpenAIRE

    Tinetti, G.; Cash, W.; Glassman, T.; Keller, C.U.; Oakley, P.; Snik, F.; Stam, D.; Turnbull, M.

    2009-01-01

    In order to characterize the physical properties of an extra-solar planet one needs to detect planetary radiation, either visible (VIS) to near-infrared (NIR) reflected starlight or infrared (IR) thermal radiation. Both the reflected and thermal flux depend on the size of the planet, the distance between the planet and the star, the distance between the observer and the planet, and the planet’s phase angle (i.e. the angle between the star and the observer as seen from the planet). Moreover, t...

  19. The changing phases of extrasolar planet CoRoT-1b.

    Science.gov (United States)

    Snellen, Ignas A G; de Mooij, Ernst J W; Albrecht, Simon

    2009-05-28

    Hot Jupiters are a class of extrasolar planet that orbit their parent stars at very short distances. They are expected to be tidally locked, which can lead to a large temperature difference between their daysides and nightsides. Infrared observations of eclipsing systems have yielded dayside temperatures for a number of transiting planets. The day-night contrast of the transiting extrasolar planet HD 189733b was 'mapped' using infrared observations. It is expected that the contrast between the daysides and nightsides of hot Jupiters is much higher at visual wavelengths, shorter than that of the peak emission, and could be further enhanced by reflected stellar light. Here we report the analysis of optical photometric data obtained over 36 planetary orbits of the transiting hot Jupiter CoRoT-1b. The data are consistent with the nightside hemisphere of the planet being entirely black, with the dayside flux dominating the optical phase curve. This means that at optical wavelengths the planet's phase variation is just as we see it for the interior planets in the Solar System. The data allow for only a small fraction of reflected light, corresponding to a geometric albedo of <0.20.

  20. A Spitzer Infrared Radius for the Transiting Extrasolar Planet HD 209458 b

    Science.gov (United States)

    Richardson, L. Jeremy; Harrington, Joseph; Seager, Sara; Deming, Drake

    2007-01-01

    We have measured the infrared transit of the extrasolar planet HD 209458 b using the Spitzer Space Telescope. We observed two primary eclipse events (one partial and one complete transit) using the 24 micrometer array of the Multiband Imaging Photometer for Spitzer (MIPS). We analyzed a total of 2392 individual images (10-second integrations) of the planetary system, recorded before, during, and after transit. We perform optimal photometry on the images and use the local zodiacal light as a short-term flux reference. At this long wavelength, the transit curve has a simple box-like shape, allowing robust solutions for the stellar and planetary radii independent of stellar limb darkening, which is negligible at 24 micrometers. We derive a stellar radius of R(sub *) = 1.06 plus or minus 0.07 solar radius, a planetary radius of R(sub p) = 1.26 plus or minus 0.08 R(sub J), and a stellar mass of 1.17 solar mass. Within the errors, our results agree with the measurements at visible wavelengths. The 24 micrometer radius of the planet therefore does not differ significantly compared to the visible result. We point out the potential for deriving extrasolar transiting planet radii to high accuracy using transit photometry at slightly shorter IR wavelengths where greater photometric precision is possible.

  1. The evolution of comets and the detectability of Extra-Solar Oort Clouds

    International Nuclear Information System (INIS)

    Stern, S.A.

    1989-01-01

    According the standard theory, comets are natural products of solar system formation, ejected to the Oort Cloud by gravitational scattering events during the epoch of giant planet formation. Stored far from the Sun for billions of years, comets almost certainly contain a record of the events which occurred during (and perhaps even before) the epoch of planetary formation. Two themes are examined of the evolutionary processes that affect comets in the Oort Cloud, and a search for evidence of Extra-Solar Oort Clouds (ESOCs). With regard to cometary evolution in the Oort Cloud, it was found that luminous O stars and supernovae have heated the surface layers of all comets on numerous occasions to 20 to 30 K and perhaps once to 50 K. Interstellar medium (ISM) interactions blow small grains out of the Oort Clouds, and erode the upper few hundred g/cu cm of material from cometary surfaces. The findings presented contradict the standard view that comets do not undergo physical change in the Oort Cloud. A logical consequence of the intimate connection between the Oort Cloud and our planetary system is that the detection of comet clouds around other stars would strongly indicate the sites of extant extra-solar planetary systems. A search was conducted for infrared IR emission from debris in ESOCs. After examining 17 stars using the Infrared Astronomical Satellite data base, only upper limits on ESOC emission could be set

  2. Late Budgets

    DEFF Research Database (Denmark)

    Andersen, Asger Lau; Lassen, David Dreyer; Nielsen, Lasse Holbøll Westh

    are negative rather than positive; and when there is divided government. We test the hypotheses of the model using a unique data set of late budgets for US state governments, based on dates of budget approval collected from news reports and a survey of state budget o¢ cers for the period 1988...

  3. Heavy Chain Diseases

    Science.gov (United States)

    ... of heavy chain produced: Alpha Gamma Mu Alpha Heavy Chain Disease Alpha heavy chain disease (IgA heavy ... the disease or lead to a remission. Gamma Heavy Chain Disease Gamma heavy chain disease (IgG heavy ...

  4. Spectroscopic characterization of extrasolar planets from ground-, space- and airborne-based observatories

    Science.gov (United States)

    Angerhausen, Daniel

    2010-11-01

    This thesis deals with techniques and results of observations of exoplanets from several platforms. In this work I present and then attempt solutions to particular issues and problems connected to ground- and space-based approaches to spectroscopic characterization of extrasolar planets. Furthermore, I present the future prospects of the airborne observatory, SOFIA, in this field of astronomy. The first part of this thesis covers results of an exploratory study to use near-infrared integral-field-spectroscopy to observe transiting extrasolar planets. I demonstrate how adaptive-optics assisted integral field spectroscopy compares with other spectroscopic techniques currently applied, foremost being slit spectroscopy. An advanced reduction method using elements of a spectral-differential decorrelation and optimized observation strategies is discussed. This concept was tested with K-Band time series observations of secondary eclipses of HD 209458b and HD 189733b obtained with the SINFONI at the Very Large Telescope (VLT), at spectral resolution of R~3000. In ground-based near infrared (NIR) observations, there is considerable likelihood of confusion between telluric absorption features and spectral features in the targeted object. I describe a detailed method that can cope with such confusion by a forward modelling approach employing Earth transmission models. In space-based transit spectroscopy with Hubble's NICMOS instrument, the main source of systematic noise is the perturbation in the instrument's configuration due to the near Earth orbital motion of the spacecraft. I present an extension to a pre-existing data analysis sequence that has allowed me to extract a NIR transmission spectrum of the hot-Neptune class planet GJ 436b from a data set that was highly corrupted by the above mentioned effects. Satisfyingly, I was able to obtain statistical consistency in spectra (acquired over a broad wavelength grid) over two distinct observing visits by HST. Earlier

  5. Radiobiological comparison of pions and heavy ions

    International Nuclear Information System (INIS)

    Raju, M.R.

    1981-01-01

    The physical and radiobiological differences between some aspects of pions and heavy ions are discussed, followed by a discussion of acute and late effects of high LET radiations compared to low LET radiations

  6. Three regimes of extrasolar planet radius inferred from host star metallicities

    DEFF Research Database (Denmark)

    Buchhave, Lars A.; Bizzarro, Martin; Latham, David W.

    2014-01-01

    Approximately half of the extrasolar planets (exoplanets) with radii less than four Earth radii are in orbits with short periods. Despite their sheer abundance, the compositions of such planets are largely unknown. The available evidence suggests that they range in composition from small, high......-density rocky planets to low-density planets consisting of rocky cores surrounded by thick hydrogen and helium gas envelopes. Here we report the metallicities (that is, the abundances of elements heavier than hydrogen and helium) of more than 400 stars hosting 600 exoplanet candidates, and find...... that the exoplanets can be categorized into three populations defined by statistically distinct (~4.5σ) metallicity regions. We interpret these regions as reflecting the formation regimes of terrestrial-like planets (radii less than 1.7 Earth radii), gas dwarf planets with rocky cores and hydrogen-helium envelopes...

  7. THE PROJECT: an Observatory / Transport Spaceship for Discovering and Populating Habitable Extrasolar Terrestrial Planets

    Science.gov (United States)

    Kilston, S.

    1998-12-01

    Recent extrasolar planet discoveries and related progress in astrophysics have refined our knowledge of the implications of the Drake equation. The Space Interferometry Mission and the planned Terrestrial Planet Finder will deepen this understanding, and begin pointing the way to places we need to explore at closer range. If the correct resolution of the Fermi paradox regarding intelligent extraterrestrials (``where are they?") is found to lie in the actual scarcity of such beings, it may turn out that we are more advanced than most other life-forms in our galaxy. In this case, a main purpose in finding planets may be to find places for us to go: astronomy will once again play a major role in human navigation and migration. We describe a strawman design concept for an astronomical observatory ship designed for launch beyond our solar system within several hundred years. This ship design would employ plausible physics, biology, technology, sociology, and economics to carry one million passengers in a one-G environment shielded from space radiation. A cruising speed under 0.01 c, slower than in many science-fiction concepts, minimizes power requirements and the danger from collisional impacts. The ship would contain all subsystems needed to sustain multi-generational life on a voyage of thousands of years, as well as the observatories to identify for human settlement a habitable extrasolar planet. Even the modestly advanced technology described here could spread intelligent life throughout our galaxy within 40 million years, a very small fraction of the galaxy's age. Motivation for such an ambitious project is three-fold: expanding our knowledge of the universe, enlisting the efforts and enthusiasms of humankind toward a very grand goal which will stimulate progress in all aspects of our cultures and technologies, and participating in the process of spreading life so its survivability and fruition are enhanced.

  8. Heavy baryons

    International Nuclear Information System (INIS)

    Koerner, J.G.

    1994-06-01

    We review the experimental and theoretical status of baryons containing one heavy quark. The charm and bottom baryon states are classified and their mass spectra are listed. The appropriate theoretical framework for the description of heavy baryons is the Heavy Quark Effective Theory, whose general ideas and methods are introduced and illustrated in specific examples. We present simple covariant expressions for the spin wave functions of heavy baryons including p-wave baryons. The covariant spin wave functions are used to determine the Heavy Quark Symmetry structure of flavour-changing current-induced transitions between heavy baryons as well as one-pion and one-photon transitions between heavy baryons of the same flavour. We discuss 1/m Q corrections to the current-induced transitions as well as the structure of heavy to light baryon transitions. Whenever possible we attempt to present numbers to compare with experiment by making use of further model-dependent assumptions as e.g. the constituent picture for light quarks. We highlight recent advances in the theoretical understanding of the inclusive decays of hadrons containing one heavy quark including polarization. For exclusive semileptonic decays we discuss rates, angular decay distributions and polarization effects. We provide an update of the experimental and theoretical status of lifetimes of heavy baryons and of exclusive nonleptonic two body decays of charm baryons. (orig.)

  9. Late Raphael

    OpenAIRE

    Henry, Tom F. K.; Joannides, Paul; González Mozo, Ana; Martín, Bruno

    2012-01-01

    Exhibition catalogue (co-authored with P. Joannides) in English, Spanish and French by the Museo del Prado and the Musée du Louvre, 2012. English edition, publisher: Museo Nacional del Prado (ISBN 978-84-8480-237-2). 382 pages, of which 300 were co-authored with P. Joannides. This publication was the catalogue of the major exhibtion of Raphael's late work which was at the Prado and the Louvre in 2012-13. The exhibition was seen by more than 650,000 visitors, and was widely reviewed in the int...

  10. Heavy flavors

    International Nuclear Information System (INIS)

    Cox, B.; Gilman, F.J.; Gottschalk, T.D.

    1986-11-01

    A range of issues pertaining to heavy flavors at the SSC is examined including heavy flavor production by gluon-gluon fusion and by shower evolution of gluon jets, flavor tagging, reconstruction of Higgs and W bosons, and the study of rare decays and CP violation in the B meson system. A specific detector for doing heavy flavor physics and tuned to this latter study at the SSC, the TASTER, is described. 36 refs., 10 figs

  11. PLANET-PLANET SCATTERING IN PLANETESIMAL DISKS. II. PREDICTIONS FOR OUTER EXTRASOLAR PLANETARY SYSTEMS

    International Nuclear Information System (INIS)

    Raymond, Sean N.; Armitage, Philip J.; Gorelick, Noel

    2010-01-01

    We develop an idealized dynamical model to predict the typical properties of outer extrasolar planetary systems, at radii comparable to the Jupiter-to-Neptune region of the solar system. The model is based upon the hypothesis that dynamical evolution in outer planetary systems is controlled by a combination of planet-planet scattering and planetary interactions with an exterior disk of small bodies ('planetesimals'). Our results are based on 5000 long duration N-body simulations that follow the evolution of three planets from a few to 10 AU, together with a planetesimal disk containing 50 M + from 10 to 20 AU. For large planet masses (M ∼> M Sat ), the model recovers the observed eccentricity distribution of extrasolar planets. For lower-mass planets, the range of outcomes in models with disks is far greater than that which is seen in isolated planet-planet scattering. Common outcomes include strong scattering among massive planets, sudden jumps in eccentricity due to resonance crossings driven by divergent migration, and re-circularization of scattered low-mass planets in the outer disk. We present the distributions of the eccentricity and inclination that result, and discuss how they vary with planet mass and initial system architecture. In agreement with other studies, we find that the currently observed eccentricity distribution (derived primarily from planets at a ∼ -1 and periods in excess of 10 years will provide constraints on this regime. Finally, we present an analysis of the predicted separation of planets in two-planet systems, and of the population of planets in mean-motion resonances (MMRs). We show that, if there are systems with ∼ Jupiter-mass planets that avoid close encounters, the planetesimal disk acts as a damping mechanism and populates MMRs at a very high rate (50%-80%). In many cases, resonant chains (in particular the 4:2:1 Laplace resonance) are set up among all three planets. We expect such resonant chains to be common among massive

  12. Earth as an extrasolar planet: Earth model validation using EPOXI earth observations.

    Science.gov (United States)

    Robinson, Tyler D; Meadows, Victoria S; Crisp, David; Deming, Drake; A'hearn, Michael F; Charbonneau, David; Livengood, Timothy A; Seager, Sara; Barry, Richard K; Hearty, Thomas; Hewagama, Tilak; Lisse, Carey M; McFadden, Lucy A; Wellnitz, Dennis D

    2011-06-01

    The EPOXI Discovery Mission of Opportunity reused the Deep Impact flyby spacecraft to obtain spatially and temporally resolved visible photometric and moderate resolution near-infrared (NIR) spectroscopic observations of Earth. These remote observations provide a rigorous validation of whole-disk Earth model simulations used to better understand remotely detectable extrasolar planet characteristics. We have used these data to upgrade, correct, and validate the NASA Astrobiology Institute's Virtual Planetary Laboratory three-dimensional line-by-line, multiple-scattering spectral Earth model. This comprehensive model now includes specular reflectance from the ocean and explicitly includes atmospheric effects such as Rayleigh scattering, gas absorption, and temperature structure. We have used this model to generate spatially and temporally resolved synthetic spectra and images of Earth for the dates of EPOXI observation. Model parameters were varied to yield an optimum fit to the data. We found that a minimum spatial resolution of ∼100 pixels on the visible disk, and four categories of water clouds, which were defined by using observed cloud positions and optical thicknesses, were needed to yield acceptable fits. The validated model provides a simultaneous fit to Earth's lightcurve, absolute brightness, and spectral data, with a root-mean-square (RMS) error of typically less than 3% for the multiwavelength lightcurves and residuals of ∼10% for the absolute brightness throughout the visible and NIR spectral range. We have extended our validation into the mid-infrared by comparing the model to high spectral resolution observations of Earth from the Atmospheric Infrared Sounder, obtaining a fit with residuals of ∼7% and brightness temperature errors of less than 1 K in the atmospheric window. For the purpose of understanding the observable characteristics of the distant Earth at arbitrary viewing geometry and observing cadence, our validated forward model can be

  13. Fast spin of the young extrasolar planet β Pictoris b.

    Science.gov (United States)

    Snellen, Ignas A G; Brandl, Bernhard R; de Kok, Remco J; Brogi, Matteo; Birkby, Jayne; Schwarz, Henriette

    2014-05-01

    The spin of a planet arises from the accretion of angular momentum during its formation, but the details of this process are still unclear. In the Solar System, the equatorial rotation velocities and, consequently, spin angular momenta of most of the planets increase with planetary mass; the exceptions to this trend are Mercury and Venus, which, since formation, have significantly spun down because of tidal interactions. Here we report near-infrared spectroscopic observations, at a resolving power of 100,000, of the young extrasolar gas giant planet β Pictoris b (refs 7, 8). The absorption signal from carbon monoxide in the planet's thermal spectrum is found to be blueshifted with respect to that from the parent star by approximately 15 kilometres per second, consistent with a circular orbit. The combined line profile exhibits a rotational broadening of about 25 kilometres per second, meaning that β Pictoris b spins significantly faster than any planet in the Solar System, in line with the extrapolation of the known trend in spin velocity with planet mass.

  14. Detecting Close-In Extrasolar Giant Planets with the Kepler Photometer via Scattered Light

    Science.gov (United States)

    Jenkins, J. M.; Doyle, L. R.; Kepler Discovery Mission Team

    2003-05-01

    NASA's Kepler Mission will be launched in 2007 primarily to search for transiting Earth-sized planets in the habitable zones of solar-like stars. In addition, it will be poised to detect the reflected light component from close-in extrasolar giant planets (CEGPs) similar to 51 Peg b. Here we use the DIARAD/SOHO time series along with models for the reflected light signatures of CEGPs to evaluate Kepler's ability to detect such planets. We examine the detectability as a function of stellar brightness, stellar rotation period, planetary orbital inclination angle, and planetary orbital period, and then estimate the total number of CEGPs that Kepler will detect over its four year mission. The analysis shows that intrinsic stellar variability of solar-like stars is a major obstacle to detecting the reflected light from CEGPs. Monte Carlo trials are used to estimate the detection threshold required to limit the total number of expected false alarms to no more than one for a survey of 100,000 stellar light curves. Kepler will likely detect 100-760 51 Peg b-like planets by reflected light with orbital periods up to 7 days. LRD was supported by the Carl Sagan Chair at the Center for the Study of Life in the Universe, a division of the SETI Institute. JMJ received support from the Kepler Mission Photometer and Science Office at NASA Ames Research Center.

  15. Investigating Extra-solar Planetary System Qatar-1 through Transit Observations

    Science.gov (United States)

    Thakur, Parijat; Mannaday, Vineet Kumar; Jiang, Ing-Guey; Sahu, Devendra Kumar; Chand, Swadesh

    2018-04-01

    We report the results of the transit timing variation (TTV) analysis of the extra-solar planet Qatar-1b using thirty eight light curves. Our analysis combines thirty five previously available transit light curves with three new transits observed by us between June 2016 and September 2016 using the 2-m Himalayan Chandra Telescope (HCT) at the Indian Astronomical Observatory (Hanle, India). From these transit data, the physical and orbital parameters of the Qatar-1 system are determined. In addition to this, the ephemeris for the orbital period and mid-transit time are refined to investigate the possible TTV. We find that the null-TTV model provides the better fit to the (O-C) data. This indicates that there is no evidence for TTVs to confirm the presence of additional planets in the Qatar-1 system. The use of the 3.6-m Devasthal Optical Telescope (DOT) operated by the Aryabhatta Research Institute of Observational Sciences (ARIES, Nainital, India) could improve the photometric precision to examine the signature of TTVs in this system with a greater accuracy than in the present work.

  16. Three regimes of extrasolar planet radius inferred from host star metallicities.

    Science.gov (United States)

    Buchhave, Lars A; Bizzarro, Martin; Latham, David W; Sasselov, Dimitar; Cochran, William D; Endl, Michael; Isaacson, Howard; Juncher, Diana; Marcy, Geoffrey W

    2014-05-29

    Approximately half of the extrasolar planets (exoplanets) with radii less than four Earth radii are in orbits with short periods. Despite their sheer abundance, the compositions of such planets are largely unknown. The available evidence suggests that they range in composition from small, high-density rocky planets to low-density planets consisting of rocky cores surrounded by thick hydrogen and helium gas envelopes. Here we report the metallicities (that is, the abundances of elements heavier than hydrogen and helium) of more than 400 stars hosting 600 exoplanet candidates, and find that the exoplanets can be categorized into three populations defined by statistically distinct (∼4.5σ) metallicity regions. We interpret these regions as reflecting the formation regimes of terrestrial-like planets (radii less than 1.7 Earth radii), gas dwarf planets with rocky cores and hydrogen-helium envelopes (radii between 1.7 and 3.9 Earth radii) and ice or gas giant planets (radii greater than 3.9 Earth radii). These transitions correspond well with those inferred from dynamical mass estimates, implying that host star metallicity, which is a proxy for the initial solids inventory of the protoplanetary disk, is a key ingredient regulating the structure of planetary systems.

  17. Testing the Mirror World Hypothesis for the Close-In Extrasolar Planets

    International Nuclear Information System (INIS)

    Foot, R.

    2004-01-01

    Because planets are not expected to be able to form close to stars due to the high temperatures, it has been suggested that the observed close orbiting (∼ 0.05 AU) large mass planets (∼ M J ) might be mirror worlds - planets composed predominately of mirror matter. The accretion of ordinary matter onto the mirror planet (from e.g. the solar wind from the host star) will make the mirror planet opaque to ordinary radiation with an effective radius R p . It was argued in a previous paper, that this radius was potentially large enough to explain the measured size of the first transiting close-in extrasolar planet, HD209458b. Furthermore, made the rough prediction: R p ∝ √ (T s /M p ), where T s is the surface temperature of the ordinary matter in the mirror planet and M p is the mass of the planet (the latter dependence on M p being the more robust prediction). We compare this prediction with the recently discovered transiting planets, OGLE-TR-56b and OGLE-TR- 113b. (author)

  18. Spectral Resolution-linked Bias in Transit Spectroscopy of Extrasolar Planets

    Science.gov (United States)

    Deming, Drake; Sheppard, Kyle

    2017-05-01

    We re-visit the principles of transmission spectroscopy for transiting extrasolar planets, focusing on the overlap between the planetary spectrum and the illuminating stellar spectrum. Virtually all current models of exoplanetary transmission spectra utilize an approximation that is inaccurate when the spectrum of the illuminating star has a complex line structure, such as molecular bands in M-dwarf spectra. In those cases, it is desirable to model the observations using a coupled stellar-planetary radiative transfer model calculated at high spectral resolving power, followed by convolution to the observed resolution. Not consistently accounting for overlap of stellar M-dwarf and planetary lines at high spectral resolution can bias the modeled amplitude of the exoplanetary transmission spectrum, producing modeled absorption that is too strong. We illustrate this bias using the exoplanet TRAPPIST-1b, as observed using Hubble Space Telescope/WFC3. The bias in this case is about 250 ppm, 12% of the modeled transit absorption. Transit spectroscopy using JWST will have access to longer wavelengths where the water bands are intrinsically stronger, and the observed signal-to-noise ratios will be higher than currently possible. We therefore expect that this resolution-linked bias will be especially important for future JWST observations of TESS-discovered super-Earths and mini-Neptunes transiting M-dwarfs.

  19. Atmospheric mass-loss of extrasolar planets orbiting magnetically active host stars

    Science.gov (United States)

    Lalitha, Sairam; Schmitt, J. H. M. M.; Dash, Spandan

    2018-06-01

    Magnetic stellar activity of exoplanet hosts can lead to the production of large amounts of high-energy emission, which irradiates extrasolar planets, located in the immediate vicinity of such stars. This radiation is absorbed in the planets' upper atmospheres, which consequently heat up and evaporate, possibly leading to an irradiation-induced mass-loss. We present a study of the high-energy emission in the four magnetically active planet-bearing host stars, Kepler-63, Kepler-210, WASP-19, and HAT-P-11, based on new XMM-Newton observations. We find that the X-ray luminosities of these stars are rather high with orders of magnitude above the level of the active Sun. The total XUV irradiation of these planets is expected to be stronger than that of well-studied hot Jupiters. Using the estimated XUV luminosities as the energy input to the planetary atmospheres, we obtain upper limits for the total mass- loss in these hot Jupiters.

  20. MIGRATION OF EXTRASOLAR PLANETS: EFFECTS FROM X-WIND ACCRETION DISKS

    International Nuclear Information System (INIS)

    Adams, Fred C.; Cai, Mike J.; Lizano, Susana

    2009-01-01

    Magnetic fields are dragged in from the interstellar medium during the gravitational collapse that forms star/disk systems. Consideration of mean field magnetohydrodynamics in these disks shows that magnetic effects produce sub-Keplerian rotation curves and truncate the inner disk. This Letter explores the ramifications of these predicted disk properties for the migration of extrasolar planets. Sub-Keplerian flow in gaseous disks drives a new migration mechanism for embedded planets and modifies the gap-opening processes for larger planets. This sub-Keplerian migration mechanism dominates over Type I migration for sufficiently small planets (m P ∼ + ) and/or close orbits (r ∼< 1 AU). Although the inclusion of sub-Keplerian torques shortens the total migration time by only a moderate amount, the mass accreted by migrating planetary cores is significantly reduced. Truncation of the inner disk edge (for typical system parameters) naturally explains final planetary orbits with periods P ∼ 4 days. Planets with shorter periods, P ∼ 2 days, can be explained by migration during FU-Orionis outbursts, when the mass accretion rate is high and the disk edge moves inward. Finally, the midplane density is greatly increased at the inner truncation point of the disk (the X-point); this enhancement, in conjunction with continuing flow of gas and solids through the region, supports the in situ formation of giant planets.

  1. Homogeneous Studies of Transiting Extrasolar Planets: Current Status and Future Plans

    Science.gov (United States)

    Taylor, John

    2011-09-01

    We now know of over 500 planets orbiting stars other than our Sun. The jewels in the crown are the transiting planets, for these are the only ones whose masses and radii are measurable. They are fundamental for our understanding of the formation, evolution, structure and atmospheric properties of extrasolar planets. However, their characterization is not straightforward, requiring extremely high-precision photometry and spectroscopy as well as input from theoretical stellar models. I summarize the motivation and current status of a project to measure the physical properties of all known transiting planetary systems using homogeneous techniques (Southworth 2008, 2009, 2010, 2011 in preparation). Careful attention is paid to the treatment of limb darkening, contaminating light, correlated noise, numerical integration, orbital eccentricity and orientation, systematic errors from theoretical stellar models, and empirical constraints. Complete error budgets are calculated for each system and can be used to determine which type of observation would be most useful for improving the parameter measurements. Known correlations between the orbital periods, masses, surface gravities, and equilibrium temperatures of transiting planets can be explored more safely due to the homogeneity of the properties. I give a sneak preview of Homogeneous Studies Paper 4, which includes the properties of thirty transiting planetary systems observed by the CoRoT, Kepler and Deep Impact space missions. Future opportunities are discussed, plus remaining problems with our understanding of transiting planets. I acknowledge funding from the UK STFC in the form of an Advanced Fellowship.

  2. Mechanical Design of NESSI: New Mexico Tech Extrasolar Spectroscopic Survey Instrument

    Science.gov (United States)

    Santoro, Fernando G.; Olivares, Andres M.; Salcido, Christopher D.; Jimenez, Stephen R.; Jurgenson, Colby A.; Hrynevych, Michael A.; Creech-Eakman, Michelle J.; Boston, Penny J.; Schmidt, Luke M.; Bloemhard, Heather; hide

    2011-01-01

    NESSI: the New Mexico Tech Extrasolar Spectroscopic Survey Instrument is a ground-based multi-object spectrograph that operates in the near-infrared. It will be installed on one of the Nasmyth ports of the Magdalena Ridge Observatory (MRO) 2.4-meter Telescope sited in the Magdalena Mountains, about 48 km west of Socorro-NM. NESSI operates stationary to the telescope fork so as not to produce differential flexure between internal opto-mechanical components during or between observations. An appropriate mechanical design allows the instrument alignment to be highly repeatable and stable for both short and long observation timescales, within a wide-range of temperature variation. NESSI is optically composed of a field lens, a field de-rotator, re-imaging optics, an auto-guider and a Dewar spectrograph that operates at LN2 temperature. In this paper we report on NESSI's detailed mechanical and opto-mechanical design, and the planning for mechanical construction, assembly, integration and verification.

  3. BIGRE: A LOW CROSS-TALK INTEGRAL FIELD UNIT TAILORED FOR EXTRASOLAR PLANETS IMAGING SPECTROSCOPY

    International Nuclear Information System (INIS)

    Antichi, Jacopo; Mouillet, David; Puget, Pascal; Beuzit, Jean-Luc; Dohlen, Kjetil; Gratton, Raffaele G.; Mesa, Dino; Claudi, Riccardo U.; Giro, Enrico; Boccaletti, Anthony

    2009-01-01

    Integral field spectroscopy represents a powerful technique for the detection and characterization of extrasolar planets through high-contrast imaging since it allows us to obtain simultaneously a large number of monochromatic images. These can be used to calibrate and then to reduce the impact of speckles, once their chromatic dependence is taken into account. The main concern in designing integral field spectrographs for high-contrast imaging is the impact of the diffraction effects and the noncommon path aberrations together with an efficient use of the detector pixels. We focus our attention on integral field spectrographs based on lenslet arrays, discussing the main features of these designs: the conditions of appropriate spatial and spectral sampling of the resulting spectrograph's slit functions and their related cross-talk terms when the system works at the diffraction limit. We present a new scheme for the integral field unit based on a dual-lenslet device (BIGRE), that solves some of the problems related to the classical Traitement Integral des Galaxies par l'Etude de leurs Rays (TIGER) design when used for such applications. We show that BIGRE provides much lower cross-talk signals than TIGER, allowing a more efficient use of the detector pixels and a considerable saving of the overall cost of a lenslet-based integral field spectrograph.

  4. Spectral Resolution-linked Bias in Transit Spectroscopy of Extrasolar Planets

    Energy Technology Data Exchange (ETDEWEB)

    Deming, Drake; Sheppard, Kyle [Department of Astronomy, University of Maryland at College Park, College Park, MD 20742 (United States)

    2017-05-20

    We re-visit the principles of transmission spectroscopy for transiting extrasolar planets, focusing on the overlap between the planetary spectrum and the illuminating stellar spectrum. Virtually all current models of exoplanetary transmission spectra utilize an approximation that is inaccurate when the spectrum of the illuminating star has a complex line structure, such as molecular bands in M-dwarf spectra. In those cases, it is desirable to model the observations using a coupled stellar–planetary radiative transfer model calculated at high spectral resolving power, followed by convolution to the observed resolution. Not consistently accounting for overlap of stellar M-dwarf and planetary lines at high spectral resolution can bias the modeled amplitude of the exoplanetary transmission spectrum, producing modeled absorption that is too strong. We illustrate this bias using the exoplanet TRAPPIST-1b, as observed using Hubble Space Telescope /WFC3. The bias in this case is about 250 ppm, 12% of the modeled transit absorption. Transit spectroscopy using JWST will have access to longer wavelengths where the water bands are intrinsically stronger, and the observed signal-to-noise ratios will be higher than currently possible. We therefore expect that this resolution-linked bias will be especially important for future JWST observations of TESS-discovered super-Earths and mini-Neptunes transiting M-dwarfs.

  5. WILL THE LARGE SYNOPTIC SURVEY TELESCOPE DETECT EXTRA-SOLAR PLANETESIMALS ENTERING THE SOLAR SYSTEM?

    International Nuclear Information System (INIS)

    Moro-Martin, Amaya; Turner, Edwin L.; Loeb, Abraham

    2009-01-01

    Planetesimal formation is a common by-product of the star formation process. Taking the dynamical history of the solar system as a guideline-in which the planetesimal belts were heavily depleted due to gravitational perturbation with the giant planets-and assuming similar processes have taken place in other planetary systems, one would expect the interstellar space to be filled with extra-solar planetesimals. However, not a single one of these objects has been detected so far entering the solar system, even though it would clearly be distinguishable from a solar system comet due to its highly hyperbolic orbit. The Large Synoptic Survey Telescope (LSST) will provide wide coverage maps of the sky to a very high sensitivity, ideal to detect moving objects like comets, both active and inactive. In anticipation of these observations, we estimate how many inactive 'interstellar comets' might be detected during the duration of the survey. The calculation takes into account estimates (from observations and models) of the number density of stars, the amount of solids available to form planetesimals, the frequency of planet and planetesimal formation, the efficiency of planetesimal ejection, and the possible size distribution of these small bodies.

  6. Spectral Resolution-linked Bias in Transit Spectroscopy of Extrasolar Planets

    International Nuclear Information System (INIS)

    Deming, Drake; Sheppard, Kyle

    2017-01-01

    We re-visit the principles of transmission spectroscopy for transiting extrasolar planets, focusing on the overlap between the planetary spectrum and the illuminating stellar spectrum. Virtually all current models of exoplanetary transmission spectra utilize an approximation that is inaccurate when the spectrum of the illuminating star has a complex line structure, such as molecular bands in M-dwarf spectra. In those cases, it is desirable to model the observations using a coupled stellar–planetary radiative transfer model calculated at high spectral resolving power, followed by convolution to the observed resolution. Not consistently accounting for overlap of stellar M-dwarf and planetary lines at high spectral resolution can bias the modeled amplitude of the exoplanetary transmission spectrum, producing modeled absorption that is too strong. We illustrate this bias using the exoplanet TRAPPIST-1b, as observed using Hubble Space Telescope /WFC3. The bias in this case is about 250 ppm, 12% of the modeled transit absorption. Transit spectroscopy using JWST will have access to longer wavelengths where the water bands are intrinsically stronger, and the observed signal-to-noise ratios will be higher than currently possible. We therefore expect that this resolution-linked bias will be especially important for future JWST observations of TESS-discovered super-Earths and mini-Neptunes transiting M-dwarfs.

  7. Transit detections of extrasolar planets around main-sequence stars. I. Sky maps for hot Jupiters

    Science.gov (United States)

    Heller, R.; Mislis, D.; Antoniadis, J.

    2009-12-01

    Context: The findings of more than 350 extrasolar planets, most of them nontransiting Hot Jupiters, have revealed correlations between the metallicity of the main-sequence (MS) host stars and planetary incidence. This connection can be used to calculate the planet formation probability around other stars, not yet known to have planetary companions. Numerous wide-field surveys have recently been initiated, aiming at the transit detection of extrasolar planets in front of their host stars. Depending on instrumental properties and the planetary distribution probability, the promising transit locations on the celestial plane will differ among these surveys. Aims: We want to locate the promising spots for transit surveys on the celestial plane and strive for absolute values of the expected number of transits in general. Our study will also clarify the impact of instrumental properties such as pixel size, field of view (FOV), and magnitude range on the detection probability. Methods: We used data of the Tycho catalog for ≈1 million objects to locate all the stars with 0^m~≲~m_V~≲~11.5m on the celestial plane. We took several empirical relations between the parameters listed in the Tycho catalog, such as distance to Earth, m_V, and (B-V), and those parameters needed to account for the probability of a star to host an observable, transiting exoplanet. The empirical relations between stellar metallicity and planet occurrence combined with geometrical considerations were used to yield transit probabilities for the MS stars in the Tycho catalog. Magnitude variations in the FOV were simulated to test whether this fluctuations would be detected by BEST, XO, SuperWASP and HATNet. Results: We present a sky map of the expected number of Hot Jupiter transit events on the basis of the Tycho catalog. Conditioned by the accumulation of stars towards the galactic plane, the zone of the highest number of transits follows the same trace, interrupted by spots of very low and high

  8. A Program to Detect and Characterize Extra-Solar Giant Planets

    Science.gov (United States)

    Lindstrom, David (Technical Monitor); Noyes, Robert W.

    2003-01-01

    We initiated a significant hardware upgrade to the AFOE, to increase its efficiency for precise radial velocity studies to the level where we can continue to contribute usefully to extrasolar planet research on relatively bright stars. The AFOE, at a 1.5-m telescope, will of course not have the sensitivity of radial velocity instruments at larger telescopes, such as the HIRES on Keck or the Hectochelle on the MMT telescope (about to come on line). However, it has been possible to increase its efficiency for precise radial velocity studies by a factor of 4 to 5, which-combined with the large amount of telescope time available at the 1.5-m telescope-will permit us to do intensive follow-up observations of stars brighter than about 8 magnitude. The AFOE was originally designed primarily for asteroseismology using a ThAr reference. This provided useful wavelength stability over tens of minutes as required for asteroseismology, but we were unable to get a long-term (month-to-month) velocity precision better than about 15 m/s with that setup. Hence, we implemented an iodine cell as a wavelength reference for extrasolar planet studies. However, the optical design of the original AFOE did not completely span the wavelength range covered by the iodine absorption spectrum, and furthermore the optics suffered significant light loss through optical obscuration in the camera secondary. To remedy this, we replaced the AFOE grating with a new one that covered the entire iodine spectral range at somewhat lower spectral resolution, and replaced the camera with a transmitting lens. (The use of a lens was made possible by restricting the spectral range covered by the upgraded AFOE to only the iodine region.) These upgrades were successfully completed, and the instrument was tested for three nights in fall of 2002. The expected improvement in sensitivity by a factor of 4 to 5 was observed: that is, the same velocity precision as previously attained (of order 5 to 7 m/s) was now

  9. Cloudless Atmospheres for L/T Dwarfs and Extrasolar Giant Planets

    Science.gov (United States)

    Tremblin, P.; Amundsen, D. S.; Chabrier, G.; Baraffe, I.; Drummond, B.; Hinkley, S.; Mourier, P.; Venot, O.

    2016-01-01

    The admitted, conventional scenario to explain the complex spectral evolution of brown dwarfs (BDs) since their first detection 20 years ago has always been the key role played by micron-size condensates, called "dust" or "clouds," in their atmosphere. This scenario, however, faces major problems, in particular the J-band brightening and the resurgence of FeH absorption at the L to T transition, and a physical first-principle understanding of this transition is lacking. In this Letter, we propose a new, completely different explanation for BD and extrasolar giant planet (EGP) spectral evolution, without the need to invoke clouds. We show that, due to the slowness of the CO/ CH4 and N2/NH3 chemical reactions, brown dwarf (L and T, respectively) and EGP atmospheres are subject to a thermo-chemical instability similar in nature to the fingering or chemical convective instability present in Earth oceans and at the Earth core/mantle boundary. The induced small-scale turbulent energy transport reduces the temperature gradient in the atmosphere, explaining the observed increase in near-infrared J-H and J-K colors of L dwarfs and hot EGPs, while a warming up of the deep atmosphere along the L to T transition, as the CO/CH4 instability vanishes, naturally solves the two aforementioned puzzles, and provides a physical explanation of the L to T transition. This new picture leads to a drastic revision of our understanding of BD and EGP atmospheres and their evolution.

  10. Glimpses of far away places: Intensive atmosphere characterization of extrasolar planets

    Science.gov (United States)

    Kreidberg, Laura

    Exoplanet atmosphere characterization has the potential to reveal the origins, nature, and even habitability of distant worlds. This thesis represents a step towards realizing that potential for a diverse group of four extrasolar planets. Here, I present the results of intensive observational campaigns with the Hubble and Spitzer Space Telescopes to study the atmospheres of the super-Earth GJ 1214b and the hot Jupiters WASP-43b, WASP-12b, and WASP-103b. I measured an unprecedentedly precise near-infrared transmission spectrum for GJ 1214b that definitively reveals the presence of clouds in the planet's atmosphere. For WASP-43b and WASP-12b, I also measured very precise spectra that exhibit water features at high confidence (>7 sigma). The retrieved water abundance for WASP-43b extends the well-known Solar System trend of decreasing atmospheric metallicity with increasing planet mass. The detection of water for WASP-12b marks the first spectroscopic identification of a molecule in the planet's atmosphere and implies that it has solar composition, ruling out carbon-to-oxygen ratios greater than unity. For WASP-103b, I present preliminary results from the new technique of phase-resolved spectroscopy to determine the planet's temperature structure, dynamics, and energy budget. In addition to these observations, I also describe the BATMAN code, an open-source Python package for fast and flexible modeling of transit light curves. Taken together, these results provide a foundation for comparative planetology beyond the Solar System and the investigation of Earth-like, potentially habitable planets with future observing facilities.

  11. Deciphering the Hot Giant Atmospheres Orbiting Nearby Extrasolar Systems with JWST

    Science.gov (United States)

    Afrin Badhan, Mahmuda; Batalha, Natasha; Deming, Drake; Domagal-Goldman, Shawn; HEBRARD, Eric; Kopparapu, Ravi Kumar; Irwin, Patrick Gerard Joseph

    2016-10-01

    Unique and exotic planets give us an opportunity to understand how planetary systems form and evolve over their lifetime, by placing our own planetary system in the context of the vastly different extrasolar systems that are being continually discovered by present space missions. With orbital separations that are less than one-tenth of the Mercury-Sun distance, these close-in planets provide us with valuable insights about the host stellar atmosphere and planetary atmospheres subjected to their enormous stellar insolation. Observed spectroscopic signatures reveal all spectrally active species in a planet, along with information about its thermal structure and dynamics, allowing us to characterize the planet's atmosphere. NASA's upcoming missions will give us the high-resolution spectra necessary to constrain the atmospheric properties with unprecedented accuracy. However, to interpret the observed signals from exoplanetary transit events with any certainty, we need reliable atmospheric retrieval tools that can model the expected observables adequately. In my work thus far, I have built a Markov Chain Monte Carlo (MCMC) convergence scheme, with an analytical radiative equilibrium formulation for the thermal structures, within the NEMESIS atmospheric modeling tool, to allow sufficient (and efficient) exploration of the parameter space. I also augmented the opacity tables to improve the speed and reliability of retrieval models. I then utilized this upgraded version to infer the pressure-temperature (P-T) structures and volume-mixing ratios (VMRs) of major gas species in hot Jupiter dayside atmospheres, from their emission spectra. I have employed a parameterized thermal structure to retrieve plausible P-T profiles, along with altitude-invariant VMRs. Here I show my retrieval results on published datasets of HD189733b, and compare them with both medium and high spectral resolution JWST/NIRSPEC simulations. In preparation for the upcoming JWST mission, my current work

  12. Sonora: A New Generation Model Atmosphere Grid for Brown Dwarfs and Young Extrasolar Giant Planets

    Science.gov (United States)

    Marley, Mark S.; Saumon, Didier; Fortney, Jonathan J.; Morley, Caroline; Lupu, Roxana Elena; Freedman, Richard; Visscher, Channon

    2017-01-01

    Brown dwarf and giant planet atmospheric structure and composition has been studied both by forward models and, increasingly so, by retrieval methods. While indisputably informative, retrieval methods are of greatest value when judged in the context of grid model predictions. Meanwhile retrieval models can test the assumptions inherent in the forward modeling procedure. In order to provide a new, systematic survey of brown dwarf atmospheric structure, emergent spectra, and evolution, we have constructed a new grid of brown dwarf model atmospheres. We ultimately aim for our grid to span substantial ranges of atmospheric metallilcity, C/O ratios, cloud properties, atmospheric mixing, and other parameters. Spectra predicted by our modeling grid can be compared to both observations and retrieval results to aid in the interpretation and planning of future telescopic observations. We thus present Sonora, a new generation of substellar atmosphere models, appropriate for application to studies of L, T, and Y-type brown dwarfs and young extrasolar giant planets. The models describe the expected temperature-pressure profile and emergent spectra of an atmosphere in radiative-convective equilibrium for ranges of effective temperatures and gravities encompassing 200 less than or equal to T(sub eff) less than or equal to 2400 K and 2.5 less than or equal to log g less than or equal to 5.5. In our poster we briefly describe our modeling methodology, enumerate various updates since our group's previous models, and present our initial tranche of models for cloudless, solar metallicity, and solar carbon-to-oxygen ratio, chemical equilibrium atmospheres. These models will be available online and will be updated as opacities and cloud modeling methods continue to improve.

  13. Exploring Late Globalization

    DEFF Research Database (Denmark)

    Turcan, Romeo V.

    2016-01-01

    literature on late globalization from sociocultural and economic perspectives. It illustrates in a vignette the character and features of late globalization observable in the withdrawal from foreign locations or deinternationalization of universities, as late globalizing entitis. The paper discusses...

  14. Heavy flavours

    CERN Document Server

    Buras, Andrzej J

    1998-01-01

    This volume is a collection of review articles on the most outstanding topics in heavy flavour physics. All the authors have made significant contributions to this field. The book reviews in detail the theoretical structure of heavy flavour physics and confronts the Standard Model and some of its extensions with existing experimental data.This new edition covers new trends and ideas and includes the latest experimental information. Compared to the previous edition interesting new activities are included and some of the key contributions are updated. Particular attention is paid to the discover

  15. Heavy quarks

    International Nuclear Information System (INIS)

    Khoze, V.A.

    1983-10-01

    We discuss the results accumulated during the last five years in heavy quark physics and try to draw a simple general picture of the present situation. The survey is based on a unified point of view resulting from quantum chromodynamics. (orig.)

  16. Heavy ion collisions and cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Floerchinger, Stefan

    2016-12-15

    There are interesting parallels between the physics of heavy ion collisions and cosmology. Both systems are out-of-equilibrium and relativistic fluid dynamics plays an important role for their theoretical description. From a comparison one can draw interesting conclusions for both sides. For heavy ion physics it could be rewarding to attempt a theoretical description of fluid perturbations similar to cosmological perturbation theory. In the context of late time cosmology, it could be interesting to study dissipative properties such as shear and bulk viscosity and corresponding relaxation times in more detail. Knowledge and experience from heavy ion physics could help to constrain the microscopic properties of dark matter from observational knowledge of the cosmological fluid properties.

  17. Heavy metals anthropogenic pollutants in Austria

    International Nuclear Information System (INIS)

    Anderl, M.; Gager, M.; Gugele, B.; Huttunen, K.; Kurzweil, A.; Poupa, S.; Ritter, M.; Wappel, D.; Wieser, M.

    2004-01-01

    Several heavy metals from anthropogenic sources are emitted in the atmosphere damaging the air quality and the human health, besides they accumulate on the soil and lately are transmitted into the human food chain. Therefore at international level there is a concern to reduce them. Austrian heavy metals emissions (cadmium, mercury and lead) during 1990-2002 are given including an analysis of causes and sources. Lead is the main pollutant and the main sector responsible is the industry. 5 figs. (nevyjel)

  18. Thermal-orbital coupled tidal heating and habitability of Martian-sized extrasolar planets around M stars

    Energy Technology Data Exchange (ETDEWEB)

    Shoji, D.; Kurita, K. [Earthquake Research Institute, University of Tokyo, Tokyo (Japan)

    2014-07-01

    M-type stars are good targets in the search for habitable extrasolar planets. Due to their low effective temperatures, the habitable zone of M stars is very close to the stars themselves. For planets that are close to their stars, tidal heating plays an important role in thermal and orbital evolutions, especially when the planet's orbit has a relatively large eccentricity. Although tidal heating interacts with the thermal state and the orbit of the planet, such coupled calculations for extrasolar planets around M stars have not been conducted. We perform coupled calculations using simple structural and orbital models and analyze the thermal state and habitability of a terrestrial planet. Considering this planet to be Martian-sized, the tide heats up and partially melts the mantle, maintaining an equilibrium state if the mass of the star is less than 0.2 times the mass of the Sun and the initial eccentricity of the orbit is more than 0.2. The reduction of heat dissipation due to the melted mantle allows the planet to stay in the habitable zone for more than 10 Gyr even though the orbital distance is small. The surface heat flux at the equilibrium state is between that of Mars and Io. The thermal state of the planet mainly depends on the initial value of the eccentricity and the mass of the star.

  19. Thermal-orbital coupled tidal heating and habitability of Martian-sized extrasolar planets around M stars

    International Nuclear Information System (INIS)

    Shoji, D.; Kurita, K.

    2014-01-01

    M-type stars are good targets in the search for habitable extrasolar planets. Due to their low effective temperatures, the habitable zone of M stars is very close to the stars themselves. For planets that are close to their stars, tidal heating plays an important role in thermal and orbital evolutions, especially when the planet's orbit has a relatively large eccentricity. Although tidal heating interacts with the thermal state and the orbit of the planet, such coupled calculations for extrasolar planets around M stars have not been conducted. We perform coupled calculations using simple structural and orbital models and analyze the thermal state and habitability of a terrestrial planet. Considering this planet to be Martian-sized, the tide heats up and partially melts the mantle, maintaining an equilibrium state if the mass of the star is less than 0.2 times the mass of the Sun and the initial eccentricity of the orbit is more than 0.2. The reduction of heat dissipation due to the melted mantle allows the planet to stay in the habitable zone for more than 10 Gyr even though the orbital distance is small. The surface heat flux at the equilibrium state is between that of Mars and Io. The thermal state of the planet mainly depends on the initial value of the eccentricity and the mass of the star.

  20. Heavy flavours: theory summary

    OpenAIRE

    Corcella, Gennaro

    2005-01-01

    I summarize the theory talks given in the Heavy Flavours Working Group. In particular, I discuss heavy-flavour parton distribution functions, threshold resummation for heavy-quark production, progress in fragmentation functions, quarkonium production, heavy-meson hadroproduction.

  1. A search for extra-solar planetary transits in the field of open cluster NGC 6819

    Science.gov (United States)

    Street, Rachel Amanda

    The technique of searching for extra-solar planetary transits is investigated. This technique, which relies on detecting the brief, shallow eclipses caused by planets passing across the line of sight to the primary star, requires high-precision time-series photometry of large numbers of stars in order to detect these statistically rare events. Observations of 18000 stars in the field including the intermediate-age open cluster NGC 6819 are presented. This target field constrasts with the stellar environment surveyed by the radial velocity technique, which concentrates on the Solar neighbourhood. I present the data-reduction techniques used to obtain high-precision photometry in a semi-automated fashion for tens of thousands of stars at a time, together with an algorithm designed to search the resulting lightcurves for the transit signatures of hot Jupiter type planets. I describe simulations designed to test the detection efficiency of this algorithm and, for comparison, predict the number of transits expected from this data, assuming that hot Jupiter planets similar to HD 209458 are as common in the field of NGC 6819 as they are in the Solar neighbourhood. While no planetary transits have yet been identified, the detection of several very low amplitude eclipses by stellar companions demonstrates the effectiveness of the method. This study also indicates that stellar activity and particularly blending are significant causes of false detections. A useful additional consequence of studying this time-series photometry is the census it provides of some of the variable stars in the field. I report on the discovery of a variety of newly-discovered variables, including Algol-type detached eclipsing binaries which are likely to consist of M-dwarf stars. Further study of these stars is strongly recommended in order to help constrain models of stellar structure at the very low mass end. I conclude with a summary of this work in the context of other efforts being made in this

  2. On the tidal interaction of massive extrasolar planets on highly eccentric orbits

    Science.gov (United States)

    Ivanov, P. B.; Papaloizou, J. C. B.

    2004-01-01

    In this paper we develop a theory of disturbances induced by the stellar tidal field in a fully convective slowly rotating planet orbiting on a highly eccentric orbit around a central star. In this case it is appropriate to treat the tidal influence as a succession of impulsive tidal interactions occurring at periastron passage. For a fully convective planet mainly the l= 2 fundamental mode of oscillation is excited. We show that there are two contributions to the mode energy and angular momentum gain due to impulsive tidal interaction: (i) `the quasi-static' contribution, which requires dissipative processes operating in the planet, and (ii) the dynamical contribution associated with excitation of modes of oscillation. These contributions are obtained self-consistently from a single set of the governing equations. We calculate a critical `equilibrium' value of angular velocity of the planet Ωcrit determined by the condition that action of the dynamic tides does not alter the angular velocity at this rotation rate. We show that this can be much larger than the corresponding rate associated with quasi-static tides and that at this angular velocity, the rate of energy exchange is minimized. We also investigate the conditions for the stochastic increase in oscillation energy that may occur if many periastron passages are considered and dissipation is not important. We provide a simple criterion for this instability to occur. Finally, we make some simple estimates of the time-scale of evolution of the orbital semimajor axis and circularization of the initially eccentric orbit due to tides, using a realistic model of the planet and its cooling history, for orbits with periods after circularization typical of those observed for extrasolar planets Pobs>~ 3 d. Quasi-static tides are found to be ineffective for semimajor axes >~0.1 au. On the other hand, dynamic tides could have produced a very large decrease of the semimajor axis of a planet with mass of the order of the

  3. Heavy weights

    International Nuclear Information System (INIS)

    2001-01-01

    The paper mentions the important thing that it was for the country, exporting the first shipping of crude de Castilla to a company of asphalts in United States. It was not a common sale, as those that it carries out the company with the crude of Cusiana or Cano Limon. The new of this shipping is that it was the first successful test of marketing the Colombian heavy crude in the exterior, since previously it was almost considered a curse to find heavy crude by the difficulties of its transport. Today it can be taken to any refinery of the world and the best test is that, after almost a year of efforts to overcome the barriers of the transport, the company achieved its conduction from the Castilla Field, in proximities to Villavicencio, until the Covenas Port, in the Caribbean Colombian coast

  4. Heavy ions

    CERN Multimedia

    CERN. Geneva; Antinori, Federico

    2001-01-01

    Colliding two heavy nuclei at ultrarelativistic energies allows to create in the laboratory a bulk system with huge density, pressure and temperature and to study its properties. It is estimated that in Pb-Pb collisions at CERN-SPS we reach over an appreciable volume an energy density which exceeds by more than a factor 20 that of normal nuclear matter. At such densities, the hadrons are so closely packed that they interpenetrate; novel physics phenomena are expected to appear. QCD predicts that under such conditions a phase transition from a system composed of colourless hadrons to a Quark-Gluon Plasma (QGP) should occur. A rich ultrarelativistic heavy-ion physics programme is under way both at BNL-AGS and at CERN-SPS since 1986. The results obtained so far have led CERN to officially announce evidence for a new state of matter last year. A long-range programme of heavy-ion physics at higher energies is under way (BNL-RHIC) and in preparation (CERN-LHC). These lectures are meant as an introduction to the phy...

  5. Heavy ions

    CERN Multimedia

    CERN. Geneva. Audiovisual Unit

    2002-01-01

    Colliding two heavy nuclei at ultrarelativistic energies allows to create in the laboratory a bulk system with huge density, pressure and temperature and to study its properties. It is estimated that in Pb-Pb collisions at CERN-SPS we reach over an appreciable volume an energy density which exceeds by more than a factor 20 that of normal nuclear matter. At such densities, the hadrons are so closely packed that they interpenetrate; novel physics phenomena are expected to appear. QCD predicts that under such conditions a phase transition from a system composed of colourless hadrons to a Quark-Gluon Plasma (QGP) should occur. A rich ultrarelativistic heavy-ion physics programme is under way both at BNL-AGS and at CERN-SPS since 1986. The results obtained so far have led CERN to officially announce evidence for a new state of matter last year. A long-range programme of heavy-ion physics at higher energies is under way (BNL-RHIC) and in preparation (CERN-LHC). These lectures are meant as an introduction to the phy...

  6. Ultrarelativistic heavy ions

    International Nuclear Information System (INIS)

    Pugh, H.G.

    1980-12-01

    Studies with ultrarelativistic heavy ions combine aspects of cosmic ray physics, particle physics, nuclear physics, astrophysics and cosmogenesis. The leading theoretical concerns are the behavior of matter at very high-energy density and flux, the general behavior of space time in collisions, relativistic nuclear theory, and quantum chromodynamics. The field has developed over a period of more than thirty years, since the first observation of heavy nuclei in cosmic rays and the major developments of understanding of high-energy collisions made by Fermi and Landau in the early fifties. In the late sixties the discovery of the parton content of nucleons was rapidly followed by a great extension of high-energy collision phenomenology at the CERN ISR and subsequent confirmation of the QCD theory. In parallel the study of p-nucleus and nucleus-nucleus collisions at very high energies, especially at the CERN PS, Fermilab and the Bevalac, and in cosmic rays demonstrated that studies involving the nucleus opened up a new dimension in studies of the hadronic interaction. It is now at a high level of interest on an international scale, with major new accelerators being proposed to dedicate to this kind of study

  7. Heavy quark effective theory and heavy baryon transitions

    International Nuclear Information System (INIS)

    Hussain, F.

    1992-01-01

    The heavy quark effective theory (HQET) is applied to study the weak decay of heavy mesons and heavy baryons and to predict the form factors for heavy to heavy and heavy to light transitions. 28 refs, 10 figs, 2 tabs

  8. Heavy metals contamination of Chrysichthys nigrodigitatus and ...

    African Journals Online (AJOL)

    This study investigates the presence of heavy metal contamination of Chrysichthys nigrodigitatus and Lates niloticus. Adult C. nigrodigitatus and L. niloticus were obtained from fishermen in Ikere Gorge, Oyo state, Nigeria. Water samples were also collected during the wet and dry seasons of the year in the same locality.

  9. Heavy Menstrual Bleeding (Menorrhagia)

    Science.gov (United States)

    ... Us Information For… Media Policy Makers Blood Disorders Heavy Menstrual Bleeding Recommend on Facebook Tweet Share Compartir ... It can also be bleeding that is very heavy. How do you know if you have heavy ...

  10. Heavy flavour in ALICE

    CERN Document Server

    Pillot, Philippe

    2008-01-01

    Open heavy flavours and heavy quarkonium states are expected to provide essential informa- tion on the properties of the strongly interacting system fo rmed in the early stages of heavy-ion collisions at very high energy density. Such probes are espe cially promising at LHC energies where heavy quarks (both c and b) are copiously produced. The ALICE detector shall measure the production of open heavy flavours and heavy quarkonium st ates in both proton-proton and heavy-ion collisions at the LHC. The expected performances of ALICE for heavy flavour physics is discussed based on the results of simulation studies on a s election of benchmark channels

  11. Parent Stars of Extrasolar Planets - XIV. Strong Evidence of Li Abundance Deficit

    OpenAIRE

    Gonzalez, Guillermo

    2014-01-01

    We report the results of our analysis of new high resolution spectra of 30 late-F to early-G dwarf field stars for the purpose of deriving their Li abundances. They were selected from the subsample of stars in the Valenti and Fischer compilation that are lacking detected planets. These new data serve to expand our comparison sample used to test whether stars with Doppler-detected giant planets display Li abundance anomalies. Our results continue to show that Li is deficient among stars with p...

  12. Clouds in the atmospheres of extrasolar planets. V. The impact of CO2 ice clouds on the outer boundary of the habitable zone

    OpenAIRE

    Kitzmann, Daniel

    2017-01-01

    Clouds have a strong impact on the climate of planetary atmospheres. The potential scattering greenhouse effect of CO2 ice clouds in the atmospheres of terrestrial extrasolar planets is of particular interest because it might influence the position and thus the extension of the outer boundary of the classic habitable zone around main sequence stars. Here, the impact of CO2 ice clouds on the surface temperatures of terrestrial planets with CO2 dominated atmospheres, orbiting different types of...

  13. Heavy metal jako subkultura

    OpenAIRE

    KOUTNÁ, Daniela

    2016-01-01

    This bachelor thesis deals with heavy metal subculture. Its aim is to introduce the most important branches and to show broadness of heavy metal. This bachelor thesis describes development and history, briefly shows Czech heavy metal history alongside with the biggest and most popular Czech heavy metal festivals. It shows the most dressing concerns of society against this style.

  14. Personality in Late Midlife

    DEFF Research Database (Denmark)

    Mortensen, Erik Lykke; Flensborg-Madsen, Trine; Molbo, Drude

    2014-01-01

    To analyze associations in late midlife between sex, age, education and social class, and the Big Five personality traits; to analyze associations between personality traits and cognitive ability in late midlife; and to evaluate how these associations are influenced by demographic factors....

  15. Deuterium and heavy water

    International Nuclear Information System (INIS)

    Vasaru, G.; Ursu, D.; Mihaila, A.; Szentgyorgyi, P.

    1975-01-01

    This bibliography on deuterium and heavy water contains 3763 references (1932-1974) from 43 sources of information. An author index and a subject index are given. The latter contains a list of 136 subjects, arranged in 13 main topics: abundance of deuterium , catalysts, catalytic exchange, chemical equilibria, chemical kinetics, deuterium and heavy water analysis, deuterium and heavy water properties, deuterium and heavy water separation, exchange reactions, general review, heavy water as moderator, isotope effects, synthesis of deuterium compounds

  16. HEAVY-ELEMENT ENRICHMENT OF A JUPITER-MASS PROTOPLANET AS A FUNCTION OF ORBITAL LOCATION

    International Nuclear Information System (INIS)

    Helled, R.; Schubert, G.

    2009-01-01

    One possible mechanism for giant planet formation is disk instability in which the planet is formed as a result of gravitational instability in the protoplanetary disk surrounding the young star. The final composition and core mass of the planet will depend on the planet's mass, environment, and the planetesimal accretion efficiency. We calculate heavy-element enrichment in a Jupiter-mass protoplanet formed by disk instability at various radial distances from the star, considering different disk masses and surface density distributions. Although the available mass for accretion increases with radial distance (a) for disk solid surface density (σ) functions σ = σ 0 a -α with α 5 years of planetary evolution, when the planet is extended and before gap opening and type II migration take place. The accreted mass is calculated for disk masses of 0.01, 0.05, and 0.1 M sun with α = 1/2, 1, and 3/2. We show that a Jupiter-mass protoplanet can accrete 1-110 M + of heavy elements, depending on the disk properties. Due to the limitation on the accretion timescale, our results provide lower bounds on heavy-element enrichment. Our results can explain the large variation in heavy-element enrichment found in extrasolar giant planets. Since higher disk surface density is found to lead to larger heavy-element enrichment, our model results are consistent with the correlation between heavy-element enrichment and stellar metallicity. Our calculations also suggest that Jupiter could have formed at a larger radial distance than its current location while still accreting the mass of heavy elements predicted by interior models. We conclude that in the disk instability model the final composition of a giant planet is strongly determined by its formation environment. The heavy-element abundance of a giant planet does not discriminate between its origin by either disk instability or core accretion.

  17. Adaptive Annealed Importance Sampling for Multimodal Posterior Exploration and Model Selection with Application to Extrasolar Planet Detection

    Science.gov (United States)

    Liu, Bin

    2014-07-01

    We describe an algorithm that can adaptively provide mixture summaries of multimodal posterior distributions. The parameter space of the involved posteriors ranges in size from a few dimensions to dozens of dimensions. This work was motivated by an astrophysical problem called extrasolar planet (exoplanet) detection, wherein the computation of stochastic integrals that are required for Bayesian model comparison is challenging. The difficulty comes from the highly nonlinear models that lead to multimodal posterior distributions. We resort to importance sampling (IS) to estimate the integrals, and thus translate the problem to be how to find a parametric approximation of the posterior. To capture the multimodal structure in the posterior, we initialize a mixture proposal distribution and then tailor its parameters elaborately to make it resemble the posterior to the greatest extent possible. We use the effective sample size (ESS) calculated based on the IS draws to measure the degree of approximation. The bigger the ESS is, the better the proposal resembles the posterior. A difficulty within this tailoring operation lies in the adjustment of the number of mixing components in the mixture proposal. Brute force methods just preset it as a large constant, which leads to an increase in the required computational resources. We provide an iterative delete/merge/add process, which works in tandem with an expectation-maximization step to tailor such a number online. The efficiency of our proposed method is tested via both simulation studies and real exoplanet data analysis.

  18. Late-Stage Caregiving

    Science.gov (United States)

    ... Caregiving Middle-Stage Caregiving Late-Stage Caregiving Behaviors Aggression & Anger Anxiety & Agitation Depression Hallucinations Memory Loss & Confusion Repetition Sleep Issues & Sundowning Suspicion & Delusions Wandering Abuse Start Here What You Need to Know Online ...

  19. A heavy load for heavy ions

    CERN Multimedia

    2003-01-01

    On 25 September, the two large coils for the dipole magnet of ALICE, the LHC experiment dedicated to heavy ions, arrived at Point 2 on two heavy load trucks after a 1200 km journey from their assembly in Vannes, France.

  20. Ionization in atmospheres of brown dwarfs and extrasolar planets VI: Properties of large-scale discharge events

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, R. L.; Helling, Ch.; Hodosán, G.; Bilger, C.; Stark, C. R., E-mail: ch@leap2010.eu [SUPA, School of Physics and Astronomy, University of St Andrews, St Andrews KY16 9SS (United Kingdom)

    2014-03-20

    Mineral clouds in substellar atmospheres play a special role as a catalyst for a variety of charge processes. If clouds are charged, the surrounding environment becomes electrically activated, and ensembles of charged grains are electrically discharging (e.g., by lightning), which significantly influences the local chemistry creating conditions similar to those thought responsible for life in early planetary atmospheres. We note that such lightning discharges contribute also to the ionization state of the atmosphere. We apply scaling laws for electrical discharge processes from laboratory measurements and numerical experiments to DRIFT-PHOENIX model atmosphere results to model the discharge's propagation downward (as lightning) and upward (as sprites) through the atmospheric clouds. We evaluate the spatial extent and energetics of lightning discharges. The atmospheric volume affected (e.g., by increase of temperature or electron number) is larger in a brown dwarf atmosphere (10{sup 8}-10{sup 10} m{sup 3}) than in a giant gas planet (10{sup 4}-10{sup 6} m{sup 3}). Our results suggest that the total dissipated energy in one event is <10{sup 12} J for all models of initial solar metallicity. First attempts to show the influence of lightning on the local gas phase indicate an increase of small carbohydrate molecules like CH and CH{sub 2} at the expense of CO and CH{sub 4}. Dust-forming molecules are destroyed and the cloud particle properties are frozen in unless enough time is available for complete evaporation. We summarize instruments potentially suitable to observe lightning on extrasolar objects.

  1. Late onset endophthalmitis

    Directory of Open Access Journals (Sweden)

    Abdulaziz AlHadlaq

    2016-04-01

    Full Text Available We report an extremely rare presentation of late-onset endophthalmitis in a young adult patient with an unexposed Ahmed tube implant. The implant was inserted 11 years prior to presentation. There was no history of trauma or any obvious exposure on clinical examination and the tube plate was filled with purulent material. After aqueous and vitreous tap, the patient underwent intracameral, intravitreal subconjunctival antibiotic injections and was started on systemic antibiotics with good response. Endophthalmitis associated with tube drainage device can present as late as 11 years and even without an unexposed tube.

  2. Lateness to School Remediation Game

    Science.gov (United States)

    Ugwuegbulam, Charles N.; Ibrahim, Haj. Naheed

    2015-01-01

    Primary and secondary school in Nigeria encourage punctuality to school yet a good number of the learners came late to school. This is especially true in the case of day students. Learners who come late to school are usually punished in one way or the other yet the lateness to school phenomenon still persist. Lateness to school behaviour affects…

  3. Late effecten van kankerbehandeling

    NARCIS (Netherlands)

    Langeveld, Nelia E.

    2004-01-01

    In dit artikel wordt ingegaan op de lange termijn effecten van kanker op de kinderleeftijd. Vervolgens wordt een kort overzicht gegeven van de belangrijkste late gevolgen die kunnen optreden na een oncologische behandeling met radio- en/of chemotherapie toegepast in de kinderleeftijd. Er wordt kort

  4. Late-modern hipsters

    DEFF Research Database (Denmark)

    Andersen, Bjørn Schiermer

    2014-01-01

    The article deals with the cultural significance of a new figure in late-modern Western culture: the hipster. The current hipster culture, so I argue, can be used as a magnifying glass that makes impending changes to our conception of culture and of cultural development visible. It ushers...

  5. Big Java late objects

    CERN Document Server

    Horstmann, Cay S

    2012-01-01

    Big Java: Late Objects is a comprehensive introduction to Java and computer programming, which focuses on the principles of programming, software engineering, and effective learning. It is designed for a two-semester first course in programming for computer science students.

  6. Late Embryogenesis Abundant Proteins

    NARCIS (Netherlands)

    Shih, M.D.; Hoekstra, F.A.; Hsing, Y.I.C.

    2008-01-01

    During the late maturation stage of seed development, water content decreases greatly. One of the most striking characteristics of mature orthodox seeds is their ability to withstand severe desiccation. Mechanisms of plant drought/desiccation tolerance have been studied by numerous groups, and a

  7. The heavy oil refiners needs in the future

    International Nuclear Information System (INIS)

    Sauer, J.W.

    1991-01-01

    In the 1970s oil crisis, the high price differential that developed between heavy and light crude led to an expansion in heavy crude processing geared to producing light oil products. The subsequent collapse in prices meant that heavy crudes with low netbacks were shut in, heavy crude refining capacity exceeded the restrained production of heavy crudes, and refineries were operating at losses. However, the low prices for oil rekindled demand and spare production capacity has been absorbed. The crude oil price is forecast to rise to ca $27/bbl by the late 1990s, which is favorable for heavy crude oil production. Nevertheless, investments in heavy crude production are exposed to a high degree of risk. A strategy for dealing with this risk is to integrate into downstream, which makes more sense for heavy crude producers than for conventional producers. On the other hand, such integration is capital-intensive, and light oils will likely be favored in crude oil production developments for the next several years. Low prices for natural gas will make it hard to find markets for residual fuel made from heavy crudes. 8 figs

  8. Soil heavy metals

    Energy Technology Data Exchange (ETDEWEB)

    Sherameti, Irena [Jena Univ. (Germany). Inst. fuer Allgemeine Botanik und Pflanzenphysiologie; Varma, Ajit (eds.) [Amity Univ., Uttar Pradesh (India). Amity Inst. of Microbial Technology; Amity Science, Technology and Innovation Foundation, Noida, UP (India)

    2010-07-01

    Human activities have dramatically changed the composition and organisation of soils. Industrial and urban wastes, agricultural application and also mining activities resulted in an increased concentration of heavy metals in soils. How plants and soil microorganisms cope with this situation and the sophisticated techniques developed for survival in contaminated soils is discussed in this volume. The topics presented include: the general role of heavy metals in biological soil systems; the relation of inorganic and organic pollutions; heavy metal, salt tolerance and combined effects with salinity; effects on abuscular mycorrhizal and on saprophytic soil fungi; heavy metal resistance by streptomycetes; trace element determination of environmental samples; the use of microbiological communities as indicators; phytostabilization of lead polluted sites by native plants; effects of soil earthworms on removal of heavy metals and the remediation of heavy metal contaminated tropical land. (orig.)

  9. The SOPHIE search for northern extrasolar planets. X. Detection and characterization of giant planets by the dozen

    Science.gov (United States)

    Hébrard, G.; Arnold, L.; Forveille, T.; Correia, A. C. M.; Laskar, J.; Bonfils, X.; Boisse, I.; Díaz, R. F.; Hagelberg, J.; Sahlmann, J.; Santos, N. C.; Astudillo-Defru, N.; Borgniet, S.; Bouchy, F.; Bourrier, V.; Courcol, B.; Delfosse, X.; Deleuil, M.; Demangeon, O.; Ehrenreich, D.; Gregorio, J.; Jovanovic, N.; Labrevoir, O.; Lagrange, A.-M.; Lovis, C.; Lozi, J.; Moutou, C.; Montagnier, G.; Pepe, F.; Rey, J.; Santerne, A.; Ségransan, D.; Udry, S.; Vanhuysse, M.; Vigan, A.; Wilson, P. A.

    2016-04-01

    We present new radial velocity measurements of eight stars that were secured with the spectrograph SOPHIE at the 193 cm telescope of the Haute-Provence Observatory. The measurements allow detecting and characterizing new giant extrasolar planets. The host stars are dwarfs of spectral types between F5 and K0 and magnitudes of between 6.7 and 9.6; the planets have minimum masses Mp sin I of between 0.4 to 3.8 MJup and orbitalperiods of several days to several months. The data allow only single planets to be discovered around the first six stars (HD 143105, HIP 109600, HD 35759, HIP 109384, HD 220842, and HD 12484), but one of them shows the signature of an additional substellar companion in the system. The seventh star, HIP 65407, allows the discovery of two giant planets that orbit just outside the 12:5 resonance in weak mutual interaction. The last star, HD 141399, was already known to host a four-planet system; our additional data and analyses allow new constraints to be set on it. We present Keplerian orbits of all systems, together with dynamical analyses of the two multi-planet systems. HD 143105 is one of the brightest stars known to host a hot Jupiter, which could allow numerous follow-up studies to be conducted even though this is not a transiting system. The giant planets HIP 109600b, HIP 109384b, and HD 141399c are located in the habitable zone of their host star. Based on observations collected with the SOPHIE spectrograph on the 1.93-m telescope at Observatoire de Haute-Provence (CNRS), France, by the SOPHIE Consortium (programs 07A.PNP.CONS to 15A.PNP.CONS).Full version of the SOPHIE measurements (Table 1) is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/588/A145

  10. Heavy-ion targets

    International Nuclear Information System (INIS)

    Adair, H.L.; Kobisk, E.H.

    1985-01-01

    This chapter examines the characteristics of targets required in heavy-ion accelerator physics experiments. The effects of target parameters on heavy-ion experimental results are reviewed. The target fabrication and characterization techniques used to minimize experimental problems during heavy-ion bombardment are described. Topics considered include target thickness and uniformity, target lifetime, target purity, substrate materials, Doppler shift effects, metal preparations, and target preparation methods

  11. 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.

  12. Heavy quark effective theory and study of heavy hadron spectra

    International Nuclear Information System (INIS)

    Dong Yubing

    1995-01-01

    By employing the heavy quark effective theory, the spectra of heavy hadrons, such as heavy mesons (Q-barq), heavy baryons (QQq and Qqq) and heavy multiquark systems (Q-barQ-barqq) are studied systemically. The results are compared with the predictions for Q-barQ-barqq in potential model

  13. Heavy baryon transitions and the heavy quark effective theory

    International Nuclear Information System (INIS)

    Hussain, F.

    1992-01-01

    Heavy baryon decays are studied in the context of the Bethe-Salpeter approach to the heavy quark effective theory. A drastic reduction, in the number of independent form factors, is found. Results are presented both for heavy to heavy and heavy to light baryon decays. (orig.)

  14. Heavy ion physics

    International Nuclear Information System (INIS)

    Kalpakchieva, R.; Cherepanov, E.A.

    1993-01-01

    The international school-seminar on heavy ion physics had been organized in Dubna in may of 1993. The scientific program of reports covers the following main topics: synthesis and properties of heavy nuclei; synthesis and investigation of properties of exotic nuclei; experiments with radioactive nuclear beams; interaction between complex nuclei at low and intermediate energies. It also includes reports on laser spectroscopy and exotic nuclear beams, on some application of heavy ion beams for the problems of solid state physics, on construction of multidetector facilities and on developing of heavy ion accelerator complexes. Short communication

  15. Heavy-ion radiography

    International Nuclear Information System (INIS)

    Fabrikant, J.I.; Tobias, C.A.; Holley, W.R.; Benton, E.V.; Woodruff, K.H.; MacFarland, E.W.

    1983-01-01

    High energy, heavy-ion beams offer superior discrimination of tissue electron densities at very low radiation doses. This characteristic has potential for diagnostic medical imaging of neoplasms arising in the soft tissues and organs because it can detect smaller inhomogeneities than x rays. Heavy-ion imaging may also increase the accuracy of cancer radiotherapy planning involving use of accelerated charged particles. In the current physics research program of passive heavy-ion imaging, critical modulation transfer function tests are being carried out in heavy-ion projection radiography and heavy-ion computerized tomography. The research goal is to improve the heavy-ion imaging method until it reaches the limits of its theoretical resolution defined by range straggling, multiple scattering, and other factors involved in the beam quality characteristics. Clinical uses of the imaging method include the application of heavy-ion computerized tomography to heavy-ion radiotherapy planning, to the study of brain tumors and other structures of the head, and to low-dose heavy-ion projection mammography, particularly for women with dense breasts where other methods of diagnosis fail. The ions used are primarily 300 to 570 MeV/amu carbon and neon ions accelerated at the Lawrence Berkeley Laboratory Bevalac

  16. Production of heavy water

    Science.gov (United States)

    Spencer, Larry S.; Brown, Sam W.; Phillips, Michael R.

    2017-06-06

    Disclosed are methods and apparatuses for producing heavy water. In one embodiment, a catalyst is treated with high purity air or a mixture of gaseous nitrogen and oxygen with gaseous deuterium all together flowing over the catalyst to produce the heavy water. In an alternate embodiment, the deuterium is combusted to form the heavy water. In an alternate embodiment, gaseous deuterium and gaseous oxygen is flowed into a fuel cell to produce the heavy water. In various embodiments, the deuterium may be produced by a thermal decomposition and distillation process that involves heating solid lithium deuteride to form liquid lithium deuteride and then extracting the gaseous deuterium from the liquid lithium deuteride.

  17. Late-Onset Asthma

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli

    2017-01-01

    Late-onset asthma is common, associated with poor outcome, underdiagnosed and undertreated, possibly due to the modifying effect of ageing on disease expression. Although the diagnostic work-up in elderly individuals suspected of having asthma follows the same steps as in younger individuals (case......, to objectively confirm asthma. If necessary, a trial of oral or inhaled corticosteroid might be necessary. Asthma can be diagnosed when increased airflow variability is identified in a symptomatic patient, and if the patient does not have a history of exposure, primarily smoking, known to cause chronic...... obstructive pulmonary disease, the diagnosis is asthma even if the patient does not have fully reversible airflow obstruction. Pharmacological therapy in patients with late-onset asthma follows international guidelines, including treatment with the lowest effective dose of inhaled corticosteroid to minimize...

  18. Accelerated pavement testing efforts using the heavy vehicle simulator

    CSIR Research Space (South Africa)

    Du Plessis, Louw

    2017-10-01

    Full Text Available This paper provides a brief description of the technological developments involved in the development and use of the Heavy Vehicle Simulator (HVS) accelerated pavement testing equipment. This covers the period from concept in the late 1960’s...

  19. Late Babylonian Astrology

    Science.gov (United States)

    Steele, John M.

    The last five centuries BC saw the development of several new forms of astrology in Babylonia. Key to these new astrological techniques was the invention of the zodiac in about 400 BC. These new forms of astrology include personal horoscopes, astral medicine, and the exploitation of geometrical relationships between the position of heavenly bodies. Several Late Babylonian astrological doctrines were later adopted within Greek astrology.

  20. Late Palaeozoic plants.

    Science.gov (United States)

    Feng, Zhuo

    2017-09-11

    Land plants are one of the major constituents of terrestrial ecosystems on Earth, and play an irreplaceable role in human activities today. If we are to understand the extant plants, it is imperative that we have some understanding of the fossil plants from the deep geological past, particularly those that occurred during their early evolutionary history, in the late Palaeozoic. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Late somatic effects

    International Nuclear Information System (INIS)

    Gilbert, E.S.

    1989-01-01

    Late effects are by definition effects that occur at least one year, and in most cases decades, after the time of exposure. The late effects considered in this chapter are limited to latent cancer incidence and mortality, and benign thyroid disease. A model is provided for estimating risks of late effects resulting from the radiation exposure likely to be received in the event of a nuclear power plant accident. It is assumed that exposure to high-LET radiation would be negligible in such an accident, and thus only risks from low-LET exposure are evaluated. Separate estimates are provided for risks of leukemia, bone cancer, lung cancer, gastrointestinal cancers, thyroid cancer, skin cancer, and the residual group of all other cancers; estimates of leukemia and other cancers due to in utero exposure are also provided. Risks are expressed in absolute terms as the number of cancer deaths (or cases) per million persons exposed to a particular dose. Because the time of death is also important in assessing the impact of an accident, and because the quality of life after the occurrence of cancer will often be reduced, the number of years of life lost and the number of years of life lived after the occurrence of cancer are also estimated

  2. Coping – Late Side Effects

    Science.gov (United States)

    Cancer treatment can cause late side effects that may not show up for months or years after treatment. These late effects may include heart and lung problems, bone loss, eye and hearing changes, lymphedema, and other problems

  3. Heavy-Quark Production

    CERN Document Server

    Frixione, Stefano; Nason, Paolo; Ridolfi, Giovanni

    1997-01-01

    We review the present theoretical and experimental status of heavy quark production in high-energy collisions. In particular, we cover hadro- and photoproduction at fixed target experiments, at HERA and at the hadron colliders, as well as aspects of heavy quark production in e+e- collisions at the Z0 peak.

  4. Canadian heavy water production

    International Nuclear Information System (INIS)

    Dahlinger, A.; Lockerby, W.E.; Rae, H.K.

    1977-05-01

    The paper reviews Canadian experience in the production of heavy water, presents a long-term supply projection, relates this projection to the anticipated long-term electrical energy demand, and highlights principal areas for further improvement that form the bulk of our research and development program on heavy water processes

  5. Heavy ion fusion

    International Nuclear Information System (INIS)

    Bangerter, R.O.

    1986-01-01

    This report on the International Symposium on Heavy Ion Fusion held May 27-29, 1986 summarizes the problems and achievements in the areas of targets, accelerators, focussing, reactor studies, and system studies. The symposium participants recognize that there are large uncertainties in Heavy Ion Fusion but many of them are also optimistic that HIF may ultimately be the best approach to fusion

  6. Heavy water and nonproliferation

    International Nuclear Information System (INIS)

    Miller, M.M.

    1980-05-01

    This report begins with a historical sketch of heavy water. The report next assesses the nonproliferation implications of the use of heavy water-moderated power reactors; several different reactor types are discussed, but the focus is on the natural uranium, on-power fueled, pressure tube reactor CANDU. The need for and development of on-power fueling safeguards is discussed. Also considered is the use of heavy water in plutonium production reactors as well as the broader issue of the relative nuclear leverage that suppliers can bring to bear on countries with natural uranium-fueled reactors as compared to those using enriched designs. The final chapter reviews heavy water production methods and analyzes the difficulties involved in implementing these on both a large and a small scale. It concludes with an overview of proprietary and nonproliferation constraints on heavy water technology transfer

  7. Late induced abortion.

    Science.gov (United States)

    Savage, W

    1990-09-01

    In the UK in 1988, 13.3% of abortions were performed at 13 weeks' gestation or later. Reasons for this delay, in addition to the diagnosis through amniocentesis of a fetal abnormality, include late recognition of pregnancy, a change of mind about completing the pregnancy, a failure of primary care physicians to entertain the diagnosis of pregnancy, travel or financial problems, and referral difficulties and scheduling delays. Women with little education and very young women are most likely to present for late abortions. From 13-16 weeks, dilatation and evacuation is the safest method of pregnancy termination. The procedure can be made easier through preparation of the cervix with a prostaglandin pessary or Foley catheter. After 16 weeks, an instillation method is recommended; prostaglandin administration can be intro- or extra-amniotic. Complication rates at 13-19 weeks are 14.5/1000 for vaginal methods of abortion and 7.2/1000 for prostaglandin methods. The risk of complications is 3 times higher for women who have 2nd-trimester abortions through the National Health Service. Although it is not realistic to expect that late abortions ever can be eliminated, improved sex education and contraceptive reliability as well as reforms in the National Health Service could reduce the number substantially. To reduce delay, it is suggested that the National Health Service set up satellite day care units and 1-2 central units in each region to deal quickly with midtrimester abortions. Delays would be further reduced by legislation to allow abortion on request in at least the 1st trimester of pregnancy.

  8. Late Washing efficiency

    International Nuclear Information System (INIS)

    Morrissey, M.F.

    1992-01-01

    Interim Waste Technology has demonstrated the Late Washing concept on the Experimental Laboratory Filter (ELF) at TNX. In two tests, washing reduced the [NO 2 - ] from 0.08 M to approximately 0.01 M on slurries with 2 year equivalent radiation exposures and 9.5 wt. % solids. For both washes, the [NO 2 - ] decreased at rates near theoretical for a constant volume stirred vessel, indicating approximately l00% washing efficiency. Permeate flux was greater than 0.05 gpm/ft 2 for both washes at a transmembrane pressure of 50 psi and flow velocity of 9 ft/sec

  9. Late-onset hypogonadism

    Directory of Open Access Journals (Sweden)

    Piotr Dudek

    2017-06-01

    Full Text Available In Poland, the number of men over the age of 50 years exceeds 6 million. It is estimated that about 2-6% of this population develops symptoms of late-onset hypogonadism (LOH. In men, testosterone deficiency increases slightly with age. LOH is a clinically and biochemically defined disease of older men with serum testosterone level below the reference parameters of younger healthy men and with symptoms of testosterone deficiency, manifested by pronounced disturbances of quality of life and harmful effects on multiple organ systems. Testosterone replacement therapy may give several benefits regarding body composition, metabolic control, and psychological and sexual parameters.

  10. Early and late motherhood

    DEFF Research Database (Denmark)

    Christoffersen, Mogens; Lausten, Mette

    2009-01-01

    The study investigates parental child rearing methods, structural factors relating to the family during adolescence geographic segregation, individual resource deficits and social background of first time late live births among 32 to 37 years old women and compare to teenagers before becoming...... economic and social gradient for first-time teenage mothers. Teenagers who had experienced family separation or who were formerly in out-of-home care in particular had an increased risk of early childbearing. Results showed that teenage mothers were in every respect in a more disadvantaged position than...

  11. Heavy-ion dosimetry

    International Nuclear Information System (INIS)

    Schimmerling, W.

    1980-03-01

    This lecture deals with some of the more important physical characteristics of relativistic heavy ions and their measurement, with beam delivery and beam monitoring, and with conventional radiation dosimetry as used in the operation of the BEVALAC biomedical facility for high energy heavy ions (Lyman and Howard, 1977; BEVALAC, 1977). Even so, many fundamental aspects of the interaction of relativistic heavy ions with matter, including important atomic physics and radiation chemical considerations, are not discussed beyond the reminder that such additional understanding is required before an adequte perspective of the problem can be attained

  12. Phenomenology of heavy leptons and heavy quarks

    International Nuclear Information System (INIS)

    Gilman, F.J.

    1978-11-01

    The review of the quark and lepton family includes properties of the tau, SU(2) x U(1) classification of the tau and its decays, heavier leptons, the spectroscopy of heavy hadrons composed of quarks, their strong and electromagnetic decays, the weak interaction properties of the c, b, and t quarks, and the decays of hadrons containing them expected within the context of the standard SU(2) x U(1) model. 76 references

  13. Heavy Flavour Production

    CERN Document Server

    Nason, Paolo; Ridolfi, Giovanni

    1995-01-01

    We review the status of heavy flavour production in QCD. Comparison of experimental and theoretical results for top and bottom production are given. Selected topics in charm production are also discussed.

  14. Heavy element research

    International Nuclear Information System (INIS)

    Anon.

    1976-01-01

    Heavy element research activities in metallurgy and ceramics during 1976 at Lawrence Berkeley Laboratory are reviewed. Topics include: microstructure, properties and alloy design; ceramic alloy program; high resolution and high voltage electron microscopy; and powder metallurgy

  15. Heavy rain effects

    Science.gov (United States)

    Dunham, R. Earl, Jr.

    1994-01-01

    This paper summarizes the current state of knowledge of the effect of heavy rain on airplane performance. Although the effects of heavy rain on airplane systems and engines are generally known, only recently has the potential aerodynamic effect of heavy rain been recognized. In 1977 the United States Federal Aviation Administration (FAA) conducted a study of 25 aircraft accidents and incidents which occurred between 1964 and 1976 in which low-altitude wind shear could have been a contributing factor. Of the 25 cases (23 approach or landing and 2 take-off) in the study, ten cases had occurred in a rain environment, and in five cases these were classified as intense or heavy rain encounters. These results led to the reconsideration of high-intensity, short-duration rainfall as a potential weather-related aircraft safety hazard, particularly in the take-off and/or approach phases of flight.

  16. Late-Modern Symbolism

    DEFF Research Database (Denmark)

    Andersen, Bjørn Schiermer

    2015-01-01

    Through analysis of key texts, I seek to demonstrate the explanative potential of Durkheim’s sociology of religion in the present context. I critically readdress the idea, found in his early work, that modernity is characterized by a rupture with pre-modern forms of solidarity. First, I investigate...... the ways in which Durkheim sets up a stark distinction between the pre-modern and the modern in his early work, and how this distinction is further cemented by his orthodox critique of the modern economy and its negative effects on social life. Second, I show how another timeless and positive understanding...... of “mechanical” solidarity is to be found behind the “symbolist” template crystalizing in Durkheim’s late work. Third, I develop this template for a modern context by critically addressing and removing other obstacles and prejudices on Durkheim’s part....

  17. Late somatic effects

    International Nuclear Information System (INIS)

    Gilbert, E.

    1985-01-01

    A model is provided for estimating risks of late effects resulting from low-LET radiation exposure likely to be received in the event of a nuclear power plant accident. Separate estimates are provided for risks of leukemia, cancers of the bones, lungs, gastrointestinal tract, thyroid, skin, and the residual group of all other cancers; estimates of leukemia and other cancers due to in utero exposure are also provided. Risks are expressed in absolute terms as the number of cancer deaths (or cases) per million persons exposed to a particular dose. In addition, the number of years of life lost and the number of years of life lived after the occurrence of cancer are also estimated. The model used in the earlier Reactor Safety Study has been modified to reflect additional epidemiological data and these changes are described in detail. 37 references, 1 figure, 13 tables

  18. Heavy ion accelerators

    International Nuclear Information System (INIS)

    Schmelzer, C.

    1974-01-01

    This review of the present state of work on heavy-ion accelerators pays particular attention to the requirements for nuclear research. It is divided into the following sections: single-particle versus collective acceleration, heavy-ion accelerators, beam quality, and a status report on the UNILAC facility. Among the topics considered are the recycling cyclotron, linacs with superconducting resonators, and acceleration to the GeV/nucleon range. (8 figures, 2 tables) (U.S.)

  19. Ecological risk and pollution history of heavy metals in Nansha mangrove, South China.

    Science.gov (United States)

    Wu, Qihang; Tam, Nora F Y; Leung, Jonathan Y S; Zhou, Xizhen; Fu, Jie; Yao, Bo; Huang, Xuexia; Xia, Lihua

    2014-06-01

    Owing to the Industrial Revolution in the late 1970s, heavy metal pollution has been regarded as a serious threat to mangrove ecosystems in the region of the Pearl River Estuary, potentially affecting human health. The present study attempted to characterize the ecological risk of heavy metals (Cd, Cr, Cu, Mn, Ni, Pb and Zn) in Nansha mangrove, South China, by estimating their concentrations in the surface sediment. In addition, the pollution history of heavy metals was examined by determining the concentrations of heavy metals along the depth gradient. The phytoremediation potential of heavy metals by the dominant plants in Nansha mangrove, namely Sonneratia apetala and Cyperus malaccensis, was also studied. Results found that the surface sediment was severely contaminated with heavy metals, probably due to the discharge of industrial sewage into the Pearl River Estuary. Spatial variation of heavy metals was generally unobvious. The ecological risk of heavy metals was very high, largely due to Cd contamination. All heavy metals, except Mn, decreased with depth, indicating that heavy metal pollution has been deteriorating since 1979. Worse still, the dominant plants in Nansha mangrove had limited capability to remove the heavy metals from sediment. Therefore, we propose that immediate actions, such as regulation of discharge standards of industrial sewage, should be taken by the authorities concerned to mitigate the ecological risk posed by heavy metals. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Heavy oils clean up

    International Nuclear Information System (INIS)

    Collitt, R.

    1997-01-01

    High production, transport and refining costs have long led oil companies to shun heavy crude oils. Advances in the technology of upgrading heavy oils, however, are likely to reduce transport costs and improve the refinery output. Research and development by Venezuela's state oil company, Petroleos de Venezuela (PDVSA), has resulted in a process called Aquaconversion which permits the upgrading of heavy crude oils using a catalyst and the hydrogen from steam. This may be carried out at the wellhead in small low-pressure and relatively inexpensive units. In addition, higher distillate yields of higher value could be produced by revamping the thermal cracking units of refineries to incorporate the new technology. This has generated considerable interest in Venezuela's large extra-heavy crude oil reserves and has led multinational oil companies along with PDVSA to pledge $17 billion to their development. Even at a $2 to $3 per barrel upgrading cost, Venezuela's extra heavy crudes are competitive with lighter oils from other countries. Other major markets for the new technology are likely to be China and Russia, given their own large heavy crude reserves. (UK)

  1. Process for removing heavy metal compounds from heavy crude oil

    Science.gov (United States)

    Cha, Chang Y.; Boysen, John E.; Branthaver, Jan F.

    1991-01-01

    A process is provided for removing heavy metal compounds from heavy crude oil by mixing the heavy crude oil with tar sand; preheating the mixture to a temperature of about 650.degree. F.; heating said mixture to up to 800.degree. F.; and separating tar sand from the light oils formed during said heating. The heavy metals removed from the heavy oils can be recovered from the spent sand for other uses.

  2. Late Carboniferous to Late Permian carbon isotope stratigraphy

    DEFF Research Database (Denmark)

    Buggisch, Werner; Krainer, Karl; Schaffhauser, Maria

    2015-01-01

    An integrated study of the litho-, bio-, and isotope stratigraphy of carbonates in the Southern Alps was undertaken in order to better constrain δ13C variations during the Late Carboniferous to Late Permian. The presented high resolution isotope curves are based on 1299 δ13Ccarb and 396 δ13Corg...

  3. Heavy Metal Stars

    Science.gov (United States)

    2001-08-01

    atomic mass and hence, increasing positive charge of the nuclei, the electric repulsion between the nuclei becomes stronger and stronger. In fact, the fusion process only works up to a certain mass limit, corresponding to the element Iron [2]. All elements that are heavier than Iron cannot be produced via this path. But then, how were those heavy elements we now find on the Earth produced in the first place? From where comes the Zirconium in artificial diamonds, the Barium that colours fireworks, the Tungsten in the filaments in electric bulbs? Which process made the Lead in your car battery? Beyond iron The production of elements heavier than Iron takes place by adding neutrons to the atomic nuclei . These neutral particles do not feel any electrical repulsion from the charged nuclei. They can therefore easily approach them and thereby create heavier nuclei. This is indeed the way the heaviest chemical elements are built up. There are actually two different stellar environments where this process of "neutron capture" can happen. One place where this process occurs is inside very massive stars when they explode as supernovae . In such a dramatic event, the build-up proceeds very rapidly, via the so-called "r-process" ( "r" for rapid ). The AGB stars But not all heavy elements are created in such an explosive way. A second possibility follows a more "peaceful" road. It takes place in rather normal stars, when they burn their Helium towards the end of their lives. In the so-called "s-process" ( "s" for slow ), heavier elements are then produced by a rather gentle addition of neutral neutrons to atomic nuclei. In fact, roughly half of all the elements heavier than Iron are believed to be synthesized by this process during the late evolutionary phases of stars. This process takes place during a specific stage of stellar evolution, known as the "AGB" phase [3]. It occurs just before an old star expels its gaseous envelope into the surrounding interstellar space and sometime

  4. The late administration of surfactant

    African Journals Online (AJOL)

    HMD and 4 as having congenital pneumonia. Overall there was a significant and sustained improvement ... 3 infants weighing> 2 400 g with congenital pneumonia responded to a single delayed dose of SRT. Late SRT is ..... pneumonia and meconium aspiration syndrome.' It does not appear that late SRT compromised the ...

  5. Heavy-ion radiography

    International Nuclear Information System (INIS)

    Fabrikant, J.I.; Tobias, C.A.; Holley, W.R.; Benton, E.V.

    1981-01-01

    Heavy-particle radiography has clinical potential as a newly developed noninvasive low-dose imaging procedure that provides increased resolution of minute density differences in soft tissues of the body. The method utilizes accelerated high-energy ions, primarily carbon and neon, at the Bevalac accelerator at the Lawrence Berkeley Laboratory. The research program for medicine utilizes heavy-ion radiography for low-dose mammography, for treatment planning for cancer patients, and for imaging and accurate densitometry of skeletal structures, brain and spinal neoplasms, and the heart. The potential of heavy-ion imaging, and particularly reconstruction tomography, is now proving to be an adjunct to existing diagnostic imaging procedures in medicine, both for applications to the diagnosis, management and treatment of clinical cancer in man, and for the early detection of small soft-tissue tumors at low radiation dose

  6. Very heavy dark Skyrmions

    International Nuclear Information System (INIS)

    Dick, Rainer

    2017-01-01

    A dark sector with a solitonic component provides a means to circumvent the problem of generically low annihilation cross sections of very heavy dark matter particles. At the same time, enhanced annihilation cross sections are necessary for indirect detection of very heavy dark matter components beyond 100 TeV. Non-thermally produced dark matter in this mass range could therefore contribute to the cosmic γ-ray and neutrino flux above 100 TeV, and massive Skyrmions provide an interesting framework for the discussion of these scenarios. Therefore a Higgs portal and a neutrino portal for very heavy Skyrmion dark matter are discussed. The Higgs portal model demonstrates a dark mediator bottleneck, where limitations on particle annihilation cross sections will prevent a signal from the potentially large soliton annihilation cross sections. This problem can be avoided in models where the dark mediator decays. This is illustrated by the neutrino portal for Skyrmion dark matter. (orig.)

  7. Heavy-Load Lifting

    DEFF Research Database (Denmark)

    Bloomquist, Kira; Oturai, Peter; Steele, Megan L

    2018-01-01

    of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal....... repetition maximum (RM), two sets of 15-20 repetitions) and heavy-load (85-90% 1RM, three sets of 5-8 repetition) upper-extremity resistance exercise separated by a one-week wash-out period. Swelling was determined by bioimpedance spectroscopy and dual energy x-ray absorptiometry, with breast cancer......-related lymphedema symptoms (heaviness, swelling, pain, tightness) reported using a numeric rating scale (0-10). Order of low- versus heavy-load was randomized. All outcomes were assessed pre-, immediately post-, and 24- and 72-hours post-exercise. Generalized estimating equations were used to evaluate changes over...

  8. Very heavy dark Skyrmions

    Energy Technology Data Exchange (ETDEWEB)

    Dick, Rainer [University of Saskatchewan, Department of Physics and Engineering Physics, Saskatoon, SK (Canada)

    2017-12-15

    A dark sector with a solitonic component provides a means to circumvent the problem of generically low annihilation cross sections of very heavy dark matter particles. At the same time, enhanced annihilation cross sections are necessary for indirect detection of very heavy dark matter components beyond 100 TeV. Non-thermally produced dark matter in this mass range could therefore contribute to the cosmic γ-ray and neutrino flux above 100 TeV, and massive Skyrmions provide an interesting framework for the discussion of these scenarios. Therefore a Higgs portal and a neutrino portal for very heavy Skyrmion dark matter are discussed. The Higgs portal model demonstrates a dark mediator bottleneck, where limitations on particle annihilation cross sections will prevent a signal from the potentially large soliton annihilation cross sections. This problem can be avoided in models where the dark mediator decays. This is illustrated by the neutrino portal for Skyrmion dark matter. (orig.)

  9. Heavy fermion materials

    International Nuclear Information System (INIS)

    Smith, J.L.; Cooke, D.W.

    1986-01-01

    The heavy-fermion ground state occurs in a few select metallic compounds as a result of interactions between f-electron and conduction-electron spins. A characteristically large electronic heat capacity at low temperature indicates that the effective electron mass of these materials is more than two orders of magnitude greater than that expected for a free-electron metal. This heavy-fermion ground state can become superconducting or antiferromagnetic, exhibiting very unusual properties. These materials and the role of muon spin rotation in their study are briefly discussed

  10. [Relativistic heavy ion research

    International Nuclear Information System (INIS)

    1990-01-01

    At Brookhaven National Laboratory, participation in the E802 Experiment, which is the first major heavy-ion experiment at the BNL-AGS, was the main focus of the group during the past four years. The emphases of the E802 experiment were on (a) accurate particle identification and measurements of spectra over a wide kinematical domain (5 degree LAB < 55 degree, p < 20 GeV/c); and (b) measurements of small-angle two-particle correlations, with event characterization tools: multiplicity array, forward and large-angle calorimeters. This experiment and other heavy ion collision experiments are discussed in this report

  11. Search for heavy particles

    International Nuclear Information System (INIS)

    Barnett, R.M.

    1977-03-01

    Direct and indirect evidence for the existence of a new heavy quark b and of new heavy neutral leptons N/sub e/ and N/sub μ/ can be sought in neutrino and e + e - scattering. These particles are expected to have right-handed currents. Discussion is given on the characteristics, production and decay of hadrons such as bb, ub and db, and of the massive neutral leptons. Muon number violation with and without N/sub e/ and N/sub μ/ is considered

  12. Heavy ion collisions

    International Nuclear Information System (INIS)

    Jacak, B.V.

    1994-01-01

    Heavy ion collisions at very high energies provide an opportunity to recreate in the laboratory the conditions which existed very early in the universe, just after the big bang. We prepare matter at very high energy density and search for evidence that the quarks and gluons are deconfined. I describe the kinds of observables that are experimentally accessible to characterize the system and to search for evidence of new physics. A wealth of information is now available from CERN and BNL heavy ion experiments. I discuss recent results on two particle correlations, strangeness production, and dilepton and direct photon distributions

  13. Evidences of climatic variations during Late Pleistocene- Holocene in the eastern Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Chauhan, O.S; Borole, D.V.; Gujar, A; Mascarenhas, A; Mislankar, P.G.; Rao, Ch.M.

    Based upon the variations of clay minerals, sediment texture, heavy mineral assemblage and sup(230)Th excess in the Late Pleistocene sediments of a hemipelagic core from the eastern Bay of Bengal (2713 m water depth), 35 cm and 73-78 cm levels...

  14. Heavy baryons in the heavy quark effective theory

    International Nuclear Information System (INIS)

    Koerner, J.G.; Thompson, G.

    1991-10-01

    We give a mini-review of recent results on current-induced transitions between heavy baryons (and between heavy and light baryons) in the light of the new spin and flavour symmetries of the Heavy Quark Effective Theory (HQET). We discuss the structure of the 1/m corrections to the heavy mass limit and outline a diagrammatic proof that there are no 0(1/m) correction to the Voloshin-Shifman normalization condition at zero recoil. (orig.)

  15. Heavy ion accelerator GANIL

    International Nuclear Information System (INIS)

    1975-04-01

    This article presents GANIL, a large national heavy ion accelerator. The broad problems of nuclear physics, atomic physics, astrophysics and physics of condensed media which can be approached and studied with this machine are discussed first, after which the final construction project is described. The project comprises a circular injector, a separated sector cyclotron up beam stripper, and a second separated cyclotron downstream [fr

  16. Heavy liquid bubble chamber

    CERN Multimedia

    CERN PhotoLab

    1965-01-01

    The CERN Heavy liquid bubble chamber being installed in the north experimental hall at the PS. On the left, the 1180 litre body; in the centre the magnet, which can produce a field of 26 800 gauss; on the right the expansion mechanism.

  17. Heavy quarks photoproduction

    International Nuclear Information System (INIS)

    Cacciari, M.

    1996-08-01

    The state of the art of the theoretical calculations for heavy quarks photoproduction is reviewed. The full next-to-leading order calculation and two possible resummations, the high energy one for total cross sections and the large p T one for differential cross sections, are described. (orig.)

  18. Bioaccumulation of Heavy Metals

    African Journals Online (AJOL)

    komla

    acute toxicity and sublethal chronic action the devastating effects that the accumulation - including ... the laboratory and kept in holding glass (a) Copper as CuSO,.5H,0 ... from 2 psu to 21 psu) depending on time of The choice of heavy metals for this s year. ... serving as substrate and food source for Salinity of test media.

  19. Heavy-ion microscopy

    International Nuclear Information System (INIS)

    Kraft, G.; Yang, T.C.H.; Richards, T.; Tobias, C.A.

    1980-01-01

    This chapter briefly describes the techniques of optical microscopy, scanning and transmission electron microscopy, soft x-ray microscopy and compares these latter techniques with heavy-ion microscopy. The resolution obtained with these various types of microscopy are compared and the influence of the etching procedure on total resolution is discussed. Several micrographs of mammalian cells are included

  20. Heavy chain only antibodies

    DEFF Research Database (Denmark)

    Moghimi, Seyed Moein; Rahbarizadeh, Fatemeh; Ahmadvand, Davoud

    2013-01-01

    Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen...

  1. Relativisitic heavy ion collisions

    International Nuclear Information System (INIS)

    Tannenbaum, M.J.

    1987-01-01

    Some of the objectives and observables of Relativistic Heavy Ion Physics are presented. The first experimental results from oxygen interactions at CERN, 200 GeV/c per nucleon, and BNL, 14.5 GeV/c per nucleon are shown. The data indicate more energy emission than was originally predicted. 25 refs., 19 figs

  2. Heavy-ion radiography and heavy-ion computed tomography

    International Nuclear Information System (INIS)

    Fabrikant, J.I.; Holley, W.R.; McFarland, E.W.; Tobias, C.a.

    1982-02-01

    Heavy-ion projection and CT radiography is being developed into a safe, low-dose, noninvasive radiological procedure that can quantitate and image small density differences in human tissues. The applications to heavy-ion mammography and heavy-ion CT imaging of the brain in clinical patients suggest their potential value in cancer diagnosis

  3. 7 CFR 920.112 - Late payments.

    Science.gov (United States)

    2010-01-01

    ... Miscellaneous Provisions § 920.112 Late payments. Pursuant to § 920.41(a), interest will be charged at a 1.5 percent monthly simple interest rate. Assessments for kiwifruit shall be deemed late if not received... late charge will be assessed when payment becomes 30 days late. Interest and late payment charges shall...

  4. Heavy quarks - experimental

    International Nuclear Information System (INIS)

    Hollebeek, R.

    1990-01-01

    The purpose of these lectures, given at the 1989 SLAC Summer School, was to discuss the experimental aspects of heavy quark production. A companion set of lectures on the theoretical point of view were to be given by Keith Ellis. An experimentalist should gather together the measurements which have been made by various groups, compare, contrast and tabulate them, and if possible point out the ways in which these measurements confirm or contradict current theories. Here the authors has tried to do this, although the reader who expects to find here the latest of all experimental measurements should probably be forewarned that the field is moving extremely rapidly. In some cases, he has added and updated materials where crucial new information became available after or during the summer of 1989, but not in all cases. He has concentrated on trying to select those measurements which are at the moment most crucial in refining our understanding of heavy quarks as opposed to those which merely measure things which are perhaps too complicated to be enlightening at the moment. While theorists worry primarily about production mechanisms, cross sections, QCD corrections, and to some extent about signatures, the experimentalist must determine which measurements he is interested in making, and which signatures for heavy quark production are realistic and likely to produce results which will shed some new light on the underlying production model without undo theoretical complications. Experimentalists also need to evaluate the available experimental equipment, both machines and detectors to find the best way to investigate the properties of heavy quarks. In many cases, the things which we would like to measure are severely restricted by what we can measure. Nevertheless, many properties of heavy quark production and decay can be measured, and the results have already taught us much about the weak interactions and QCD

  5. Heavy water at Aswan

    International Nuclear Information System (INIS)

    1959-01-01

    A fertilizer factory is being built by Egyptian Chemical Industries (Kima) at Aswan on the upper Nile; it will produce a mixture of ammonium nitrate and calcium carbonate adjusted to contain 20.5% nitrogen. It is also proposed to construct a heavy water plant to be located at and integrated with the fertilizer factory. At the request of the Government of the United Arab Republic, the International Atomic Energy Agency sent an expert to carry out investigation of the technical, economic and other related aspects of the proposed production of heavy water. A report was submitted to the IAEA Director General. Its main conclusions can be summarized as follows: (1) Production of heavy water as a by-product of fertilizer manufacture at Aswan is technically feasible. Separation of deuterium from industrial hydrogen for this purpose could be done either by catalytic exchange or by liquefaction and distillation; the choice should depend on economic considerations. (2) The heavy water produced at Aswan should be competitive in cost with that produced elsewhere; this, however, would depend on whether firm contracts are obtained for the delivery of equipment at guaranteed prices and with guaranteed performance, and whether such prices are in reasonable agreement with preliminary estimates. (3) The future market for heavy water is difficult to predict. For one thing, there is a very large production capacity in the USA, most of which is idle due to lack of demand. Secondly, there is a relatively small production outside the USA that is sold at prices higher than that charged by the US Government. The future of the market is necessarily contingent upon the possibility of future free sale by the US Government. At the end of his report, the expert has also given his comments on possible further assistance to the project by IAEA

  6. Heavy Flavour Production at HERA

    International Nuclear Information System (INIS)

    Bailey, D.

    2001-01-01

    ZEUS and H1 results on heavy quark production using the HERA data from 1995 to 2000 are summarised with emphasis on unresolved problems. The HERA upgrade and its impact on future heavy flavour measurements is briefly discussed

  7. (17) ACCUMULATION OF HEAVY METAL

    African Journals Online (AJOL)

    Adeyinka Odunsi

    Spectrophotometer (AAS) 2ID using their respective lamp and wavelengths. Calculation ... (Table 2). Concentration of heavy metals in the cassava. Lead and chromium were not significantly ..... Market basket survey for some heavy metals in ...

  8. Heavy mineral analyses as a powerful tool in fluvial geomorphology

    Science.gov (United States)

    von Suchodoletz, Hans; Gärtner, Andreas; Faust, Dominik

    2014-05-01

    The Marneuli depression is a tectonic sub-basin of the Transcaucasian depression in eastern Georgia, filled with several decametres of fluvial, lacustrine and aeolian Quaternary sediments. In order to reconstruct past landscape evolution of the region we studied Late Quaternary fluvial sediments found along several rivers that flow through that depression. Whereas Holocene river sediments could generally easily be assigned to corresponding rivers, this was not always the case for older fluvial sediments. For this reason, we studied the heavy mineral contents of five recent rivers and of four sedimentary deposits of potential precursors. A total of 4088 analysed heavy mineral grains enabled us to set up the characteristic heavy mineral distribution pattern for each sample. Using these data, we were able to reconstruct the most likely source areas of the Late Pleistocene fluvial sediments and to link them with the catchment areas of recent rivers. This allowed us to identify and to substantiate significant Late Quaternary river diversions that could at least partly be assigned to ongoing tectonic processes.

  9. The Bare Critical Assembly of Natural Uranium and Heavy Water

    Energy Technology Data Exchange (ETDEWEB)

    Popovic, D [Boris Kidric Institute of Nuclear Sciences, Vinca, Belgrade (Yugoslavia)

    1958-07-01

    The first reactor built in Yugoslavia was the bare zero energy heavy water and natural uranium assembly at the Boris Kidric Institute of Nuclear Sciences, Belgrade. The reactor went critical on April 29, 1958. The possession of four tons of natural uranium metal and the temporary availability of seven tons of heavy water encouraged the staff of the Institute to build a critical assembly. A critical assembly was chosen, rather than high flux reactor, because the heavy water was available only temporarily. Besides, a 10 MW, enriched uranium, research reactor is being built at the same Institute and should be ready for operation late this year. It was supposed that the zero energy reactor would provide experience in carrying out critical experiments, operational experience with nuclear reactors, and the possibility for an extensive program in reactor physics. (author)

  10. Vaginal bleeding in late pregnancy

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000627.htm Vaginal bleeding in late pregnancy To use the sharing ... JavaScript. One out of 10 women will have vaginal bleeding during their 3rd trimester. At times, it ...

  11. Heavy water upgrader of 'Fugen'

    International Nuclear Information System (INIS)

    Matsushita, Tadashi; Sasaki, Shigeo

    1980-01-01

    The nuclear power station of the advanced thermal prototype reactor ''Fugen'' has continued the smooth operation since it started the fullscale operation in March, 1979. Fugen is the first heavy water-moderated, boiling light water-cooled reactor in Japan, and its outstanding feature is the use of heavy water as the moderator. The quantity of heavy water retained in Fugen is about 140 m 3 , and the concentration is 99.8 wt.%. This heavy water had been made is USA, and was imported from F.R. of Germany where it had been used. Heavy water is an internationally regulated material, and it is very expensive and hard to purchase. Therefore in order to prevent the deterioration of heavy water and to avoid its loss as far as possible, the management of the quantity and the control of the water quality have been carried out carefully and strictly. The generation of deteriorated heavy water occurs from the exchange of ion exchange resin for poison removal and purification. The heavy water upgrader reconcentrates the deteriorated heavy water of high concentration and returns to the heavy water system, and it was installed for the purpose of reducing the purchase of supplementary heavy water. The outline of the heavy water upgrader, its construction, the performance test and the operation are described. (Kako, I.)

  12. Status of the accretion flow solution in the Golden Jubilee year of the discovery of extra-solar X-ray sources

    Science.gov (United States)

    Chakrabarti, S. K.

    Fifty years have just passed since the first discovery of the extra-solar X-ray sources by Giacconi and his team which we know today to be some stellar mass black holes. By 1973, not only a catalog of these enigmatic objects were made, and their spectra were obtained. Today, forty years have passed since the revolutionary idea of the thin, axisymmetric, Keplerian, disk model by Shakura and Sunyaev was published. Yet, the complete predictability of their radiative properties remains as illusive as ever. The only available and self-consistent solution to date is the generalized viscous transonic flow solutions where both heating and cooling effects are included. I demonstrate that the latest `Avatar' of the accretion/outflow picture, the Generalized Two Component Advective Flow (GTCAF), is capable of explaining almost all the black hole observational results, when the results of the time dependent simulation of viscous and radiative processes are also taken into consideration. I also discuss the problems with predictability and argue that understanding companion's behaviour in terms of its habit of mass loss, ellipticity of its orbit, magnetic properties, etc. is extremely important for the prediction of emission properties of the accretion flow.

  13. Late prematurity: a systematic review

    Directory of Open Access Journals (Sweden)

    Luís Carlos Machado Júnior

    2014-06-01

    Full Text Available Objective: this study aimed to review the literature regarding late preterm births (34 weeks to 36 weeks and 6 days of gestation in its several aspects. Sources: the MEDLINE, LILACS, and Cochrane Library databases were searched, and the references of the articles retrieved were also used, with no limit of time. Data synthesis: numerous studies showed a recent increase in late preterm births. In all series, late preterm comprised the majority of preterm births. Studies including millions of births showed a strong association between late preterm birth and neonatal mortality. A higher mortality in childhood and among young adults was also observed. Many studies found an association with several neonatal complications, and also with long-term disorders and sequelae: breastfeeding problems, cerebral palsy, asthma in childhood, poor school performance, schizophrenia, and young adult diabetes. Some authors propose strategies to reduce late preterm birth, or to improve neonatal outcome: use of antenatal corticosteroids, changes in some of the guidelines for early delivery in high-risk pregnancies, and changes in neonatal care for this group. Conclusions: numerous studies show greater mortality and morbidity in late preterm infants compared with term infants, in addition to long-term disorders. More recent studies evaluated strategies to improve the outcomes of these neonates. Further studies on these strategies are needed.

  14. Late effects from hadron therapy

    Energy Technology Data Exchange (ETDEWEB)

    Blakely, Eleanor A.; Chang, Polly Y.

    2004-06-01

    Successful cancer patient survival and local tumor control from hadron radiotherapy warrant a discussion of potential secondary late effects from the radiation. The study of late-appearing clinical effects from particle beams of protons, carbon, or heavier ions is a relatively new field with few data. However, new clinical information is available from pioneer hadron radiotherapy programs in the USA, Japan, Germany and Switzerland. This paper will review available data on late tissue effects from particle radiation exposures, and discuss its importance to the future of hadron therapy. Potential late radiation effects are associated with irradiated normal tissue volumes at risk that in many cases can be reduced with hadron therapy. However, normal tissues present within hadron treatment volumes can demonstrate enhanced responses compared to conventional modes of therapy. Late endpoints of concern include induction of secondary cancers, cataract, fibrosis, neurodegeneration, vascular damage, and immunological, endocrine and hereditary effects. Low-dose tissue effects at tumor margins need further study, and there is need for more acute molecular studies underlying late effects of hadron therapy.

  15. CHEMICAL ABUNDANCES IN THE EXTERNALLY POLLUTED WHITE DWARF GD 40: EVIDENCE OF A ROCKY EXTRASOLAR MINOR PLANET

    International Nuclear Information System (INIS)

    Klein, B.; Jura, M.; Zuckerman, B.; Melis, C.; Koester, D.

    2010-01-01

    We present Keck/High Resolution Echelle Spectrometer data with model atmosphere analysis of the helium-dominated polluted white dwarf GD 40, in which we measure atmospheric abundances relative to helium of nine elements: H, O, Mg, Si, Ca, Ti, Cr, Mn, and Fe. Apart from hydrogen, whose association with the other contaminants is uncertain, this material most likely accreted from GD 40's circumstellar dust disk whose existence is demonstrated by excess infrared emission. The data are best explained by accretion of rocky planetary material, in which heavy elements are largely contained within oxides, derived from a tidally disrupted minor planet at least the mass of Juno, and probably as massive as Vesta. The relatively low hydrogen abundance sets an upper limit of 10% water by mass in the inferred parent body, and the relatively high abundances of refractory elements, Ca and Ti, may indicate high-temperature processing. While the overall constitution of the parent body is similar to the bulk Earth being over 85% by mass composed of oxygen, magnesium, silicon, and iron, we find n(Si)/n(Mg) = 0.30 ± 0.11, significantly smaller than the ratio near unity for the bulk Earth, chondrites, the Sun, and nearby stars. This result suggests that differentiation occurred within the parent body.

  16. Late entry to antenatal care in New South Wales, Australia

    Directory of Open Access Journals (Sweden)

    Rubin George

    2006-08-01

    Full Text Available Abstract Aims This study aimed to assess the prevalence of women who entered antenatal care (ANC late and to identify factors related to the late entry to ANC in New South Wales (NSW in 2004. Methods The NSW Midwives Data Collection contained data of 85,034 women who gave birth in 2004. Data were downloaded using SAS and transferred to STATA 8.0. Entering ANC after 12 weeks of gestation was classified as late. The Andersen Health Seeking Behaviour Model was used for selection and analyses of related factors. Regression and hierarchical analyses were used to identify significant factors and their relative contributions to the variation of pregnancy duration at entry to ANC. Results 41% of women commenced ANC after 12 weeks of gestation. Inequality existed between groups of women with predisposing characteristics and enabling resources contributed more to the variation in pregnancy duration at entry to ANC than needs. The groups of women with highest risk were teenagers, migrants from developing countries, women living in Western Sydney, Aboriginal and Torres Strait Islanders, women with three or more previous pregnancies and heavy smokers. The high risk groups with largest number of women were migrants from developing countries and women living in Western Sydney. Conclusion A large number of women in NSW entered ANC late in their pregnancies. Efforts to increase early entry to ANC should be targeted on identified high risk groups of women.

  17. Heavy metals in our foodstuffs

    Energy Technology Data Exchange (ETDEWEB)

    1983-11-01

    The special group ''chemistry of food and forensic chemistry'' of the Association of German Analytical Chemists in Munich in 1983 issued a statement on that subject. The publication points out how heavy metals (examples: lead, cadmium and mercury) make their way into the foodstuffs, how many heavy metals are contained in our foodstuffs, which heavy metals are indispensable minerals and which aren't, and which heavy metals are ingested with food. It concludes by discussing how heavy metal contamination of our food can be prevented.

  18. Detecting heavy quarks

    International Nuclear Information System (INIS)

    Benenson, G.; Chau, L.L.; Ludlam, T.; Paige, F.E.; Platner, E.D.; Protopopescu, S.D.; Rehak, P.

    1983-01-01

    In this exercise we examine the performance of a detector specifically configured to tag heavy quark (HQ) jets through direct observations of D-meson decays with a high resolution vertex detector. To optimize the performance of such a detector, we assume the small diamond beam crossing configuration as described in the 1978 ISABELLE proposal, giving a luminosity of 10 32 cm -2 sec -1 . Because of the very large backgrounds from light quark (LQ) jets, most triggering schemes at this luminosity require high P/sub perpendicular to/ leptons and inevitably give missing neutrinos. If alternative triggering schemes could be found, then one can hope to find and calculate the mass of objects decaying to heavy quarks. A scheme using the high resolution detector will also be discussed in detail. The study was carried out with events generated by the ISAJET Monte Carlo and a computer simulation of the described detector system

  19. Drinking Level, Drinking Pattern, and Twenty-Year Total Mortality Among Late-Life Drinkers.

    Science.gov (United States)

    Holahan, Charles J; Schutte, Kathleen K; Brennan, Penny L; Holahan, Carole K; Moos, Rudolf H

    2015-07-01

    Research on moderate drinking has focused on the average level of drinking. Recently, however, investigators have begun to consider the role of the pattern of drinking, particularly heavy episodic drinking, in mortality. The present study examined the combined roles of average drinking level (moderate vs. high) and drinking pattern (regular vs. heavy episodic) in 20-year total mortality among late-life drinkers. The sample comprised 1,121 adults ages 55-65 years. Alcohol consumption was assessed at baseline, and total mortality was indexed across 20 years. We used multiple logistic regression analyses controlling for a broad set of sociodemographic, behavioral, and health status covariates. Among individuals whose high level of drinking placed them at risk, a heavy episodic drinking pattern did not increase mortality odds compared with a regular drinking pattern. Conversely, among individuals who engage in a moderate level of drinking, prior findings showed that a heavy episodic drinking pattern did increase mortality risk compared with a regular drinking pattern. Correspondingly, a high compared with a moderate drinking level increased mortality risk among individuals maintaining a regular drinking pattern, but not among individuals engaging in a heavy episodic drinking pattern, whose pattern of consumption had already placed them at risk. Findings highlight that low-risk drinking requires that older adults drink low to moderate average levels of alcohol and avoid heavy episodic drinking. Heavy episodic drinking is frequent among late-middle-aged and older adults and needs to be addressed along with average consumption in understanding the health risks of late-life drinkers.

  20. Heavy ion fusion III

    International Nuclear Information System (INIS)

    Hammer, D.; Max, C.; Perkins, F.; Rosenbluth, M.

    1987-03-01

    This report updates Heavy Ion Fusion, JSR-82-302, dated January, 1983. During the last four years, program management and direction has been changed and the overall Inertial Confinement Program has been reviewed. This report therefore concentrates on accelerator physics issues, how the program has addressed those issues during the last four years, and how it will be addressing them in the future. 8 refs., 3 figs

  1. Experimental heavy quarkonium physics

    International Nuclear Information System (INIS)

    Bugge, L.

    1986-08-01

    Following some brief arguments on why heavy quarkonium spectroscopy is an important field of particle physics, some points on experimental techniques are discussed. Parts of the basic quarkonium phenomenology, including discussions of various items related to potensial models, are then presented. An up-to-date presentation is given of the state-of-the-art of experimental charmonium and bottomonium spectroscopy below open flavour threshold, including the confrontation of experimental results to representative theoretical predictions

  2. Relativistic heavy ion reactions

    Energy Technology Data Exchange (ETDEWEB)

    Brink, D M

    1989-08-01

    The theory of quantum chromodynamics predicts that if nuclear matter is heated to a sufficiently high temperature then quarks might become deconfined and a quark-gluon plasma could be produced. One of the aims of relativistic heavy ion experiments is to search for this new state of matter. These lectures survey some of the new experimental results and give an introduction to the theories used to interpret them. 48 refs., 4 tabs., 11 figs.

  3. Carburetor for heavy oils

    Energy Technology Data Exchange (ETDEWEB)

    Gautreau, L

    1905-03-06

    This invention relates to a carburetor for heavy oils in which the combustion liquid circulates successively in two annular spaces at the top and bottom of the vaporizer heated by the gas from the outlet and returning from there, after having been conveniently heated, to the constant level by an appropriate tube; the constant level can be surrounded by an annular chamber in which circulates a part of the gas from the outlet.

  4. Relativistic heavy ion physics

    International Nuclear Information System (INIS)

    Hansen, O.

    1985-01-01

    In the fall of 1986 beams of heavy ions up to A ∼ 40 at total energies up to E ∼ 225 GeV/-nucleon will become available for experiments at CERN (60 and 225 GeV/nucleon) and at Brookhaven (15.5 GeV/nucleon). Are these energies interesting in relation to the ideas of creating quark deconfinement? An energy consideration of the planned experiments is presented, as well as a description of the experimental arrangement. (Auth.)

  5. Neutrinos: Heavy water detector

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The proponents of the Sudbury Neutrino Observatory (SNO) received a welcome Christmas present when William Winegard, Canadian Minister for Science and Technology announced the final details of the funding for this project, totalling 48 million Canadian dollars and including contributions from the US and the UK. The SNO experiment will extend significantly the study of solar neutrinos, using some 1,000 tonnes of heavy water to be installed more than two kilometres below ground in a nickel mine at Sudbury, Ontario

  6. Canadian heavy water production

    International Nuclear Information System (INIS)

    Dahlinger, A.; Lockerby, W.E.; Rae, H.K.

    1977-01-01

    The paper reviews Canadian experience in the production of heavy water, presents a long-term supply projection, relates this projection to the anticipated long-term electrical energy demand, and highlights principal areas for further improvement that form the bulk of the Canadian R and D programme on heavy water processes. Six Canadian heavy water plants with a total design capacity of 4000Mg/a are in operation or under construction. All use the Girdler-Sulphide (GS) process, which is based on deuterium exchange between water and hydrogen sulphide. Early operating problems have been overcome and the plants have demonstrated annual capacity factors in excess of 70%, with short-term production rates equal to design rates. Areas for further improvement are: to increase production rates by optimizing the control of foaming to give both higher sieve tray efficiency and higher flow rates, to reduce the incapacity due to deposition of pyrite (FeS 2 ) and sulphur (between 5% and 10%), and to improve process control and optimization of operating conditions by the application of mathematical simulations of the detailed deuterium profile throughout each plant. Other processes being studied, which look potentially attractive are the hydrogen-water exchange and the hydrogen-amine exchange. Even if they become successful competitors to the GS process, the latter is likely to remain the dominant production method for the next 10-20 years. This programme, when related to the long-term electricity demand, indicates that heavy water supply and demand are in reasonable balance and that the Candu programme will not be inhibited because of shortages of this commodity. (author)

  7. Relativistic heavy ion reactions

    International Nuclear Information System (INIS)

    Brink, D.M.

    1989-08-01

    The theory of quantum chromodynamics predicts that if nuclear matter is heated to a sufficiently high temperature then quarks might become deconfined and a quark-gluon plasma could be produced. One of the aims of relativistic heavy ion experiments is to search for this new state of matter. These lectures survey some of the new experimental results and give an introduction to the theories used to interpret them. 48 refs., 4 tabs., 11 figs

  8. Utah Heavy Oil Program

    Energy Technology Data Exchange (ETDEWEB)

    J. Bauman; S. Burian; M. Deo; E. Eddings; R. Gani; R. Goel; C.K. Huang; M. Hogue; R. Keiter; L. Li; J. Ruple; T. Ring; P. Rose; M. Skliar; P.J. Smith; J.P. Spinti; P. Tiwari; J. Wilkey; K. Uchitel

    2009-10-20

    The Utah Heavy Oil Program (UHOP) was established in June 2006 to provide multidisciplinary research support to federal and state constituents for addressing the wide-ranging issues surrounding the creation of an industry for unconventional oil production in the United States. Additionally, UHOP was to serve as an on-going source of unbiased information to the nation surrounding technical, economic, legal and environmental aspects of developing heavy oil, oil sands, and oil shale resources. UHOP fulGilled its role by completing three tasks. First, in response to the Energy Policy Act of 2005 Section 369(p), UHOP published an update report to the 1987 technical and economic assessment of domestic heavy oil resources that was prepared by the Interstate Oil and Gas Compact Commission. The UHOP report, entitled 'A Technical, Economic, and Legal Assessment of North American Heavy Oil, Oil Sands, and Oil Shale Resources' was published in electronic and hard copy form in October 2007. Second, UHOP developed of a comprehensive, publicly accessible online repository of unconventional oil resources in North America based on the DSpace software platform. An interactive map was also developed as a source of geospatial information and as a means to interact with the repository from a geospatial setting. All documents uploaded to the repository are fully searchable by author, title, and keywords. Third, UHOP sponsored Give research projects related to unconventional fuels development. Two projects looked at issues associated with oil shale production, including oil shale pyrolysis kinetics, resource heterogeneity, and reservoir simulation. One project evaluated in situ production from Utah oil sands. Another project focused on water availability and produced water treatments. The last project considered commercial oil shale leasing from a policy, environmental, and economic perspective.

  9. Outlook for Saskatchewan heavy oil

    International Nuclear Information System (INIS)

    Youzwa, P.

    1993-01-01

    Some of the opportunities and challenges currently facing the heavy oil industry in Saskatchewan are discussed from a government perspective. By the end of September 1993, 220 heavy oil wells were drilled in the province, and 26% of the land sales in 1993 were in heavy oil areas. About 41% of the wells drilled in heavy oil areas were horizontal oil wells. Of the total horizontal wells drilled in Saskatchewan, 48% are for heavy oil, and horizontal well production averages 85 bbl/d. Initial trends suggest that horizontal wells both accelerate production and contribute to ultimate recovery. Total heavy oil production in 1992 reached 28.9 million bbl and recoverable reserves in 1991 were 262.3 million bbl, or 1.5% of total oil in place. The low recovery is not only due to technical factors such as high viscosity but also to low investment in the heavy oil sector due to poor economics. It is hoped that lower interest and exchange rates, the success of horizontal wells and the provincial royalty structure will maintain the recent increase in heavy oil activity. The provincial government recently launched a comprehensive energy strategy in which development of a heavy oil strategy is an important component. Total heavy oil reserves exceed those of light and medium oil and have significant development potential. The Saskatchewan government wishes to adopt a cooperative and partnership approach in its dealings with the heavy oil industry to help realize this potential. 9 figs

  10. Heavy ion transfer reactions

    International Nuclear Information System (INIS)

    Weisser, D.C.

    1977-06-01

    To complement discussions on the role of γ rays in heavy ion induced reactions, the author discusses the role played by particle detection. Transfer reactions are part of this subject and are among those in which one infers the properties of the residual nucleus in a reaction by observing the emerging light nucleus. Inelastic scattering ought not be excluded from this subject, although no particles are transferred, because of the role it plays in multistep reactions and in fixing O.M. parameters describing the entrance channel of the reaction. Heavy ion transfer reaction studies have been under study for some years and yet this research is still in its infancy. The experimental techniques are difficult and the demands on theory rigorous. One of the main products of heavy ion research has been the thrust to re-examine the assumptions of reaction theory and now include many effects neglected for light ion analysis. This research has spurred the addition of multistep processes to simple direct processes and coupled channel calculations. (J.R.)

  11. Heavy ion fusion

    International Nuclear Information System (INIS)

    Hofmann, Ingo

    1993-01-01

    With controlled thermonuclear fusion holding out the possibility of a prolific and clean new source of energy, the goal remains elusive after many years of continual effort. While the conventional Tokamak route with magnetic confinement continues to hit the headlines, other alternatives are now becoming competitive. One possible solution is to confine the thermonuclear fuel pellet by high power beams. Current research and perspectives for future work in such inertial confinement was the subject of the 'Prospects for Heavy Ion Fusion' European Research Conference held in Aghia Pelaghia, Crete, last year. Its main focus was on the potential of heavy ion accelerators as well as recent advances in target physics with high power lasers and light ion beams. Carlo Rubbia declared that high energy accelerators, with their high efficiency, are the most promising approach to economical fusion energy production. However the need for cost saving in the driver accelerator requires new ideas in target design tailored to the particularities of heavy ion beams, which need to be pushed to the limits of high current and phase space density at the same time

  12. Heavy flavor spectroscopy

    International Nuclear Information System (INIS)

    Rosen, J.; Marques, J.; Spiegel, L.

    1993-09-01

    As a useful by-product of the unfolding searches for mixing and CP-violation effects in the beauty sector there will accrue very large data samples for the study of heavy flavor spectroscopy. Interest in this field may be provisionally divided into two general classes: Hidden flavor states, i.e. c bar c and b bar b onium states; open flavor states: The D, D s , B, B s , and B c meson systems; and charm and beauty flavored baryons. In this brief note we emphasize that there are many missing states in both categories -- states which are not readily produced exclusively due to quantum number preferences or states which are not readily observed inclusively due to experimentally difficult decay channels. As recorded luminosities increase it may be possible to fill in some of the holes in the present listings of heavy flavor states. Of particular interest to us would be the identification of heavy flavor mesons which are not easily explained in terms of a q bar q paradigm but rather may be evidence for hadro-molecular states. At Snowmass 1993 the topic of self-tagging schemes in B meson production was very much in vogue. Whether or not excited B-meson flavor-tagging will prove to be competitive with traditional methods based on the partner bar B decay remains to be seen. We suggest however that the richness of the excited B-system may undermine the efficacy of self-tagging schemes

  13. Searching for heavy leptons

    International Nuclear Information System (INIS)

    Perl, M.L.

    1979-11-01

    This frankly speculative paper discusses ways in which leptons heavier than the tau (if they exist) might be found. The status of the tau is briefly reviewed, and methods for searching for sequential charged leptons beyond the tau and other charged leptons at PEP, PETRA, and CESR are sketched. Charged leptons with mass greater than 20 GeV/c 2 might be found at proton accelerators in hadron-hadron, photon-hadron, or ν-hadron collisions. Unstable, neutral heavy leptons might have unique, conserved lepton number or nonunique lepton number. The most difficult leptons to detect are stable neutral heavy leptons; nevertheless, a possible detection method is suggested. The obvious solution to seeking the postulated leptons is an e + e - colliding beam storage ring with c.m. energy = several hundred GeV. Until such a machine is built, one can employ Z 0 → L + + L - ; the use of R/sub Z 0 / and GAMMA/sub Z 0 / in this connection is discussed. If heavier Z 0 's exist, the heavy lepton search can be extended to higher energies. Another solution for producing these leptons involves the use of clashing e + e - linear accelerators. Characteristics of storage rings are compared with those of clashing linacs; a general description is given of the proposed SLAC Linac-Collider, along with the physics that could be done at such a machine. 6 figures

  14. Heavy flavor spectroscopy

    International Nuclear Information System (INIS)

    Rosen, J.; Marques, J.; Spiegel, L.

    1993-01-01

    As a useful by-product of the unfolding searches for mixing and CP-violation effects in the beauty sector there will accrue very large data samples for the study of heavy flavor spectroscopy. (I) Hidden flavor states, i.e. c bar c and b bar b onium states. (II) Open flavor states (a) the D, D s , B, B s , and B c meson systems; (b) Charm and beauty flavored baryons. In this brief note the authors emphasize that there are many missing (undiscovered) states in both categories - states which are not readily produced exclusively due to quantum number preferences or states which are not readily observed inclusively due to experimentally difficult decay channels. As recorded luminosities increase it may be possible to fill in some of the holes in the present listings of heavy flavor states. Of particular interest to the authors would be the identification of heavy flavor mesons which are not easily explained in terms of a q bar q paradigm but rather may be evidence for hadro-molecular status. At Snowmass 1993 the topic of self-tagging schemes in B meson production was very much in vogue. Whether or not excited B-meson flavor-tagging will prove to be competitive with traditional methods based on the partner B decay remains to be seen. The authors suggest however that the richness of the excited B-system may undetermine the efficacy of self-tagging schemes

  15. Heavy ion inertial fusion

    International Nuclear Information System (INIS)

    Fessenden, T.J.; Friedman, A.

    1991-01-01

    This report describes the research status in the following areas of research in the field of heavy ion inertial fusion: (1) RF accelerators, storage rings, and synchrotrons; (2) induction linacs; (3) recirculation induction accelerator approach; (4) a new accelerator concept, the ''Mirrortron''; (5) general issues of transport, including beam merging, production of short, fat quadrupoles with nearly linear focusing, calculations of beam behaviour in image fields; 3-D electrostatic codes on drift compression with misalignments and transport around bends; (6) injectors, ion sources and RFQs, a.o., on the development of a 27 MHz RFQ to be used for the low energy portion of a new injector for all ions up to Uranium, and the development of a 2 MV carbon ion injector to provide 16 C + beams of 0.5 A each for ILSE; (7) beam transport from accelerator to target, reporting, a.o., the feasibility to suppress third-order aberrations; while Particle-in-Cell simulations on the propagation of a non-neutral ion beam in a low density gas identified photo-ionization by thermal X-rays from the target as an important source of defocusing; (9) heavy ion target studies; (10) reviewing experience with laser drivers; (11) ion cluster stopping and muon catalyzed fusion; (12) heavy ion systems, including the option of a fusion-fission burner. 1 tab

  16. SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems

    International Nuclear Information System (INIS)

    Eisenstein, Daniel J.; Weinberg, David H.; Agol, Eric; Aihara, Hiroaki; Prieto, Carlos Allende; Anderson, Scott F.; Arns, James A.; Aubourg, Eric; Bailey, Stephen; Balbinot, Eduardo; Barkhouser, Robert

    2011-01-01

    Building on the legacy of the Sloan Digital Sky Survey (SDSS-I and II), SDSS-III is a program of four spectroscopic surveys on three scientific themes: dark energy and cosmological parameters, the history and structure of the Milky Way, and the population of giant planets around other stars. The Baryon Oscillation Spectroscopic Survey (BOSS) will measure redshifts of 1.5 million massive galaxies and Lyα forest spectra of 150,000 quasars, using the baryon acoustic oscillation (BAO) feature of large scale structure to obtain percent-level determinations of the distance scale and Hubble expansion rate at z 5 evolved, late-type stars, measuring separate abundances for ∼ 15 elements per star and creating the first high-precision spectroscopic survey of all Galactic stellar populations (bulge, bar, disks, halo) with a uniform set of stellar tracers and spectral diagnostics. The Multi-object APO Radial Velocity Large-area Survey (MARVELS) will monitor radial velocities of more than 8000 FGK stars with the sensitivity and cadence (10-40 m s -1 , ∼ 24 visits per star) needed to detect giant planets with periods up to two years, providing an unprecedented data set for understanding the formation and dynamical evolution of giant planet systems. As of January 2011, SDSS-III has obtained spectra of more than 240,000 galaxies, 29,000 z (ge) 2.2 quasars, and 140,000 stars, including 74,000 velocity measurements of 2580 stars for MARVELS. In keeping with SDSS tradition, SDSS-III will provide regular public releases of all its data, beginning with SDSS Data Release 8 (DR8) in January 2011.

  17. SDSS-III: MASSIVE SPECTROSCOPIC SURVEYS OF THE DISTANT UNIVERSE, THE MILKY WAY, AND EXTRA-SOLAR PLANETARY SYSTEMS

    International Nuclear Information System (INIS)

    Eisenstein, Daniel J.; Weinberg, David H.; Agol, Eric; Anderson, Scott F.; Aihara, Hiroaki; Allende Prieto, Carlos; Arns, James A.; Aubourg, Eric; Bailey, Stephen; Balbinot, Eduardo; Barkhouser, Robert; Beers, Timothy C.; Berlind, Andreas A.; Bickerton, Steven J.; Bizyaev, Dmitry; Blanton, Michael R.; Bochanski, John J.; Bolton, Adam S.

    2011-01-01

    Building on the legacy of the Sloan Digital Sky Survey (SDSS-I and II), SDSS-III is a program of four spectroscopic surveys on three scientific themes: dark energy and cosmological parameters, the history and structure of the Milky Way, and the population of giant planets around other stars. In keeping with SDSS tradition, SDSS-III will provide regular public releases of all its data, beginning with SDSS Data Release 8 (DR8), which was made public in 2011 January and includes SDSS-I and SDSS-II images and spectra reprocessed with the latest pipelines and calibrations produced for the SDSS-III investigations. This paper presents an overview of the four surveys that comprise SDSS-III. The Baryon Oscillation Spectroscopic Survey will measure redshifts of 1.5 million massive galaxies and Lyα forest spectra of 150,000 quasars, using the baryon acoustic oscillation feature of large-scale structure to obtain percent-level determinations of the distance scale and Hubble expansion rate at z 5 evolved, late-type stars, measuring separate abundances for ∼15 elements per star and creating the first high-precision spectroscopic survey of all Galactic stellar populations (bulge, bar, disks, halo) with a uniform set of stellar tracers and spectral diagnostics. The Multi-object APO Radial Velocity Exoplanet Large-area Survey (MARVELS) will monitor radial velocities of more than 8000 FGK stars with the sensitivity and cadence (10-40 m s -1 , ∼24 visits per star) needed to detect giant planets with periods up to two years, providing an unprecedented data set for understanding the formation and dynamical evolution of giant planet systems. As of 2011 January, SDSS-III has obtained spectra of more than 240,000 galaxies, 29,000 z ≥ 2.2 quasars, and 140,000 stars, including 74,000 velocity measurements of 2580 stars for MARVELS.

  18. Heavy-heavy and heavy-light quarks interactions generated by QCD vacuum

    Directory of Open Access Journals (Sweden)

    Musakhanov Mirzayusuf

    2017-01-01

    Full Text Available The QCD vacuum is populated by instantons that correspond to the tunneling processes in the vacuum. This mechanism creates the strong vacuum gluon fields. As result, the QCD vacuum instantons induce very strong interactions between light quarks, initially almost massless. Such a strong interactions bring a large dynamical mass M of the light quarks and bound them to produce almost massless pions in accordance with the spontaneous breaking of the chiral symmetry (SBCS. On the other hand, the QCD vacuum instantons also interact with heavy quarks and responsible for the generation of the heavy-heavy and heavy-light quarks interactions, with a traces of the SBCS. If we take the average instanton size ρ¯=0.33$\\bar \\rho = 0.33$ fm, and the average inter-instanton distance R¯=1$\\bar R = 1$ fm we obtain the dynamical light quark mass to be M = 365 MeV and the instanton media contribution to the heavy quark mass ΔM=70 MeV. These factors define the coupling between heavy-light and heavy-heavy quarks induced by the QCD vacuum instantons. We consider first the instanton effects on the heavy-heavy quarks potential, including its spin-dependent part. We also discuss those effects on the masses of the charmonia and their hyperfine mass splittings. At the second part we discuss the interaction between a heavy and light quarks generated by instantons and it’s effects.

  19. Determination of heavy water in heavy water - light water mixtures

    International Nuclear Information System (INIS)

    Sanhueza M, A.

    1986-01-01

    A description about experimental methodology to determine isotopic composition of heavy water - light water mixtures is presented. The employed methods are Nuclear Magnetic Resonance Spectroscopy, for measuring heavy water concentrations from 0 to 100% with intervals of 10% approx., and mass Spectrometry, for measuring heavy water concentrations from 0.1 to 1% with intervals of 0.15% approx., by means of an indirect method of Dilution. (Author)

  20. Recent casualties of late globalization

    DEFF Research Database (Denmark)

    Turcan, Romeo V.

    2016-01-01

    In this essay I will expand my thoughts on universities as ‘late globalizers’ and the impact ‘being late’ has on university internationalization or globalization activities. In my earlier essay I viewed universities as ‘late globalizers’ and briefly introduced the impact of being ‘late’, e.g., wi.......g., withdrawal or de-internationalization of universities due to incompatibility between university autonomy and the context in the target country or universities unwillingness to compromise on their freedom and autonomy....

  1. Heavy water upgrading system in the Fugen heavy water reactor

    International Nuclear Information System (INIS)

    Matsushita, T.; Susaki, S.

    1980-01-01

    The heavy water upgrading system, which is installed in the Fugen heavy water reactor (HWR) was designed to reuse degraded heavy water generated from the deuteration-dedeuteration of resin in the ion exchange column of the moderator purification system. The electrolysis method has been applied in this system on the basis of the predicted generation rate and concentration of degraded heavy water. The structural feature of the electrolytic cell is that it consists of dual cylindrical electrodes, instead of a diaphragm as in the case of conventional water electrolysis. 2 refs

  2. SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems

    Energy Technology Data Exchange (ETDEWEB)

    Eisenstein, Daniel J.; /Arizona U., Astron. Dept. - Steward Observ. /Harvard U., Phys. Dept.; Weinberg, David H.; /Ohio State U.; Agol, Eric; /Washington U., Seattle, Astron. Dept.; Aihara, Hiroaki; /Tokyo U.; Prieto, Carlos Allende; /Laguna U., Tenerife; Anderson, Scott F.; /Washington U., Seattle, Astron. Dept.; Arns, James A.; /Michigan U.; Aubourg, Eric; /APC, Paris /DAPNIA, Saclay; Bailey, Stephen; /LBL, Berkeley; Balbinot, Eduardo; /Rio Grande do Sul U. /Rio de Janeiro Observ.; Barkhouser, Robert; /Johns Hopkins U. /Michigan State U.

    2011-01-01

    Building on the legacy of the Sloan Digital Sky Survey (SDSS-I and II), SDSS-III is a program of four spectroscopic surveys on three scientific themes: dark energy and cosmological parameters, the history and structure of the Milky Way, and the population of giant planets around other stars. The Baryon Oscillation Spectroscopic Survey (BOSS) will measure redshifts of 1.5 million massive galaxies and Ly{alpha} forest spectra of 150,000 quasars, using the baryon acoustic oscillation (BAO) feature of large scale structure to obtain percent-level determinations of the distance scale and Hubble expansion rate at z < 0.7 and at z {approx} 2.5. SEGUE-2, a now-completed continuation of the Sloan Extension for Galactic Understanding and Exploration, measured medium-resolution (R = {lambda}/{Delta}{lambda} 1800) optical spectra of 118,000 stars in a variety of target categories, probing chemical evolution, stellar kinematics and substructure, and the mass profile of the dark matter halo from the solar neighborhood to distances of 100 kpc. APOGEE, the Apache Point Observatory Galactic Evolution Experiment, will obtain high-resolution (R {approx} 30,000), high signal-to-noise ratio (S/N {ge} 100 per resolution element), H-band (1.51 {micro}m < {lambda} < 1.70 {micro}m) spectra of 10{sup 5} evolved, late-type stars, measuring separate abundances for {approx} 15 elements per star and creating the first high-precision spectroscopic survey of all Galactic stellar populations (bulge, bar, disks, halo) with a uniform set of stellar tracers and spectral diagnostics. The Multi-object APO Radial Velocity Large-area Survey (MARVELS) will monitor radial velocities of more than 8000 FGK stars with the sensitivity and cadence (10-40 m s{sup -1}, {approx} 24 visits per star) needed to detect giant planets with periods up to two years, providing an unprecedented data set for understanding the formation and dynamical evolution of giant planet systems. As of January 2011, SDSS-III has obtained

  3. Heavy Truck Engine Program

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Christopher

    2009-01-08

    The Heavy Duty Truck Engine Program at Cummins embodied three significant development phases. All phases of work strove to demonstrate a high level of diesel engine efficiency in the face of increasingly stringent emission requirements. Concurrently, aftertreatment system development and refinement was pursued in support of these efficiency demonstrations. The program's first phase focused on the demonstration in-vehicle of a high level of heavy duty diesel engine efficiency (45% Brake Thermal Efficiency) at a typical cruise condition while achieving composite emissions results which met the 2004 U.S. EPA legislated standards. With a combination of engine combustion calibration tuning and the development and application of Urea-based SCR and particulate aftertreatment, these demonstrations were successfully performed by Q4 of 2002. The second phase of the program directed efforts towards an in-vehicle demonstration of an engine system capable of meeting 2007 U.S. EPA legislated emissions requirements while achieving 45% Brake Thermal Efficiency at cruise conditions. Through further combustion optimization, the refinement of Cummins Cooled EGR architecture, the application of a high pressure common rail fuel system and the incorporation of optimized engine parasitics, Cummins Inc. successfully demonstrated these deliverables in Q2 of 2004. The program's final phase set a stretch goal of demonstrating 50% Brake Thermal Efficiency from a heavy duty diesel engine system capable of meeting 2010 U.S. EPA legislated emissions requirements. Cummins chose to pursue this goal through further combustion development and refinement of the Cooled EGR system architecture and also applied a Rankine cycle Waste Heat Recovery technique to convert otherwise wasted thermal energy to useful power. The engine and heat recovery system was demonstrated to achieve 50% Brake Thermal Efficiency while operating at a torque peak condition in second quarter, 2006. The 50% efficient

  4. Holifield Heavy Ion Research Facility. Phase II

    International Nuclear Information System (INIS)

    Ball, J.B.; Hudson, E.D.; Lord, R.S.; Johnson, J.W.; Martin, J.A.; McNeilly, G.S.; Milner, W.T.; Mosko, S.W.; Sayer, R.O.; Robinson, R.L.

    1979-01-01

    The Holifield Heavy Ion Research Facility, with the completion of Phase I in late 1979, will include the Oak Ridge Isochronous Cyclotron (ORIC) and associated research areas, the new 25 MV tandem accelerator with new research areas for tandem beams, and modifications to utilize the ORIC as a booster accelerator. The combination of the tandem and ORIC will provide beam energies of 25 MeV/A for light heavy ions and 6 MeV/A up to A = 160. This paper discusses plans for a Phase II expansion of the facility to include an isochronous cyclotron with superconducting magnet and reconfiguration of the existing research areas and the ORIC vault to handle the higher energy beams from the new cyclotron. The new booster cyclotron is a low-flutter high-spiral design patterned after the MSU K = 800 design, with a central magnetic field of about 5 tesla and an extraction radius of 1 meter. The new beam transport system will incorporate an rf beam-splitter system that will be able to deliver successive beam pulses to two or three experiment areas

  5. Trends in heavy oil production and refining in California

    International Nuclear Information System (INIS)

    Olsen, D.K.; Ramzel, E.B.; Pendergrass, R.A. II.

    1992-07-01

    This report is one of a series of publications assessing the feasibility of increasing domestic heavy oil production and is part of a study being conducted for the US Department of Energy. This report summarizes trends in oil production and refining in Canada. Heavy oil (10 degrees to 20 degrees API gravity) production in California has increased from 20% of the state's total oil production in the early 1940s to 70% in the late 1980s. In each of the three principal petroleum producing districts (Los Angeles Basin, Coastal Basin, and San Joaquin Valley) oil production has peaked then declined at different times throughout the past 30 years. Thermal production of heavy oil has contributed to making California the largest producer of oil by enhanced oil recovery processes in spite of low oil prices for heavy oil and stringent environmental regulation. Opening of Naval Petroleum Reserve No. 1, Elk Hills (CA) field in 1976, brought about a major new source of light oil at a time when light oil production had greatly declined. Although California is a major petroleum-consuming state, in 1989 the state used 13.3 billion gallons of gasoline or 11.5% of US demand but it contributed substantially to the Nation's energy production and refining capability. California is the recipient and refines most of Alaska's 1.7 million barrel per day oil production. With California production, Alaskan oil, and imports brought into California for refining, California has an excess of oil and refined products and is a net exporter to other states. The local surplus of oil inhibits exploitation of California heavy oil resources even though the heavy oil resources exist. Transportation, refining, and competition in the market limit full development of California heavy oil resources

  6. Heavy fragment radioactivity

    International Nuclear Information System (INIS)

    Silisteanu, I.

    1991-06-01

    The effect of collective mode excitation in heavy fragment radioactivity (HFR) is explored and discussed in the light of current experimental data. It is found that the coupling and resonance effects in fragment interaction and also the proper angular momentum effects may lead to an important enhancing of the emission process. New useful procedures are proposed for the study of nuclear decay properties. The relations between different decay processes are investigated in detail. We are also trying to understand and explain in a unified way the reaction mechanisms in decay phenomena. (author). 17 refs, 4 figs, 3 tabs

  7. Fission of heavy hypernuclei

    International Nuclear Information System (INIS)

    Nifenecker, H.

    1993-01-01

    The results on delayed and prompt fission of heavy hypernuclei obtained by the LEAR PS177 collaboration are recalled and discussed. It is shown that the hypernuclei life-times can be explained in term of a weak strangeness violating lambda-nucleon interaction with a cross section close to 6.0 10 -15 barns. The lambda attachment function is shown to be sensitive to the scission configuration, just before fission, and to the neck dynamics. This function provides a new way to study the nuclear scission process. (author)

  8. Heavy gas valves

    Energy Technology Data Exchange (ETDEWEB)

    Steier, L [Vereinigte Armaturen Gesellschaft m.b.H., Mannheim (Germany, F.R.)

    1979-01-01

    Heavy gas valves must comply with special requirements. Apart from absolute safety in operation there are stringent requirements for material, sealing and ease of operation even in the most difficult conditions. Ball valves and single plate pipe gate valves lateral sealing rings have a dual, double sided sealing effect according to the GROVE sealing system. Single plate gate valves with lateral protective plates are suitable preferably for highly contaminated media. Soft sealing gate valves made of cast iron are used for low pressure applications.

  9. Relativistic heavy ion collisions

    International Nuclear Information System (INIS)

    Barz, H.W.; Kaempfer, B.; Schulz, H.

    1984-12-01

    An elementary introduction is given into the scenario of relativistic heavy ion collisions. It deals with relativistic kinematics and estimates of energy densities, extrapolations of the present knowledge of hadron-hadron and hadron-nuleus to nucleus-nucleus collisions, the properties of the quark-gluon plasma and the formation of the plasma and possible experimental signatures. Comments are made on a cosmic ray experiment which could be interpreted as a first indication of the quark-gluon phase of the matter. (author)

  10. Heavy Quarkonium Physics

    CERN Document Server

    CERN. Geneva; Krämer, Michael; Mussa, Roberto; Vairo, Antonio; Bali, G S; Bodwin, G T; Braaten, E; Eichten, E; Eidelman, S; Godfrey, S; Hoang, A; Jamin, M; Kharzeev, Dima E; Lombardo, M P; Lourenço, C; Meyer, A B; Papadimitriou, V; Patrignani, C; Rosati, M; Sanchis-Lozano, M A; Satz, Helmut; Soto, J; Besson, D Z; Bettoni, D; Böhrer, A; Boogert, S; Chang, C H; Cooper, P; Crochet, Philippe; Datta, S; Davies, C; Deandrea, A; Faustov, R; Ferguson, T; Galik, R; Harris, F; Iouchtchenko, O; Kaczmarek, O; Karsch, Frithjof; Kienzle, M; Kiselev, V V; Klein, S R; Kroll, P; Kronfeld, A S; Kuang Yu Ping; Laporta, V; Lee, J; Leibovich, A K; Ma, J P; MacKenzie, P; Maiani, Luciano; Mangano, Michelangelo L; Meyer, A; Mo, X H; Morningstar, C; Nairz, A; Napolitano, J; Olsen, S; Penin, A A; Petreczky, P; Piccinini, F; Pineda, A; Polosa, Antonio; Ramello, L; Rapp, R; Richard, J M; Riquer, V; Ricciardi, S; Robutti, E; Schneider, O; Scomparin, E; Simone, J; Skwarnicki, T; Stancari, G; Stewart, I W; Sumino, Y; Teubner, T; Tseng, J; Vogt, R; Wang, P; Yabsley, B D; Yuan, C Z; Zantow, F; Zhao, Z G; Zieminski, A

    2005-01-01

    This report is the result of the collaboration and research effort of the Quarkonium Working Group over the last three years. It provides a comprehensive overview of the state of the art in heavy-quarkonium theory and experiment, covering quarkonium spectroscopy, decay, and production, the determination of QCD parameters from quarkonium observables, quarkonia in media, and the effects on quarkonia of physics beyond the Standard Model. An introduction to common theoretical and experimental tools is included. Future opportunities for research in quarkonium physics are also discussed.

  11. Heavy transport problems

    International Nuclear Information System (INIS)

    Haas, K.F.

    1975-01-01

    Assuming that very often a long transport route from the factory of the manufacturer to the provided site has to be reckoned with, in general only transport with a ship is possible. As each site is only called by a certain steamship line, at a very early stage of planning the nuclear power plant the possibilities and capacities of the lines and means of transportation under discussion should be investigated. In planning the unloading equipment at the site, due consideration should be given to the fact that at a later time this equipment should also be suitable for the transport of heavy components and spent fuel assemblies. (orig.) [de

  12. Heavy Quark Effective Theory

    Science.gov (United States)

    Manohar, A. V.

    2003-02-01

    These lecture notes present some of the basic ideas of heavy quark effective theory. The topics covered include the classification of states, the derivation of the HQET Lagrangian at tree level, hadron masses, meson form factors, Luke's theorem, reparameterization invariance and inclusive decays. Radiative corrections are discussed in some detail, including an explicit computation of a matching correction for HQET. Borel summability, renormalons, and their connection with the QCD perturbation series is covered, as well as the use of the upsilon expansion to improve the convergence of the perturbation series.

  13. Heavy ion storage rings

    International Nuclear Information System (INIS)

    Schuch, R.

    1987-01-01

    A brief overview of synchrotron storage rings for heavy ions, which are presently under construction in different accelerator laboratories is given. Ions ranging from protons up to uranium ions at MeV/nucleon energies will be injected into these rings using multiturn injection from the accelerators available or being built in these laboratories. After injection, it is planned to cool the phase space distribution of the ions by merging them with cold electron beams or laser beams, or by using stochastic cooling. Some atomic physics experiments planned for these rings are presented. 35 refs

  14. [Relativistic heavy ion research

    International Nuclear Information System (INIS)

    1991-01-01

    The present document describes our second-year application for a continuation grant on relativistic heavy-ion research at Nevis Laboratories, Columbia University, over the two-year period starting from November 15, 1990. The progress during the current budget year is presented. This year, construction of RHIC officially began. As a result, the entire Nevis nuclear physics group has made a coherent effort to create new proposal for an Open Axially Symmetric Ion Spectrometer (OASIS) proposal. Future perspectives and our plans for this proposal are described

  15. Heavy ion therapy: Bevalac epoch

    International Nuclear Information System (INIS)

    Castro, J.R.

    1993-10-01

    An overview of heavy ion therapy at the Bevelac complex (SuperHILac linear accelerator + Bevatron) is given. Treatment planning, clinical results with helium ions on the skull base and uveal melanoma, clinical results with high-LET charged particles, neon radiotherapy of prostate cancer, heavy charged particle irradiation for unfavorable soft tissue sarcoma, preliminary results in heavy charged particle irradiation of bone sarcoma, and irradiation of bile duct carcinoma with charged particles and-or photons are all covered

  16. Spectroscopy of doubly heavy baryons

    International Nuclear Information System (INIS)

    Gershtein, S.S.; Kiselev, V.V.; Likhoded, A.K.; Onishchenko, A.I.

    2000-01-01

    Within a nonrelativistic quark model featuring a QCD-motivated Buchmueller-Tye potential, the mass spectra for the families of doubly heavy baryons are calculated by assuming the quark-diquark structure of the baryon wave functions and by taking into account spin-dependent splitting. Physically motivated evidence that, in the case where heavy quarks have identical flavors, quasistationary excited states may be formed in the heavy-diquark subsystem is analyzed

  17. Relativistic heavy-ion physics

    CERN Document Server

    Herrera Corral, G

    2010-01-01

    The study of relativistic heavy-ion collisions is an important part of the LHC research programme at CERN. This emerging field of research focuses on the study of matter under extreme conditions of temperature, density, and pressure. Here we present an introduction to the general aspects of relativistic heavy-ion physics. Afterwards we give an overview of the accelerator facility at CERN and then a quick look at the ALICE project as a dedicated experiment for heavy-ion collisions.

  18. Heavy quark production and spectroscopy

    International Nuclear Information System (INIS)

    Appel, J.A.

    1993-11-01

    This review covers many new experimental results on heavy flavor production and spectroscopy. It also shows some of the increasingly improved theoretical understanding of results in light of basic perturbative QCD and heavy quark symmetry. At the same time, there are some remaining discrepancies among experiments as well as significant missing information on some of the anticipated lowest lying heavy quark states. Most interesting, perhaps, are some clearly measured production effects awaiting full explanation

  19. Late onset globoid cell leukodystrophy.

    OpenAIRE

    Grewal, R P; Petronas, N; Barton, N W

    1991-01-01

    A 29 year old male with onset of globoid cell leukodystrophy at age 14 is described. This is the first case of enzymatically confirmed globoid cell leukodystrophy with onset of symptoms after the age of ten. This patient is unique because of the late onset and slow progression and extends the clinical spectrum of globoid cell leukodystrophy.

  20. Late onset globoid cell leukodystrophy.

    Science.gov (United States)

    Grewal, R P; Petronas, N; Barton, N W

    1991-11-01

    A 29 year old male with onset of globoid cell leukodystrophy at age 14 is described. This is the first case of enzymatically confirmed globoid cell leukodystrophy with onset of symptoms after the age of ten. This patient is unique because of the late onset and slow progression and extends the clinical spectrum of globoid cell leukodystrophy.

  1. Early and Late Retirement Exits

    Science.gov (United States)

    Brougham, Ruby R.; Walsh, David A.

    2009-01-01

    The current study proposes that personal need fulfillment (relatedness, generativity, identity, growth, and finances) predicts early and late retirement intentions. The personal needs of 160 full-time older employees were measured by personal goals, job satisfactions, job characteristics, and intrinsic motivation. Results suggest that the personal…

  2. Late onset startle induced tics

    NARCIS (Netherlands)

    Tijssen, MAJ; Brown, P; Morris, HR; Lees, A

    1999-01-01

    Three cases of late onset Gilles de la Tourette's syndrome are presented. The motor ties were mainly induced by an unexpected startling stimulus, but the startle reflex was not exaggerated. The ties developed after physical trauma or a period of undue emotional stress. Reflex ties may occur in

  3. Late onset startle induced tics

    NARCIS (Netherlands)

    Tijssen, M. A.; Brown, P.; Morris, H. R.; Lees, A.

    1999-01-01

    Three cases of late onset Gilles de la Tourette's syndrome are presented. The motor tics were mainly induced by an unexpected startling stimulus, but the startle reflex was not exaggerated. The tics developed after physical trauma or a period of undue emotional stress. Reflex tics may occur in

  4. Heavy quark spectroscopy

    International Nuclear Information System (INIS)

    Rosner, J.L.

    1985-10-01

    New experimental and theoretical developments in heavy quark spectroscopy are reviewed. From studies of J/psi decays, the eta' is found to have some ''glue'' or other inert component, while the iota (a glueball candidate) probably contains some quarks as well. The xi(2.2) persists in new Mark III data, but is not seen by the DM2 collaboration. The production of charmonium states by anti pp reactions is reviewed. First evidence for a P- wave charmed meson, D(2420), has been presented by the ARGUS group. Radiative UPSILON decay studies fail to confirm the zeta(8.3) and begin to place useful limits on Higgs bosons. First results from an experiment at Fermilab on low-background hadronic production of UPSILON states are shown. Accurate measurements of chi/sub b/(1P) masses by the ARGUS collaboration are noted, and interpreted as favoring scalar quark confinement. Studies of t and other heavy quarks will probe the q anti q interaction below 0.05 fm, are likely to be strongly affected by t anti t-Z interference, and can provide varied information on Higgs bosons. 144 refs., 21 figs

  5. Relativistic heavy ion physics

    International Nuclear Information System (INIS)

    Hill, J.C.; Wohn, F.K.

    1992-01-01

    In 1992 a proposal by the Iowa State University experimental nuclear physics group entitled ''Relativistic Heavy Ion Physics'' was funded by the US Department of Energy, Office of Energy Research, for a three-year period beginning November 15, 1991. This is a progress report for the first six months of that period but, in order to give a wider perspective, we report here on progress made since the beginning of calendar year 1991. In the first section, entitled ''Purpose and Trends,'' we give some background on the recent trends in our research program and its evolution from an emphasis on nuclear structure physics to its present emphasis on relativistic heavy ion and RHIC physics. The next section, entitled, ''Physics Research Programs,'' is divided into three parts. First, we discuss our participation in the program to develop a large detector named PHENIX for the RHIC accelerator. Second, we outline progress made in the study of electromagnetic dissociation (ED). A highlight of this endeavor is experiments carried out with the 197 Au beam from the AGS accelerator in April 1991. Third, we discuss progress in completion of our nuclear structure studies. In the final section a list of publications, invited talks and contributed talks starting in 1991 is given

  6. Actinides and heavy fermions

    International Nuclear Information System (INIS)

    Smith, J.L.; Fisk, Z.; Ott, H.R.

    1987-01-01

    The actinide series of elements begins with f-shell electrons forming energy bands, contributing to the bonding, and possessing no magnetic moments. At americium the series switches over to localized f electrons with magnetic moments. In metallic compounds this crossover of behavior can be modified and studied. In this continuum of behavior a few compounds on the very edge of localized f-electron behavior exhibit enormous electronic heat capacities at low temperatures. This is associated with an enhanced thermal mass of the conduction electrons, which is well over a hundred times the free electron mass, and is what led to the label heavy fermion for such compounds. A few of these become superconducting at even lower temperatures. The excitement in this field comes from attempting to understand how this heaviness arises and from the likelihood that the superconductivity is different from that of previously known superconductors. The effects of thorium impurities in UBe 13 were studied as a representative system for studying the nature of the superconductivity

  7. Heavy ion fusion

    International Nuclear Information System (INIS)

    Bock, R.

    1983-01-01

    Two accelerator scenarios for heavy ion fusion are considered as driver candidates for an ICF power plant: the RF linac with storage rings and the induction linac. The necessary beam intensity and beam quality requirements are already believed to be achievable in the long run; repetition rate and accelerator efficiency are not critical issues. Conceptual design studies have indicated that the technical problems of the ICF concept with a heavy ion driver can be solved and that the economical aspects are not prohibitive as compared to other ICF concepts. Nevertheless, many open problems still exist, and some new ones have exhibited themselves, and it has become evident that most of them cannot be investigated with existing facilities and at the present level of effort. The first section of this paper deals with current conceptual design studies and focuses on the interface between the accelerator and the reactor. The second section summarizes the present research programs and recommends that their scope should be expanded and intensified in the areas of accelerator physics and beam-target interaction and target physics. In the third section the author calls for a dedicated facility and reports on the plans and ideas for such a facility. Schematics of two proposed accelerator driver systems--the driver for HIBALL (5 MJ/pulse) and a single-pass four-beam induction linac (3 MJ/pulse)--are provided

  8. Heavy ion accelerating structure

    International Nuclear Information System (INIS)

    Pottier, Jacques.

    1977-01-01

    The heavy ion accelerating structure concerned in this invention is of the kind that have a resonance cavity inside which are located at least two longitudinal conducting supports electrically connected to the cavity by one of their ends in such a way that they are in quarter-wavelength resonance and in phase opposition. Slide tubes are electrically connected alternatively to one or the other of the two supports, they being electrically connected respectively to one or the other end of the side wall of the cavity. The feature of the structure is that it includes two pairs of supports symmetrically placed with respect to the centre line of the cavity, the supports of one pair fitted overhanging being placed symmetrically with respect to the centre line of the cavity, each slide tube being connected to the two supports of one pair. These support are connected to the slide wall of the cavity by an insulator located at their electrically free end. The accelerator structure composed of several structures placed end to end, the last one of which is fed by a high frequency field of adjustable amplitude and phase, enables a heavy ion linear accelerator to be built [fr

  9. Heavy flavours in ultra-relativistic heavy ions collisions

    International Nuclear Information System (INIS)

    Rosnet, Ph.

    2008-01-01

    The ultra-relativistic collisions of heavy ions are the today's only means to tackle in laboratory conditions the phase diagram in quantum chromodynamics and the strong interaction. The most recent theoretical studies predict a phase transition between the cold nuclear matter (a hadronic gas) and a plasma of quarks and gluons. Heavy flavour can characterize the nuclear matter produced in a heavy ion collision as well as its spatial-temporal evolution. Their study can be made through their decay into muons. The first part of this work presents the issue of ultra-relativistic heavy ion collisions and the role of heavy flavours. In the second part the author reviews the results of experiments performed at RHIC and particularly presents the analysis of the mass spectrum of dimuons in the Phenix experiment. The third part describes the muon trigger system of the Alice experiment at CERN and the expected performances for the study of di-muons

  10. Palaeoenvironmental changes in the Late Triassic (Rhaetian) of the Northern Calcareous Alps

    DEFF Research Database (Denmark)

    Mette, Wolfgang; Elsler, Armin; Korte, Christoph

    2012-01-01

    in the Kössen Formation and determine their significance for environmental and climatic conditions in the Rhaetian sea of the Eiberg Basin (Northern Calcareous Alps). For this purpose 60 δ 18O measurements on 43 articulate brachiopods samples from 8 different horizons were carried out. The results indicate...... to the lowest unit 3 of the Eiberg Member that parallels oxygen isotopes. This positive δ 13C trend is interrupted by a sudden ~1.5‰ negative excursion in the late Rhaetian (Late Rhaetian Event), a time span when the oxygen isotopes remain heavy....

  11. Heavy ion inertial fusion

    International Nuclear Information System (INIS)

    Keefe, D.; Sessler, A.M.

    1980-01-01

    Inertial fusion has not yet been as well explored as magnetic fusion but can offer certain advantages as an alternative source of electric energy for the future. Present experiments use high-power beams from lasers and light-ion diodes to compress the deuterium-tritium (D-T) pellets but these will probably be unsuitable for a power plant. A more promising method is to use intense heavy-ion beams from accelerator systems similar to those used for nuclear and high-energy physics; the present paper addresses itself to this alternative. As will be demonstrated the very high beam power needed poses new design questions, from the ion-source through the accelerating system, the beam transport system, to the final focus. These problems will require extensive study, both theoretically and experimentally, over the next several years before an optimum design for an inertial fusion driver can be arrived at. (Auth.)

  12. Relativistic heavy ion physics

    International Nuclear Information System (INIS)

    Hill, J.C.; Wohn, F.K.

    1993-01-01

    This is a progress report for the period May 1992 through April 1993. The first section, entitled ''Purpose and Trends, gives background on the recent trends in the research program and its evolution from an emphasis on nuclear structure physics to its present emphasis on relativistic heavy ion and RHIC physics. The next section, entitled ''Physics Research Progress'', is divided into four parts: participation in the program to develop a large detector named PHENIX for the RHIC accelerator; joining E864 at the AGS accelerator and the role in that experiment; progress made in the study of electromagnetic dissociation highlight of this endeavor is an experiment carried out with the 197 Au beam from the AGS accelerator in April 1992; progress in completion of the nuclear structure studies. In the final section a list of publications, invited talks, and contributed talks is given

  13. Heavy ion beam probing

    International Nuclear Information System (INIS)

    Hickok, R.L.

    1980-07-01

    This report consists of the notes distributed to the participants at the IEEE Mini-Course on Modern Plasma Diagnostics that was held in Madison, Wisconsin in May 1980. It presents an overview of Heavy Ion Beam Probing that briefly describes the principles and discuss the types of measurements that can be made. The problems associated with implementing beam probes are noted, possible variations are described, estimated costs of present day systems, and the scaling requirements for large plasma devices are presented. The final chapter illustrates typical results that have been obtained on a variety of plasma devices. No detailed calculations are included in the report, but a list of references that will provide more detailed information is included

  14. Heavy ion inertial fusion

    International Nuclear Information System (INIS)

    Keefe, D.; Sessler, A.M.

    1980-07-01

    Inertial fusion has not yet been as well explored as magnetic fusion but can offer certain advantages as an alternative source of electric energy for the future. Present experiments use high-power beams from lasers and light-ion diodes to compress the deuterium-tritium (D-T) pellets but these will probably be unsuitable for a power plant. A more promising method is to use intense heavy-ion beams from accelerator systems similar to those used for nuclear and high-energy physics; the present paper addresses itself to this alternative. As will be demonstrated the very high beam power needed poses new design questions, from the ion source through the accelerating system, the beam transport system, to the final focus. These problems will require extensive study, both theoretically and experimentally, over the next several years before an optimum design for an inertial fusion driver can be arrived at

  15. HEAVY ION LINEAR ACCELERATOR

    Science.gov (United States)

    Van Atta, C.M.; Beringer, R.; Smith, L.

    1959-01-01

    A linear accelerator of heavy ions is described. The basic contributions of the invention consist of a method and apparatus for obtaining high energy particles of an element with an increased charge-to-mass ratio. The method comprises the steps of ionizing the atoms of an element, accelerating the resultant ions to an energy substantially equal to one Mev per nucleon, stripping orbital electrons from the accelerated ions by passing the ions through a curtain of elemental vapor disposed transversely of the path of the ions to provide a second charge-to-mass ratio, and finally accelerating the resultant stripped ions to a final energy of at least ten Mev per nucleon.

  16. Heavy-ion superconducting linacs

    International Nuclear Information System (INIS)

    Delayen, J.R.

    1989-01-01

    This paper reviews the status of the superconducting heavy-ion accelerators. Most of them are linacs used as boosters for tandem electrostatic accelerators, although the technology is being extended to very low velocity to eliminate the need for an injector. The characteristics and features of the various superconducting heavy-ion accelerators are discussed. 45 refs

  17. Heavy-ion superconducting linacs

    Energy Technology Data Exchange (ETDEWEB)

    Delayen, J.R.

    1989-01-01

    This paper reviews the status of the superconducting heavy-ion accelerators. Most of them are linacs used as boosters for tandem electrostatic accelerators, although the technology is being extended to very low velocity to eliminate the need for an injector. The characteristics and features of the various superconducting heavy-ion accelerators are discussed. 45 refs.

  18. Heavy fermion and actinide materials

    International Nuclear Information System (INIS)

    1993-01-01

    During this period, 1/N expansions have been systematically applied to the calculation of the properties of highly correlated electron systems. These studies include examinations of (a) the class of materials known as heavy fermion semi-conductors, (b) the high energy spectra of heavy fermion systems, and (c) the doped oxide superconductors

  19. Heavy metals and soil microbes

    NARCIS (Netherlands)

    Giller, K.E.; Witter, E.; McGrath, S.

    2009-01-01

    The discovery in the early 1980s that soil microorganisms, and in particular the symbiotic bacteria Rhizobium, were highly sensitive to heavy metals initiated a new line of research. This has given us important insights into a range of topics: ecotoxicology, bioavailability of heavy metals, the role

  20. Heavy charged particle therapy

    International Nuclear Information System (INIS)

    Mizoe, Jun-etsu

    1995-01-01

    A pilot study of heavy charged particles with heavy ion medical accelerator in Chiba (HIMAC) for advanced H and N cancer has been carried out from June 1994 at National Institute of Radiological Sciences (NIRS). As of the beginning of August 1994, three patients were treated by 290 MeV carbon ions. The patients had adenocarcinoma of the cheek mucosa, squamous cell carcinoma of the ethmoid sinus and adenoid cystic carcinoma of the sublingual gland. Patients were immobilized by individual head coach and thermosplint facial shell. Individual collimators and bolus were also prepared for each ports. Dose fractionation for the initial pilot study group was 16.2 GyE/18 fractions/6 weeks, which would be equivalent to standard fractionation of 60.0 Gy/30 fractions/6 weeks with photons. This dose fractionation was considered to be 20% lesser than 75 GyE/37.5 fractions/7.5 weeks, which is estimated to be maximum tolerance dose for advanced H and N cancers. HIMAC worked well and there was no major trouble causing any treatment delay. Acute skin reactions of 3 patients were 2 cases of bright erythema with patchy moist desquamation and one of dull erythema, which were evaluated as equivalent reaction with irradiated dose. Acute mucosa reactions appeared to have lesser reaction than predicted mucositis. Tumor reactions of three patients were partial reaction (PR) at the end of treatment and nearly complete remission (CR) after 6 months of treatment. From October 1994, we started to treat patients with advanced H and N cancer with 10% high dose than previous dose. And new candidates of pilot study with non small cell lung cancer, brain tumor and carcinoma of the tongue were entered into pilot study. At the end of February 1995, a total of 21 patients were treated by carbon ions. (J.P.N.)

  1. Results of heavy ion radiotherapy

    International Nuclear Information System (INIS)

    Castro, J.R.

    1994-04-01

    The potential of heavy ion therapy for clinical use in cancer therapy stems from the biological parameters of heavy charged particles, and their precise dose localization. Biologically, carbon, neon and other heavy ion beams (up to about silicon) are clinically useful in overcoming the radioresistance of hypoxic tumors, thus increasing biological effectiveness relative to low-LET x-ray or electron beams. Cells irradiated by heavy ions show less variation in cell-cycle related radiosensitivity and decreased repair of radiation injury. The physical parameters of these heavy charged particles allow precise delivery of high radiation doses to tumors while minimizing irradiation of normal tissues. Clinical use requires close interaction between radiation oncologists, medical physicists, accelerator physicists, engineers, computer scientists and radiation biologists

  2. Heavy metal sorption by microalgae

    International Nuclear Information System (INIS)

    Sandau, E.; Sandau, P.; Pulz, O.

    1996-01-01

    Viable microalgae are known to be able to accumulate heavy metals (bioaccumulation). Against a background of the increasing environmental risks caused by heavy metals, the microalgae Chlorella vulgaris and Spirulina platensis and their potential for the biological removal of heavy metals from aqueous solutions were taken as an example for investigation. Small-scale cultivation tests (50 l) with Cd-resistant cells of Chlorella vulgaris have shown that approx. 40% of the added 10 mg Cd/l was removed from the solution within seven days. At this heavy metal concentration sensitive cells died. Non-viable microalgae are able to eliminate heavy metal ions in a short time by biosorption in uncomplicated systems, without any toxicity problems. Compared with original biomasses, the sorption capacity of microalgal by-products changes only insignificantly. Their low price makes them economical. (orig.)

  3. Late baryogenesis faces primordial nucleosynthesis

    International Nuclear Information System (INIS)

    Delbourgo-Salvador, P.; Audouze, J.; Salati, P.

    1991-11-01

    Since the sphalleron mechanism present in the standard theory of electro-weak interactions violates B+L, models have been suggested where baryogenesis takes place at late epochs and is concomitant with primordial nucleosynthesis. The possibility for the baryon asymmetry to be generated was numerically investigated at the same time as the light elements are cooked. The primordial yields of D, 3 He, 4 He and 7 Li were shown to exceed the upper limits inferred from observation, unless baryogenesis is anterior to the freeze-out of the weak interactions. This implies strong constraints on scenarios where the baryon asymmetry originates from the late decay of massive gravitinos. (author) 18 refs., 6 figs

  4. Late radiation pathology of mammals

    Energy Technology Data Exchange (ETDEWEB)

    Alexandrov, S N

    1982-01-01

    The comprehensive monograph on delayed radiation effects in mammals including man comprises 3 main chapters dealing with non-neoplastic as well as neoplastic manifestations of late radiation pathology, with the prophylaxis of delayed radiation effects, and with the therapy of radiation injuries. Alterations induced by whole-body irradiation and delayed radiation effects caused by partial body irradiation are described in detail. The developmental mechanisms and pathogenesis of non-neoplastic pathological changes and of radiation-induced neoplasms are elaborated.

  5. LATE NEUROSYPHILIS: TRENDS AND CHALLENGES.

    Directory of Open Access Journals (Sweden)

    Ivan Dimitrov

    2015-09-01

    Full Text Available Background: Syphilis is not only a disease of historical importance. It has been recognized that nowadays, in the era of AIDS, it still remains a serious challenge. For the last two decades there has been a resumption of neurosyphilis cases. This has revived the interest in the diagnostic and therapeutic challenges that the disease presents to clinical practice and to healthcare systems. Material/Methods: We present the overall picture of newly registered cases of syphilis in Varna municipality between 2009 and 2013, and report a case of neurosyphilis diagnosed at the first clinic of neurological diseases of St. Marina University Hospital during this period. Results: For the 5-year period, newly registered cases of syphilis in Varna have shown a tendency towards a decrease. Patients were typically in the early stages of the disease, primary and secondary. Late manifestations dropped from 29 in 2009 to 0 in 2010, but increased again to 15 in 2013. Only 1 case of neurosyphilis was registered during the 5-year period, in 2013. Conclusions: Neurological syndromes observed in cases of late neurosyphilis, presenting in different clinical forms, require a broad spectrum of differential diagnoses. Attention in everyday clinical practice should be focused on these cases which, though rare, are of high medical and social importance. Clinical cases of late neurosyphilis are often atypical and the early consideration of serologic tests or even biopsy may be of critical importance.

  6. The late-M dwarfs

    International Nuclear Information System (INIS)

    Bessell, M.S.

    1991-01-01

    Far-red spectra and VRIJHK photometry have been obtained for a sample of late-M dwarfs selected on the basis of large reduced red magnitudes from the LHS Catalog. Half of the stars in the three faintest 1 mag bins are late-M stars, the other red stars are metallic-hydride subdwarfs. Relations between various colors for the late-M dwarfs are investigated. Of all the colors I - K most reliably correlates with spectral type. FeH bands near 9900 A are clearly seen in the spectra of all dwarf stars later than M5. Two stars cooler than VB10, and similar in temperature to LHS2924 have been identified; both have H-alpha in emission and appear variable in magnitude and R - I color; one is a flare star. The other stars are of earlier spectral type and resemble W359 and VB8. The observed MI, I - K main sequence is in good agreement with the IG theoretical main sequence of Stringfellow, and the faintest stars could be about 0.09 solar mass red dwarfs or lower mass brown dwarfs. 65 refs

  7. Baryons in the heavy quark effective theory

    International Nuclear Information System (INIS)

    Mannel, T.; Roberts, W.; Ryzak, Z.

    1990-08-01

    We show how to incorporate baryons in the heavy quark effective theory. A convenient formalism is exhibited and applied to semileptonic weak decays of heavy baryons and to exclusive production of heavy baryons in e + e - annihilation. (orig.)

  8. Efficacy of fungicide combinations, phosphoric acid, and plant extract from stinging nettle on potato late blight management and tuber yield

    Science.gov (United States)

    Late blight, caused by Phytophthora infestans is a major constraint to potato production. Inadequate management of the disease has often resulted in heavy losses in various production regions. We assessed the efficacy of fungicides, phosphoric acid, and stinging nettle plant extract combinations for...

  9. THE PROPERTIES OF HEAVY ELEMENTS IN GIANT PLANET ENVELOPES

    Energy Technology Data Exchange (ETDEWEB)

    Soubiran, François; Militzer, Burkhard [Department of Earth and Planetary Science, University of California, Berkeley, CA 94720 (United States)

    2016-09-20

    The core-accretion model for giant planet formation suggests a two-layer picture for the initial structure of Jovian planets, with heavy elements in a dense core and a thick H–He envelope. Late planetesimal accretion and core erosion could potentially enrich the H–He envelope in heavy elements, which is supported by the threefold solar metallicity that was measured in Jupiter’s atmosphere by the Galileo entry probe. In order to reproduce the observed gravitational moments of Jupiter and Saturn, models for their interiors include heavy elements, Z , in various proportions. However, their effect on the equation of state of the hydrogen–helium mixtures has not been investigated beyond the ideal mixing approximation. In this article, we report results from ab initio simulations of fully interacting H–He– Z mixtures in order to characterize their equation of state and to analyze possible consequences for the interior structure and evolution of giant planets. Considering C, N, O, Si, Fe, MgO, and SiO{sub 2}, we show that the behavior of heavy elements in H–He mixtures may still be represented by an ideal mixture if the effective volumes and internal energies are chosen appropriately. In the case of oxygen, we also compute the effect on the entropy. We find the resulting changes in the temperature–pressure profile to be small. A homogeneous distribution of 2% oxygen by mass changes the temperature in Jupiter’s interior by only 80 K.

  10. Advanced technology heavy water monitors offering reduced implementation costs

    International Nuclear Information System (INIS)

    Kalechstein, W.; Hippola, K.B.

    1984-10-01

    The development of second generation heavy water monitors for use at CANDU power stations and heavy water plants has been completed and the instruments brought to the stage of commercial availability. Applications of advanced technology and reduced utilization of custom manufactured components have together resulted in instruments that are less expensive to produce than the original monitors and do not require costly station services. The design has been tested on two prototypes and fully documented, including the inspection and test procedures required for manufacture to the CSA Z299.3 quality verfication program standard. Production of the new monitors by a commercial vendor (Barringer Research Ltd.) has begun and the first instrument is scheduled for delivery to CRNL's NRU reactor in late 1984

  11. Late Effects of Polio: An Overview

    Science.gov (United States)

    ... Polio Wellness Retreats For Health Professionals The Late Effects of Polio: An Overview FRENCH | GERMAN | PORTUGUESE POLIOMYELITIS ( ... largest and most inclusive category is called Late Effects of Polio or Polio Sequelae and is defined ...

  12. Toxicity of heavy metals in the environment

    National Research Council Canada - National Science Library

    Oehme, F.W

    1978-01-01

    ... as the fundamental mechanisms of toxicity resulting from heavy metal chemicals. The more common toxic heavy metals, along with their biochemistry and associated clinical syndromes, are then described...

  13. From heavy nuclei to super-heavy nuclei

    International Nuclear Information System (INIS)

    Theisen, Ch.

    2003-01-01

    The existence of super-heavy nuclei has been predicted nearly fifty years ago. Due to the strong coulomb repulsion, the stabilisation of these nuclei is possible only through shell effects. The reasons for this fragile stability, as well as the theoretical predictions concerning the position of the island of stability are presented in the first part of this lecture. In the second part, experiments and experimental techniques which have been used to synthesize or search for super-heavy elements are described. Spectroscopic studies performed in very heavy elements are presented in the following section. We close this lecture with techniques that are currently being developed in order to reach the superheavy island and to study the structure of very-heavy nuclei. (author)

  14. Heavy Water - Industrial Separation Processes

    International Nuclear Information System (INIS)

    Peculea, M.

    1984-01-01

    This monograph devoted to the heavy water production mainly presents the Romanian experience in the field which started in early sixties from the laboratory scale production and reached now the level of large scale industrial production at ROMAG-Drobeta, Romania. The book is structured in eleven chapters entitled: Overview, The main physical properties, Sources, Uses, Separation factor and equilibrium constant, Mathematical modelling of the separation process, Thermodynamical considerations on the isotope separation, Selection criteria for heavy water separation processes, Industrial installations for heavy water production, Prospects, Acknowledgements. 200 Figs., 90 Tabs., 135 Refs

  15. Heavy quark fragmentation functions in the heavy quark effective theory

    International Nuclear Information System (INIS)

    Martynenko, A.P.; Saleev, V.A.

    1996-01-01

    The fragmentation of b-bar-antiquark into polarized B c * -mesons and b-quark into P-wave (c-bar b) states in the Heavy Quark Effective Theory. The heavy quark fragmentation functions in longitudinally and transversely polarized S-wave b-bar c-states and P-wave mesons containing b-, c-quarks also, with the exact account of corrections of first order in 1/m b . 20 refs., 2 figs

  16. Heavy-element nucleosynthesis

    International Nuclear Information System (INIS)

    Mathews, G.J.

    1990-01-01

    New measurements and theoretical studies of nuclear properties, together with new astronomical data on the growth of heavy-element abundances during the early history of the Galaxy, now provide a clearer picture of where in nature the elements heavier than iron are produced by rapid (r-process) and show (s-process) neutron capture reactions. The nuclear data suggest that the r-process involves a high-neutron-density beta-flow equilibrium environment and that the s-process may have occurred at a temperature and neutron density consistent with a 13 C(α,n) 16 0 neutron source. The astronomical data, when compared with simple galactic chemical evolution modes, suggests that the r-process is associated with type II supernovae and that the neutron source must be manufactured by the star. Low-mass type II supernovae are proposed as the most important contributors to the r-process. A 13 C neutron source in intermediate-mass stars is proposed for the s-process. 64 refs., 7 figs

  17. Heavy ion fusion sources

    International Nuclear Information System (INIS)

    Grote, D.P.; Kwan, J.; Westenskow, G.

    2003-01-01

    In Heavy-Fusion and in other applications, there is a need for high brightness sources with both high current and low emittance. The traditional design with a single monolithic source, while very successful, has significant constraints on it when going to higher currents. With the Child-Langmuir current-density limit, geometric aberration limits, and voltage breakdown limits, the area of the source becomes a high power of the current, A ∼ I 8/3 . We are examining a multi-beamlet source, avoiding the constraints by having many beamlets each with low current and small area. The beamlets are created and initially accelerated separately and then merged to form a single beam. This design offers a number of potential advantages over a monolithic source, such as a smaller transverse footprint, more control over the shaping and aiming of the beam, and more flexibility in the choice of ion sources. A potential drawback, however, is the emittance that results from the merging of the beamlets. We have designed injectors using simulation that have acceptably low emittance and are beginning to examine them experimentally

  18. Heavy fields and gravity

    Energy Technology Data Exchange (ETDEWEB)

    Goon, Garrett [Institute of Physics, Universiteit van Amsterdam,Science Park 904, Amsterdam, 1090 GL (Netherlands)

    2017-01-11

    We study the effects of heavy fields on 4D spacetimes with flat, de Sitter and anti-de Sitter asymptotics. At low energies, matter generates specific, calculable higher derivative corrections to the GR action which perturbatively alter the Schwarzschild-(A)dS family of solutions. The effects of massive scalars, Dirac spinors and gauge fields are each considered. The six-derivative operators they produce, such as ∼R{sup 3} terms, generate the leading corrections. The induced changes to horizon radii, Hawking temperatures and entropies are found. Modifications to the energy of large AdS black holes are derived by imposing the first law. An explicit demonstration of the replica trick is provided, as it is used to derive black hole and cosmological horizon entropies. Considering entropy bounds, it’s found that scalars and fermions increase the entropy one can store inside a region bounded by a sphere of fixed size, but vectors lead to a decrease, oddly. We also demonstrate, however, that many of the corrections fall below the resolving power of the effective field theory and are therefore untrustworthy. Defining properties of black holes, such as the horizon area and Hawking temperature, prove to be remarkably robust against higher derivative gravitational corrections.

  19. Heavy ion elastic scatterings

    International Nuclear Information System (INIS)

    Mermaz, M.C.

    1984-01-01

    Diffraction and refraction play an important role in particle elastic scattering. The optical model treats correctly and simultaneously both phenomena but without disentangling them. Semi-classical discussions in terms of trajectories emphasize the refractive aspect due to the real part of the optical potential. The separation due to to R.C. Fuller of the quantal cross section into two components coming from opposite side of the target nucleus allows to understand better the refractive phenomenon and the origin of the observed oscillations in the elastic scattering angular distributions. We shall see that the real part of the potential is responsible of a Coulomb and a nuclear rainbow which allows to determine better the nuclear potential in the interior region near the nuclear surface since the volume absorption eliminates any effect of the real part of the potential for the internal partial scattering waves. Resonance phenomena seen in heavy ion scattering will be discussed in terms of optical model potential and Regge pole analysis. Compound nucleus resonances or quasi-molecular states can be indeed the more correct and fundamental alternative

  20. Relativistic heavy ion research

    International Nuclear Information System (INIS)

    1992-01-01

    Experimental work is reported on the following topics: transverse energy production in 10.7-GeV/c/u Au on Au collisions; first results on delta ray production and charged particle multiplicities with the Au beam at 10.7 GeV/c/A; preliminary studies on the feasibility of flow measurement with the E814 participant calorimeter; preliminary results from the E877 telescope; and low-p t baryon distribution in Si+Al, Pb collisions at the AGS. Then the status of the Hadronic Calorimeter project of AGS Experiment E864 (ECOS--Exotic Composite Object Spectrometer) is reviewed. Next, the same is done for work of the STAR RHIC collaboration (Silicon Vertex Tracker (SVT) project evolution and development in FY92, SVT software results from 1992, SVT instrumentation, FY93 SVT pion test beam). The instrumentation section deals with the design and installation of a target rapidity telescope for BNL experiment 814/877 and a repair scheme for the E814/E877 participant calorimeter. Finally, the theory part addresses bosonic kinetics: thermalization of mesons and the pion p perpendicular spectrum in ultrarelativistic heavy-ion collisions and non-equilibrium properties of hadronic mixtures

  1. Heavy quarks and leptons

    International Nuclear Information System (INIS)

    Azimov, Ya.I.; Khoze, V.A.

    1979-01-01

    Experimental results which proved the reality of quarks are reviewed along with further experiments broadening the representation of quarks and leptons and providing the basis to develop the theory of elementary particles. The discovery of the J/psi particle is noted to give rise to the discovery of c-quark, the existance of which is confirmed by the discovery of charmed hadrons. The main aspects of quantum chromodynamics explaining the mechanism of strong interaction of quarks are considered along with those of the Weinberg-Salam theory proposed to describe weak and electromagnetic interactions of quarks and leptons. Experimental data testifying to the existance of heavy tausup(+-) leptons are presented. The history of discovery of γ mesons and of a new heavier b-quark is described. Perspectives for studying elementary particles are discussed. Further studies of γ mesons, discovery and investigation of charmed particles are noted to be immediate tasks along with the search for manifestation of t-quark considered to be a partner of b-quark from the viewpoint of the Weinberg-Salam model

  2. Heavy particle effects

    International Nuclear Information System (INIS)

    Yao, Y.P.

    1981-01-01

    There are two problems discussed, both of which have to do with dissimilar magnitudes in mass. Theoretically, we can devise the large difference in mass as observed by decreeing some vev, v/sub i/ to be much bigger than the other; or, we can assume that some couplings g/sub i/ are much stronger. These two different assumptions give rise to entirely different patterns of interaction in the resulting theory. The first way to generate a mass hierarchy can be called the soft way, because in the zeroth order, the large mass scale leaves its foot print merely in a few effective parameters of the residual theory. The effective theory is renormalizable, sans anomaly. In this limit, the heavy particles decouple. The second assumption (g/sub j/ much greater than g/sub j'/) to create mass hierarchy does a lot of violence to a theory. Effects of the large mass scale will be felt by the system left behind in many ways. An infinite number of parameters are needed to summarize the effects in this limit. This is called the hard limit. It follows that the resulting effective Lagrangian, if in fact it makes sense to construct one at all, will be non-polynomial and apparently non-renormalizable

  3. Late prematurity: a systematic review

    Directory of Open Access Journals (Sweden)

    Luís Carlos Machado, Júnior

    2014-05-01

    Full Text Available Objective: this study aimed to review the literature regarding late preterm births (34 weeks to 36 weeks and 6 days of gestation in its several aspects. Sources: the MEDLINE, LILACS, and Cochrane Library databases were searched, and the references of the articles retrieved were also used, with no limit of time. Data synthesis: numerous studies showed a recent increase in late preterm births. In all series, late preterm comprised the majority of preterm births. Studies including millions of births showed a strong association between late preterm birth and neonatal mortality. A higher mortality in childhood and among young adults was also observed. Many studies found an association with several neonatal complications, and also with long-term disorders and sequelae: breastfeeding problems, cerebral palsy, asthma in childhood, poor school performance, schizophrenia, and young adult diabetes. Some authors propose strategies to reduce late preterm birth, or to improve neonatal outcome: use of antenatal corticosteroids, changes in some of the guidelines for early delivery in high-risk pregnancies, and changes in neonatal care for this group. Conclusions: numerous studies show greater mortality and morbidity in late preterm infants compared with term infants, in addition to long-term disorders. More recent studies evaluated strategies to improve the outcomes of these neonates. Further studies on these strategies are needed. Resumo: Objetivo: revisar a literatura sobre prematuridade tardia (nascimentos de 34 semanas a 36 semanas e seis dias em seus vários aspectos. Fonte dos dados: buscas nas bases MEDLINE, LILACS e Biblioteca Cochrane, sem limite de tempo, e nas referências bibliográficas dos artigos encontrados. Síntese dos dados: muitos estudos mostram aumento na taxa de prematuridade tardia nos últimos anos. Em todas as séries, os prematuros tardios correspondem à maioria dos nascimentos prematuros. Estudos envolvendo análises de milhões de

  4. Heavy Flavor Production in Heavy Ion Collisions at CMS

    CERN Document Server

    Sun, Jian

    2016-01-01

    Studies of Heavy flavor production are of great interest in heavy ion collisions. In the produced medium, the binding potential between a quark and antiquark in quarkonium is screened by surrounding light quarks and antiquarks. Thus, the various quarkonium states are expected to be melt at different temperatures depending on their binding energies, which allows us to characterize the QCD phase transition. In addition, open heavy flavor production are relevant for flavor-dependence of the in-medium parton energy loss. In QCD, gluons are expected to lose more energy compared to quarks when passing through the QGP due to the larger color charge. Compared to light quarks, heavy quarks are expected to lose less radiative energy because gluon radiation is suppressed at angles smaller than the ratio of the quark mass to its energy. This dead cone effect (and its disappearance at high transverse momentum) can be studied using open heavy flavor mesons and heavy flavor tagged jets. With CMS detector, quarkonia, open he...

  5. Heavy quark and magnetic moment

    International Nuclear Information System (INIS)

    Mubarak, Ahmad; Jallu, M.S.

    1979-01-01

    The magnetic moments and transition moments of heavy hadrons including the conventional particles are obtained under the SU(5) truth symmetry scheme. To this end state vectors are defined and the quark additivity principle is taken into account. (author)

  6. Heavy flavour production at LHCb

    CERN Document Server

    Barsuk, Sergey

    2016-01-01

    The present write-up reports recent LHCb results on production of quarkonium and open flavour states, as well as selected results on associated production, central exclusive production and pro- duction in heavy ion collisions.

  7. Principles of heavy oil recovery

    Energy Technology Data Exchange (ETDEWEB)

    Szasz, S.E.; Thomas, G.W.

    1965-10-01

    Rising exploration costs have prompted greater interest in the large known deposits of heavy oil in North America. Because of high oil viscosities in such reservoirs, recoveries are poor, fluid drives are inefficient and production rates are uneconomical. Viscosity reduction can best be accomplished by heating the reservoir. The basic aspects of reservoir heating are reviewed and those processes which are of practical importance in heavy oil reservoirs are discussed. Wellbore heating frequently can be applied to heavy oil reservoirs to increase production rates. In hot waterflooding, the water requirements are much higher than an ordinary waterflood. Steam floods are more attractive, but operating costs are generally high. Conduction heating processes appear most promising. Among these is included the cyclic steam-soak process. A simple method is presented for estimating the performance from the first cycle of steam injection into the formation, assuming gravity as the only driving energy. An example calculation for a typical heavy oil reservoir is given. (26 refs.)

  8. The Canadian heavy water situation

    International Nuclear Information System (INIS)

    Dahlinger, A.

    The Canadian heavy water industry is analyzed. Supply and demand are predicted through 1985. Pricing is broken down into components. Backup R and D contributes greatly to process improvements. (E.C.B.)

  9. Heavy quark spectroscopy and decay

    International Nuclear Information System (INIS)

    Schindler, R.H.

    1987-01-01

    The understanding of q anti q systems containing heavy, charmed, and bottom quarks has progressed rapidly in recent years, through steady improvements in experimental techniques for production and detection of their decays. These lectures are meant to be an experimentalist's review of the subject. In the first of two lectures, the existing data on the spectroscopy of the bound c anti c and b anti b systems will be discussed. Emphasis is placed on comparisons with the theoretical models. The second lecture covers the rapidly changing subject of the decays of heavy mesons (c anti q and b anti q), and their excited states. In combination, the spectroscopy and decays of heavy quarks are shown to provide interesting insights into both the strong and electroweak interactions of the heavy quarks. 103 refs., 39 figs

  10. Exotic heavy baryons at LHC

    International Nuclear Information System (INIS)

    Biro, T.S.; Zimanyi, J.

    1993-06-01

    A heavy bottom-charm six-quark baryon is considered. A semiclassical and a Gaussian estimate show that the octet-octet bbb-ccc configuration can be favoured energetically rather than the singlet-singlet one. This result suggests that a confined bbb-ccc six-quark state may exist. Such objects may be produced in suitable amounts by heavy-ion collisions at Large Hadronic Collider energies. (R.P.) 8 refs. 1 fig

  11. Heavy leptons at hadron colliders

    International Nuclear Information System (INIS)

    Ohnemus, J.E.

    1987-01-01

    The recent advent of high energy hadron colliders capable of producing weak bosons has opened new vistas for particle physics research, including the search for a possible fourth generation heavy charged lepton, which is the primary topic of the thesis. Signals for identifying a new heavy lepton have been calculated and compared to Standard Model backgrounds. Results are presented for signals at the CERN collider, the Fermilab collider, and the proposed Superconducting Supercollider

  12. Heavy Ion Physics at LHC

    CERN Document Server

    Valenti, G.

    2002-01-01

    The study of heavy ion interactions constitutes an important part of the experimental program outlined for the Large Hadron Collider under construction at CERN and expected to be operational by 2006. ALICE 1 is the single detector having the capabilities to explore at the same time most of the characteristics of high energy heavy ion interactions. Specific studies of jet quenching and quarkonia production, essentially related to µ detection are also planned by CMS 2 .

  13. BNL heavy ion fusion program

    International Nuclear Information System (INIS)

    Maschke, A.W.

    1978-01-01

    A principal attraction of heavy ion fusion is that existing accelerator technology and theory are sufficiently advanced to allow one to commence the design of a machine capable of igniting thermonuclear explosions. There are, however, a number of features which are not found in existing accelerators built for other purposes. The main thrust of the BNL Heavy Ion Fusion program has been to explore these features. Longitudinal beam bunching, very low velocity acceleration, and space charge neutralization are briefly discussed

  14. The Canadian heavy water situation

    International Nuclear Information System (INIS)

    Dahlinger, A.

    1975-08-01

    Existing heavy water plants in Canada are producing at a satisfactory rate and currently planned capacity is in balance with projected needs. By 1980, we shall have Girdler-Sulphide plants installed with a design capacity of almost 600 kg/h. Effort is required to minimize production costs for heavy water and to ensure that costs do not increase faster than the current inflationary trend. (Author)

  15. Phenomenology of heavy quark systems

    International Nuclear Information System (INIS)

    Gilman, F.J.

    1987-03-01

    The spectroscopy of heavy quark systems is examined with regards to spin independent and spin dependent potentials. It is shown that a qualitative picture exists of the spin-independent forces, and that a semi-quantitative understanding exists for the spin-dependent effects. A brief review is then given of the subject of the decays of hadrons containing heavy quarks, including weak decays at the quark level, and describing corrections to the spectator model

  16. Heavy ion medical accelerator, HIMAC

    International Nuclear Information System (INIS)

    Yamada, Satoru

    1993-01-01

    The heavy ion beam is undoutedly suitable for the cancer treatment. The supriority of the heavy ions over the conventional radiations including protons and neutrons comes mainly from physical characteristics of a heavy particle with multiple charges. A straggling angle due to a multiple Coulomb scattering process in a human body is small for heavy ions, and the small scattering angle results in a good dose localization in a transverse direction. An ionization ratio of the heavy ion beam makes a very sharp peak at the ends of their range. The height of the peak is higher for the heavier ions and shows excellent biomedical effects around Ne ions. In order to apply heavy ion beams to cancer treatment, Heavy Ion Medical Accelerator in Chiba (HIMAC) has been constructed at National Institute of Radiological Sciences. The accelerator complex consists of two ion sources, two successive linac tanks, a pair of synchrotron rings, a beam transport system and an irradiation system. An operation frequency is 100 MHz for two linacs, and the ion energy is 6.0 MeV/u at the output end of the linac. The other four experimental rooms are prepared for basic experiments. The synchrotron accelerates ions up to 800 MeV/u for a charge to mass ratio of 1/2. The long beam transport line provides two vertical beams in addition with two horizontal beams for the treatment. The three treatment rooms are prepared one of which is equipped with both horizontal and vertical beam lines. The whole facility will be open for all scientists who have interests in the heavy ion science as well as the biophysics. The conceptual design study of HIMAC started in 1984, and the construction of the accelerator complex was begun in March 1988. The beam acceleration tests of the injector system was successfully completed in March of this year, and tests of the whole system will be finished throughout this fyscal year. (author)

  17. Status of Heavy Neutrino Experiments

    CERN Document Server

    Wynne, Benjamin; The ATLAS collaboration

    2017-01-01

    The observation of neutrino oscillations raises the possibility that there exist additional, undiscovered high-mass neutrinos, giving mass to Standard Model neutrinos via the seesaw mechanism. By pushing the collider energy frontier at the LHC, the possibility arises that these heavy neutrinos may be produced and identified. We summarise the latest LHC results of searches for heavy neutrinos in a variety of final states.

  18. The heavy quark expansion of QCD

    International Nuclear Information System (INIS)

    Falk, A.F.

    1997-01-01

    These lectures contain an elementary introduction to heavy quark symmetry and the heavy quark expansion. Applications such as the expansion of heavy meson decay constants and the treatment of inclusive and exclusive semileptonic B decays are included. Heavy hadron production via nonperturbative fragmentation processes is also discussed. 54 refs., 7 figs

  19. The heavy quark expansion of QCD

    Energy Technology Data Exchange (ETDEWEB)

    Falk, A.F. [Johns Hopkins Univ., Baltimore, MD (United States). Dept. of Physics and Astronomy

    1997-06-01

    These lectures contain an elementary introduction to heavy quark symmetry and the heavy quark expansion. Applications such as the expansion of heavy meson decay constants and the treatment of inclusive and exclusive semileptonic B decays are included. Heavy hadron production via nonperturbative fragmentation processes is also discussed. 54 refs., 7 figs.

  20. Heavy Flavor Physics in Heavy-Ion Collisions with STAR Heavy Flavor Tracker

    International Nuclear Information System (INIS)

    Yifei Zhang

    2010-01-01

    Heavy quarks are a unique tool to probe the strongly interacting matter created in relativistic heavy-ion collisions at RHIC energies. Due to their large mass, energetic heavy quarks are predicted to lose less energy than light quarks by gluon radiation when they traverse a Quark-Gluon Plasma. In contrast, recent measurements of non-photonic electrons from heavy quark decays at high transverse momentum (p T ) show a jet quenching level similar to that of the light hadrons. Heavy quark are produced mainly at early stage in heavy-ion collisions, thus they are proposed to probe the QCD medium and to be sensitive to bulk medium properties. Ultimately, their flow behavior may help establish whether light quarks thermalize. But due to the absence of the measurement of B-mesons and precise measurement of D-mesons, it is difficult to separate bottom and charm contributions experimentally in current non-photonic electron measurements for both spectra and elliptic flow v 2 . Therefore, topological reconstruction of D-mesons and identification of electrons from charm and bottom decays are crucial to understand the heavy flavor production and their in medium properties. The Heavy Flavor Tracker (HFT) is a micro-vertex detector utilizing active pixel sensors and silicon strip technology. The HFT will significantly extend the physics reach of the STAR experiment for precise measurement of charmed and bottom hadrons. We present a study on the open charm nuclear modification factor, elliptic flow v 2 and λ c measurement as well as the measurement of bottom mesons via a semi-leptonic decay. (author)

  1. You can't "nudge" nuggets: An investigation of college late-night dining with behavioral economics interventions.

    Science.gov (United States)

    Bevet, Samuel; Niles, Meredith T; Pope, Lizzy

    2018-01-01

    A mixed-methods approach was used to evaluate and improve the "late-night dining" options in a university dining hall. Surveys assessed student desires for late-night offerings, and evaluated students' habits and motivations during late-night dining. Two interventions were implemented to see if students could be "nudged" into different choice patterns. In the first, a "veggie-heavy" entrée was added at the beginning of the entrée line, so that students would substitute an entrée containing vegetables for the alternatives. In the second, a snack-food bar was set up to cater to students who didn't want to stand in the long entrée line, and preferred a snack. Data on food choice was collected during the interventions. Survey responses showed significant differences in the reasons females and males utilized late-night dining (p<0.001). We also found that students at late-night dining had a lower emphasis on health than the general student population. Even students at late-night who reported being health-conscious showed no difference in food selections from students who said health was not important (p = 0.883). Veggie-heavy entrées had mild success in increasing vegetable selection. However, veggie-heavy entrées were largely ignored when the other option was chicken nuggets. The snack bar was very popular. Entrée placement and convenience lines may have mild impacts on food selection in a late-night dining environment.

  2. Suppression and Two-Particle Correlations of Heavy Mesons in Heavy-Ion Collisions

    Energy Technology Data Exchange (ETDEWEB)

    Cao, Shanshan [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Qin, Guang-You [Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University, Wuhan, 430079 (China); Bass, Steffen A. [Department of Physics, Duke University, Durham, NC 27708 (United States)

    2016-12-15

    We study the medium modification of heavy quarks produced in heavy-ion collisions. The evolution of heavy quarks inside the QGP is described using a modified Langevin framework that simultaneously incorporates their collisional and radiative energy loss. Within this framework, we provide good descriptions of the heavy meson suppression and predictions for the two-particle correlation functions of heavy meson pairs.

  3. 3.6 AND 4.5 μm PHASE CURVES AND EVIDENCE FOR NON-EQUILIBRIUM CHEMISTRY IN THE ATMOSPHERE OF EXTRASOLAR PLANET HD 189733b

    International Nuclear Information System (INIS)

    Knutson, Heather A.; Lewis, Nikole; Showman, Adam P.; Fortney, Jonathan J.; Laughlin, Gregory; Burrows, Adam; Cowan, Nicolas B.; Agol, Eric; Aigrain, Suzanne; Charbonneau, David; Désert, Jean-Michel; Deming, Drake; Henry, Gregory W.; Langton, Jonathan

    2012-01-01

    We present new, full-orbit observations of the infrared phase variations of the canonical hot Jupiter HD 189733b obtained in the 3.6 and 4.5 μm bands using the Spitzer Space Telescope. When combined with previous phase curve observations at 8.0 and 24 μm, these data allow us to characterize the exoplanet's emission spectrum as a function of planetary longitude and to search for local variations in its vertical thermal profile and atmospheric composition. We utilize an improved method for removing the effects of intrapixel sensitivity variations and robustly extracting phase curve signals from these data, and we calculate our best-fit parameters and uncertainties using a wavelet-based Markov Chain Monte Carlo analysis that accounts for the presence of time-correlated noise in our data. We measure a phase curve amplitude of 0.1242% ± 0.0061% in the 3.6 μm band and 0.0982% ± 0.0089% in the 4.5 μm band, corresponding to brightness temperature contrasts of 503 ± 21 K and 264 ± 24 K, respectively. We find that the times of minimum and maximum flux occur several hours earlier than predicted for an atmosphere in radiative equilibrium, consistent with the eastward advection of gas by an equatorial super-rotating jet. The locations of the flux minima in our new data differ from our previous observations at 8 μm, and we present new evidence indicating that the flux minimum observed in the 8 μm is likely caused by an overshooting effect in the 8 μm array. We obtain improved estimates for HD 189733b's dayside planet-star flux ratio of 0.1466% ± 0.0040% in the 3.6 μm band and 0.1787% ± 0.0038% in the 4.5 μm band, corresponding to brightness temperatures of 1328 ± 11 K and 1192 ± 9 K, respectively; these are the most accurate secondary eclipse depths obtained to date for an extrasolar planet. We compare our new dayside and nightside spectra for HD 189733b to the predictions of one-dimensional radiative transfer models from Burrows et al. and conclude that fits to

  4. 3.6 AND 4.5 {mu}m PHASE CURVES AND EVIDENCE FOR NON-EQUILIBRIUM CHEMISTRY IN THE ATMOSPHERE OF EXTRASOLAR PLANET HD 189733b

    Energy Technology Data Exchange (ETDEWEB)

    Knutson, Heather A. [Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 (United States); Lewis, Nikole; Showman, Adam P. [Department of Planetary Sciences and Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721 (United States); Fortney, Jonathan J.; Laughlin, Gregory [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Burrows, Adam [Department of Astrophysical Sciences, Princeton University, Princeton, NJ 08544 (United States); Cowan, Nicolas B. [CIERA, Northwestern University, Evanston, IL 60208 (United States); Agol, Eric [Department of Astronomy, University of Washington, Seattle, WA 98195 (United States); Aigrain, Suzanne [Sub-department of Astrophysics, Department of Physics, University of Oxford, Oxford OX1 3RH (United Kingdom); Charbonneau, David; Desert, Jean-Michel [Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States); Deming, Drake [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); Henry, Gregory W. [Center of Excellence in Information Systems, Tennessee State University, 3500 John A. Merritt Blvd., Box 9501, Nashville, TN 37209 (United States); Langton, Jonathan, E-mail: hknutson@caltech.edu [Department of Physics, Principia College, 1 Maybeck Place, Elsah, IL 62028 (United States)

    2012-07-20

    We present new, full-orbit observations of the infrared phase variations of the canonical hot Jupiter HD 189733b obtained in the 3.6 and 4.5 {mu}m bands using the Spitzer Space Telescope. When combined with previous phase curve observations at 8.0 and 24 {mu}m, these data allow us to characterize the exoplanet's emission spectrum as a function of planetary longitude and to search for local variations in its vertical thermal profile and atmospheric composition. We utilize an improved method for removing the effects of intrapixel sensitivity variations and robustly extracting phase curve signals from these data, and we calculate our best-fit parameters and uncertainties using a wavelet-based Markov Chain Monte Carlo analysis that accounts for the presence of time-correlated noise in our data. We measure a phase curve amplitude of 0.1242% {+-} 0.0061% in the 3.6 {mu}m band and 0.0982% {+-} 0.0089% in the 4.5 {mu}m band, corresponding to brightness temperature contrasts of 503 {+-} 21 K and 264 {+-} 24 K, respectively. We find that the times of minimum and maximum flux occur several hours earlier than predicted for an atmosphere in radiative equilibrium, consistent with the eastward advection of gas by an equatorial super-rotating jet. The locations of the flux minima in our new data differ from our previous observations at 8 {mu}m, and we present new evidence indicating that the flux minimum observed in the 8 {mu}m is likely caused by an overshooting effect in the 8 {mu}m array. We obtain improved estimates for HD 189733b's dayside planet-star flux ratio of 0.1466% {+-} 0.0040% in the 3.6 {mu}m band and 0.1787% {+-} 0.0038% in the 4.5 {mu}m band, corresponding to brightness temperatures of 1328 {+-} 11 K and 1192 {+-} 9 K, respectively; these are the most accurate secondary eclipse depths obtained to date for an extrasolar planet. We compare our new dayside and nightside spectra for HD 189733b to the predictions of one-dimensional radiative transfer models

  5. Antibiotics in late clinical development.

    Science.gov (United States)

    Fernandes, Prabhavathi; Martens, Evan

    2017-06-01

    Most pharmaceutical companies have stopped or have severely limited investments to discover and develop new antibiotics to treat the increasing prevalence of infections caused by multi-drug resistant bacteria, because the return on investment has been mostly negative for antibiotics that received marketing approved in the last few decades. In contrast, a few small companies have taken on this challenge and are developing new antibiotics. This review describes those antibiotics in late-stage clinical development. Most of them belong to existing antibiotic classes and a few with a narrow spectrum of activity are novel compounds directed against novel targets. The reasons for some of the past failures to find new molecules and a path forward to help attract investments to fund discovery of new antibiotics are described. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  6. Heavy quark photoproduction in ultraperipheral heavy ion collisions

    International Nuclear Information System (INIS)

    Klein, Spencer R.; Nystrand, Joakim; Vogt, Ramona

    2002-01-01

    Heavy quarks are copiously produced in ultraperipheral heavy ion collisions. In the strong electromagnetic fields, cc-bar and bb-bar are produced by photonuclear and two-photon interactions. Hadroproduction can also occur in grazing interactions. We calculate the total cross sections and the quark transverse momentum and rapidity distributions, as well as the QQ-bar invariant mass spectra from the three production channels. We consider AA and pA collisions at the Relativistic Heavy Ion Collider and the Large Hadron Collider. We discuss techniques for separating the three processes and describe how the AA to pA production ratios might be measured accurately enough to study nuclear shadowing

  7. Argonne superconducting heavy-ion linac

    International Nuclear Information System (INIS)

    Bollinger, L.M.; Benaroya, R.; Clifft, B.E.; Jaffey, A.H.; Johnson, K.W.; Khoe, T.K.; Scheibelhut, C.H.; Shepard, K.W.; Wangler, Y.Z.

    1976-01-01

    A summary is given of the status of a project to develop and build a small superconducting linac to boost the energy of heavy ions from an existing tandem electrostatic accelerator. The design of the system is well advanced, and construction of major components is expected to start in late 1976. The linac will consist of independently-phased resonators of the split-ring type made of niobium and operating at a temperature of 4.2 0 K. The resonance frequency is 97 MHz. Tests on full-scale resonators lead one to expect accelerating fields of approximately 4 MV/m within the resonators. The linac will be long enough to provide a voltage gain of at least 13.5 MV, which will allow ions with A less than or approximately 80 to be accelerated above the Coulomb barrier of any target. The modular nature of the system will make future additions to the length relatively easy. A major design objective is to preserve the good quality of the tandem beam. This requires an exceedingly narrow beam pulse, which is achieved by bunching both before and after the tandem. Focusing by means of superconducting solenoids within the linac limit the radial size of the beam. An accelerating structure some 15 meters downstream from the linac will manipulate the longitudinal phase ellipse so as to provide the experimenter with either very good energy resolution (ΔE/E approximately equal to 2 x 10 -4 ) or very good time resolution

  8. Heavy ion fusion- Using heavy ions to make electricity

    International Nuclear Information System (INIS)

    Celata, C.M.

    2004-01-01

    The idea of using nuclear fusion as a source of commercial electrical power has been pursued worldwide since the 1950s. Two approaches, using magnetic and inertial confinement of the reactants, are under study. This paper describes the difference between the two approaches, and discusses in more detail the heavy-ion-driven inertial fusion concept. A multibeam induction linear accelerator would be used to bring ∼100 heavy ion beams to a few GeV. The beams would then heat and compress a target of solid D-T. This approach is unique among fusion concepts in its ability to protect the reaction chamber wall from neutrons and debris

  9. Late Onset Bipolar Disorder: Case Report

    OpenAIRE

    Filipa Araújo; Adriana Horta

    2016-01-01

    Background: Bipolar disorder affects approximately 1% of the population, with diagnosis often being made during late adolescence and early adulthood, and only rarely (0.1%) in the elderly. Late onset bipolar disorder in the elderly has a impact on the nature and course of bipolar disorder. Aims: The authors report a case of bipolar disorder emerging in late life  (76years old) with no cleary identified organic cause. Conclusion: This case highlights the importance of a broad different...

  10. Heavy resistance training and lymphedema

    DEFF Research Database (Denmark)

    Bloomquist, Kira; Karlsmark, Tonny; Christensen, Karl Bang

    2014-01-01

    BACKGROUND: There is limited knowledge regarding progressive resistance training during adjuvant chemotherapy and the risk of developing breast cancer-related lymphedema (BCRL). Furthermore, no studies have investigated the safety of resistance training with heavy loads (> 80% 1 repetition maximum......) in this population. 'Body and Cancer' is a six-week, nine-hour weekly, supervised, multimodal exercise intervention utilizing progressive resistance training with heavy loads for cancer patients undergoing chemotherapy. The purpose of the present study was to estimate the prevalence of BCRL in former participants......, and identify associations between progressive resistance training with heavy loads, and the development of BCRL. MATERIAL AND METHODS: This was a descriptive study. POPULATION: Women treated for breast cancer (n = 149), who had participated in the 'Body and Cancer' exercise intervention between 1 January 2010...

  11. Swift Heavy Ions in Matter

    Science.gov (United States)

    Rothard, Hermann; Severin, Daniel; Trautmann, Christina

    2015-12-01

    The present volume contains the proceedings of the Ninth International Symposium on Swift Heavy Ions in Matter (SHIM). This conference was held in Darmstadt, from 18 to 21 May 2015. SHIM is a triennial series, which started about 25 years ago by a joint initiative of CIRIL - Caen and GSI - Darmstadt, with the aim of promoting fundamental and applied interdisciplinary research in the field of high-energy, heavy-ion interaction processes with matter. SHIM was successively organized in Caen (1989), Bensheim (1992), Caen (1995), Berlin (1998), Catania (2002), Aschaffenburg (2005), Lyon (2008), and Kyoto (2012). The conference attracts scientists from many different fields using high-energy heavy ions delivered by large accelerator facilities and characterized by strong and short electronic excitations.

  12. Accelerators for heavy ion fusion

    International Nuclear Information System (INIS)

    Bangerter, R.O.

    1985-10-01

    Large fusion devices will almost certainly produce net energy. However, a successful commercial fusion energy system must also satisfy important engineering and economic constraints. Inertial confinement fusion power plants driven by multi-stage, heavy-ion accelerators appear capable of meeting these constraints. The reasons behind this promising outlook for heavy-ion fusion are given in this report. This report is based on the transcript of a talk presented at the Symposium on Lasers and Particle Beams for Fusion and Strategic Defense at the University of Rochester on April 17-19, 1985

  13. Weak decays of heavy quarks

    International Nuclear Information System (INIS)

    Gaillard, M.K.

    1978-08-01

    The properties that may help to identify the two additional quark flavors that are expected to be discovered. These properties are lifetime, branching ratios, selection rules, and lepton decay spectra. It is also noted that CP violation may manifest itself more strongly in heavy particle decays than elsewhere providing a new probe of its origin. The theoretical progress in the understanding of nonleptonic transitions among lighter quarks, nonleptonic K and hyperon decay amplitudes, omega minus and charmed particle decay predictions, and lastly the Kobayashi--Maskawa model for the weak coupling of heavy quarks together with the details of its implications for topology and bottomology are treated. 48 references

  14. Relativistic heavy ion facilities: worldwide

    International Nuclear Information System (INIS)

    Schroeder, L.S.

    1986-05-01

    A review of relativistic heavy ion facilities which exist, are in a construction phase, or are on the drawing boards as proposals is presented. These facilities span the energy range from fixed target machines in the 1 to 2 GeV/nucleon regime, up to heavy ion colliders of 100 GeV/nucleon on 100 GeV/nucleon. In addition to specifying the general features of such machines, an outline of the central physics themes to be carried out at these facilities is given, along with a sampling of the detectors which will be used to extract the physics. 22 refs., 17 figs., 3 tabs

  15. Heavy consumption and drink driving

    DEFF Research Database (Denmark)

    Fynbo, Lars

    2010-01-01

    This paper is part of an ongoing mixed methods project about untreated heavy alcohol consumption amongst adult Danes. It is based upon 21 in-depth qualitative interviews with convicted drink drivers. All interviewees were contacted while attending mandatory courses in “Alcohol and Traffic safety...... on the interviewee’s risk behaviour, especially in relation to driving. The interviewees are first divided into 1) a group of young “edgeworkers” with pronounced general risk behaviour, 2) a group of middle-aged “post-edgeworkers”, most with criminal records, and 3) a group of middle-aged and older heavy consumers...

  16. Heavy flavor production in QCD

    International Nuclear Information System (INIS)

    Hoyer, P.

    1989-01-01

    In this paper a brief survey is given of the status of heavy quark hadroproduction in QCD. The next-to-leading order calculation allows an estimate of the theoretical uncertainties to be made. They are manageable for top, but considerable for charm. The data on charm continues to show an excess of events at large x F , compared to QCD expectations. This may be linked to the measured anomalous A-dependence of the cross section on nuclear targets, also present at large x F . QCD models for the diffractive production of heavy quarks remain to be tested experimentally

  17. Central collisions of heavy ions

    International Nuclear Information System (INIS)

    Fung, Sun-yiu.

    1991-10-01

    This report describes the activities of the Heavy Ion Physics Group at the University of California, Riverside from October 1, 1990 to September 30, 1991. During this period, our program focuses on particle production at AGS energies, and correlation studies at the Bevalac in nucleus central collisions. We participated in the preparation of letters of intent for two RHIC experiments -- the OASIS proposal and the Di-Muon proposal -- and worked on two RHIC R ampersand D efforts -- a silicon strip detector project and a muon-identifier project. A small fraction of time was also devoted to physics programs outside the realm of heavy ion reactions by several individuals

  18. Heavy flavour production at RHIC and LHC

    Directory of Open Access Journals (Sweden)

    Innocenti Gian Michele

    2018-01-01

    Full Text Available In this proceedings, I present selected experimental results on heavy-flavour production at RHIC and at the LHC, which were presented at the Strangeness in Quark Matter 2017 conference. I will present a brief introduction to the heavy-flavour physics in heavy ion collisions and I will focus on recents measurements of in-medium energy loss and and collective properties of heavy-flavour particles, which provided important information on the mechanisms of heavy flavour interaction with the hot and dense medium created in ultra-relativistic heavy-ion collisions.

  19. Late complications of radiation therapy

    International Nuclear Information System (INIS)

    Masaki, Norie

    1998-01-01

    There are cases in which, although all traces of acute radiation complications seem to have disappeared, late complications may appear months or years to become apparent. Trauma, infection or chemotherapy may sometimes recall radiation damage and irreversible change. There were two cases of breast cancer that received an estimated skin dose in the 6000 cGy range followed by extirpation of the residual tumor. The one (12 y.o.) developed atrophy of the breast and severe teleangiectasis 18 years later radiotherapy. The other one (42 y.o.) developed severe skin necrosis twenty years later radiotherapy after administration of chemotherapy and received skin graft. A case (52 y.o.) of adenoidcystic carcinoma of the trachea received radiation therapy. The field included the thoracic spinal cord which received 6800 cGy. Two years and 8 months after radiation therapy she developed complete paraplegia and died 5 years later. A truly successful therapeutic outcome requires that the patient be alive, cured and free of significant treatment-related morbidity. As such, it is important to assess quality of life in long-term survivors of cancer treatment. (author)

  20. Late Disciform Endotheliitis after LASIK

    Directory of Open Access Journals (Sweden)

    Faik Oruçoğlu

    2013-08-01

    Full Text Available Clinical and imaging features of the patient with late herpetic keratouveitis after LASIK were investigated. A 25-year-old male patient applied with a chief complaint of blurred vision and photophobia in the left eye. He had a history of herpetic keratitits and elsewhere underwent LASIK procedure in 2005. Oral and topical acyclovir treatments were started a week ago when his complaints started. His corrected distance visual acuity was 0.2 and intraocular pressure was 14 mmHg on the left eye. Slit-lamp revealed deep central disciform edema, keratic precipitates, and 2 positive cells in the anterior chamber. Although the patient had myopic LASIK ablation, the central corneal thickness was 652 microns. Scheimpflug imaging was drawing attention to the thickening of the posterior cornea and the keratic precipitates. Sagital and anterior elevation maps were not affected, however, posterior elevation map showed marked central flattening. Asphericity value Q was within normal limits anteriorly (Q=-0.14 and it was in oblate appearance posteriorly (Q=+5.24. In addition to the antiviral medications, a topical dexamethasone treatment was started. The vision improved to 0.6, and the edema was markedly reduced after 4 days of treatment. Scheimpflug imaging parameters were significantly improved. (Turk J Ophthalmol 2013; 43: 282-5

  1. Late complications of radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Masaki, Norie [Osaka Prefectural Center for Adult Diseases (Japan)

    1998-03-01

    There are cases in which, although all traces of acute radiation complications seem to have disappeared, late complications may appear months or years to become apparent. Trauma, infection or chemotherapy may sometimes recall radiation damage and irreversible change. There were two cases of breast cancer that received an estimated skin dose in the 6000 cGy range followed by extirpation of the residual tumor. The one (12 y.o.) developed atrophy of the breast and severe teleangiectasis 18 years later radiotherapy. The other one (42 y.o.) developed severe skin necrosis twenty years later radiotherapy after administration of chemotherapy and received skin graft. A case (52 y.o.) of adenoidcystic carcinoma of the trachea received radiation therapy. The field included the thoracic spinal cord which received 6800 cGy. Two years and 8 months after radiation therapy she developed complete paraplegia and died 5 years later. A truly successful therapeutic outcome requires that the patient be alive, cured and free of significant treatment-related morbidity. As such, it is important to assess quality of life in long-term survivors of cancer treatment. (author)

  2. Severe Anaemia during Late Pregnancy

    Directory of Open Access Journals (Sweden)

    Mahenaz Akhtar

    2012-01-01

    Full Text Available Vitamin B12 deficiency is uncommon in pregnancy, it occurs in 10–28% of uncomplicated pregnancies, and is associated with a few complications. We present a case report of a 21-year-old patient with severe anaemia during late pregnancy caused by vitamin B12 deficiency. At 38 weeks gestation and with a BMI of 48.9, a history of rupture of membranes was given but not confirmed. On examination, she appeared pale and therefore full blood counts were done. Interestingly her haemoglobin (Hb levels were 3.7 g/dL. Folate and vitamin B12 levels were also found to be low, and the diagnosis of anaemia caused by vitamin B12 deficiency was made. After treatment with vitamin B12 injections, folic acid and blood transfusions, the patient’s haemoglobin levels improved from 3.7 g/dL to 10.7 g/dL. The conclusion is that effective history taking, diagnosis, and management can prevent many complications that are usually associated with vitamin B12 deficiency anaemia.

  3. General analysis of weak decay form factors in heavy to heavy and heavy to light baryon transitions

    International Nuclear Information System (INIS)

    Hussain, F.; Liu Dongsheng; Kraemer, M.; Koerner, J.G.; Tawfiq, S.

    1992-01-01

    We present a complete analysis of the heavy to heavy and heavy to light baryon semi-leptonic decays in the heavy quark effective theory within the framework of a Bethe-Salpeter (BS) approach and demonstrate the equivalence of this approach to other work in the field. We present in a compact form the baryon BS amplitudes which incorporate the symmetries manifest in the heavy quark limit and which also show clearly the light quark dynamics. A similar form of the BS amplitude is presented for light baryons. Using the BS amplitudes, the heavy to heavy and heavy to light semi-leptonic baryon decays are considered. As expected there is a dramatic reduction in the number of form factors. An advantage of our BS approach is demonstrated where the form factors are written as loop integrals which in principle can be calculated. (orig.)

  4. Childhood abuse in late-life depression

    NARCIS (Netherlands)

    Comijs, Hannie C; van Exel, Eric; van der Mast, Roos C; Paauw, Anna; Oude Voshaar, Richard; Stek, Max L

    Background: Little is known about the role of childhood abuse in late-life depression. The aim of the study is therefore to study whether childhood abuse is associated with late-life depression according to its onset, and which clinical characteristics play a role in this association. Methods: Data

  5. Are we ready to predict late effects?

    DEFF Research Database (Denmark)

    Salz, Talya; Baxi, Shrujal S; Raghunathan, Nirupa

    2015-01-01

    BACKGROUND: After completing treatment for cancer, survivors may experience late effects: consequences of treatment that persist or arise after a latent period. PURPOSE: To identify and describe all models that predict the risk of late effects and could be used in clinical practice. DATA SOURCES:...

  6. The influence of religious affiliation on heavy drinking, heavy smoking and heavy betel nut chewing.

    Science.gov (United States)

    Chen, Chiang-Ming

    2014-01-01

    The results of a national survey of determinants of drinking, smoking and betel-nut chewing behaviors are analyzed. The purpose of this paper is to empirically investigate whether drinking, smoking and betel-nut chewing are influenced by a variety of religions based on Taiwan data. Our results suggest that Buddhism, Taoism and practitioners of Chinese folk region are positively associated with heavy betel nut chewing while the religion effects on heavy smoking and drinking are statistically insignificant. Our findings on religion effects in Taiwan can be a valuable reference for comparison in Christian and western countries. © 2013 Elsevier Ltd. All rights reserved.

  7. Shock Mounting for Heavy Machines

    Science.gov (United States)

    Thompson, A. R.

    1984-01-01

    Elastomeric bearings eliminate extraneous forces. Rocket thrust transmitted from motor to load cells via support that absorbs extraneous forces so they do not affect accuracy of thrust measurements. Adapter spoked cone fits over forward end of rocket motor. Shock mounting developed for rocket engines under test used as support for heavy machines, bridges, or towers.

  8. Heavy quark physics from LEP

    International Nuclear Information System (INIS)

    Dornan, P.J.

    1997-01-01

    A review of some of the latest results on heavy flavor physics from the LEP Collaborations is presented. The emphasis is on B physics, particularly new results and those where discrepancies is given of the many techniques which have been developed to permit these analyses

  9. Heavy quark physics from LEP

    Energy Technology Data Exchange (ETDEWEB)

    Dornan, P.J. [Imperial College of Science Technology and Medicine, London (United Kingdom)

    1997-01-01

    A review of some of the latest results on heavy flavor physics from the LEP Collaborations is presented. The emphasis is on B physics, particularly new results and those where discrepancies is given of the many techniques which have been developed to permit these analyses.

  10. Future relativistic heavy ion experiments

    International Nuclear Information System (INIS)

    Pugh, H.G.

    1980-12-01

    Equations of state for nuclear matter and ongoing experimental studies are discussed. Relativistic heavy ion physics is the only opportunity to study in the laboratory the properties of extended multiquark systems under conditions such that quarks might run together into new arrangements previously unobserved. Several lines of further study are mentioned

  11. Summary of heavy ion theory

    International Nuclear Information System (INIS)

    Gavin, S.

    1994-09-01

    Can we study hot QCD using nuclear collisions? Can we learn about metallic hydrogen from the impact of comet Shoemaker-Levy 9 on Jupiter? The answer to both questions may surprise you exclamation point I summarize progress in relativistic heavy ion theory reported at DPF '94 in the parallel sessions

  12. Heavy neutral leptons at FASER

    Science.gov (United States)

    Kling, Felix; Trojanowski, Sebastian

    2018-05-01

    We study the prospects for discovering heavy neutral leptons at Forward Search Experiment (FASER), the newly proposed detector at the LHC. Previous studies showed that a relatively small detector with ˜10 m length and ≲1 m2 cross sectional area can probe large unconstrained parts of parameter space for dark photons and dark Higgs bosons. In this work, we show that FASER will also be sensitive to heavy neutral leptons that have mixing angles with the active neutrinos that are up to an order of magnitude lower than current bounds. In particular, this is true for heavy neutral leptons produced dominantly in B -meson decays, in which case FASER's discovery potential is comparable to the proposed SHiP detector. We also illustrate how the search for heavy neutral leptons at FASER will be complementary to ongoing searches in high-pT experiments at the LHC and can shed light on the nature of dark matter and the process of baryogenesis in the early Universe.

  13. Late effects of childhood leukemia therapy.

    Science.gov (United States)

    Fulbright, Joy M; Raman, Sripriya; McClellan, Wendy S; August, Keith J

    2011-09-01

    As survival rates for children treated for childhood cancers become significantly better, the focus is increasingly on determining the late effects of treatments and the best ways to monitor for them and prevent their occurrence. This review focuses on recent literature discussing the late effects of treatment in patients treated for acute myeloid leukemia and acute lymphoblastic leukemia during childhood. The late effects of therapy for childhood leukemia include secondary malignancy, cardiotoxicity, obesity, endocrine abnormalities, reproductive changes, neurocognitive deficits, and psychosocial effects. As clinicians have become more aware of the late effects of therapy, treatment regimens have been changed to decrease late effects, but patients still require long-term follow-up for their prevention and treatment.

  14. Late effects on normal tissues: oesophagus

    International Nuclear Information System (INIS)

    Pavy, J.J.; Bosset, J.F.

    1997-01-01

    Radiation-induced late effects of oesophagus are observed after treatment of various cancers. Acute reactions, mainly oesophagitis, are well known and accurately described; late effects share, for most of these, a common consequence: alteration of the main oesophageal function, namely to conduct the food bolus; clinically they are impaired in terms of mobility and stenosis. More rarely, ulcerations and pseudodiverticulae can be observed. Chemotherapy further increases the risk of late effects, especially in case of concomitant chemo-radiotherapy. All numbers and statistical data on oesophagus late effects should be regarded with caution due to recent changes in the therapeutic attitudes (more and more combined chemotherapy-radiotherapy) and some progress in given cancer locations. A common scale like the LENT-SOMA should enable the clinician to better know these late effects on oesophagus which is required to initiate effective prevention measures and adapted treatments. (authors)

  15. Origin and mixing timescale of Earth's late veneer

    Science.gov (United States)

    Prescher, C.; Allu Peddinti, D.; Bell, E. A.; Bello, L.; Cernok, A.; Ghosh, N.; Tucker, J.; Wielicki, M. M.; Zahnle, K. J.

    2012-12-01

    Experimental studies on the partitioning behavior of highly siderophile elements (HSE) between silicate and metallic melts imply that the Earth's mantle should have been highly depleted in these elements by core formation in an early magma ocean. However, present HSE contents of the Earth's mantle are ~3 orders of magnitude higher than that expected by experiments. The apparent over-abundance of HSE has commonly been explained by the addition of meteoritic material in the "late veneer" which describes the exogenous mass addition following the moon forming impact and concluding with the late heavy bombardment at ~3.8-3.9 Ga. The strongest evidence for this theory is that the platinum group element (PGE) contents in today's mantle are present in chondritic relative abundances, as opposed to a fractionated pattern expected with metal-silicate partitioning. Archean komatiites indicate that the PGE content of the Earth's mantle increased from about half their present abundances at 3.5 Ga to their present abundances at 2.9 Ga. This secular increase in PGE content suggests a progressive mixing of the late veneer material into the Earth's mantle. However, this time scale also implies that the whole mantle was relatively well mixed by 2.9 Ga. We use a compilation of existing isotopic and trace element data in order to constrain the origin and composition of the late veneer. We use PGE abundances, W abundances and W isotopic compositions in chondritic meteorites and the primitive upper mantle to compute the amount of mass delivered during the late veneer and find the late veneer mass to be ~0.6 % the mass of the bulk silicate Earth (consistent with earlier estimates). We also use the 187Re-187Os and 190Pt-186Os systems to constrain the composition and timing of delivery of the impacting population. We model the efficiency of mantle mixing in this time frame by using 3-dimensional numerical geodynamical simulations and geochemical constraints. Initial parameters include the

  16. Late Abortion: A Comprehensive Review

    Directory of Open Access Journals (Sweden)

    Sheng Chiang

    2005-12-01

    Full Text Available Late termination of pregnancy (LTOP is defined as an abortion carried out beyond 24 gestational weeks, when the fetus has arguably attained viability. In Taiwan, the current abortion law, bearing a eugenic title, allows LTOP on certain medical grounds. However, the fetal and maternal conditions that constitute medical grounds are not clarified and remain legally untested. Professional debate on the abortion issue is also lacking in academia in Taiwan, despite societal concerns. With the advent of technology to detect fetal abnormalities, obstetricians are now confronted more frequently with acute dilemmas regarding LTOP. Quite often, they sail in an uncharted sea with no clinical guidelines from their professional societies or affiliated hospitals. Recently, LTOP at 35 gestational weeks for a fetus with Down syndrome, complicated with polyhydramnios and tetralogy of Fallot, triggered media scrutiny and aroused much public attention. Although the clinical decision making for pregnancies with fetal abnormalities entails increasingly balanced information and consideration in terms of the medical, ethical, legal, psychologic, and societal aspects, society at large is unaware of the complexity and intertwined nature of various abortion issues, especially LTOP. Obstetricians are now in a vulnerable position in Taiwanese society, where litigations relevant to the practice of early abortions are not rare. Therefore, a global and in-depth look into abortion issues from legal and ethical dimensions is indispensable for modern obstetric practice. This review considers the core issues in LTOP, including what conditions constitute a “serious” fetal abnormality to justify LTOP, the incidence of LTOP, legislation regarding LTOP in Western countries, and recent research on ambivalent fetal pain. It will also present procedures, some under the auspices of the ethical committee of a Presbyterian hospital in Taiwan, for clinical decision making, particularly

  17. Heavy metals in Mindhola river estuary, India

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.; Rokade, M.A; Mandalia, A

    The heavy metal concentrations are studied along the Mindhola river estuary. Surface and bottom water samples were collected using Niskin Sampler. The sediment samples were collected using a Van Veen grab. The heavy metal concentration is estimated...

  18. Heavy particle radiotherapy: prospects and pitfalls

    International Nuclear Information System (INIS)

    Faju, M.R.

    1980-01-01

    The use of heavy particles in radiotherapy of tumor volumes is examined. Particles considered are protons, helium ions, heavy ions, negative pions, and fast neutrons. Advantages and disadvantages are discussed

  19. Heavy water. A production alternative for Venezuela

    International Nuclear Information System (INIS)

    A survey of heavy water production methods is made. Main facts about isotopic and distillation methods, reforming and coupling to a Hydrogen distillation plant are presented. A feasibility study on heavy water production in Venezuela is suggested

  20. Late consequences of ARS survivors of different γβ- and γη-radiation injuries

    International Nuclear Information System (INIS)

    Nadejina, N.M.; Galstian, I.A.; Savitsky, A.A.; Rtischeva, J.N.; Uvacheva, I.V.; Kashirina, O.G.

    2000-01-01

    Purpose: to study of health in the late consequences period the acute radiation syndrome (ARS) survivors of different radiation accidents took place in former USSR since 1953. Method: clinical observation, clinical database. Results: radiation cataract were revealed at the survivors who have undergone relatively uniform γβ-radiation exposure in a doze not less 2.0 Gy. At non-uniform γη-radiation exposure the cataract development was observed at smaller dozes for bone marrow. The local radiation injures of skin were observed at relatively uniform γβ- and at non-uniform γη-radiation exposure. The main factors for working disability are the presence of relapsing late radiation ulcers in the late period of local γβ-injures 2-4 degrees and the presence of amputation stumps at γη-radiation exposure. For oncologic diseases developed in the period of late consequences of ARS the dose dependence is not revealed. Transient different changes of blood parameters are not dose dependent. The repeated (relatively stable) changes, as a rule, are connected to presence of heavy accompanying diseases (chronic hepatitis, myelodysplastic syndrome, family neutropenia). We observed development of chronic myeloleukemia at the ARS survivor. Hospital morbidity of these groups of ARS survivors demonstrates absence of the radiation influence to development of somatic pathology in the period of the late consequences. Conclusion: health of the ARS survivors in the late consequences period is determined by presence of consequences of local radiation injures of skin, radiation cataract and different concurrent somatic diseases. The type of irradiation (γβ- and γη-) in many respects determines the speed of occurrence, expression and some clinical features of the late consequences of local radiation injures. (author)

  1. Study of the heavy water regeneration processes

    International Nuclear Information System (INIS)

    Cavcic, E.

    1965-11-01

    Experience derived from heavy water reactor operation showed degradation and dilution of heavy water to be inevitable and depends on the type of reactor. Dilution of heavy water during operation of the RA and the RB reactors is shown in this report. Principles and procedures of heavy water regeneration by electrolysis, fractional distillation, cleaning, prevention of tritium contamination are described as well as separation columns

  2. Nuclear physics with heavy ions. 1

    International Nuclear Information System (INIS)

    Reif, R.; Schmidt, R.

    1981-01-01

    Some results obtained in nuclear physics with heavy ions in the energy range up to 10 MeV/nucleon are summarized. A short review of the tendencies in the development of heavy ion accelerators is followed by a classification of the mechanisms observed in heavy ion interactions. The characteristics of the various types of reactions are presented. Applications of heavy ion beams in other branches of sciences are discussed. (author)

  3. Trend of heavy metal and sulphur deposition in Finland from the 1980`s to 1990`s

    Energy Technology Data Exchange (ETDEWEB)

    Kubin, E.; Lippo, H. [Forest Research Inst., Muhos (Finland)

    1995-12-31

    The moss technique to survey atmospheric heavy metal deposition was developed in Sweden in the late 1960`s. The surveys has extended from regional and national basis to cover all the Nordic countries in 1985, to northern Europe in 1990 and to a large part of Europe in 1990-92. National reports have also been published in many countries. The Forest Research Institute established a network of 3009 secret permanent monitoring sites all over the country in 1985 and 1986 for forest inventory and for monitoring the situation and changes in the forests. One essential part has been to study the effects of air pollution - including heavy metal and sulphur deposition on forests. Deposition has been monitored by collecting bioindicators and analysing the element concentrations. The purpose of this report is to show the trend of the heavy metal and sulphur deposition from the 1980`s to 1990`s and in addition to produce information about the emission sources. (author)

  4. Trend of heavy metal and sulphur deposition in Finland from the 1980`s to 1990`s

    Energy Technology Data Exchange (ETDEWEB)

    Kubin, E; Lippo, H [Forest Research Inst., Muhos (Finland)

    1996-12-31

    The moss technique to survey atmospheric heavy metal deposition was developed in Sweden in the late 1960`s. The surveys has extended from regional and national basis to cover all the Nordic countries in 1985, to northern Europe in 1990 and to a large part of Europe in 1990-92. National reports have also been published in many countries. The Forest Research Institute established a network of 3009 secret permanent monitoring sites all over the country in 1985 and 1986 for forest inventory and for monitoring the situation and changes in the forests. One essential part has been to study the effects of air pollution - including heavy metal and sulphur deposition on forests. Deposition has been monitored by collecting bioindicators and analysing the element concentrations. The purpose of this report is to show the trend of the heavy metal and sulphur deposition from the 1980`s to 1990`s and in addition to produce information about the emission sources. (author)

  5. New theoretical results in heavy quark hadroproduction

    International Nuclear Information System (INIS)

    Nason, P.

    1992-01-01

    We describe the status of the heavy quark hadroproduction theory. In particular, we discuss recent developments on production of heavy quarks in the high energy limit, and the results of a new calculation to next-to-leading accuracy of the fully exclusive parton cross section for heavy quark production. (orig.)

  6. BROOKHAVEN: Looking towards heavy ion physics

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    July 11-22 were busy days at Brookhaven with a two-week Summer Institute on Relativistic Heavy Ion Physics. After an intensive first week designed to introduce young physicists to high energy heavy ion research, the second week was a workshop on detector technology for Brookhaven's proposed Relativistic Heavy Ion Collider (RHIC), attended by some 150 physicists

  7. Therapy tumor with the heavy ions beam

    International Nuclear Information System (INIS)

    Dang Bingrong; Wei Zengquan; Li Wenjian

    2002-01-01

    As physical characteristic of heavy ions Bragg peak, therapy tumor with heavy ions is becoming advanced technology. So, many countries have developed the technology and used to treat tumor, the societal and economic effects are beneficial to people. The authors show the development, present situation and information of research in world of advanced radiotherapy with heavy ions

  8. Spectroscopy of heavy few-electron ions

    International Nuclear Information System (INIS)

    Mokler, P.H.

    1986-07-01

    In this paper we ask first, why is it interesting to investigate heavy-few electron ions. Then the various accelerator-based methods to produce heavy few-electron ions are discussed. In the main part an overview on available heavy few-electron ion data and current experiments is given. The summary will end up with future aspects in this field. (orig.)

  9. Polarization phenomena in heavy-ion reactions

    International Nuclear Information System (INIS)

    Sugimoto, K.; Ishihara, M.; Takahashi, N.

    1984-01-01

    This chapter presents a few key experiments which provide direct evidence of the polarization phenomena in heavy-ion reactions. The theory of polarization observables and measurements is given with the necessary formulae. The polarization phenomena is described and studies of product nuclear polarization in heavy-ion reactions are discussed. Studies of heavy-ion reactions induced by polarized beams are examined

  10. Formation of heavy quarks in ultrarelativistic heavy-ion collisions

    International Nuclear Information System (INIS)

    Schneider, S.M.; Greiner, W.; Soff, G.

    1992-02-01

    We investigate the production of heavy quarks in continuum and bound states in nuclear collisions. Creation for free banti b and tanti t quark pairs and for bottomonium and toponium in the ground state are computed at RHIC, LHC and SSC energies. Central and peripheral heavy-ion collisions are discussed. For top quark creation we assumed a mass range of 90 GeV ≤ m t ≤ 250 GeV. The creation rate for top quarks on peripheral collisions is estimated to be by a factor 40 to 130 smaller compared with corresponding central collisions. For m t = 130 GeV we calculated a creation rate of about 4760 top quark pairs per day at the LHC (3.5 TeV/u) for Pb-Pb collisions. (orig.)

  11. 77 FR 4678 - Nonconformance Penalties for On-Highway Heavy Heavy-Duty Diesel Engines

    Science.gov (United States)

    2012-01-31

    ...), optimized turbo-charging, optimized fuel injection, diesel particulate filters), plus liquid urea based...-Highway Heavy Heavy-Duty Diesel Engines AGENCY: Environmental Protection Agency (EPA). ACTION: Interim... manufacturers of heavy heavy-duty diesel engines in model years 2012 and 2013 for emissions of oxides of...

  12. Heavy ions: Report from Relativistic Heavy Ion Collider

    Indian Academy of Sciences (India)

    2012-10-12

    Oct 12, 2012 ... Experiments using ultrarelativistic heavy-ion collisions study nuclear matter under ... sN N = 10 GeV for Pb+Pb collisions, corresponding to an initial .... quenching through systematic comparisons of data to models, and .... the RdAu and RCP = (0−20%)/(60−80%) factors for the J/ψ production in d+Au col-.

  13. Heavy flavour production at CMS in heavy ion collisions

    CERN Document Server

    Nguyen, Matthew

    2015-01-01

    We review recent results relating to beauty production in heavy-ion collisions, in both the closed and open heavy flavor sectors, from the CMS experiment at the LHC. The sequential suppression of the ° states in PbPb collisions is thought to be evidence of the dissociation of quarkonia bound states in deconfined matter. Data from pPb collisions demonstrate that while cold nuclear effects appear to be subdominant in minimum bias collisions, there exists a non-trivial dependence on collision multiplicity that remains to be understood. The suppression of high p T particles in heavy-ion collisions, relative to the expectation from pp collisions, is typically interpreted in terms of energy loss of hard scattered parton in the dense nuclear medium. The flavor dependence of the energy loss may be accessed via measurements of b hadrons and b-tagged jets. Measurement of B mesons, via non-prompt J = y , at relatively low p T indicate a smaller suppression factor than D meson or inclusive charged hadrons. Data on b jet...

  14. Late Paleogene reticulate Nummulites of the Western Tethys

    Science.gov (United States)

    Less, G.; Kertész, B.; Özcan, E.

    2012-04-01

    positions. The inner cross-diameter of the proloculus has been proven to be the most reliable evolutionary parameter. Beside, the evolution of surface characteristics (not detailed here) is also usable in this sense, although it shows great intrapopulational variation partly because of the ontogeny. The increase of the average length of chambers (accompanied by general flattening) in the third whorl is of secondary importance in recognizing the evolution of the group because it is affected also by ecological factors. Finally, the tightness/laxity of the spire and the relative width of the spiral cord in the third whorl are clearly the functions of the actual paleoenvironment. As a result, the Nummulites fabianii-fichteli group is proven to form a single but rather variable evolutionary lineage within the early Bartonian to early Chattian development of which six evolutionary stages (considered as species) could be recognized (we could not study the middle-late Lutetian precursor forms). The safety of identification of these evolutionary stages with particular species names is of different degree. The six species are defined primarily on the basis of the average inner cross-diameter of the proloculus (Pmean) and secondarily by the surface characteristics as follows: - Nummulites bullatus (late Lutetian to basal Bartonian, SBZ 16 to early SBZ 17 zone): Pmean = 65-100 µm; granules, no reticulation. - N. garganicus (early to middle late Bartonian, late SBZ 17 to SBZ 18B): Pmean = 100-140 µm; heavy granules + reticulation. - N. hormoensis (late Bartonian, SBZ 18): Pmean = 140-200 µm; heavy granules + umbo + reticulation. - N. fabianii (Priabonian to early Rupelian, SBZ 19-21): Pmean = 200-320 µm; heavy reticulation + umbo + weak granules. - N. fichteli (late Priabonian to early Rupelian, SBZ 20-21): Pmean = 200-300 µm, weak reticulation to irregular mesh. - N. bormidiensis (late Rupelian, SBZ 22A): Pmean = 300-450 µm; irregular mesh. This research was supported by the

  15. LATE VISION: PROCESSES AND EPISTEMIC STATUS

    Directory of Open Access Journals (Sweden)

    Athanassios eRaftopoulos

    2011-12-01

    Full Text Available In this paper, I examine the processes that occur in late vision and address the problem of whether late vision should be construed as a properly speaking perceptual stage, or as a thought-like discursive stage. Specifically, I argue that late vision, its (partly conceptual nature notwithstanding, neither is constituted by nor does it implicate what I call pure thoughts, that is, propositional structures that are formed in the cognitive areas of the brain through, and participate in, discursive reasoning and inferences. At the same time, the output of late vision, namely an explicit belief concerning the identity and category membership of an object (that is, a recognitional belief or its features, eventually enters into discursive reasoning. Using Jackendoff’s distinction between visual awareness, which characterizes perception, and visual understanding, which characterizes pure thought, I claim that the contents of late vision belong to visual awareness and not to visual understanding and that although late vision implicates beliefs, either implicit or explicit, these beliefs are hybrid visual/conceptual constructs and not pure thoughts. Distinguishing between these hybrid representations and pure thoughts and delineating the nature of the representations of late vision lays the ground for examining, among other things, the process of conceptualization that occurs in visual processing and the way concepts modulate perceptual content affecting either its representational or phenomenal character. I also do not discuss the epistemological relations between the representations of late vision and the perceptual judgments they ‘support’, or ‘guide’ or ‘render possible’ or ‘evidence’ or ‘entitle’. However, the specification of the epistemology of late vision lays the ground for attacking that problem as well.

  16. Late Onset Bipolar Disorder: Case Report

    Directory of Open Access Journals (Sweden)

    Filipa Araújo

    2016-07-01

    Full Text Available Background: Bipolar disorder affects approximately 1% of the population, with diagnosis often being made during late adolescence and early adulthood, and only rarely (0.1% in the elderly. Late onset bipolar disorder in the elderly has a impact on the nature and course of bipolar disorder. Aims: The authors report a case of bipolar disorder emerging in late life  (76years old with no cleary identified organic cause. Conclusion: This case highlights the importance of a broad differential diagnosis and pharmacologic management when approaching new-onset manic/depressive symptoms among geriatric patients.

  17. Late washing filter cleaning cycle demonstration

    International Nuclear Information System (INIS)

    Meyer, M.L.; McCabe, D.J.

    1992-01-01

    The DWPF Late Washing Facility will filter cesium and potassium tetraphenyl borate (TPB) solids using a Mott sintered metal filter, identical to the filter now used in the In-tank Precipitation Facility. The purpose of the late wash step is primarily to remove the nitrite salts from the slurry prior to delivery to DWPF. Periodic chemical cleaning of the filter will be required, presumably after each batch although the actual required frequency could not be determined on the lab-scale. Minimization of chemical cleaning solution volumes is key to maximizing the attainment of the Late Wash facility. This report summarizes work completed in experiments designed to identify minimum cleaning solution requirements

  18. Scaling behaviour of leptonic decay constants for heavy quarkonia and heavy mesons

    International Nuclear Information System (INIS)

    Kiselev, V.V.

    1994-01-01

    In the framework of QCD sum rules one uses a scheme, allowing one to apply the conditions of both nonrelativistic heavy quark motion inside mesons and the heavy quark flavour independence of nonsplitting nS-state density. In the leading order an analitic expression is derived for leptonic constants of both heavy quarkonia and heavy mesons with a single heavy quark. The expression allows one explicitly to determine scaling properties of the constants. 24 refs., 2 tabs

  19. Argonne superconducting heavy-ion linac

    Energy Technology Data Exchange (ETDEWEB)

    Bollinger, L.M.; Benaroya, R.; Clifft, B.E.; Jaffey, A.H.; Johnson, K.W.; Khoe, T.K.; Scheibelhut, C.H.; Shepard, K.W.; Wangler, Y.Z.

    1976-01-01

    A summary is given of the status of a project to develop and build a small superconducting linac to boost the energy of heavy ions from an existing tandem electrostatic accelerator. The design of the system is well advanced, and construction of major components is expected to start in late 1976. The linac will consist of independently-phased resonators of the split-ring type made of niobium and operating at a temperature of 4.2/sup 0/K. The resonance frequency is 97 MHz. Tests on full-scale resonators lead one to expect accelerating fields of approximately 4 MV/m within the resonators. The linac will be long enough to provide a voltage gain of at least 13.5 MV, which will allow ions with A less than or approximately 80 to be accelerated above the Coulomb barrier of any target. The modular nature of the system will make future additions to the length relatively easy. A major design objective is to preserve the good quality of the tandem beam. This requires an exceedingly narrow beam pulse, which is achieved by bunching both before and after the tandem. Focusing by means of superconducting solenoids within the linac limit the radial size of the beam. An accelerating structure some 15 meters downstream from the linac will manipulate the longitudinal phase ellipse so as to provide the experimenter with either very good energy resolution (..delta..E/E approximately equal to 2 x 10/sup -4/) or very good time resolution (..delta.. t approximately equal to 30 psec).

  20. Heavy flavor production from photons and hadrons

    International Nuclear Information System (INIS)

    Heusch, C.A.

    1982-01-01

    The present state of the production and observation of hadrons containing heavy quarks or antiquarks as valence constituents, in reactions initiated by real and (space-like) virtual photon or by hadron beams is discussed. Heavy flavor production in e + e - annihilation, which is well covered in a number of recent review papers is not discussed, and similarly, neutrino production is omitted due to the different (flavor-changing) mechanisms that are involved in those reactions. Heavy flavors from spacelike photons, heavy flavors from real photons, and heavy flavors from hadron-hadron collisions are discussed

  1. Calorimetric cryodetectors for heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Egelhof, P; Henning, W; Kienlin, A v; Meier, J; Truebenbacher, V [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany, F.R.) Mainz Univ. (Germany, F.R.). Inst. fuer Physik; Azgui, F [CDTN, Algiers (Algeria); Shepard, K [Argonne National Lab., IL (USA)

    1990-01-01

    Status and first test results are reported for a project to develop calorimetric cryodetectors for heavy ions. The special conditions for the detection of energetic heavy ions are discussed. Presently the investigations are focussed on semiconductor bolometers and aluminium-strip superconducting phase-transition thermometers that are cooled with liquid {sup 4}He and operate in the temperature range 1.3-4.2 K. For a germanium bolometer the temperature dependence of the resistance, voltage-current curves, the time response to heating by voltage pulses and the response to ionizing {alpha}-radiation are reported. First tests on phase transition thermometers using thin aluminum strips yield a transition width of {Delta}T=8.6 mK at T{sub c}=1.467 K. (orig.).

  2. Physics of Ultrarelativistic Heavy Ions

    International Nuclear Information System (INIS)

    Giubellino, P.

    1996-01-01

    This paper is devoted to a general presentation of the physics of Ultrarelativistic Heavy Ions, as seen from the experimentalist close-quote s point of view. The aim of this research is the study of nuclear matter under extreme conditions of temperature and pressure, extending in this way our understanding of the strong interactions in general, and of colour confinement in particular. This young field of Physics has been growing rapidly in the past years, and any attempt to cover it in few pages will be rather sketchy and many important aspects will have to be left out. I will mainly try to cover the general motivations to undertake this study, and just mention the experimental challenges to be faced, the results from the experiments at CERN and BNL, and finally the fascinating program ahead of us, with a glimpse at the CERN LHC used as a heavy-ion collider. copyright 1996 American Institute of Physics

  3. RHIC heavy ion operations performance

    CERN Document Server

    Satogata, T; Ferrone, R; Pilat, F

    2006-01-01

    The Relativistic Heavy Ion Collider (RHIC) completed its fifth year of operation in 2005, colliding copper ion beams with ps=200 GeV/u and 62.4 GeV/u[1]. Previous heavy ion runs have collided gold ions at ps=130 GeV/u, 200 GeV/u, and 62.4 GeV/u[2], and deuterons and gold ions at ps=200 GeV/u[3]. This paper discusses operational performance statistics of this facility, including Cu- Cu delivered luminosity, availability, calendar time spent in physics stores, and time between physics stores. We summarize the major factors affecting operations efficiency, and characterize machine activities between physics stores.

  4. Process of distilling heavy hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    1929-12-03

    This invention has for its object the distillation of heavy liquid hydrocarbons for the purpose of obtaining lighter hydrocarbons stable and immediately salable for fuels in combustion motors. The process is distinguished by the fact that the heavy hydrocarbon is distilled by means of heating to a temperature in keeping with the nature of the material to be treated up to 350/sup 0/C under pressure or without pressure the distillation being carried out on catalysts containing successively nickel, copper, and iron (3 parts of nickel, 1 part of copper, and 1 part of iron), the vapors produced by this distillation being exposed in turn to the action of catalysts of the same nature and in the same proportion.

  5. Heavy flavor measurements at LHC

    CERN Document Server

    Spagnolo, S; The ATLAS collaboration

    2013-01-01

    ATLAS and CMS measurements in the area of heavy flavor physics are reviewed with focus on the most recent results. The topics discussed include heavy flavor production rates and properties, exclusive b-hadron production, with attention to the recent observations of rare b-hadrons and to the measurements of Lambda_b production cross section, lifetime and mass. Differential production cross sections and polarization measurements of Upsilon states are presented, along with production ratios of chi_c states in the charmonium system. Evidence for a new Xsi_b state and observations of structures in the J/Psi phi spectrum from B+- decays to J/Psi phi K+- in the CMS data are also reported. Precision studies of the Bs system and determination of CP-violation sensitive parameters are discussed. Finally the status of the searches for rare decays is presented.

  6. Heavy flavor measurements at LHC

    CERN Document Server

    Spagnolo, S; The ATLAS collaboration

    2013-01-01

    ATLAS and CMS measurements in the area of heavy flavor physics are reviewed with focus on the most recent results. The topics discussed include heavy flavor production rates and properties, exclusive b-hadron production, with attention to the recent observations of rare b-hadrons and to the precise measurements of Lambda_b production cross section, lifetime and mass. Differential production cross sections and polarization measurements of Upsilon states are presented, along with production ratios of chi_c states in the charmonium system. Evidence for a new Xsi_b state and observations of structures in the J/Psi phi spectrum from B+- decays to J/Psi phi K+- in the CMS data are also reported. Precision studies of the Bs system and determination of CP-violation sensitive parameters are discussed. Finally the status of the searches for rare FCNC decays is presented.

  7. Micromycetes sensitiveness to heavy metals

    Directory of Open Access Journals (Sweden)

    O. N. Korinovskaya

    2011-07-01

    Full Text Available The sensitivity of 33 micromycete species to nitric compounds of copper, lead, zinc, nickel and cadmium has been determined. Absidia butleri Lendn, Mortierella vanesae Dixon-Stewart, Cunninghamella echinulata Thaxte, Curvularia tuberculata Jain, Cladosporium cladosporiodes (Fresen G. A. de Vries and Fusarium solani (C. Mart. Appel et Wollenw are sensitive to minimal content of the heavy metals (0.75 of maximum permissible concentration (MPC in the growth medium. At the same time Trixoderma longibrachiatiim Rifai, Alternaria alternatа (Fr. Keissl and Penicillium sp. 4 demonstrated moderate growth under maximal concentration (50 MPC. It is determined that minimal content of the heavy metals in the initial stage of influence (up to 48 h promotes growth of only Fusarium oxysporum E. F. Sm. et Swingle, while retards growth of the other species.

  8. Heavy ion accelerators at GSI

    International Nuclear Information System (INIS)

    Angert, N.

    1984-01-01

    The status of the Unilac heavy ion linear accelerator at GSI, Darmstadt is given. A schematic overall plan view of the Unilac is shown and its systems are described. List of isotopes and intensities accelerated at the Unilac is presented. The experimental possibilities at GSI should be considerably extended by a heavy ion synchrotron (SIS 18) in combination with an experimental storage ring (ESR). A prototype of the rf-accelerating system of the synchrotron has been built and tested. Prototypes for the quadrupole and dipole magnets for the ring are being constructed. The SIS 18 is desigmed for a maximum magnetic rigidity of 18Tm so that neon can be accelerated to 2 GeV/W and uranium to 1 GeV/u. The design allows also the acceleration of protons up to 4.5 GeV. The ESR permits to storage fully stripped uranium ions up to an energy of approximately R50 MeV/u

  9. Mutation induction by heavy ions

    Science.gov (United States)

    Kiefer, J.; Stoll, U.; Schneider, E.

    1994-10-01

    Mutation induction by heavy ions is compared in yeast and mammalian cells. Since mutants can only be recovered in survivors the influence of inactivation cross sections has to be taken into account. It is shown that both the size of the sensitive cellular site as well as track structure play an important role. Another parameter which influences the probability of mutation induction is repair: Contrary to naive assumptions primary radiation damage does not directly lead to mutations but requires modification to reconstitute the genetic machinery so that mutants can survive. The molecular structure of mutations was analyzed after exposure to deuterons by amplification with the aid of polymerase chain reaction. The results-although preliminary-demonstrate that even with densely ionizing particles a large fraction does not carry big deletions which suggests that point mutations may also be induced by heavy ions.

  10. Semiholography for heavy ion collisions

    CERN Document Server

    Mukhopadhyay, Ayan

    2017-01-01

    The formation of QGP in heavy ion collisions gives us a great opportunity for learning about nonperturbative dynamics of QCD. Semiholography provides a new consistent framework to combine perturbative and non-perturbative effects in a coherent way and can be applied to obtain an effective description for heavy ion collisions. In particular, it allows us to include nonperturbative effects in existing glasma effective theory and QCD kinetic theory for the weakly coupled saturated degrees of freedom liberated by the collisions in the initial stages in a consistent manner. We argue why the full framework should be able to confront experiments with only a few phenomenological parameters and present feasibility tests for the necessary numerical computations. Furthermore, we discuss that semiholography leads to a new description of collective flow in the form of a generalised non-Newtonian fluid. We discuss some open questions which we hope to answer in the near future.

  11. Heavy-ion-spectrometer system

    International Nuclear Information System (INIS)

    1982-05-01

    LBL safety policy (Pub 300 Appendix E) states that every research operation with a Class A risk potential (DOE 5484.1) should identify potentially hazardous procedures associated with the operation and develop methods for accomplishing the operation safely without personnel injury or property damage. The rules and practices that management deems to be minimally necessary for the safe operations of the Heavy Ion Spectrometer System (HISS) in the Bevatron Experimental Hall (51B) are set forth in this Operation Safety Procedures

  12. Experiments with stored heavy ions

    International Nuclear Information System (INIS)

    Fick, D.; Habs, D.; Jaeschke, E.

    1985-02-01

    The success of newly-developed methods of phase space cooling in proton and antiproton storage rings was sufficient for an examination of whether these methods could also be applied in storage rings for heavy ions. An expansion of these methods to heavy ion beams seems attractive for all sorts of reasons. Recently, this area was extensively discussed in a series of working meetings with the result that heavy ion storage rings are to be built for use in atomic and nuclear physics, with integrated radiation cooling and stochastic cooling, but primarily electron cooling. The current state of research and planning for the storage experiment is described. It is not intended to be a structural specification worked out in detail. The general design of the ring, however, has been established, and experimental details have deliberately been kept flexible, to thereby allow very different sorts of experiments to be conducted. The ring described with a maximum magnetic rigidity of Bp = 1.5 Tm, is designed in quadripartite symmetry. The total circumference is approximately 35 m, and there are four straight sections each 3.5 m long for the electron cooling sections, the experimental equipment, as well as HF system and injection. One of the most desirable properties of the reservoir is the multi-charge mode, which will significantly improve the operation which heavy ion beams, which reverse charge in electron cooling sections, target and residual vacuum. Initial considerations are presented with regard to stochastic and electron cooling. A review of possible classes of experiments is given and the schedule and financing of the project is outlined. 46 refs

  13. Computing for Heavy Ion Physics

    International Nuclear Information System (INIS)

    Martinez, G.; Schiff, D.; Hristov, P.; Menaud, J.M.; Hrivnacova, I.; Poizat, P.; Chabratova, G.; Albin-Amiot, H.; Carminati, F.; Peters, A.; Schutz, Y.; Safarik, K.; Ollitrault, J.Y.; Hrivnacova, I.; Morsch, A.; Gheata, A.; Morsch, A.; Vande Vyvre, P.; Lauret, J.; Nief, J.Y.; Pereira, H.; Kaczmarek, O.; Conesa Del Valle, Z.; Guernane, R.; Stocco, D.; Gruwe, M.; Betev, L.; Baldisseri, A.; Vilakazi, Z.; Rapp, B.; Masoni, A.; Stoicea, G.; Brun, R.

    2005-01-01

    This workshop was devoted to the computational technologies needed for the heavy quarkonia and open flavor production study at LHC (large hadron collider) experiments. These requirements are huge: peta-bytes of data will be generated each year. Analysing this will require the equivalent of a few thousands of today's fastest PC processors. The new developments in terms of dedicated software has been addressed. This document gathers the transparencies that were presented at the workshop

  14. Heavy metals in sea turtles

    Energy Technology Data Exchange (ETDEWEB)

    Witkowski, S.A. (Millersville State College, PA); Frazier, J.G.

    1982-07-01

    Bone and barnacle samples from sea turtles (Hepidochelys olivacea) in Ecuador were analyzed for manganese, iron, copper, zinc and lead. Analysis was performed by flame atomic absorption spectroscopy. Results show that zinc and iron levels in bone and barnacles were greater than copper, manganese and lead levels. The significance of the findings is difficult to interpret because so little is known about baseline levels and physiological effects of heavy metals in the animals. (JMT)

  15. Computing for Heavy Ion Physics

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, G.; Schiff, D.; Hristov, P.; Menaud, J.M.; Hrivnacova, I.; Poizat, P.; Chabratova, G.; Albin-Amiot, H.; Carminati, F.; Peters, A.; Schutz, Y.; Safarik, K.; Ollitrault, J.Y.; Hrivnacova, I.; Morsch, A.; Gheata, A.; Morsch, A.; Vande Vyvre, P.; Lauret, J.; Nief, J.Y.; Pereira, H.; Kaczmarek, O.; Conesa Del Valle, Z.; Guernane, R.; Stocco, D.; Gruwe, M.; Betev, L.; Baldisseri, A.; Vilakazi, Z.; Rapp, B.; Masoni, A.; Stoicea, G.; Brun, R

    2005-07-01

    This workshop was devoted to the computational technologies needed for the heavy quarkonia and open flavor production study at LHC (large hadron collider) experiments. These requirements are huge: peta-bytes of data will be generated each year. Analysing this will require the equivalent of a few thousands of today's fastest PC processors. The new developments in terms of dedicated software has been addressed. This document gathers the transparencies that were presented at the workshop.

  16. Micromycetes sensitiveness to heavy metals

    OpenAIRE

    O. N. Korinovskaya; V. N. Gryshko

    2011-01-01

    The sensitivity of 33 micromycete species to nitric compounds of copper, lead, zinc, nickel and cadmium has been determined. Absidia butleri Lendn, Mortierella vanesae Dixon-Stewart, Cunninghamella echinulata Thaxte, Curvularia tuberculata Jain, Cladosporium cladosporiodes (Fresen) G. A. de Vries and Fusarium solani (C. Mart.) Appel et Wollenw are sensitive to minimal content of the heavy metals (0.75 of maximum permissible concentration (MPC)) in the growth medium. At the same time Trixoderm...

  17. Heavy-ion-spectrometer system

    Energy Technology Data Exchange (ETDEWEB)

    1982-05-01

    LBL safety policy (Pub 300 Appendix E) states that every research operation with a Class A risk potential (DOE 5484.1) should identify potentially hazardous procedures associated with the operation and develop methods for accomplishing the operation safely without personnel injury or property damage. The rules and practices that management deems to be minimally necessary for the safe operations of the Heavy Ion Spectrometer System (HISS) in the Bevatron Experimental Hall (51B) are set forth in this Operation Safety Procedures (OSP).

  18. Computing for Heavy Ion Physics

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, G; Schiff, D; Hristov, P; Menaud, J M; Hrivnacova, I; Poizat, P; Chabratova, G; Albin-Amiot, H; Carminati, F; Peters, A; Schutz, Y; Safarik, K; Ollitrault, J Y; Hrivnacova, I; Morsch, A; Gheata, A; Morsch, A; Vande Vyvre, P; Lauret, J; Nief, J Y; Pereira, H; Kaczmarek, O; Conesa Del Valle, Z; Guernane, R; Stocco, D; Gruwe, M; Betev, L; Baldisseri, A; Vilakazi, Z; Rapp, B; Masoni, A; Stoicea, G; Brun, R

    2005-07-01

    This workshop was devoted to the computational technologies needed for the heavy quarkonia and open flavor production study at LHC (large hadron collider) experiments. These requirements are huge: peta-bytes of data will be generated each year. Analysing this will require the equivalent of a few thousands of today's fastest PC processors. The new developments in terms of dedicated software has been addressed. This document gathers the transparencies that were presented at the workshop.

  19. Radiation from heavy ion collisions

    International Nuclear Information System (INIS)

    Kast, J.R.; Lee, Y.K.

    1975-01-01

    A study of x rays produced in heavy ion collisions has led to a search for molecular orbital x rays, concentrating on 35 Cl ions on Al, NaCl, and C targets. Preliminary analysis of the angular dependence of continuum x rays has tentatively identified quasi-molecular K x rays. Other work completed and in progress is discussed. (3 figures) (U.S.)

  20. Heavy-ion radiation chemistry

    International Nuclear Information System (INIS)

    Imamura, Masashi

    1975-01-01

    New aspect of heavy ion radiation chemistry is reviewed. Experiment has been carried out with carbon ions and nitrogen ions accelerated by a 160 cm cyclotron of the Institute of Physical and Chemical Research. The results of experiments are discussed, taking into consideration the effects of core radius depending on heavy ion energy and of the branch tracks of secondary electrons outside the core on chemical reaction and the yield of products. The effect of core size on chemical reaction was not able to be observed, because the incident energy of heavy ions was only several tens of MeV. Regarding high radical density, attention must be given to the production of oxygen in the core. It is possible to produce O 2 in the core in case of high linear energy transfer (LET), while no production of O 2 in case of low LET radiation. This may be one of study problems in future. LET effects on the yield of decomposed products were examined on acetone, methyl-ethyl-ketone and diethyl ketone, using heavy ions (C and N) as well as gamma radiation and helium ions. These three ketones showed that the LET change of two gaseous products, H 2 and CO, was THF type. There are peaks at 50-70 eV/A in the yield of both products. The peaks suggest the occurrence of ''saturation'' in decomposition. Attention was drawn to acetone containing a small amount (2 wt.%) of H 2 O. H 2 O and CO produced from this system differ from those in the pure system. The hydrogen connection formed by such a small amount of H 2 O may mediate the energy transfer. Sodium acetate tri-hydrate produces CH 3 radical selectively by gamma-ray irradiation at 77 K. In this case, the production of CH 2 COO - increases with the increase of LET of radiation. This phenomenon may be an important study problem. (Iwakiri, K.)

  1. Direction of Heavy Water Projects

    International Nuclear Information System (INIS)

    1984-07-01

    Summary of the activities performed by the Heavy Water Projects Direction of the Argentine Atomic Energy Commission from 1950 to 1983. It covers: historical data; industrial plant (based on ammonia-hydrogen isotopic exchange); experimental plant (utilizing hydrogen sulfides-water process); Module-80 plant (2-3 tons per year experimental plant with national technology) and other related tasks on research and development (E.A.C.) [es

  2. Topical and working papers on heavy water requirements and availability

    International Nuclear Information System (INIS)

    The documents included in this report are: Heavy water requirements and availability; technological infrastructure for heavy water plants; heavy water plant siting; hydrogen and methane availability; economics of heavy water production; monothermal, water fed heavy water process based on the ammonia/hydrogen isotopic exchange; production strategies to meet demand projections; hydrogen availability; deuterium sources; the independent UHDE heavy water process

  3. Beam modulation for heavy ion radiotherapy

    International Nuclear Information System (INIS)

    Kanai, T.; Minohara, S.; Sudou, M.

    1993-01-01

    The first clinical trial of heavy ion radiation therapy is scheduled in 1994 by using the heavy ion medical accelerator in Chiba (HIMAC). In order to start the clinical trial, first, it is necessary to know the physical characteristics of high energy heavy ions in human bodies, for example, dose and linear energy transfer (LET) distribution. Also the knowledge on the biological effectiveness of heavy ions is required. Based on these biophysical properties of heavy ions, monoenergetic heavy ion beam should be modulated so as to make the spread Bragg peak suitable to heavy ion radiation therapy. In order to establish a methodology to obtain the most effective spread Bragg peak for heavy ion radiation therapy, a heavy ion irradiation port at the RIKEN ring cyclotron facility was constructed. By using a 135 MeV/u carbon beam, the biophysical properties of the heavy ions were investigated, and a range modulator was designed to have uniform biological response in the spread Bragg peak. The physical and biological rationality of the spread Bragg peak were investigated. The dose, LET and biological effect of a monoenergetic heavy ion beam, the design of the range modulator, and the distributions of LET and biological dose for the spread Bragg peak are reported. (K.I.)

  4. Progress Toward Heavy Ion IFE

    International Nuclear Information System (INIS)

    Meier, W.R.; Logan, B.G.; Waldron, W.L.; Sabbi, G.L.; Callahan-Miller, D.A.; Peterson, P.F.; Goodin, D.T.

    2002-01-01

    Successful development of Heavy Ion Fusion (HIF) will require scientific and technology advances in areas of targets, drivers and chambers. Design work on heavy ion targets indicates that high gain (60-130) may be possible with a -3-6 MJ driver depending on the ability to focus the beams to small spot sizes. Significant improvements have been made on key components of heavy ion drivers, including sources, injectors, insulators and ferromagnetic materials for long-pulse induction accelerator cells, solid-state pulsers, and superconducting quadrupole magnets. The leading chamber concept for HIF is the thick-liquid-wall HYLEE-II design, which uses an array of flibe jets to protect chamber structures from x-ray, debris, and neutron damage. Significant progress has been made in demonstrating the ability to create and control the types of flow needed to form the protective liquid blanket. Progress has also been made on neutron shielding for the final focus magnet arrays with predicted lifetimes now exceeding the life of the power plant. Safety analyses have been completed for the HYLEE-II design using state-of-the-art codes. Work also continues on target fabrication and injection for HE. A target injector experiment capable of > 5 Hz operation has been designed and construction will start in 2002. Methods for mass production of hohlraum targets are being evaluated with small-scale experiments and analyses. Progress in these areas will be reviewed

  5. Thorium in heavy water reactors

    International Nuclear Information System (INIS)

    Andersson, G.

    1984-12-01

    Advanced heavy water reactors can provide energy on a global scale beyond the foreseeable future. Their economic and safety features are promising: 1. The theoretical feasibility of the Self Sufficient Equilibrium Thorium (SSET) concept is confirmed by new calculations. Calculations show that the adjuster rod geometry used in natural uranium CANDU reactors is adequate also for SSET if the absorption in the rods is graded. 2. New fuel bundle designs can permit substantially higher power output from a CANDU reactor. The capital cost for fuel, heavy water and mechanical equipment can thereby be greatly reduced. Progress is possible with the traditional fuel material oxide, but the use of thorium metal gives much larger effects. 3. A promising long range possibility is to use pressure tanks instead of pressure tubes. Heat removal from the core is facilitated. Negative temperature and void coefficients provide inherent safety features. Refuelling under power is no longer needed if control by moderator displacement is used. Reduced quality demand on the fuel permits lower fuel costs. The neutron economy is improved by the absence of pressure and clandria tubes and also by the use of radial and axial blankets. A modular seed blanket design can reduce the Pa losses. The experience from construction of tank designs is good e.g. AAgesta, Attucha. It is now also possible to utilize technology from LWR reactors and the implementation of advanced heavy water reactors would thus be easier than HTR or LMFBR systems. (Author)

  6. Stable Heavy Hadrons in ATLAS

    CERN Document Server

    Mackeprang, Rasmus

    2007-01-01

    Several extensions to the SM feature heavy long-lived particles with masses of O(10^2-10^3 GeV) and mean lifetimes fulfilling $CT \\geq 10m$. Among such theories are supersymmetric scenarios as well as extra-dimensional models in which the heavy new particles are seen as Kaluza-Klein excitations of the well-known SM particles. Such particles will, from the point of view of a collider experiment be seen as stable. This thesis is concerned with the case where the exotic heavy particles emph{can} be considered stable while traversing the detector. Specifically the case is considered where the particles in question carry the charge of the strong nuclear force, commonly referred to as emph{colour charge}. A simulation kit has been developed using GEANT4. This framework is the current standard in experimental particle physics for the simulation of interactions of particles with matter, and it is used extensively for detector simulation. The simulation describes the interactions of these particles with matter which i...

  7. Fuel and heavy water availability

    International Nuclear Information System (INIS)

    1980-01-01

    The general guidelines for the Working Group's evaluation of the availability of nuclear fuel and heavy water were set at the Organizing Conference of the International Nuclear Fuel Cycle Evaluation (INFCE), which was held in Washington, United States of America, 19-21 October 1977. The agreed technical and economic scope for the evaluation was to: (1) Estimate needs for nuclear energy and correlated needs for uranium and heavy water according to different fuel cycle strategies; (2) Review uranium availability with specific regard to: Assessment of resources and production capacities; policies and incentives for encouraging exploration and production including joint ventures; marketing policies and/or guarantees of sales for companies investing in exploration and production; marketing policies and/or guarantees of supply for utilities; technical development of exploration, mining and milling methods; (3) Review heavy water availability; (4) Review thorium availability; (5) Consider special needs of developing countries. The illustrations of availability and requirements developed in this report do provide a useful framework for considering future options and alternatives for the development of nuclear power

  8. Nephrogenic systemic fibrosis: late skin manifestations

    DEFF Research Database (Denmark)

    Bangsgaard, Nannie; Marckmann, Peter; Rossen, Kristian

    2009-01-01

    BACKGROUND: Nephrogenic systemic fibrosis (NSF) is a serious disease that occurs in patients with severe renal disease and is believed to be caused by gadolinium-containing contrast agents. A detailed description of the late skin manifestations of NSF is important to help dermatologists...... and nephrologists recognize the disease. OBSERVATIONS: We studied 17 patients with NSF late in the disease. All patients showed epidermal atrophy and hairlessness of the affected regions, primarily the lower legs. Affected areas were symmetrically distributed and hyperpigmented in most cases. Eleven patients showed......: This descriptive case series of patients with NSF gives a detailed clinical picture of the skin manifestations late in the disease. It demonstrates that the clinical picture in the late stage has a varied presentation and that NSF has a significant effect on the quality of life....

  9. Late onset depression: A recent update

    Directory of Open Access Journals (Sweden)

    Ananya Mahapatra

    2015-01-01

    Full Text Available Late onset depression has recently emerged as a serious mental health issue in the geriatric population with significant public health implications. It is often challenging to diagnose and treat this entity. Various theories have been postulated to elucidate the etiology of late onset depression, but a unifying hypothesis is lacking. Although the vascular hypothesis is most researched; a complex interaction of multiple vulnerability factors is the current focus of attention. Numerous psychosocial variables have been implicated to play a significant role in predicting the onset and severity of late-life depression. Phenomenological differences have been delineated from depression occurring at a younger age, but the findings are equivocal. A better understanding of the natural trajectory of depression in the elderly is required for early diagnosis and effective treatment. This review attempts to summarize the current status of evidence regarding epidemiology, etiology, clinical features, and treatment options available for late-onset depression.

  10. Early- and Late-Onset Inherited Erythromelalgia

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2009-08-01

    Full Text Available A genotype-phenotype relationship at the clinical, cellular and molecular levels is shown in a case of erythromelalgia of relatively late onset, in a study at Yale University School of Medicine, and centers in China.

  11. Progression of Late-Onset Stargardt Disease

    OpenAIRE

    Lambertus, Stanley; Lindner, Moritz; Bax, Nathalie M.; Mauschitz, Matthias M.; Nadal, Jennifer; Schmid, Matthias; Schmitz-Valckenberg, Steffen; den Hollander, Anneke I.; Weber, Bernhard H. F.; Holz, Frank G.; van der Wilt, Gert Jan; Fleckenstein, Monika; Hoyng, Carel B.

    2016-01-01

    Purpose: Identification of sensitive biomarkers is essential to determine potential effects of emerging therapeutic trials for Stargardt disease. This study aimed to describe the natural history of late-onset Stargardt, and demonstrates the accuracy of retinal pigment epithelium (RPE) atrophy progression as an outcome measure. Methods: We performed a retrospective cohort study collecting multicenter data from 47 patients (91 eyes) with late-onset Stargardt, defined by clinical phenotype...

  12. Posttraumatic syringomyelia associated with heavy weightlifting exercises: case report.

    Science.gov (United States)

    Balmaseda, M T; Wunder, J A; Gordon, C; Cannell, C D

    1988-11-01

    Posttraumatic syringomyelia is a well-recognized late sequel to spinal trauma occurring in 1% to 3.2% of spinal cord injured patients. Its clinical presentation is usually marked by pain, ascending sensory loss, increased muscle weakness, and depressed deep tendon reflexes. The case of a 25-year-old man with C8 complete quadriplegia, who developed a syrinx five years after his initial injury, is presented. This patient kept a log of his daily physical workout which consisted of lifting weights of 50 to 60 pounds with his neck extensors and biceps. The diagnosis was made clinically and confirmed by magnetic resonance imaging. Repeated valsalva maneuvers from daily heavy weightlifting exercises most likely predisposed this patient to the development and extension of his syringomyelia. Dramatic improvement followed surgical placement of a subarachnoid shunt.

  13. Drying of heavy water system and works of charging heavy water in Fugen

    International Nuclear Information System (INIS)

    Matsushita, Tadashi; Iijima, Setsuo

    1980-01-01

    The advanced thermal reactor ''Fugen'' is the first heavy water-moderated, boiling light water-cooled nuclear reactor for power generation in Japan. It is a large heavy water reactor having about 130 m 3 of heavy water inventory and about 300 m 3 of helium space as the cover gas of the heavy water system. The heavy water required was purchased from FRG, which had been used for the power output test in the KKN, and the quality was 99.82 mol % mean heavy water concentration. The concentration of heavy water for Fugen used for the nuclear design is 99.70 mol%, and it was investigated how heavy water can be charged without lowering the concentration. The matters of investigation include the method of bringing the heavy water and helium system to perfect dryness after washing and light water test, the method of confirming the sufficient dryness to prevent the deterioration, and the method of charging heavy water safely from its containers. On the basis of the results of investigation, the actual works were started. The works of drying the heavy water and helium system by vacuum drying, the works of sampling heavy water and the result of the degree of deterioration, and the works of charging heavy water and the measures to the heavy water remaing in the containers are described. All the works were completed safely and smoothly. (J.P.N.)

  14. Quantification of late complications after radiation therapy

    International Nuclear Information System (INIS)

    Jung, Horst; Beck-Bornholdt, Hans-Peter; Svoboda, Vladimir; Alberti, Winfried; Herrmann, Thomas

    2001-01-01

    Background: An increasing number of patients survive cancer after having received radiation therapy. Therefore, the occurrence of late normal tissue complications among long-term survivors is of particular concern. Methods: Sixty-three patients treated by radical surgery and irradiation for rectal carcinoma were subjected to an unconventional sandwich therapy. Preoperative irradiation was given in four fractions of 5 Gy each applied within 2 or 3 days; postoperative irradiation consisted mostly of 15x2 Gy (range, 20-40 Gy). A considerable proportion of these patients developed severe late complications (Radiother Oncol 53 (1999) 177). The data allowed a detailed analysis of complication kinetics, leading to a new model which was tested using data from the literature. Results: Data on late complications were obtained for eight different organs with a follow-up of up to 10 years. For the various organs, the percentage of patients being free from late complications, plotted as a function of time after start of radiation therapy, was adequately described by exponential regression. From the fit, the parameter p a was obtained, which is the percentage of patients at risk in a given year of developing a complication in a given organ during that year. The rate p a remained about constant with time. Following sandwich therapy, the annual incidence of complications in the bladder, ileum, lymphatic and soft tissue, and ureters was about the same (p a =10-14%/year), whereas complications in bone or dermis occurred at lower rates (4.7 or 7.5%/year, respectively). Discussion: Numerous data sets collected from published reports were analyzed in the same way. Many of the data sets studied were from patients in a series where there was a high incidence of late effects. Three types of kinetics for the occurrence of late effects after radiotherapy were identified: Type 1, purely exponential kinetics; Type 2, exponential kinetics, the slope of which decreased exponentially with time

  15. Biosolids and heavy metals in soils

    Directory of Open Access Journals (Sweden)

    Silveira Maria Lucia Azevedo

    2003-01-01

    Full Text Available The application of sewage sludge or biosolids on soils has been widespread in agricultural areas. However, depending on their characteristics, they may cause increase in heavy metal concentration of treated soils. In general, domestic biosolids have lower heavy metal contents than industrial ones. Origin and treatment method of biosolids may markedly influence their characteristics. The legislation that controls the levels of heavy metal contents in biosolids and the maximum concentrations in soils is still controversial. In the long-term, heavy metal behavior after the and of biosolid application is still unknown. In soils, heavy metals may be adsorbed via specific or non-specific adsorption reactions. Iron oxides and organic matter are the most important soil constituents retaining heavy metals. The pH, CEC and the presence of competing ions also affect heavy metal adsorption and speciation in soils. In solution, heavy metals can be present either as free-ions or complexed with organic and inorganic ligands. Generally, free-ions are more relevant in environmental pollution studies since they are readily bioavailable. Some computer models can estimate heavy metal activity in solution and their ionic speciation. Thermodynamic data (thermodynamic stability constant, total metal and ligand concentrations are used by the GEOCHEM-PC program. This program allows studying heavy metal behavior in solution and the effect of changes in the conditions, such as pH and ionic strength and the application of organic and inorganic ligands caused by soil fertilization.

  16. Historical trend in heavy metal pollution in core sediments from the Masan Bay, Korea.

    Science.gov (United States)

    Cho, Jinhyung; Hyun, Sangmin; Han, J-H; Kim, Suhyun; Shin, Dong-Hyeok

    2015-06-15

    The spatiotemporal distribution and their mass accumulation rate (MAR) of heavy metals were investigated to evaluate the time-dependent historical trends of heavy metal concentration. The three short cores used for this study were collected from the catchment area (MS-PC5, 60cm length), the central part (MS-PC4, 40cm length) and the offshore (MS-PC2, 60cm length) of the Masan Bay, Korea. The concentration of heavy metals (Co, Ni, Cu, Zn, Cr and Pb) in catchment area is as much as 1.5-2 times higher than central part of the Bay, and about 2 times higher than offshore area approximately. In particular, MAR of metals (Cu, Zn and Pb) show clear spatiotemporal variation, so that MAR's of heavy metal may provide more accurate information in evaluating the degree of pollution. Temporally, the heavy metal concentration had been increased since the late 1970s, but it seems to decrease again since the 2004yr in catchment area. This may came from concentrated efforts for the government to reduce industrial waste release. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. DNA damage and repair in oncogenic transformation by heavy ion radiation

    Science.gov (United States)

    Yang, T. C.; Mei, M.; George, K. A.; Craise, L. M.

    1996-01-01

    Energetic heavy ions are present in galactic cosmic rays and solar particle events. One of the most important late effects in risk assessment is carcinogenesis. We have studied the carcinogenic effects of heavy ions at the cellular and molecular levels and have obtained quantitative data on dose-response curves and on the repair of oncogenic lesions for heavy particles with various charges and energies. Studies with repair inhibitors and restriction endonucleases indicated that for oncogenic transformation DNA is the primary target. Results from heavy ion experiments showed that the cross section increased with LET and reached a maximum value of about 0.02 micrometer2 at about 500 keV/micrometer. This limited size of cross section suggests that only a fraction of cellular genomic DNA is important in radiogenic transformation. Free radical scavengers, such as DMSO, do not give any effect on induction of oncogenic transformation by 600 MeV/u iron particles, suggesting most oncogenic damage induced by high-LET heavy ions is through direct action. Repair studies with stationary phase cells showed that the amount of reparable oncogenic lesions decreased with an increase of LET and that heavy ions with LET greater than 200 keV/micrometer produced only irreparable oncogenic damage. An enhancement effect for oncogenic transformation was observed in cells irradiated by low-dose-rate argon ions (400 MeV/u; 120 keV/micrometer). Chromosomal aberrations, such as translocation and deletion, but not sister chromatid exchange, are essential for heavy-ion-induced oncogenic transformation. The basic mechanism(s) of misrepair of DNA damage, which form oncogenic lesions, is unknown.

  18. Superconducting heavy-ion linacs

    International Nuclear Information System (INIS)

    Bollinger, L.M.

    1977-01-01

    A summary is given of plans developed by four different groups for the construction of small superconducting linacs to boost the energy of heavy ions from existing tandem electrostatic accelerators. The projects considered are the linac under construction at Argonne and the design efforts at Karlsruhe, at Stanford, and by a Cal Tech-Stony Brook collaboration. The intended uses of the accelerator systems are stated. Beam dynamics of linacs formed of short independently-phased resonators are reviewed, and the implications for performance are discussed. The main parameters of the four linacs are compared, and a brief analysis of accelerating structures is given

  19. Muon studies of heavy fermions

    International Nuclear Information System (INIS)

    Heffner, R.H.

    1991-01-01

    Recent muon spin relaxation (μSR) studies have been particularly effective in revealing important properties of the unusual magnetism and superconductivity found in heavy fermion (HF) systems. In this paper μSR experiments elucidating the symmetry of superconducting order parameter in UPt 3 and UBe 13 doped with thorium and reviewed. Also discussed is the correlation between the enhanced superconducting specific heat jump and the reduced Kondo temperature in B-doped UBe 13 , indicating possible direct experimental evidence for a magnetic pairing mechanism in HF superconductors. 23 refs., 3 figs

  20. Neutron moderation in heavy water

    International Nuclear Information System (INIS)

    Assis, J.T. de.

    1980-03-01

    The calculation of the energetic spectrum of thermic neutrons in heavy water, according to the models of the differential cross section; is presented. Simplifications in the Butler model are suggested for the diminution of computer time. The results obtained are compared with experimental data and with the Brown - St.John model. This calculation has been done in 30 energy groups and within our limit of precision, the results with the models and simplifications present satisfactory values, allowing its inclusion in reactor codes. (Author) [pt

  1. Nucleon transfer between heavy nuclei

    International Nuclear Information System (INIS)

    Von Oertzen, W.

    1984-02-01

    Nucleon transfer reactions between heavy nuclei are characterized by the classical behaviour of the scattering orbits. Thus semiclassical concepts are well suited for the description of these reactions. In the present contribution the characteristics of single and multinucleon transfer reactions at energies below and above the Coulomb barrier are shown for systems like Sn+Sn, Xe+U and Ni+Pb. The role of the pairing interaction in the transfer of nucleon pairs is illustrated. For strong transitions the coupling of channels and the absorption into more complicated channels is taken into account in a coupled channels calculation

  2. Heavy flavour decays at LEP

    CERN Document Server

    Rousseau, D H

    2001-01-01

    Recent heavy flavour results from LEP experiments are presented. Special emphasis is put on complex inclusive B reconstruction methods with high potentialities for lifetime, mixing, CP violation studies and new measurements of IVubl· The new world average of r8-f'r8o is 1.08 ± 0.03. The new world average of Re parameter measured in inclusive B0 decay is 0.001 ± 0.009. The new LEP average of JV ub I measured from inclusive b->ulv branching fraction is 4.

  3. Lifetimes of heavy flavour particles

    International Nuclear Information System (INIS)

    Forty, R.

    1994-01-01

    The lifetimes of heavy-flavour hadrons are reviewed. After a brief discussion of the theoretical predictions, the problem of averaging lifetime measurements is discussed. The various experimental measurements are then presented and suitable averages performed. Charmed meson lifetimes are now measured to the few percent level, better that theory can predict, whilst for charmed baryons the lifetime hierarchy has been established for the first time. For beauty hadrons the lifetimes are measured at the 6-10 % level, and are in reasonable agreement with theoretical expectations. Beauty baryon studies ar just beginning. (author)

  4. Heavy meson form factors from QCD

    International Nuclear Information System (INIS)

    Falk, A.F.; Georgi, H.; Grinstein, B.

    1990-01-01

    We calculate the leading QCD radiative corrections to the relations which follow from the decoupling of the heavy quark spin as the quark mass goes infinity and from the symmetry between systems with different heavy quarks. One of the effects we calculate gives the leading q 2 -dependence of the form factor of a heavy quark, which in turn dominates the q 2 -dependence of the form factors of bound states of the heavy quark with light quarks. This, combined with the normalization of the form factor provided by symmetry, gives us a first principles calculation of the heavy meson (or baryon) form factors in the limit of very large heavy quark mass. (orig.)

  5. Oil Spill Related Heavy Metal: A Review

    International Nuclear Information System (INIS)

    Ahmad Dasuki Mustafa; Hafizan Juahir; Kamaruzzaman Yunus; Mohammad Azizi Amran; Che Noraini Che Hasnam; Fazureen Azaman; Ismail Zainal Abidin; Syahril Hirman Azmee; Nur Hishaam Sulaiman

    2015-01-01

    Oil spill occurs every day worldwide and oil contamination is a significant contributor for the higher levels of heavy metals in the environment. This study is purposely to summarize the heavy metals which significant to major oil spill incidents around the world and effects of toxic metals to human health. The study performed a comprehensive review of relevant scientific journal articles and government documents concerning heavy metals contamination and oil spills. Overall, the heavy metals most frequently been detected in oil spill related study where Pb>Ni>V>Zn>Cd and caused many effects to human health especially cancer. In conclusion, the comparison of heavy metal level between the post - spill and baseline levels must be done, and implementation of continuous monitoring of heavy metal. In addition, the result based on the strategies must be transparent to public in order to maintaining human health. (author)

  6. Heavy Water Quality Management in HANARO

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Ho Chul; Lee, Mun; Kim, Hi Gon; Park, Chan Young; Choi, Ho Young; Hur, Soon Ock; Ahn, Guk Hoon

    2008-12-15

    Heavy water quality management in the reflector tank is a very important element to maintain the good thermal neutron flux and to ensure the performance of reflector cooling system. This report is written to provide a guidance for the future by describing the history of the heavy water quality management during HANARO operation. The heavy water quality in the reflector tank has been managed by measuring the electrical conductivity at the inlet and outlet of the ion exchanger and by measuring pH of the heavy water. In this report, the heavy water quality management activities performed in HANARO from 1996 to 2007 ere described including a basic theory of the heavy water quality management, exchanging history of used resin in the reflector cooling system, measurement data of the pH and the electrical conductivity, and operation history of the reflector cooling system.

  7. Paradox of Prescribing Late Chemotherapy: Oncologists Explain.

    Science.gov (United States)

    Bluhm, Minnie; Connell, Cathleen M; De Vries, Raymond G; Janz, Nancy K; Bickel, Kathleen E; Silveira, Maria J

    2016-12-01

    The value of chemotherapy for patients with cancer in the last weeks of life warrants examination. Late chemotherapy may not improve survival or quality of life but typically precludes hospice enrollment and may result in additional symptoms, increased use of other aggressive treatments, and worsening quality of life. Few studies have explored oncologists' rationales for administering chemotherapy near death. This study examines the self-reported factors that influence oncologists' decisions about late chemotherapy. In-depth individual interviews were conducted with 17 oncologists through a semistructured interview guide. Interviews were audio recorded and transcribed verbatim. Transcripts were coded and analyzed using conventional content analysis, a qualitative method that allows the detection and analysis of patterns in the data. Clinical factors take priority in determining late chemotherapy decisions when clear treatment choices exist. When clinical factors are ambiguous, emotion becomes a highly salient influence. Oncologists view late chemotherapy to be patient driven and use it to palliate emotional distress and maintain patient hope even when physical benefit is unexpected. Oncologists experience unique and difficult challenges when caring for dying patients, including emotionally draining communication, overwhelming responsibility for life/death, limitations of oncology to heal, and prognostic uncertainty. These challenges are also eased by offering late chemotherapy. The findings reveal a nuanced understanding of why oncologists find it difficult to refuse chemotherapy treatment for patients near death. Optimal end-of-life treatment decisions require supportive interventions and system change, both of which must take into account the challenges oncologists face.

  8. The polyimage poetics in Ibsen's late plays

    Directory of Open Access Journals (Sweden)

    Wang Yuli

    2015-02-01

    Full Text Available The unique poetics of polyimage implied in Ibsen’s late plays can be excavated with aesthetic reading. The term polyimage is coined to describe Ibsen’s original design in aesthetic form and ingenious realm in aesthetic reaction in his late plays; that is, beyond an imagery realm, another imagery realm exists, which construct a deep vision of significance. In each of the excellent late plays, what Ibsen creates is one or more veiled holistic imagery realms in addition to an ordinary entire imagery realm perceived by most audiences. The “layers of imagery realm” result from Ibsen’s “double self-examinations”, including self-examination of soul and of art. It is these “double self-examinations” that make polyimage possible in his late plays and generates the attribute of “meta-art” in these works. Compared with polyphony in Dostoevsky’s novels, the polyimage in Ibsen’s late plays contains a unique modernity, which is of great significance to modern artistic creation.

  9. Pathological review of late cerebral radionecrosis

    International Nuclear Information System (INIS)

    Yoshii, Yoshihiko

    2008-01-01

    Late cerebral radionecrosis may be considered to be a specific chronic inflammatory response, although it is unknown whether the initial damage by brain irradiation is to an endothelial cell or a glial cell. I discuss the pathological specificity of late cerebral radionecrosis by studying the published literature and a case that I experienced. In late cerebral radionecrosis, there are typical coagulation necrosis areas containing fibrinoid necrosis with occlusion of the lumina and poorly active inflammatory areas with many inflammatory ghost cells, focal perivascular lymphocytes, hyalinized vessels, and telangiectatic vascularization near and in the necrotic tissue, and more active inflammatory areas formed as a partial rim of the reactive zone by perivascular lymphocytes, much vascularization, and glial fibrillary acidic protein (GFAP)-positive astrocytes at the corticomedullary border adjacent to necrotic tissue in the white matter. It is difficult to believe that coagulation necrosis occurs without first disordering the vascular endothelial cells because fibrinoid necrosis is a main feature and a diffusely multiple lesion in late cerebral radionecrosis. Because various histological findings do develop, progress, and extend sporadically at different areas and times in the irradiated field of the brain for a long time after radiation, uncontrolled chronic inflammation containing various cytokine secretions may also play a key role in progression of this radionecrosis. Evaluation of the mechanism of the development/aggravation of late cerebral radionecrosis requires a further study for abnormal cytokine secretions and aberrant inflammatory reactions. (author)

  10. Heavy flavour production in perturbative QCD

    International Nuclear Information System (INIS)

    Nason, P.; Ridolfi, G.; Frixione, S.; Mangano, M.L.

    1994-01-01

    The status of heavy flavour production in QCD is reviewed. Recent results on the doubly-differential cross section are discussed for the photoproduction of heavy flavours. Comparison of experimental results with theoretical calculation is discussed both for b production at hadron colliders and c production in fixed-target hadroproduction and photoproduction. The possibility of using photoproduction of heavy flavour in order to determine the gluon density in the proton is also discussed. (author). 38 refs., 8 figs

  11. Summary of the relativistic heavy ion sessions

    International Nuclear Information System (INIS)

    Harris, J.W.

    1988-01-01

    The topics covered in the Relativistic Heavy Ion Sessions span four orders of magnitude in energy in the laboratory and a few more in theory. In the two years since the last Intersections conference, experiments in the field of very high energy heavy ion research have begun at CERN and Brookhaven. The prime motivation for these experiments is the possibility of forming quark matter. This paper is a review of the topics covered in the Relativistic Heavy Ion Sessions

  12. International cooperation in heavy-ion research

    International Nuclear Information System (INIS)

    Tobias, C.A.

    1980-01-01

    The rapidly growing research applications of heavy ions in basic biology and medicine have stimulated interest in this field in many countries. LBL, with its unique facilities and its scientific programs, is the focal point of interest. Plans are underway in several countries, including France, Japan, West Germany, and Canada, to build heavy-ion facilities, and to collaborate with our staff at LBL in heavy-ion research in physics, biology, and medicine

  13. Heavy vehicle pitch dynamics and suspension tuning

    OpenAIRE

    Cao, Dongpu; Rakheja, Subhash; Su, Chun-Yi

    2008-01-01

    The influence of suspension tuning of passenger cars on bounce and pitch ride performance has been explored in a number of studies, while only minimal efforts have been made for establishing similar rules for heavy vehicles. This study aims to explore pitch dynamics and suspension tunings of a two-axle heavy vehicle with unconnected suspension, which could also provide valuable information for heavy vehicles with coupled suspensions. Based on a generalised pitch-plane model of a two-axle heav...

  14. The Heavy Baryon Physics by means LEP

    International Nuclear Information System (INIS)

    Lesiak, T.

    2000-07-01

    This report describes the experimental research about the heavy baryons which were obtained in the last decade at LEP. The most important among them concern the lifetimes of beauty baryons. The methods of theoretical description of heavy hadrons together with the LEP experimental apparatus are also discussed. Heavy baryon studies are shown in a broader perspective of other LEP results: the test of the standard model and the latest measurements concerning the beauty mesons. (author)

  15. Heavy quarks and their experimental consequences

    International Nuclear Information System (INIS)

    Appelquist, T.

    1975-09-01

    Recent theoretical work on heavy quark dynamics is reviewed. In the context of a color gauge theory of strong interactions, the structure of heavy quark-antiquark bound states and their decay properties is discussed. The emphasis is on the dynamical differences between heavy and light quark bound states. It is suggested that the former will more directly reflect the structure of the underlying field theory

  16. Heat exchangers in heavy water reactor systems

    International Nuclear Information System (INIS)

    Mehta, S.K.

    1988-01-01

    Important features of some major heat exchange components of pressurized heavy water reactors and DHRUVA research reactor are presented. Design considerations and nuclear service classifications are discussed

  17. Heavy quark production in quantum chromodynamics

    International Nuclear Information System (INIS)

    Brodsky, S.J.

    1986-09-01

    For very heavy quark masses, the inclusive hadronic production of hadron pairs containing heavy quarks is predicted to be governed by QCD fusion subprocesses. For intermediate mass scales other QCD mechanisms can be important including higher-twist intrinsic contributions and low relative velocity enchancements, possibly accounting for the anomalies observed in charm hadroproduction, such as the nuclear number dependence, the longitudinal momentum distributions, and beam flavor dependence. We also discuss scaling laws for exclusive processes involving heavy quarks and diffractive excitation into heavy quark systems

  18. Production of heavy water in India

    International Nuclear Information System (INIS)

    Deshpande, P.G.; Bimbhat, K.S.; Bhargava, R.K.

    India's first heavy water plant, using electrolysis of water followed by liquid hydrogen distillation, has been operating in association with a fertilizer plant at Nangal since 1962. A dual-temperature process plant at Kota uses heat from the Rajasthan Atomic Power Station. The heavy water plants at Baroda and Tuticorin use ammonia-hydrogen exchange and are integrated with fertilizer ammonia plants. Choice of a particular process for heavy water production depends upon local conditions as well as the extent of the heavy water requirement

  19. Divergent biology of facultative heavy metal plants.

    Science.gov (United States)

    Bothe, Hermann; Słomka, Aneta

    2017-12-01

    Among heavy metal plants (the metallophytes), facultative species can live both in soils contaminated by an excess of heavy metals and in non-affected sites. In contrast, obligate metallophytes are restricted to polluted areas. Metallophytes offer a fascinating biology, due to the fact that species have developed different strategies to cope with the adverse conditions of heavy metal soils. The literature distinguishes between hyperaccumulating, accumulating, tolerant and excluding metallophytes, but the borderline between these categories is blurred. Due to the fact that heavy metal soils are dry, nutrient limited and are not uniform but have a patchy distribution in many instances, drought-tolerant or low nutrient demanding species are often regarded as metallophytes in the literature. In only a few cases, the concentrations of heavy metals in soils are so toxic that only a few specifically adapted plants, the genuine metallophytes, can cope with these adverse soil conditions. Current molecular biological studies focus on the genetically amenable and hyperaccumulating Arabidopsis halleri and Noccaea (Thlaspi) caerulescens of the Brassicaceae. Armeria maritima ssp. halleri utilizes glands for the excretion of heavy metals and is, therefore, a heavy metal excluder. The two endemic zinc violets of Western Europe, Viola lutea ssp. calaminaria of the Aachen-Liège area and Viola lutea ssp. westfalica of the Pb-Cu-ditch of Blankenrode, Eastern Westphalia, as well as Viola tricolor ecotypes of Eastern Europe, keep their cells free of excess heavy metals by arbuscular mycorrhizal fungi which bind heavy metals. The Caryophyllaceae, Silene vulgaris f. humilis and Minuartia verna, apparently discard leaves when overloaded with heavy metals. All Central European metallophytes have close relatives that grow in areas outside of heavy metal soils, mainly in the Alps, and have, therefore, been considered as relicts of the glacial epoch in the past. However, the current

  20. Heavy oil in Saskatchewan: Building on strengths

    International Nuclear Information System (INIS)

    1994-02-01

    Saskatchewan has reserves of 17.6 billion bbl of heavy oil located in the west-central part of the province. The first oil well was drilled in 1945 and production of heavy oil has increased gradually, reaching 79,000 bbl/d in 1992. In recent years, the production pattern has not matched trends in investment; since 1982/83, the relative proportion of heavy oil drilling has declined significantly. A study is presented which analyzes trends in heavy oil investment, production, economics, and markets, with a focus on determining the causes for lack of investment in the heavy oil sector and evaluating the opportunities and constraints for long-term sustainability of this industry. Industry background is provided, with presentation of the key resource characteristics, reserve potential, and production and investment trends. Markets both in Canada and the USA are analyzed in detail, possible future trends are suggested. The effect of development of refinery capacity on heavy oil developments is examined. The logistics of shipping heavy oil to markets are detailed. The economics of Saskatchewan heavy oil production are established, taking into account all relevant cost components including taxes, royalties, and netbacks to producers. Issues of relevance affecting the heavy oil industry are discussed, including the need for environmental safeguards. 25 figs., 24 tabs

  1. Heavy water moderated tubular type nuclear reactor

    International Nuclear Information System (INIS)

    Oohashi, Masahisa.

    1986-01-01

    Purpose: To enable to effectively change the volume of heavy water per unit fuel lattice in heavy water moderated pressure tube type nuclear reactors. Constitution: In a nuclear reactor in which fuels are charged within pressure tubes and coolants are caused to flow between the pressure tubes and the fuels, heavy water tubes for recycling heavy water are disposed to a gas region formed to the outside of the pressure tubes. Then, the pressure tube diameter at the central portion of the reactor core is made smaller than that at the periphery of the reactor core. Further, injection means for gas such as helium is disposed to the upper portion for each of the heavy water tubes so that the level of the heavy water can easily be adjusted by the control for the gas pressure. Furthermore, heavy water reflection tubes are disposed around the reactor core. In this constitution, since the pitch for the pressure tubes can be increased, the construction and the maintenance for the nuclear reactor can be facilitated. Also, since the liquid surface of the heavy water in the heavy water tubes can be varied, nuclear properties is improved and the conversion ratio is improved. (Ikeda, J.)

  2. Dynamical limitations to heavy ion fusion

    International Nuclear Information System (INIS)

    Back, B.B.

    1983-01-01

    Dynamical limitations to heavy ion fusion reaction are considered. The experimental signatures and the importance of a quasi-fission process are examined. The anaular distributions of fission fragments for the 32 S+ 208 Pb and 16 O+ 238 U systems are presented. It is shown that the observations of quasi-fission for even rather ''light'' heavy ions poeess severe limitations on the fusion process. This result may consequently be responsible for the lack of success of the search for super heavy elements in heavy ion fusion reactions

  3. Poisoning of domestic animals with heavy metals

    Directory of Open Access Journals (Sweden)

    Velev Romel

    2009-01-01

    Full Text Available The term heavy metal refers to a metal that has a relatively high density and is toxic for animal and human organism at low concentrations. Heavy metals are natural components of the Earth's crust. They cannot be degraded or destroyed. To a small extent they enter animal organism via food, drinking water and air. Some heavy metals (e.g cooper, iron, chromium, zinc are essential in very low concentrations for the survival of all forms of life. These are described as essential trace elements. However, when they are present in greater quantities, like the heavy metals lead, cadmium and mercury which are already toxic in very low concentrations, they can cause metabolic anomalies or poisoning. Heavy metal poisoning of domestic animals could result, for instance, from drinking-water contamination, high ambient air concentrations near emission sources, or intake via the food chain. Heavy metals are dangerous because they tend to bioaccumulate in a biological organism over time. Manifestation of toxicity of individual heavy metals varies considerably, depending on dose and time of exposure, species, gender and environmental and nutritional factors. Large differences exist between the effects of a single exposure to a high concentration, and chronic exposures to lower doses. The aim of this work is to present the source of poisoning and toxicity of some heavy metals (lead, mercury, cadmium, thallium, arsenic, as well as new data about effects of those heavy metals on the health of domestic animals. .

  4. A decade of heavy light

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Ten years ago, in May 1983, the UA1 experiment led by Carlo Rubbia at CERN's proton-antiproton collider saw the first Z particle, the heavy (91 GeV) electrically neutral carrier of the weak force. The press announced the discovery of 'heavy light', a highly apt description which has unfortunately fallen into disuse. The weak force comes in two varieties - one which permutes electric charges (the classic example being the beta decay of a neutron into a proton and an electron), and a neutral variant which does not. Each has its carrier particle, and both were discovered at CERN - first the charged W, in January 1983, and then the Z, a few months later. For both experiment and theory, the Z discovery was the culmination of a long and diligent quest without parallel in the history of modern physics. The missing piece of the 'electroweak' jigsaw finally clicked into place, and for ever after electromagnetism would be firmly linked with the weak nuclear force. It was the twentieth-century remake, with a much bigger cast, of the story which began in 1864 when James Clerk Maxwell wrote down his four famous equations linking electricity and magnetism. This was the birth of a new science - electromagnetism

  5. Heavy spin-2 Dark Matter

    Energy Technology Data Exchange (ETDEWEB)

    Babichev, Eugeny [Laboratoire de Physique Théorique, CNRS, Univ. Paris-Sud, Université Paris-Saclay,91405 Orsay (France); UPMC-CNRS, UMR7095, Institut d’Astrophysique de Paris, GReCO,98bis boulevard Arago, F-75014 Paris (France); Marzola, Luca; Raidal, Martti [National Institute of Chemical Physics and Biophysics,Rävala 10, 10143 Tallinn (Estonia); Laboratory of Theoretical Physics, Institute of Physics, University of Tartu,Ravila 14c, 50411 Tartu (Estonia); Schmidt-May, Angnis [Institut für Theoretische Physik, Eidgenössische Technische Hochschule Zürich,Wolfgang-Pauli-Strasse 27, 8093 Zürich (Switzerland); Urban, Federico; Veermäe, Hardi [National Institute of Chemical Physics and Biophysics,Rävala 10, 10143 Tallinn (Estonia); Strauss, Mikael von [UPMC-CNRS, UMR7095, Institut d’Astrophysique de Paris, GReCO,98bis boulevard Arago, F-75014 Paris (France)

    2016-09-12

    We provide further details on a recent proposal addressing the nature of the dark sectors in cosmology and demonstrate that all current observations related to Dark Matter can be explained by the presence of a heavy spin-2 particle. Massive spin-2 fields and their gravitational interactions are uniquely described by ghost-free bimetric theory, which is a minimal and natural extension of General Relativity. In this setup, the largeness of the physical Planck mass is naturally related to extremely weak couplings of the heavy spin-2 field to baryonic matter and therefore explains the absence of signals in experiments dedicated to Dark Matter searches. It also ensures the phenomenological viability of our model as we confirm by comparing it with cosmological and local tests of gravity. At the same time, the spin-2 field possesses standard gravitational interactions and it decays universally into all Standard Model fields but not into massless gravitons. Matching the measured DM abundance together with the requirement of stability constrains the spin-2 mass to be in the 1 to 100 TeV range.

  6. Radiobiology of heavy charged particles

    International Nuclear Information System (INIS)

    Kraft, G.

    1996-11-01

    The increase in the biological efficiency is the major motivation to use ions heavier than protons for therapy. Therefore, the detailed understanding of the radiobiological potential of heavy ions like carbon or oxygen is the basic condition of a proper application of these ions in therapy. But also for the lightest ion, the proton, evidence accumulates that changes in the radiobiological properties at the end of the particle range influence the therapeutic effect. Compared to sparsely ionizing radiation heavy charged particles exhibit a different physical interaction with the target material: The highly charged ions interact mostly via Coulomb forces with the electrons of the target material producing a track of ionizations and highly kinetic electrons along the path of the primary ion. In these tracks damage to the biological structures like the DNA occurs in a non stochastic, but spatially correlated way yielding a dramatic variation in the biological severity of the created damage. In cell-experiments the variation in the relative biological efficiency has been measured for many biological reactions like cell inactivation, chromosome aberrations and DNA damage. An overview on the inactivation data will be given and theoretical approaches will be discussed and compared to experimental data. (orig.)

  7. Heavy Ion Physics at CMS

    CERN Document Server

    Veres, Gabor

    2017-01-01

    In the present proceedings recent heavy ion results from the Compact Muon Solenoid collaboration at the LHC are presented. These contain comparisons between small and large collision systems, as well as studies of energy evolution, thus include data collected in proton-proton collisions at 13 TeV (2015 and 2016), proton-proton and lead-lead collisions at 5 TeV (2015), and proton-lead collisions at 5 TeV and 8 TeV (2016) center-of-mass energy per nucleon pair. They provide new insights into the properties of the extremely high density and high temperature matter created in heavy ion collisions, while pointing out similarities and differences in comparison to smaller collision systems. These include gluon distribution functions in the lead nucleus; the azimuthal anisotropy of final state particle distributions in all the three different collision systems; charge separation signals from proton-lead collisions and consequences for the Chiral Magnetic Effect; new studies of parton energy loss and its dependence on...

  8. Early- versus Late-Onset Dysthymia

    Science.gov (United States)

    Sansone, Lori A.

    2009-01-01

    In the current Diagnostic and Statistical Manual of Mental Disorders, dysthymic disorder is categorized as either early-onset or late-onset, based upon the emergence of symptoms before or after the age of 21, respectively. Does this diagnostic distinction have any meaningful clinical implications? In this edition of The Interface, we present empirical studies that have, within a single study, compared individuals with early-versus late-onset dysthymia. In this review, we found that, compared to those with late-onset dysthymia, early-onset patients are more likely to harbor psychiatric comorbidity both on Axis I and II, exhibit less psychological resilience, and have more prominent family loadings for mood disorders. These findings suggest that this distinction is meaningful and that the early-onset subtype of dysthymia is more difficult to effectively treat. PMID:20049145

  9. Mobile ICT Acceptance in Late Adopter Countries

    DEFF Research Database (Denmark)

    Gimpel, Gregory; Sudzina, Frantisek; Petrovcikova, Katarina

    2014-01-01

    Despite the rapid global diffusion of the smartphone, some countries have experienced much slower uptake of the technology. The low smartphone penetration within Slovakia provides the opportunity to explore what drives smartphone use in late majority countries. Slovakia is a central European nation...... and part of the Eurozone. It has advanced telecommunications infrastructure and is subject to the same telecommunications regulations as other EU members. While neighbours have high smartphone penetration, Slovakia is a late majority adopter. This study uses Triandis’ theory of interpersonal behavior...... to investigate the question: What drives the use of smartphones in late majority countries? By studying the differences between current and potential smartphone users, the study revisits Karahanna et al.’s research question: Do potential adopters and users of IT hold the same behavioral and normative beliefs...

  10. Climate predictors of late quaternary extinctions

    DEFF Research Database (Denmark)

    Nogués-Bravo, David; Ohlemüller, Ralf; Batra, Persaram

    2010-01-01

    Between 50,000 and 3,000 years before present (BP) 65% of mammal genera weighing over 44 kg went extinct, together with a lower proportion of small mammals. Why species went extinct in such large numbers is hotly debated. One of the arguments proposes that climate changes underlie Late Quaternary...... extinctions, but global quantitative evidence for this hypothesis is still lacking. We test the potential role of global climate change on the extinction of mammals during the Late Quaternary. Our results suggest that continents with the highest climate footprint values, in other words, with climate changes...... of greater magnitudes during the Late Quaternary, witnessed more extinctions than continents with lower climate footprint values, with the exception of South America. Our results are consistent across species with different body masses, reinforcing the view that past climate changes contributed to global...

  11. Late effects of thoracic irradiation in children

    Energy Technology Data Exchange (ETDEWEB)

    Boelling, T.; Koenemann, S.; Ernst, I.; Willich, N. [Dept. of Radiotherapy, Univ. Hospital of Muenster (Germany)

    2008-06-15

    Purpose: to summarize the literature regarding the late effects of radiotherapy to the thorax in childhood and adolescence with special emphasis on cardiac and pulmonary impairment. Material und methods: the literature was critically reviewed using the PubMed {sup registered} database with the key words 'late effects', 'late sequelae', 'child', 'childhood', 'adolescence', 'radiation', 'radiotherapy', 'thorax', 'lung', 'heart', and 'pulmonary'. Results: 17 publications dealing with radiation-induced pulmonary and cardiac late sequelae in children could be identified and were analyzed in detail. 29 further publications with additional information were also included in the analysis. Pulmonary function impairment after mediastinal irradiation arose in one third of all pediatric patients, even when treatment was performed with normofractionated lower doses (15-25 Gy). Whole lung irradiation was regularly followed by pulmonary function impairment with differing rates in several reports. However, clinically symptomatic function impairment like dyspnea was less frequent. Irradiation of up to 25 Gy (single doses {<=} 2 Gy) to the heart showed little or no cardiac toxicity in analyses of irradiated children (median follow-up 1.3-14.3 years). Doses of > 25 Gy (single doses {<=} 2-3.3 Gy) led to several cardiac dysfunctions. However, new data from adults with longer follow-up may indicate threshold doses as low as 1 Gy. Impairment of skeletal growth, breast hypoplasia, and secondary malignancy were further potential late sequelae. Conclusion: several retrospective reports described radiation-associated late sequelae in children. However, there is still a lack of sufficient data regarding the characterization of dose-volume effects. (orig.)

  12. Late Cretaceous vicariance in Gondwanan amphibians.

    Directory of Open Access Journals (Sweden)

    Ines Van Bocxlaer

    Full Text Available Overseas dispersals are often invoked when Southern Hemisphere terrestrial and freshwater organism phylogenies do not fit the sequence or timing of Gondwana fragmentation. We used dispersal-vicariance analyses and molecular timetrees to show that two species-rich frog groups, Microhylidae and Natatanura, display congruent patterns of spatial and temporal diversification among Gondwanan plates in the Late Cretaceous, long after the presumed major tectonic break-up events. Because amphibians are notoriously salt-intolerant, these analogies are best explained by simultaneous vicariance, rather than by oceanic dispersal. Hence our results imply Late Cretaceous connections between most adjacent Gondwanan landmasses, an essential concept for biogeographic and palaeomap reconstructions.

  13. A case of late-onset oligomeganephronia

    Directory of Open Access Journals (Sweden)

    Rafael José Vargas Alves

    2012-12-01

    Full Text Available A 33-year old caucasian man was investigated for pain in the right flank, proteinuria, hemathuria and an elevated serum creatinine level. He also presented an abnormal ultrasonography, which revealed asymmetric kidneys. Through renal biopsy, the diagnosis of oligomeganephronia (OMN was confirmed. OMN is a very rare form of renal hypoplasia, and late-onset in adulthood is even rarer. In the pediatric population, OMN leads to end-stage-renal-failure(ESRF in a few years. This is the sixth case related in the literature of a late-onset OMN who have not yet developed ESRF.

  14. Late complication after radiotherapy for testicular tumor

    Energy Technology Data Exchange (ETDEWEB)

    Mineyama, Hirotada; Komatsubara, Shuichi; Sakata, Yasunosuke; Abe, Norio (Niigata Prefectural Cancer Center (Japan). Niigata Hospital)

    1983-12-01

    During the past 21 years, 105 patients with germinal testicular tumor were treated in our hospital; 86 out of 105 patients were irradiated postoperatively. Late radiation injury was observed in 14 patients: Cutaneosigmoidal fistula in 1 patient, ileus (jejunum necrosis) in 1 patient, gastric ulcer in 1 patient, duodenal ulcer and stenosis in 1 patient, lung fibrosis in 1 patient, radiation cystitis in 1 patient, severe lymph edema of lower extremity in 1 patient, muscle atrophy of lower extremity in 1 patient, lower extremity growth disturbances in 3 children and severe abdominal cutancosubcutaneal fibrosis in 3 patient. Two cases of late radiation injury are presented and discussed.

  15. Method of controlling power of a heavy water reactor

    International Nuclear Information System (INIS)

    Masuda, Hiroyuki.

    1975-01-01

    Object: To adjust a level of heavy water in a region of reflection body to control power in a heavy water reactor. Structure: The interior of a core tank filled with heavy water is divided by a partition into a core heavy water region and a reflection body region formed by surrounding the core heavy water region, and a level of heavy water within the reflection body region is adjusted to control power. Preferably, it is desirable to communicate the core heavy water region with the reflection body heavy water region at their lower portion, and gas pressure applied to an upper portion within at least one of said regions is adjusted to adjust the level of heavy water within the reflection body heavy water region. Thereby, the heavy water within the reflection body heavy water region may be introduced into the core region, thus requiring no tank which stores heavy water within the reflection body region. (Kamimura, M.)

  16. International Conference on Heavy Vehicles HVParis 2008 : Heavy Vehicle Transport Technology (HVTT 10)

    OpenAIRE

    JACOB, Bernard; NORDENGEN, Paul; O'CONNOR, Alan; BOUTELDJA, Mohamed

    2008-01-01

    Sommaire : Heavy vehicles and WIM technology, testing and standards. Interactions between heavy vehicles or trains and the infrastructure, environment and other system users. Heavy vehicle and road management information: measurements, data quality, data management. Freight mobility and safety. Vehicle classification, size and weight evaluation, regulations and enforcement. Traffic and road safety. WIM of road vehicles, trains and aeroplanes.

  17. Status and prospects for lattice calculations in heavy quark physics

    International Nuclear Information System (INIS)

    Wittig, H.; Forschungszentrum Juelich GmbH

    1996-06-01

    The current status of lattice calculation of weak matrix elements for heavy quark systems is reviewed. After an assessment of systematic errors in present simulations, results for the B meson decay constant, the B parameter B B and semi-leptonic heavy-to-light and heavy-to-heavy transitions are discussed. The final topic are lattice results for heavy baryon spectroscopy. (orig.)

  18. Hypothyroidism in late-onset Pompe disease

    Directory of Open Access Journals (Sweden)

    Joseph Schneider

    2016-09-01

    Conclusions: Hypothyroidism was found at a higher prevalence in patients with late-onset Pompe disease compared to the general adult population at UMMC. Studies in larger populations of patients with Pompe disease would be needed to confirm an association of Pompe disease and hypothyroidism. Challenges include finding an adequate sample size, due the rarity of Pompe disease.

  19. Progression of Late-Onset Stargardt Disease

    NARCIS (Netherlands)

    Lambertus, S.; Lindner, M.; Bax, N.M.; Mauschitz, M.M.; Nadal, J.; Schmid, M.; Schmitz-Valckenberg, S.; Hollander, A.I. den; Weber, B.H.; Holz, F.G.; Wilt, G.J. van der; Fleckenstein, M.; Hoyng, C.B.

    2016-01-01

    Purpose: Identification of sensitive biomarkers is essential to determine potential effects of emerging therapeutic trials for Stargardt disease. This study aimed to describe the natural history of late-onset Stargardt, and demonstrates the accuracy of retinal pigment epithelium (RPE) atrophy

  20. Late effects of radiation: host factors

    International Nuclear Information System (INIS)

    Fry, R.J.M.; Storer, J.B.

    1983-01-01

    The paper discusses the influence of host factors on radiation late effects and in particular cancer. Radiation induces cellular changes that result in initiated cells with a potential to become cancers. The expression of the initiated cells as tumors is influenced, if not determined, by both tissue and systemic factors that are sex-, age-, and species-dependent

  1. 30 CFR 870.21 - Late payments.

    Science.gov (United States)

    2010-07-01

    ... Government. The Treasury current value of funds rate is published annually in the Federal Register and on... fees and interest. (c) When a reclamation fee debt is more than 91 days overdue, a 6 percent annual... fee was owed are subject to interest. Late reclamation fee payments are subject to interest at the...

  2. Late time phase transition as dark energy

    Indian Academy of Sciences (India)

    Abstract. We show that the dark energy field can naturally be described by the scalar condensates of a non-abelian gauge group. This gauge group is unified with the standard model gauge groups and it has a late time phase transition. The small phase transition explains why the positive acceleration of the universe is ...

  3. Late Miocene magnetostratigraphy in the Mediterranean

    NARCIS (Netherlands)

    Langereis, C.G.

    1984-01-01

    Reversals of the geomagnetic field In the geological past are recorded globally in the natural remanent magnetization (NRM) of igneous and sedimentary rock sequences. The accurate and rei iable reconstruction of this record is the basis of magnetostratigraphy. The magnetostratigraphy of Late

  4. Late Miocene magnetostratigraphy in the Mediterranean

    NARCIS (Netherlands)

    Langereis, C.G.

    1984-01-01

    Reversals of the geomagnetic field In the geological past are recorded globally in the natural remanent magnetization (NRM) of igneous and sedimentary rock sequences. The accurate and rei iable reconstruction of this record is the basis of magnetostratigraphy. The magnetostratigraphy of Late Miocene

  5. Language Control Abilities of Late Bilinguals

    Science.gov (United States)

    Festman, Julia

    2012-01-01

    Although all bilinguals encounter cross-language interference (CLI), some bilinguals are more susceptible to interference than others. Here, we report on language performance of late bilinguals (Russian/German) on two bilingual tasks (interview, verbal fluency), their language use and switching habits. The only between-group difference was CLI:…

  6. Causes for Late onset Alcohol Use Disorder

    DEFF Research Database (Denmark)

    Emiliussen, Jakob; Nielsen, Anette Søgaard; Andersen, Kjeld

    the studies. The results of this review are generally inconclusive. In spite of the low quality scores, we did find that chronic stress, role/identity loss and friends approval of drinking, was associated with an increased risk for late-onset AUD whereas retirement, death of spouse or close relative does...

  7. Nuclear research with heavy ions

    International Nuclear Information System (INIS)

    Kaplan, M.

    1991-08-01

    This report discusses the following topics: Asymmetric fission of 149 Tb* from the finite-range, rotating-liquid-drop model: mean total kinetic energies for binary fragmentation; charged-particle evaporation from hot composite nuclei: evidence over a broad Z range for distortions from cold nuclear profiles; the role of reversed kinematics and double kinematic solutions in nuclear reactions studies; production of intermediate-mass-fragments in the reaction 98 Mo + 51 V at an excitation energy E* = 224-MeV; emission of light charged particles in the reaction 344-MeV 28 Si + 121 Sb; continued developments of the statistical evaporation code LILITA N90; and planning for heavy-ion-collision studies at very high energies: the STAR collaboration at RHIC

  8. QCD in heavy ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Iancu, Edmond [IPhT, Saclay (France)

    2014-07-01

    These lectures provide a modern introduction to selected topics in the physics of ultrarelativistic heavy ion collisions which shed light on the fundamental theory of strong interactions, the Quantum Chromodynamics. The emphasis is on the partonic forms of QCD matter which exist in the early and intermediate stages of a collision -- the colour glass condensate, the glasma, and the quark-gluon plasma -- and on the effective theories that are used for their description. These theories provide qualitative and even quantitative insight into a wealth of remarkable phenomena observed in nucleus-nucleus or deuteron-nucleus collisions at RHIC and/or the LHC, like the suppression of particle production and of azimuthal correlations at forward rapidities, the energy and centrality dependence of the multiplicities, the ridge effect, the limiting fragmentation, the jet quenching, or the dijet asymmetry.

  9. QCD in heavy ion collisions

    International Nuclear Information System (INIS)

    Iancu, Edmond

    2014-01-01

    These lectures provide a modern introduction to selected topics in the physics of ultrarelativistic heavy ion collisions which shed light on the fundamental theory of strong interactions, the Quantum Chromodynamics. The emphasis is on the partonic forms of QCD matter which exist in the early and intermediate stages of a collision -- the colour glass condensate, the glasma, and the quark-gluon plasma -- and on the effective theories that are used for their description. These theories provide qualitative and even quantitative insight into a wealth of remarkable phenomena observed in nucleus-nucleus or deuteron-nucleus collisions at RHIC and/or the LHC, like the suppression of particle production and of azimuthal correlations at forward rapidities, the energy and centrality dependence of the multiplicities, the ridge effect, the limiting fragmentation, the jet quenching, or the dijet asymmetry

  10. Jets in heavy ion collisions

    International Nuclear Information System (INIS)

    Nattrass, Christine

    2017-01-01

    High energy collisions of heavy nuclei permit the study of nuclear matter at temperatures and energy densities so high that the fundamental theory for strong interactions, QCD, predicts a phase transition to a plasma of quarks and gluons. This matter, called a Quark Gluon Plasma (QGP), has been studied experimentally for the last decade and has been observed to be a strongly interacting liquid with a low viscosity. High energy partons created early in the collision interact with the QGP and provide unique probes of its properties. Hard partons fragment into collimated sprays of particles called jets and have been studied through measurements of single particles, correlations between particles, and measurements of fully reconstructed jets. These measurements demonstrate partonic energy loss in the QGP and constrain the QGP’s properties. Measurements of the jet structure give insight into the mechanism of this energy loss. The information we have learned from studies of jets and challenges for the field will be reviewed. (paper)

  11. Heavy Higgs searches. Flavour matters

    International Nuclear Information System (INIS)

    Gori, Stefania; Paul, Ayan

    2017-10-01

    We point out that the stringent lower bounds on the masses of additional electrically neutral and charged Higgs bosons crucially depend on the flavour structure of their Yukawa interactions. We show that these bounds can easily be evaded by the introduction of flavour-changing neutral currents in the Higgs sector. As an illustration, we study the phenomenology of a two Higgs doublet model with a Yukawa texture singling out the third family of quarks and leptons. We combine constraints from low-energy flavour physics measurements, LHC measurements of the 125 GeV Higgs boson rates, and LHC searches for new heavy Higgs bosons. We propose novel LHC searches that could be performed in the coming years to unravel the existence of these new Higgs bosons.

  12. Heavy quark physics from SLD

    Energy Technology Data Exchange (ETDEWEB)

    Messner, R. [Stanford Univ., CA (United States)

    1997-01-01

    This report covers preliminary measurements from SLD on heavy quark production at the Z{sup 0}, using 150,000 hadronic Z{sup 0} decays accumulated during the 1993-1995 runs. A measurement of R{sub b} with a lifetime double tag is presented. The high electron beam polarization of the SLC is employed in the direct measurement of the parity-violating parameters A{sub b} and A{sub c} by use of the left-right forward-backward asymmetry. The lifetimes of B{sup +} and B{sup 0} mesons have been measured by two analyses. The first identifies semileptonic decays of B mesons with high (p,p{sub t}) leptons; the second analysis isolates a sample of B meson decays with a two-dimensional impact parameter tag and reconstructs the decay length and charge using a topological vertex reconstruction method.

  13. Heavy quark physics from SLD

    International Nuclear Information System (INIS)

    Messner, R.

    1997-01-01

    This report covers preliminary measurements from SLD on heavy quark production at the Z 0 , using 150,000 hadronic Z 0 decays accumulated during the 1993-1995 runs. A measurement of R b with a lifetime double tag is presented. The high electron beam polarization of the SLC is employed in the direct measurement of the parity-violating parameters A b and A c by use of the left-right forward-backward asymmetry. The lifetimes of B + and B 0 mesons have been measured by two analyses. The first identifies semileptonic decays of B mesons with high (p,p t ) leptons; the second analysis isolates a sample of B meson decays with a two-dimensional impact parameter tag and reconstructs the decay length and charge using a topological vertex reconstruction method

  14. Heavy Higgs searches. Flavour matters

    Energy Technology Data Exchange (ETDEWEB)

    Gori, Stefania [Cincinnati Univ., OH (United States). Dept. of Physics; Grojean, Christophe [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Humboldt-Universitaet, Berlin (Germany). Inst. fuer Physik; Juste, Aurelio [Institut de Fisica d' Altes Energies (IFAE), Barcelona (Spain); Institucio Catalanade Recerca i Estudis Avancats (ICREA), Barcelona (Spain); Paul, Ayan [INFN, Sezione di Roma (Italy)

    2017-10-15

    We point out that the stringent lower bounds on the masses of additional electrically neutral and charged Higgs bosons crucially depend on the flavour structure of their Yukawa interactions. We show that these bounds can easily be evaded by the introduction of flavour-changing neutral currents in the Higgs sector. As an illustration, we study the phenomenology of a two Higgs doublet model with a Yukawa texture singling out the third family of quarks and leptons. We combine constraints from low-energy flavour physics measurements, LHC measurements of the 125 GeV Higgs boson rates, and LHC searches for new heavy Higgs bosons. We propose novel LHC searches that could be performed in the coming years to unravel the existence of these new Higgs bosons.

  15. Heavy quark hadron mass scale

    International Nuclear Information System (INIS)

    Anderson, J.T.

    1994-01-01

    Without the spin interactions the hardron masses within a multiplet are degenerate. The light quark hadron degenerate mulitplet mass spectrum is extended from the 3 quark ground state multiplets at J P =0 - , 1/2 + , 1 - to include the excited states which follow the spinorial decomposition of SU(2)xSU(2). The mass scales for the 4, 5, 6, .. quark hadrons are obtained from the degenerate multiplet mass m 0 /M=n 2 /α with n=4, 5, 6, .. The 4, 5, 6, .. quark hadron degenerate multiplet masses follow by splitting of the heavy quark mass scales according to the spinorial decomposition of SU(2)xSU(2). (orig.)

  16. Heavy Duty Vehicle Futures Analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Askin, Amanda Christine; Barter, Garrett.; West, Todd H.; Manley, Dawn Kataoka

    2014-05-01

    This report describes work performed for an Early Career Research and Development project. This project developed a heavy-duty vehicle (HDV) sector model to assess the factors influencing alternative fuel and efficiency technology adoption. This model builds on a Sandia light duty vehicle sector model and provides a platform for assessing potential impacts of technological advancements developed at the Combustion Research Facility. Alternative fuel and technology adoption modeling is typically developed around a small set of scenarios. This HDV sector model segments the HDV sector and parameterizes input values, such as fuel prices, efficiencies, and vehicle costs. This parameterization enables sensitivity and trade space analyses to identify the inputs that are most associated with outputs of interest, such as diesel consumption and greenhouse gas emissions. Thus this analysis tool enables identification of the most significant HDV sector drivers that can be used to support energy security and climate change goals.

  17. Heavy ion physics at CERN

    International Nuclear Information System (INIS)

    Vesztergombi, G.

    1991-01-01

    A summary of the present status and future plans for heavy ion experiments at CERN-SPS and CERN-LHC accelerators is given. The planned three phases give possibilities to study the properties of the quark-gluon-plasma (QGP). At the present stage the feasibility of high energy ion-ion experiments with their very abundant secondary hadron production, shows that there is a chance to obtain high densities, and to look for the onset of new, collective phenomena. In a second phase, there should be a chance to obtain more conclusive evidence for the onset of quark deconfinement. In the third stage, the average energy densities rise above the deconfinement threshold, so that a study of the properties of QGP should become possible. (G.P.)

  18. Progress in Heavy Ion Fusion

    International Nuclear Information System (INIS)

    Herrmannsfeldt, W.B.

    1988-09-01

    The progress of the field of Heavy Ion Fusion has been documented in the proceedings of the series of International Symposia that, in recent years, have occurred every second year. The latest of these conferences was hosted by Gesellshaft fuer Schwerionenforshung (GSI) in Darmstadt, West Germany, June 28-30, 1988. For this report, a few highlights from the conference are selected, stressing experimental progress and prospects for future advances. A little extra time is devoted to report on the developments at the Lawrence Berkeley Laboratory (LBL) which is the center for most of the HIFAR program. The Director of the HIFAR program at LBL is Denis Keefe, who presented the HIF report at the last two of the meetings in this series, and in whose place the author is appearing now. 4 refs., 1 fig

  19. Process to hydroform heavy petroleum

    Energy Technology Data Exchange (ETDEWEB)

    Sinfelt, J.H.; Barnett, A.E.

    1977-02-17

    The invention concerns the hydroforming of heavy petrol. A particularly high degree of conversion of paraffins into aromatic substances is achieved. This leads to a a considerable increase of the octane number above 100. The hydroforming takes place by contacting the initial product with a catalyst in the presence of hydrogen. The temperature here is 427/sup 0/ to 566/sup 0/C. A mixture of 0.05-2 wt.% iridium, 0.5-2 wt.% gold, silver and copper serves as catalyst. It is coated on an oxidic carrier with a large surface, e.g. aluminium oxide with a surface of 50-300 m/sup 2//g. The larger the surface, the greater the reaction rate. The iridium acts as active catalyst, gold reduces the cracking activity of the catalyst and improves the product yield in the boiling range of benzine.

  20. Heavy Vehicle Technologies Program Retrospective and Outlook

    International Nuclear Information System (INIS)

    James J. Eberhardt

    1999-01-01

    OHVT Mission is to conduct, in collaboration with our heavy vehicle industry partners and their suppliers, a customer-focused national program to research and develop technologies that will enable trucks and other heavy vehicles to be more energy efficient and able to use alternative fuels while simultaneously reducing emissions