WorldWideScience

Sample records for earth matter effects

  1. Neutrino mass hierarchy and matter effects

    OpenAIRE

    Smirnov, Alexei Yu.

    2013-01-01

    Matter effects modify the mixing and the effective masses of neutrinos in a way which depends on the neutrino mass hierarchy. Consequently, for normal and inverted hierarchies the oscillations and flavor conversion results are different. Sensitivity to the mass hierarchy appears whenever the matter effects on the 1-3 mixing and mass splitting become substantial. This happens in supernovae in wide energy range and in the matter of the Earth. The Earth density profile is a multi-layer medium wh...

  2. Signatures of Earth-scattering in the direct detection of Dark Matter

    DEFF Research Database (Denmark)

    Kavanagh, Bradley J.; Catena, Riccardo; Kouvaris, Chris

    2017-01-01

    Direct detection experiments search for the interactions of Dark Matter (DM) particles with nuclei in terrestrial detectors. But if these interactions are sufficiently strong, DM particles may scatter in the Earth, affecting their distribution in the lab. We present a new analytic calculation...... of this 'Earth-scattering' effect in the regime where DM particles scatter at most once before reaching the detector. We perform the calculation self-consistently, taking into account not only those particles which are scattered away from the detector, but also those particles which are deflected towards...... the detector. Taking into account a realistic model of the Earth and allowing for a range of DM-nucleon interactions, we present the EarthShadow code, which we make publicly available, for calculating the DM velocity distribution after Earth-scattering. Focusing on low-mass DM, we find that Earth...

  3. Direct detection of dark matter bound to the Earth

    DEFF Research Database (Denmark)

    Catena, Riccardo; Kouvaris, Chris

    2017-01-01

    We study the properties and direct detection prospects of an as of yet neglected population of dark matter (DM) particles moving in orbits gravitationally bound to the Earth. This DM population is expected to form via scattering by nuclei in the Earth's interior. We compute fluxes and nuclear...

  4. In situ determination of Earth matter density in a neutrino factory

    Science.gov (United States)

    Minakata, Hisakazu; Uchinami, Shoichi

    2007-04-01

    We point out that an accurate in situ determination of the earth matter density ρ is possible in neutrino factory by placing a detector at the magic baseline, L=2π/GFNe where Ne denotes electron number density. The accuracy of matter density determination is excellent in a region of relatively large θ13 with fractional uncertainty δρ/ρ of about 0.43%, 1.3%, and ≲3% at 1σ CL at sin⁡22θ13=0.1, 10-2, and 3×10-3, respectively. At smaller θ13 the uncertainty depends upon the CP phase δ, but it remains small, 3% 7% in more than 3/4 of the entire region of δ at sin⁡22θ13=10-4. The results would allow us to solve the problem of obscured CP violation due to the uncertainty of earth matter density in a wide range of θ13 and δ. It may provide a test for the geophysical model of the earth, or it may serve as a method for a stringent test of the Mikheyev-Smirnov-Wolfenstein theory of neutrino propagation in matter once an accurate geophysical estimation of the matter density is available.

  5. Cosmic acceleration of Earth and the Moon by dark matter

    Science.gov (United States)

    Nordtvedt, Kenneth L.

    1994-01-01

    In order to test the hypothesis that the gravitational interaction between our Galaxy's dark matter and the ordinary matter in Earth and the Moon might not fulfill the equivalence principle (universality of free fall), we consider the pertinent perturbation of the lunar orbit -- a sidereal month period range oscillation resulting from a spatially fixed polarization of the orbit. Lunar laser ranging (LLR) data can measure this sidereal perturbation to an accuracy equal to or better than its existing measurement of the synodic month period range oscillation amplitude (+/- 3 cm) which has been used for testing whether Earth and the Moon accelerate at equal rates toward the Sun. Because of the slow precession rate of the Moon's perigree (8.9 yr period), the lunar orbit is particularly sensitive to a cosmic acceleration; the LLR fit of the orbit places an upper limit of 10(exp -13) cm/sq. s for any cosmic differential acceleration between Earth (Fe) and the Moon (silicates). This is 10(exp -5) of the total galactic acceleration of the solar system, of which, it has been suggested, a large portion is produced by dark matter.

  6. Dark photons from the center of the Earth: Smoking-gun signals of dark matter

    Science.gov (United States)

    Feng, Jonathan L.; Smolinsky, Jordan; Tanedo, Philip

    2016-01-01

    Dark matter may be charged under dark electromagnetism with a dark photon that kinetically mixes with the Standard Model photon. In this framework, dark matter will collect at the center of the Earth and annihilate into dark photons, which may reach the surface of the Earth and decay into observable particles. We determine the resulting signal rates, including Sommerfeld enhancements, which play an important role in bringing the Earth's dark matter population to their maximal, equilibrium value. For dark matter masses mX˜100 GeV - 10 TeV , dark photon masses mA'˜MeV -GeV , and kinetic mixing parameters ɛ ˜1 0-9- 1 0-7 , the resulting electrons, muons, photons, and hadrons that point back to the center of the Earth are a smoking-gun signal of dark matter that may be detected by a variety of experiments, including neutrino telescopes, such as IceCube, and space-based cosmic ray detectors, such as Fermi-LAT and AMS. We determine the signal rates and characteristics and show that large and striking signals—such as parallel muon tracks—are possible in regions of the (mA',ɛ ) plane that are not probed by direct detection, accelerator experiments, or astrophysical observations.

  7. Effects of resonant matter oscillation in earth on solar neutrino detection

    International Nuclear Information System (INIS)

    Hiroi, Shinichi; Sakuma, Hiroko; Yanagida, Tsutomu; Yoshimura, Motohiko.

    1987-01-01

    A systematic study of the Mikheyev-Smirnov-Wolfenstein (MSW) effect in earth is carried out on the solar neutrino flux from 8 B decay. In Kamiokande type detectors day-night difference of rates, seasonal variation and recoil electron spectrum are found to be good indicators of the earth effect for a range of mixing parameters around δm 2 = 3 x 10 -6 ev 2 and sin 2 2θ = 0.2. (author)

  8. Earth matter effects at very long baselines and the neutrino mass hierarchy

    International Nuclear Information System (INIS)

    Gandhi, Raj; Ghoshal, Pomita; Goswami, Srubabati; Mehta, Poonam; Sankar, S. Uma

    2006-01-01

    We study matter effects which arise in the muon neutrino oscillation and survival probabilities relevant to atmospheric neutrino and very long baseline (>4000 Km) beam experiments. The interrelations between the three probabilities P μe , P μτ , and P μμ are examined. It is shown that large and observable sensitivity to the neutrino mass hierarchy can be present in P μμ and P μτ . We emphasize that at baselines >7000 Km, matter effects in P μτ are important under certain conditions and can be large. The muon survival rates in experiments with very long baselines thus depend on matter effects in both P μτ and P μe . We also indicate where these effects provide sensitivity to θ 13 and identify ranges of energies and baselines where this sensitivity is maximum. The effect of parameter degeneracies in the three probabilities at these baselines and energies is studied in detail and large parts of the parameter space are identified which are free from these degeneracies. In the second part of the paper, we focus on using the matter effects studied in the first part as a means of determining the mass hierarchy via atmospheric neutrinos. Realistic event rate calculations are performed for a charge discriminating 100 kT iron calorimeter which demonstrate the possibility of realizing this very important goal in neutrino physics. It is shown that for atmospheric neutrinos, a careful selection of energy and baseline ranges is necessary in order to obtain a statistically significant signal, and that the effects are largest in bins where matter effects in both P μe and P μτ combine constructively. Under these conditions, up to a 4σ signal for matter effects is possible (for Δ 31 >0) within a time scale appreciably shorter than the one anticipated for neutrino factories

  9. Matter Density Profile Shape Effects at DUNE

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Kevin J. [Northwestern U.; Parke, Stephen J. [Fermilab

    2018-02-19

    Quantum mechanical interactions between neutrinos and matter along the path of propagation, the Wolfenstein matter effect, are of particular importance for the upcoming long-baseline neutrino oscillation experiments, specifically the Deep Underground Neutrino Experiment (DUNE). Here, we explore specifically what about the matter density profile can be measured by DUNE, considering both the shape and normalization of the profile between the neutrinos' origin and detection. Additionally, we explore the capability of a perturbative method for calculating neutrino oscillation probabilities and whether this method is suitable for DUNE. We also briefly quantitatively explore the ability of DUNE to measure the Earth's matter density, and the impact of performing this measurement on measuring standard neutrino oscillation parameters.

  10. Investigating Earth shadowing effect with DAMA/LIBRA-phase1

    Energy Technology Data Exchange (ETDEWEB)

    Bernabei, R.; Belli, P.; D' Angelo, S.; Di Marco, A. [Universita di Roma ' ' Tor Vergata' ' , Dipt. di Fisica, Rome (Italy); INFN, sez. Roma ' ' Tor Vergata' ' , Rome (Italy); Montecchia, F. [Universita di Roma ' ' Tor Vergata' ' , Dipt. di Fisica, Rome (Italy); INFN, sez. Roma ' ' Tor Vergata' ' , Rome (Italy); Universita di Roma ' ' Tor Vergata' ' , Dipt. di Ingegneria Civile e Ingegneria Informatica, Rome (Italy); D' Angelo, A.; Incicchitti, A. [Universita di Roma ' ' La Sapienza' ' , Dipt. di Fisica, Rome (Italy); INFN, sez. Roma, Rome (Italy); Cappella, F.; Caracciolo, V.; Cerulli, R. [INFN, Laboratori Nazionali del Gran Sasso, Assergi (Italy); Dai, C.J.; He, H.L.; Kuang, H.H.; Ma, X.H.; Sheng, X.D.; Wang, R.G. [Chinese Academy of Sciences, Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Beijing (China); Ye, Z.P. [Chinese Academy of Sciences, Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Beijing (China); University of Jing Gangshan, Ji' an, Jiangxi (China)

    2015-05-15

    In the present paper the results obtained in the investigation of possible diurnal effects for low-energy single-hit scintillation events of DAMA/LIBRA-phase1 (1.04 ton x year exposure) have been analysed in terms of an effect expected in case of dark matter (DM) candidates inducing nuclear recoils and having high cross-section with ordinary matter, which implies low DM local density in order to fulfill the DAMA/LIBRA DM annual modulation results. This effect is due to the different Earth depths crossed by those DM candidates during the sidereal day. (orig.)

  11. Can the flyby anomaly be attributed to earth-bound dark matter?

    International Nuclear Information System (INIS)

    Adler, Stephen L.

    2009-01-01

    We make preliminary estimates to assess whether the recently reported flyby anomaly can be attributed to dark matter interactions. We consider both elastic and exothermic inelastic scattering from dark matter constituents; for isotropic dark matter velocity distributions, the former decrease, while the latter increase, the final flyby velocity. The fact that the observed flyby velocity anomaly shows examples with both positive and negative signs, requires the dominance of different dark matter scattering processes along different flyby trajectories. The magnitude of the observed anomalies requires dark matter densities many orders of magnitude greater than the galactic halo density. Such a large density could result from an accumulation cascade, in which the solar system-bound dark matter density is much higher than the galactic halo density, and the earth-bound density is much higher than the solar system-bound density. We discuss a number of strong constraints on the hypothesis of a dark matter explanation for the flyby anomaly. These require dark matter to be non-self-annihilating, with the dark matter scattering cross section on nucleons much larger, and the dark matter mass much lighter, than usually assumed.

  12. Signatures of Earth-scattering in the direct detection of Dark Matter

    DEFF Research Database (Denmark)

    Kavanagh, Bradley J.; Catena, Riccardo; Kouvaris, Chris

    2017-01-01

    Direct detection experiments search for the interactions of Dark Matter (DM) particles with nuclei in terrestrial detectors. But if these interactions are sufficiently strong, DM particles may scatter in the Earth, affecting their distribution in the lab. We present a new analytic calculation...

  13. Prospectors and Developers Association of Canada Mining Matters: A Model of Effective Outreach

    Science.gov (United States)

    Hymers, L.; Heenan, S.

    2009-05-01

    , effectiveness and suitability of Mining Matters resources and training workshops for classroom instruction. Mining Matters also operates an Aboriginal Youth Outreach Program that promotes the importance of the minerals industry to Aboriginal youth through the distribution of educational resources, the provision of educational opportunities, and exposure to mineral and mining industry career opportunities and professionals. The Aboriginal Youth Outreach Program is designed to engage youth in Earth Sciences, providing them with the opportunity to develop skills, competencies and knowledge through Earth science, career, and skills development education. The Mining Matters program is effective and has garnered a National reputation for excellence. The Mining Matters program is a model of effective partnerships between industry, academia, and education outreach organizations. Our resources are currently used in Ontario, Manitoba, Saskatchewan, and British Columbia, with new partnerships being developed in Quebec and Nova Scotia.

  14. Dark matter comes into sharper focus - on Earth and in the heavens

    CERN Multimedia

    1990-01-01

    Observation of an elliptical galaxy that is acting as a gravitational lens, is helping astronomers in their understanding of dark matter. At the same time, experiments on earth have ruled out some of the hypothetical candidates for its composition (1

  15. The earth's gravitational field

    Digital Repository Service at National Institute of Oceanography (India)

    Ramprasad, T.

    . But to say that gravity acts downwards is not correct. Gravity acts down, no matter where you stand on the Earth. It is better to say that on Earth gravity pulls objects towards the centre of the Earth. So no matter where you are on Earth all objects fall... pull than objects at the poles. In combination, the equatorial bulge and the effects of centrifugal force mean that sea-level gravitational acceleration increases from about 9.780 m/s² at the equator to about 9.832 m/s² at the poles, so an object...

  16. Terrestrial effects on dark matter-electron scattering experiments

    DEFF Research Database (Denmark)

    Emken, Timon; Kouvaris, Chris; Shoemaker, Ian M.

    2017-01-01

    A well-studied possibility is that dark matter may reside in a sector secluded from the Standard Model, except for the so-called photon portal: kinetic mixing between the ordinary and dark photons. Such interactions can be probed in dark matter direct detection experiments, and new experimental...... techniques involving detection of dark matter-electron scattering offer new sensitivity to sub-GeV dark matter. Typically however it is implicitly assumed that the dark matter is not altered as it traverses the Earth to arrive at the detector. In this paper we study in detail the effects of terrestrial...... stopping on dark photon models of dark matter, and find that they significantly reduce the sensitivity of XENON10 and DAMIC. In particular we find that XENON10 only excludes masses in the range (5-3000) MeV while DAMIC only probes (20-50) MeV. Their corresponding cross section sensitivity is reduced...

  17. First search for dark matter annihilations in the Earth with the IceCube detector

    International Nuclear Information System (INIS)

    Aartsen, M.G.; Hill, G.C.; Robertson, S.; Wallace, A.; Whelan, B.J.; Abraham, K.; Bernhard, A.; Coenders, S.; Holzapfel, K.; Huber, M.; Jurkovic, M.; Krings, K.; Resconi, E.; Turcati, A.; Veenkamp, J.; Ackermann, M.; Bernardini, E.; Blot, S.; Bretz, H.P.; Franckowiak, A.; Gluesenkamp, T.; Jacobi, E.; Karg, T.; Kintscher, T.; Kunwar, S.; Mohrmann, L.; Nahnhauer, R.; Satalecka, K.; Spiering, C.; Stasik, A.; Stoessl, A.; Strotjohann, N.L.; Terliuk, A.; Usner, M.; Santen, J. van; Yanez, J.P.; Adams, J.; Aguilar, J.A.; Ansseau, I.; Heereman, D.; Meagher, K.; Meures, T.; O'Murchadha, A.; Pinat, E.; Raab, C.; Ahlers, M.; Braun, J.; Chirkin, D.; Day, M.; Desiati, P.; Diaz-Velez, J.C.; Fahey, S.; Feintzeig, J.; Ghorbani, K.; Gladstone, L.; Griffith, Z.; Halzen, F.; Hanson, K.; Jero, K.; Karle, A.; Kauer, M.; Kelley, J.L.; Kheirandish, A.; Krueger, C.; Mancina, S.; McNally, F.; Merino, G.; Sabbatini, L.; Tobin, M.N.; Tosi, D.; Vandenbroucke, J.; Rossem, M. van; Wandkowsky, N.; Wendt, C.; Westerhoff, S.; Wille, L.; Xu, D.L.; Ahrens, M.; Bohm, C.; Dumm, J.P.; Finley, C.; Flis, S.; Hultqvist, K.; Walck, C.; Wolf, M.; Zoll, M.; Altmann, D.; Anton, G.; Katz, U.; Kittler, T.; Tselengidou, M.; Andeen, K.; Anderson, T.; Dunkman, M.; Eller, P.; Huang, F.; Keivani, A.; Lanfranchi, J.L.; Pankova, D.V.; Quinnan, M.; Tesic, G.; Weiss, M.J.; Archinger, M.; Baum, V.; Boeser, S.; Pino Rosendo, E. del; Di Lorenzo, V.; Eberhardt, B.; Ehrhardt, T.; Foesig, C.C.; Koepke, L.; Krueckl, G.; Peiffer, P.; Sandroos, J.; Steuer, A.; Wiebe, K.; Argueelles, C.; Axani, S.; Collin, G.H.; Conrad, J.M.; Jones, B.J.P.; Moulai, M.; Auffenberg, J.; Bissok, M.; Glagla, M.; Glauch, T.; Haack, C.; Hansmann, B.; Hansmann, T.; Kemp, J.; Konietz, R.; Leuermann, M.; Leuner, J.; Penek, Oe.; Raedel, L.; Reimann, R.; Rongen, M.; Schimp, M.; Schoenen, S.; Schumacher, L.; Stahlberg, M.; Stettner, J.; Vehring, M.; Vogel, E.; Wallraff, M.; Wickmann, S.; Wiebusch, C.H.; Bai, X.; Barwick, S.W.; Yodh, G.; Bay, R.; Filimonov, K.; Price, P.B.; Woschnagg, K.; Beatty, J.J.; Becker Tjus, J.; Bos, F.; Eichmann, B.; Kroll, M.; Mandelartz, M.; Schoeneberg, S.; Tenholt, F.; Becker, K.H.; Bindig, D.; Helbing, K.; Hickford, S.; Hoffmann, R.; Kopper, S.; Lauber, F.; Naumann, U.; Obertacke Pollmann, A.; Soldin, D.; BenZvi, S.; Cross, R.; Berley, D.; Blaufuss, E.; Cheung, E.; Felde, J.; Friedman, E.; Hellauer, R.; Hoffman, K.D.; Maunu, R.; Olivas, A.; Schmidt, T.; Song, M.; Sullivan, G.W.; Besson, D.Z.; Binder, G.; Gerhardt, L.; Klein, S.R.; Miarecki, S.; Tatar, J.

    2017-01-01

    We present the results of the first IceCube search for dark matter annihilation in the center of the Earth. Weakly interacting massive particles (WIMPs), candidates for dark matter, can scatter off nuclei inside the Earth and fall below its escape velocity. Over time the captured WIMPs will be accumulated and may eventually self-annihilate. Among the annihilation products only neutrinos can escape from the center of the Earth. Large-scale neutrino telescopes, such as the cubic kilometer IceCube Neutrino Observatory located at the South Pole, can be used to search for such neutrino fluxes. Data from 327 days of detector livetime during 2011/2012 were analyzed. No excess beyond the expected background from atmospheric neutrinos was detected. The derived upper limits on the annihilation rate of WIMPs in the Earth and the resulting muon flux are an order of magnitude stronger than the limits of the last analysis performed with data from IceCube's predecessor AMANDA. The limits can be translated in terms of a spin-independent WIMP-nucleon cross section. For a WIMP mass of 50 GeV this analysis results in the most restrictive limits achieved with IceCube data. (orig.)

  18. First search for dark matter annihilations in the Earth with the IceCube detector

    Energy Technology Data Exchange (ETDEWEB)

    Aartsen, M.G.; Hill, G.C.; Robertson, S.; Wallace, A.; Whelan, B.J. [University of Adelaide, Department of Physics, Adelaide (Australia); Abraham, K.; Bernhard, A.; Coenders, S.; Holzapfel, K.; Huber, M.; Jurkovic, M.; Krings, K.; Resconi, E.; Turcati, A.; Veenkamp, J. [Technische Universitaet Muenchen, Physik-Department, Garching (Germany); Ackermann, M.; Bernardini, E.; Blot, S.; Bretz, H.P.; Franckowiak, A.; Gluesenkamp, T.; Jacobi, E.; Karg, T.; Kintscher, T.; Kunwar, S.; Mohrmann, L.; Nahnhauer, R.; Satalecka, K.; Spiering, C.; Stasik, A.; Stoessl, A.; Strotjohann, N.L.; Terliuk, A.; Usner, M.; Santen, J. van; Yanez, J.P. [DESY, Zeuthen (Germany); Adams, J. [University of Canterbury, Department of Physics and Astronomy, Private Bag 4800, Christchurch (New Zealand); Aguilar, J.A.; Ansseau, I.; Heereman, D.; Meagher, K.; Meures, T.; O' Murchadha, A.; Pinat, E.; Raab, C. [Universite Libre de Bruxelles, Science Faculty CP230, Brussels (Belgium); Ahlers, M.; Braun, J.; Chirkin, D.; Day, M.; Desiati, P.; Diaz-Velez, J.C.; Fahey, S.; Feintzeig, J.; Ghorbani, K.; Gladstone, L.; Griffith, Z.; Halzen, F.; Hanson, K.; Jero, K.; Karle, A.; Kauer, M.; Kelley, J.L.; Kheirandish, A.; Krueger, C.; Mancina, S.; McNally, F.; Merino, G.; Sabbatini, L.; Tobin, M.N.; Tosi, D.; Vandenbroucke, J.; Rossem, M. van; Wandkowsky, N.; Wendt, C.; Westerhoff, S.; Wille, L.; Xu, D.L. [University of Wisconsin, Department of Physics and Wisconsin IceCube Particle Astrophysics Center, Madison, WI (United States); Ahrens, M.; Bohm, C.; Dumm, J.P.; Finley, C.; Flis, S.; Hultqvist, K.; Walck, C.; Wolf, M.; Zoll, M. [Stockholm University, Department of Physics, Oskar Klein Centre, Stockholm (Sweden); Altmann, D.; Anton, G.; Katz, U.; Kittler, T.; Tselengidou, M. [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Centre for Astroparticle Physics, Erlangen (Germany); Andeen, K. [Marquette University, Department of Physics, Milwaukee, WI (United States); Anderson, T.; Dunkman, M.; Eller, P.; Huang, F.; Keivani, A.; Lanfranchi, J.L.; Pankova, D.V.; Quinnan, M.; Tesic, G.; Weiss, M.J. [Pennsylvania State University, Department of Physics, University Park, PA (United States); Archinger, M.; Baum, V.; Boeser, S.; Pino Rosendo, E. del; Di Lorenzo, V.; Eberhardt, B.; Ehrhardt, T.; Foesig, C.C.; Koepke, L.; Krueckl, G.; Peiffer, P.; Sandroos, J.; Steuer, A.; Wiebe, K. [University of Mainz, Institute of Physics, Mainz (Germany); Argueelles, C.; Axani, S.; Collin, G.H.; Conrad, J.M.; Jones, B.J.P.; Moulai, M. [Massachusetts Institute of Technology, Department of Physics, Cambridge, MA (United States); Auffenberg, J.; Bissok, M.; Glagla, M.; Glauch, T.; Haack, C.; Hansmann, B.; Hansmann, T.; Kemp, J.; Konietz, R.; Leuermann, M.; Leuner, J.; Penek, Oe.; Raedel, L.; Reimann, R.; Rongen, M.; Schimp, M.; Schoenen, S.; Schumacher, L.; Stahlberg, M.; Stettner, J.; Vehring, M.; Vogel, E.; Wallraff, M.; Wickmann, S.; Wiebusch, C.H. [RWTH Aachen University, III. Physikalisches Institut, Aachen (Germany); Bai, X. [South Dakota School of Mines and Technology, Physics Department, Rapid City, SD (United States); Barwick, S.W.; Yodh, G. [University of California, Department of Physics and Astronomy, Irvine, CA (United States); Bay, R.; Filimonov, K.; Price, P.B.; Woschnagg, K. [University of California, Department of Physics, Berkeley, CA (United States); Beatty, J.J. [Ohio State University, Department of Physics and Center for Cosmology and Astro-Particle Physics, Columbus, OH (United States); Ohio State University, Department of Astronomy, Columbus, OH (United States); Becker Tjus, J.; Bos, F.; Eichmann, B.; Kroll, M.; Mandelartz, M.; Schoeneberg, S.; Tenholt, F. [Ruhr-Universitaet Bochum, Fakultaet fuer Physik and Astronomie, Bochum (Germany); Becker, K.H.; Bindig, D.; Helbing, K.; Hickford, S.; Hoffmann, R.; Kopper, S.; Lauber, F.; Naumann, U.; Obertacke Pollmann, A.; Soldin, D. [University of Wuppertal, Department of Physics, Wuppertal (Germany); BenZvi, S.; Cross, R. [University of Rochester, Department of Physics and Astronomy, Rochester, NY (United States); Berley, D.; Blaufuss, E.; Cheung, E.; Felde, J.; Friedman, E.; Hellauer, R.; Hoffman, K.D.; Maunu, R.; Olivas, A.; Schmidt, T.; Song, M.; Sullivan, G.W. [University of Maryland, Department of Physics, College Park, MD (United States); Besson, D.Z. [University of Kansas, Department of Physics and Astronomy, Lawrence, KS (United States); Binder, G.; Gerhardt, L.; Klein, S.R.; Miarecki, S.; Tatar, J. [University of California, Department of Physics, Berkeley, CA (United States); Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Collaboration: IceCube Collaboration; and others

    2017-02-15

    We present the results of the first IceCube search for dark matter annihilation in the center of the Earth. Weakly interacting massive particles (WIMPs), candidates for dark matter, can scatter off nuclei inside the Earth and fall below its escape velocity. Over time the captured WIMPs will be accumulated and may eventually self-annihilate. Among the annihilation products only neutrinos can escape from the center of the Earth. Large-scale neutrino telescopes, such as the cubic kilometer IceCube Neutrino Observatory located at the South Pole, can be used to search for such neutrino fluxes. Data from 327 days of detector livetime during 2011/2012 were analyzed. No excess beyond the expected background from atmospheric neutrinos was detected. The derived upper limits on the annihilation rate of WIMPs in the Earth and the resulting muon flux are an order of magnitude stronger than the limits of the last analysis performed with data from IceCube's predecessor AMANDA. The limits can be translated in terms of a spin-independent WIMP-nucleon cross section. For a WIMP mass of 50 GeV this analysis results in the most restrictive limits achieved with IceCube data. (orig.)

  19. Effect of rare earth elements on the distribution of photosynthate in sugar beet

    International Nuclear Information System (INIS)

    Bai Baozhang; Yang Yuchang; Meng Xianju; Wang Yuefeng; Bai Song

    1995-01-01

    The effect of rare earth elements on the distribution of photosynthate in sugar beet was studied. The results indicated that rare earth elements stimulated CO 2 assimilation, increased the ratio of root and tops (R/T), improved the distribution of photosynthate and stimulated the transport of organic matter from leaf to root of sugar beet plant. The treatment with 0.05% was shown to have the most significant effect among all the treatments

  20. New possibilities in supernova accretion phase from dense matter effect

    Science.gov (United States)

    Chakraborty, S.; Mirizzi, A.; Saviano, N.

    2012-07-01

    We carry out a detailed analysis of the supernova (SN) neutrino flavor evolution during the accretion phase (at post-bounce times tpb Mikheyev-Smirnov-Wolfenstein effect in the SN mantle and Earth matter effects, can reveal the neutrino mass hierarchy in the likely case that the mixing angle θ13 is not very small.

  1. Earth Effects and Mass Hierarchy with Supernova Neutrinos

    International Nuclear Information System (INIS)

    Dasgupta, Basudeb

    2009-01-01

    Collective neutrino flavor transformations take place deep inside a supernova if the neutrino mass hierarchy is inverted, even for extremely small values of θ 13 . We show that the presence (or absence) of Earth matter effects in antineutrino signal is directly related to the absence (or presence) of these collective effects, when the mixing angle θ 13 is small. Thus a neutrino signal from a galactic supernova may enable us to distinguish between the hierarchies even for small values of θ 13 .

  2. Measurement of atmospheric neutrino oscillations and matter effects with PINGU

    Energy Technology Data Exchange (ETDEWEB)

    Coenders, Stefan; Euler, Sebastian; Krings, Kai; Vehring, Markus; Wallraff, Marius; Wiebusch, Christopher [RWTH Aachen Univ. (Germany). III. Physikalisches Inst.; Collaboration: IceCube-Collaboration

    2013-07-01

    With IceCube's low-energy extension DeepCore the first significant effects of atmospheric neutrino oscillations have been observed. The planned ''Precision Icecube Next Generation Upgrade'' (PINGU) inside DeepCore will lower the energy threshold to a few GeV, where matter effects of neutrino oscillations have to be taken into account. The Mikheyev-Smirnov-Wolfenstein (MSW) effect modifies the mixing between flavor and mass eigenstates of the neutrinos, resulting in stronger oscillations. Furthermore, neutrinos when passing through the Earth core experience parametric enhancement due to multiple discontinuities in the electron density. In this talk the effects of matter oscillations and the capabilities to measure these effects with PINGU are investigated.

  3. [Transparent evolution of the energy/matter interactions on earth: from gas whirlwind to technogenic civilization].

    Science.gov (United States)

    Pechurkin, N S; Shuvaev, A N

    2015-01-01

    The paper presents the idea of transparent evolution through the long-term reaction of the planet Earth on the external flow of radiant energy from the Sun. Due to limitations of matter on Earth, as well as on any other planet, the continuous pumping flow of radiant energy was shown to lead to cyclization and transport of substance on emerging gradients. The evolution of energy-matter interaction follows the path of capturing and transferring more energy by the fewer matter, i.e., the path of growth of the amount of energy used by each unit mass. For this indicator, the least effective mass transfer is a simple mass transfer as vortices of gases, in the gradients of temperature and pressure, which occurred on the primary surface of the planet. A long-term natural selection related to the accumulation of water on the planet has played a special role in developing the interaction of energy and matter. Phase transformations (ice, water, vapor) and mechanical transfers are the most common energy-matter processes. Based on water cycles, cyclic transports and transformations, chemical transformation of substances became possible developing over time into a biological transformation. This kind of the interaction of energy and matter is most efficient. In particular, during photosynthesis the energy of our star "is captured and utilized" in the most active part of the spectrum of its radiation. In the process of biological evolution of heterotrophs, a rise (by a factor of hundreds) in the coefficient that characterizes the intensity of energy exchange from protozoa to mammals is most illustratory. The development and the current dominance of humans as the most energy-using active species in capturing the energy and meaningful organization of its new flows especially on the basis of organic debris of former biospheres is admirable, but quite natural from the energy positions. In the course of technological evolution of humankind, the measure of the intensity of energy for

  4. Characterization of Soil Organic Matter from African Dark Earth (AfDE) Soils

    Science.gov (United States)

    Plante, A. F.; Fujiu, M.; Ohno, T.; Solomon, D.; Lehmann, J.; Fraser, J. A.; Leach, M.; Fairhead, J.

    2014-12-01

    Anthropogenic Dark Earths are soils generated through long-term human inputs of organic and pyrogenic materials. These soils were originally discovered in the Amazon, and have since been found in Australia and in this case in Africa. While tropical soils are typically characterized by low soil organic matter (SOM) concentrations, African Dark Earths (AfDE) are black, highly fertile and carbon-rich soils formed through an extant but ancient soil management system. The objective of this study was to characterize the organic matter accumulated in AfDE and contrast it with non-AfDE soils. Characterization of bulk soil organic matter of several (n=11) AfDE and non-AfDE pairs of surface (0-15 cm) soils using thermal analysis techniques (TG-DSC-EGA) resulted in substantial differences in SOM composition and the presence of pyrogenic C. Such pyrogenic organic matter is generally considered recalcitrant, but the fertility gains in AfDE are generated by labile, more rapidly cycling pools of SOM. As a result, we characterized hot water- and pyrophosphate-extractable pools of SOM using fluorescence (EEM/PARAFAC) and high resolution mass spectrometry (FT-ICR-MS). EEM/PARAFAC data suggests that AfDE samples had a greater fraction of their DOM that was more humic-like than the paired non-AfDE samples. Similarly, FT-ICR-MS analyses of extracts suggest that differences among the sites analyzed were larger than between the paired AfDE and non-AfDE extracts. Overall, in spite of substantial differences in the composition of bulk SOM, the extractable fractions appear to be relatively similar between the AfDE and non-AfDE soils.

  5. Ligand extraction of rare earth elements from aquifer sediments: Implications for rare earth element complexation with organic matter in natural waters

    Science.gov (United States)

    Tang, Jianwu; Johannesson, Karen H.

    2010-12-01

    The ability of organic matter as well as carbonate ions to extract rare earth elements (REEs) from sandy sediments of a Coastal Plain aquifer was investigated for unpurified organic matter from different sources (i.e., Mississippi River natural organic matter, Aldrich humic acid, Nordic aquatic fulvic acid, Suwannee River fulvic acid, and Suwannee River natural organic matter) and for extraction solutions containing weak (i.e., CH 3COO -) or strong (i.e., CO32-) ligands. The experimental results indicate that, in the absence of strong REE complexing ligands in solution, the amount of REEs released from the sand is small and the fractionation pattern of the released REEs appears to be controlled by the surface stability constants for REE sorption with Fe(III) oxides/oxyhydroxides. In the presence of strong solution complexing ligands, however, the amount and the fractionation pattern of the released REEs reflect the strength and variation of the stability constants of the dominant aqueous REE species across the REE series. The varying amount of REEs extracted by the different organic matter employed in the experiments indicates that organic matter from different sources has different complexing capacity for REEs. However, the fractionation pattern of REEs extracted by the various organic matter used in our experiments is remarkable consistent, being independent of the source and the concentration of organic matter used, as well as solution pH. Because natural aquifer sand and unpurified organic matter were used in our experiments, our experimental conditions are more broadly similar to natural systems than many previous laboratory experiments of REE-humic complexation that employed purified humic substances. Our results suggest that the REE loading effect on REE-humic complexation is negligible in natural waters as more abundant metal cations (e.g., Fe, Al) out-compete REEs for strong binding sites on organic matter. More specifically, our results indicate that REE

  6. A Novel Approach to Teaching and Understanding Transformations of Matter in Dynamic Earth Systems

    Science.gov (United States)

    Clark, Scott K.; Sibley, Duncan F.; Libarkin, Julie C.; Heidemann, Merle

    2009-01-01

    The need to engage K-12 and post-secondary students in considering the Earth as a dynamic system requires explicit discussion of system characteristics. Fundamentally, dynamic systems involve the movement and change of matter, often through processes that are difficult to see and comprehend. We introduce a novel instructional method, termed…

  7. Matter effects on the flavor conversions of solar neutrinos and high-energy astrophysical neutrinos

    Science.gov (United States)

    Huang, Guo-yuan; Liu, Jun-Hao; Zhou, Shun

    2018-06-01

    Can we observe the solar eclipses in the neutrino light? In principle, this is possible by identifying the lunar matter effects on the flavor conversions of solar neutrinos when they traverse the Moon before reaching the detectors at the Earth. Unfortunately, we show that the lunar matter effects on the survival probability of solar 8B neutrinos are suppressed by an additional factor of 1.2%, compared to the day-night asymmetry. However, we point out that the matter effects on the flavor conversions of high-energy astrophysical neutrinos, when they propagate through the Sun, can be significant. Though the flavor composition of high-energy neutrinos can be remarkably modified, it is quite challenging to observe such effects even in the next-generation of neutrino telescopes.

  8. Dark Matter Searches

    International Nuclear Information System (INIS)

    Moriyama, Shigetaka

    2008-01-01

    Recent cosmological as well as historical observations of rotational curves of galaxies strongly suggest the existence of dark matter. It is also widely believed that dark matter consists of unknown elementary particles. However, astrophysical observations based on gravitational effects alone do not provide sufficient information on the properties of dark matter. In this study, the status of dark matter searches is investigated by observing high-energy neutrinos from the sun and the earth and by observing nuclear recoils in laboratory targets. The successful detection of dark matter by these methods facilitates systematic studies of its properties. Finally, the XMASS experiment, which is due to start at the Kamioka Observatory, is introduced

  9. Effect of gravitational focusing on annual modulation in dark-matter direct-detection experiments.

    Science.gov (United States)

    Lee, Samuel K; Lisanti, Mariangela; Peter, Annika H G; Safdi, Benjamin R

    2014-01-10

    The scattering rate in dark-matter direct-detection experiments should modulate annually due to Earth's orbit around the Sun. The rate is typically thought to be extremized around June 1, when the relative velocity of Earth with respect to the dark-matter wind is maximal. We point out that gravitational focusing can alter this modulation phase. Unbound dark-matter particles are focused by the Sun's gravitational potential, affecting their phase-space density in the lab frame. Gravitational focusing can result in a significant overall shift in the annual-modulation phase, which is most relevant for dark matter with low scattering speeds. The induced phase shift for light O(10)  GeV dark matter may also be significant, depending on the threshold energy of the experiment.

  10. Multifunctional phenomena in rare-earth intermetallic compounds with a laves phase structure: giant magnetostriction and magnetocaloric effect

    Czech Academy of Sciences Publication Activity Database

    Tereshina, I.; Cwik, J.; Tereshina, Evgeniya; Politova, G.; Burkhanov, G.; Chzhan, V.; Ilyushin, A.; Miller, M.; Zaleski, A.; Nenkov, K.; Schultz, L.

    2014-01-01

    Roč. 50, č. 11 (2014), s. 2504604 ISSN 0018-9464 Institutional support: RVO:68378271 Keywords : giant magnetostriction * Laves phase structure * magnetic anisotropy * magnetocaloric effect * rare-earth intermetallic Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.386, year: 2014

  11. PHYS: Division of Physical Chemistry 258 - Properties and Origins of Cometary and Asteroidal Organic Matter Delivered to the Early Earth

    Science.gov (United States)

    Messenger, Scott; Nguyen, Ann

    2017-01-01

    Comets and asteroids may have contributed much of the Earth's water and organic matter. The Earth accretes approximately 4x10(exp 7) Kg of dust and meteorites from these sources every year. The least altered meteorites contain complex assemblages of organic compounds and abundant hydrated minerals. These carbonaceous chondrite meteorites probably derive from asteroids that underwent hydrothermal processing within the first few million years after their accretion. Meteorite organics show isotopic and chemical signatures of low-T ion-molecule and grain-surface chemistry and photolysis of icy grains that occurred in cold molecular clouds and the outer protoplanetary disk. These signatures have been overprinted by aqueously mediated chemistry in asteroid parent bodies, forming amino acids and other prebiotic molecules. Comets are much richer in organic matter but it is less well characterized. Comet dust collected in the stratosphere shows larger H and N isotopic anomalies than most meteorites, suggesting better preservation of primordial organics. Rosetta studies of comet 67P coma dust find complex organic matter that may be related to the macromolecular material that dominates the organic inventory of primitive meteorites. The exogenous organic material accreting on Earth throughout its history is made up of thousands of molecular species formed in diverse processes ranging from circumstellar outflows to chemistry at near absolute zero in dark cloud cores and the formative environment within minor planets. NASA and JAXA are currently flying sample return missions to primitive, potentially organic-rich asteroids. The OSIRIS-REx and Hayabusa2 missions will map their target asteroids, Bennu and Ryugu, in detail and return regolith samples to Earth. Laboratory analyses of these pristine asteroid samples will provide unprecedented views of asteroidal organic matter relatively free of terrestrial contamination within well determined geological context. Studies of

  12. Solid Matter

    CERN Document Server

    Angelo, Joseph A

    2011-01-01

    Supported by a generous quantity of full-color illustrations and interesting sidebars, Solid Matter introduces the basic characteristics and properties of solid matter. It briefly describes the cosmic connection of the elements, leading readers through several key events in human pre-history that resulted in more advanced uses of matter in the solid state. Chapters include:. -Solid Matter: An Initial Perspective. -Physical Behavior of Matter. -The Gravity of Matter. -Fundamentals of Materials Science. -Rocks and Minerals. -Metals. -Building Materials. -Carbon Earth's Most Versatile Element. -S

  13. Treatment of solar neutrino-oscillations in solar matter. The MSW effect

    International Nuclear Information System (INIS)

    Messiah, A.

    1986-01-01

    Mikheyev and Smirnov, following Wolfenstein's theory of neutrino oscillations in the presence of matter, have found that the change of flavour of solar neutrinos may be spectacularly enhanced in the presence of solar matter, when the parameters of the neutrino mass operator fall in a suitable range (MSW effect). It is shown that this effect can be readily deduced from the adiatic solution of the equation of flavour evolution. A complete study of the two-flavour case is given, permitting to calculate, for any set of values of the mass operator parameters, the ν e suppression factor at the site of detection on earth. The adiabatic approximation holds over a wide range of the parameters, leading to especially simple expressions. Our calculations cover the whole range, including domains where the adiabatic approximation is no longer valid. Some of the results, presented in a form most suited for an analysis of solar neutrino experiments, are displayed for illustration and discussed. 7 refs

  14. Cosmology and the expanding Earth hypothesis

    International Nuclear Information System (INIS)

    Tryon, E.P.

    1983-01-01

    The standard model of cosmology is briefly presented, together with a recent conjecture that the initial matter in the universe might have been spontaneously created from nothing as a result of relativistic quantum physics. The possibility of Earth expansion from a continuing creation of matter is then considered. A critique is presented of efforts to relate Earth expansion to the Hubble expansion of the universe. Possible changes in Earth radius as a result of diminishing gravity are also discussed

  15. Dark Matter Effective Theory

    DEFF Research Database (Denmark)

    Del Nobile, Eugenio; Sannino, Francesco

    2012-01-01

    We organize the effective (self)interaction terms for complex scalar dark matter candidates which are either an isosinglet, isodoublet or an isotriplet with respect to the weak interactions. The classification has been performed ordering the operators in inverse powers of the dark matter cutoff...... scale. We assume Lorentz invariance, color and charge neutrality. We also introduce potentially interesting dark matter induced flavor-changing operators. Our general framework allows for model independent investigations of dark matter properties....

  16. Effects of Majorana physics on the UHE ν{sub τ} flux traversing the Earth

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, Lucia [Universidad de la Republica, Instituto de Fisica, Facultad de Ingenieria, Montevideo (Uruguay); Romero, Ismael; Zapata, Gabriel; Sampayo, Oscar A. [Universidad Nacional de Mar del Plata, Instituto de Investigaciones Fisicas de Mar del Plata (IFIMAR), CONICET, UNMDP, Departamento de Fisica, Mar del Plata (Argentina)

    2017-02-15

    We study the effects produced by sterile Majorana neutrinos on the ν{sub τ} flux traversing the Earth, considering the interaction between the Majorana neutrinos and the standard matter as modeled by an effective theory. The surviving tau-neutrino flux is calculated using transport equations including Majorana neutrino production and decay. We compare our results with the pure Standard Model interactions, computing the surviving flux for different values of the effective lagrangian couplings, considering the detected flux by IceCube for an operation time of 10 years, and Majorana neutrinos with mass m{sub N} ∝ m{sub τ}. (orig.)

  17. Particle Dark Matter constraints: the effect of Galactic uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Benito, Maria; Bernal, Nicolás; Iocco, Fabio [ICTP South American Institute for Fundamental Research Instituto de Física Teórica - Universidade Estadual Paulista (UNESP) Rua Dr. Bento Teobaldo Ferraz 271, 01140-070 São Paulo, SP Brazil (Brazil); Bozorgnia, Nassim; Calore, Francesca, E-mail: mariabenitocst@gmail.com, E-mail: nicolas.bernal@uan.edu.co, E-mail: n.bozorgnia@uva.nl, E-mail: calore@lapth.cnrs.fr, E-mail: fabio.iocco.astro@gmail.com [GRAPPA Institute, Institute for Theoretical Physics Amsterdam and Delta Institute for Theoretical Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands)

    2017-02-01

    Collider, space, and Earth based experiments are now able to probe several extensions of the Standard Model of particle physics which provide viable dark matter candidates. Direct and indirect dark matter searches rely on inputs of astrophysical nature, such as the local dark matter density or the shape of the dark matter density profile in the target in object. The determination of these quantities is highly affected by astrophysical uncertainties. The latter, especially those for our own Galaxy, are ill-known, and often not fully accounted for when analyzing the phenomenology of particle physics models. In this paper we present a systematic, quantitative estimate of how astrophysical uncertainties on Galactic quantities (such as the local galactocentric distance, circular velocity, or the morphology of the stellar disk and bulge) propagate to the determination of the phenomenology of particle physics models, thus eventually affecting the determination of new physics parameters. We present results in the context of two specific extensions of the Standard Model (the Singlet Scalar and the Inert Doublet) that we adopt as case studies for their simplicity in illustrating the magnitude and impact of such uncertainties on the parameter space of the particle physics model itself. Our findings point toward very relevant effects of current Galactic uncertainties on the determination of particle physics parameters, and urge a systematic estimate of such uncertainties in more complex scenarios, in order to achieve constraints on the determination of new physics that realistically include all known uncertainties.

  18. DaMaSCUS-CRUST: Dark Matter Simulation Code for Underground Scatterings - Crust Edition

    Science.gov (United States)

    Emken, Timon; Kouvaris, Chris

    2018-03-01

    DaMaSCUS-CRUST determines the critical cross-section for strongly interacting DM for various direct detection experiments systematically and precisely using Monte Carlo simulations of DM trajectories inside the Earth's crust, atmosphere, or any kind of shielding. Above a critical dark matter-nucleus scattering cross section, any terrestrial direct detection experiment loses sensitivity to dark matter, since the Earth crust, atmosphere, and potential shielding layers start to block off the dark matter particles. This critical cross section is commonly determined by describing the average energy loss of the dark matter particles analytically. However, this treatment overestimates the stopping power of the Earth crust; therefore, the obtained bounds should be considered as conservative. DaMaSCUS-CRUST is a modified version of DaMaSCUS (ascl:1706.003) that accounts for shielding effects and returns a precise exclusion band.

  19. Effective description of dark matter self-interactions in small dark matter haloes

    International Nuclear Information System (INIS)

    Kummer, Janis

    2017-07-01

    Self-interacting dark matter may have striking astrophysical signatures, such as observ- able offsets between galaxies and dark matter in merging galaxy clusters. Numerical N-body simulations used to predict such observables typically treat the galaxies as collisionless test particles, a questionable assumption given that each galaxy is embedded in its own dark matter halo. To enable a more accurate treatment we develop an effective description of small dark matter haloes taking into account the two major effects due to dark matter self-scatterings: deceleration and evaporation. We point out that self-scatterings can have a sizeable impact on the trajectories of galaxies, diminishing the separation between galaxies and dark matter in merging clusters. This effect depends sensitively on the underlying particle physics, in particular the angular dependence of the self-scattering cross section, and cannot be predicted from the momentum transfer cross section alone.

  20. Flooding Effect on Earth Walls

    Directory of Open Access Journals (Sweden)

    Meysam Banimahd

    2010-12-01

    Full Text Available Earth building is a sustainable, environmentally friendly and economical method of construction that has been used worldwide for many centuries. For the past three decades, earth has seen a revival as a building material for a modern construction method due to its benefits in terms of low carbon content, low cost and energy involved during construction, as well as the fact that it is a sustainable technology of building. Climate change is influencing precipitation levels and patterns around the world, and as a consequence, flood risk is increasing rapidly. When flooding occurs, earth buildings are exposed to water by submersion, causing an increase in the degree of saturation of the earth structures and therefore a decrease of the suction between particles. This study investigated the effect of cycles of flooding (consecutive events of flooding followed by dry periods on earth walls. A series of characterization tests were carried out to obtain the physical and mechanical properties of the studied earth material. In a second stage, Flooding Simulation Tests (FST were performed to explore the earth walls’ response to repeated flooding events. The results obtained for the tested earth wall/samples with reinforced material (straw reveal hydraulic hysteresis when wall/samples are subject to cycles of wetting and drying.

  1. Rare earth elements and neodymium isotopes in sedimentary organic matter

    Science.gov (United States)

    Freslon, Nicolas; Bayon, Germain; Toucanne, Samuel; Bermell, Sylvain; Bollinger, Claire; Chéron, Sandrine; Etoubleau, Joel; Germain, Yoan; Khripounoff, Alexis; Ponzevera, Emmanuel; Rouget, Marie-Laure

    2014-09-01

    We report rare earth element (REE) and neodymium (Nd) isotope data for the organic fraction of sediments collected from various depositional environments, i.e. rivers (n = 25), estuaries (n = 18), open-ocean settings (n = 15), and cold seeps (n = 12). Sedimentary organic matter (SOM) was extracted using a mixed hydrogen peroxide/nitric acid solution (20%-H2O2-0.02 M-HNO3), after removal of carbonate and oxy-hydroxide phases with dilute hydrochloric acid (0.25 M-HCl). A series of experimental tests indicate that extraction of sedimentary organic compounds using H2O2 may be complicated occasionally by partial dissolution of sulphide minerals and residual carbonates. However, this contamination is expected to be minor for REE because measured concentrations in H2O2 leachates are about two-orders of magnitude higher than in the above mentioned phases. The mean REE concentrations determined in the H2O2 leachates for samples from rivers, estuaries, coastal seas and open-ocean settings yield relatively similar levels, with ΣREE = 109 ± 86 ppm (mean ± s; n = 58). The organic fractions leached from cold seep sediments display even higher concentration levels (285 ± 150 ppm; mean ± s; n = 12). The H2O2 leachates for most sediments exhibit remarkably similar shale-normalized REE patterns, all characterized by a mid-REE enrichment compared to the other REE. This suggests that the distribution of REE in leached sedimentary organic phases is controlled primarily by biogeochemical processes, rather than by the composition of the source from which they derive (e.g. pore, river or sea-water). The Nd isotopic compositions for organic phases leached from river sediments are very similar to those for the corresponding detrital fractions. In contrast, the SOM extracted from marine sediments display εNd values that typically range between the εNd signatures for terrestrial organic matter (inferred from the analysis of the sedimentary detrital fractions) and marine organic matter

  2. Thermal Properties of Matter

    Science.gov (United States)

    Khachan, Joe

    2018-02-01

    The ancient Greeks believed that all matter was composed of four elements: earth, water, air, and fire. By a remarkable coincidence (or perhaps not), today we know that there are four states of matter: solids (e.g. earth), liquids (e.g. water), gasses (e.g. air) and plasma (e.g. ionized gas produced by fire). The plasma state is beyond the scope of this book and we will only look at the first three states. Although on the microscopic level all matter is made from atoms or molecules, everyday experience tells us that the three states have very different properties. The aim of this book is to examine some of these properties and the underlying physics.

  3. Matter oscillations and solar neutrinos: A review of the MSW [Mikheyev-Smirnov-Wolfenstein] effect

    International Nuclear Information System (INIS)

    Rosen, S.P.; Gelb, J.M.

    1986-01-01

    We review the theory of the Mikheyev-Smirnov-Wolfenstein effect, in which matter oscillations can greatly enhance ''in vacuo'' neutrino oscillations, and we examine its consequences for the solar neutrino problem. Using a two-flavor model, we discuss the solutions in the Δm 2 -sin 2 2Θ parameter space for the 37 Cl experiment, and describe their predictions for the 71 Ga experiment and for the spectrum of electron-neutrinos arriving at earth. We also comment on the three-flavor case

  4. Matter oscillations: Neutrino transformation and regeneration in the earth

    International Nuclear Information System (INIS)

    Baltz, A.J.; Weneser, J.

    1987-01-01

    Transformation and regeneration phenomena are calculated to result from transmission through the Earth of neutrinos with E(MeV)/Δm 2 (eV) 2 in the vicinity of 10 6 to 10 7 . As a result, large time-of-night and seasonal variations are predicted for various solar neutrino experiments in this parameter range. Analagous effects are predicted for terrestrial cosmic ray and accelerator experiments

  5. High spin effects in superdense matter

    International Nuclear Information System (INIS)

    Bowers, R.L.; Gleeson, A.M.; Pedigo, R.D.

    1978-04-01

    A model of relativistic interacting superdense matter with vector, scalar and symmetric second rank tensor exchange is developed. The Green's functions of the model are solved in the self consistent Hartree approximation. The contributions of the symmetric second rank tensor are emphasized. It is found that these high spin contributions effect the superdense matter at densities just beyond those predicted to occur in neutron star matter or nuclear collisions. The spin-two effects do produce an unusual asymptotic dependence, p = - 1 / 3 epsilon. This effect is examined in a simple model of the early universe

  6. Diurnal modulation signal from dissipative hidden sector dark matter

    Directory of Open Access Journals (Sweden)

    R. Foot

    2015-09-01

    Full Text Available We consider a simple generic dissipative dark matter model: a hidden sector featuring two dark matter particles charged under an unbroken U(1′ interaction. Previous work has shown that such a model has the potential to explain dark matter phenomena on both large and small scales. In this framework, the dark matter halo in spiral galaxies features nontrivial dynamics, with the halo energy loss due to dissipative interactions balanced by a heat source. Ordinary supernovae can potentially supply this heat provided kinetic mixing interaction exists with strength ϵ∼10−9. This type of kinetically mixed dark matter can be probed in direct detection experiments. Importantly, this self-interacting dark matter can be captured within the Earth and shield a dark matter detector from the halo wind, giving rise to a diurnal modulation effect. We estimate the size of this effect for detectors located in the Southern hemisphere, and find that the modulation is large (≳10% for a wide range of parameters.

  7. Mass, Energy, Space And Time System Theory---MEST A way to help our earth

    Science.gov (United States)

    Cao, Dayong

    2009-03-01

    There are two danger to our earth. The first, the sun will expand to devour our earth, for example, the ozonosphere of our earth is be broken; The second, the asteroid will impact near our earth. According to MEST, there is a interaction between Black hole (and Dark matter-energy) and Solar system. The orbit of Jupiter is a boundary of the interaction between Black hole (and Dark matter-energy) and Solar system. Because there are four terrestrial planets which is mass-energy center as solar system, and there are four or five Jovian planets which is gas (space-time) center as black hole system. According to MEST, dark matter-energy take the velocity of Jupiter gose up. So there are a lot of asteroids and dark matter-energy near the orbit of Jupiter-the boundary. Dark matter-energy can change the orbit of asteroid, and take it impacted near our earth. Because the Dark matter-energy will pressure the Solar system. It is a inverse process with sun's expandedness. So the ``two danger'' is from a new process of the balance system between Black hole (and Dark matter-energy) and Solar system. According to MEST, We need to find the right point for our earth in the ``new process of the balance system.''

  8. Matter oscillations and solar neutrinos: A review of the MSW (Mikheyev-Smirnov-Wolfenstein) effect

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, S.P.; Gelb, J.M.

    1986-07-16

    We review the theory of the Mikheyev-Smirnov-Wolfenstein effect, in which matter oscillations can greatly enhance ''in vacuo'' neutrino oscillations, and we examine its consequences for the solar neutrino problem. Using a two-flavor model, we discuss the solutions in the ..delta..m/sup 2/-sin/sup 2/2THETA parameter space for the /sup 37/Cl experiment, and describe their predictions for the /sup 71/Ga experiment and for the spectrum of electron-neutrinos arriving at earth. We also comment on the three-flavor case.

  9. Possible resonance effect of axionic dark matter in Josephson junctions.

    Science.gov (United States)

    Beck, Christian

    2013-12-06

    We provide theoretical arguments that dark-matter axions from the galactic halo that pass through Earth may generate a small observable signal in resonant S/N/S Josephson junctions. The corresponding interaction process is based on the uniqueness of the gauge-invariant axion Josephson phase angle modulo 2π and is predicted to produce a small Shapiro steplike feature without externally applied microwave radiation when the Josephson frequency resonates with the axion mass. A resonance signal of so far unknown origin observed by C. Hoffmann et al. [Phys. Rev. B 70, 180503(R) (2004)] is consistent with our theory and can be interpreted in terms of an axion mass m(a)c2=0.11  meV and a local galactic axionic dark-matter density of 0.05  GeV/cm3. We discuss future experimental checks to confirm the dark-matter nature of the observed signal.

  10. Identifying Neutrino Mass Hierarchy at Extremely Small θ13 through Earth Matter Effects in a Supernova Signal

    International Nuclear Information System (INIS)

    Dasgupta, Basudeb; Dighe, Amol; Mirizzi, Alessandro

    2008-01-01

    Collective neutrino flavor transformations deep inside a supernova are sensitive to the neutrino mass hierarchy even at extremely small values of θ 13 . Exploiting this effect, we show that comparison of the antineutrino signals from a galactic supernova in two megaton class water Cherenkov detectors, one of which is shadowed by Earth, will enable us to distinguish between the hierarchies if sin 2 θ 13 -5 , where long baseline neutrino experiments would be ineffectual

  11. DaMaSCUS: the impact of underground scatterings on direct detection of light dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Emken, Timon; Kouvaris, Chris, E-mail: emken@cp3.sdu.dk, E-mail: kouvaris@cp3.sdu.dk [CP3-Origins, University of Southern Denmark, Campusvej 55, DK-5230 Odense (Denmark)

    2017-10-01

    Conventional dark matter direct detection experiments set stringent constraints on dark matter by looking for elastic scattering events between dark matter particles and nuclei in underground detectors. However these constraints weaken significantly in the sub-GeV mass region, simply because light dark matter does not have enough energy to trigger detectors regardless of the dark matter-nucleon scattering cross section. Even if future experiments lower their energy thresholds, they will still be blind to parameter space where dark matter particles interact with nuclei strongly enough that they lose enough energy and become unable to cause a signal above the experimental threshold by the time they reach the underground detector. Therefore in case dark matter is in the sub-GeV region and strongly interacting, possible underground scatterings of dark matter with terrestrial nuclei must be taken into account because they affect significantly the recoil spectra and event rates, regardless of whether the experiment probes DM via DM-nucleus or DM-electron interaction. To quantify this effect we present the publicly available Dark Matter Simulation Code for Underground Scatterings (DaMaSCUS), a Monte Carlo simulator of DM trajectories through the Earth taking underground scatterings into account. Our simulation allows the precise calculation of the density and velocity distribution of dark matter at any detector of given depth and location on Earth. The simulation can also provide the accurate recoil spectrum in underground detectors as well as the phase and amplitude of the diurnal modulation caused by this shadowing effect of the Earth, ultimately relating the modulations expected in different detectors, which is important to decisively conclude if a diurnal modulation is due to dark matter or an irrelevant background.

  12. DaMaSCUS: the impact of underground scatterings on direct detection of light dark matter

    International Nuclear Information System (INIS)

    Emken, Timon; Kouvaris, Chris

    2017-01-01

    Conventional dark matter direct detection experiments set stringent constraints on dark matter by looking for elastic scattering events between dark matter particles and nuclei in underground detectors. However these constraints weaken significantly in the sub-GeV mass region, simply because light dark matter does not have enough energy to trigger detectors regardless of the dark matter-nucleon scattering cross section. Even if future experiments lower their energy thresholds, they will still be blind to parameter space where dark matter particles interact with nuclei strongly enough that they lose enough energy and become unable to cause a signal above the experimental threshold by the time they reach the underground detector. Therefore in case dark matter is in the sub-GeV region and strongly interacting, possible underground scatterings of dark matter with terrestrial nuclei must be taken into account because they affect significantly the recoil spectra and event rates, regardless of whether the experiment probes DM via DM-nucleus or DM-electron interaction. To quantify this effect we present the publicly available Dark Matter Simulation Code for Underground Scatterings (DaMaSCUS), a Monte Carlo simulator of DM trajectories through the Earth taking underground scatterings into account. Our simulation allows the precise calculation of the density and velocity distribution of dark matter at any detector of given depth and location on Earth. The simulation can also provide the accurate recoil spectrum in underground detectors as well as the phase and amplitude of the diurnal modulation caused by this shadowing effect of the Earth, ultimately relating the modulations expected in different detectors, which is important to decisively conclude if a diurnal modulation is due to dark matter or an irrelevant background.

  13. Effect of Tb and Al substitution within the rare earth and cobalt sublattices on magnetothermal properties of Dy.sub.0.5./sub.Ho.sub.0.5./sub.Co.sub.2./sub.

    Czech Academy of Sciences Publication Activity Database

    Chzhan, V.B.; Tereshina, Evgeniya; Mikhailova, A.B.; Politova, G.A.; Tereshina, I. S.; Kozlov, V.I.; Ćwik, J.; Nenkov, K.; Alekseeva, O.A.; Filimonov, A.V.

    2017-01-01

    Roč. 432, June (2017), s. 461-465 ISSN 0304-8853 R&D Projects: GA ČR GA16-03593S Institutional support: RVO:68378271 Keywords : rare- earth intermetallics * laves phase * heat capacity * magnetocaloric effect Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 2.630, year: 2016

  14. Muon Flux Limits for Majorana Dark Matter Particles

    DEFF Research Database (Denmark)

    Belotsky, Konstantin; Khlopov, Maxim; Kouvaris, Christoforos

    2009-01-01

    We analyze the effects of capture of dark matter (DM) particles, with successive annihilations, predicted in the minimal walking technicolor model (MWT) by the Sun and the Earth. We show that the Super-Kamiokande (SK) upper limit on excessive muon flux disfavors the mass interval between 100-200 Ge...

  15. Planck-scale effects on WIMP dark matter

    Directory of Open Access Journals (Sweden)

    Sofiane M Boucenna

    2014-01-01

    Full Text Available There exists a widely known conjecture that gravitational effects violate global symmetries. We study the effect of global-symmetry violating higher-dimension operators induced by Planck-scale physics on the properties of WIMP dark matter. Using an effective description, we show that the lifetime of the WIMP dark matter candidate can satisfy cosmological bounds under reasonable assumptions regarding the strength of the dimension-five operators. On the other hand, the indirect WIMP dark matter detection signal is significantly enhanced due to new decay channels.

  16. Diurnal modulation due to self-interacting mirror and hidden sector dark matter

    International Nuclear Information System (INIS)

    Foot, R.

    2012-01-01

    Mirror and more generic hidden sector dark matter models can simultaneously explain the DAMA, CoGeNT and CRESST-II dark matter signals consistently with the null results of the other experiments. This type of dark matter can be captured by the Earth and shield detectors because it is self-interacting. This effect will lead to a diurnal modulation in dark matter detectors. We estimate the size of this effect for dark matter detectors in various locations. For a detector located in the northern hemisphere, this effect is expected to peak in April and can be detected for optimistic parameter choices. The diurnal variation is expected to be much larger for detectors located in the southern hemisphere. In particular, if the CoGeNT detector were moved to e.g. Sierra Grande, Argentina then a 5σ dark matter discovery would be possible in around 30 days of operation

  17. Effect of the spherical Earth on a simple pendulum

    OpenAIRE

    Burko, Lior M.

    2003-01-01

    We consider the period of a simple pendulum in the gravitational field of the spherical Earth. Effectively, gravity is enhanced compared with the often used flat Earth approximation, such that the period of the pendulum is shortened. We discuss the flat Earth approximation, and show when the corrections due to the spherical Earth may be of interest.

  18. Spectral band selection for classification of soil organic matter content

    Science.gov (United States)

    Henderson, Tracey L.; Szilagyi, Andrea; Baumgardner, Marion F.; Chen, Chih-Chien Thomas; Landgrebe, David A.

    1989-01-01

    This paper describes the spectral-band-selection (SBS) algorithm of Chen and Landgrebe (1987, 1988, and 1989) and uses the algorithm to classify the organic matter content in the earth's surface soil. The effectiveness of the algorithm was evaluated comparing the results of classification of the soil organic matter using SBS bands with those obtained using Landsat MSS bands and TM bands, showing that the algorithm was successful in finding important spectral bands for classification of organic matter content. Using the calculated bands, the probabilities of correct classification for climate-stratified data were found to range from 0.910 to 0.980.

  19. Hot Strange Hadronic Matter in an Effective Model

    Institute of Scientific and Technical Information of China (English)

    QIAN Wei-Liang; SU Ru-Keng; SONG Hong-Qiu

    2003-01-01

    An effective model used to describe the strange hadronic matter with nucleons, Λ-hyperons, and Ξ-hyperonsis extended to finite temperature. The extended model is used to study the density, temperature, and strangeness fractiondependence of the effective masses of baryons in the matter. The thermodynamical quantities, such as free energy andpressure, as well as the equation of state of the matter, are given.

  20. Speciation of rare earth elements in different types of soils in China

    International Nuclear Information System (INIS)

    Wang Lijun; Zhang Shen; Gao Xiaojiang; Liu Shujuan

    1997-01-01

    Contents, distribution patterns, physical and chemical speciation of rare earth elements (REEs) in laterite (tropical zone), red earth (middle subtripical earth), yellow brown soil (Northern subtripical earth), cinnamon soil (warm temperature zone), leached chernozem (temperate zone) and albic bleached soil (temperate zone) in China were determined with instrumental neutron activation analysis (INAA). Content and distribution patterns of ERRs are closely related to soil mechanical composition. In laterite, red earth, yellow brown soil and leached chernozem, REEs mainly enrich in fine grain particles or coarser grain partials while in clay particles no such enrichment was found. The distribution patterns of REEs in these soils are consistent with the REE features of their parent rocks. In all the six soils, REEs mainly exist in residual form, and with the increase of atomic number, intermediate REEs (IRRE) have lower proportions of residual form than light REEs (LREE) and heavy REEs (HREE). For the six unstable forms, water soluble form has the lowest proportion. The proportions of exchangeable form, carbonate and specific adsorption form are lower. The proportions of Fe-Min oxides form in different types of soils decrease gradually from Southern China to Northern China following the order: laterite > red earth > yellow brown soil > cinnamon soil, leached chernozem, albic bleached soil. Proportions of bound organic matters are higher and follow the order: Albic bleached soil > leached chernozem > red earth > laterite > yellow brown soil > cinnamon soil. The albic bleached soil has higher proportion of softly bound organic matter form. The leached chernozem has higher proportion of tightly bound organic matter form. Form of bound to organic matter in laterite is almost totally made up of form of softly bound to organic matter

  1. Medium effects in strange quark matter and strange stars

    International Nuclear Information System (INIS)

    Schertler, K.; Greiner, C.; Thoma, M.H.

    1997-01-01

    We investigate the properties of strange quark matter at zero temperature including medium effects. The quarks are considered as quasiparticles which acquire an effective mass generated by the interaction with the other quarks of the dense system. The effective quark masses are derived from the zero momentum limit of the dispersion relations following from an effective quark propagator obtained from resumming one-loop self-energy diagrams in the hard dense loop approximation. This leads to a thermodynamic self-consistent description of strange quark matter as an ideal Fermi gas of quasiparticles. Within this approach we find that medium effects reduce the overall binding energy with respect to 56 Fe of strange quark matter. For typical values of the strong coupling constant (α s >or∼1) strange quark matter is not absolutely stable. The application to pure strange quark matter stars shows that medium effects have, nevertheless, no impact on the mass-radius relation of the stars. However, a phase transition to hadronic matter at the surface of the stars becomes more likely. (orig.)

  2. Evolution of matter and energy on a cosmic and planetary scale

    International Nuclear Information System (INIS)

    Taube, M.

    1985-01-01

    This book covers the following topics: matter and energy; the interplay of elementary particles and elementary forces; the universe; how is it observed here and now; its past and possible future; the origin and nuclear evolution of matter; chemical evolution and the evolution of life; the cosmic phenomena; the eternal cycle of matter on the earth; the flow of energy on the earth; the biosphere; the coupling of matter and the flow of free energy; is the future development of mankind on this planet possible, and the distant future of mankind: terrestrial or cosmic

  3. Hot Strange Hadronic Matter in an Effective Model

    Institute of Scientific and Technical Information of China (English)

    QIANWei-Liang; SURu-Keng; SONGHong-Qiu

    2003-01-01

    An effective model used to describe the strange hadronic matter with nucleons, A-hyperons, and [I]-hyperons is extended to finite temperature. The extended model is used to study the density, temperature, and strangeness fraction dependence of the effective masses of baryons in the matter. The thermodynamical quantities, such as free energy and pressure, as well as the equation of state of the matter, are given.

  4. Inverted dipole feature in directional detection of exothermic dark matter

    International Nuclear Information System (INIS)

    Bozorgnia, Nassim; Gelmini, Graciela B.; Gondolo, Paolo

    2017-01-01

    Directional dark matter detection attempts to measure the direction of motion of nuclei recoiling after having interacted with dark matter particles in the halo of our Galaxy. Due to Earth's motion with respect to the Galaxy, the dark matter flux is concentrated around a preferential direction. An anisotropy in the recoil direction rate is expected as an unmistakable signature of dark matter. The average nuclear recoil direction is expected to coincide with the average direction of dark matter particles arriving to Earth. Here we point out that for a particular type of dark matter, inelastic exothermic dark matter, the mean recoil direction as well as a secondary feature, a ring of maximum recoil rate around the mean recoil direction, could instead be opposite to the average dark matter arrival direction. Thus, the detection of an average nuclear recoil direction opposite to the usually expected direction would constitute a spectacular experimental confirmation of this type of dark matter.

  5. Earth effect in the MSW analysis of the solar neutrino experiments

    International Nuclear Information System (INIS)

    Hata, N.; Langacker, P.

    1993-01-01

    We consider the Earth effect in the combined Mikheyev-Smirnov-Wolfenstein analysis of the solar neutrino experiments including theoretical uncertainties. Using the time-averaged data, the allowed large-angle region extends to much smaller angles than when the Earth effect is ignored. However, the additional constraint from the Kamiokande II day-night data excludes the parameter space most sensitive to the Earth effect, leaving only a small large-angle region close to maximal mixing at 90% C.L. The nonadiabatic solution remains unaffected by the Earth effect and is still preferred

  6. Dynamic ocean-tide effects on Earth's rotation

    Science.gov (United States)

    Dickman, S. R.

    1993-01-01

    This article develops 'broad-band' Liouville equations which are capable of determining the effects on the rotation of the Earth of a periodic excitation even at frequencies as high as semi-diurnal; these equations are then used to predict the rotational effects of altimetric, numerical and 32-constituent spherical harmonic ocean-tide models. The rotational model includes a frequency-dependent decoupled core, the effects of which are especially marked near retrograde diurnal frequencies; and a fully dynamic oceanic response, whose effects appear to be minor despite significant frequency dependence. The model also includes solid-earth effects which are frequency dependent as the result of both anelasticity at long periods and the fluid-core resonance at nearly diurnal periods. The effects of both tidal inertia and relative angular momentum on Earth rotation (polar motion, length of day, 'nutation' and Universal Time) are presented for 32 long- and short-period ocean tides determined as solutions to the author's spherical harmonic tide theory. The lengthening of the Chandler wobble period by the pole tide is also re-computed using the author's full theory. Additionally, using the spherical harmonic theory, tidal currents and their effects on rotation are determined for available numerical and altimetric tide height models. For all models, we find that the effects of tidal currents are at least as important as those of tide height for diurnal and semi-diurnal constituents.

  7. Rare earth industries: Downstream business

    International Nuclear Information System (INIS)

    2011-01-01

    The value chain of the rare earths business involves mining, extraction, processing, refining and the manufacture of an extensive range of downstream products which find wide applications in such industries including aerospace, consumer electronics, medical, military, automotive, renewable wind and solar energy and telecommunications. In fact the entire gamut of the high-tech industries depends on a sustainable supply of rare earths elements. The explosive demand in mobile phones is an excellent illustration of the massive potential that the rare earths business offers. In a matter of less than 20 years, the number of cell phones worldwide has reached a staggering 5 billion. Soon, going by the report of their growth in sales, the world demand for cell phones may even exceed the global population. Admittedly, the rare earths business does pose certain risks. Top among the risks are the health and safety risks. The mining, extraction and refining of rare earths produce residues and wastes which carry health and safety risks. The residues from the extraction and refining are radioactive, while their effluent waste streams do pose pollution risks to the receiving rivers and waterways. But, as clearly elaborated in a recent report by IAEA experts, there are technologies and systems available to efficiently mitigate such risks. The risks are Rare Earth manageable. However, it is crucial that the risk and waste management procedures are strictly followed and adhered to. This is where effective monitoring and surveillance throughout the life of all such rare earths facilities is crucial. Fortunately, Malaysia's regulatory standards on rare earths follow international standards. In some areas, Malaysia's regulatory regime is even more stringent than the international guidelines. (author)

  8. Exercise Effects on the Course of Gray Matter Changes Over 70 Days of Bed Rest

    Science.gov (United States)

    Koppelmans, V.; Ploutz-Snyder, L.; DeDios, Y. E.; Wood, S. J.; Reuter-Lorenz, P. A.; Kofman, I.; Bloomberg, J. J.; Mulavara, A. P.; Seidler, R. D.

    2014-01-01

    Long duration spaceflight affects posture control, locomotion, and manual control. The microgravity environment is an important causal factor for spaceflight induced sensorimotor changes through direct effects on peripheral changes that result from reduced vestibular stimulation and body unloading. Effects of microgravity on sensorimotor function have been investigated on earth using bed rest studies. Long duration bed rest serves as a space-flight analogue because it mimics microgravity in body unloading and bodily fluid shifts. It has been hypothesized that the cephalad fluid shift that has been observed in microgravity could potentially affect central nervous system function and structure, and thereby indirectly affect sensorimotor or cognitive functioning. Preliminary results of one of our ongoing studies indeed showed that 70 days of long duration head down-tilt bed rest results in focal changes in gray matter volume from pre-bed rest to various time points during bed rest. These gray matter changes that could reflect fluid shifts as well as neuroplasticity were related to decrements in motor skills such as maintenance of equilibrium. In consideration of the health and performance of crewmembers both inand post-flight we are currently conducting a study that investigates the potential preventive effects of exercise on gray matter and motor performance changes that we observed over the course of bed rest. Numerous studies have shown beneficial effects of aerobic exercise on brain structure and cognitive performance in healthy and demented subjects over a large age range. We therefore hypothesized that an exercise intervention in bed rest could potentially mitigate or prevent the effects of bed rest on the central nervous system. Here we present preliminary outcomes of our study.

  9. A model of gettering effects of rare-earth elements in III-V compounds

    Czech Academy of Sciences Publication Activity Database

    Šrobár, Fedor; Procházková, Olga

    2006-01-01

    Roč. 100, č. 8 (2006), s. 643-- ISSN 0009-2770. [Sjezd chemických společností /58./. Ústí nad Labem, 04.09.2006-08.09.2006] R&D Projects: GA ČR(CZ) GA102/06/0153 Institutional research plan: CEZ:AV0Z20670512 Keywords : semiconductor technology * rare earth metals * getters Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.431, year: 2006

  10. Parametric resonance in neutrino oscillations in matter

    Indian Academy of Sciences (India)

    Neutrino oscillations in matter can exhibit a specific resonance enhancement - parametric resonance, which is different from the MSW resonance. Oscillations of atmospheric and solar neutrinos inside the earth can undergo parametric enhancement when neutrino trajectories cross the core of the earth. In this paper we ...

  11. New Spectral Features from Bound Dark Matter

    DEFF Research Database (Denmark)

    Catena, Riccardo; Kouvaris, Chris

    2016-01-01

    We demonstrate that dark matter particles gravitationally bound to the Earth can induce a characteristic nuclear recoil signal at low energies in direct detection experiments. The new spectral feature we predict can provide the ultimate smoking gun for dark matter discovery for experiments...... with positive signal but unclear background. The new feature is universal, in that the ratio of bound over halo dark matter event rates at detectors is independent of the dark matter-nucleon cross section....

  12. Earth tide effects on kinematic/static GPS positioning in Denmark and Greenland

    DEFF Research Database (Denmark)

    Xu, G.C.; Knudsen, Per

    2000-01-01

    A detailed Study of the Earth tide effects on the GPS kinematic/static positioning is presented in this paper by using theoretical Earth tide computation and practical GPS data processing. Tidal effects could reach up to 30 cm in Denmark and Greenland depending on the measuring time...... and the position of reference station. With a baseline less than 80 km, the difference of the Earth tide effects could reach more than 5 mm. So, in precise applications of GPS positioning, the Earth tide effect has to be taken into account even for a relative small local GPS network. Several examples are given...... for demonstrating that the Earth tide effects can be viewed by GPS surveying. They are given through static GPS data static processing, static GPS data kinematic processing, and airborne kinematic GPS data processing. In these cases, the Earth tide effects can be subtracted from the GPS results. The determination...

  13. Phenomenology of quintessino dark matter: Production of next lightest supersymmetric particles

    International Nuclear Information System (INIS)

    Bi Xiaojun; Wang Jianxiong; Zhang Chao; Zhang Xinmin

    2004-01-01

    In the model of quintessino as the dark matter particle, the dark matter and dark energy are unified in one superfield, where the dynamics of the Quintessence drives the Universe acceleration and its superpartner, quintessino, makes up the dark matter of the Universe. This scenario predicts the existence of long-lived τ-tilde as the next lightest supersymmetric particle. In this paper we study the possibility of detecting τ-tilde produced by the high energy cosmic neutrinos interacting with the earth matter. By a detailed calculation we find that the event rate is one to several hundred per year at a detector with an effective area of 1 km 2 . The study in this paper can be also applied to models of gravitino or axino dark matter particles

  14. Evidence of dark matter from biological observations

    International Nuclear Information System (INIS)

    Zioutas, K.

    1990-01-01

    In accordance with the generally accepted properties of dark matter (DM) candidates, the probability of their interaction with living matter must be equal to that for inorganic matter, and the expected effects might be unique and provide the etiology related to the appearance of several biological phenomena having sometimes fatal late effects. Although collisions with DM are rare, the charged secondaries (recoiling atoms) are expected to be high linear energy transfer particles favouring the highest relative biological effectiveness values for this, as yet invisible, part of the natural background radiation. A few cases are given, where a correlation between DM interaction and phenomena in living matter might already exist, or can show up in existing data: biorhythms with periodicities identical to known cosmic frequencies are explainable with gravitationally clustered DM around the sun, the moon, the earth, etc. The observed arrhythmia, when biological probes are moved (in airplanes, satellites, etc.) support this idea strongly. It is also proposed to implement some of the biological properties and processes (such as element composition and chemical reactions) in future DM detectors in order to improve their sensitivity. The interdisciplinary feedback is bidirectional: huge DM detectors could be used in attempt to understand enigmatic biological behaviour. (orig.)

  15. The Runaway Greenhouse Effect on Earth and other Planets

    Science.gov (United States)

    Rabbette, Maura; Pilewskie, Peter; McKay, Christopher; Young, Robert

    2001-01-01

    Water vapor is an efficient absorber of outgoing longwave infrared radiation on Earth and is the primary greenhouse gas. Since evaporation increases with increasing sea surface temperature, and the increase in water vapor further increases greenhouse warming, there is a positive feedback. The runaway greenhouse effect occurs if this feedback continues unchecked until all the water has left the surface and enters the atmosphere. For Mars and the Earth the runaway greenhouse was halted when water vapor became saturated with respect to ice or liquid water respectively. However, Venus is considered to be an example of a planet where the runaway greenhouse effect did occur, and it has been speculated that if the solar luminosity were to increase above a certain limit, it would also occur on the Earth. Satellite data acquired during the Earth Radiation Budget Experiment (ERBE) under clear sky conditions shows that as the sea surface temperature (SST) increases, the rate of outgoing infrared radiation at the top of the atmosphere also increases, as expected. Over the pacific warm pool where the SST exceeds 300 K the outgoing radiation emitted to space actually decreases with increasing SST, leading to a potentially unstable system. This behavior is a signature of the runaway greenhouse effect on Earth. However, the SST never exceeds 303K, thus the system has a natural cap which stops the runaway. According to Stefan-Boltzmann's law the amount of heat energy radiated by the Earth's surface is proportional to (T(sup 4)). However, if the planet has a substantial atmosphere, it can absorb all infrared radiation from the lower surface before the radiation penetrates into outer space. Thus, an instrument in space looking at the planet does not detect radiation from the surface. The radiation it sees comes from some level higher up. For the earth#s atmosphere the effective temperature (T(sub e)) has a value of 255 K corresponding to the middle troposphere, above most of the

  16. Macro Dark Matter

    CERN Document Server

    Jacobs, David M; Lynn, Bryan W.

    2015-01-01

    Dark matter is a vital component of the current best model of our universe, $\\Lambda$CDM. There are leading candidates for what the dark matter could be (e.g. weakly-interacting massive particles, or axions), but no compelling observational or experimental evidence exists to support these particular candidates, nor any beyond-the-Standard-Model physics that might produce such candidates. This suggests that other dark matter candidates, including ones that might arise in the Standard Model, should receive increased attention. Here we consider a general class of dark matter candidates with characteristic masses and interaction cross-sections characterized in units of grams and cm$^2$, respectively -- we therefore dub these macroscopic objects as Macros. Such dark matter candidates could potentially be assembled out of Standard Model particles (quarks and leptons) in the early universe. A combination of earth-based, astrophysical, and cosmological observations constrain a portion of the Macro parameter space; ho...

  17. Simulation of the effects of rare earth elements presence in the growth of III-V compound layers

    Czech Academy of Sciences Publication Activity Database

    Šrobár, Fedor; Procházková, Olga

    2007-01-01

    Roč. 1, č. 10 (2007), s. 528-530 ISSN 1842-6573 R&D Projects: GA ČR GA102/06/0153 Institutional research plan: CEZ:AV0Z20670512 Keywords : semiconductor technology * rare earth compounds * getters Subject RIV: BM - Solid Matter Physics ; Magnetism

  18. Influence of management on the composition of organic matter in a red-brown earth as shown by 13C nuclear magnetic resonance

    International Nuclear Information System (INIS)

    Oades, J.M.; Waters, A.G.; Jones, G.P.; Vassallo, A.M.; Wilson, M.A.

    1988-01-01

    Samples were obtained from the same red-brown earth: in an undisturbed state, after 60 years of an exploitive wheat-fallow rotation and after 40 years under a fertilized mixed grass-legume pasture. Organic materials were concentrated in various fractions which enabled comparative chemical composition of the organic materials in the three soils by 13 C CPMAS n.m.r. spectroscopy. Despite more than twofold differences in the organic carbon content of the soils, the chemistry of the organic matter in the soils was similar, particularly organic matter associated with clay fractions. Most of the differences detected were associated with plant debris in particles > 20 μm which contained most of the aromatic carbon. The results indicate a rapid disappearance of phenolic-carbon which originates in lignins. The composition of sodium hydroxide extracts reflects quite well the composition of the organic matter in the soil. It is concluded that in a particulate soil type, changes in amount and nature of added photosynthate do not change the composition of the organic matter which is controlled by the microbial biomass and interactions of the biomass and its decomposition products with the soil matrix. Implications of this conclusion for the turnover of organic carbon in soil and stability of soil structure are discussed. 20 refs., 4 figs

  19. Neutralino dark matter in BMSSM effective theory

    International Nuclear Information System (INIS)

    Berg, Marcus; Edsjö, Joakim; Lundström, Erik; Sjörs, Stefan; Gondolo, Paolo

    2009-01-01

    We study thermal neutralino dark matter in an effective field theory extension of the MSSM, called ''Beyond the MSSM'' (BMSSM) in Dine, Seiberg and Thomas (2007). In this class of effective field theories, the field content of the MSSM is unchanged, but the little hierarchy problem is alleviated by allowing small corrections to the Higgs/higgsino part of the Lagrangian. We perform parameter scans and compute the dark matter relic density. The light higgsino LSP scenario is modified the most; we find new regions of parameter space compared to the standard MSSM. This involves interesting interplay between the WMAP dark matter bounds and the LEP chargino bound. We also find some changes for gaugino LSPs, partly due to annihilation through a Higgs resonance, and partly due to coannihilation with light top squarks in models that are ruled in by the new effective terms

  20. Supersymmetric dark matter: Indirect detection

    International Nuclear Information System (INIS)

    Bergstroem, L.

    2000-01-01

    Dark matter detection experiments are improving to the point where they can detect or restrict the primary particle physics candidates for non baryonic dark matter. The methods for detection are usually categorized as direct, i.e., searching for signals caused by passage of dark matter particles in terrestrial detectors, or indirect. Indirect detection methods include searching for antimatter and gamma rays, in particular gamma ray lines, in cosmic rays and high-energy neutrinos from the centre of the Earth or Sun caused by accretion and annihilation of dark matter particles. A review is given of recent progress in indirect detection, both on the theoretical and experimental side

  1. Effect of sun and planet-bound dark matter on planet and satellite dynamics in the solar system

    International Nuclear Information System (INIS)

    Iorio, L.

    2010-01-01

    We apply our recent results on orbital dynamics around a mass-varying central body to the phenomenon of accretion of Dark Matter-assumed not self-annihilating-on the Sun and the major bodies of the solar system due to its motion throughout the Milky Way halo. We inspect its consequences on the orbits of the planets and their satellites over timescales of the order of the age of the solar system. It turns out that a solar Dark Matter accretion rate of ≈ 10 −12 yr −1 , inferred from the upper limit ΔM/M = 0.02−0.05 on the Sun's Dark Matter content, assumed somehow accumulated during last 4.5 Gyr, would have displaced the planets faraway by about 10 −2 −10 1 au 4.5 Gyr ago. Another consequence is that the semimajor axis of the Earth's orbit, approximately equal to the Astronomical Unit, would undergo a secular increase of 0.02-0.05 m yr −1 , in agreement with the latest observational determinations of the Astronomical Unit secular increase of 0.07±0.02 m yr −1 and 0.05 m yr −1 . By assuming that the Sun will continue to accrete Dark Matter in the next billions year at the same rate as putatively done in the past, the orbits of its planets will shrink by about 10 −1 −10 1 au ( ≈ 0.2−0.5 au for the Earth), with consequences for their fate, especially of the inner planets. On the other hand, lunar and planetary ephemerides set upper bounds on the secular variation of the Sun's gravitational parameter GM which are one one order of magnitude smaller than ≈ 10 −12 yr −1 . Dark Matter accretion on planets has, instead, less relevant consequences for their satellites. Indeed, 4.5 Gyr ago their orbits would have been just 10 −2 −10 1 km wider than now. Dark Matter accretion is not able to explain the observed accelerations of the orbits of some of the Galilean satellites of Jupiter, the secular decrease of the semimajor axis of the Earth's artificial satellite LAGEOS and the secular increase of the Moon's orbit eccentricity

  2. Effects of megascale eruptions on Earth and Mars

    Science.gov (United States)

    Thordarson, T.; Rampino, M.; Keszthelyi, L.P.; Self, S.

    2009-01-01

    Volcanic features are common on geologically active earthlike planets. Megascale or "super" eruptions involving >1000 Gt of magma have occurred on both Earth and Mars in the geologically recent past, introducing prodigious volumes of ash and volcanic gases into the atmosphere. Here we discuss felsic (explosive) and mafi c (flood lava) supereruptions and their potential atmospheric and environmental effects on both planets. On Earth, felsic supereruptions recur on average about every 100-200,000 years and our present knowledge of the 73.5 ka Toba eruption implies that such events can have the potential to be catastrophic to human civilization. A future eruption of this type may require an unprecedented response from humankind to assure the continuation of civilization as we know it. Mafi c supereruptions have resulted in atmospheric injection of volcanic gases (especially SO2) and may have played a part in punctuating the history of life on Earth. The contrast between the more sustained effects of flood basalt eruptions (decades to centuries) and the near-instantaneous effects of large impacts (months to years) is worthy of more detailed study than has been completed to date. Products of mafi c supereruptions, signifi cantly larger than known from the geologic record on Earth, are well preserved on Mars. The volatile emissions from these eruptions most likely had global dispersal, but the effects may not have been outside what Mars endures even in the absence of volcanic eruptions. This is testament to the extreme variability of the current Martian atmosphere: situations that would be considered catastrophic on Earth are the norm on Mars. ?? 2009 The Geological Society of America.

  3. Gravitational effects of condensate dark matter on compact stellar objects

    International Nuclear Information System (INIS)

    Li, X.Y.; Wang, F.Y.; Cheng, K.S.

    2012-01-01

    We study the gravitational effect of non-self-annihilating dark matter on compact stellar objects. The self-interaction of condensate dark matter can give high accretion rate of dark matter onto stars. Phase transition to condensation state takes place when the dark matter density exceeds the critical value. A compact degenerate dark matter core is developed and alter the structure and stability of the stellar objects. Condensate dark matter admixed neutron stars is studied through the two-fluid TOV equation. The existence of condensate dark matter deforms the mass-radius relation of neutron stars and lower their maximum baryonic masses and radii. The possible effects on the Gamma-ray Burst rate in high redshift are discussed

  4. Antiprotons are another matter

    International Nuclear Information System (INIS)

    Hynes, M.V.

    1987-01-01

    Theories of gravity abound, whereas experiments in gravity are few in number. An important experiment in gravity that has not been performed is the measurement of the gravitational acceleration of antimatter. Although there have been attempts to infer these properties from those of normal matter, none of these theoretical arguments are compelling. Modern theories of gravity that attempt to unify gravity with the other forces of nature predict that in principle antimatter can fall differently than normal matter in the Earth's field. Some of these supergravity theories predict that antimatter will fall faster, and that normal matter will fall with a small Baryon-number dependance in the earth's field. All of these predictions violate the Weak Equivalence Principle, a cornerstone of General Relativity, but are consistent with CPT conservation. In our approved experiment at LEAR (PS-200) we will test the Weak Equivalence Principle for antimatter by measuring the gravitational acceleration of the antiproton. Through a series of deceleration stages, antiprotons from LEAR will be lowered in energy to ∼4 Kelvin at which energy the gravitational effect will be measureable. The measurement will employ the time-of-flight technique wherein the antiprotons are released vertically in a drift tube. The spectrum of time-of-flight measurements can be used to extract the gravitational acceleration experienced by the particles. The system will be calibrated using H - ions which simulates the electromagnetic behavior of the antiproton, yet is a baryon to ∼0.1%. To extract the gravitational acceleration of the antiproton relative to the H - ion with a statistical precision of 1% will require the release of ∼10 6 to 10 7 particles

  5. Antiprotons are another matter

    International Nuclear Information System (INIS)

    Hynes, M.V.

    1988-01-01

    Theories of gravity abound whereas experiments in gravity are few in number. An important experiment in gravity that has not been performed is the measurement of the gravitational acceleration of antimatter. Although there have been attempts to infer this property from those of normal matter, none of these theoretical arguments are compelling. Modern theories of gravity that attempt to unify gravity with the other forces of nature predict that in principle antimatter can fall differently than normal matter in the Earth's field. Some of these supergravity theories predict that antimatter will fall faster and that normal matter will fall with a small Baryon-number dependence in the Earth's field. All of these predictions violate the Weak Equivalence Principle, a cornerstone of General Relativity, but are consistent with CPT conservation. In our approved experiment at LEAR (PS-200) we will test the Weak Equivalence Principle for antimatter by measuring the gravitational acceleration of the antiproton. Through a series of deceleration stages, antiprotons from LEAR will be lowered in energy to ≅ 4 Kelvin at which energy the gravitational effect will be measureable. The measurement will employ the time-of-flight technique wherein the antiprotons are released vertically in a drift tube. The spectrum of time-of-flight measurements can be used to extract the gravitational acceleration experienced by the particles. The system will be calibrated using H - ions which simulate the electromagnetic behavior of the antiproton yet are baryons to ≅ 0.1%. To extract the gravitational acceleration of the antiproton relative to the H - ion with a statistical precision of 1% will require the release of ≅ 10 6 -10 7 particles. (orig.)

  6. The MSW Effect and Matter Effects in Neutrino Oscillations

    Science.gov (United States)

    Smirnov, A. Yu.

    2006-03-01

    The MSW (Mikheyev-Smirnov-Wolfenstein) effect is the adiabatic or partially adiabatic neutrino flavor conversion in media with varying density. The main notions related to the effect, its dynamics and physical picture are reviewed. The large mixing MSW effect is realized inside the Sun providing a solution of the solar neutrino problem. The small mixing MSW effect driven by the 1-3 mixing can be realized for the supernova (SN) neutrinos. Inside collapsing stars new elements of the MSW dynamics may show up: non-oscillatory transition, non-adiabatic conversion, time dependent adiabaticity violation induced by shock waves. Effects of the resonance enhancement and the parametric enhancement of oscillations can be realized for atmospheric and accelerator neutrinos in the Earth. Precise results for neutrino oscillations in low density media with arbitrary density profile are presented and the attenuation effect is described. The area of applications is the solar and SN neutrinos inside the Earth, and the results are crucial for the neutrino oscillation tomography.

  7. Effect of mineral matter on coal self-heating rate

    Energy Technology Data Exchange (ETDEWEB)

    B. Basil Beamish; Ahmet Arisoy [University of Queensland, Brisbane, Qld. (Australia). School of Engineering

    2008-01-15

    Adiabatic self-heating tests have been conducted on subbituminous coal cores from the same seam profile, which cover a mineral matter content range of 11.2-71.1%. In all cases the heat release rate does not conform to an Arrhenius kinetic model, but can best be described by a third order polynomial. Assessment of the theoretical heat sink effect of the mineral matter in each of the tests reveals that the coal is less reactive than predicted using a simple energy conservation equation. There is an additional effect of the mineral matter in these cases that cannot be explained by heat sink alone. The disseminated mineral matter in the coal is therefore inhibiting the oxidation reaction due to physicochemical effects. 14 refs., 5 figs., 5 tabs.

  8. Exact series solution to the two flavor neutrino oscillation problem in matter

    International Nuclear Information System (INIS)

    Blennow, Mattias; Ohlsson, Tommy

    2004-01-01

    In this paper, we present a real nonlinear differential equation for the two flavor neutrino oscillation problem in matter with an arbitrary density profile. We also present an exact series solution to this nonlinear differential equation. In addition, we investigate numerically the convergence of this solution for different matter density profiles such as constant and linear profiles as well as the Preliminary Reference Earth Model describing the Earth's matter density profile. Finally, we discuss other methods used for solving the neutrino flavor evolution problem

  9. The effects of the solid inner core and nonhydrostatic structure on the earth's forced nutations and earth tides

    Science.gov (United States)

    De Vries, Dan; Wahr, John M.

    1991-01-01

    This paper computes the effects of the solid inner core (IC) on the forced nutations and earth tides, and on certain of the earth's rotational normal modes. The theoretical results are extended to include the effects of a solid IC and of nonhydrostatic structure. The presence of the IC is responsible for a new, almost diurnal, prograde normal mode which involves a relative rotation between the IC and fluid outer core about an equatorial axis. It is shown that the small size of the IC's effects on both nutations and tides is a consequence of the fact that the IC's moments of inertia are less than 1/1000 of the entire earth's.

  10. Relativistic effects on earth satellites and their measurement

    International Nuclear Information System (INIS)

    Bertotti, B.

    1988-01-01

    There are three kinds of relativistic effects on earth satellites: those due post newtonian corrections in the field of the earth; the relativistic corrections in the field of the sun; and the precession of the local frames with respect to far away bodies. The authors point out that it is not possible to eliminate the second kind by decreasing the distance of the satellite and the earth; in other words, the effect of the sun is not entirely tidal and a generalized principle of equivalence does hold exactly. Concerning the third kind, the motion of the moon and the measurements of its distance from the earth by lunar laser ranging provides a way to establish experimentally the two connections between the three fundamental frames one should consider: the local frame, determined geometrically by parallel transport; the planetary dynamical frame; and the kinematical frame defined by extragalactic radio sources. According to general relativity the first two frames are related by de Sitter's precision; the last two coincide. It shown that the connections between the first two frames and the first and third frame are already hidden in the existing data

  11. Long time-scale fluctuations in the evolution of the Earth

    International Nuclear Information System (INIS)

    McCrea, W.H.

    1981-01-01

    Current knowledge about certain terrestrial phenomena is reviewed: (a) to discover the extent to which the behaviour of the Earth may be influenced by fluctuations in its astronomical environment and (b) to see if new knowledge of that environment may be gained from its influence on the Earth. Fluctuations in geomagnetism, climate, glaciation, biological extinctions etc. are surveyed with special regard to datings and characteristic time-intervals; correlations between such fluctuations are discussed. Astronomical phenomena, within the Solar System and elsewhere in the Galaxy, that might cause terrestrial effects are reviewed. Fluctuations of glaciation within an ice-epoch may result from changes of insolation accompanying fluctuations of the Earth's motion relative to the Sun. Some evidence suggests that an ice-epoch may be triggered by variations of the astronomical environment encountered in the Sun's motion relative to the Galaxy; but tectonic changes on Earth may be the main trigger. Impacts of planetesimals may be more important than hitherto recognized. Although the intensity of solar 'activity' is variable, terrestrial effects provide no confirmation that the Sun is a 'variable star'. As for the Galaxy, impacting planetesimals may originate in interstellar clouds, and so provide on Earth samples of interstellar matter. Some unsolved problems emphasized by the review are listed. (U.K.)

  12. Long time-scale fluctuations in the evolution of the Earth

    Energy Technology Data Exchange (ETDEWEB)

    McCrea, W H [Sussex Univ., Brighton (UK). Astronomy Centre

    1981-02-18

    Current knowledge about certain terrestrial phenomena is reviewed: (a) to discover the extent to which the behaviour of the Earth may be influenced by fluctuations in its astronomical environment and (b) to see if new knowledge of that environment may be gained from its influence on the Earth. Fluctuations in geomagnetism, climate, glaciation, biological extinctions etc. are surveyed with special regard to datings and characteristic time-intervals; correlations between such fluctuations are discussed. Astronomical phenomena, within the Solar System and elsewhere in the Galaxy, that might cause terrestrial effects are reviewed. Fluctuations of glaciation within an ice-epoch may result from changes of insolation accompanying fluctuations of the Earth's motion relative to the Sun. Some evidence suggests that an ice-epoch may be triggered by variations of the astronomical environment encountered in the Sun's motion relative to the Galaxy; but tectonic changes on Earth may be the main trigger. Impacts of planetesimals may be more important than hitherto recognized. Although the intensity of solar 'activity' is variable, terrestrial effects provide no confirmation that the Sun is a 'variable star'. As for the Galaxy, impacting planetesimals may originate in interstellar clouds, and so provide on Earth samples of interstellar matter. Some unsolved problems emphasized by the review are listed.

  13. Capturing prokaryotic dark matter genomes.

    Science.gov (United States)

    Gasc, Cyrielle; Ribière, Céline; Parisot, Nicolas; Beugnot, Réjane; Defois, Clémence; Petit-Biderre, Corinne; Boucher, Delphine; Peyretaillade, Eric; Peyret, Pierre

    2015-12-01

    Prokaryotes are the most diverse and abundant cellular life forms on Earth. Most of them, identified by indirect molecular approaches, belong to microbial dark matter. The advent of metagenomic and single-cell genomic approaches has highlighted the metabolic capabilities of numerous members of this dark matter through genome reconstruction. Thus, linking functions back to the species has revolutionized our understanding of how ecosystem function is sustained by the microbial world. This review will present discoveries acquired through the illumination of prokaryotic dark matter genomes by these innovative approaches. Copyright © 2015 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  14. Doppler effect on indirect detection of dark matter using dark matter only simulations

    Science.gov (United States)

    Powell, Devon; Laha, Ranjan; Ng, Kenny C. Y.; Abel, Tom

    2017-03-01

    Indirect detection of dark matter is a major avenue for discovery. However, baryonic backgrounds are diverse enough to mimic many possible signatures of dark matter. In this work, we study the newly proposed technique of dark matter velocity spectroscopy [E. G. Speckhard, K. C. Y. Ng, J. F. Beacom, and R. Laha, Phys. Rev. Lett. 116, 031301 (2016), 10.1103/PhysRevLett.116.031301]. The nonrotating dark matter halo and the Solar motion produce a distinct longitudinal dependence of the signal which is opposite in direction to that produced by baryons. Using collisionless dark matter only simulations of Milky Way like halos, we show that this new signature is robust and holds great promise. We develop mock observations by a high energy resolution x-ray spectrometer on a sounding rocket, the Micro-X experiment, to our test case, the 3.5 keV line. We show that by using six different pointings, Micro-X can exclude a constant line energy over various longitudes at ≥3 σ . The halo triaxiality is an important effect, and it will typically reduce the significance of this signal. We emphasize that this new smoking gun in motion signature of dark matter is general and is applicable to any dark matter candidate which produces a sharp photon feature in annihilation or decay.

  15. Study of Neutrino-Induced Neutrons in Dark Matter Detectors for Supernova Burst Neutrinos

    Science.gov (United States)

    Kwan, Newton; Scholberg, Kate

    2017-09-01

    When supernova burst neutrinos (1-50 MeV) pass through the Earth, they occasionally interact with the passive shielding surrounding dark matter detectors. When the neutrinos interact, one or two roughly 2 MeV neutrons are scattered isotropically and uniformly, often leaving undetected. Occasionally, these neutrino-induced neutrons (NINs) interact with the detector and leave a background signal similar to a WIMP. The purpose of this study is to understand the effects of NINs on active dark matter detectors during a supernova burst.

  16. Life from the stars?. [extraterrestrial sources contributing to chemical evolution on Earth

    Science.gov (United States)

    Pendleton, Yvonne J.; Cruikshank, Dale P.

    1994-01-01

    Scientists are now seriously considering the possibility that organic matter from interstellar space could have influenced, or even spurred, the origin of life on Earth. Various aspects of chemical evolution are discussed along with possible extraterrestrial sources responsible for contributing to Earth's life-producing, chemical composition. Specific topics covered include the following: interstellar matter, molecular clouds, asteroid dust, organic molecules in our solar system, interplanetary dust and comets, meteoritic composition, and organic-rich solar-system bodies.

  17. Self-Destructing Dark Matter

    Energy Technology Data Exchange (ETDEWEB)

    Grossman, Yuval [Cornell U., LEPP; Harnik, Roni [Fermilab; Telem, Ofri [Cornell U., LEPP; Zhang, Yue [Northwestern U.

    2017-12-01

    We present Self-Destructing Dark Matter (SDDM), a new class of dark matter models which are detectable in large neutrino detectors. In this class of models, a component of dark matter can transition from a long-lived state to a short-lived one by scattering off of a nucleus or an electron in the Earth. The short-lived state then decays to Standard Model particles, generating a dark matter signal with a visible energy of order the dark matter mass rather than just its recoil. This leads to striking signals in large detectors with high energy thresholds. We present a few examples of models which exhibit self destruction, all inspired by bound state dynamics in the Standard Model. The models under consideration exhibit a rich phenomenology, possibly featuring events with one, two, or even three lepton pairs, each with a fixed invariant mass and a fixed energy, as well as non-trivial directional distributions. This motivates dedicated searches for dark matter in large underground detectors such as Super-K, Borexino, SNO+, and DUNE.

  18. Can modified gravity from extra dimensions explain dark matter effects?

    International Nuclear Information System (INIS)

    Kar, S.; Bharadwaj, S.; Pal, S.

    2006-01-01

    Observations on galaxy rotation curves and X-ray profiles of galaxy clusters over several decades have shown us that there exists a need for non-luminous (dark) matter. Cosmological observations also point towards the existence of dark components of two kinds - dark matter and dark energy - which, together, seem to be most of what is there the universe. However, for several years, there has been a line of thought which proposes modified gravity as an alternative to dark matter. In this article, we show, how the effective Einstein equations which arise in the context of the currently fashionable warped braneworld models, can explain the effects of dark matter as a manifestation of the consequences of the existence of extra dimensions. Finally, in order to distinguish between the effects of material dark matter and modified gravity, we calculate gravitational lensing in our modified gravity theory and show distinct differences in the deflection angles. If confirmed with observations, our results may shed new light on the existence of extra dimensions and dark matter. (authors)

  19. Ultrasonic attenuation in rare-earth monoarsenides

    Indian Academy of Sciences (India)

    2015-11-27

    Home; Journals; Pramana – Journal of Physics; Volume 86; Issue 6. Ultrasonic attenuation in rare-earth monoarsenides .... Proceedings of the International Workshop/Conference on Computational Condensed Matter Physics and Materials Science (IWCCMP-2015). Posted on November 27, 2015. Guest Editors: Anurag ...

  20. Mixed alkaline earth effect in sodium aluminosilicate glasses

    DEFF Research Database (Denmark)

    Kjeldsen, Jonas; Smedskjær, Morten Mattrup; Mauro, John C.

    2013-01-01

    While the mixed alkali effect has received significant attention in the glass literature, the mixed alkaline earth effect has not been thoroughly studied. Here, we investigate the latter effect by partial substitution of magnesium for calcium in sodium aluminosilicate glasses. We use Raman and NMR...

  1. Hot Strange Hadronic Matter in an Effective Model

    Science.gov (United States)

    Qian, Wei-Liang; Su, Ru-Keng; Song, Hong-Qiu

    2003-10-01

    An effective model used to describe the strange hadronic matter with nucleons, Λ-hyperons, and Ξ-hyperons is extended to finite temperature. The extended model is used to study the density, temperature, and strangeness fraction dependence of the effective masses of baryons in the matter. The thermodynamical quantities, such as free energy and pressure, as well as the equation of state of the matter, are given. The project supported in part by National Natural Science Foundation of China under Grant Nos. 10075071, 10047005, 19947001, 19975010, and 10235030, and the CAS Knowledge Innovation Project No. KJCX2-N11. Also supported by the State Key Basic Research Development Program under Grant No. G200077400 and the Exploration Project of Knowledge Innovation Program of the Chinese Academy of Sciences

  2. Advances in high pressure research in condensed matter: proceedings of the international conference on condensed matter under high pressures

    International Nuclear Information System (INIS)

    Sikka, S.K.; Gupta, Satish C.; Godwal, B.K.

    1997-01-01

    The use of pressure as a thermodynamic variable for studying condensed matter has become very important in recent years. Its main effect is to reduce the volume of a substance. Thus, in some sense, it mimics the phenomena taking place during the cohesion of solids like pressure ionization, modifications in electronic properties and phase changes etc. Some of the phase changes under pressure lead to synthesis of new materials. The recent discovery of high T c superconductivity in YBa 2 Cu 3 O 7 may be indirectly attributed to the pressure effect. In applied fields like simulation of reactor accident, design of inertial confinement fusion schemes and for understanding the rock mechanical effects of shock propagation in earth due to underground nuclear explosions, the pressure versus volume relations of condensed matter are a vital input. This volume containing the proceedings of the International Conference on Condensed Matter Under High Pressure covers various aspects of high pressure pertaining to equations of state, phase transitions, electronic, optical and transport properties of solids, atomic and molecular studies, shock induced reactions, energetic materials, materials synthesis, mineral physics, geophysical and planetary sciences, biological applications and food processing and advances in experimental techniques and numerical simulations. Papers relevant to INIS are indexed separately

  3. The search for dark matter

    International Nuclear Information System (INIS)

    Smith, Nigel; Spooner, Neil

    2000-01-01

    Experiments housed deep underground are searching for new particles that could simultaneously solve one of the biggest mysteries in astrophysics and reveal what lies beyond the Standard Model of particle physics. Physicists are very particular about balancing budgets. Energy, charge and momentum all have to be conserved and often money as well. Astronomers were therefore surprised and disturbed to learn in the 1930s that our own Milky Way galaxy behaved as if it contained more matter than could be seen with telescopes. This puzzling non-luminous matter became known as ''dark matter'' and we now know that over 90% of the matter in the entire universe is dark. In later decades the search for this dark matter shifted from the heavens to the Earth. In fact, the search for dark matter went underground. Today there are experiments searching for dark matter hundreds and thousands of metres below ground in mines, road tunnels and other subterranean locations. These experiments are becoming more sensitive every year and are beginning to test various new models and theories in particle physics and cosmology. (UK)

  4. Detection of Supernova Neutrinos on the Earth for Large θ13

    Science.gov (United States)

    Xu, Jing; Huang, Ming-Yang; Hu, Li-Jun; Guo, Xin-Heng; Young, Bing-Lin

    2014-02-01

    Supernova (SN) neutrinos detected on the Earth are subject to the shock wave effects, the Mikheyev—Smirnov—Wolfenstein (MSW) effects, the neutrino collective effects and the Earth matter effects. Considering the recent experimental result about the large mixing angle θ13 (≃ 8.8°) provided by the Daya Bay Collaboration and applying the available knowledge for the neutrino conversion probability in the high resonance region of SN, PH, which is in the form of hypergeometric function in the case of large θ13, we deduce the expression of PH taking into account the shock wave effects. It is found that PH is not zero in a certain range of time due to the shock wave effects. After considering all the four physical effects and scanning relevant parameters, we calculate the event numbers of SN neutrinos for the “Garching” distribution of neutrino energy spectrum. From the numerical results, it is found that the behaviors of neutrino event numbers detected on the Earth depend on the neutrino mass hierarchy and neutrino spectrum parameters including the dimensionless pinching parameter βα (where α refers to neutrino flavor), the average energy , and the SN neutrino luminosities Lα. Finally, we give the ranges of SN neutrino event numbers that will be detected at the Daya Bay experiment.

  5. Were Ocean Impacts an Important Mechanism to Deliver Meteoritic Organic Matter to the Early Earth? Some Inferences from Eltanin

    Science.gov (United States)

    Kyte, Frank T.; Gersonde, Rainer; Kuhn. Gerhard

    2002-01-01

    Several workers have addressed the potential for extraterrestrial delivery of volatles, including water and complex organic compounds, to the early Earth. For example, Chyba and Sagan (1992) argued that since impacts would destroy organic matter, most extraterrestrial organics must be delivered in the fine-fractions of interplanetary dust. More recent computer simulations (Pierazzo and Chyba, 1999), however, have shown that substantial amounts of amino acids may survive the impacts of large (km-sized) comets and that this may exceed the amounts derived from IDPs or Miller-Urey synthesis in the atmosphere. Once an ocean developed on the early Earth, impacts of small ,asteroids and comets into deep-ocean basins were potentially common and may have been the most likely events to deliver large amounts of organics. The deposits of the late Pliocene impact of the Eltanin asteroid into the Bellingshausen Sea provide the only record of a deep-ocean (approx. 5 km) impact that can be used to constrain models of these events. This impact was first discovered in 1981 as an Ir anomaly in sediment cores collected by the USNS Eltanin in 1965 (Kyte et al., 1981). In 1995, Polarstem expedition ANT XII/4 made the first geological survey of the suspected impact region. Three sediment cores sampled around the San Martin seamounts (approx. 57.5S, 91 W) contained well-preserved impact deposits that include disturbed ocean sediments and meteoritic impact ejecta (Gersonde et al., 1997). The latter is composed of shock- melted asteroidal materials and unmelted meteorites. In 2001, the FS Polarstem returned to the impact area during expedition ANT XVIII/5a. At least 16 cores were recovered that contain ejecta deposits. These cores and geophysical data from the expedition can be used to map the effects of the impact over a large region of the ocean floor.

  6. Role of ionizing radiation in the natural history of the Earth

    International Nuclear Information System (INIS)

    Byakov, V.M.; Stepanov, S.V.; Stepanova, O.P.

    2001-01-01

    A role of ionizing radiation in some global processes and events in geological history of the Earth is considered. In particular, we discuss: (1) the influence of ionizing radiation from radioactive nuclei disseminated in sedimentary rocks on the transformation of terrestrial organic matter into stone coals and oil; (2) the effect of cosmic rays from Supernova stars as a common cause of quasi-regular global geological processes and biocatastrophes. (author)

  7. Galactic Dark Matter and Terrestrial Periodicities

    National Research Council Canada - National Science Library

    Clube, S

    1998-01-01

    .... The Earth may thus be regarded as a probe of the disc environment; and to account for the periodicity, the Galactic disc is required to have a substantial dark matter component ( approx .15 molar mass/cu pc...

  8. Problem of simulating the Earth's induction effects in modeling polar magnetic substorms

    International Nuclear Information System (INIS)

    Mareschal, M.

    1976-01-01

    A major problem encountered in trying to model the current system associated with a polar magnetic substorm from ground-based magnetic observations is the difficulty of adequately evaluating the earth's induction effects. Two methods for simulating these effects are reviewed here. Method 1 simply reduces the earth to a perfect conductor and leads to very simple field equations. Method 2 considers the earth as a ''horizontally'' layered body of finite conductivity but requires a large amount of computational time. The performances of both methods are compared when the substorm current system can be approximated by an infinitely long electrojet flowing over a flat earth. In this case it appears that for most substorm modeling problems it is sufficient to treat the earth as a perfect conductor. The depth of this perfect conductor below the earth's surface should be selected in function of the source frequency content

  9. Reproducing the organic matter model of anthropogenic dark earth of Amazonia and testing the ecotoxicity of functionalized charcoal compounds

    Directory of Open Access Journals (Sweden)

    Carolina Rodrigues Linhares

    2012-05-01

    Full Text Available The objective of this work was to obtain organic compounds similar to the ones found in the organic matter of anthropogenic dark earth of Amazonia (ADE using a chemical functionalization procedure on activated charcoal, as well as to determine their ecotoxicity. Based on the study of the organic matter from ADE, an organic model was proposed and an attempt to reproduce it was described. Activated charcoal was oxidized with the use of sodium hypochlorite at different concentrations. Nuclear magnetic resonance was performed to verify if the spectra of the obtained products were similar to the ones of humic acids from ADE. The similarity between spectra indicated that the obtained products were polycondensed aromatic structures with carboxyl groups: a soil amendment that can contribute to soil fertility and to its sustainable use. An ecotoxicological test with Daphnia similis was performed on the more soluble fraction (fulvic acids of the produced soil amendment. Aryl chloride was formed during the synthesis of the organic compounds from activated charcoal functionalization and partially removed through a purification process. However, it is probable that some aryl chloride remained in the final product, since the ecotoxicological test indicated that the chemical functionalized soil amendment is moderately toxic.

  10. Role of electroweak radiation in predictions for dark matter indirect detection

    Energy Technology Data Exchange (ETDEWEB)

    Ali Cavasonza, Leila; Pellen, Mathieu; Kraemer, Michael [RWTH Aachen, Aachen (Germany)

    2015-07-01

    A very exciting challenge in particle and astroparticle physics is the exploration of the nature of dark matter. The evidences of the existence of dark matter are also the strongest phenomenological indications for physics beyond the Standard Model. A huge experimental effort is currently made at colliders and via astrophysical experiments to shed light on the nature of dark matter: dark matter may be produced at colliders or detected through direct and indirect detection experiments. The interplay and complementarity between these different approaches offers extraordinary opportunities to improve our understanding of the nature of dark matter or to set constraints on dark matter models. In indirect detection one searches for dark matter annihilation products, that produce secondary antimatter particles like positrons and antiprotons. Such antimatter particles propagate through the Galaxy and can be detected at Earth by astrophysical experiments. Particularly interesting is the importance of electroweak corrections to the predictions for the expected fluxes at Earth. The inclusion of EW radiation from the primary dark matter annihilation products can significantly affect the spectra of the secondary SM particles. The EW radiation can be described using fragmentation functions, as done for instance in QCD. We study the quality of this approximation in a simplified SUSY model and in a UED model.

  11. Properties of Strange Matter in a Model with Effective Lagrangian

    Institute of Scientific and Technical Information of China (English)

    WANG Ping; SU Ru-Keng; SONG Hong-Qiu; ZHANG Li-Liang

    2001-01-01

    The strange hadronic matter with nucleons, A-hyperons and E-hyperons is studied by using an effective nuclear model in a mean-field approximation. The density and strangeness fraction dependence of the effective baryon masses as well as the saturation properties and stabilities of the strange hadronic matter are discussed.``

  12. Effects of primitive photosynthesis on Earth's early climate system

    Science.gov (United States)

    Ozaki, Kazumi; Tajika, Eiichi; Hong, Peng K.; Nakagawa, Yusuke; Reinhard, Christopher T.

    2018-01-01

    The evolution of different forms of photosynthetic life has profoundly altered the activity level of the biosphere, radically reshaping the composition of Earth's oceans and atmosphere over time. However, the mechanistic impacts of a primitive photosynthetic biosphere on Earth's early atmospheric chemistry and climate are poorly understood. Here, we use a global redox balance model to explore the biogeochemical and climatological effects of different forms of primitive photosynthesis. We find that a hybrid ecosystem of H2-based and Fe2+-based anoxygenic photoautotrophs—organisms that perform photosynthesis without producing oxygen—gives rise to a strong nonlinear amplification of Earth's methane (CH4) cycle, and would thus have represented a critical component of Earth's early climate system before the advent of oxygenic photosynthesis. Using a Monte Carlo approach, we find that a hybrid photosynthetic biosphere widens the range of geochemical conditions that allow for warm climate states well beyond either of these metabolic processes acting in isolation. Our results imply that the Earth's early climate was governed by a novel and poorly explored set of regulatory feedbacks linking the anoxic biosphere and the coupled H, C and Fe cycles. We suggest that similar processes should be considered when assessing the potential for sustained habitability on Earth-like planets with reducing atmospheres.

  13. Dark Matter from new Technicolor Theories

    DEFF Research Database (Denmark)

    Bjarke Gudnason, Sven; Kouvaris, Christoforos; Sannino, Francesco

    2006-01-01

    We investigate dark matter candidates emerging in recently proposed technicolor theories. We determine the relic density of the lightest, neutral, stable technibaryon having imposed weak thermal equilibrium conditions and overall electric neutrality of the Universe. In addition we consider...... sphaleron processes that violate baryon, lepton and technibaryon number. Our analysis is performed in the case of a first order electroweak phase transition as well as a second order one. We argue that, in both cases, the new technibaryon contributes to the dark matter in the Universe. Finally we examine...... the problem of the constraints on these types of dark matter components from earth based experiments....

  14. An effective equation of state for dense matter with strangeness

    International Nuclear Information System (INIS)

    Balberg, S.; Gal, A.

    1997-01-01

    An effective equation of state which generalizes the Lattimer-Swesty equation for nuclear matter is presented for matter at supernuclear densities including strange baryons. It contains an adjustable baryon potential energy density, based on models of local potentials for the baryon-baryon interactions. The features of the equation rely on the properties of nuclei for the nucleon-nucleon interactions, and mainly on experimental data from hypernuclei for the hyperon-nucleon and hyperon-hyperon interactions. The equation is used to calculate equilibrium compositions and thermodynamic properties of high density matter with strangeness in two astrophysical contexts: neutron star matter (transparent to neutrinos) and proto-neutron star matter (opaque to neutrinos). The effective equation of state reproduces typical properties of high density matter found in theoretical microscopic models. Of these, the main result is that hyperons appear in both types of matter at about twice the nuclear saturation density, and that their appearance significantly softens the equation of state. The range of maximal masses of neutron stars found in a comprehensive parameter survey is 1.4-1.7 M s un. Another typical result is that the maximal mass of a proto-neutron star with strange baryons is higher than that of an evolved neutron star (opposite to the case of nuclear matter), setting the stage for a ''delayed collapse'' scenario. (orig.)

  15. Nuclear matter from effective quark-quark interaction.

    Science.gov (United States)

    Baldo, M; Fukukawa, K

    2014-12-12

    We study neutron matter and symmetric nuclear matter with the quark-meson model for the two-nucleon interaction. The Bethe-Bruckner-Goldstone many-body theory is used to describe the correlations up to the three hole-line approximation with no extra parameters. At variance with other nonrelativistic realistic interactions, the three hole-line contribution turns out to be non-negligible and to have a substantial saturation effect. The saturation point of nuclear matter, the compressibility, the symmetry energy, and its slope are within the phenomenological constraints. Since the interaction also reproduces fairly well the properties of the three-nucleon system, these results indicate that the explicit introduction of the quark degrees of freedom within the considered constituent quark model is expected to reduce the role of three-body forces.

  16. Crash testing the largest experiment on Earth

    OpenAIRE

    Cauchi, Marija

    2015-01-01

    Under Europe lies a 27 km tunnel that is both the coldest and hottest place on Earth. The Large Hadron Collider (LHC) has already found out what gives mass to all the matter in the Universe. It is now trying to go even deeper into what makes up everything we see around us. Dr Marija Cauchi writes about her research that helped protect this atom smasher from itself. Photography by Jean Claude Vancell. http://www.um.edu.mt/think/crash-testing-the-largest-experiment-on-earth/

  17. Materials, matter and particles a brief history

    CERN Document Server

    Woolfson, Michael M

    2010-01-01

    This book traces the history of ideas about the nature of matter and also the way that mankind has used material resources that the world offers. Starting with the ideas of ancient civilizations that air, earth, fire and water were the basic ingredients of all matter, it traces the development of the science of chemistry beginning within the ranks of the alchemists. First, the idea of elements grew and then the atomic nature of matter was verified. Physicists had entered the scene, showing the nature of atoms in terms of fundamental particles and then introducing the concept of wave-particle d

  18. Dark matter and the dinosaurs the astounding interconnectedness of the universe

    CERN Document Server

    Randall, Lisa

    2015-01-01

    In this brilliant exploration of our cosmic environment, the renowned particle physicist and New York Times bestselling author of Warped Passages and Knocking on Heaven’s Door uses her research into dark matter to illuminate the startling connections between the furthest reaches of space and life here on Earth. Sixty-six million years ago, an object the size of a city descended from space to crash into Earth, creating a devastating cataclysm that killed off the dinosaurs, along with three-quarters of the other species on the planet. What was its origin? In Dark Matter and the Dinosaurs, Lisa Randall proposes it was a comet that was dislodged from its orbit as the Solar System passed through a disk of dark matter embedded in the Milky Way. In a sense, it might have been dark matter that killed the dinosaurs. Working through the background and consequences of this proposal, Randall shares with us the latest findings—established and speculative—regarding the nature and role of dark matter and the origin ...

  19. Global change-driven effects on dissolved organic matter composition: Implications for food webs of northern lakes.

    Science.gov (United States)

    Creed, Irena F; Bergström, Ann-Kristin; Trick, Charles G; Grimm, Nancy B; Hessen, Dag O; Karlsson, Jan; Kidd, Karen A; Kritzberg, Emma; McKnight, Diane M; Freeman, Erika C; Senar, Oscar E; Andersson, Agneta; Ask, Jenny; Berggren, Martin; Cherif, Mehdi; Giesler, Reiner; Hotchkiss, Erin R; Kortelainen, Pirkko; Palta, Monica M; Vrede, Tobias; Weyhenmeyer, Gesa A

    2018-03-15

    Northern ecosystems are experiencing some of the most dramatic impacts of global change on Earth. Rising temperatures, hydrological intensification, changes in atmospheric acid deposition and associated acidification recovery, and changes in vegetative cover are resulting in fundamental changes in terrestrial-aquatic biogeochemical linkages. The effects of global change are readily observed in alterations in the supply of dissolved organic matter (DOM)-the messenger between terrestrial and lake ecosystems-with potentially profound effects on the structure and function of lakes. Northern terrestrial ecosystems contain substantial stores of organic matter and filter or funnel DOM, affecting the timing and magnitude of DOM delivery to surface waters. This terrestrial DOM is processed in streams, rivers, and lakes, ultimately shifting its composition, stoichiometry, and bioavailability. Here, we explore the potential consequences of these global change-driven effects for lake food webs at northern latitudes. Notably, we provide evidence that increased allochthonous DOM supply to lakes is overwhelming increased autochthonous DOM supply that potentially results from earlier ice-out and a longer growing season. Furthermore, we assess the potential implications of this shift for the nutritional quality of autotrophs in terms of their stoichiometry, fatty acid composition, toxin production, and methylmercury concentration, and therefore, contaminant transfer through the food web. We conclude that global change in northern regions leads not only to reduced primary productivity but also to nutritionally poorer lake food webs, with discernible consequences for the trophic web to fish and humans. © 2018 John Wiley & Sons Ltd.

  20. Atmospheric neutrino oscillations for earth tomography

    International Nuclear Information System (INIS)

    Winter, Walter

    2016-01-01

    Modern proposed atmospheric neutrino oscillation experiments, such as PINGU in the Antarctic ice or ORCA in Mediterranean sea water, aim for precision measurements of the oscillation parameters including the ordering of the neutrino masses. They can, however, go far beyond that: Since neutrino oscillations are affected by the coherent forward scattering with matter, neutrinos can provide a new view on the interior of the earth. We show that the proposed atmospheric oscillation experiments can measure the lower mantle density of the earth with a precision at the level of a few percent, including the uncertainties of the oscillation parameters and correlations among different density layers. While the earth's core is, in principle, accessible by the angular resolution, new technology would be required to extract degeneracy-free information.

  1. Atmospheric Drag Effects on the Motion of an Artificial Earth Satellite

    OpenAIRE

    TAKEUCHI, Sumio; 武内, 澄夫

    1982-01-01

    Perturbative effects of atmospheric drag on the motion of an artificial earth satellite are investigated in this paper. The atmosphere is considered to rotate with the same angular velocity as the earth. The altitudes of the satellite are given with reference to the standard earth-ellipsoid. The Lagrange planetary equations in Gaussian form are applied to determine the variations of the orbital elements. The atmospheric density at the satellite is regarded as a function of time. The density f...

  2. Optimal Safety EarthingEarth Electrode Sizing Using A ...

    African Journals Online (AJOL)

    In this paper a deterministic approach in the sizing of earth electrode using the permissible touch voltage criteria is presented. The deterministic approach is effectively applied in the sizing of the length of earth rod required for the safe earthing of residential and facility buildings. This approach ensures that the earthing ...

  3. arXiv Chiral Effective Theory of Dark Matter Direct Detection

    CERN Document Server

    Bishara, Fady

    2017-02-03

    We present the effective field theory for dark matter interactions with the visible sector that is valid at scales of O(1 GeV). Starting with an effective theory describing the interactions of fermionic and scalar dark matter with quarks, gluons and photons via higher dimension operators that would arise from dimension-five and dimension-six operators above electroweak scale, we perform a nonperturbative matching onto a heavy baryon chiral perturbation theory that describes dark matter interactions with light mesons and nucleons. This is then used to obtain the coefficients of the nuclear response functions using a chiral effective theory description of nuclear forces. Our results consistently keep the leading contributions in chiral counting for each of the initial Wilson coefficients.

  4. Self-energy dispersion effects on neutron matter superfluidity

    International Nuclear Information System (INIS)

    Zuo Wei

    2001-01-01

    The effects of the dispersion and ground state correlation of the single particle self-energy on neutron matter superfluidity have been investigated in the framework of the Extended Brueckner-Hartree-Fock and the generalized BCS approaches. A sizable reduction of the energy gap is found due to the energy dependence of the self-energy. And the inclusion of the ground state correlations in the self-energy suppresses further the neutron matter superfluidity

  5. Global fits of the dark matter-nucleon effective interactions

    International Nuclear Information System (INIS)

    Catena, Riccardo; Gondolo, Paolo

    2014-01-01

    The effective theory of isoscalar dark matter-nucleon interactions mediated by heavy spin-one or spin-zero particles depends on 10 coupling constants besides the dark matter particle mass. Here we compare this 11-dimensional effective theory to current observations in a comprehensive statistical analysis of several direct detection experiments, including the recent LUX, SuperCDMS and CDMSlite results. From a multidimensional scan with about 3 million likelihood evaluations, we extract the marginalized posterior probability density functions (a Bayesian approach) and the profile likelihoods (a frequentist approach), as well as the associated credible regions and confidence levels, for each coupling constant vs dark matter mass and for each pair of coupling constants. We compare the Bayesian and frequentist approach in the light of the currently limited amount of data. We find that current direct detection data contain sufficient information to simultaneously constrain not only the familiar spin-independent and spin-dependent interactions, but also the remaining velocity and momentum dependent couplings predicted by the dark matter-nucleon effective theory. For current experiments associated with a null result, we find strong correlations between some pairs of coupling constants. For experiments that claim a signal (i.e., CoGeNT and DAMA), we find that pairs of coupling constants produce degenerate results

  6. Can extra dimensional effects allow wormholes without exotic matter?

    Energy Technology Data Exchange (ETDEWEB)

    Kar, Sayan, E-mail: sayan@iitkgp.ac.in [Department of Physics and Center for Theoretical Studies, Indian Institute of Technology, Kharagpur, 721 302 (India); Lahiri, Sayantani, E-mail: sayantani.lahiri@gmail.com [Institute for Physics, University Oldenburg, D-26111 Oldenburg (Germany); ZARM, University of Bremen, Am Fallturm, 28359 Bremen (Germany); SenGupta, Soumitra, E-mail: tpssg@iacs.res.in [Department of Theoretical Physics, Indian Association for the Cultivation of Science, 2A and 2B Raja S.C. Mallick Road, Jadavpur, Kolkata 700 032 (India)

    2015-11-12

    We explore the existence of Lorentzian wormholes in the context of an effective on-brane, scalar-tensor theory of gravity. In such theories, the timelike convergence condition, which is always violated for wormholes, has contributions, via the field equations, from on-brane matter as well as from an effective geometric stress energy generated by a bulk-induced radion field. It is shown that, for a class of wormholes, the required on-brane matter, as seen by an on-brane observer in the Jordan frame, is not exotic and does not violate the Weak Energy Condition. The presence of the effective geometric stress energy in addition to on-brane matter is largely responsible for creating this intriguing possibility. Thus, if such wormholes are ever found to exist in the Universe, they would clearly provide pointers towards the existence of a warped extra dimension as proposed in the two-brane model of Randall and Sundrum.

  7. Can extra dimensional effects allow wormholes without exotic matter?

    Directory of Open Access Journals (Sweden)

    Sayan Kar

    2015-11-01

    Full Text Available We explore the existence of Lorentzian wormholes in the context of an effective on-brane, scalar-tensor theory of gravity. In such theories, the timelike convergence condition, which is always violated for wormholes, has contributions, via the field equations, from on-brane matter as well as from an effective geometric stress energy generated by a bulk-induced radion field. It is shown that, for a class of wormholes, the required on-brane matter, as seen by an on-brane observer in the Jordan frame, is not exotic and does not violate the Weak Energy Condition. The presence of the effective geometric stress energy in addition to on-brane matter is largely responsible for creating this intriguing possibility. Thus, if such wormholes are ever found to exist in the Universe, they would clearly provide pointers towards the existence of a warped extra dimension as proposed in the two-brane model of Randall and Sundrum.

  8. A review of ionospheric effects on Earth-space propagation

    Science.gov (United States)

    Klobuchar, J. A.

    1984-01-01

    A short description is given of each ionospheric total electron content (TEC) effect upon radio waves, along with a representative value of the magnitude of each of these effects under normal ionospheric conditions. A discussion is given of the important characteristics of average ionospheric TEC behavior and the temporal and spatial variability of TEC. Radio waves undergo several effects when they pass through the Earth's ionosphere. One of the most important of these effects is a retardation, or group delay, on the modulation or information carried on the radio wave that is due to its encounter with the free, thermal electrons in the Earth's ionosphere. Other effects the ionosphere has on radio waves include: radio frequency (RF) carrier phase advance; Doppler shift of the RF carrier of the radio wave; Faraday rotation of the plane of polarization of linearly polarized waves; angular refraction or bending of the radio wave path as it travels through the ionosphere; and amplitude and phase scintillations.

  9. Measuring the Earth System in a Time of Global Environmental Change with Image Spectroscopy

    Science.gov (United States)

    Green, Robert O.

    2005-01-01

    Measuring the Earth system in a time of global environmental change. Imaging Spectroscopy enables remote measurement. Remote Measurement determination of the properties of the Earth's surface and atmosphere through the physics, chemistry and biology of the interaction of electromagnetic energy with matter.

  10. Finite temperature effects in Bose-Einstein condensed dark matter halos

    International Nuclear Information System (INIS)

    Harko, Tiberiu; Madarassy, Enikö J.M.

    2012-01-01

    Once the critical temperature of a cosmological boson gas is less than the critical temperature, a Bose-Einstein Condensation process can always take place during the cosmic history of the universe. Zero temperature condensed dark matter can be described as a non-relativistic, Newtonian gravitational condensate, whose density and pressure are related by a barotropic equation of state, with barotropic index equal to one. In the present paper we analyze the effects of the finite dark matter temperature on the properties of the dark matter halos. We formulate the basic equations describing the finite temperature condensate, representing a generalized Gross-Pitaevskii equation that takes into account the presence of the thermal cloud. The static condensate and thermal cloud in thermodynamic equilibrium is analyzed in detail, by using the Hartree-Fock-Bogoliubov and Thomas-Fermi approximations. The condensed dark matter and thermal cloud density and mass profiles at finite temperatures are explicitly obtained. Our results show that when the temperature of the condensate and of the thermal cloud are much smaller than the critical Bose-Einstein transition temperature, the zero temperature density and mass profiles give an excellent description of the dark matter halos. However, finite temperature effects may play an important role in the early stages of the cosmological evolution of the dark matter condensates

  11. Lateral Earth Pressure behind Walls Rotating about Base considering Arching Effects

    Directory of Open Access Journals (Sweden)

    Dong Li

    2014-01-01

    Full Text Available In field, the earth pressure on a retaining wall is the common effect of kinds of factors. To figure out how key factors act, it has taken into account the arching effects together with the contribution from the mode of displacement of a wall to calculate earth pressure in the proposed method. Based on Mohr circle, a conversion factor is introduced to determine the shear stresses between artificial slices in soil mass. In the light of this basis, a modified differential slices solution is presented for calculation of active earth pressure on a retaining wall. Comparisons show that the result of proposed method is identical to observations from model tests in prediction of lateral pressures for walls rotating about the base.

  12. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 126; Issue 4 ... no matter how the upper channel adjusts, the main stream shows little change, providing ... drastic bank collapse and sandbar shrinking should be urgently controlled to ...

  13. Effective Dark Matter Halo Catalog in f(R) Gravity.

    Science.gov (United States)

    He, Jian-Hua; Hawken, Adam J; Li, Baojiu; Guzzo, Luigi

    2015-08-14

    We introduce the idea of an effective dark matter halo catalog in f(R) gravity, which is built using the effective density field. Using a suite of high resolution N-body simulations, we find that the dynamical properties of halos, such as the distribution of density, velocity dispersion, specific angular momentum and spin, in the effective catalog of f(R) gravity closely mimic those in the cold dark matter model with a cosmological constant (ΛCDM). Thus, when using effective halos, an f(R) model can be viewed as a ΛCDM model. This effective catalog therefore provides a convenient way for studying the baryonic physics, the galaxy halo occupation distribution and even semianalytical galaxy formation in f(R) cosmologies.

  14. Radiophysical and geomagnetic effects of rocket burn and launch in the near-the-earth environment

    CERN Document Server

    Chernogor, Leonid F

    2013-01-01

    Radiophysical and Geomagnetic Effects of Rocket Burn and Launch in the Near-the-Earth Environment describes experimental and theoretical studies on the effects of rocket burns and launchings on the near-the-Earth environment and geomagnetic fields. It illuminates the main geophysical and radiophysical effects on the ionosphere and magnetosphere surrounding the Earth that accompany rocket or cosmic apparatus burns and launchings from 1,000 to 10,000 kilometers.The book analyzes the disturbances of plasma and the ambient magnetic and electric fields in the near-Earth environment from rocket burn

  15. Separating the effects of organic matter-mineral interactions and organic matter chemistry on the sorption of diuron and phenanthrene.

    Science.gov (United States)

    Ahangar, Ahmad Gholamalizadeh; Smernik, Ronald J; Kookana, Rai S; Chittleborough, David J

    2008-06-01

    Even though it is well established that soil C content is the primary determinant of the sorption affinity of soils for non-ionic compounds, it is also clear that organic carbon-normalized sorption coefficients (K(OC)) vary considerably between soils. Two factors that may contribute to K(OC) variability are variations in organic matter chemistry between soils and interactions between organic matter and soil minerals. Here, we quantify these effects for two non-ionic sorbates-diuron and phenanthrene. The effect of organic matter-mineral interactions were evaluated by comparing K(OC) for demineralized (HF-treated) soils, with K(OC) for the corresponding whole soils. For diuron and phenanthrene, average ratios of K(OC) of the HF-treated soils to K(OC) of the whole soils were 2.5 and 2.3, respectively, indicating a substantial depression of K(OC) due to the presence of minerals in the whole soils. The effect of organic matter chemistry was determined by correlating K(OC) against distributions of C types determined using solid-state (13)C NMR spectroscopy. For diuron, K(OC) was positively correlated with aryl C and negatively correlated with O-alkyl C, for both whole and HF-treated soils, whereas for phenanthrene, these correlations were only present for the HF-treated soils. We suggest that the lack of a clear effect of organic matter chemistry on whole soil K(OC) for phenanthrene is due to an over-riding influence of organic matter-mineral interactions in this case. This hypothesis is supported by a correlation between the increase in K(OC) on HF-treatment and the soil clay content for phenanthrene, but not for diuron.

  16. Effect of CP violation in the singlet-doublet dark matter model

    Directory of Open Access Journals (Sweden)

    Tomohiro Abe

    2017-08-01

    Full Text Available We revisit the singlet-doublet dark matter model with a special emphasis on the effect of CP violation on the dark matter phenomenology. The CP violation in the dark sector induces a pseudoscalar interaction of a fermionic dark matter candidate with the SM Higgs boson. The pseudoscalar interaction helps the dark matter candidate evade the strong constraints from the dark matter direct detection experiments. We show that the model can explain the measured value of the dark matter density even if dark matter direct detection experiments do not observe any signal. We also show that the electron electric dipole moment is an important complement to the direct detection for testing this model. Its value is smaller than the current upper bound but within the reach of future experiments.

  17. A Search for Weakly Interacting Particles with the Cryogenic Dark Matter Search Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bruch, Tobias [Univ. of Zurich (Switzerland)

    2010-01-01

    Dark matter particles cannot only be detected directly in laboratories, but also indirectly by their annihilation products. Previous predictions of the neutrino flux from WIMP annihilation in the Earth and the Sun have assumed that galactic dark matter is distributed according to the SHM. Although the dark disc has a local density comparable to the dark halo, its higher phase space density at low velocities greatly enhances capture rates in the Sun and Earth. For typical dark disc properties, the resulting muon flux from the Earth is increased by three orders of magnitude over the SHM, while for the Sun the increase is one order of magnitude. This significantly increases the prospects of neutrino telescopes to fix or constrain parameters in WIMP models. The flux from the Earth is extremely sensitive to the detailed properties of the dark disc, while the flux from the Sun is more robust.

  18. Spinning Earth and its Coriolis effect on the circuital light beams ...

    Indian Academy of Sciences (India)

    2016-10-06

    Oct 6, 2016 ... spinning motion between ether and Earth at and near its surface and has reached the well-known formula of. Sagnac effect for the circuital opposing light beams on the surface of the spinning Earth as given above. But unfortunately, the same formula arises in the case of electromagnetic fields (originating ...

  19. An Overview of Rare Earth Science and Technology

    Science.gov (United States)

    Gschneidner, Karl, Jr.

    2012-02-01

    Currently rare earth science and technology is robust: this includes all the major branches of science -- biochemistry, chemistry, materials and physics. There are, however, currently some anomalies and distortions especially in the technology and applications sector of the rare earth field, which is caused by the dominance of China on the sales of rare earths and rare earth containing products. For the past 5 to 10 years ˜95% of rare earths utilized in commerce came from China. Although Chinese actions have lead to sudden and large price spikes and export embargoes, the rare earths are still available but at a higher cost. The start up of production in 2011 at mines in the USA and Australia will alleviate this situation in about two years. Basic and applied research on the condensed matter physics/materials science has hardly been impacted by these events, but new research opportunities are opening up especially with regard to the USA's military and energy security. Magnets seems to be the hottest topic, but research on battery materials, phosphors and catalysts are also (or should be) strongly considered.

  20. Mirror matter as self-interacting dark matter

    International Nuclear Information System (INIS)

    Mohapatra, R.N.; Nussinov, S.; Teplitz, V.L.

    2002-01-01

    It has been argued that the observed core density profile of galaxies is inconsistent with having a dark matter particle that is collisionless and that alternative dark matter candidates which are self-interacting may explain observations better. One new class of self-interacting dark matter that has been proposed in the context of mirror universe models of particle physics is the mirror hydrogen atom, whose stability is guaranteed by the conservation of mirror baryon number. We show that the effective transport cross section for mirror hydrogen atoms has the right order of magnitude for solving the 'cuspy' halo problem. Furthermore, the suppression of dissipation effects for mirror atoms due to a higher mirror mass scale prevents the mirror halo matter from collapsing into a disk, strengthening the argument for mirror matter as galactic dark matter

  1. Subsurface density mapping of the earth with cosmic ray muons

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Hiroyuki K.M. [Earthquake Research Institute, The University of Tokyo, 113-0032 Tokyo (Japan)

    2013-10-15

    Since its original discovery by Wilhelm Conrad Rontgen in 1895, one of the directions of researchers pursued was an application of x-ray radiography to larger objects, while the advent of high voltage x-ray tubes allowed radiographs of industrial objects to be produced in a reasonable amount of time. In spite of the great motivation we have to survey the earth's interior, we now know that x rays are not sufficiently penetrative to successfully target geophysical objects. Our current knowledge about the cross sections of the muon with matter solves the problem about this x-ray's inspectable size limit. These particles do not interact strongly with matter, and those with relativistic momentum travel long distances penetrating deep into rock. By tracking the ray paths of the muon after passing through the object, the method gives researchers the ability to study the earth in new ways. The purpose of this article is to review recent progress in probing the earth's interior with muons.

  2. The Search of Axion Dark Matter

    CERN Multimedia

    CERN. Geneva

    2006-01-01

    The axion provides a solution to the strong CP problem and is a cold dark matter candidate. I will review the limits on the axion from particle physics, stellar evolution and cosmology. The various constraints suggest that the axion mass is in the micro-eV to milli-eV range. In this range, axions contribute significantly to the energy density of the universe in the form of cold dark matter. Dark matter axions can be searched for on Earth by stimulating their conversion to microwave photons in an electromagnetic cavity permeated by a strong magnetic field. Using this technique, limits on the local halo density have been placed by the Axion Dark Matter experiment at Lawrence Livermore National Laboratory. I will give a status report on ADMX and its upgrade presently under construction. I will also discuss the results from solar axion searches (Tokyo helioscope, CAST) and laser experiments (PVLAS).

  3. The Effect of Rare Earth on the Structure and Performance of Laser Clad Coatings

    Science.gov (United States)

    Bao, Ruiliang; Yu, Huijun; Chen, Chuanzhong; Dong, Qing

    Laser cladding is one kind of advanced surface modification technology and has the abroad prospect in making the wear-resistant coating on metal substrates. However, the application of laser cladding technology does not achieve the people's expectation in the practical production because of many defects such as cracks, pores and so on. The addiction of rare earth can effectively reduce the number of cracks in the clad coating and enhance the coating wear-resistance. In the paper, the effects of rare earth on metallurgical quality, microstructure, phase structure and wear-resistance are analyzed in turns. The preliminary discussion is also carried out on the effect mechanism of rare earth. At last, the development tendency of rare earth in the laser cladding has been briefly elaborated.

  4. Rare earth elements behavior in Peruibe black mud

    International Nuclear Information System (INIS)

    Torrecilha, Jefferson K.; Carvalho, Leandro P.; Gouvea, Paulo F.M.; Silva, Paulo S.C. da

    2015-01-01

    Rare earth elements in sediments have been used as powerful tools for environmental studies because of their behavior during geochemical processes and are also widely accepted as reliable provenance tracers because they are largely water-immobile and thus behave conservatively during sedimentary processes. The Peruibe Black Mud (PBM) is a sedimentary deposit originated from the interactions of marine sediments and organic matter in an estuarine environment that originates a peloid currently used for medicinal purposes. The objective of this study was to examine rare earth elements pattern distribution in the Peruibe black mud sedimentary deposit as a proxy for its geochemical development. Elemental ratios such as LaN/YbN, Th/U and La/Th were determined and a normalization of the mean rare earth elements concentrations in the samples related to NASC indicates that the light (La to Eu) rare earth elements present values close to the unity while the heavy (Tb to Lu) rare earth elements are depleted related to NASC. It can be observed that the light rare earth elements present enrichment values slightly enriched over the unity while the heavy rare earth elements present values generally below the unity reflecting the enrichment of the light rare earth elements over the heavy rare earth. Rare earth elements concentrations determined in Peruibe black mud samples showed a distribution similar to that found in the NASC for the light rare earth elements and depleted for the heavy rare earth elements. (author)

  5. Rare earth elements behavior in Peruibe black mud

    Energy Technology Data Exchange (ETDEWEB)

    Torrecilha, Jefferson K.; Carvalho, Leandro P.; Gouvea, Paulo F.M.; Silva, Paulo S.C. da, E-mail: jeffkoy@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Rare earth elements in sediments have been used as powerful tools for environmental studies because of their behavior during geochemical processes and are also widely accepted as reliable provenance tracers because they are largely water-immobile and thus behave conservatively during sedimentary processes. The Peruibe Black Mud (PBM) is a sedimentary deposit originated from the interactions of marine sediments and organic matter in an estuarine environment that originates a peloid currently used for medicinal purposes. The objective of this study was to examine rare earth elements pattern distribution in the Peruibe black mud sedimentary deposit as a proxy for its geochemical development. Elemental ratios such as LaN/YbN, Th/U and La/Th were determined and a normalization of the mean rare earth elements concentrations in the samples related to NASC indicates that the light (La to Eu) rare earth elements present values close to the unity while the heavy (Tb to Lu) rare earth elements are depleted related to NASC. It can be observed that the light rare earth elements present enrichment values slightly enriched over the unity while the heavy rare earth elements present values generally below the unity reflecting the enrichment of the light rare earth elements over the heavy rare earth. Rare earth elements concentrations determined in Peruibe black mud samples showed a distribution similar to that found in the NASC for the light rare earth elements and depleted for the heavy rare earth elements. (author)

  6. Plasma dark matter direct detection

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, J.D.; Foot, R., E-mail: j.clarke5@pgrad.unimelb.edu.au, E-mail: rfoot@unimelb.edu.au [ARC Centre of Excellence for Particle Physics at the Terascale, School of Physics, University of Melbourne, Victoria 3010 Australia (Australia)

    2016-01-01

    Dark matter in spiral galaxies like the Milky Way may take the form of a dark plasma. Hidden sector dark matter charged under an unbroken U(1)' gauge interaction provides a simple and well defined particle physics model realising this possibility. The assumed U(1)' neutrality of the Universe then implies (at least) two oppositely charged dark matter components with self-interactions mediated via a massless 'dark photon' (the U(1)' gauge boson). In addition to nuclear recoils such dark matter can give rise to keV electron recoils in direct detection experiments. In this context, the detailed physical properties of the dark matter plasma interacting with the Earth is required. This is a complex system, which is here modelled as a fluid governed by the magnetohydrodynamic equations. These equations are numerically solved for some illustrative examples, and implications for direct detection experiments discussed. In particular, the analysis presented here leaves open the intriguing possibility that the DAMA annual modulation signal is due primarily to electron recoils (or even a combination of electron recoils and nuclear recoils). The importance of diurnal modulation (in addition to annual modulation) as a means of probing this kind of dark matter is also emphasised.

  7. Deuterium in organic matter

    International Nuclear Information System (INIS)

    Straaten, C.M. van der.

    1981-01-01

    In order to obtain an insight in the processes governing the macroclimate on earth, a knowledge is required of the behaviour of climates in the past. It is well known that D/H ratio of rain varies with temperature determined by latitude as well as by season. Because land plants use this water during the assimilation process, it is expected that the D/H variations are propagated in the organic plant matter. The D/H palaeoclimatic method has therefore been applied to peat to distinguish between the chemical constituents and trace the stable hydrogen fraction in the organic matter. The relation between the hydrogen isotopic composition of precipitation and climatic factors such as the temperature have also been studied. (Auth.)

  8. Healthy imperfect dark matter from effective theory of mimetic cosmological perturbations

    International Nuclear Information System (INIS)

    Hirano, Shin'ichi; Nishi, Sakine; Kobayashi, Tsutomu

    2017-01-01

    We study the stability of a recently proposed model of scalar-field matter called mimetic dark matter or imperfect dark matter. It has been known that mimetic matter with higher derivative terms suffers from gradient instabilities in scalar perturbations. To seek for an instability-free extension of imperfect dark matter, we develop an effective theory of cosmological perturbations subject to the constraint on the scalar field's kinetic term. This is done by using the unifying framework of general scalar-tensor theories based on the ADM formalism. We demonstrate that it is indeed possible to construct a model of imperfect dark matter which is free from ghost and gradient instabilities. As a side remark, we also show that mimetic F (R) theory is plagued with the Ostrogradsky instability.

  9. Healthy imperfect dark matter from effective theory of mimetic cosmological perturbations

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Shin' ichi; Nishi, Sakine; Kobayashi, Tsutomu, E-mail: s.hirano@rikkyo.ac.jp, E-mail: sakine@rikkyo.ac.jp, E-mail: tsutomu@rikkyo.ac.jp [Department of Physics, Rikkyo University, Toshima, Tokyo 171-8501 (Japan)

    2017-07-01

    We study the stability of a recently proposed model of scalar-field matter called mimetic dark matter or imperfect dark matter. It has been known that mimetic matter with higher derivative terms suffers from gradient instabilities in scalar perturbations. To seek for an instability-free extension of imperfect dark matter, we develop an effective theory of cosmological perturbations subject to the constraint on the scalar field's kinetic term. This is done by using the unifying framework of general scalar-tensor theories based on the ADM formalism. We demonstrate that it is indeed possible to construct a model of imperfect dark matter which is free from ghost and gradient instabilities. As a side remark, we also show that mimetic F (R) theory is plagued with the Ostrogradsky instability.

  10. Lack of gender effects on gray matter volumes in adolescent generalized anxiety disorder.

    Science.gov (United States)

    Liao, Mei; Yang, Fan; Zhang, Yan; He, Zhong; Su, Linyan; Li, Lingjiang

    2014-02-01

    Previous epidemiological and clinical studies have reported gender differences in prevalence and clinical features of generalized anxiety disorder (GAD). Such gender differences in clinical phenomenology suggest that the underlying neural circuitry of GAD could also be different in males and females. This study aimed to explore the possible gender effect on gray matter volumes in adolescents with GAD. Twenty-six adolescent GAD patients and 25 healthy controls participated and underwent high-resolution structural magnetic resonance scans. Voxel-based morphometry (VBM) was used to investigate gray matter alterations. Our study revealed a significant diagnosis main effect in the right putamen, with larger gray matter volumes in GAD patients compared to healthy controls, and a significant gender main effect in the left precuneus/posterior cingulate cortex, with larger gray matter volumes in males compared to females. No gender-by-diagnosis interaction effect was found in this study. The relatively small sample size in this study might result in a lack of power to demonstrate gender effects on brain structure in GAD. The results suggested that there are differences in gray matter volumes between males and females, but gray matter volumes in GAD are not influenced by gender. © 2013 Published by Elsevier B.V.

  11. Constraints on the near-Earth asteroid obliquity distribution from the Yarkovsky effect

    Science.gov (United States)

    Tardioli, C.; Farnocchia, D.; Rozitis, B.; Cotto-Figueroa, D.; Chesley, S. R.; Statler, T. S.; Vasile, M.

    2017-12-01

    Aims: From light curve and radar data we know the spin axis of only 43 near-Earth asteroids. In this paper we attempt to constrain the spin axis obliquity distribution of near-Earth asteroids by leveraging the Yarkovsky effect and its dependence on an asteroid's obliquity. Methods: By modeling the physical parameters driving the Yarkovsky effect, we solve an inverse problem where we test different simple parametric obliquity distributions. Each distribution results in a predicted Yarkovsky effect distribution that we compare with a χ2 test to a dataset of 125 Yarkovsky estimates. Results: We find different obliquity distributions that are statistically satisfactory. In particular, among the considered models, the best-fit solution is a quadratic function, which only depends on two parameters, favors extreme obliquities consistent with the expected outcomes from the YORP effect, has a 2:1 ratio between retrograde and direct rotators, which is in agreement with theoretical predictions, and is statistically consistent with the distribution of known spin axes of near-Earth asteroids.

  12. Effective field theory of dark matter from membrane inflationary paradigm

    Science.gov (United States)

    Choudhury, Sayantan; Dasgupta, Arnab

    2016-09-01

    In this article, we have studied the cosmological and particle physics constraints on dark matter relic abundance from effective field theory of inflation from tensor-to-scalar ratio (r), in case of Randall-Sundrum single membrane (RSII) paradigm. Using semi-analytical approach we establish a direct connection between the dark matter relic abundance (ΩDMh2) and primordial gravity waves (r), which establishes a precise connection between inflation and generation of dark matter within the framework of effective field theory in RSII membrane. Further assuming the UV completeness of the effective field theory perfectly holds good in the prescribed framework, we have explicitly shown that the membrane tension, σ ≤ O(10-9) Mp4 , bulk mass scale M5 ≤ O(0.04 - 0.05) Mp, and cosmological constant Λ˜5 ≥ - O(10-15) Mp5 , in RSII membrane plays the most significant role to establish the connection between dark matter and inflation, using which we have studied the features of various mediator mass scale suppressed effective field theory "relevant operators" induced from the localized s, t and u channel interactions in RSII membrane. Taking a completely model independent approach, we have studied an exhaustive list of tree-level Feynman diagrams for dark matter annihilation within the prescribed setup and to check the consistency of the obtained results, further we apply the constraints as obtained from recently observed Planck 2015 data and Planck + BICEP2 + Keck Array joint data sets. Using all of these derived results we have shown that to satisfy the bound on, ΩDMh2 = 0.1199 ± 0.0027, as from Planck 2015 data, it is possible to put further stringent constraint on r within, 0.01 ≤ r ≤ 0.12, for thermally averaged annihilation cross-section of dark matter, 〈 σv 〉 ≈ O(10-28 - 10-27) cm3 / s, which are very useful to constrain various membrane inflationary models.

  13. An on-line modelling study of the direct effect of atmospheric aerosols over Europe

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, L.; Baro, R.; Jimenez-Guerrero, P.

    2015-07-01

    Atmospheric aerosols affect human health, ecosystems, materials, visibility and Earths climate. Those effects are studied in this present work and depend mainly on the aerosol optical properties and how they influence the Earths radiation budget. Such properties can be divided on direct and semi-direct effect, produced by the scattering and absorption of radiation; and indirect effect, which influences the aerosols-cloud interactions. The aim of this work is to assess the direct effect through the study of the mean temperature; the radiation that reaches the Earths surface and at the top of the atmosphere; and the interaction of these meteorological variables with particulate matter (PM10). Results indicate decreases in temperature and radiation that reaches the Earth's surface, together with increases in the outgoing radiation at top of the atmosphere, and changes in the particulate matter, thus proving a colder climate due to the direct effect of atmospheric aerosols. (Author)

  14. NASA Finds Direct Proof of Dark Matter

    Science.gov (United States)

    2006-08-01

    Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies. The discovery, using NASA's Chandra X-ray Observatory and other telescopes, gives direct evidence for the existence of dark matter. "This is the most energetic cosmic event, besides the Big Bang, which we know about," said team member Maxim Markevitch of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. Lensing Illustration Gravitational Lensing Explanation These observations provide the strongest evidence yet that most of the matter in the universe is dark. Despite considerable evidence for dark matter, some scientists have proposed alternative theories for gravity where it is stronger on intergalactic scales than predicted by Newton and Einstein, removing the need for dark matter. However, such theories cannot explain the observed effects of this collision. "A universe that's dominated by dark stuff seems preposterous, so we wanted to test whether there were any basic flaws in our thinking," said Doug Clowe of the University of Arizona at Tucson, and leader of the study. "These results are direct proof that dark matter exists." Animation of Cluster Collision Animation of Cluster Collision In galaxy clusters, the normal matter, like the atoms that make up the stars, planets, and everything on Earth, is primarily in the form of hot gas and stars. The mass of the hot gas between the galaxies is far greater than the mass of the stars in all of the galaxies. This normal matter is bound in the cluster by the gravity of an even greater mass of dark matter. Without dark matter, which is invisible and can only be detected through its gravity, the fast-moving galaxies and the hot gas would quickly fly apart. The team was granted more than 100 hours on the Chandra telescope to observe the galaxy cluster 1E0657-56. The cluster is also known as the bullet cluster, because it contains a spectacular bullet-shaped cloud of hundred

  15. Effects of shading on dry matter partitioning and yield of field-grown sunflower

    International Nuclear Information System (INIS)

    Villalobos, F.J.; Soriano, A.; Fereres, E.

    1992-01-01

    Crop simulation models require quantitative descriptions of the effects of irradiance on dry matter partition and yield. The objective of this work was to quantify the effects of reduced radiation intensity during different phenological stages on the growth, dry matter partitioning and grain numbers of sunflower (Helianthus annuus, L.). A field experiment was carried out in 1990 with 50 per cent shading treatments. The earliest treatment began at crop emergence while the latest ended at first anthesis. Shading had little effect on plant leaf area growth but reduced biomass and yield. The dry matter: radiation quotient and specific leaf area increased with shading. Grain number per head was decreased by shading, with the greatest effect occurring when shading was applied prior to anthesis. All shading treatments increased dry matter partitioning to stems, decreased assimilate partitioning to the heads and had no effect on the partitioning to leaves. (author)

  16. Design of Scalable and Effective Earth Science Collaboration Tool

    Science.gov (United States)

    Maskey, M.; Ramachandran, R.; Kuo, K. S.; Lynnes, C.; Niamsuwan, N.; Chidambaram, C.

    2014-12-01

    Collaborative research is growing rapidly. Many tools including IDEs are now beginning to incorporate new collaborative features. Software engineering research has shown the effectiveness of collaborative programming and analysis. In particular, drastic reduction in software development time resulting in reduced cost has been highlighted. Recently, we have witnessed the rise of applications that allow users to share their content. Most of these applications scale such collaboration using cloud technologies. Earth science research needs to adopt collaboration technologies to reduce redundancy, cut cost, expand knowledgebase, and scale research experiments. To address these needs, we developed the Earth science collaboration workbench (CWB). CWB provides researchers with various collaboration features by augmenting their existing analysis tools to minimize learning curve. During the development of the CWB, we understood that Earth science collaboration tasks are varied and we concluded that it is not possible to design a tool that serves all collaboration purposes. We adopted a mix of synchronous and asynchronous sharing methods that can be used to perform collaboration across time and location dimensions. We have used cloud technology for scaling the collaboration. Cloud has been highly utilized and valuable tool for Earth science researchers. Among other usages, cloud is used for sharing research results, Earth science data, and virtual machine images; allowing CWB to create and maintain research environments and networks to enhance collaboration between researchers. Furthermore, collaborative versioning tool, Git, is integrated into CWB for versioning of science artifacts. In this paper, we present our experience in designing and implementing the CWB. We will also discuss the integration of collaborative code development use cases for data search and discovery using NASA DAAC and simulation of satellite observations using NASA Earth Observing System Simulation

  17. Visualizing Earth Materials

    Science.gov (United States)

    Cashman, K. V.; Rust, A.; Stibbon, E.; Harris, R.

    2016-12-01

    Earth materials are fundamental to art. They are pigments, they are clay, they provide form and color. Earth scientists, however, rarely attempt to make the physical properties of Earth materials visible through art, and similarly many artists use Earth materials without fully understanding their physical and chemical properties. Here we explore the intersection between art and science through study of the physical properties of Earth materials as characterized in the laboratory, and as transferred to paper using different techniques and suspending media. One focus of this collaboration is volcanic ash. Ash is interesting scientifically because its form provides information on the fundamental processes that drive volcanic eruptions, and determines its transport properties, and thus its potential to affect populations far downwind of the volcano. Ash properties also affect its behavior as an art material. From an aesthetic point of view, ash lends a granular surface to the image; it is also uncontrollable, and thus requires engagement between artist and medium. More fundamentally, using ash in art creates an exchange between the medium and the subject matter, and imparts something of the physical, visceral experience of volcanic landscapes to the viewer. Another component of this work uses powdered rock as a printing medium for geologic maps. Because different types of rock create powders with different properties (grain size distributions and shapes), the geology is communicated not only as color, but also by the physical characteristics of the material as it interacts with the paper. More importantly, the use of actual rocks samples as printing material for geologic maps not only makes a direct connection between the map and the material it represents, but also provides an emotional connection between the map, the viewer and the landscape, its colors, textures and geological juxtapositions. Both case studies provide examples not only of ways in which artists can

  18. Synthesis of amino acid rare earth complexes and its application in agriculture

    International Nuclear Information System (INIS)

    Luo, G.-T.; Lian, P.; Hu, Y.H.; Guo, G.-R.

    1998-01-01

    Full text: The application of rare-earth compounds in agriculture has been widely reported. So far, most rare-earth compounds used in agriculture were inorganic salt and they were difficult to be absorbed by croup. The synthesis method and structure of amino acid rare-earth complexes have been reported. In this paper, we reported the preparation of mixed amino acids rare-earth complexes and their application in agriculture. The mixed amino acids were obtained by hydrolysis of waste natural protein. Rare earth was lanthanum oxide(99%). Mixed amino acids lanthanum complexes(MALa) was prepared according to the previous method. Investigation to the effect of croup by MALa, we have make tests of citrus, rice and mung bean. The results show as follows: 1) When the experiment group citrus was sprinkled twice 400ppm MALa at bouquet stage and young fruit stage, the sugar, morose, sucrose, soluble solid matter and vitamin C of fruit were increased 21%, 20%, 22%, 22% and 6% as compared to the control group, respectively. The area of leaf and foliage branch in Spring were also increased 4.6% and 2.2%. 2) When the rice was sprinkled 300ppm MALa at early tillering stage, the productively of rice was addition to 10-15%, and the relative effect of prevention was 45.61% for sheath and culm blight of rice. 3) In the test of mungbean growth, the low consistency of MALa ( 250ppm) retain from sprouting seed. As the same time, it was similar action to seeding growth. Preliminary results indicated MLAa could used as the plant growth regulation agent on the croup. Investigation to the effect of MALa on other croup and the mechanism of biological effect on the croup are still going on

  19. Antiferromagnetic spin phase transition in nuclear matter with effective Gogny interaction

    International Nuclear Information System (INIS)

    Isayev, A.A.; Yang, J.

    2004-01-01

    The possibility of ferromagnetic and antiferromagnetic phase transitions in symmetric nuclear matter is analyzed within the framework of a Fermi liquid theory with the effective Gogny interaction. It is shown that at some critical density nuclear matter with the D1S effective force undergoes a phase transition to the antiferromagnetic spin state (opposite directions of neutron and proton spins). The self-consistent equations of spin polarized nuclear matter with the D1S force have no solutions corresponding to ferromagnetic spin ordering (the same direction of neutron and proton spins) and, hence, the ferromagnetic transition does not appear. The dependence of the antiferromagnetic spin polarization parameter as a function of density is found at zero temperature

  20. ADHESION EFFECTS WITHIN THE HARD MATTER – SOFT MATTER INTERFACE: MOLECULAR DYNAMICS

    Directory of Open Access Journals (Sweden)

    Alexey Tsukanov

    2016-12-01

    Full Text Available In the present study three soft matter – hard matter systems consisting of different nanomaterials and organic molecules were studied using the steered molecular dynamics approach in order to reveal regularities in the formation of organic-inorganic hybrids and the stability of multimolecular complexes, as well as to analyze the energy aspects of adhesion between bio-molecules and layered ceramics. The combined process free energy estimation (COPFEE procedure was used for quantitative and qualitative assessment of the considered heterogeneous systems. Interaction of anionic and cationic amino acids with the surface of a [Mg4Al2(OH122+ 2Cl–] layered double hydroxide (LDH nanosheet was considered. In both cases, strong adhesion was observed despite the opposite signs of electric charge. The free energy of the aspartic amino acid anion, which has two deprotonated carboxylic groups, was determined to be –45 kJ/mol for adsorption on the LDH surface. For the cationic arginine, with only one carboxylic group and a positive net charge, the energy of adsorption was –26 kJ/mol, which is twice higher than that of chloride anion adsorption on the same cationic nanosheet. This fact clearly demonstrates the capability of “soft matter” species to adjust themselves and fit into the surface, minimizing energy of the system. The adsorption of protonated histamine, having no carboxylic groups, on a boehmite nanosheet is also energetically favorable, but the depth of free energy well is quite small at 3.6 kJ/mol. In the adsorbed state the protonated amino-group of histamine plays the role of proton donor, while the hydroxyl oxygens of the layered hydroxide have the role of proton acceptor, which is unusual. The obtained results represent a small step towards further understanding of the adhesion effects within the hard matter – soft matter contact zone.

  1. Quark matter inside neutron stars in an effective chiral model

    International Nuclear Information System (INIS)

    Kotlorz, A.; Kutschera, M.

    1994-02-01

    An effective chiral model which describes properties of a single baryon predicts that the quark matter relevant to neutron stars, close to the deconfinement density, is in a chirally broken phase. We find the SU(2) model that pion-condensed up and down quark matter is preferred energetically at neutron star densities. It exhibits spin ordering and can posses a permanent magnetization. The equation of state of quark matter with chiral condensate is very well approximated by bag model equation of the state with suitably chosen parameters. We study quark cores inside neutron stars in this model using realistic nucleon equations of state. The biggest quark core corresponds to the second order phase transition to quark matter. Magnetic moment of the pion-condensed quark core is calculated. (author). 19 refs, 10 refs, 1 tab

  2. Prospects for direct detection of dark matter in an effective theory approach

    International Nuclear Information System (INIS)

    Catena, Riccardo

    2014-01-01

    We perform the first comprehensive analysis of the prospects for direct detection of dark matter with future ton-scale detectors in the general 11-dimensional effective theory of isoscalar dark matter-nucleon interactions mediated by a heavy spin-1 or spin-0 particle. The theory includes 8 momentum and velocity dependent dark matter-nucleon interaction operators, besides the familiar spin-independent and spin-dependent operators. From a variegated sample of 27 benchmark points selected in the parameter space of the theory, we simulate independent sets of synthetic data for ton-scale Germanium and Xenon detectors. From the synthetic data, we then extract the marginal posterior probability density functions and the profile likelihoods of the model parameters. The associated Bayesian credible regions and frequentist confidence intervals allow us to assess the prospects for direct detection of dark matter at the 27 benchmark points. First, we analyze the data assuming the knowledge of the correct dark matter nucleon-interaction type, as it is commonly done for the familiar spin-independent and spin-dependent interactions. Then, we analyze the simulations extracting the dark matter-nucleon interaction type from the data directly, in contrast to standard analyses. This second approach requires an extensive exploration of the full 11-dimensional parameter space of the dark matter-nucleon effective theory. Interestingly, we identify 5 scenarios where the dark matter mass and the dark matter-nucleon interaction type can be reconstructed from the data simultaneously. We stress the importance of extracting the dark matter nucleon-interaction type from the data directly, discussing the main challenges found addressing this complex 11-dimensional problem

  3. Characterization of extractable soil organic matter pools from African Dark Earths (AfDE): A case study in historical biochar and organic waste amendments

    Science.gov (United States)

    Fujiu, Manna; Plante, Alain; Ohno, Tsutomu; Solomon, Dawit; Lehmann, Johannes; Fraser, James; Leach, Melissa; Fairhead, James

    2014-05-01

    Anthropogenic Dark Earths are soils generated through long-term human inputs of organic and pyrogenic materials. These soils were originally discovered in the Amazon, and have since been found in Australia and in this case in Africa. African Dark Earths (AfDE) are black, highly fertile and carbon-rich soils that were formed from the original highly-weathered infertile yellowish to red Oxisols and Ultisols through an extant but hitherto overlooked climate-smart sustainable soil management system that has long been an important feature of the indigenous West African agricultural repertoire. Studies have demonstrated that ADE soils in general have significantly different organic matter properties compared to adjacent non-DE soils, largely attributable to the presence of high concentrations of ash-derived carbon. Quantification and characterization of bulk soil organic matter of several (n=11) AfDE and non-AfDE pairs of surface (0-15 cm) soils using thermal analysis techniques (TG-DSC-EGA) confirmed substantial differences in SOM composition and the presence of pyrogenic C. Such pyrogenic organic matter is generally considered recalcitrant or relatively stable, but the goal of the current study was to characterize the presumably labile, more rapidly cycling, pools of C in AfDEs through the characterization of hot water- and pyrophosphate-extractable fractions, referred to as HWEOC and PyroC respectively. Extracts were analyzed for carbon content, as well as composition using fluorescence (EEM/PARAFAC) and high resolution mass spectrometry (FTICR-MS). The amount of extractable C as a proportion of total soil C was relatively low: less than ~0.8% for HWEOC and 2.8% for PyroC. The proportion of HWEOC did not differ (P = 0.18, paired t-test) between the AfDE and the non-AfDE soils, while the proportions of PyroC were significantly larger (P = 0.001) in the AfDE soils compared to the non-AfDE soils. Preliminary analysis of the EEM/PARAFAC data suggests that AfDE samples had

  4. Quark distributions in nuclear matter and the EMC effect

    Energy Technology Data Exchange (ETDEWEB)

    Mineo, H.; Bentz, W. E-mail: bentz@keyaki.cc.u-tokai.ac.jp; Ishii, N.; Thomas, A.W.; Yazaki, K

    2004-05-03

    Quark light cone momentum distributions in nuclear matter and the structure function of a bound nucleon are investigated in the framework of the Nambu-Jona-Lasinio model. This framework describes the nucleon as a relativistic quark-diquark state, and the nuclear matter equation of state by using the mean field approximation. The scalar and vector mean fields in the nuclear medium couple to the quarks in the nucleon and their effect on the spin independent nuclear structure function is investigated in detail. Special emphasis is placed on the important effect of the vector mean field and on a formulation which guarantees the validity of the number and momentum sum rules from the outset.

  5. Antiferromagnetism of nuclear matter in the model with effective Gogny interaction

    International Nuclear Information System (INIS)

    Isayev, A.A.; Yang, J.

    2006-01-01

    The possibility of ferromagnetic (FM) antiferromagnetic (AFM) phase transitions in symmetric nuclear matter is analyzed within the framework of a Fermi-liquid theory with the effective Gogny interaction. It is shown that at some critical density nuclear matter undergoes a phase transition to the AFM spin state. The self-consistent equations of spin-polarized nuclear matter have no solutions corresponding to FM spin ordering and, hence, the FM transition does not appear. The AFM spin state properties are investigated [ru

  6. A new direction for dark matter research: intermediate-mass compact halo objects

    Energy Technology Data Exchange (ETDEWEB)

    Chapline, George F. [Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, CA (United States); Frampton, Paul H., E-mail: george.chapline@gmail.com, E-mail: paul.h.frampton@gmail.com [15 Summerheights, 29 Water Eaton Road, Oxford OX2 7PG (United Kingdom)

    2016-11-01

    The failure to find evidence for elementary particles that could serve as the constituents of dark matter brings to mind suggestions that dark matter might consist of massive compact objects (MACHOs). In particular, it has recently been argued that MACHOs with masses > 15 M {sub ⊙} may have been prolifically produced at the onset of the big bang. Although a variety of astrophysical signatures for primordial MACHOs with masses in this range have been discussed in the literature, we favor a strategy that uses the potential for magnification of stars outside our galaxy due to gravitational microlensing of these stars by MACHOs in the halo of our galaxy. We point out that the effect of the motion of the Earth on the shape of the micro-lensing brightening curves provides a promising approach to testing over the course of next several years the hypothesis that dark matter consists of massive compact objects.

  7. Modified dark matter: Relating dark energy, dark matter and baryonic matter

    Science.gov (United States)

    Edmonds, Douglas; Farrah, Duncan; Minic, Djordje; Ng, Y. Jack; Takeuchi, Tatsu

    Modified dark matter (MDM) is a phenomenological model of dark matter, inspired by gravitational thermodynamics. For an accelerating universe with positive cosmological constant (Λ), such phenomenological considerations lead to the emergence of a critical acceleration parameter related to Λ. Such a critical acceleration is an effective phenomenological manifestation of MDM, and it is found in correlations between dark matter and baryonic matter in galaxy rotation curves. The resulting MDM mass profiles, which are sensitive to Λ, are consistent with observational data at both the galactic and cluster scales. In particular, the same critical acceleration appears both in the galactic and cluster data fits based on MDM. Furthermore, using some robust qualitative arguments, MDM appears to work well on cosmological scales, even though quantitative studies are still lacking. Finally, we comment on certain nonlocal aspects of the quanta of modified dark matter, which may lead to novel nonparticle phenomenology and which may explain why, so far, dark matter detection experiments have failed to detect dark matter particles.

  8. Study of rare earth local moment magnetism and strongly correlated phenomena in various crystal structures

    Energy Technology Data Exchange (ETDEWEB)

    Kong, Tai [Iowa State Univ., Ames, IA (United States)

    2016-12-17

    Benefiting from unique properties of 4f electrons, rare earth based compounds are known for offering a versatile playground for condensed matter physics research as well as industrial applications. This thesis focuses on three specific examples that further explore the rare earth local moment magnetism and strongly correlated phenomena in various crystal structures.

  9. Preparation of Rare Earth Doped Alumina-Siloxane Gel and Its ER Effect

    Institute of Scientific and Technical Information of China (English)

    李幼荣; 张明; 周兰香; 邱关明; 井上真一; 冈本宏

    2002-01-01

    Poly(methyl methacrylate) (PMMA) was used to wrap alumina-siloxane sol through emulsion polymerization. A kind of suspensions with notable ER effect was produced by fully mixing the prepared microcapsule with silicon oil. Meanwhile a series of PMMA wrapped alumina-siloxane gel doped with rare earths was obtained and its ER effect was tested, like viscosity of different rare earth ion doped samples in different powder concentrations and at different temperatures, at the same time, leak current density and dielectric constant were measured. Results show that the ER effect of this suspension is remarkable, and its stability is much better. The condition of emulsion polymerization and the mechanism of effect are discussed.

  10. Backreaction effects on the matter side of Einstein's field equations

    CERN Document Server

    Floerchinger, Stefan; Wiedemann, Urs Achim

    2015-01-01

    Recently, we have derived a novel and compact expression for how perturbations in the matter fields of the cosmological fluid can lead to deviations from the standard Friedmann equations. Remarkably, the dissipative damping of velocity perturbations by bulk and shear viscosity in the dark sector can modify the expansion history of the universe on arbitrarily large scales. In universes in which this effect is sufficiently sizeable, it could account for the acceleration of the cosmological expansion. But even if dark matter should be less viscous and if the effect would be correspondingly smaller, it may have observable consequences in the era of precision cosmology. Here, we review the origin of this backreaction effect and possibilities to constrain it further.

  11. The Effect of Air Drag in Optimal Power-Limited Rendezvous Between Coplanar Low-Earth Orbits

    Directory of Open Access Journals (Sweden)

    Gil-Young Maeng

    1998-06-01

    Full Text Available The effect of air drag was researched when a low-earth orbit spacecraft using power-limited thruster rendezvoused another low-earth orbit spacecraft. The air density was assumed to decrease exponentially. The radius of parking orbit was 6655.935 km and that of target orbit was 7321.529 km. From the trajectories of active vehicles, the fuel consumption and the magnitude of thrust acceleration, we could conclude that the effect of air drag had to be considered in fuel optimal rendezvous problem between low-earth orbit spacecrafts. In multiple-revolution rendezvous case, the air drag was more effective.

  12. EXTRAGALACTIC DARK MATTER AND DIRECT DETECTION EXPERIMENTS

    International Nuclear Information System (INIS)

    Baushev, A. N.

    2013-01-01

    Recent astronomical data strongly suggest that a significant part of the dark matter content of the Local Group and Virgo Supercluster is not incorporated into the galaxy halos and forms diffuse components of these galaxy clusters. A portion of the particles from these components may penetrate the Milky Way and make an extragalactic contribution to the total dark matter containment of our Galaxy. We find that the particles of the diffuse component of the Local Group are apt to contribute ∼12% to the total dark matter density near Earth. The particles of the extragalactic dark matter stand out because of their high speed (∼600 km s –1 ), i.e., they are much faster than the galactic dark matter. In addition, their speed distribution is very narrow (∼20 km s –1 ). The particles have an isotropic velocity distribution (perhaps, in contrast to the galactic dark matter). The extragalactic dark matter should provide a significant contribution to the direct detection signal. If the detector is sensitive only to the fast particles (v > 450 km s –1 ), then the signal may even dominate. The density of other possible types of the extragalactic dark matter (for instance, of the diffuse component of the Virgo Supercluster) should be relatively small and comparable with the average dark matter density of the universe. However, these particles can generate anomaly high-energy collisions in direct dark matter detectors.

  13. The effective matter potential for highly relativistic neutrinos

    International Nuclear Information System (INIS)

    Konstandin, Thomas; Ohlsson, Tommy

    2006-01-01

    We investigate matter effects on highly relativistic neutrinos. The self-energy of neutrinos is determined in an electron or neutrino background taking into account resonance and finite width effects of the gauge bosons. We find minor changes compared to the formerly used formula for the propagator function and large deviations of the effective width from the decay width of the gauge bosons considering higher moments of the electron or neutrino distribution function

  14. Effect of antenatal growth and prematurity on brain white matter: diffusion tensor study

    International Nuclear Information System (INIS)

    Lepomaeki, V.; Paavilainen, T.; Komu, M.; Matomaeki, J.; Lapinleimu, H.; Liisa Lehtonen, L.; Hurme, S.; Haataja, L.; Parkkola, R.

    2012-01-01

    White matter maturation is characterised by increasing fractional anisotropy (FA) and decreasing mean diffusivity (MD). Contradictory results have been published on the effect of premature birth on white matter maturation at term-equivalent age. To assess the association of gestational age and low birth-weight-for-gestational-age (z-score) with white matter maturation. Infants (n = 76, 53 males) born at different gestational ages were imaged at term-equivalent age. Gestational age and birth weight z-score were used as continuous variables and the effect on diffusion parameters was assessed. Brain maturation was studied using regions-of-interest analysis in several white matter areas. Gestational age showed no significant effect on white matter maturation at term-equivalent age. Children with low birth weight z-score had lower FA in the genu and splenium of the corpus callosum (regression, P = 0.012 and P = 0.032; correlation, P = 0.009 and P = 0.006, respectively), and higher MD in the splenium of the corpus callosum (regression, P = 0.002; correlation, P = 0.0004) compared to children whose birth weight was appropriate for gestational age. Children with low birth weight relative to gestational age show delay and/or anomaly in white matter maturation at term-equivalent age. (orig.)

  15. Effect of antenatal growth and prematurity on brain white matter: diffusion tensor study

    Energy Technology Data Exchange (ETDEWEB)

    Lepomaeki, V. [Turku University Central Hospital, Medical Imaging Centre of Southwest Finland, Turku (Finland); Turku University Central Hospital, Turku PET-Centre, PO Box 52, Turku (Finland); Paavilainen, T.; Komu, M. [Turku University Central Hospital, Medical Imaging Centre of Southwest Finland, Turku (Finland); Matomaeki, J.; Lapinleimu, H.; Liisa Lehtonen, L. [Turku University Central Hospital and University of Turku, Department of Pediatrics, Turku (Finland); Hurme, S. [University of Turku, Department of Biostatistics, Turku (Finland); Haataja, L. [Turku University Central Hospital and University of Turku, Department of Pediatric Neurology, Turku (Finland); Parkkola, R. [Turku University Central Hospital, Medical Imaging Centre of Southwest Finland, Turku (Finland); Turku University Central Hospital, Turku PET-Centre, PO Box 52, Turku (Finland); University of Turku, Department of Diagnostic Radiology, Turku (Finland)

    2012-06-15

    White matter maturation is characterised by increasing fractional anisotropy (FA) and decreasing mean diffusivity (MD). Contradictory results have been published on the effect of premature birth on white matter maturation at term-equivalent age. To assess the association of gestational age and low birth-weight-for-gestational-age (z-score) with white matter maturation. Infants (n = 76, 53 males) born at different gestational ages were imaged at term-equivalent age. Gestational age and birth weight z-score were used as continuous variables and the effect on diffusion parameters was assessed. Brain maturation was studied using regions-of-interest analysis in several white matter areas. Gestational age showed no significant effect on white matter maturation at term-equivalent age. Children with low birth weight z-score had lower FA in the genu and splenium of the corpus callosum (regression, P = 0.012 and P = 0.032; correlation, P = 0.009 and P = 0.006, respectively), and higher MD in the splenium of the corpus callosum (regression, P = 0.002; correlation, P = 0.0004) compared to children whose birth weight was appropriate for gestational age. Children with low birth weight relative to gestational age show delay and/or anomaly in white matter maturation at term-equivalent age. (orig.)

  16. Seismic Search for Strange Quark Matter

    Science.gov (United States)

    Teplitz, Vigdor

    2004-01-01

    Two decades ago, Witten suggested that the ground state of matter might be material of nuclear density made from up, down and strange quarks. Since then, much effort has gone into exploring astrophysical and other implications of this possibility. For example, neutron stars would almost certainly be strange quark stars; dark matter might be strange quark matter. Searches for stable strange quark matter have been made in various mass ranges, with negative, but not conclusive results. Recently, we [D. Anderson, E. Herrin, V. Teplitz, and I. Tibuleac, Bull. Seis. Soc. of Am. 93, 2363 (2003)] reported a positive result for passage through the Earth of a multi-ton "nugget" of nuclear density in a search of about a million seismic reports, to the U.S. Geological Survey for the years 1990-93, not associated with known Earthquakes. I will present the evidence (timing of first signals to the 9 stations involved, first signal directions, and unique waveform characteristics) for our conclusion and discuss potential improvements that could be obtained from exploiting the seismologically quieter environments of the moon and Mars.

  17. Global effects of scalar matter production in quantum cosmology

    International Nuclear Information System (INIS)

    Barvinskij, A.O.; Ponomarev, V.N.

    1978-01-01

    Within the framework of the geometrodynamical approach global effects of the production of scalar matter filling the closed uniform Friedman Universe are considered. The physical situation is discussed, which corresponds to such a scale of space-time intervals and energies, at which the matter is essentially quantum and the quantized gravitational field is within the quasi-classical limits when its spatial inhomogeneities are small and only global quantum effects are considerable. The only dynamic variable of the gravitational field is the Friedman Universe radius. The main principles of the formalism of the canonical superspace quantization of gravitational and material fields are considered. The method shows the applicability limits of the field theory on the background of classical geometry and leads to the principally new types of interaction

  18. A quark matter contribution to the cosmic ray spectrum

    International Nuclear Information System (INIS)

    Lawson, K.

    2013-01-01

    I will describe a possible dark matter model in which the dark matter is composed of heavy nuggets of standard model quarks and antiquarks bound in a high density phase of QCD. If objects of this type are formed early in the universe's history they may provide the observed dark matter content. In this scenario the nuggets are dark not because of their fundamentally weak interactions but because of the incredibly small number density required to explain the observed mass density of the dark matter. The correspondingly small flux of these objects through the earth renders them invisible to conventional high sensitivity dark matter searches intended to detect weakly interacting particles with a flux many orders of magnitude larger. Instead the greatest search potential for dark matter models of this form may come from the largest scale cosmic ray detectors. I will briefly describe the properties of quark nugget dark matter and then use these properties in order to predict the signal they would produce in a variety of cosmic ray detectors. (authors)

  19. A systematic effective operator analysis of semi-annihilating dark matter

    International Nuclear Information System (INIS)

    Cai, Yi; Spray, Andrew

    2017-01-01

    Semi-annihilation is a generic feature of dark matter theories stabilized by symmetries larger than a ℤ 2 . It contributes to thermal freeze out, but is irrelevant for direct and collider searches. This allows semi-annihilating dark matter to avoid those limits in a natural way. We use an effective operator approach to make the first model-independent study of the associated phenomenology. We enumerate all possible operators that contribute to 2→2 semi-annihilation up to dimension 6, plus leading terms at dimension 7. We find that when the only light states charged under the dark symmetry are dark matter, the model space is highly constrained. Only fifteen operators exist, and just two for single-component dark sectors. If there can be additional light, unstable “dark partner” states the possible phenomenology greatly increases, at the cost of additional model dependence in the dark partner decay modes. We also derive the irreducible constraints on models with single-component dark matter from cosmic ray searches and astrophysical observations. We find that for semi-annihilation to electrons and light quarks, the thermal relic cross sections can be excluded for dark matter masses up to 100 GeV. However, significant model space for semi-annihilating dark matter remains.

  20. Plasma and magnetic field variations in the distant magnetotail associated with near-earth substorm effects

    Science.gov (United States)

    Baker, D. N.; Bame, S. J.; Mccomas, D. J.; Zwickl, R. D.; Slavin, J. A.; Smith, E. J.

    1987-01-01

    Examination of many individual event periods in the ISEE 3 deep-tail data set has suggested that magnetospheric substorms produce a characteristic pattern of effects in the distant magnetotail. During the growth, or tail-energy-storage phase of substorms, the magnetotail appears to grow diametrically in size, often by many earth radii. Subsequently, after the substorm expansive phase onset at earth, the distant tail undergoes a sequence of plasma, field, and energetic-particle variations as large-scale plasmoids move rapidly down the tail following their disconnection from the near-earth plasma sheet. ISEE 3 data are appropriate for the study of these effects since the spacecraft remained fixed within the nominal tail location for long periods. Using newly available auroral electrojet indices (AE and AL) and Geo particle data to time substorm onsets at earth, superposed epoch analyses of ISEE 3 and near-earth data prior to, and following, substorm expansive phase onsets have been performed. These analyses quantify and extend substantially the understanding of the deep-tail pattern of response to global substorm-induced dynamical effects.

  1. Propagation of GeV neutrinos through Earth

    Science.gov (United States)

    Olivas, Yaithd Daniel; Sahu, Sarira

    2018-06-01

    We have studied the Earth matter effect on the oscillation of upward going GeV neutrinos by taking into account the three active neutrino flavors. For neutrino energy in the range 3 to 12 GeV we observed three distinct resonant peaks for the oscillation process νe ↔νμ,τ in three distinct densities. However, according to the most realistic density profile of the Earth, the second peak at neutrino energy 6.18 GeV corresponding to the density 6.6 g/cm3 does not exist. So the resonance at this energy can not be of MSW-type. For the calculation of observed flux of these GeV neutrinos on Earth, we considered two different flux ratios at the source, the standard scenario with the flux ratio 1 : 2 : 0 and the muon damped scenario with 0 : 1 : 0. It is observed that at the detector while the standard scenario gives the observed flux ratio 1 : 1 : 1, the muon damped scenario has a different ratio. For muon damped case with Eν 20 GeV, we get the average Φνe ∼ 0 and Φνμ ≃Φντ ≃ 0.45. The upcoming PINGU will be able to shed more light on the nature of the resonance in these GeV neutrinos and hopefully will also be able to discriminate among different processes of neutrino production at the source in GeV energy range.

  2. Production and propagation of secondary particles near the earth

    International Nuclear Information System (INIS)

    Derome, L.

    2008-01-01

    A few years ago the AMS01 embarked experiment showed a particular high component of the cosmic particle flux detected below the geo-magnetic cut which was surprising because this cut represents the minimal energy that is required for cosmic radiation to reach the earth and any cosmic ray below the cut is pushed away by the earth's magnetic field. This work is based on Monte-Carlo simulations involving the generation of primary cosmic particles, their propagation in the earth magnetic field, their interaction with earth's atmosphere and the production of secondary particles. These simulations have shown that the particles below the cut are in fact particles generated in the upper part of the atmosphere, escaping from it and being trapped by the earth's magnetic field. These Monte-Carlo simulations have also been used to assess the composition of below-the-cut flux in terms of protons, electrons, positrons and light nuclei, to check the production of anti-matter in the atmosphere, and to estimate the flux of atmospheric neutrinos. (A.C.)

  3. One Health in food safety and security education: Subject matter outline for a curricular framework.

    Science.gov (United States)

    Angelos, John A; Arens, Amanda L; Johnson, Heather A; Cadriel, Jessica L; Osburn, Bennie I

    2017-06-01

    Educating students in the range of subjects encompassing food safety and security as approached from a One Health perspective requires consideration of a variety of different disciplines and the interrelationships among disciplines. The Western Institute for Food Safety and Security developed a subject matter outline to accompany a previously published One Health in food safety and security curricular framework. The subject matter covered in this outline encompasses a variety of topics and disciplines related to food safety and security including effects of food production on the environment. This subject matter outline should help guide curriculum development and education in One Health in food safety and security and provides useful information for educators, researchers, students, and public policy-makers facing the inherent challenges of maintaining and/or developing safe and secure food supplies without destroying Earth's natural resources.

  4. One Health in food safety and security education: Subject matter outline for a curricular framework

    Directory of Open Access Journals (Sweden)

    John A. Angelos

    2017-06-01

    Full Text Available Educating students in the range of subjects encompassing food safety and security as approached from a One Health perspective requires consideration of a variety of different disciplines and the interrelationships among disciplines. The Western Institute for Food Safety and Security developed a subject matter outline to accompany a previously published One Health in food safety and security curricular framework. The subject matter covered in this outline encompasses a variety of topics and disciplines related to food safety and security including effects of food production on the environment. This subject matter outline should help guide curriculum development and education in One Health in food safety and security and provides useful information for educators, researchers, students, and public policy-makers facing the inherent challenges of maintaining and/or developing safe and secure food supplies without destroying Earth's natural resources.

  5. Study of catalytic effects of mineral matter level on coal reactivity

    Energy Technology Data Exchange (ETDEWEB)

    Mazzocco, Nestor J.; Klunder, Edgar B.; Krastman, Donald

    1981-03-01

    Coal liquefaction experiments using a 400-lb/day bubble-column reactor tested the catalytic effects of added mineral matter level on coal conversion, desulfurization, and distillate yields in continuous operation under recycle conditions, with specific emphasis on the use of a disposable pyrite catalyst indigenous to the feed coal. Western Kentucky No. 11 run-of-mine (ROM) and washed coals were used as feedstocks to determine the effects of levels of mineral matter, specifically iron compounds. Liquefaction reactivity as characterized by total distillate yield was lower for washed coal, which contained less mineral matter. Liquefaction reactivity was regained when pyrite concentrate was added as a disposable catalyst to the washed coal feed in sufficient quantity to match the feed iron concentration of the run-of-mine coal liquefaction test run.

  6. Comparative study on sorption/desorption of radioeuropium on alumina, bentonite and red earth: effects of pH, ionic strength, fulvic acid, and iron oxides in red earth

    International Nuclear Information System (INIS)

    Dong Wenming; Wang Xiangke; Bian Xiaoyan; Wang Aixia; Du Jingzhou; Tao, Z.Y.

    2001-01-01

    The sorption and desorption of Eu(III) as a representative of trivalent lanthanides and actinides on bentonite, alumina, red earth and red earth treated to remove free iron oxides were comparatively investigated by using batch technique and radiotracer 152+154 Eu. The effects of pH, ionic strength, fulvic acid, iron oxides in red earth and the sorption mechanism were also discussed. As compared to alumina and red earth, Eu(III) presents a considerable distribution coefficient (K d ) onto bentonite. It was found that the pH and the presence of clay minerals are the main factors dominating the sorption/desorption characteristic of Eu 3+ in the soil, and that a sorption-desorption hysteresis on bentonite and red earth actually occurs. Furthermore, the main sorption mechanism of lanthanides onto bentonite, alumina and red earth is the formation of bridged hydroxo complexes with the surface, and there are negative effects of fulvic acid and free iron oxides in red earth on the sorption of Eu(III). The results of this paper indicate that the additivity rule on the sorption characteristic of a soil from the individual component's characteristics is not general

  7. Spectrometry of the Earth using Neutrino Oscillations

    Science.gov (United States)

    Rott, C.; Taketa, A.; Bose, D.

    2015-01-01

    The unknown constituents of the interior of our home planet have provoked the human imagination and driven scientific exploration. We herein demonstrate that large neutrino detectors could be used in the near future to significantly improve our understanding of the Earth’s inner chemical composition. Neutrinos, which are naturally produced in the atmosphere, traverse the Earth and undergo oscillations that depend on the Earth’s electron density. The Earth’s chemical composition can be determined by combining observations from large neutrino detectors with seismic measurements of the Earth’s matter density. We present a method that will allow us to perform a measurement that can distinguish between composition models of the outer core. We show that the next-generation large-volume neutrino detectors can provide sufficient sensitivity to reject extreme cases of outer core composition. In the future, dedicated instruments could be capable of distinguishing between specific Earth composition models and thereby reshape our understanding of the inner Earth in previously unimagined ways. PMID:26489447

  8. Effects of organic matter and ageing on the bioaccessibility of arsenic

    International Nuclear Information System (INIS)

    Meunier, Louise; Koch, Iris; Reimer, Kenneth J.

    2011-01-01

    Arsenic-contaminated soils may pose a risk to human health. Redevelopment of contaminated sites may involve amending soils with organic matter, which potentially increases arsenic bioaccessibility. The effects of ageing on arsenic-contaminated soils mixed with peat moss were evaluated in a simulated ageing period representing two years, during which arsenic bioaccessibility was periodically measured. Significant increases (p = 0.032) in bioaccessibility were observed for 15 of 31 samples tested, particularly in comparison with samples originally containing >30% bioaccessible arsenic in soils naturally rich in organic matter (>25%). Samples where percent arsenic bioaccessibility was unchanged with age were generally poor in organic matter (average 7.7%) and contained both arsenopyrite and pentavalent arsenic forms that remained unaffected by the organic matter amendments. Results suggest that the addition of organic matter may lead to increases in arsenic bioaccessibility, which warrants caution in the evaluation of risks associated with redevelopment of arsenic-contaminated land. - Highlights: → Adding organic matter to contaminated soils may increase arsenic bioaccessibility. → Ageing soils with >25% organic matter can lead to increased arsenic bioaccessibility. → No changes in arsenic bioaccessibility for soils poor in organic matter (mean 7.7%). → No changes in arsenic bioaccessibility for samples containing arsenopyrite. → Organic matter in soil may favour oxidation of trivalent arsenic to pentavalent form. - Adding organic carbon may increase arsenic bioaccessibility, especially in samples originally containing >30% bioaccessible arsenic in organic carbon-rich soils (>25%).

  9. Music Education and the Earth Sciences

    Science.gov (United States)

    Beauregard, J. L.

    2011-12-01

    Capturing the interest of non-science majors in science classes can be very difficult, no matter what type of science course it is. At Berklee College of Music, this challenge is especially daunting, as all students are majoring in some type of music program. To engage the Berklee students, I am trying to link the material in Earth science courses to music. The connection between Earth science and music is made in several different ways within the curriculum of each class, with the main connection via a final project. For their projects, students can use any creative outlet (or a standard presentation) to illustrate a point related to the course. Many students have chosen to compose original music and perform it for the class. Some examples of their work will be presented. These original compositions allow students to relate course material to their own lives. Additionally, since many of these students will enter professional careers in the performance and recording industries, the potential exists for them to expose large audiences to the issues of Earth sciences through music.

  10. Finite Volume Effect of Baryons in Strange Hadronic Matter

    Institute of Scientific and Technical Information of China (English)

    SUN Bao-Xi; LI Lei; NING Ping-Zhi; ZHAO En-Guang

    2001-01-01

    The finite volume effect of baryons in strange hadronic matter (SHM) is studied within the framework of relativistic mean-field theory. As this effect is concerned, the saturation density of SHM turns lower, and the binding energy per baryon decreases. Its influence to the compression modulus of SHM is also discussed.

  11. Nucleon effective masses in field theories of dense matter

    International Nuclear Information System (INIS)

    Lee, C.H.; Reddy, S.; Prakash, M.

    1998-01-01

    We point out some generic trends of effective masses in commonly used field-theoretical descriptions of stellar matter in which several species of strongly interacting particles of dissimilar masses may be present. (orig.)

  12. Nucleon effective masses in field theories of dense matter

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C H; Reddy, S; Prakash, M [Dept. of Physics and Astronomy, Stony Brook, NY (United States)

    1998-06-01

    We point out some generic trends of effective masses in commonly used field-theoretical descriptions of stellar matter in which several species of strongly interacting particles of dissimilar masses may be present. (orig.)

  13. Topological hierarchy matters — topological matters with superlattices of defects

    International Nuclear Information System (INIS)

    He Jing; Kou Su-Peng

    2016-01-01

    Topological insulators/superconductors are new states of quantum matter with metallic edge/surface states. In this paper, we review the defects effect in these topological states and study new types of topological matters — topological hierarchy matters. We find that both topological defects (quantized vortices) and non topological defects (vacancies) can induce topological mid-gap states in the topological hierarchy matters after considering the superlattice of defects. These topological mid-gap states have nontrivial topological properties, including the nonzero Chern number and the gapless edge states. Effective tight-binding models are obtained to describe the topological mid-gap states in the topological hierarchy matters. (topical review)

  14. The Effect of Improved Sub-Daily Earth Rotation Models on Global GPS Data Processing

    Science.gov (United States)

    Yoon, S.; Choi, K. K.

    2017-12-01

    Throughout the various International GNSS Service (IGS) products, strong periodic signals have been observed around the 14 day period. This signal is clearly visible in all IGS time-series such as those related to orbit ephemerides, Earth rotation parameters (ERP) and ground station coordinates. Recent studies show that errors in the sub-daily Earth rotation models are the main factors that induce such noise. Current IGS orbit processing standards adopted the IERS 2010 convention and its sub-daily Earth rotation model. Since the IERS convention had published, recent advances in the VLBI analysis have made contributions to update the sub-daily Earth rotation models. We have compared several proposed sub-daily Earth rotation models and show the effect of using those models on orbit ephemeris, Earth rotation parameters and ground station coordinates generated by the NGS global GPS data processing strategy.

  15. Earth Matters: Promoting Science Exploration through Blogs and Social Media

    Science.gov (United States)

    Ward, K.; Voiland, A. P.; Carlowicz, M. J.; Simmon, R. B.; Allen, J.; Scott, M.; Przyborski, P. D.

    2012-12-01

    NASA's Earth Observatory (EO) is a 13-year old online publication focusing on the communication of NASA Earth science research, including climate change, weather, geology, oceanography, and solar flares. We serve two primary audiences: the "attentive public"--people interested in and willing to seek out information about science, technology, and the environment--and popular media. We use the EO website (earthobservatory.nasa.gov) to host a variety of content including image-driven stories (natural events and research-based), articles featuring NASA research and, more recently, blogs that give us the ability to increase interaction with our users. For much of our site's history, our communication has been largely one way, and we have relied primarily on traditional online marketing techniques such as RSS and email listservs. As the information ecosystem evolves into one in which many users expect to play a more active role in distributing and even developing content through social media, we've experimented with various social media outlets (blogs, Twitter, Facebook, Google+, etc.) that offer new opportunities for people to interact with NASA data, scientists, and the EO editorial team. As part of our explorations, we are learning about how, and to what extent, these outlets can be used for interaction and outright promotion and how to achieve those goals with existing personnel and resources.

  16. WIMP dark matter and supersymmetry searches with neutrino telescopes

    International Nuclear Information System (INIS)

    Fornengo, N.

    2011-01-01

    The particle physics interpretation of the missing-mass, or dark-matter, a problem of cosmological and astrophysical nature, is going to be placed under strong scrutiny in the next years. From the particle physics side, accelerator physics will deeply test theoretical ideas about new physics beyond the Standard Model, where a particle physics candidate to dark matter is often naturally obtained. From the astrophysical side, many probes are already providing a great deal of independent information on signals which can be produced by the galactic or extra-galactic dark matter. The current and new-generation experimental efforts are therefore going to place under deep scrutiny the theoretical explanations of the relevant signals. The ultimate hope is in fact to be able to disentangle a dark matter signal from the various sources of backgrounds. Neutrino telescopes are one of the prominent tools for looking at dark matter and search for a signal, the neutrino flux from Earth and Sun. In this neutrino dark matter searches share properties with both direct dark matter searches and cosmic-ray indirect dark matter searches, and therefore complement these different detection techniques.

  17. Jet Definitions in Effective Field Theory and Decaying Dark Matter

    Science.gov (United States)

    Cheung, William Man Yin

    2012-06-01

    In this thesis jet production and cosmological constraints on decaying dark matter are studied. The powerful framework of effective field theory is applied in both cases to further our knowledge of particle physics. We first discuss how to apply the Soft Collinear Effective Theory (SCET) for calculating hadronic jet production rate. By applying SCET power counting, we develop a consistent approach to perform phase space integrations. This approach is then successfully applied to one-loop calculations with regard to a variety of jet algorithms. This allows us to study if the soft contribution can be factorized from the collinear ones. In particular we point out the connection between such factorization and the choice of ultraviolet regulator. We then further our study of the (exclusive) kT and C/A jet algorithms in SCET with the introduction of an additional regulator. Regularizing the virtualities and rapidities of graphs in SCET, we are able to write the next-to-leading-order dijet cross section as the product of separate hard, jet, and soft contributions. We show how to reproduce the Sudakov form factor to next-to-leading logarithmic accuracy previously calculated by the coherent branching formalism. Our resummed expression only depends on the renormalization group evolution of the hard function, rather than on that of the hard and jet functions as is usual in SCET. Finally we present a complete analysis of the cosmological constraints on decaying dark matter. For this, we have updated and extended previous analyses to include Lyman-alpha forest, large scale structure, and weak lensing observations. Astrophysical constraints are not considered in this thesis. The bounds on the lifetime of decaying dark matter are dominated by either the late-time integrated Sachs-Wolfe effect for the scenario with weak reionization, or CMB polarisation observations when there is significant reionization. For the respective scenarios, the lifetimes for decaying dark matter are

  18. Crystal field and magnetism with Wannier functions: Orthorhombic rare-earth manganites

    Czech Academy of Sciences Publication Activity Database

    Novák, Pavel; Nekvasil, Vladimír; Knížek, Karel

    358-359, MAY (2014), s. 228-232 ISSN 0304-8853 R&D Projects: GA ČR GA13-25251S Institutional support: RVO:68378271 Keywords : crystal field * rare- earth magnetism Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.970, year: 2014

  19. Near-Earth Magnetic Field Effects of Large-Scale Magnetospheric Currents

    DEFF Research Database (Denmark)

    Lühr, Hermann; Xiong, Chao; Olsen, Nils

    2017-01-01

    . Significant progress in interpreting the magnetic fields from the different sources has been achieved thanks to magnetic satellite missions like Ørsted, CHAMP and now Swarm. Of particular interest for this article is a proper representation of the magnetospheric ring current effect. Uncertainties in modelling...... its effect still produce the largest residuals between observations and present-day geomagnetic field models. A lot of progress has been achieved so far, but there are still open issues like the characteristics of the partial ring current. Other currents discussed are those flowing......Magnetospheric currents play an important role in the electrodynamics of near-Earth space. This has been the topic of many space science studies. Here we focus on the magnetic fields they cause close to Earth. Their contribution to the geomagnetic field is the second largest after the core field...

  20. An effective model for fermion dark matter. Indirect detection of supersymmetric dark matter in astronomy with the CELESTE Telescope

    International Nuclear Information System (INIS)

    Lavalle, Julien

    2004-01-01

    The purpose of this thesis is to discuss both phenomenological and experimental aspects of Dark Matter, related to its indirect detection with gamma-ray astronomy. In the MSSM framework, neutralinos arise as natural candidates to non-baryonic and Cold Dark Matter, whose gravitational effects manifest in the Universe at different scales. As they are Majorana particles, they may in principle annihilate in high density regions, as the centres of galaxies, and produce gamma rays. Nevertheless, the expected fluxes are basically low compared to experimental sensitivities. After estimating gamma fluxes from M31 and Draco galaxies in the MSSM scheme, we first generalize the MSSM couplings by studying an effective Lagrangian. We show that the only constraint of imposing a relic abundance compatible with recent measurements obviously deplete significantly the gamma ray production, but also that predictions in this effective approach are more optimistic for indirect detection than the MSSM. In a second part, we present the indirect searches for Dark Matter performed with the CELESTE Cherenkov telescope towards the galaxy M31. We propose a statistical method to reconstruct spectra, mandatory to discriminate classical and exotic spectra. The M31 data analysis enables the extraction of an upper limit on the gamma ray flux, which is the first worldwide for a galaxy in the energy range 50-500 GeV, and whose astrophysical interest goes beyond indirect searches for Dark Matter. (author)

  1. Phase transition from nuclear matter to color superconducting quark matter

    Energy Technology Data Exchange (ETDEWEB)

    Bentz, W. E-mail: bentz@keyaki.cc.u-tokai.ac.jp; Horikawa, T.; Ishii, N.; Thomas, A.W

    2003-06-02

    We construct the nuclear and quark matter equations of state at zero temperature in an effective quark theory (the Nambu-Jona-Lasinio model), and discuss the phase transition between them. The nuclear matter equation of state is based on the quark-diquark description of the single nucleon, while the quark matter equation of state includes the effects of scalar diquark condensation (color superconductivity). The effect of diquark condensation on the phase transition is discussed in detail.

  2. Value-added products from spent bleaching earth

    International Nuclear Information System (INIS)

    Loh Soh Kheang; Muzammil Ngatiman; James, Stephen

    2010-01-01

    Full text: Bleaching earth is used in the bleaching process of physical refining of palm oil to remove color, phospholipids, residue gums, oxidized products and any trace metals from the oil. These colored pigments are trapped and absorbed in the bleaching earth, thus transforming the originally whitish earth to dark grey and is, from then, named spent bleaching earth (SBE). SBE is considered as an industrial by-product as there is hardly any practical application for it. Large quantity of SBE is commonly disposed of in landfills, which poses potential hazards to environment. New economical ways in utilizing it is sought to eliminate the problem arises from its disposal. This paper presents a study on the possibility of developing a soil conditioner using enhanced SBE as the base material. The study found that there are certain attributes observed in the enhanced SBE that could be of advantages for SBE to become a good soil conditioner. The enhanced SBE contains organic matters and about 18-20 % of residue oil which exhibits good water holding capacity in slow release of water, and enriched nutrient content for plant nutrient uptake. (author)

  3. Spin-polarized neutron matter at different orders of chiral effective field theory

    OpenAIRE

    Sammarruca, F.; Machleidt, R.; Kaiser, N.

    2015-01-01

    Spin-polarized neutron matter is studied using chiral two- and three-body forces. We focus, in particular, on predictions of the energy per particle in ferromagnetic neutron matter at different orders of chiral effective field theory and for different choices of the resolution scale. We discuss the convergence pattern of the predictions and their cutoff dependence. We explore to which extent fully polarized neutron matter behaves (nearly) like a free Fermi gas. We also consider the more gener...

  4. Earth Science (A Process Approach), Section 1: The Water Cycle.

    Science.gov (United States)

    Campbell, K. C.; And Others

    Included is a collection of earth science laboratory activities, which may provide the junior or senior high school science teacher with ideas for activities in his program. The included 48 experiments are grouped into these areas: properties of matter; evaporation; atmospheric moisture and condensation; precipitation; moving water, subsurface…

  5. Searching for dark matter with neutrino telescopes

    International Nuclear Information System (INIS)

    Hooper, Dan; Silk, Joseph

    2004-01-01

    One of the most interesting mysteries of astrophysics is the puzzle of dark matter. Although numerous techniques have been explored and developed to detect this elusive substance, its nature remains unknown. One such method uses large high-energy neutrino telescopes to look for the annihilation products of dark matter annihilations. In this paper, we briefly review this technique. We describe the calculations used to find the rate of capture of WIMPs in the Sun or Earth and the spectrum of neutrinos produced in the resulting dark matter annihilations. We will discuss these calculations within the context of supersymmetry and models with universal extra dimensions, the lightest supersymmetric particle and lightest Kaluza-Klein particle providing the WIMP candidate in these cases, respectively. We will also discuss the status of some of the experiments relevant to these searches: AMANDA, IceCube and ANTARES

  6. Effects of dynamic long-period ocean tides on changes in earth's rotation rate

    Science.gov (United States)

    Nam, Young; Dickman, S. R.

    1990-01-01

    As a generalization of the zonal response coefficient first introduced by Agnew and Farrell (1978), the zonal response function kappa of the solid earth-ocean system is defined as the ratio, in the frequency domain, of the tidal change in earth's rotation rate to the tide-generating potential. Amplitudes and phases of kappa for the monthly, fortnightly, and nine-day lunar tides are estimated from 2 1/2 years of VLBI UT1 observations, corrected for atmospheric angular momentum effects using NMC wind and pressure series. Using the dynamic ocean tide model of Dickman (1988, 1989), amplitudes and phases of kappa for an elastic earth-ocean system are predicted. The predictions confirm earlier results which found that dynamic effects of the longer-period ocean tides reduce the amplitude of kappa by about 1 percent.

  7. Magnetic-field induced phase transitions in intermetallic rare-earth ferrimagnets with a compensation point

    Czech Academy of Sciences Publication Activity Database

    Sabdenov, Ch.K.; Davydova, M.D.; Zvezdin, K.A.; Gorbunov, Denis; Tereshina, I. S.; Andreev, Alexander V.; Zvezdin, A. K.

    2017-01-01

    Roč. 43, č. 5 (2017), s. 551-558 ISSN 1063-777X R&D Projects: GA ČR GA16-03593S Institutional support: RVO:68378271 Keywords : rare-earth intermetallics * phase diagram * field-induced transition * magnetic anisotropy * high magnetic fields Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 0.804, year: 2016

  8. Radio-luminescence efficiency and rare-earth dispersion in Tb-doped silica glasses

    Czech Academy of Sciences Publication Activity Database

    Fasoli, M.; Moretti, F.; Lauria, A.; Chiodini, N.; Vedda, A.; Nikl, Martin

    2007-01-01

    Roč. 42, - (2007), s. 784-787 ISSN 1350-4487 Institutional research plan: CEZ:AV0Z10100521 Keywords : sol-gel * scintillators * silica * rare earths * terbium Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.054, year: 2007

  9. Fertilization of Earth Ponds. II: Effects on Plankton Communities ...

    African Journals Online (AJOL)

    A study of the effects of slurry inorganic and organic of fertilizers on the production of phyto-and zooplankton in earth ponds was conducted in Central Scotland, U.K. over a period of one year. For the inorganic fertilization, replicate ponds were treated with low and high phosphorus (LP, HP), high phosphorus and nitrogen ...

  10. Interacting dark matter disguised as warm dark matter

    International Nuclear Information System (INIS)

    Boehm, Celine; Riazuelo, Alain; Hansen, Steen H.; Schaeffer, Richard

    2002-01-01

    We explore some of the consequences of dark-matter-photon interactions on structure formation, focusing on the evolution of cosmological perturbations and performing both an analytical and a numerical study. We compute the cosmic microwave background anisotropies and matter power spectrum in this class of models. We find, as the main result, that when dark matter and photons are coupled, dark matter perturbations can experience a new damping regime in addition to the usual collisional Silk damping effect. Such dark matter particles (having quite large photon interactions) behave like cold dark matter or warm dark matter as far as the cosmic microwave background anisotropies or matter power spectrum are concerned, respectively. These dark-matter-photon interactions leave specific imprints at sufficiently small scales on both of these two spectra, which may allow us to put new constraints on the acceptable photon-dark-matter interactions. Under the conservative assumption that the abundance of 10 12 M · galaxies is correctly given by the cold dark matter, and without any knowledge of the abundance of smaller objects, we obtain the limit on the ratio of the dark-matter-photon cross section to the dark matter mass σ γ-DM /m DM -6 σ Th /(100 GeV)≅6x10 -33 cm 2 GeV -1

  11. Turning the Star Trek Dream into Reality by Understanding Matter & Antimatter

    Science.gov (United States)

    Hansen, Norm

    2002-04-01

    People are going to learn all about matter and antimatter. Where matter and antimatter comes from. Where antimatter exists within our solar system. What the Periodic Table of Matter-AntiMatter Elements looks like. What each of the 109 antimatter element's nuclear, physical, and chemical characteristics are. How much energy is produced from matter and antimatter. And what needs to be done to turn the Star Trek Dream into Reality. The Milky Way Galaxy is composed of matter and antimatter. At the center of the galaxy, there are two black holes. One black hole is composed of matter; and the other is antimatter. The black holes are ejecting matter and antimatter into space forming a halo and spiral arms of matter & antimatter stars. The sun is one of the billions of stars that are composed of matter. There are a similar number of antimatter stars. Our Solar System contains the sun, earth, planets, and asteroids that are composed of matter, and comets that are composed of antimatter. When galactic antimatter enters our solar system, the antimatter is called comets. Astronomers have observed hundred of comets orbiting the sun and are finding new comets every year. During the last century, mass destruction has resulted when antimatter collided with Jupiter and Earth. How Humanity deals with the opportunities and dangers of antimatter will determine our destiny. Mankind has known about comets destructive power for thousands of years going back to the days of antiquity. Did comets have anything to do with the disappearance of Atlantis over twelve thousand years ago? We may never know; but is there a similar situation about to take place? Scientists have been studying antimatter by producing, storing, and colliding small quantities at national laboratories for several decades. Symmetry exists between matter and antimatter. Science and Technology provides unlimited opportunities to benefit humanity. Antimatter can be used, as a natural source of energy, to bring every country

  12. Evaluation of Mercury Contamination in Fungi Boletus Species from Latosols, Lateritic Red Earths, and Red and Yellow Earths in the Circum-Pacific Mercuriferous Belt of Southwestern China.

    Directory of Open Access Journals (Sweden)

    Jerzy Falandysz

    Full Text Available For the first time, highly elevated levels of mercury (Hg have been documented for several species of the edible Fungi genus Boletus growing in latosols, lateritic red earths, and red and yellow earths from the Yunnan province of China. Analysis of Hg concentrations in the genus suggests that geogenic Hg is the dominant source of Hg in the fungi, whereas anthropogenic sources accumulate largely in the organic layer of the forest soil horizon. Among the 21 species studied from 32 locations across Yunnan and 2 places in Sichuan Province, the Hg was found at elevated level in all samples from Yunnan but not in the samples from Sichuan, which is located outside the mercuriferous belt. Particularly abundant in Hg were the caps of fruiting bodies of Boletus aereus (up to 13 mg kg-1 dry matter, Boletus bicolor (up to 5.5 mg kg-1 dry matter, Boletus edulis (up to 22 mg kg-1 dry matter, Boletus luridus (up to 11 mg kg-1 dry matter, Boletus magnificus (up to 13 mg kg-1 dry matter, Boletus obscureumbrinus (up to 9.4 mg kg-1 dry matter, Boletus purpureus (up to 16 mg kg-1 dry matter, Boletus sinicus (up to 6.8 mg kg-1 dry matter, Boletus speciosus (up to 4.9mg kg-1 dry matter, Boletus tomentipes (up to 13 mg kg-1 dry matter, and Boletus umbriniporus (up to 4.9 mg kg-1 dry matter. Soil samples of the 0-10 cm topsoil layer from the widely distributed locations had mercury levels ranging between 0.034 to 3.4 mg kg-1 dry matter. In Yunnan, both the soil parent rock and fruiting bodies of Boletus spp. were enriched in Hg, whereas the same species from Sichuan, located outside the mercuriferous belt, had low Hg concentrations, suggesting that the Hg in the Yunnan samples is mainly from geogenic sources rather than anthropogenic sources. However, the contribution of anthropogenically-derived Hg sequestered within soils of Yunnan has not been quantified, so more future research is required. Our results suggest that high rates of consumption of Boletus spp. from

  13. Evaluation of Mercury Contamination in Fungi Boletus Species from Latosols, Lateritic Red Earths, and Red and Yellow Earths in the Circum-Pacific Mercuriferous Belt of Southwestern China.

    Science.gov (United States)

    Falandysz, Jerzy; Zhang, Ji; Wang, Yuan-Zhong; Saba, Martyna; Krasińska, Grażyna; Wiejak, Anna; Li, Tao

    2015-01-01

    For the first time, highly elevated levels of mercury (Hg) have been documented for several species of the edible Fungi genus Boletus growing in latosols, lateritic red earths, and red and yellow earths from the Yunnan province of China. Analysis of Hg concentrations in the genus suggests that geogenic Hg is the dominant source of Hg in the fungi, whereas anthropogenic sources accumulate largely in the organic layer of the forest soil horizon. Among the 21 species studied from 32 locations across Yunnan and 2 places in Sichuan Province, the Hg was found at elevated level in all samples from Yunnan but not in the samples from Sichuan, which is located outside the mercuriferous belt. Particularly abundant in Hg were the caps of fruiting bodies of Boletus aereus (up to 13 mg kg-1 dry matter), Boletus bicolor (up to 5.5 mg kg-1 dry matter), Boletus edulis (up to 22 mg kg-1 dry matter), Boletus luridus (up to 11 mg kg-1 dry matter), Boletus magnificus (up to 13 mg kg-1 dry matter), Boletus obscureumbrinus (up to 9.4 mg kg-1 dry matter), Boletus purpureus (up to 16 mg kg-1 dry matter), Boletus sinicus (up to 6.8 mg kg-1 dry matter), Boletus speciosus (up to 4.9mg kg-1 dry matter), Boletus tomentipes (up to 13 mg kg-1 dry matter), and Boletus umbriniporus (up to 4.9 mg kg-1 dry matter). Soil samples of the 0-10 cm topsoil layer from the widely distributed locations had mercury levels ranging between 0.034 to 3.4 mg kg-1 dry matter. In Yunnan, both the soil parent rock and fruiting bodies of Boletus spp. were enriched in Hg, whereas the same species from Sichuan, located outside the mercuriferous belt, had low Hg concentrations, suggesting that the Hg in the Yunnan samples is mainly from geogenic sources rather than anthropogenic sources. However, the contribution of anthropogenically-derived Hg sequestered within soils of Yunnan has not been quantified, so more future research is required. Our results suggest that high rates of consumption of Boletus spp. from Yunnan can

  14. Astronomy Matters for Chemistry Teachers

    Science.gov (United States)

    Huebner, Jay S.; Vergenz, Robert A.; Smith, Terry L.

    1996-11-01

    The purpose of this paper is to encourage more chemistry teachers to become familiar with some of the basic ideas described in typical introductory astronomy courses (1 - 9), including those about the origin of elements and forms of matter. These ideas would enrich chemistry courses and help resolve some basic misconceptions that are expressed in many introductory texts (10 - 16) and journal articles for chemistry teachers (17, 18). These misconceptions are typified by statements such as "we can classify all substances as either elements or compounds," and "nature has provided 92 elements out of which all matter is composed." If students accept these misconceptions, they could be deprived of (i) an appreciation of the history of elements and knowing that the elemental composition of the universe continues to evolve, (ii) knowing that of the first 92 elements in the periodic table, technetium and promethium do not occur naturally on Earth, and (iii) understanding that there are forms of matter other than elements and compounds. This paper briefly explores these ideas.

  15. The Network Structure Underlying the Earth Observation Assessment

    Science.gov (United States)

    Vitkin, S.; Doane, W. E. J.; Mary, J. C.

    2017-12-01

    The Earth Observations Assessment (EOA 2016) is a multiyear project designed to assess the effectiveness of civil earth observation data sources (instruments, sensors, models, etc.) on societal benefit areas (SBAs) for the United States. Subject matter experts (SMEs) provided input and scored how data sources inform products, product groups, key objectives, SBA sub-areas, and SBAs in an attempt to quantify the relationships between data sources and SBAs. The resulting data were processed by Integrated Applications Incorporated (IAI) using MITRE's PALMA software to create normalized relative impact scores for each of these relationships. However, PALMA processing obscures the natural network representation of the data. Any network analysis that might identify patterns of interaction among data sources, products, and SBAs is therefore impossible. Collaborating with IAI, we cleaned and recreated a network from the original dataset. Using R and Python we explore the underlying structure of the network and apply frequent itemset mining algorithms to identify groups of data sources and products that interact. We reveal interesting patterns and relationships in the EOA dataset that were not immediately observable from the EOA 2016 report and provide a basis for further exploration of the EOA network dataset.

  16. Density profiles of supernova matter and determination of neutrino parameters

    Science.gov (United States)

    Chiu, Shao-Hsuan

    2007-08-01

    The flavor conversion of supernova neutrinos can lead to observable signatures related to the unknown neutrino parameters. As one of the determinants in dictating the efficiency of resonant flavor conversion, the local density profile near the Mikheyev-Smirnov-Wolfenstein (MSW) resonance in a supernova environment is, however, not so well understood. In this analysis, variable power-law functions are adopted to represent the independent local density profiles near the locations of resonance. It is shown that the uncertain matter density profile in a supernova, the possible neutrino mass hierarchies, and the undetermined 1-3 mixing angle would result in six distinct scenarios in terms of the survival probabilities of νe and ν¯e. The feasibility of probing the undetermined neutrino mass hierarchy and the 1-3 mixing angle with the supernova neutrinos is then examined using several proposed experimental observables. Given the incomplete knowledge of the supernova matter profile, the analysis is further expanded to incorporate the Earth matter effect. The possible impact due to the choice of models, which differ in the average energy and in the luminosity of neutrinos, is also addressed in the analysis.

  17. Effect of rare earth oxide additives on the performance of NiMH batteries

    International Nuclear Information System (INIS)

    Tanaka, Toshiki; Kuzuhara, Minoru; Watada, Masaharu; Oshitani, Masahiko

    2006-01-01

    To date, we have performed research on nickel-metal hydride (NiMH) batteries used in many applications and have found that addition of rare earth oxides to the nickel electrode and the hydrogen-storage alloy (MH) electrode improves battery performance significantly. Because heavy rare earth oxides of such as Er, Tm, Yb and Lu have remarkable properties that shift the oxygen evolution overpotentials of nickel electrodes to more noble potentials, it is possible to improve high-temperature charge efficiency of nickel-metal hydride secondary batteries by adding them to nickel electrodes. Furthermore, addition of heavy rare earth oxides to MH electrodes depresses an acceleration of the alloy corrosion and improves service life of the battery at high temperatures. Accordingly, addition of heavy rare earth oxides is effective for NiMH batteries used in high-temperature applications such as electric vehicles (EVs), hybrid vehicles (HEVs) and rapid charge devices. In this study, we discussed how the addition of heavy rare earth oxides affects NiMH battery characteristics

  18. Effect of Sporosarcina Pasteurii on the strength properties of compressed earth specimens

    International Nuclear Information System (INIS)

    Bernat-Maso, E.; Gil, L.; Escrig, C.; Barbé, J.; Cortés, P.

    2018-01-01

    Microbial biodeposition of calcite induction for improving the performance of rammed earth is a research area that must be analysed in a representative environment. This analysis must consider the compaction force, particle size distribution and curing process as production variables. This paper investigates the effects of adding specific bacteria, Sporosarcina Pasteurii, into compressed earth cubes and the effect of production variables. Uniaxial compressive tests and direct shear tests have been conducted for 80 specimens. The results indicate that calcite precipitation interacts with the drying process of clay/silt resulting in reducing the compressive strength, the apparent cohesion and the friction angle. Finally, bacterial activity, which is more likely in samples cured in a high humidity environment, tends to reduce the dilatancy effect. [es

  19. Rare earths

    International Nuclear Information System (INIS)

    1984-01-01

    The conference was held from September 12 to 13, 1984 in Jetrichovice, Czechoslovakia. The participants heard 16 papers of which 4 were inputted in INIS. These papers dealt with industrial separation processes of rare earths, the use of chemical methods of separation from the concentrate of apatite and bastnesite, the effect of the relative permittivity of solvents in the elution of rare earth elements from a cation exchanger, and the determination of the content of different rare earth elements using X-ray fluorescence analysis and atomic absorption spectroscopy. (E.S.)

  20. Co-Seismic Mass Dislocation and its Effect on Earth's Rotation and Gravity

    Science.gov (United States)

    Chao, B. F.; Gross, R. S.

    2002-01-01

    Mantle processes often involve large-scale mass transport, ranging from mantle convection, tectonic motions, glacial isostatic adjustment, to tides, atmospheric and oceanic loadings, volcanism and seismicity. On very short time scale of less than an hour, co-seismic event, apart from the shaking that is the earthquake, leaves behind permanent (step-function-like) dislocations in the crust and mantle. This redistribution of mass changes the Earth's inertia tensor (and hence Earth's rotation in both length-of-day and polar motion), and the gravity field (in terms of spherical harmonic Stokes coefficients). The question is whether these effects are large enough to be of any significance. In this paper we report updated calculation results based on Chao & Gross (1987). The calculation uses the normal mode summation scheme, applied to nearly twenty thousand major earthquakes that occurred during 1976-2002, according to source mechanism solutions given by the Harvard Central Moment Tensor catalog. Compared to the truly large ones earlier in the century, the earthquakes we study are individually all too small to have left any discernible signature in geodetic records of Earth rotation or global gravity field. However, their collective effects continue to exhibit an extremely strong statistical tendencies. For example, earthquakes conspire to decrease J2 and J22 while shortening LOD, resulting in a rounder and more compact Earth. Strong tendency is also seen in the earthquakes trying to nudge the Earth rotation pole towards approximately 140 degrees E, roughly opposite to the observed polar drift direction. The geophysical significance and implications will be further studied.

  1. Astrometric detectability of systems with unseen companions: effects of the Earth orbital motion

    Science.gov (United States)

    Butkevich, Alexey G.

    2018-06-01

    The astrometric detection of an unseen companion is based on an analysis of the apparent motion of its host star around the system's barycentre. Systems with an orbital period close to 1 yr may escape detection if the orbital motion of their host stars is observationally indistinguishable from the effects of parallax. Additionally, an astrometric solution may produce a biased parallax estimation for such systems. We examine the effects of the orbital motion of the Earth on astrometric detectability in terms of a correlation between the Earth's orbital position and the position of the star relative to its system barycentre. The χ2 statistic for parallax estimation is calculated analytically, leading to expressions that relate the decrease in detectability and accompanying parallax bias to the position correlation function. The impact of the Earth's motion critically depends on the exoplanet's orbital period, diminishing rapidly as the period deviates from 1 yr. Selection effects against 1-yr-period systems is, therefore, expected. Statistical estimation shows that the corresponding loss of sensitivity results in a typical 10 per cent increase in the detection threshold. Consideration of eccentric orbits shows that the Earth's motion has no effect on detectability for e≳ 0.5. The dependence of the detectability on other parameters, such as orbital phases and inclination of the orbital plane to the ecliptic, are smooth and monotonic because they are described by simple trigonometric functions.

  2. Radioactive waste, the earth's crust, and the human society

    International Nuclear Information System (INIS)

    Rometsch, R.

    1986-01-01

    Four billion human beings are living in a thin layer around the planet Earth. Life has always been at risk in several ways in the limited space defined by the interface between the earth and the atmosphere: Cosmic changes could be so overwhelming that we do not even want to consider them. We have learned to live and die in natural catastrophes caused by the continuous movement of matter in the outer part of the earth's crust and the surrounding biosphere. And there are those effects resulting from human activities. Although we do not like to admit it, perhaps the greatest danger lies in the human character itself; the root of killing and wars. The growing number of human beings gives rise to a greater impact on the environment. The nuclear debate has sharpened our wits with regard to the special case of radioactive wastes, perceived by large parts of the population as a particular threat. Hence, their management and disposal has become a test case to prove that human society is capable of keeping the environment essentially free of these waste products. This explains the worldwide efforts in this field - and also this conference. The results already achieved with regard to radioactive wastes justifies hopes that it will become possible, technically as well as politically, to control all kinds of toxic by-products of our technical civilization

  3. Effect of Rare Earth Metals on the Microstructure of Al-Si Based Alloys

    Directory of Open Access Journals (Sweden)

    Saleh A. Alkahtani

    2016-01-01

    Full Text Available The present study was performed on A356 alloy [Al-7 wt %Si 0.0.35 wt %Mg]. To that La and Ce were added individually or combined up to 1.5 wt % each. The results show that these rare earth elements affect only the alloy melting temperature with no marked change in the temperature of Al-Si eutectic precipitation. Additionally, rare earth metals have no modification effect up to 1.5 wt %. In addition, La and Ce tend to react with Sr leading to modification degradation. In order to achieve noticeable modification of eutectic Si particles, the concentration of rare earth metals should exceed 1.5 wt %, which simultaneously results in the precipitation of a fairly large volume fraction of insoluble intermetallics. The precipitation of these complex intermetallics is expected to have a negative effect on the alloy performance.

  4. Analysis of earth albedo effect on sun sensor measurements based on theoretical model and mission experience

    Science.gov (United States)

    Brasoveanu, Dan; Sedlak, Joseph

    1998-01-01

    Analysis of flight data from previous missions indicates that anomalous Sun sensor readings could be caused by Earth albedo interference. A previous Sun sensor study presented a detailed mathematical model of this effect. The model can be used to study the effect of both diffusive and specular reflections and to improve Sun angle determination based on perturbed Sun sensor measurements, satellite position, and an approximate knowledge of attitude. The model predicts that diffuse reflected light can cause errors of up to 10 degrees in Coarse Sun Sensor (CSS) measurements and 5 to 10 arc sec in Fine Sun Sensor (FSS) measurements, depending on spacecraft orbit and attitude. The accuracy of these sensors is affected as long as part of the illuminated Earth surface is present in the sensor field of view. Digital Sun Sensors (DSS) respond in a different manner to the Earth albedo interference. Most of the time DSS measurements are not affected, but for brief periods of time the Earth albedo can cause errors which are a multiple of the sensor least significant bit and may exceed one degree. This paper compares model predictions with Tropical Rainfall Measuring Mission (TRMM) CSS measurements in order to validate and refine the model. Methods of reducing and mitigating the impact of Earth albedo are discussed. ne CSS sensor errors are roughly proportional to the Earth albedo coefficient. Photocells that are sensitive only to ultraviolet emissions would reduce the effective Earth albedo by up to a thousand times, virtually eliminating all errors caused by Earth albedo interference.

  5. NASA Earth Science Education Collaborative

    Science.gov (United States)

    Schwerin, T. G.; Callery, S.; Chambers, L. H.; Riebeek Kohl, H.; Taylor, J.; Martin, A. M.; Ferrell, T.

    2016-12-01

    The NASA Earth Science Education Collaborative (NESEC) is led by the Institute for Global Environmental Strategies with partners at three NASA Earth science Centers: Goddard Space Flight Center, Jet Propulsion Laboratory, and Langley Research Center. This cross-organization team enables the project to draw from the diverse skills, strengths, and expertise of each partner to develop fresh and innovative approaches for building pathways between NASA's Earth-related STEM assets to large, diverse audiences in order to enhance STEM teaching, learning and opportunities for learners throughout their lifetimes. These STEM assets include subject matter experts (scientists, engineers, and education specialists), science and engineering content, and authentic participatory and experiential opportunities. Specific project activities include authentic STEM experiences through NASA Earth science themed field campaigns and citizen science as part of international GLOBE program (for elementary and secondary school audiences) and GLOBE Observer (non-school audiences of all ages); direct connections to learners through innovative collaborations with partners like Odyssey of the Mind, an international creative problem-solving and design competition; and organizing thematic core content and strategically working with external partners and collaborators to adapt and disseminate core content to support the needs of education audiences (e.g., libraries and maker spaces, student research projects, etc.). A scaffolded evaluation is being conducted that 1) assesses processes and implementation, 2) answers formative evaluation questions in order to continuously improve the project; 3) monitors progress and 4) measures outcomes.

  6. Understanding Earth's Albedo Effect

    Science.gov (United States)

    Fidler, Chuck

    2012-01-01

    Earth and space science in the middle school classroom are composed of intricately intertwined sets of conceptual systems (AAAS 1993; NRC 1996). Some systems of study, such as the water and rock cycles, are quite explicit and often found as stand-alone middle school science units. Other phenomena are not so apparent, yet they play an extremely…

  7. Crystal field and magnetism with Wannier functions: rare-earth dopedaluminum garnets

    Czech Academy of Sciences Publication Activity Database

    Mihóková, Eva; Novák, Pavel; Laguta, Valentyn

    2015-01-01

    Roč. 33, č. 12 (2015), 1316-1323 ISSN 1002-0721 R&D Projects: GA ČR GA13-09876S Institutional support: RVO:68378271 Keywords : crystal field * ab initio calculations * garnets * rare earths Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.188, year: 2015

  8. Spaceflight Effect on White Matter Structural Integrity

    Science.gov (United States)

    Lee, Jessica K.; Kopplemans, Vincent; Paternack, Ofer; Bloomberg, Jacob J.; Mulavara, Ajitkumar P.; Seidler, Rachael D.

    2017-01-01

    Recent reports of elevated brain white matter hyperintensity (WMH) counts and volume in postflight astronaut MRIs suggest that further examination of spaceflight's impact on the microstructure of brain white matter is warranted. To this end, retrospective longitudinal diffusion-weighted MRI scans obtained from 15 astronauts were evaluated. In light of the recent reports of microgravity-induced cephalad fluid shift and gray matter atrophy seen in astronauts, we applied a technique to estimate diffusion tensor imaging (DTI) metrics corrected for free water contamination. This approach enabled the analysis of white matter tissue-specific alterations that are unrelated to fluid shifts, occurring from before spaceflight to after landing. After spaceflight, decreased fractional anisotropy (FA) values were detected in an area encompassing the superior and inferior longitudinal fasciculi and the inferior fronto-occipital fasciculus. Increased radial diffusivity (RD) and decreased axial diffusivity (AD) were also detected within overlapping regions. In addition, FA values in the corticospinal tract decreased and RD measures in the precentral gyrus white matter increased from before to after flight. The results show disrupted structural connectivity of white matter in tracts involved in visuospatial processing, vestibular function, and movement control as a result of spaceflight. The findings may help us understand the structural underpinnings of the extensive spaceflight-induced sensorimotor remodeling. Prospective longitudinal assessment of the white matter integrity in astronauts is needed to characterize the evolution of white matter microstructural changes associated with spaceflight, their behavioral consequences, and the time course of recovery. Supported by a grant from the National Space Biomedical Research Institute, NASA NCC 9-58.

  9. Effect of selective removal of organic matter and iron oxides on the ...

    African Journals Online (AJOL)

    The effect of selective removal of organic matter and amorphous and crystalline iron oxides on N2-BET specific surface areas of some soil clays was evaluated. Clay fractions from 10 kaolinitic tropical soils were successively treated to remove organic matter by oxidation with Na hypochlorite, amorphous Fe oxide with acid ...

  10. Ecological effect of rare earth elements

    International Nuclear Information System (INIS)

    Hu Aitang; Zhou Quansuo; Zheng Shaojian; Zhai Hai; Zhao Xiulan; Pang Yonglin; Wang Yuqi; Sun Jingxin; Zhang Shen; Wang Lijun

    1997-01-01

    Water and soil culture were carried out to study the ecological effect of rare earth elements (REEs) in the aspect of plant-soil system. Contents of REEs were determined by instrumental neutron activation analysis (INAA). There was a limit to REEs-tolerance of crops, which differed with the development periods of plant and soil types. The REEs concentration in plant, especially in root, was marked related to the concentration in culture material. Beyond the concentration-limit appeared phototoxicity. The chemical behavior of REEs in plants and soils varied with soil types and elements. The bio-availability of REEs in soil mainly depended on the exchangeable fraction of REEs affected strongly by the physi-chemical properties of soils

  11. Earthing the human body influences physiologic processes.

    Science.gov (United States)

    Sokal, Karol; Sokal, Pawel

    2011-04-01

    This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments: Five (5) experiments are presented: experiment 1-effect of earthing on calcium-phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2-effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3-effect of earthing on thyroid function (N = 12); experiment 4-effect of earthing on glucose concentration (N = 12); experiment 5-effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium-phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems.

  12. Effects of Long Period Ocean Tides on the Earth's Rotation

    Science.gov (United States)

    Gross, Richard S.; Chao, Ben F.; Desai, Shailen D.

    1996-01-01

    The spectra of polar motion excitation functions exhibit enhanced power in the fortnightly tidal band. This enhanced power is attributed to ocean tidal excitation. Ocean tide models predict polar motion excitation effects that differ with each other, and with observations, by factors as large as 2-3. There is a need for inproved models for the effect of long-period ocean tides on Earth's rotation.

  13. Effects of effluent organic matter characteristics on the removal of bulk organic matter and selected pharmaceutically active compounds during managed aquifer recharge: Column study

    KAUST Repository

    Maeng, Sungkyu; Sharma, Saroj K.; Abel, Chol D T; Magic-Knezev, Aleksandra; Song, Kyungguen; Amy, Gary L.

    2012-01-01

    Soil column experiments were conducted to investigate the effects of effluent organic matter (EfOM) characteristics on the removal of bulk organic matter (OM) and pharmaceutically active compounds (PhACs) during managed aquifer recharge (MAR

  14. Solar Neutrino Observables Sensitive to Matter Effects

    Directory of Open Access Journals (Sweden)

    H. Minakata

    2012-01-01

    Full Text Available We discuss constraints on the coefficient AMSW which is introduced to simulate the effect of weaker or stronger matter potential for electron neutrinos with the current and future solar neutrino data. The currently available solar neutrino data leads to a bound AMSW=1.47+0.54−0.42(+1.88−0.82 at 1σ (3σ CL, which is consistent with the Standard Model prediction AMSW=1. For weaker matter potential (AMSW1, the bound is milder and is dominated by the day-night asymmetry of 8B neutrino flux recently observed by Super-Kamiokande. Among the list of observables of ongoing and future solar neutrino experiments, we find that (1 an improved precision of the day-night asymmetry of 8B neutrinos, (2 precision measurements of the low-energy quasi-monoenergetic neutrinos, and (3 the detection of the upturn of the 8B neutrino spectrum at low energies are the best choices to improve the bound on AMSW.

  15. Collective effects on transport coefficients of relativistic nuclear matter. Pt. 2

    International Nuclear Information System (INIS)

    Mornas, L.

    1993-04-01

    The transport coefficients (thermal conductivity, shear and bulk viscosities) of symmetric nuclear matter and neutron matter are calculated in the Walecka model with a Boltzmann-Uehling-Uhlenbeck collision term by means of a Chapman-Enskog expansion in first order. The order of magnitude of the influence of collective effects induced by the presence of the mean σ and ω fields on these coefficients is evaluated. (orig.). 9 figs

  16. Capturing near-Earth asteroids around Earth

    Science.gov (United States)

    Hasnain, Zaki; Lamb, Christopher A.; Ross, Shane D.

    2012-12-01

    The list of detected near-Earth asteroids (NEAs) is constantly growing. NEAs are likely targets for resources to support space industrialization, as they may be the least expensive source of certain needed raw materials. The limited supply of precious metals and semiconducting elements on Earth may be supplemented or even replaced by the reserves floating in the form of asteroids around the solar system. Precious metals make up a significant fraction NEAs by mass, and even one metallic asteroid of ˜1km size and fair enrichment in platinum-group metals would contain twice the tonnage of such metals already harvested on Earth. There are ˜1000 NEAs with a diameter of greater than 1 km. Capturing these asteroids around the Earth would expand the mining industry into an entirely new dimension. Having such resources within easy reach in Earth's orbit could provide an off-world environmentally friendly remedy for impending terrestrial shortages, especially given the need for raw materials in developing nations. In this paper, we develop and implement a conceptually simple algorithm to determine trajectory characteristics necessary to move NEAs into capture orbits around the Earth. Altered trajectories of asteroids are calculated using an ephemeris model. Only asteroids of eccentricity less than 0.1 have been studied and the model is restricted to the ecliptic plane for simplicity. We constrain the time of retrieval to be 10 years or less, based on considerations of the time to return on investment. For the heliocentric phase, constant acceleration is assumed. The acceleration required for transporting these asteroids from their undisturbed orbits to the sphere of influence of the Earth is the primary output, along with the impulse or acceleration necessary to effect capture to a bound orbit once the Earth's sphere of influence is reached. The initial guess for the constant acceleration is provided by a new estimation method, similar in spirit to Edelbaum's. Based on the

  17. Shining a light on mysterious "Dark Matter"

    CERN Multimedia

    2007-01-01

    "We've all been taught that our bodies, the Earth, and in fact all matter in the universe is comnposed of tiny building blocks called atoms. Now imagine if this weren't the case. This mind-bending concept is at the core of the scientific research that one Florida State University progessor - and hundreds of his colleagues all over the world - is pursuing."(1 page)

  18. A man from planet earth a scientific novel

    CERN Document Server

    Genta, Giancarlo

    2016-01-01

    Sometime in the not-too-distant future ... unbeknownst to Earth, the Galaxy is home to a number of spacefaring societies. This confederation enforces a strict protocol forbidding any contact with civilizations that have not yet achieved both a substantial spacefaring capability and sufficient maturity to control the technology explosion before triggering their own extinction.   While this policy is intended to only bring in peaceful new members, matters change entirely when the confederation is threatened by some unknown entity - is the menace real or imagined?  The confederation decides to break with the rules and sends a delegate to Earth to hire one of the supposedly belligerent Earthlings to investigate and to revive the confederation’s long-unused starfleet. The Earthman agrees, but demands a high price: should he succeed, the confederation will have to accept Earth as a new member. As the threat becomes ever more acute, the question soon becomes which mission will prove harder - saving the confedera...

  19. Spectrophotometric method for the analysis of rare earths by first and second order derivatives

    International Nuclear Information System (INIS)

    Deshpande, S.M.; Singh, H.

    1997-01-01

    Spectrophotometric methods are widely used for the analysis of rare earth elements as they are simple, fast, precise and accurate. Many of the rare earth ions in acidic solutions absorb in ultraviolet and visible region of the electromagnetic spectrum. Because of the restricted transition of the 4f electrons the absorption peaks are very sharp and these peaks are used for the qualitative and quantitative analysis of rare elements. When analysis of one or two minor constituents in the mixture of rare earths is involved, it is a straightforward and simple matter, but the analysis of multiple elements from a complex mixture is very difficult because of the mutual interference of the absorption bands. Simultaneous equations of the type: (OD) 1 = C A X Φ A1 + C B X Φ B1 and (OD) 2 = C A X Φ A2 + C B X Φ B2 are also employed to overcome the mutual interference. In this paper first order and second order derivative spectra are used for the analysis of rare earths. It is a simple and effective technique for accurate analysis of rare earths from a complex mixture. Absorption data in the first derivative mode is also presented. Analysis of Nd-Pr-Sm from their synthetic mixtures is reported. (author). 4 refs., 1 tab., 1 ill

  20. The effect of recent Venus transit on Earth’s atmosphere

    Directory of Open Access Journals (Sweden)

    H. P. Sardar

    2006-06-01

    Full Text Available Some experiments on June 8, 2004, the day of transit of Venus across the Sun, were undertaken at Kolkata (latitude: 22°34lN to observe the effect, if any, of transit of Venus on FWF, ELF and VLF amplitudes. The result shows a good correlation between their temporal variations during the transit. The observation was unbelievable as the Venus subtends only 1/32th of the cone subtended by Sun on Earth. This anomaly may be explained on the assumption that the height of Venusian atmosphere with high content of CO2, and nitrogen which absorbs electromagnetic and corpuscular radiations from Sun, depleting the solar radiation reaching the Earth to a considerable extent. As a result, relevant parameters of Earth’s atmosphere are modulated and here we show how these changes are reflected in identical behaviour of fair weather field and ELF and VLF spectra.

  1. Effects of Zonal Deformations and the Earth's Rotation Rate Variations on Precession-Nutation

    National Research Council Canada - National Science Library

    Lambert, S

    2004-01-01

    .... This paper considers the coupling effects between the axial and the equatorial components of the Earth's rotation vector in the dynamical equations, and the effects of the second order lunisolar...

  2. Earthing the Human Body Influences Physiologic Processes

    Science.gov (United States)

    Sokal, Karol

    2011-01-01

    Abstract Objectives This study was designed to answer the question: Does the contact of the human organism with the Earth via a copper conductor affect physiologic processes? Subjects and experiments Five (5) experiments are presented: experiment 1—effect of earthing on calcium–phosphate homeostasis and serum concentrations of iron (N = 84 participants); experiment 2—effect of earthing on serum concentrations of electrolytes (N = 28); experiment 3—effect of earthing on thyroid function (N = 12); experiment 4—effect of earthing on glucose concentration (N = 12); experiment 5—effect of earthing on immune response to vaccine (N = 32). Subjects were divided into two groups. One (1) group of people was earthed, while the second group remained without contact with the Earth. Blood and urine samples were examined. Results Earthing of an electrically insulated human organism during night rest causes lowering of serum concentrations of iron, ionized calcium, inorganic phosphorus, and reduction of renal excretion of calcium and phosphorus. Earthing during night rest decreases free tri-iodothyronine and increases free thyroxine and thyroid-stimulating hormone. The continuous earthing of the human body decreases blood glucose in patients with diabetes. Earthing decreases sodium, potassium, magnesium, iron, total protein, and albumin concentrations while the levels of transferrin, ferritin, and globulins α1, α2, β, and γ increase. These results are statistically significant. Conclusions Earthing the human body influences human physiologic processes. This influence is observed during night relaxation and during physical activity. Effect of the earthing on calcium–phosphate homeostasis is the opposite of that which occurs in states of weightlessness. It also increases the activity of catabolic processes. It may be the primary factor regulating endocrine and nervous systems. PMID:21469913

  3. iTIMP: isotriplet Technicolor Interacting Massive Particle as Dark Matter

    DEFF Research Database (Denmark)

    T. Frandsen, Mads; Sannino, Francesco

    2010-01-01

    We suggest that a weak isotriplet composite scalar possessing an unbroken U(1) global symmetry naturally arises in technicolor models leading to an interesting type of dark matter candidate: the iTIMP. We propose explicit models of the iTIMP, study earth based constraints and suggest possible...

  4. Cold Nuclear Matter Effects on J/psi Production: Intrinsic and Extrinsic Transverse Momentum Effects

    Energy Technology Data Exchange (ETDEWEB)

    Ferreiro, E.G.; /Santiago de Compostela U.; Fleuret, F.; /Ecole Polytechnique; Lansberg, J.P.; /Heidelberg U.; Rakotozafindrabe, A.; /SPhN, DAPNIA, Saclay

    2010-08-26

    Cold nuclear matter effects on J/{psi} production in proton-nucleus and nucleus-nucleus collisions are evaluated taking into account the specific J/{psi}-production kinematics at the partonic level, the shadowing of the initial parton distributions and the absorption in the nuclear matter. We consider two different parton processes for the c{bar c}-pair production: one with collinear gluons and a recoiling gluon in the final state and the other with initial gluons carrying intrinsic transverse momentum. Our results are compared to RHIC observables. The smaller values of the nuclear modification factor R{sub AA} in the forward rapidity region (with respect to the mid rapidity region) are partially explained, therefore potentially reducing the need for recombination effects.

  5. On a possible connection between Chandler wobble and dark matter

    International Nuclear Information System (INIS)

    Portilho, Oyanarte

    2009-01-01

    Chandler wobble excitation and damping, one of the open problems in geophysics, is treated as a consequence in part of the interaction between Earth and a hypothetical oblate ellipsoid made of dark matter. The physical and geometrical parameters of such an ellipsoid and the interacting torque strength is calculated in such a way to reproduce the Chandler wobble component of the polar motion in several epochs, available in the literature. It is also examined the consequences upon the geomagnetic field dynamo and generation of heat in the Earth outer core. (author)

  6. Dark matter directional detection in non-relativistic effective theories

    International Nuclear Information System (INIS)

    Catena, Riccardo

    2015-01-01

    We extend the formalism of dark matter directional detection to arbitrary one-body dark matter-nucleon interactions. The new theoretical framework generalizes the one currently used, which is based on 2 types of dark matter-nucleon interaction only. It includes 14 dark matter-nucleon interaction operators, 8 isotope-dependent nuclear response functions, and the Radon transform of the first 2 moments of the dark matter velocity distribution. We calculate the recoil energy spectra at dark matter directional detectors made of CF 4 , CS 2 and 3 He for the 14 dark matter-nucleon interactions, using nuclear response functions recently obtained through numerical nuclear structure calculations. We highlight the new features of the proposed theoretical framework, and present our results for a spherical dark matter halo and for a stream of dark matter particles. This study lays the foundations for model independent analyses of dark matter directional detection experiments

  7. Parametric resonance in neutrino oscillation: A guide to control the effects of inhomogeneous matter density

    International Nuclear Information System (INIS)

    Koike, Masafumi; Ota, Toshihiko; Saito, Masako; Sato, Joe

    2016-01-01

    Effects of the inhomogeneous matter density on the three-generation neutrino oscillation probability are analyzed. Realistic profile of the matter density is expanded into a Fourier series. Taking in the Fourier modes one by one, we demonstrate that each mode has its corresponding target energy. The high Fourier mode selectively modifies the oscillation probability of the low-energy region. This rule is well described by the parametric resonance between the neutrino oscillation and the matter effect. The Fourier analysis gives a simple guideline to systematically control the uncertainty of the oscillation probability caused by the uncertain density of matter. Precise analysis of the oscillation probability down to the low-energy region requires accurate evaluation of the Fourier coefficients of the matter density up to the corresponding high modes.

  8. Effects of Surgery and Proton Therapy on Cerebral White Matter of Craniopharyngioma Patients

    Energy Technology Data Exchange (ETDEWEB)

    Uh, Jinsoo, E-mail: jinsoo.uh@stjude.org [Department of Radiological Sciences, St Jude Children' s Research Hospital, Memphis, Tennessee (United States); Merchant, Thomas E. [Department of Radiological Sciences, St Jude Children' s Research Hospital, Memphis, Tennessee (United States); Li, Yimei; Li, Xingyu [Department of Biostatistics, St Jude Children' s Research Hospital, Memphis, Tennessee (United States); Sabin, Noah D. [Department of Radiological Sciences, St Jude Children' s Research Hospital, Memphis, Tennessee (United States); Indelicato, Daniel J. [Department of Radiation Oncology, University of Florida, Jacksonville, Florida (United States); Ogg, Robert J. [Department of Radiological Sciences, St Jude Children' s Research Hospital, Memphis, Tennessee (United States); Boop, Frederick A. [Semmes-Murphey Neurologic and Spine Institute, Memphis, Tennessee (United States); Jane, John A. [Department of Neurosurgery, University of Virginia, Charlottesville, Virginia (United States); Hua, Chiaho [Department of Radiological Sciences, St Jude Children' s Research Hospital, Memphis, Tennessee (United States)

    2015-09-01

    Purpose: The purpose of this study was to determine radiation dose effect on the structural integrity of cerebral white matter in craniopharyngioma patients receiving surgery and proton therapy. Methods and Materials: Fifty-one patients (2.1-19.3 years of age) with craniopharyngioma underwent surgery and proton therapy in a prospective therapeutic trial. Anatomical magnetic resonance images acquired after surgery but before proton therapy were inspected to identify white matter structures intersected by surgical corridors and catheter tracks. Longitudinal diffusion tensor imaging (DTI) was performed to measure microstructural integrity changes in cerebral white matter. Fractional anisotropy (FA) derived from DTI was statistically analyzed for 51 atlas-based white matter structures of the brain to determine radiation dose effect. FA in surgery-affected regions in the corpus callosum was compared to that in its intact counterpart to determine whether surgical defects affect radiation dose effect. Results: Surgical defects were seen most frequently in the corpus callosum because of transcallosal resection of tumors and insertion of ventricular or cyst catheters. Longitudinal DTI data indicated reductions in FA 3 months after therapy, which was followed by a recovery in most white matter structures. A greater FA reduction was correlated with a higher radiation dose in 20 white matter structures, indicating a radiation dose effect. The average FA in the surgery-affected regions before proton therapy was smaller (P=.0001) than that in their non–surgery-affected counterparts with more intensified subsequent reduction of FA (P=.0083) after therapy, suggesting that surgery accentuated the radiation dose effect. Conclusions: DTI data suggest that mild radiation dose effects occur in patients with craniopharyngioma receiving surgery and proton therapy. Surgical defects present at the time of proton therapy appear to accentuate the radiation dose effect longitudinally

  9. Effects of Surgery and Proton Therapy on Cerebral White Matter of Craniopharyngioma Patients

    International Nuclear Information System (INIS)

    Uh, Jinsoo; Merchant, Thomas E.; Li, Yimei; Li, Xingyu; Sabin, Noah D.; Indelicato, Daniel J.; Ogg, Robert J.; Boop, Frederick A.; Jane, John A.; Hua, Chiaho

    2015-01-01

    Purpose: The purpose of this study was to determine radiation dose effect on the structural integrity of cerebral white matter in craniopharyngioma patients receiving surgery and proton therapy. Methods and Materials: Fifty-one patients (2.1-19.3 years of age) with craniopharyngioma underwent surgery and proton therapy in a prospective therapeutic trial. Anatomical magnetic resonance images acquired after surgery but before proton therapy were inspected to identify white matter structures intersected by surgical corridors and catheter tracks. Longitudinal diffusion tensor imaging (DTI) was performed to measure microstructural integrity changes in cerebral white matter. Fractional anisotropy (FA) derived from DTI was statistically analyzed for 51 atlas-based white matter structures of the brain to determine radiation dose effect. FA in surgery-affected regions in the corpus callosum was compared to that in its intact counterpart to determine whether surgical defects affect radiation dose effect. Results: Surgical defects were seen most frequently in the corpus callosum because of transcallosal resection of tumors and insertion of ventricular or cyst catheters. Longitudinal DTI data indicated reductions in FA 3 months after therapy, which was followed by a recovery in most white matter structures. A greater FA reduction was correlated with a higher radiation dose in 20 white matter structures, indicating a radiation dose effect. The average FA in the surgery-affected regions before proton therapy was smaller (P=.0001) than that in their non–surgery-affected counterparts with more intensified subsequent reduction of FA (P=.0083) after therapy, suggesting that surgery accentuated the radiation dose effect. Conclusions: DTI data suggest that mild radiation dose effects occur in patients with craniopharyngioma receiving surgery and proton therapy. Surgical defects present at the time of proton therapy appear to accentuate the radiation dose effect longitudinally

  10. Geochemistry of rare earth elements in the mainstream of the Yangtze River, China

    International Nuclear Information System (INIS)

    Li, X.; Zhang, S.; Wang, L.; Zhang, C.

    1998-01-01

    Water, suspended matter, and sediment samples were taken from 8 locations along the Yangtze River in 1992. The concentration and speciation (exchangeable, bound to carbonates, bound to Fe-Mn oxides, bound to organic matter, and residual forms) of rare earth elements (La, Ce, Nd, Sm, Eu, Tb, Yb, and Lu) were determined by instrumental neutron activation analysis (INAA).The contents of the soluble fraction of REEs in the river are low, and REEs mainly reside in particulate form. In the particles, the chondrite-normalized distribution patterns show significant LREE enrichment and Eu-depletion. While normalized to shales, both sediments and suspended matter samples show relative LREE enrichment and HREE depletion. REEs are relatively enriched in fine-grained fractions of the sediments.exchangeable. About 65 to 85% of REEs in the particles exist in the residual form, and the exchangeable form is very low. High proportions of residual REEs reveal that REEs in sediments and suspended matter are controlled by their abundances in the earth's crust. Carbonate, Fe-Mn oxide and organic fractions of REEs in sediments account for 2.4-6.9%, 5.2-11.1%, and 7.3-14.0% of the total contents respectively. They are similar to those in the suspended matter. This shows that carbonates, Fe-Mn oxides and organic matter play important roles during the particle-water interaction processes. By normalization to shales, the 3 forms of REEs follow convex shapes according to atomic number with middle REE (Sm, Eu, and Tb) enrichment, while light REE and heavy REE are depleted. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  11. Asteroid impacts on terrestrial planets: the effects of super-Earths and the role of the ν6 resonance

    Science.gov (United States)

    Smallwood, Jeremy L.; Martin, Rebecca G.; Lepp, Stephen; Livio, Mario

    2018-01-01

    With N-body simulations of a planetary system with an asteroid belt, we investigate how the asteroid impact rate on the Earth is affected by the architecture of the planetary system. We find that the ν6 secular resonance plays an important role in the asteroid collision rate with the Earth. Compared to exoplanetary systems, the Solar system is somewhat special in its lack of a super-Earth mass planet in the inner Solar system. We therefore first consider the effects of the presence of a super-Earth in the terrestrial planet region. We find a significant effect for super-Earths with a mass of around 10 M⊕ and a separation greater than about 0.7 au. For a super-Earth which is interior to the Earth's orbit, the number of asteroids colliding with Earth increases the closer the super-Earth is to the Earth's orbit. This is the result of multiple secular resonance locations causing more asteroids to be perturbed on to Earth-crossing orbits. When the super-Earth is placed exterior to Earth's orbit, the collision rate decreases substantially because the ν6 resonance no longer exists in the asteroid belt region. We also find that changing the semimajor axis of Saturn leads to a significant decrease in the asteroid collision rate, though increasing its mass increases the collision rate. These results may have implications for the habitability of exoplanetary systems.

  12. CP violation and the matter-antimatter asymmetry of the Universe

    International Nuclear Information System (INIS)

    Hambye, T.

    2012-01-01

    In our everyday environment one observes only matter. That is quite a fortunate situation... Any sizeable presence of antimatter on Earth, from the enormous energy it would release through annihilation with matter, would prevent us talking about it. For the physicist this fact, at first sight obvious, is nevertheless a kind of surprise: antimatter, which is observed in cosmic rays, in radioactive decays of nuclei, which has been copiously produced and extensively studied in accelerators and which is nowadays currently used in hospitals, turns out to have pretty much the same properties as matter. Moreover, the fact that matter dominates appears to be a general property of our Universe: no evidence of large quantities of antimatter has been observed at any distance from us. Why would matter have taken the advantage on antimatter? In this short review we explain how, through a limited number of basic elements, one can find answers to this question. Matter and antimatter have, in fact, not exactly the same properties: from laboratory experiments CP conservation is known not to be a fundamental law of nature. (author)

  13. Hyperons in nuclear matter from SU(3) chiral effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Petschauer, S.; Kaiser, N. [Technische Universitaet Muenchen, Physik Department, Garching (Germany); Haidenbauer, J. [Institut fuer Kernphysik, Forschungszentrum Juelich, Institute for Advanced Simulation, Juelich Center for Hadron Physics, Juelich (Germany); Meissner, Ulf G. [Institut fuer Kernphysik, Forschungszentrum Juelich, Institute for Advanced Simulation, Juelich Center for Hadron Physics, Juelich (Germany); Universitaet Bonn, Helmholtz-Institut fuer Strahlen- und Kernphysik and Bethe Center for Theoretical Physics, Bonn (Germany); Weise, W. [Technische Universitaet Muenchen, Physik Department, Garching (Germany); Villa Tambosi, ECT, Villazzano (Trento) (Italy)

    2016-01-15

    Brueckner theory is used to investigate the properties of hyperons in nuclear matter. The hyperon-nucleon interaction is taken from chiral effective field theory at next-to-leading order with SU(3) symmetric low-energy constants. Furthermore, the underlying nucleon-nucleon interaction is also derived within chiral effective field theory. We present the single-particle potentials of Λ and Σ hyperons in symmetric and asymmetric nuclear matter computed with the continuous choice for intermediate spectra. The results are in good agreement with the empirical information. In particular, our calculation gives a repulsive Σ-nuclear potential and a weak Λ-nuclear spin-orbit force. (orig.)

  14. 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

  15. Application of Fenton process to remove organic matter and PCBs from waste (fuller's earth) contaminated with insulating oil.

    Science.gov (United States)

    da Silva, Milady Renata Apolinário; Rodrigues, Eduardo de Oliveira; Espanhol-Soares, Melina; Silva, Flavio Soares; Kondo, Márcia Matiko; Gimenes, Rossano

    2018-01-09

    Polychlorinated biphenyls (PCBs) are carcinogenic to humans and can be found in fuller's earth used for the treatment of used transformer oil. This work describes an optimization of the Fenton process for the removal of contaminants from fuller's earth. The effects of pH (2.5 and 4.0), [H 2 O 2 ] (1.47 and 2.07 mol L -1 ), and [Fe 2+ ] (1.7 and 40 mmol L -1 ) were studied. The Fenton process efficiency was monitored using the decreases in the chemical oxygen demand (COD) and the concentrations of oil and grease, total carbon (TC), PCBs, and H 2 O 2 . The fuller's earth contaminated with insulating oil presented 35% (w/w) of TC, 34% (w/w) of oil and grease, 297.0 g L -1 COD, and 64 mg of PCBs per kg. The material could therefore be considered a dangerous waste. After Fenton treatment, using a slurry mode, there was a removal of 55% of COD, 20% of oil and grease, and 20% of TC, achieved at pH 2.5 using 2.07 mol L -1 of H 2 O 2 and 40.0 mmol L -1 of Fe 2+ . No PCBs were detected in the samples after the Fenton treatment, even using smaller amounts of Fenton reagents (1.47 mol L -1 of H 2 O 2 , 1.7 mmol L -1 of Fe 2+ , pH 2.5). The results indicated that the treated fuller's earth was free from PCB residues and could be disposed of in a simple landfill, in accordance with Brazilian PCB regulations.

  16. Effect of electromagnetic dipole dark matter on energy transport in the solar interior

    Energy Technology Data Exchange (ETDEWEB)

    Geytenbeek, Ben; Rao, Soumya; White, Martin; Williams, Anthony G. [ARC Centre of Excellence for Particle Physics at the Terascale and CSSM, Department of Physics, University of Adelaide, Adelaide, South Australia 5005 (Australia); Scott, Pat; Vincent, Aaron C. [Department of Physics, Imperial College London, Blackett Laboratory, Prince Consort Road, London SW7 2AZ (United Kingdom); Serenelli, Aldo, E-mail: bg364@cam.ac.uk, E-mail: soumya.rao@ncbj.gov.pl, E-mail: p.scott@imperial.ac.uk, E-mail: aldos@ice.csic.es, E-mail: aaron.vincent@imperial.ac.uk, E-mail: martin.white@adelaide.edu.au, E-mail: anthony.williams@adelaide.edu.au [Institute of Space Sciences (IEEC-CSIC), Campus UAB, Carrer de Can Magrans s/n, 08193, Barcelona (Spain)

    2017-03-01

    In recent years, a revised set of solar abundances has led to a discrepancy in the sound-speed profile between helioseismology and theoretical solar models. Conventional solutions require additional mechanisms for energy transport within the Sun. Vincent et al. have recently suggested that dark matter with a momentum or velocity dependent cross section could provide a solution. In this work, we consider three models of dark matter with such cross sections and their effect on the stellar structure. In particular, the three models incorporate dark matter particles interacting through an electromagnetic dipole moment: an electric dipole, a magnetic dipole or an anapole. Each model is implemented in the DarkStec stellar evolution program, which incorporates the effects of dark matter capture and heat transport within the solar interior. We show that dark matter with an anapole moment of ∼ 1 GeV{sup −2} or magnetic dipole moment of ∼ 10{sup −3}μ {sub p} can improve the sound-speed profile, small frequency separations and convective zone radius with respect to the Standard Solar Model. However, the required dipole moments are strongly excluded by direct detection experiments.

  17. Invisible wombs: rethinking Paracelsus's concept of body and matter.

    Science.gov (United States)

    Daniel, Dane T

    2006-07-01

    Paracelsus's matter theory remains a puzzling subject, especially insofar as his division of matter and the human being is concerned. Paracelsus's early matter theory, as presented in perhaps his most significant chemical work, the Archidoxis, was influenced by John of Rupescissa and contained elements that the mature Paracelsus--greatly influenced by theological concerns and his own unique biblical exegesis--would abandon due to their nonconformity with scripture. The article stresses Paracelsus's interpretation of Genesis 2:7, and the author argues that the Paracelsus of the Astronomia Magna (1537-38)--somewhat echoing the theories in his so-called "meterological writings"--held that the cosmos and microcosm (man) consist of soul, sidereal body (also mortal spirit), elemental mortal matter (a combination of seeds and the tria prima of salt, sulfur, and mercury as produced in the four elemental mothers of air, earth, fire, and water), and eternal body (e.g. the resurrection body). The focus in this article is on mortal matter; Paracelsus's natural philosophy and theology become much more accessible when one understands this quadripartite division.

  18. Signals for invisible matter from solar-terrestrial observations

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    We observe a strong correlation between the orbital position of the planets with solar phenomena like flares or the variation of EUV irradiance. Similarly, a correlation is found in the study of the ionization content of the Earth atmosphere. Planetary gravitational lensing of one (or more) streams of slow moving invisible matter is proposed as an explanation of such a behaviour.

  19. CP violation and matter effect in long baseline neutrino oscillation experiments

    International Nuclear Information System (INIS)

    Arafune, J.; Koike, M.; Sato, J.

    1997-01-01

    We show simple methods of how to separate pure CP-violating effects from matter effects in long baseline neutrino oscillation experiments with three generations of neutrinos. We give compact formulas for neutrino oscillation probabilities assuming one of the three neutrino masses (presumably ν τ mass) to be much larger than the other masses and the effective mass due to the matter effect. Two methods are shown. One is to observe envelopes of the curves of oscillation probabilities as functions of neutrino energy; a merit of this method is that only a single detector is enough to determine the presence of CP violation. The other is to compare experiments with at least two different baseline lengths; this has the merit that it needs only a narrow energy range of oscillation data. copyright 1997 The American Physical Society

  20. High Energy Electron Signals from Dark Matter Annihilation in the Sun

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, Philip; /SLAC; Toro, Natalia; /Stanford U., ITP; Weiner, Neal; Yavin, Itay; /New York U., CCPP

    2012-04-09

    In this paper we discuss two mechanisms by which high energy electrons resulting from dark matter annihilations in or near the Sun can arrive at the Earth. Specifically, electrons can escape the sun if DM annihilates into long-lived states, or if dark matter scatters inelastically, which would leave a halo of dark matter outside of the sun. Such a localized source of electrons may affect the spectra observed by experiments with narrower fields of view oriented towards the sun, such as ATIC, differently from those with larger fields of view such as Fermi. We suggest a simple test of these possibilities with existing Fermi data that is more sensitive than limits from final state radiation. If observed, such a signal will constitute an unequivocal signature of dark matter.

  1. Astrophysical dark matter: candidates from particle physics and detection possibilities

    International Nuclear Information System (INIS)

    Freese, K.

    1989-01-01

    In this talk, I will discuss the arguments that 50% to 90% of the matter in galaxies, including our own, is made of an unknown type of dark matter. I will review the reason why cosmologists believe Ω = 1 and illustrate the contrast with the limits on the amount of baryonic matter from element abundances in Big Bang Nucleosynthesis. Other arguments for nonbaryonic dark matter will also be discussed. Candidates for the dark matter from particle physics will be presented. I will focus on cold dark matter candidates known as WIMPs, weakly interacting massive (O(GeV)) particles. I will try to illustrate why these particles are interesting for astrophysics and outline ideas for cornering them. Detection possibilities for these particles include indirect detection, which takes advantage of the annihilation products of these particles in the galactic halo, the sun, or the earth. Direct detection via newly proposed cryogenic detectors must be sensitive to <∼ keV energy deposits. Annual modulation of the dark matter signal can be used as a signature for these halo particles. I hope to motivate the interest in these particles and discuss ideas for finding them

  2. Co-Seismic Mass Displacement and its Effect on Earth's Rotation and Gravity

    Science.gov (United States)

    Chao, B. F.; Gross, R. S.

    2004-01-01

    Mantle processes often involve large-scale mass transport, ranging from mantle convection, tectonic motions, glacial isostatic adjustment, to tides, atmospheric and oceanic loadings, volcanism and seismicity. On very short time scale of less than an hour, co-seismic event, apart from the "shaking" that is the earthquake, leaves behind permanent (step-function-like) displacements in the crust and mantle. This redistribution of mass changes the Earth's inertia tensor (and hence Earth's rotation in both length-of-day and polar motion), and the gravity field. The question is whether these effects are large enough to be of any significance. In this paper we report updated calculation results based on Chao & Gross. The calculation uses the normal mode summation scheme, applied to over twenty thousand major earthquakes that occurred during 1976-2002, according to source mechanism solutions given by the Harvard Centroid Moment Tensor catalog. Compared to the truly large ones earlier in the century, the earthquakes we study are individually all too small to have left any discernible signature in geodetic records of Earth rotation or global gravity field. However, their collective effects continue to exhibit an extremely strong statistical tendencies, conspiring to decrease J2 and J22 while shortening LOD, resulting in a rounder and more compact Earth. Strong tendency is also seen in the earthquakes trying to "nudge" the Earth rotation pole towards approx. 140 deg.E, roughly opposite to the observed polar drift direction. Currently, the Gravity Recovery And Climate Experiment (GRACE) is measuring the time-variable gravity to high degree and order with unprecedented accuracy. Our results show that great earthquakes such as the 1960 Chilean or 1964 Alaskan events cause gravitational field changes that are large enough to be detected by GRACE.

  3. Effects of Mixed Alkaline Earth Oxides in Potash Silicate Glass ...

    African Journals Online (AJOL)

    The aim of this work is to investigate the effects of mixed alkaline earth oxide in potash silicate glasses with regards to their physical properties. More recently; there has been an increase in the demand for light weight glasses which retains their physical and chemical properties for both domestic and industrial applications.

  4. Electroweakly-interacting Dirac dark matter

    International Nuclear Information System (INIS)

    Nagata, Natsumi

    2014-11-01

    We consider a class of fermionic dark matter candidates that are charged under both the SU(2) L and U(1) Y gauge interactions. Such a dark matter is stringently restricted by the dark matter direct detection experiments, since the Z-boson exchange processes induce too large dark matter-nucleus elastic scattering cross sections. Effects of ultraviolet (UV) physics, however, split it into two Majorana fermions to evade the constraint. These effects may be probed by means of the dark matter-nucleus scattering via the Higgs-boson exchange process, as well as the electric dipole moments induced by the dark matter and its SU(2) L partner fields. In this Letter, we evaluate them with effective operators that describe the UV-physics effects. It turns out that the constraints coming from the experiments for the quantities have already restricted the dark matters with hypercharge Y≥3/2. Future experiments have sensitivities to probe this class of dark matter candidates, and may disfavor the Y≥1 cases if no signal is observed. In this case, only the Y=0 and 1/2 cases may be the remaining possibilities for the SU(2) L charged fermionic dark matter candidates.

  5. The association of coronal mass ejections with their effects near the Earth

    Directory of Open Access Journals (Sweden)

    R. Schwenn

    2005-03-01

    Full Text Available To this day, the prediction of space weather effects near the Earth suffers from a fundamental problem: The radial propagation speed of "halo" CMEs (i.e. CMEs pointed along the Sun-Earth-line that are known to be the main drivers of space weather disturbances towards the Earth cannot be measured directly because of the unfavorable geometry. From inspecting many limb CMEs observed by the LASCO coronagraphs on SOHO we found that there is usually a good correlation between the radial speed and the lateral expansion speed Vexp of CME clouds. This latter quantity can also be determined for earthward-pointed halo CMEs. Thus, Vexp may serve as a proxy for the otherwise inaccessible radial speed of halo CMEs. We studied this connection using data from both ends: solar data and interplanetary data obtained near the Earth, for a period from January 1997 to 15 April 2001. The data were primarily provided by the LASCO coronagraphs, plus additional information from the EIT instrument on SOHO. Solar wind data from the plasma instruments on the SOHO, ACE and Wind spacecraft were used to identify the arrivals of ICME signatures. Here, we use "ICME" as a generic term for all CME effects in interplanetary space, thus comprising not only ejecta themselves but also shocks as well. Among 181 front side or limb full or partial halo CMEs recorded by LASCO, on the one hand, and 187 ICME events registered near the Earth, on the other hand, we found 91 cases where CMEs were uniquely associated with ICME signatures in front of the Earth. Eighty ICMEs were associated with a shock, and for 75 of them both the halo expansion speed Vexp and the travel time Ttr of the shock could be determined. The function Ttr=203-20.77*ln (Vexp fits the data best. This empirical formula can be used for predicting further ICME arrivals, with a 95% error margin of about one day. Note, though, that in 15% of comparable cases, a

  6. Quantifying and Comparing Effects of Climate Engineering Methods on the Earth System

    Science.gov (United States)

    Sonntag, Sebastian; Ferrer González, Miriam; Ilyina, Tatiana; Kracher, Daniela; Nabel, Julia E. M. S.; Niemeier, Ulrike; Pongratz, Julia; Reick, Christian H.; Schmidt, Hauke

    2018-02-01

    To contribute to a quantitative comparison of climate engineering (CE) methods, we assess atmosphere-, ocean-, and land-based CE measures with respect to Earth system effects consistently within one comprehensive model. We use the Max Planck Institute Earth System Model (MPI-ESM) with prognostic carbon cycle to compare solar radiation management (SRM) by stratospheric sulfur injection and two carbon dioxide removal methods: afforestation and ocean alkalinization. The CE model experiments are designed to offset the effect of fossil-fuel burning on global mean surface air temperature under the RCP8.5 scenario to follow or get closer to the RCP4.5 scenario. Our results show the importance of feedbacks in the CE effects. For example, as a response to SRM the land carbon uptake is enhanced by 92 Gt by the year 2100 compared to the reference RCP8.5 scenario due to reduced soil respiration thus reducing atmospheric CO2. Furthermore, we show that normalizations allow for a better comparability of different CE methods. For example, we find that due to compensating processes such as biogeophysical effects of afforestation more carbon needs to be removed from the atmosphere by afforestation than by alkalinization to reach the same global warming reduction. Overall, we illustrate how different CE methods affect the components of the Earth system; we identify challenges arising in a CE comparison, and thereby contribute to developing a framework for a comparative assessment of CE.

  7. EFFECTS OF THE NEUTRINO MASS SPLITTING ON THE NONLINEAR MATTER POWER SPECTRUM

    International Nuclear Information System (INIS)

    Wagner, Christian; Verde, Licia; Jimenez, Raul

    2012-01-01

    We have performed cosmological N-body simulations which include the effect of the masses of the individual neutrino species. The simulations were aimed at studying the effect of different neutrino hierarchies on the matter power spectrum. Compared to the linear theory predictions, we find that nonlinearities enhance the effect of hierarchy on the matter power spectrum at mildly nonlinear scales. The maximum difference between the different hierarchies is about 0.5% for a sum of neutrino masses of 0.1 eV. Albeit this is a small effect, it is potentially measurable from upcoming surveys. In combination with neutrinoless double-β decay experiments, this opens up the possibility of using the sky to determine if neutrinos are Majorana or Dirac fermions.

  8. The effect of the scalar-isovector meson field on hyperon-rich neutron star matter

    International Nuclear Information System (INIS)

    Mi, Aijun; Zuo, Wei; Li, Ang

    2008-01-01

    We investigate the effect of the scalar-isovector δ-meson field on the equation of state (EOS) and composition of hyperonic neutron star matter, and the properties of hyperonic neutron stars within the framework of the relativistic mean field theory. The influence of the δ-field turns out to be quite different and generally weaker for hyperonic neutron star matter as compared to that for npeμ neutron star matter. We find that inclusion of the δ-field enhances the strangeness content slightly and consequently moderately softens the EOS of neutron star matter in its hyperonic phase. As for the composition of hyperonic star matter, the effect of the δ-field is shown to shift the onset of the negatively-charged (positively-charged) hyperons to slightly lower (higher) densities and to enhance (reduce) their abundances. The influence of the δ-field on the maximum mass of hyperonic neutron stars is found to be fairly weak, whereas inclusion of the δ-field turns out to enhance sizably both the radii and the moments of inertia of neutron stars with given masses. It is also shown that the effects of the δ-field on the properties of hyperonic neutron stars remain similar in the case of switching off the Σ hyperons. (author)

  9. Building a Dashboard of the Planet with Google Earth and Earth Engine

    Science.gov (United States)

    Moore, R. T.; Hancher, M.

    2016-12-01

    In 2005 Google Earth, a popular 3-D virtual globe, was first released. Scientists immediately recognized how it could be used to tell stories about the Earth. From 2006 to 2009, the "Virtual Globes" sessions of AGU included innovative examples of scientists and educators using Google Earth, and since that time it has become a commonplace tool for communicating scientific results. In 2009 Google Earth Engine, a cloud-based platform for planetary-scale geospatial analysis, was first announced. Earth Engine was initially used to extract information about the world's forests from raw Landsat data. Since then, the platform has proven highly effective for general analysis of georeferenced data, and users have expanded the list of use cases to include high-impact societal issues such as conservation, drought, disease, food security, water management, climate change and environmental monitoring. To support these use cases, the platform has continuously evolved with new datasets, analysis functions, and user interface tools. This talk will give an overview of the latest Google Earth and Earth Engine functionality that allow partners to understand, monitor and tell stories about of our living, breathing Earth. https://earth.google.com https://earthengine.google.com

  10. A magnetic filter with permanent magnets on the basis of rare earths

    Czech Academy of Sciences Publication Activity Database

    Žežulka, Václav; Straka, Pavel; Mucha, Pavel

    2004-01-01

    Roč. 268, - (2004), s. 219-226 ISSN 0304-8853 R&D Projects: GA AV ČR IBS3046004 Institutional research plan: CEZ:AV0Z3046908 Keywords : magnetic filtration * rare earth magnets * high gradient magnetic Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.031, year: 2004

  11. Matter-wave bright solitons in effective bichromatic lattice potentials

    Indian Academy of Sciences (India)

    Matter-wave bright solitons in bichromatic lattice potentials are considered and their dynamics for different lattice environments are studied. Bichromatic potentials are created from superpositions of (i) two linear optical lattices and (ii) a linear and a nonlinear optical lattice. Effective potentials are found for the solitons in both ...

  12. The effects of puberty on white matter development in boys.

    Science.gov (United States)

    Menzies, Lara; Goddings, Anne-Lise; Whitaker, Kirstie J; Blakemore, Sarah-Jayne; Viner, Russell M

    2015-02-01

    Neuroimaging studies demonstrate considerable changes in white matter volume and microstructure during adolescence. Most studies have focused on age-related effects, whilst puberty-related changes are not well understood. Using diffusion tensor imaging and tract-based spatial statistics, we investigated the effects of pubertal status on white matter mean diffusivity (MD) and fractional anisotropy (FA) in 61 males aged 12.7-16.0 years. Participants were grouped into early-mid puberty (≤Tanner Stage 3 in pubic hair and gonadal development; n=22) and late-post puberty (≥Tanner Stage 4 in pubic hair or gonadal development; n=39). Salivary levels of pubertal hormones (testosterone, DHEA and oestradiol) were also measured. Pubertal stage was significantly related to MD in diverse white matter regions. No relationship was observed between pubertal status and FA. Regression modelling of MD in the significant regions demonstrated that an interaction model incorporating puberty, age and puberty×age best explained our findings. In addition, testosterone was correlated with MD in these pubertally significant regions. No relationship was observed between oestradiol or DHEA and MD. In conclusion, pubertal status was significantly related to MD, but not FA, and this relationship cannot be explained by changes in chronological age alone. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. NASA Earthdata Forums: An Interactive Venue for Discussions of NASA Data and Earth Science

    Science.gov (United States)

    Hearty, Thomas J., III; Acker, James; Meyer, Dave; Northup, Emily A.; Bagwell, Ross E.

    2017-01-01

    We demonstrate how students and teachers can register to use the NASA Earthdata Forums. The NASA Earthdata forums provide a venue where registered users can pose questions regarding NASA Earth science data in a moderated forum, and have their questions answered by data experts and scientific subject matter experts connected with NASA Earth science missions and projects. Since the forums are also available for research scientists to pose questions and discuss pertinent topics, the NASA Earthdata Forums provide a unique opportunity for students and teachers to gain insight from expert scientists and enhance their knowledge of the many different ways that NASA Earth observations can be used in research and applications.

  14. Dark Matter Caustics

    International Nuclear Information System (INIS)

    Natarajan, Aravind

    2010-01-01

    The continuous infall of dark matter with low velocity dispersion in galactic halos leads to the formation of high density structures called caustics. Dark matter caustics are of two kinds : outer and inner. Outer caustics are thin spherical shells surrounding galaxies while inner caustics have a more complicated structure that depends on the dark matter angular momentum distribution. The presence of a dark matter caustic in the plane of the galaxy modifies the gas density in its neighborhood which may lead to observable effects. Caustics are also relevant to direct and indirect dark matter searches.

  15. The Earth is a Planet Too!

    Science.gov (United States)

    Cairns, Brian

    2014-01-01

    When the solar system formed, the sun was 30 dimmer than today and Venus had an ocean. As the sun brightened, a runaway greenhouse effect caused the Venus ocean to boil away. At times when Earth was younger, the sun less bright, and atmospheric CO2 less, Earth froze over (snowball Earth). Earth is in the sweet spot today. Venus is closer to sun than Earth is, but cloud-covered Venus absorbs only 25 of incident sunlight, while Earth absorbs 70. Venus is warmer because it has a thick carbon dioxide atmosphere causing a greenhouse effect of several hundred degrees. Earth is Goldilocks choice among the planets, the one that is just right for life to exist. Not too hot. Not too cold. How does the Earth manage to stay in this habitable range? Is there a Gaia phenomenon keeping the climate in bounds? A nice idea, but it doesnt work. Today, greenhouse gas levels are unprecedented compared to the last 450,000 years.

  16. Dirac matter

    CERN Document Server

    Rivasseau, Vincent; Fuchs, Jean-Nöel

    2017-01-01

    This fifteenth volume of the Poincare Seminar Series, Dirac Matter, describes the surprising resurgence, as a low-energy effective theory of conducting electrons in many condensed matter systems, including graphene and topological insulators, of the famous equation originally invented by P.A.M. Dirac for relativistic quantum mechanics. In five highly pedagogical articles, as befits their origin in lectures to a broad scientific audience, this book explains why Dirac matters. Highlights include the detailed "Graphene and Relativistic Quantum Physics", written by the experimental pioneer, Philip Kim, and devoted to graphene, a form of carbon crystallized in a two-dimensional hexagonal lattice, from its discovery in 2004-2005 by the future Nobel prize winners Kostya Novoselov and Andre Geim to the so-called relativistic quantum Hall effect; the review entitled "Dirac Fermions in Condensed Matter and Beyond", written by two prominent theoreticians, Mark Goerbig and Gilles Montambaux, who consider many other mater...

  17. Dark matter as a trigger for periodic comet impacts.

    Science.gov (United States)

    Randall, Lisa; Reece, Matthew

    2014-04-25

    Although statistical evidence is not overwhelming, possible support for an approximately 35×106  yr periodicity in the crater record on Earth could indicate a nonrandom underlying enhancement of meteorite impacts at regular intervals. A proposed explanation in terms of tidal effects on Oort cloud comet perturbations as the Solar System passes through the galactic midplane is hampered by lack of an underlying cause for sufficiently enhanced gravitational effects over a sufficiently short time interval and by the time frame between such possible enhancements. We show that a smooth dark disk in the galactic midplane would address both these issues and create a periodic enhancement of the sort that has potentially been observed. Such a disk is motivated by a novel dark matter component with dissipative cooling that we considered in earlier work. We show how to evaluate the statistical evidence for periodicity by input of appropriate measured priors from the galactic model, justifying or ruling out periodic cratering with more confidence than by evaluating the data without an underlying model. We find that, marginalizing over astrophysical uncertainties, the likelihood ratio for such a model relative to one with a constant cratering rate is 3.0, which moderately favors the dark disk model. Our analysis furthermore yields a posterior distribution that, based on current crater data, singles out a dark matter disk surface density of approximately 10M⊙/pc2. The geological record thereby motivates a particular model of dark matter that will be probed in the near future.

  18. The effects of increased phosphorus application on shoot dry matter ...

    African Journals Online (AJOL)

    The effects of increased phosphorus application on shoot dry matter, shoot P and Zn concentrations in wheat ( Triticum durum L.) and maize ( Zea mays L.)wheat ( Triticum durum L.) and maize ( Zea mays L.) grown in a calcareous soil.

  19. Isotopes in the earth sciences

    Energy Technology Data Exchange (ETDEWEB)

    Bowen, Robert

    1988-01-01

    This book examines significant aspects of isotope applications in geology and geochemistry commencing with basic matters, such as atomic structure, stable nuclides and their fractionation, as well as the various decay modes of unstable nuclides. Modern mass spectrometry techniques including electrostatic tandem accelerators are followed by a review of radioisotope dating technology. The relatively new method using the rare earth elements samarium and neodymium are covered. Other geochronometers, applicable to both rocks and minerals not dateable otherwise, are included. A review is given of isotopes in the atmosphere, hydrosphere and lithosphere of the Earth. Those of oxygen and hydrogen together with the cosmogenic radionuclides tritium and radiocarbon are discussed in relation to the biosphere. The role of isotopes of carbon, nitrogen and sulphur is described and extended to fossil fuels and rocks as well as meteorites. Related themes such as Phanerozoic oceans, oceanic palaeothermometry, snow and ice stratigraphy and geothermal waters are covered. The field of isotopic palaeoecology is discussed. Radioactive wastes, their accumulation, dangers and disposal are investigated with especial reference to their environmental impacts.

  20. The Pale Orange Dot: Spectral Effects of a Hazy Early Earth

    Science.gov (United States)

    Arney, G. N.; Meadows, V. S.; Domagal-Goldman, S. D.; Claire, M.; Schwieterman, E.

    2014-12-01

    Increasing evidence suggests Archean Earth had a photochemical hydrocarbon haze similar to Titan's (Zerkle et al. 2012), with important climate implications (Pavlov et al. 2001, Trainer et al. 2006, Haqq-Misra et al. 2008, Domagal-Goldman et al. 2008, Wolf and Toon 2012). Observations also suggest hazy exoplanets are common (Sing et al. 2011, Kreidberg et al 2014), so hazy planet spectra will be relevant to future exoplanet spectral characterization missions. Here, we consider the implications of hydrocarbon aerosols on the spectrum of Archean Earth, examining the effect of a haze layer on the detectability of spectral features from putative biosignatures and the Rayleigh scattering slope. We also examine haze's impact on the spectral energy distribution at the planetary surface, which may be important to the co-evolution of life with its environment. Because the atmospheric pressure and haze particle composition of the Archean Earth are poorly constrained, we test the impact of atmospheric pressure and particle density on haze formation. Our study uses a modified version of the 1-D photochemical code developed originally by Kasting et al. (1979) to generate a fractal haze in the model Archean atmosphere. The 1-D line-by-line fully multiple scattering Spectral Mapping Atmospheric Radiative Transfer Model (SMART) (Meadows and Crisp 1996) is then used to generate synthetic spectra of early Earth with haze. We find (Fig 1) that haze scattering significantly depletes the radiation at short wavelengths, strongly affecting the spectral region of the Rayleigh slope, a broadband change in spectral shape detectable at low spectral resolution. At the surface, the spectral energy distribution is shifted towards longer wavelengths, which may be important to photosynthetic life. Thus, the haze may have significant effects on biology, which in turn produces the methane that leads to haze formation, creating feedback loops between biology and the planet.

  1. Preparing Earth Data Scientists for 'the sexiest job of the 21st century'

    Science.gov (United States)

    Kempler, S. J.

    2014-12-01

    What Exactly do Earth Data Scientists do, and What do They Need to Know, to do It? There is not one simple answer, but there are many complex answers. Data Science, and data analytics, are new and nebulas, and takes on different characteristics depending on: The subject matter being analyzed, the maturity of the research, and whether the employed subject specific analytics is descriptive, diagnostic, discoveritive, predictive, or prescriptive, in nature. In addition, in a, thus far, business driven paradigm shift, university curriculums teaching data analytics pertaining to Earth science have, as a whole, lagged behind, and/or have varied in approach. This presentation attempts to breakdown and identify the many activities that Earth Data Scientists, as a profession, encounter, as well as provide case studies of specific Earth Data Scientist and data analytics efforts. I will also address the educational preparation, that best equips future Earth Data Scientists, needed to further Earth science heterogeneous data research and applications analysis. The goal of this presentation is to describe the actual need for Earth Data Scientists and the practical skills to perform Earth science data analytics, thus hoping to initiate discussion addressing a baseline set of needed expertise for educating future Earth Data Scientists.

  2. Preparing Earth Data Scientists for 'The Sexiest Job of the 21st Century'

    Science.gov (United States)

    Kempler, Steven

    2014-01-01

    What Exactly do Earth Data Scientists do, and What do They Need to Know, to do It? There is not one simple answer, but there are many complex answers. Data Science, and data analytics, are new and nebulas, and takes on different characteristics depending on: The subject matter being analyzed, the maturity of the research, and whether the employed subject specific analytics is descriptive, diagnostic, discoveritive, predictive, or prescriptive, in nature. In addition, in a, thus far, business driven paradigm shift, university curriculums teaching data analytics pertaining to Earth science have, as a whole, lagged behind, andor have varied in approach.This presentation attempts to breakdown and identify the many activities that Earth Data Scientists, as a profession, encounter, as well as provide case studies of specific Earth Data Scientist and data analytics efforts. I will also address the educational preparation, that best equips future Earth Data Scientists, needed to further Earth science heterogeneous data research and applications analysis. The goal of this presentation is to describe the actual need for Earth Data Scientists and the practical skills to perform Earth science data analytics, thus hoping to initiate discussion addressing a baseline set of needed expertise for educating future Earth Data Scientists.

  3. Effective pion--nucleon interaction in nuclear matter

    International Nuclear Information System (INIS)

    Celenza, L.S.; Liu, L.C.; Nutt, W.; Shakin, C.M.

    1976-01-01

    We discuss the modification of the interaction between a pion and a nucleon in the presence of an infinite medium of nucleons (nuclear matter). The theory presented here is covariant and is relevant to the calculation of the pion--nucleus optical potential. The specific effects considered are the modifications of the nucleon propagator due to the Pauli principle and the modification of the pion and nucleon propagators due to collisions with nucleons of the medium. We also discuss in detail the pion self-energy in the medium, paying close attention to off-shell effects. These latter effects are particularly important because of the rapid variation with energy of the fundamental pion--nucleon interaction. Numerical results are presented, the main feature being the appearance of a significant damping width for the (3, 3) resonance

  4. The God Machine seeks the origin of the matter

    International Nuclear Information System (INIS)

    Martin, R.

    2015-01-01

    Under the green fields of the French-Swiss border, not far from the Alps and Lake Geneva, is hidden underground most strength Earth energy. The generated particles of low mass, subatomic, ue collide with each other in a huge circumference of 27 kilometers, the Large Hadron Collider (LHC English siglasen), an underground infrastructure that seeks to answer big questions of science: the origin of matter we know or dark matter and energy, which together occupy 95% of the universe and that we are not able to see or understand. They call it the 'god machine' and is the largest and most complex built in the world. (Author)

  5. Effect of rare earth metal on the spin-orbit torque in magnetic heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Ueda, Kohei; Pai, Chi-Feng; Tan, Aik Jun; Mann, Maxwell; Beach, Geoffrey S. D., E-mail: gbeach@mit.edu [Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

    2016-06-06

    We report the effect of the rare earth metal Gd on current-induced spin-orbit torques (SOTs) in perpendicularly magnetized Pt/Co/Gd heterostructures, characterized using harmonic measurements and spin-torque ferromagnetic resonance (ST-FMR). By varying the Gd metal layer thickness from 0 nm to 8 nm, harmonic measurements reveal a significant enhancement of the effective fields generated from the Slonczewski-like and field-like torques. ST-FMR measurements confirm an enhanced effective spin Hall angle and show a corresponding increase in the magnetic damping constant with increasing Gd thickness. These results suggest that Gd plays an active role in generating SOTs in these heterostructures. Our finding may lead to spin-orbitronics device application such as non-volatile magnetic random access memory, based on rare earth metals.

  6. Low earth orbit environmental effects on the space station photovoltaic power generation systems

    International Nuclear Information System (INIS)

    Nahra, H.K.

    1977-01-01

    A summary of the Low Earth Orbital Environment, its impact on the photovoltaic power systems of the space station and the solutions implemented to resolve the environmental concerns or issues are described. Low Earth Orbital Environment (LEO) presents several concerns to the photovoltaic power systems of the space station. These concerns include atomic oxygen interaction with the polymeric substrate of the solar arrays, ionized environment effects on the array operating voltage, the effects of the meteoroids and debris impacts and penetration through the different layers of the solar cells and their circuits, and the high energy particle and radiation effects on the overall solar array performance. Potential solutions to some of the degrading environmental interactions that will provide the photovoltaic power system of the space station with the desired life are also summarized

  7. Determination of trace amounts of rare earth elements in various environmental samples by spark source mass spectrography

    International Nuclear Information System (INIS)

    Sugimae, Akiyoshi

    1978-01-01

    A chemical concentration-mass spectrographic procedure was described for the determination of trace amounts of rare earth elements in various environmental samples: airborne particulate matter, dustfall, soil and so forth. A 0.5 to 1 gram of sample material was decomposed by fusion with sodium carbonate. The silica dehydrated in the usual way was filtered off and the filtrate from the silica was then treated with ammonium hydroxide to precipitate the rare earth elements. After ignition of the precipitate, two ml of internal standard solution containing 20 μg/ml of silver were added and the mixture was then evaporated to dryness. The residue was mixed with an equal amount of graphite powder and then pressed into electrodes. Relative sensitivity coefficients (Ag=1.0) were determined by using Spex Mix and U. S. Geological Survey rock standard G-2. U. S. Geological Survey rock standard GSP-1 and N.B.S. coal fly ash SRM 1633 were analysed to evaluate the accuracy of the proposed method. Comparison of the mass spectral values with literature ones indicated a good agreement. The coefficient of variation obtained by replicate analysis of SRM 1633 was better than 25%. The proposed method was applied to the determination of rare earth elements in airborne particulate matter and dustfall collected on polystyrene filter and in dustjars, respectively. Results for the rare earth elements in the blank of glass fiber filter which was widely used for the collection of airborne particulate matter were also presented. (auth.)

  8. 40 CFR 49.126 - Rule for limiting fugitive particulate matter emissions.

    Science.gov (United States)

    2010-07-01

    ... amount of fugitive particulate matter that may be emitted from certain air pollution sources operating... minimize the accumulation of dusty materials that have the potential to become airborne, and the prompt... materials likely to become airborne. (viii) The prompt removal from paved streets of earth or other material...

  9. Rare earth elements and oxides in liquid phase epitaxy

    Czech Academy of Sciences Publication Activity Database

    Procházková, Olga; Grym, Jan; Zavadil, Jiří; Kopecká, M.

    2006-01-01

    Roč. 100, č. 8 (2006), s. 640-- ISSN 0009-2770. [Sjezd chemických společností /58./. Ústí nad Labem, 04.09.2006-08.09.2006] R&D Projects: GA ČR(CZ) GA102/06/0153 Institutional research plan: CEZ:AV0Z20670512 Keywords : semiconductor technology * rare earth metals Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.431, year: 2006

  10. Effective wave tilt and surface impedance over a laterally inhomogeneous two-layer earth

    International Nuclear Information System (INIS)

    Hughes, W.J.; Wait, J.R.

    1975-01-01

    Using a perturbation method, the effect of a simple two-dimensional model on the electromagnetic fields at the surface of the Earth is considered for a postulated downcoming plane wave. The calculated change in the surface impedance and wave tilt due to lateral inhomogeneities is examined. It is found that the magnetic wave tilt (H/sub z//H/sub x/) is most seriously affected by such anomalies. This may have important consequences on electromagnetic probing of nonuniform portions of the Earth's crust

  11. Quasi-particles and effective mean field in strongly interacting matter

    International Nuclear Information System (INIS)

    Levai, P.; Ko, C.M.

    2010-01-01

    We introduce a quasi-particle model of strongly interacting quark-gluon matter and explore the possible connection to an effective field theoretical description consisting of a scalar σ field by introducing a dynamically generated mass, M(σ), and a self-consistently determined interaction term, B(σ). We display a possible connection between the two types of effective description, using the Friedberg-Lee model.

  12. Climatic effects during passage of the solar system through interstellar clouds

    International Nuclear Information System (INIS)

    Talbot, R.J. Jr.; Butler, D.M.; Newman, M.J.

    1976-01-01

    It is thought likely that the solar system passes through regions where there are a large number of dense interstellar clouds. When this occurs several processes may cause significant changes in the climate of the Earth and other planets. Matters here discussed include the influences of compression of the solar wind cavity, accretion of matter by the Sun, and particulate input into the Earth's atmosphere. Gravitational energy released by the accretion of interstellar material by the Sun may enhance the solar luminosity, and considerations of terrestrial heat balance suggest that luminosity enhancements of 1% or more will produce significant variations of climate. Observational evidence suggests that there is some mechanism producing a relationship between solar wind flow and climate. One proposed mechanism is that contemporary solar wind modulation of galactic cosmic rays influences climate, and the fact that the Earth would be outside the solar wind cavity for all or part of the year may have an effect on terrestrial climate. Relatively small variations of solar UV radiation input may have perceptible influences on climate, and if a 1% variation in radiation input to the stratosphere has a significant effect then accretion may have a large impact on terrestrial conditions, even though the change in the total heat balance is negligible.With regard to dust input into the Earth's atmosphere it is estimated that during the lifetime of the solar system the mass of dust grains accreted by the Earth should have been about 10 16 to 10 18 g; the matter of evidence for their presence is discussed. It is concluded that the processes proposed have very complex implications for global weather patterns; and at present it is not possible to evaluate which, if any, will unquestionably affect the Earth's climate. (U.K.)

  13. Boundary effects and gapped dispersion in rotating fermionic matter

    Directory of Open Access Journals (Sweden)

    Shu Ebihara

    2017-01-01

    Full Text Available We discuss the importance of boundary effects on fermionic matter in a rotating frame. By explicit calculations at zero temperature we show that the scalar condensate of fermion and anti-fermion cannot be modified by the rotation once the boundary condition is properly implemented. The situation is qualitatively changed at finite temperature and/or in the presence of a sufficiently strong magnetic field that supersedes the boundary effects. Therefore, to establish an interpretation of the rotation as an effective chemical potential, it is crucial to consider further environmental effects such as the finite temperature and magnetic field.

  14. The Effect of Phase-to-earth Faults on the Operating Conditions of a Separated 110 kV Grid Normally Operated with Effectively Earthed Neutral, and Temporarily Supplied from a Compensated 110 kV Grid

    Directory of Open Access Journals (Sweden)

    Wilhelm Rojewski

    2015-06-01

    Full Text Available The paper discusses the interoperability of the German compensated 110 kV grid and the Polish effectively earthed 110 kV grid. It is assumed that an area of one grid, separated from its power system, will be temporarily supplied from the other grid in its normal regime. Reference is made to the risks associated with phase-to-earth faults in grids so interconnected. Particular attention is paid to the working conditions of surge arresters and voltage transformers in the Polish 110 kV grid deprived of its neutral earthing when supplied from the German grid.

  15. Earth Science Enterprise Technology Strategy

    Science.gov (United States)

    1999-01-01

    NASA's Earth Science Enterprise (ESE) is dedicated to understanding the total Earth system and the effects of natural and human-induced changes on the global environment. The goals of ESE are: (1) Expand scientific knowledge of the Earth system using NASA's unique vantage points of space, aircraft, and in situ platforms; (2) Disseminate information about the Earth system; and (3) Enable the productive use of ESE science and technology in the public and private sectors. ESE has embraced the NASA Administrator's better, faster, cheaper paradigm for Earth observing missions. We are committed to launch the next generation of Earth Observing System (EOS) missions at a substantially lower cost than the EOS first series. Strategic investment in advanced instrument, spacecraft, and information system technologies is essential to accomplishing ESE's research goals in the coming decades. Advanced technology will play a major role in shaping the ESE fundamental and applied research program of the future. ESE has established an Earth science technology development program with the following objectives: (1) To accomplish ESE space-based and land-based program elements effectively and efficiently; and (2) To enable ESE's fundamental and applied research programs goals as stated in the NASA Strategic Plan.

  16. Main effects of the Earth's rotation on the stationary states of ultra-cold neutrons

    International Nuclear Information System (INIS)

    Arminjon, Mayeul

    2008-01-01

    The relativistic corrections in the Hamiltonian for a particle in a uniformly rotating frame are discussed. They are shown to be negligible in the case of ultra-cold neutrons (UCN) in the Earth's gravity. The effect, on the energy levels of UCN, of the main term due to the Earth's rotation, i.e. the angular-momentum term, is calculated. The energy shift is found proportional to the energy level itself

  17. Effect of Earth Ground and Environment on Body-Centric Communications in the MHz Band

    Directory of Open Access Journals (Sweden)

    Katsuyuki Fujii

    2012-01-01

    Full Text Available Body area network (BAN research, which uses the human body as a transmission channel, has recently attracted considerable attention globally. Zimmerman first advocated the idea in 1995. Illustrations of the electric field streamlines around the human body and wearable devices with electrodes were drawn. In the pictures, the electrodes of the wearable devices constitute a closed circuit with the human body and the earth ground. However, analysis of the circuit has not been conducted. In this study, we model the human body shunted to earth ground in a radio anechoic chamber to analyze the electric field strength around it and clarify the effect of earth ground during BAN run time. The results suggest that earth ground has little influence on the human body and wearable devices. Only when the human body is directly grounded, the electric field near the feet area will decrease. The input impedance of the transmitter is approximately the same, and the received open-circuit voltage and current of the receiver are also the same. In addition, we elucidate that stable communications can be established by developing a closed circuit using earth ground as return path. When the external electronic devices and human body are shunted to earth ground, the received open-circuit voltage and current increase.

  18. Detection of magnetized quark-nuggets, a candidate for dark matter.

    Science.gov (United States)

    VanDevender, J Pace; VanDevender, Aaron P; Sloan, T; Swaim, Criss; Wilson, Peter; Schmitt, Robert G; Zakirov, Rinat; Blum, Josh; Cross, James L; McGinley, Niall

    2017-08-18

    Quark nuggets are theoretical objects composed of approximately equal numbers of up, down, and strange quarks and are also called strangelets and nuclearites. They have been proposed as a candidate for dark matter, which constitutes ~85% of the universe's mass and which has been a mystery for decades. Previous efforts to detect quark nuggets assumed that the nuclear-density core interacts directly with the surrounding matter so the stopping power is minimal. Tatsumi found that quark nuggets could well exist as a ferromagnetic liquid with a ~10 12 -T magnetic field. We find that the magnetic field produces a magnetopause with surrounding plasma, as the earth's magnetic field produces a magnetopause with the solar wind, and substantially increases their energy deposition rate in matter. We use the magnetopause model to compute the energy deposition as a function of quark-nugget mass and to analyze testing the quark-nugget hypothesis for dark matter by observations in air, water, and land. We conclude the water option is most promising.

  19. The Effects of Meditation on Grey Matter Atrophy and Neurodegeneration: A Systematic Review.

    Science.gov (United States)

    Last, Nicole; Tufts, Emily; Auger, Leslie E

    2017-01-01

    The present systematic review is based on the premise that a variety of neurodegenerative diseases are accompanied by grey matter atrophy in the brain and meditation may impact this. Given that age is a major risk factor for many of these progressive and neurodegenerative diseases and that the percentage of the population over the age of 65 is quickly increasing, there is an obvious need for prompt treatment and prevention advances in research. As there is currently no cure for Alzheimer's disease and other neurodegenerative diseases, many are seeking non-pharmacological treatment options in attempts to offset the disease-related cognitive and functional declines. On the basis of a growing body of research suggesting that meditation is effective in increasing grey matter volume in healthy participants, this paper systematically reviewed the literature regarding the effects of meditation on restoring grey matter volume in healthy individuals and those affected by neurodegeneration. This review searched PubMed, CINAHL, and APA PsycNET to identify original studies that included MRI imaging to measure grey matter volume in meditators and post-mindfulness-based intervention participants compared to controls. Thirteen studies were considered eligible for review and involved a wide variety of meditation techniques and included participants with and without cognitive impairment. All studies reported significant increases in grey matter volume in the meditators/intervention group, albeit in assorted regions of the brain. Limited research exists on the mechanisms through which meditation affects disease-related neurodegeneration, but preliminary evidence suggests that it may offset grey matter atrophy.

  20. Baryonic matter and beyond

    OpenAIRE

    Fukushima, Kenji

    2014-01-01

    We summarize recent developments in identifying the ground state of dense baryonic matter and beyond. The topics include deconfinement from baryonic matter to quark matter, a diquark mixture, topological effect coupled with chirality and density, and inhomogeneous chiral condensates.

  1. Dark matter as a dynamic effect due to a non-minimal gravitational coupling with matter (I): Analytical results

    International Nuclear Information System (INIS)

    Bertolami, O; Paramos, J

    2010-01-01

    In this work the phenomenology of models possessing a non-minimal coupling between matter and geometry is discussed, with a particular focus on the possibility of describing the flattening of the galactic rotation curves as a dynamically generated effect derived from this modification to General Relativity. Two possibilities are discussed: firstly, that the observed discrepancy between the measured rotation velocity and the classical prediction is due to a deviation from geodesic motion, due to a non-(covariant) conservation of the energy-momentum tensor; secondly, that even if the principle of energy conservation holds, the dynamical effects arising due to the non-trivial terms in the Einstein equations of motion can give rise to an extra density contribution that may be interpreted as dark matter. In this work, The mechanism of the latter alternative is detailed; a numerical session ascertaining the order of magnitude of the relevant parameters is undertaken in another contribution to this volume, with possible cosmological implications discussed.

  2. Studying the physical basis of global warming: thermal effects of the interaction between radiation and matter and greenhouse effect

    Energy Technology Data Exchange (ETDEWEB)

    Besson, Ugo; De Ambrosis, Anna; Mascheretti, Paolo [Department of Physics ' A Volta' , University of Pavia, Via A Bassi 6, 27100 Pavia (Italy)], E-mail: ugo.besson@unipv.it, E-mail: anna.deambrosisvigna@unipv.it

    2010-03-15

    We present a teaching module dealing with the thermal effects of interaction between radiation and matter, the infrared emission of bodies and the greenhouse effect devoted to university level and teacher education. The module stresses the dependence of the optical properties of materials (transparency, absorptivity and emissivity) on radiation frequency, as a result of interaction between matter and radiation. Multiple experiences are suggested to favour a progressive construction of knowledge on the physical aspects necessary to understand the greenhouse effect and global warming. Some results obtained with university students are briefly reported.

  3. Studying the physical basis of global warming: thermal effects of the interaction between radiation and matter and greenhouse effect

    International Nuclear Information System (INIS)

    Besson, Ugo; De Ambrosis, Anna; Mascheretti, Paolo

    2010-01-01

    We present a teaching module dealing with the thermal effects of interaction between radiation and matter, the infrared emission of bodies and the greenhouse effect devoted to university level and teacher education. The module stresses the dependence of the optical properties of materials (transparency, absorptivity and emissivity) on radiation frequency, as a result of interaction between matter and radiation. Multiple experiences are suggested to favour a progressive construction of knowledge on the physical aspects necessary to understand the greenhouse effect and global warming. Some results obtained with university students are briefly reported.

  4. Human impact on the planet: an earth system science perspective and ethical considerations

    Science.gov (United States)

    Williams, Richard S.

    2002-01-01

    The modern Earth Narrative, the scientific story of the 4.5 billion-year natural and human history of the Earth, has emerged from the solid foundation of two factual concepts: Deep (or Geologic) Time and Biological Evolution. spread acceptance of the Earth Narrative is critically important as we begin the third millennium, because it provides a clear understanding of the growing impact of human population growth and associated activities on the Earth System, especially the negative impact on Earth?s biosphere. It is important for humans to realize that we are but one of 4,500 species of mammals that exist on Earth and that we are but one species in the estimated 30 to 100 million species that form the complex biosphere. We also need to recognize that all species exist within the physical limits imposed by the geosphere. We are totally dependent on the biosphere for food, oxygen, and other necessities of life. mans are one of the latest results of biological evolution operating over a long period of Geologic Time. We find ourselves on Earth, after 4.5 billion years of Earth history by chance, not by design. Humans have become so successful at modifying their environment that many of the natural limitations on the expansion of populations of our fellow animals have been overcome by technological and cultural innovations. According to Peter Raven, ?Humans, at a current population of 6 billion [expected to nearly double by 2050], are consuming or wasting about 50 percent of the total net biological productivity on land and 50 percent of the available supply of freshwater. The overwhelming and expanding human presence leaves less and less room in the environment for other biota.? st century will be a pivotal time in the fate of Earth?s biosphere. Whereas human modification of the geosphere will slowly recover over time, human changes to the biosphere are a far more consequential matter? extinction of a species is forever! Will humans effectively use our new knowledge of

  5. The evolution of organic matter in space.

    Science.gov (United States)

    Ehrenfreund, Pascale; Spaans, Marco; Holm, Nils G

    2011-02-13

    Carbon, and molecules made from it, have already been observed in the early Universe. During cosmic time, many galaxies undergo intense periods of star formation, during which heavy elements like carbon, oxygen, nitrogen, silicon and iron are produced. Also, many complex molecules, from carbon monoxide to polycyclic aromatic hydrocarbons, are detected in these systems, like they are for our own Galaxy. Interstellar molecular clouds and circumstellar envelopes are factories of complex molecular synthesis. A surprisingly high number of molecules that are used in contemporary biochemistry on the Earth are found in the interstellar medium, planetary atmospheres and surfaces, comets, asteroids and meteorites and interplanetary dust particles. Large quantities of extra-terrestrial material were delivered via comets and asteroids to young planetary surfaces during the heavy bombardment phase. Monitoring the formation and evolution of organic matter in space is crucial in order to determine the prebiotic reservoirs available to the early Earth. It is equally important to reveal abiotic routes to prebiotic molecules in the Earth environments. Materials from both carbon sources (extra-terrestrial and endogenous) may have contributed to biochemical pathways on the Earth leading to life's origin. The research avenues discussed also guide us to extend our knowledge to other habitable worlds.

  6. Detecting gamma-ray anisotropies from decaying dark matter. Prospects for Fermi LAT

    International Nuclear Information System (INIS)

    Ibarra, Alejandro; Tran, David

    2009-09-01

    Decaying dark matter particles could be indirectly detected as an excess over a simple power law in the energy spectrum of the diffuse extragalactic gamma-ray background. Furthermore, since the Earth is not located at the center of the Galactic dark matter halo, the exotic contribution from dark matter decay to the diffuse gamma-ray flux is expected to be anisotropic, offering a complementary method for the indirect search for decaying dark matter particles. In this paper we discuss in detail the expected dipole-like anisotropies in the dark matter signal, taking also into account the radiation from inverse Compton scattering of electrons and positrons from dark matter decay. A different source for anisotropies in the gamma-ray flux are the dark matter density fluctuations on cosmic scales. We calculate the corresponding angular power spectrum of the gamma-ray flux and comment on observational prospects. Finally, we calculate the expected anisotropies for the decaying dark matter scenarios that can reproduce the electron/positron excesses reported by PAMELA and the Fermi LAT, and we estimate the prospects for detecting the predicted gamma-ray anisotropy in the near future. (orig.)

  7. The effective field theory of dark matter direct detection

    Energy Technology Data Exchange (ETDEWEB)

    Fitzpatrick, A. Liam; Haxton, Wick; Katz, Emanuel; Lubbers, Nicholas; Xu, Yiming

    2013-02-01

    We extend and explore the general non-relativistic effective theory of dark matter (DM) direct detection. We describe the basic non-relativistic building blocks of operators and discuss their symmetry properties, writing down all Galilean-invariant operators up to quadratic order in momentum transfer arising from exchange of particles of spin 1 or less. Any DM particle theory can be translated into the coefficients of an effective operator and any effective operator can be simply related to most general description of the nuclear response. We find several operators which lead to novel nuclear responses. These responses differ significantly from the standard minimal WIMP cases in their relative coupling strengths to various elements, changing how the results from different experiments should be compared against each other. Response functions are evaluated for common DM targets — F, Na, Ge, I, and Xe — using standard shell model techniques. We point out that each of the nuclear responses is familiar from past studies of semi-leptonic electroweak interactions, and thus potentially testable in weak interaction studies. We provide tables of the full set of required matrix elements at finite momentum transfer for a range of common elements, making a careful and fully model-independent analysis possible. Finally, we discuss embedding non-relativistic effective theory operators into UV models of dark matter.

  8. Extreme states of matter on earth and in the cosmos

    CERN Document Server

    Fortov, Vladimir E

    2011-01-01

    With its many beautiful colour pictures, this book gives fascinating insights into the unusual forms and behaviour of matter under extremely high pressures and temperatures. These extreme states are generated, among other things, by strong shock, detonation and electric explosion waves, dense laser beams,electron and ion beams, hypersonic entry of spacecraft into dense atmospheres of planets, and in many other situations characterized by extremely high pressures and temperatures. Written by one of the world's foremost experts on the topic, this book will inform and fascinate all scientists dealing with materials properties and physics, and also serve as an excellent introduction to plasma-, shock-wave and high-energy-density physics for students and newcomers seeking an overview.  

  9. Viscous dissipation of energy at the stage of accumulation of the Earth

    Science.gov (United States)

    Yurie Khachay, Professor; Olga Hachay, Professor; Antipin, Alexandr

    2017-04-01

    In the papers [1,2] it is published the differentiation model of the proto planet cloud during the accumulation of the Earth's group planets. In [2] it was shown that the energy released during the decay of short-lived radioactive elements in the small size more than 50 km, it is enough that the temperature inside of the protoplanet becomes larger than the temperature of iron melting. It provides a realization of the matter differentiation process and convection development inside the inner envelopes. With increasing of the Earth, the forming region of the outer core remains in a molten state, although the power and viscosity of the layer changed. In [3] it is shown that during the sequence of growth changes of accumulated protoplanets, the main contribution of heat is provided first by radioactive sources, and then heated from above by converting the kinetic energy during the growing impact inside the Earth, and finally heated from below. That provides three types of driving mechanisms of convection: internal heat sources; heated top; heated from bottom and chemical-thermal convection. At all stages of proto Earth's development the convective heat-mass transfer becomes a most significant factor in the dynamics of the planet. However, the heat release due to friction in the viscous liquid of the outer core up to now was not still considered, or it was considered only for the formed planetary envelopes with a constant radius. In this paper we present the first results of thermal evolution numerical modeling of 3D spherical segment for a protoplanet with increasing radius and accounting random falling of bodies and particles. To describe the planetary accumulation Safronov equation is used [4]. For the quantitative account of the released heat by viscous friction a system of hydro dynamic equations for a viscous liquid is used. The obtained results show that the heat input due to viscous friction heat release at the early stage of planetary accumulation was very

  10. Effect of 3-D heterogeneous-earth on rheology inference of postseismic model following the 2012 Indian Ocean earthquake

    Science.gov (United States)

    Pratama, C.; Ito, T.; Sasajima, R.; Tabei, T.; Kimata, F.; Gunawan, E.; Ohta, Y.; Yamashina, T.; Ismail, N.; Muksin, U.; Maulida, P.; Meilano, I.; Nurdin, I.; Sugiyanto, D.; Efendi, J.

    2017-12-01

    Postseismic deformation following the 2012 Indian Ocean earthquake has been modeled by several studies (Han et al. 2015, Hu et al. 2016, Masuti et al. 2016). Although each study used different method and dataset, the previous studies constructed a significant difference of earth structure. Han et al. (2015) ignored subducting slab beneath Sumatra while Masuti et al. (2016) neglect sphericity of the earth. Hu et al. (2016) incorporated elastic slab and spherical earth but used uniform rigidity in each layer of the model. As a result, Han et al. (2015) model estimated one order higher Maxwell viscosity than the Hu et al. (2016) and half order lower Kelvin viscosity than the Masuti et al. (2016) model predicted. In the present study, we conduct a quantitative analysis of each heterogeneous geometry and parameter effect on rheology inference. We develop heterogeneous three-dimensional spherical-earth finite element models. We investigate the effect of subducting slab, spherical earth, and three-dimensional earth rigidity on estimated lithosphere-asthenosphere rheology beneath the Indian Ocean. A wide range of viscosity structure from time constant rheology to time dependent rheology was chosen as previous studies have been modeled. In order to evaluate actual displacement, we compared the model to the Global Navigation Satellite System (GNSS) observation. We incorporate the GNSS data from previous studies and introduce new GNSS site as a part of the Indonesian Continuously Operating Reference Stations (InaCORS) located in Sumatra that has not been used in the last analysis. As a preliminary result, we obtained the effect of the spherical earth and elastic slab when we assumed burgers rheology. The model that incorporates the sphericity of the earth needs a one third order lower viscosity than the model that neglects earth curvature. The model that includes elastic slab needs half order lower viscosity than the model that excluding the elastic slab.

  11. Rare earth effect on microstructure, mechanical and tribological properties of CoCrW coatings

    International Nuclear Information System (INIS)

    Zhang Zhenyu; Lu Xinchun; Han Baolei; Luo Jianbin

    2007-01-01

    Eight different CoCrW coatings doped with rare earth oxide were deposited by supersonic plasma spraying (SPS). Environmental scanning electron microscopy, microhardness tester, X-ray diffractometer, and self-developed tribometer for high temperature were employed to investigate the properties of sprayed coatings. The results show that rare earth can refine the microstructure effectively, and make the element distribution uniform, which leads to the increase of average microhardness and the corresponding decrease of fluctuation range of sectioned surface of SPS coatings. Furthermore, the rare earth can reduce the friction coefficient between the SPS coating and glass during the sliding process at about 973 K largely, and the mechanism of anti-friction is also discussed

  12. Equidistant structure and effective nucleon mass in nuclear matter

    International Nuclear Information System (INIS)

    Tezuka, Hirokazu.

    1981-11-01

    The effective nucleon mass of the Equidistant Multi-Layer Structure (EMULS) is discussed self-consistently. In the density region where the Fermi gas state in nuclear matter is unstable against the density fluctuation, the EMULS gives lower binding energy. It is, however, shown that such a structure with an ordinary nucleon mass collapses due to too strong attraction. We point out that such a collapse can be avoided by taking account of an effective nucleon mass affected by the localization of nucleons. (author)

  13. Effects of Huge Earthquakes on Earth Rotation and the length of Day

    Directory of Open Access Journals (Sweden)

    Changyi Xu

    2013-01-01

    Full Text Available We calculated the co-seismic Earth rotation changes for several typical great earthquakes since 1960 based on Dahlen¡¦s analytical expression of Earth inertia moment change, the excitation functions of polar motion and, variation in the length of a day (ΔLOD. Then, we derived a mathematical relation between polar motion and earthquake parameters, to prove that the amplitude of polar motion is independent of longitude. Because the analytical expression of Dahlen¡¦s theory is useful to theoretically estimate rotation changes by earthquakes having different seismic parameters, we show results for polar motion and ΔLOD for various types of earthquakes in a comprehensive manner. The modeled results show that the seismic effect on the Earth¡¦s rotation decreases gradually with increased latitude if other parameters are unchanged. The Earth¡¦s rotational change is symmetrical for a 45° dip angle and the maximum changes appear at the equator and poles. Earthquakes at a medium dip angle and low latitudes produce large rotation changes. As an example, we calculate the polar motion and ΔLOD caused by the 2011 Tohoku-Oki Earthquake using two different fault models. Results show that a fine slip fault model is useful to compute co-seismic Earth rotation change. The obtained results indicate Dahlen¡¦s method gives good approximations for computation of co-seismic rotation changes, but there are some differences if one considers detailed fault slip distributions. Finally we analyze and discuss the co-seismic Earth rotation change signal using GRACE data, showing that such a signal is hard to be detected at present, but it might be detected under some conditions. Numerical results of this study will serve as a good indicator to check if satellite observations such as GRACE can detect a seismic rotation change when a great earthquake occur.

  14. Effects of anisotropic turbulent thermal diffusion on spherical magnetoconvection in the Earth's core

    Science.gov (United States)

    Ivers, D. J.; Phillips, C. G.

    2018-03-01

    We re-consider the plate-like model of turbulence in the Earth's core, proposed by Braginsky and Meytlis (1990), and show that it is plausible for core parameters not only in polar regions but extends to mid- and low-latitudes where rotation and gravity are not parallel, except in a very thin equatorial layer. In this model the turbulence is highly anisotropic with preferred directions imposed by the Earth's rotation and the magnetic field. Current geodynamo computations effectively model sub-grid scale turbulence by using isotropic viscous and thermal diffusion values significantly greater than the molecular values of the Earth's core. We consider a local turbulent dynamo model for the Earth's core in which the mean magnetic field, velocity and temperature satisfy the Boussinesq induction, momentum and heat equations with an isotropic turbulent Ekman number and Roberts number. The anisotropy is modelled only in the thermal diffusion tensor with the Earth's rotation and magnetic field as preferred directions. Nonlocal organising effects of gravity and rotation (but not aspect ratio in the Earth's core) such as an inverse cascade and nonlocal transport are assumed to occur at longer length scales, which computations may accurately capture with sufficient resolution. To investigate the implications of this anisotropy for the proposed turbulent dynamo model we investigate the linear instability of turbulent magnetoconvection on length scales longer than the background turbulence in a rotating sphere with electrically insulating exterior for no-slip and isothermal boundary conditions. The equations are linearised about an axisymmetric basic state with a conductive temperature, azimuthal magnetic field and differential rotation. The basic state temperature is a function of the anisotropy and the spherical radius. Elsasser numbers in the range 1-20 and turbulent Roberts numbers 0.01-1 are considered for both equatorial symmetries of the magnetic basic state. It is found

  15. PPPC 4 DMν: a Poor Particle Physicist Cookbook for Neutrinos from Dark Matter annihilations in the Sun

    Energy Technology Data Exchange (ETDEWEB)

    Baratella, Pietro [Scuola Normale Superiore and INFN, Piazza dei Cavalieri 7, Pisa, 56126 (Italy); Cirelli, Marco [Institut de Physique Théorique, CNRS URA 2306 and CEA-Saclay, Gif-sur-Yvette, 91191 (France); Hektor, Andi; Pata, Joosep; Piibeleht, Morten; Strumia, Alessandro, E-mail: pietro.baratella@sissa.it, E-mail: marco.cirelli@cea.fr, E-mail: andi.hektor@cern.ch, E-mail: joosep.pata@cern.ch, E-mail: morten.piibeleht@cern.ch, E-mail: alessandro.strumia@cern.ch [National Institute of Chemical Physics and Biophysics, Ravala 10, Tallinn (Estonia)

    2014-03-01

    We provide ingredients and recipes for computing neutrino signals of TeV-scale Dark Matter (DM) annihilations in the Sun. For each annihilation channel and DM mass we present the energy spectra of neutrinos at production, including: state-of-the-art energy losses of primary particles in solar matter, secondary neutrinos, electroweak radiation. We then present the spectra after propagation to the Earth, including (vacuum and matter) flavor oscillations and interactions in solar matter. We also provide a numerical computation of the capture rate of DM particles in the Sun. These results are available in numerical form.

  16. Secluded Dark Matter search in the Sun with the ANTARES neutrino telescope

    CERN Multimedia

    Adrián-Martínez, S

    2014-01-01

    Models where Dark Matter (DM) is secluded from the Standard Model via a mediator have increased their presence during the last decade to explain some experimental observations. This is a special scenario where DM, which would gravitationally accumulate in sources like the Sun, the Earth or the Galactic Centre, is annihilated into a non-standard Model mediator which subsequently decays into Standard Model particles, two co-linear muons for example. As the lifetime of the mediator could be large enough, its decay may occur in the vicinity of the Earth and the resulting SM particles could be detected. In this work we will describe the analysis for secluded dark matter coming from the Sun with ANTARES in three different cases: a) detection of di-muons that result of the mediator decay, or neutrino detection from: b) mediator that decays into di-muon and, in turn, into neutrinos, and c) mediator that directly decays into neutrinos. Sensitivities and results of the analysis for each case will be presented.

  17. The effects of refraction on transit transmission spectroscopy: application to Earth-like exoplanets

    Energy Technology Data Exchange (ETDEWEB)

    Misra, Amit; Meadows, Victoria [Astronomy Department, University of Washington, Box 351580, Seattle, WA 98195 (United States); Crisp, Dave, E-mail: amit0@astro.washington.edu [NAI Virtual Planetary Laboratory, Seattle, WA (United States)

    2014-09-01

    We quantify the effects of refraction in transit transmission spectroscopy on spectral absorption features and on temporal variations that could be used to obtain altitude-dependent spectra for planets orbiting stars of different stellar types. We validate our model against altitude-dependent transmission spectra of the Earth from ATMOS and against lunar eclipse spectra from Pallé et al. We perform detectability studies to show the potential effects of refraction on hypothetical observations of Earth analogs with the James Webb Space Telescope NIRSPEC. Due to refraction, there will be a maximum tangent pressure level that can be probed during transit for each given planet-star system. We show that because of refraction, for an Earth-analog planet orbiting in the habitable zone of a Sun-like star only the top 0.3 bars of the atmosphere can be probed, leading to a decrease in the signal-to-noise ratio (S/N) of absorption features by 60%, while for an Earth-analog planet orbiting in the habitable zone of an M5V star it is possible to probe almost the entire atmosphere with minimal decreases in S/N. We also show that refraction can result in temporal variations in the transit transmission spectrum which may provide a way to obtain altitude-dependent spectra of exoplanet atmospheres. Additionally, the variations prior to ingress and subsequent to egress provide a way to probe pressures greater than the maximum tangent pressure that can be probed during transit. Therefore, probing the maximum range of atmospheric altitudes, and in particular the near-surface environment of an Earth-analog exoplanet, will require looking at out-of-transit refracted light in addition to the in-transit spectrum.

  18. The effects of refraction on transit transmission spectroscopy: application to Earth-like exoplanets

    International Nuclear Information System (INIS)

    Misra, Amit; Meadows, Victoria; Crisp, Dave

    2014-01-01

    We quantify the effects of refraction in transit transmission spectroscopy on spectral absorption features and on temporal variations that could be used to obtain altitude-dependent spectra for planets orbiting stars of different stellar types. We validate our model against altitude-dependent transmission spectra of the Earth from ATMOS and against lunar eclipse spectra from Pallé et al. We perform detectability studies to show the potential effects of refraction on hypothetical observations of Earth analogs with the James Webb Space Telescope NIRSPEC. Due to refraction, there will be a maximum tangent pressure level that can be probed during transit for each given planet-star system. We show that because of refraction, for an Earth-analog planet orbiting in the habitable zone of a Sun-like star only the top 0.3 bars of the atmosphere can be probed, leading to a decrease in the signal-to-noise ratio (S/N) of absorption features by 60%, while for an Earth-analog planet orbiting in the habitable zone of an M5V star it is possible to probe almost the entire atmosphere with minimal decreases in S/N. We also show that refraction can result in temporal variations in the transit transmission spectrum which may provide a way to obtain altitude-dependent spectra of exoplanet atmospheres. Additionally, the variations prior to ingress and subsequent to egress provide a way to probe pressures greater than the maximum tangent pressure that can be probed during transit. Therefore, probing the maximum range of atmospheric altitudes, and in particular the near-surface environment of an Earth-analog exoplanet, will require looking at out-of-transit refracted light in addition to the in-transit spectrum.

  19. Search for dark matter annihilation in the earth using the ANTARES neutrino telescope

    NARCIS (Netherlands)

    Albert, A.; André, M.; Anghinolfi, M.; Anton, G.; Ardid, M.; Aubert, J.J.; Avgitas, T.; Baret, B.; Barrios-Marti, J.; Basa, S.; Bertin, V.; Biagi, S.; Bormuth, R.; Bourret, S.; Bouwhuis, M.C.; Bruijn, R.; Brunner, J.; Busto, J.; Capone, A.; Caramete, L.; Carr, J.; Celli, S.; Chiarusi, T.; Circella, M.; Coelho, J.A.; Coleiro, A.; Coniglione, R.; Costantini, H.; Coyle, P.; Creusot, A.; Deschamps, A.; De Bonis, G.; Distefano, C.; Di Palma, I.; Donzaud, C.; Dornic, D.; Drouhin, D.; Eberl, T.; El Bojaddaini, I.; Elsasser, D.; Enzenhofer, A.; Felis, I.; Fusco, L.A.; Galata, S.; Gay, P.; Geisselsoder, S.; Geyer, K.; Giordano, V.; Gleixner, A.; Glotin, H.; Grégoire, T.; Gracia-Ruiz, R.; Graf, K.; Hallmann, S.; van Haren, H.; Heijboer, A.J.; Hello, Y.; Hernandez-Rey, J.J.; Hofestadt, J.; Hugon, C.; Hossl, J.; Illuminati, G.; James, C.W.; de Jong, M.; Jongen, M.; Kadler, M.; Kalekin, O.; Katz, U.; Kiessling, D.; Kouchner, A.; Kreter, M.; Kreykenbohm, I.; Kulikovskiy, V.; Lachaud, C.; Lahmann, R.; Lefevre, D.; Leonora, E.; Lotze, M.; Loucatos, S.; Marcelin, M.; Margiotta, A.; Marinelli, A.; Martinez-Mora, J.A.; Mathieu, A.; Mele, R.; Melis, K.; Michael, T.; Migliozzi, P.; Moussa, A.; Mueller, C.; Nezri, E.; Pavalas, G.E.; Pellegrino, C.; Perrina, C.; Piattelli, P.; Popa, V.; Pradier, T.; Quinn, L.; Racca, C.; Riccobene, G.; Roensch, K.; Sanchez-Losa, A.; Saldana, M.; Salvadori, I.; Samtleben, D.F.E.; Sanguineti, M.; Sapienza, P.; Schnabel, J.; Schussler, F.; Seitz, T.; Sieger, C.; Spurio, M.; Stolarczyk, Th.; Taiuti, M.; Tayalati, Y.; Trovato, A.; Tselengidou, M.; Turpin, D.; Tönnis, C.; Vallage, B.; Vallee, C.; Van Elewyck, V.; Vivolo, D.; Vizzoca, A.; Wagner, S.; Wilms, J.; Zornoza, J.D.; Zuniga, J.

    2017-01-01

    A search for a neutrino signal from WIMP pair annihilations in the centre of the Earth has been performed with the data collected with the ANTARES neutrino telescope from 2007 to 2012. The event selection criteria have been developed and tuned to maximise the sensitivity of the experiment to such a

  20. Effect of four herbicides on microbial population, soil organic matter ...

    African Journals Online (AJOL)

    The effect of four herbicides (atrazine, primeextra, paraquat and glyphosate) on soil microbial population, soil organic matter and dehydrogenase activity was assessed over a period of six weeks. Soil samples from cassava farms were treated with herbicides at company recommended rates. Soil dehydrogenase activity was ...

  1. Foundations of high-energy-density physics physical processes of matter at extreme conditions

    CERN Document Server

    Larsen, Jon

    2017-01-01

    High-energy-density physics explores the dynamics of matter at extreme conditions. This encompasses temperatures and densities far greater than we experience on Earth. It applies to normal stars, exploding stars, active galaxies, and planetary interiors. High-energy-density matter is found on Earth in the explosion of nuclear weapons and in laboratories with high-powered lasers or pulsed-power machines. The physics explored in this book is the basis for large-scale simulation codes needed to interpret experimental results whether from astrophysical observations or laboratory-scale experiments. The key elements of high-energy-density physics covered are gas dynamics, ionization, thermal energy transport, and radiation transfer, intense electromagnetic waves, and their dynamical coupling. Implicit in this is a fundamental understanding of hydrodynamics, plasma physics, atomic physics, quantum mechanics, and electromagnetic theory. Beginning with a summary of the topics and exploring the major ones in depth, thi...

  2. Plasmas the first state of matter

    CERN Document Server

    Krishan, Vinod

    2014-01-01

    Most astronomers believe that the universe began about 15 billion years ago when an explosion led to its expansion and cooling. The present state of the universe compels us to believe that the universe was extremely hot and dense in its infancy. In the beginning there was intense radiation. The photons produced equal amounts of matter and antimatter and a plasma soup of particles and antiparticles was present. Plasma is the first state of matter from which all the other states originated. This book discusses the diversity of cosmic and terrestrial plasmas found in the early universe, galactic and intergalactic media, stellar atmospheres, interstellar spaces, the solar system and the Earth's ionosphere, and their observability with the most recent telescopes such as the Chandra X-ray telescope and gamma ray telescopes. It deals with different ways of creating plasmas such as thermal, pressure and radiative ionization for laboratory and cosmic plasmas.

  3. Crystal field parameters with Wannier functions: application to rare-earth aluminates

    Czech Academy of Sciences Publication Activity Database

    Novák, Pavel; Knížek, Karel; Kuneš, Jan

    2013-01-01

    Roč. 87, č. 20 (2013), "205139-1"-"205139-7" ISSN 1098-0121 R&D Projects: GA ČR(CZ) GAP204/11/0713 Institutional support: RVO:68378271 Keywords : crystal-field * rare earths * Wannier functions Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.664, year: 2013 http://link.aps.org/doi/10.1103/PhysRevB.87.205139

  4. Earth Sciences' Capacity Building In Developing Countries through International Programmes

    Science.gov (United States)

    Eder, W.

    2007-12-01

    Within the framework of "traditional" programmes, like the joint UNESCO-IUGS "International Geoscience Programme" (IGCP), the "International Continental Scientific Drilling Program" (ICDP), the "Integrated Ocean Drilling Program" (IODP) or the "International Lithosphere Programme" (ILP) numerous opportunities are provided to strengthen postgraduate geo-scientific education of representatives from developing countries. Recently established new initiatives, such as the "International Year of Planet Earth" (IYPE) or UNESCO's Global Network of Geoparks complement these in addition as important components to UNESCO's 'Education for All' programme, notably the youth, as well as to the United Nations Decade of Education for Sustainable Development (2005 - 2014). The "International Year of Planet Earth" is a joint initiative of the International Union of Geological Sciences (IUGS) and UNESCO. The central aims and ambitions of the Year, proclaimed for 2008 by the UN General Assembly, are to demonstrate the great potential of the Earth sciences in building a safer, healthier and wealthier society, and to encourage more widespread and effective application of this potential by targeting politicians and other decision-makers, educational systems, and the general public. Promotion of international collaboration, as well as capacity building and training of students of developing countries in all fields of Earth Sciences seem to be the most appropriate way to meet also the challenges of the IYPE. Another opportunity to improve the international recognition of Earth Scinces, also in developing countries, is the use of Geoparks as a promotional tool for education and popularization of Earth Sciences. Geoparks, notably those included in the European and/or Global Geoparks Networks, provide an international platform of cooperation and exchange between experts and practitioners in geological heritage matters, and are as such excellent instruments in highlighting Earth sciences. The

  5. Earth Science Outreach: A Move in the Right Direction

    Science.gov (United States)

    McLarty Halfkenny, B.; Schröder Adams, C.

    2009-05-01

    science and global issues such as climate science and stewardship of our natural resources. A new initiative for Science and Technology Week, 'Explore Geoheritage Day' introduced the public to the geological history of the National Capital Region. We have found collaborations with other agencies very effective. We work with PDAC's "Mining Matters", LTS, the Ottawa Gatineau Geoheritage Project, Ottawa Heritage, STAO, local school boards, naturalist groups, and other community organizations to promote Earth Science education. Our efforts over the last 5 years have brought tangible results in: a) a considerable increase in student enrolment at the university level in our department; b) increased teaching of the Grade 12 Earth and Space Sciences course at local high schools through teachers who were inspired by our workshops; c) a flourishing network of enthusiastic earth science educators sharing ideas with us to define each other's needs; and d) a growing interaction with the general public. Future initiatives need to consider lobbying for curriculum changes to give Earth Science a prominent place in the public education system. As well, only few university education departments currently allow Earth Science graduates into their programs, requiring them to first take additional courses in other "teachable" subjects. This must change. University graduates with an Earth Science degree and an interest in teaching must be permitted direct entry into these programs so that their skills will be passed on to the next generation of science students.

  6. Earth mortars and earth-lime renders

    Directory of Open Access Journals (Sweden)

    Maria Fernandes

    2008-01-01

    Full Text Available Earth surface coatings play a decorative architectural role, apart from their function as wall protection. In Portuguese vernacular architecture, earth mortars were usually applied on stone masonry, while earth renders and plasters were used on indoors surface coatings. Limestone exists only in certain areas of the country and consequently lime was not easily available everywhere, especially on granite and schist regions where stone masonry was a current building technique. In the central west coast of Portugal, the lime slaking procedure entailed slaking the quicklime mixed with earth (sandy soil, in a pit; the resulting mixture would then be combined in a mortar or plaster. This was also the procedure for manufactured adobes stabilized with lime. Adobe buildings with earth-lime renderings and plasters were also traditional in the same region, using lime putty and lime wash for final coat and decoration. Classic decoration on earth architecture from the 18th-19th century was in many countries a consequence of the François Cointeraux (1740-1830 manuals - Les Cahiers d'Architecture Rurale" (1793 - a French guide for earth architecture and building construction. This manual arrived to Portugal in the beginning of XIX century, but was never translated to Portuguese. References about decoration for earth houses were explained on this manual, as well as procedures about earth-lime renders and ornamentation of earth walls; in fact, these procedures are exactly the same as the ones used in adobe buildings in this Portuguese region. The specific purpose of the present paper is to show some cases of earth mortars, renders and plasters on stone buildings in Portugal and to explain the methods of producing earth-lime renders, and also to show some examples of rendering and coating with earth-lime in Portuguese adobe vernacular architecture.

  7. Evaluating litter decomposition and soil organic matter dynamics in earth system models: contrasting analysis of long-term litter decomposition and steady-state soil carbon

    Science.gov (United States)

    Bonan, G. B.; Wieder, W. R.

    2012-12-01

    Decomposition is a large term in the global carbon budget, but models of the earth system that simulate carbon cycle-climate feedbacks are largely untested with respect to litter decomposition. Here, we demonstrate a protocol to document model performance with respect to both long-term (10 year) litter decomposition and steady-state soil carbon stocks. First, we test the soil organic matter parameterization of the Community Land Model version 4 (CLM4), the terrestrial component of the Community Earth System Model, with data from the Long-term Intersite Decomposition Experiment Team (LIDET). The LIDET dataset is a 10-year study of litter decomposition at multiple sites across North America and Central America. We show results for 10-year litter decomposition simulations compared with LIDET for 9 litter types and 20 sites in tundra, grassland, and boreal, conifer, deciduous, and tropical forest biomes. We show additional simulations with DAYCENT, a version of the CENTURY model, to ask how well an established ecosystem model matches the observations. The results reveal large discrepancy between the laboratory microcosm studies used to parameterize the CLM4 litter decomposition and the LIDET field study. Simulated carbon loss is more rapid than the observations across all sites, despite using the LIDET-provided climatic decomposition index to constrain temperature and moisture effects on decomposition. Nitrogen immobilization is similarly biased high. Closer agreement with the observations requires much lower decomposition rates, obtained with the assumption that nitrogen severely limits decomposition. DAYCENT better replicates the observations, for both carbon mass remaining and nitrogen, without requirement for nitrogen limitation of decomposition. Second, we compare global observationally-based datasets of soil carbon with simulated steady-state soil carbon stocks for both models. The models simulations were forced with observationally-based estimates of annual

  8. Effectivity of the Earthworms Pheretima hupiensis, Eudrellus sp. and Lumbricus sp. on the Organic Matter Decomposition Process

    Directory of Open Access Journals (Sweden)

    Ea Kosman Anwar

    2009-05-01

    Full Text Available The earthworms are the one of soil fauna component in soil ecosystem have an important role in organic matter decomposition procces. The earthworm feed plant leaf and plant matter up to apart and dissolved. Earthworm metabolisms produce like faeces that mixed with decomposed organic matter mean vermicompost. The vermicompost fertility varies because of some kind of earthworm differ in “niche” and attitude. The experiment was to study the effectivity of earthworm on organic matter decomposition which has been conducted in Soil Biological and Healthy Laboratory and Green House of Soil Research Institute Bogor, during 2006 Budget Year. The three kind of earthworms i.e Pheretima hupiensis, Lumbricus sp. and Eudrellus sp. combined with three kind of organic matter sources i.e rice straw, trash and palm oil plant waste (compost heap. The result shows that the Lumbricus sp. are the most effective decomposer compared to Pheretima hupiensis and Eudrellus sp. and the organic matter decomposed by Lumbricus sp. as followed: market waste was decomposed of 100%, palm oil empty fruit bunch (compost heap 95.8 % and rice straw 84.9%, respectively. Earthworm effectively decreased Fe, Al, Mn, Cu dan Zn.

  9. Effect of stage of maturity on dry matter yield, morphological ...

    African Journals Online (AJOL)

    The experiment evaluated effect of stage of maturity on dry matter yield, morphological characteristics and nutritive value of burgundy bean (Macroptilium bracteatum) at the screen house of Department of Agronomy, Bayero University Kano, Nigeria. The treatments were 3 stages of growth repeated 3 times in a completely ...

  10. Investigating the Equatorial Gaps in Snowball Earth Sea Glaciers

    Science.gov (United States)

    Spaulding-Astudillo, F.; Ashkenazy, Y.; Tziperman, E.; Abbot, D. S.

    2017-12-01

    The way photosynthetic life survived the Neoproterozoic Snowball Earth events is still a matter of debate that has deep implications for planetary habitability. One option is that gaps in thick, semi-global ice coverage (sea glaciers) could be maintained at the equator by ocean-ice-atmosphere dynamics. We investigate this idea by modifying a global ocean-thick-marine-ice model developed for modeling Neoproterozoic Snowball Events to account for gaps in thick ice and interactions with atmospheric dynamics. Our hypothesis is that in the parameter regime that allows for sea glacier flow, ice flow will make gaps in the thick ice, and therefore an open ocean solution, less likely. This would suggest that oases in thick ice are a more viable survival mechanism for photosynthetic life during a Snowball Earth event.

  11. Effective neutron-proton interaction in rare earth odd-odd nuclei

    International Nuclear Information System (INIS)

    Boisson, Jean-Paul.

    1975-01-01

    The effective neutron-proton interaction V(np) in the rare earth odd-odd deformed nuclei is studied. The parameters of the effective interaction are determined from least square fits of calculated matrix elements compared to the ones extracted from experiment. These fits show the existence of a long range repulsive component as well the importance of the even term of the tensor part of V(np). Some informations are obtained concerning the influence of the choice of the sample of experimental data, of the average field and finally, of the radial shape of the effective interaction. Some predictions are made concerning as yet unconfirmed V(np) matrix elements [fr

  12. Nucleons, Nuclear Matter and Quark Matter: A unified NJL approach

    Energy Technology Data Exchange (ETDEWEB)

    S. Lawley; W. Bentz; A.W. Thomas

    2006-02-10

    We use an effective quark model to describe both hadronic matter and deconfined quark matter. By calculating the equations of state and the corresponding neutron star properties, we show that the internal properties of the nucleon have important implications for the properties of these systems.

  13. Nucleons, nuclear matter and quark matter: a unified NJL approach

    Energy Technology Data Exchange (ETDEWEB)

    Lawley, S [Special Research Centre for the Subatomic Structure of Matter, University of Adelaide, Adelaide SA 5005 (Australia); Bentz, W [Department of Physics, School of Science, Tokai University Hiratsuka-shi, Kanagawa 259-1292 (Japan); Thomas, A W [Jefferson Lab, 12000 Jefferson Avenue, Newport News, VA 23606 (United States)

    2006-05-01

    We use an effective quark model to describe both hadronic matter and deconfined quark matter. By calculating the equations of state and the corresponding neutron star properties, we show that the internal properties of the nucleon have important implications for the properties of these systems.

  14. Effects of rare earth elements La and Yb on the morphological and functional development of zebrafish embryos

    Institute of Scientific and Technical Information of China (English)

    Jun'an Cui; Zhiyong Zhang; Wei Bai; Ligang Zhang; Xiao He; Yuhui Ma; Yan Liu; Zhifang Chai

    2012-01-01

    In recent years,with the wide applications and mineral exploitation of rare earth elements,their potential environmental and health effects have caused increasing public concern.Effect of rare earth elements La and Yb on the morphological and functional development of zebrafish embryos were studied.The embryos were exposed to La3+ or Yb3+ at 0,0.01,0.1,0.3,0.5 and 1.0 mmol/L,respectively.Early life stage parameters such as egg and embryo mortality,gastrula development,tail detachment,eyes,somite formation,circulatory system,pigmentation,malformations,hatching rate,length of larvae and mortality were investigated.The results showed La3+ and Yb3+ delayed zebrafish embryo and larval development,decreased survival and hatching rates,and caused tail malformation in a concentration-dependent way.Moreover,heavy rare-earth ytterbium led to more severe acute toxicity of zebrafish embryo than light rare-earth lanthanum.

  15. Hyperons in nuclear matter from SU(3) chiral effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Petschauer, Stefan; Kaiser, Norbert [Technische Universitaet Muenchen (Germany); Haidenbauer, Johann [Forschungszentrum Juelich (Germany); Meissner, Ulf G. [Forschungszentrum Juelich (Germany); Universitaet Bonn (Germany); Weise, Wolfram [Technische Universitaet Muenchen (Germany); ECT, Trento (Italy)

    2016-07-01

    Brueckner theory is used to investigate the properties of hyperons in nuclear matter. The hyperon-nucleon interaction is taken from chiral effective field theory at next-to-leading order with SU(3) symmetric low-energy constants. Furthermore, the underlying nucleon-nucleon interaction is also derived within chiral effective field theory. We present the single-particle potentials of Λ and Σ hyperons in symmetric and asymmetric nuclear matter computed with the continuous choice for intermediate spectra. The results are in good agreement with the empirical information. In particular, our calculation gives a repulsive Σ-nuclear potential and a weak Λ-nuclear spin-orbit force. The splittings among the Σ{sup +}, Σ{sup 0} and Σ{sup -} potentials have a non-linear dependence on the isospin asymmetry which goes beyond the usual parametrization in terms of an isovector Lane potential.

  16. The Search for Primordial Molecular Cloud Matter

    DEFF Research Database (Denmark)

    van Kooten, Elishevah M M E

    evolution. Some of the least altered, most primitive meteorites can give us clues to the original make-up of the interstellar molecular cloud from which the Sun and its surrounding planets formed, thus, permitting us to trace Solar System formation from its most early conditions. Using state......Our Solar System today presents a somewhat static picture compared to the turbulent start of its existence. Meteorites are the left-over building blocks of planet formation and allow us to probe the chemical and physical processes that occurred during the first few million years of Solar System...... prebiotic species such as amino acids, determining the formation pathways of this organic matter is of utmost importance to understanding the habitability of Earth as well as exoplanetary systems. Hence, further detailed analyses of organic matter in some of the meteorites with primordial signatures have...

  17. A search for weakly interacting dark matter with the LUX experiment

    International Nuclear Information System (INIS)

    INIS-FR--11-0141/Pt.1-25

    2010-01-01

    Cosmological and astrophysical measurements indicate that our galaxy is filled with a new type of matter previously unknown to physics. This 'dark matter' apparently has no electromagnetic or strong interactions, but an interaction of the strength of the weak nuclear force is strongly suggested by the data. The LUX collaboration is attempting to detect the faint signature of weakly interacting dark matter as it passes through the earth. The experiment searches for recoiling atomic nuclei in a target consisting of 350 kg of liquefied xenon. LUX is the largest experiment of its type ever attempted, and it is expected to improve upon current experimental sensitivities by two orders of magnitude. The experiment is being assembled at the Sanford Underground Science and Engineering Laboratory (SUSEL) in Lead, South Dakota, USA, and first data is expected in 2011. We report on the status of LUX and the prospects for future large-scale dark matter searches with liquid xenon. (author)

  18. Dark matter effective field theory scattering in direct detection experiments

    Energy Technology Data Exchange (ETDEWEB)

    Schneck, K.; Cabrera, B.; Cerdeño, D. G.; Mandic, V.; Rogers, H. E.; Agnese, R.; Anderson, A. J.; Asai, M.; Balakishiyeva, D.; Barker, D.; Basu Thakur, R.; Bauer, D. A.; Billard, J.; Borgland, A.; Brandt, D.; Brink, P. L.; Bunker, R.; Caldwell, D. O.; Calkins, R.; Chagani, H.; Chen, Y.; Cooley, J.; Cornell, B.; Crewdson, C. H.; Cushman, P.; Daal, M.; Di Stefano, P. C. F.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Godfrey, G. L.; Golwala, S. R.; Hall, J.; Harris, H. R.; Hofer, T.; Holmgren, D.; Hsu, L.; Huber, M. E.; Jardin, D. M.; Jastram, A.; Kamaev, O.; Kara, B.; Kelsey, M. H.; Kennedy, A.; Leder, A.; Loer, B.; Lopez Asamar, E.; Lukens, P.; Mahapatra, R.; McCarthy, K. A.; Mirabolfathi, N.; Moffatt, R. A.; Morales Mendoza, J. D.; Oser, S. M.; Page, K.; Page, W. A.; Partridge, R.; Pepin, M.; Phipps, A.; Prasad, K.; Pyle, M.; Qiu, H.; Rau, W.; Redl, P.; Reisetter, A.; Ricci, Y.; Roberts, A.; Saab, T.; Sadoulet, B.; Sander, J.; Schnee, R. W.; Scorza, S.; Serfass, B.; Shank, B.; Speller, D.; Toback, D.; Upadhyayula, S.; Villano, A. N.; Welliver, B.; Wilson, J. S.; Wright, D. H.; Yang, X.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, J.

    2015-05-18

    We examine the consequences of the effective field theory (EFT) of dark matter–nucleon scattering for current and proposed direct detection experiments. Exclusion limits on EFT coupling constants computed using the optimum interval method are presented for SuperCDMS Soudan, CDMS II, and LUX, and the necessity of combining results from multiple experiments in order to determine dark matter parameters is discussed. We demonstrate that spectral differences between the standard dark matter model and a general EFT interaction can produce a bias when calculating exclusion limits and when developing signal models for likelihood and machine learning techniques. We also discuss the implications of the EFT for the next-generation (G2) direct detection experiments and point out regions of complementarity in the EFT parameter space.

  19. Interaction of ionizing radiation with matter

    International Nuclear Information System (INIS)

    Calisto, Washington

    1994-01-01

    Definition of ionizing radiation,interaction of electrons with matter,physical model of collision,elastic and inelastic collisions,range of electron in matter,interaction of photon with matter.Photoelectric effect , Compton effect,pair production,consideration of interaction of various radiations with soft tissue

  20. Atomic scale study of vacancies in Earth's inner core: effect of pressure and chemistry

    Science.gov (United States)

    Ritterbex, S.; Tsuchiya, T.

    2017-12-01

    Seismic observations of the Earth's inner core [1] remain ambiguously related to mineral physics studies of the inner core stable crystalline iron phase [2,3,4,5]. This makes it difficult to clarify the role of plastic deformation as one of the primary candidates responsible for the observed seismic anisotropy of Earth's inner core. Nonetheless, atomic self-diffusion mechanisms provide a direct link between plastic deformation and the mechanical properties of Earth's inner core stable iron phase(s). Using first-principles density functional based calculation techniques, we have studied the conjugate effect of pressure and chemistry on vacancy diffusion in HCP-, BCC- and FCC-iron by taking into account potential light alloying elements as hydrogen, silicon and sulfur. Our results show that inner core pressure highly inhibits the rate of intrinsic self-diffusion by suppressing defect concentration rather than by effecting the mobility of the defects. Moreover, we found light elements to be able to affect metallic bonding which allows for extrinsic diffusion mechanisms in iron under inner core conditions. The latter clearly enables to enhance defect concentration and hence to enhance the rate of plastic deformation. This suggests that inner core chemistry affects the rheological properties (e.g.viscosity) of iron alloys which finally should match with seismic observations. references: [1] Deuss, A., 2014. Heterogeneity and Anisotropy of Earth's inner core. An. Rev. Earth Planet. Sci. 42, 103-126. [2] Anzellini, S., Dewaele, A., Mezouar, M., Loubeyre, P., Morard, G., 2013. Melting of iron at Earth's inner core boundary based on fast X-ray diffraction. Science 340, 464-466. [3] Godwal, B.K., Gonzales-Cataldo, F., Verma, A.K., Stixrude, L., Jeanloz, R., 2015. Stability of iron crystal structures at 0.3-1.5 TPa. [4] Vocadlo, L., 2007. Ab initio calculations of the elasticity of iron and iron alloys at inner core conditions: evidence for a partially molten inner core

  1. Expected first-order effects of a notional equatorial ring on Earth's night sky: a geometric consideration

    Science.gov (United States)

    Hancock, L. O.

    2013-12-01

    : a schema of ring effects on the southern sky: (i) extinction of extra-terrestrial light between celestial equator and horizon; (ii) brightening of extra-terrestrial light via light-through-dust effects near the southern horizon; and (iii) reflection of sunlight from celestial equator to horizon. These effects would be modulated by season (due to ring self-shadowing) and hour of the night (because of Earth's shadow). We suggest that the expected effects are not "missing" at all - similar effects are well known to observers but are taken to be fully accounted for by skyglow, airglow and light pollution, qualitatively similar phenomena that certainly exist. We conclude that ground-based observers' non-identification of an equatorial ring is not a counter-indicator of a ring's existence. As far as this consideration goes, the question of an Earth ring system is open.

  2. Nuclear matter from chiral effective field theory

    International Nuclear Information System (INIS)

    Drischler, Christian

    2017-01-01

    Nuclear matter is an ideal theoretical system that provides key insights into the physics of different length scales. While recent ab initio calculations of medium-mass to heavy nuclei have demonstrated that realistic saturation properties in infinite matter are crucial for reproducing experimental binding energies and charge radii, the nuclear-matter equation of state allows tight constraints on key quantities of neutron stars. In the present thesis we take advantage of both aspects. Chiral effective field theory (EFT) with pion and nucleon degrees of freedom has become the modern low-energy approach to nuclear forces based on the symmetries of quantum chromodynamics, the fundamental theory of strong interactions. The systematic chiral expansion enables improvable calculations associated with theoretical uncertainty estimates. In recent years, chiral many-body forces were derived up to high orders, allowing consistent calculations including all many-body contributions at next-to-next-to-next-to-leading order (N 3 LO). Many further advances have driven the construction of novel chiral potentials with different regularization schemes. Here, we develop advanced methods for microscopic calculations of the equation of state of homogeneous nuclear matter with arbitrary proton-to-neutron ratio at zero temperature. Specifically, we push the limits of many-body perturbation theory (MBPT) considerations to high orders in the chiral and in the many-body expansion. To address the challenging inclusion of three-body forces, we introduce a new partial-wave method for normal ordering that generalizes the treatment of these contributions. We show improved predictions for the neutron-matter equation of state with consistent N 3 LO nucleon-nucleon (NN) plus three-nucleon (3N) potentials using MBPT up to third order and self-consistent Green's function theory. The latter also provides nonperturbative benchmarks for the many-body convergence. In addition, we extend the normal

  3. Nuclear matter from chiral effective field theory

    Energy Technology Data Exchange (ETDEWEB)

    Drischler, Christian

    2017-11-15

    Nuclear matter is an ideal theoretical system that provides key insights into the physics of different length scales. While recent ab initio calculations of medium-mass to heavy nuclei have demonstrated that realistic saturation properties in infinite matter are crucial for reproducing experimental binding energies and charge radii, the nuclear-matter equation of state allows tight constraints on key quantities of neutron stars. In the present thesis we take advantage of both aspects. Chiral effective field theory (EFT) with pion and nucleon degrees of freedom has become the modern low-energy approach to nuclear forces based on the symmetries of quantum chromodynamics, the fundamental theory of strong interactions. The systematic chiral expansion enables improvable calculations associated with theoretical uncertainty estimates. In recent years, chiral many-body forces were derived up to high orders, allowing consistent calculations including all many-body contributions at next-to-next-to-next-to-leading order (N{sup 3}LO). Many further advances have driven the construction of novel chiral potentials with different regularization schemes. Here, we develop advanced methods for microscopic calculations of the equation of state of homogeneous nuclear matter with arbitrary proton-to-neutron ratio at zero temperature. Specifically, we push the limits of many-body perturbation theory (MBPT) considerations to high orders in the chiral and in the many-body expansion. To address the challenging inclusion of three-body forces, we introduce a new partial-wave method for normal ordering that generalizes the treatment of these contributions. We show improved predictions for the neutron-matter equation of state with consistent N{sup 3}LO nucleon-nucleon (NN) plus three-nucleon (3N) potentials using MBPT up to third order and self-consistent Green's function theory. The latter also provides nonperturbative benchmarks for the many-body convergence. In addition, we extend the

  4. Stability and anisotropy of (FexNi1-x)2O under high pressure and implications in Earth's and super-Earths' core.

    Science.gov (United States)

    Huang, Shengxuan; Wu, Xiang; Qin, Shan

    2018-01-10

    Oxygen is thought to be an important light element in Earth's core but the amount of oxygen in Earth's core remains elusive. In addition, iron-rich iron oxides are of great interest and significance in the field of geoscience and condensed matter physics. Here, static calculations based on density functional theory demonstrate that I4/mmm-Fe 2 O is dynamically and mechanically stable and becomes energetically favorable with respect to the assemblage of hcp-Fe and [Formula: see text]-FeO above 270 GPa, which indicates that I4/mmm-Fe 2 O can be a strong candidate phase for stable iron-rich iron oxides at high pressure, perhaps even at high temperature. The elasticity and anisotropy of I4/mmm-(Fe x Ni 1-x ) 2 O at high pressures are also determined. Based on these results, we have derived the upper limit of oxygen to be 4.3 wt% in Earth's lower outer core. On the other hand, I4/mmm-(Fe x Ni 1-x ) 2 O with high AV S is likely to exist in a super-Earth's or an ocean planet's solid core causing the locally seismic heterogeneity. Our results not only give some clues to explore and synthesize novel iron-rich iron oxides but also shed light on the fundamental information of oxygen in the planetary core.

  5. Effective description of dark matter as a viscous fluid

    CERN Document Server

    Floerchinger, S.; Tetradis, N.; Wiedemann, U.A.

    2016-10-28

    Treating dark matter at large scales as an effectively viscous fluid provides an improved framework for the calculation of the density and velocity power spectra compared to the standard assumption of an ideal pressureless fluid. We discuss how this framework can be made concrete through an appropriate coarse-graining procedure. We also review results that demonstrate that it improves the convergence of cosmological perturbation theory.

  6. Effective description of dark matter as a viscous fluid

    International Nuclear Information System (INIS)

    Floerchinger, Stefan; Garny, Mathias; Tetradis, Nikolaos; Wiedemann, Urs Achim

    2016-01-01

    Treating dark matter at large scales as an effectively viscous fluid provides an improved framework for the calculation of the density and velocity power spectra compared to the standard assumption of an ideal pressureless fluid. We discuss how this framework can be made concrete through an appropriate coarse-graining procedure. We also review results that demonstrate that it improves the convergence of cosmological perturbation theory

  7. The fate or organic matter during planetary accretion - Preliminary studies of the organic chemistry of experimentally shocked Murchison meteorite

    Science.gov (United States)

    Tingle, Tracy N.; Tyburczy, James A.; Ahrens, Thomas J.; Becker, Christopher H.

    1992-01-01

    The fate of organic matter in carbonaceous meteorites during hypervelocity (1-2 km/sec) impacts is investigated using results of experiments in which three samples of the Murchison (CM2) carbonaceous chondrite were shocked to 19, 20, and 36 GPa and analyzed by highly sensitive thermal-desorption photoionization mass spectrometry (SALI). The thermal-desorptive SALI mass spectra of unshocked CM2 material revealed presence of indigenous aliphatic, aromatic, sulfur, and organosulfur compounds, and samples shocked to about 20 GPa showed little or no loss of organic matter. On the other hand, samples shocked to 36 GPa exhibited about 70 percent loss of organic material and a lower alkene/alkane ratio than did the starting material. The results suggest that it is unlikely that the indigenous organic matter in carbonaceous chondritelike planetesimals could have survived the impact on the earth in the later stages of earth's accretion.

  8. Hidden charged dark matter

    International Nuclear Information System (INIS)

    Feng, Jonathan L.; Kaplinghat, Manoj; Tu, Huitzu; Yu, Hai-Bo

    2009-01-01

    Can dark matter be stabilized by charge conservation, just as the electron is in the standard model? We examine the possibility that dark matter is hidden, that is, neutral under all standard model gauge interactions, but charged under an exact (\\rm U)(1) gauge symmetry of the hidden sector. Such candidates are predicted in WIMPless models, supersymmetric models in which hidden dark matter has the desired thermal relic density for a wide range of masses. Hidden charged dark matter has many novel properties not shared by neutral dark matter: (1) bound state formation and Sommerfeld-enhanced annihilation after chemical freeze out may reduce its relic density, (2) similar effects greatly enhance dark matter annihilation in protohalos at redshifts of z ∼ 30, (3) Compton scattering off hidden photons delays kinetic decoupling, suppressing small scale structure, and (4) Rutherford scattering makes such dark matter self-interacting and collisional, potentially impacting properties of the Bullet Cluster and the observed morphology of galactic halos. We analyze all of these effects in a WIMPless model in which the hidden sector is a simplified version of the minimal supersymmetric standard model and the dark matter is a hidden sector stau. We find that charged hidden dark matter is viable and consistent with the correct relic density for reasonable model parameters and dark matter masses in the range 1 GeV ∼ X ∼< 10 TeV. At the same time, in the preferred range of parameters, this model predicts cores in the dark matter halos of small galaxies and other halo properties that may be within the reach of future observations. These models therefore provide a viable and well-motivated framework for collisional dark matter with Sommerfeld enhancement, with novel implications for astrophysics and dark matter searches

  9. Proceedings of RIKEN BNL Research Center Workshop: P- and CP-odd Effects in Hot and Dense Matter

    Energy Technology Data Exchange (ETDEWEB)

    Deshpande, A.; Fukushima, K.; Kharzeev, D.; Warringa, H.; Voloshin, S.

    2010-04-26

    This volume contains the proceedings of the RBRC/CATHIE workshop on 'P- and CP-odd Effects in Hot and Dense Matter' held at the RIKEN-BNL Research Center on April 26-30, 2010. The workshop was triggered by the experimental observation of charge correlations in heavy ion collisions at RHIC, which were predicted to occur due to local parity violation (P- and CP-odd fluctuations) in hot and dense QCD matter. This experimental result excited a significant interest in the broad physics community, inspired a few alternative interpretations, and emphasized the need for a deeper understanding of the role of topology in QCD vacuum and in hot and dense quark-gluon matter. Topological effects in QCD are also closely related to a number of intriguing problems in condensed matter physics, cosmology and astrophysics. We therefore felt that a broad cross-disciplinary discussion of topological P- and CP-odd effects in various kinds of matter was urgently needed. Such a discussion became the subject of the workshop. Specific topics discussed at the workshop include the following: (1) The current experimental results on charge asymmetries at RHIC and the physical interpretations of the data; (2) Quantitative characterization of topological effects in QCD matter including both analytical (perturbative and non-perturbative using gauge/gravity duality) and numerical (lattice-QCD) calculations; (3) Topological effects in cosmology of the Early Universe (including baryogenesis and dark energy); (4) Topological effects in condensed matter physics (including graphene and superfiuids); and (5) Directions for the future experimental studies of P- and CP-odd effects at RHIC and elsewhere. We feel that the talks and intense discussions during the workshop were extremely useful, and resulted in new ideas in both theory and experiment. We hope that the workshop has contributed to the progress in understanding the role of topology in QCD and related fields. We thank all the speakers and

  10. Proceedings of RIKEN BNL Research Center Workshop: P- and CP-odd Effects in Hot and Dense Matter

    International Nuclear Information System (INIS)

    Deshpande, A.; Fukushima, K.; Kharzeev, D.; Warringa, H.; Voloshin, S.

    2010-01-01

    This volume contains the proceedings of the RBRC/CATHIE workshop on 'P- and CP-odd Effects in Hot and Dense Matter' held at the RIKEN-BNL Research Center on April 26-30, 2010. The workshop was triggered by the experimental observation of charge correlations in heavy ion collisions at RHIC, which were predicted to occur due to local parity violation (P- and CP-odd fluctuations) in hot and dense QCD matter. This experimental result excited a significant interest in the broad physics community, inspired a few alternative interpretations, and emphasized the need for a deeper understanding of the role of topology in QCD vacuum and in hot and dense quark-gluon matter. Topological effects in QCD are also closely related to a number of intriguing problems in condensed matter physics, cosmology and astrophysics. We therefore felt that a broad cross-disciplinary discussion of topological P- and CP-odd effects in various kinds of matter was urgently needed. Such a discussion became the subject of the workshop. Specific topics discussed at the workshop include the following: (1) The current experimental results on charge asymmetries at RHIC and the physical interpretations of the data; (2) Quantitative characterization of topological effects in QCD matter including both analytical (perturbative and non-perturbative using gauge/gravity duality) and numerical (lattice-QCD) calculations; (3) Topological effects in cosmology of the Early Universe (including baryogenesis and dark energy); (4) Topological effects in condensed matter physics (including graphene and superfiuids); and (5) Directions for the future experimental studies of P- and CP-odd effects at RHIC and elsewhere. We feel that the talks and intense discussions during the workshop were extremely useful, and resulted in new ideas in both theory and experiment. We hope that the workshop has contributed to the progress in understanding the role of topology in QCD and related fields. We thank all the speakers and

  11. PPPC 4 DMν: a Poor Particle Physicist Cookbook for Neutrinos from Dark Matter annihilations in the Sun

    International Nuclear Information System (INIS)

    Baratella, Pietro; Cirelli, Marco; Hektor, Andi; Pata, Joosep; Piibeleht, Morten; Strumia, Alessandro

    2014-01-01

    We provide ingredients and recipes for computing neutrino signals of TeV-scale Dark Matter (DM) annihilations in the Sun. For each annihilation channel and DM mass we present the energy spectra of neutrinos at production, including: state-of-the-art energy losses of primary particles in solar matter, secondary neutrinos, electroweak radiation. We then present the spectra after propagation to the Earth, including (vacuum and matter) flavor oscillations and interactions in solar matter. We also provide a numerical computation of the capture rate of DM particles in the Sun. These results are available in numerical form http://www.marcocirelli.net/PPPC4DMID.html

  12. PPPC 4 DMν: a Poor Particle Physicist Cookbook for Neutrinos from Dark Matter annihilations in the Sun

    Energy Technology Data Exchange (ETDEWEB)

    Baratella, Pietro [Scuola Normale Superiore and INFN, Piazza dei Cavalieri 7, Pisa, 56126 (Italy); Cirelli, Marco [Institut de Physique Théorique, CNRS URA 2306 & CEA-Saclay, Gif-sur-Yvette, 91191 (France); Hektor, Andi [National Institute of Chemical Physics and Biophysics, Ravala 10, Tallinn (Estonia); Helsinki Institute of Physics, P.O. Box 64, Helsinki, FI-00014 (Finland); Pata, Joosep; Piibeleht, Morten [National Institute of Chemical Physics and Biophysics, Ravala 10, Tallinn (Estonia); Strumia, Alessandro [National Institute of Chemical Physics and Biophysics, Ravala 10, Tallinn (Estonia); Dipartimento di Fisica dell’Università di Pisa and INFN, Largo Buonarroti 2, Pisa (Italy)

    2014-03-27

    We provide ingredients and recipes for computing neutrino signals of TeV-scale Dark Matter (DM) annihilations in the Sun. For each annihilation channel and DM mass we present the energy spectra of neutrinos at production, including: state-of-the-art energy losses of primary particles in solar matter, secondary neutrinos, electroweak radiation. We then present the spectra after propagation to the Earth, including (vacuum and matter) flavor oscillations and interactions in solar matter. We also provide a numerical computation of the capture rate of DM particles in the Sun. These results are available in numerical form http://www.marcocirelli.net/PPPC4DMID.html.

  13. Gravitational waves in cold dark matter

    Science.gov (United States)

    Flauger, Raphael; Weinberg, Steven

    2018-06-01

    We study the effects of cold dark matter on the propagation of gravitational waves of astrophysical and primordial origin. We show that the dominant effect of cold dark matter on gravitational waves from astrophysical sources is a small frequency dependent modification of the propagation speed of gravitational waves. However, the magnitude of the effect is too small to be detected in the near future. We furthermore show that the spectrum of primordial gravitational waves in principle contains detailed information about the properties of dark matter. However, depending on the wavelength, the effects are either suppressed because the dark matter is highly nonrelativistic or because it contributes a small fraction of the energy density of the universe. As a consequence, the effects of cold dark matter on primordial gravitational waves in practice also appear too small to be detectable.

  14. arXiv Colored Dark Matter

    CERN Document Server

    De Luca, Valerio; Redi, Michele; Smirnov, Juri; Strumia, Alessandro

    2018-06-14

    We explore the possibility that Dark Matter is the lightest hadron made of two stable color octet Dirac fermions ${\\cal Q}$. The cosmological DM abundance is reproduced for $M_{\\cal Q}\\approx 12.5$ TeV, compatibly with direct searches (the Rayleigh cross section, suppressed by $1/M_{\\cal Q}^6$, is close to present bounds), indirect searches (enhanced by ${\\cal Q}{\\cal Q}+\\bar{\\cal Q}\\bar{\\cal Q}\\to {\\cal Q}\\bar{\\cal Q}+{\\cal Q}\\bar{\\cal Q}$ recombination), and with collider searches (where ${\\cal Q}$ manifests as tracks, pair produced via QCD). Hybrid hadrons, made of $\\cal Q$ and of SM quarks and gluons, have large QCD cross sections, and do not reach underground detectors. Their cosmological abundance is $10^5$ times smaller than DM, such that their unusual signals seem compatible with bounds. Those in the Earth and stars sank to their centers; the Earth crust and meteorites later accumulate a secondary abundance, although their present abundance depends on nuclear and geological properties that we cannot c...

  15. Colored Dark Matter arXiv

    CERN Document Server

    De Luca, Valerio; Redi, Michele; Smirnov, Juri; Strumia, Alessandro

    We explore the possibility that Dark Matter is the lightest hadron made of two stable color octet Dirac fermions ${\\cal Q}$. The cosmological DM abundance is reproduced for $M_{\\cal Q}\\approx 12.5$ TeV, compatibly with direct searches (the Rayleigh cross section, suppressed by $1/M_{\\cal Q}^6$, is close to present bounds), indirect searches (enhanced by ${\\cal Q}{\\cal Q}+\\bar{\\cal Q}\\bar{\\cal Q}\\to {\\cal Q}\\bar{\\cal Q}+{\\cal Q}\\bar{\\cal Q}$ recombination), and with collider searches (where ${\\cal Q}$ manifests as tracks, pair produced via QCD). Hybrid hadrons, made of $\\cal Q$ and of SM quarks and gluons, have large QCD cross sections, and do not reach underground detectors. Their cosmological abundance is $10^5$ times smaller than DM, such that their unusual signals seem compatible with bounds. Those in the Earth and stars sank to their centers; the Earth crust and meteorites later accumulate a secondary abundance, although their present abundance depends on nuclear and geological properties that we cannot c...

  16. Organic chemistry in a CO2 rich early Earth atmosphere

    Science.gov (United States)

    Fleury, Benjamin; Carrasco, Nathalie; Millan, Maëva; Vettier, Ludovic; Szopa, Cyril

    2017-12-01

    The emergence of life on the Earth has required a prior organic chemistry leading to the formation of prebiotic molecules. The origin and the evolution of the organic matter on the early Earth is not yet firmly understood. Several hypothesis, possibly complementary, are considered. They can be divided in two categories: endogenous and exogenous sources. In this work we investigate the contribution of a specific endogenous source: the organic chemistry occurring in the ionosphere of the early Earth where the significant VUV contribution of the young Sun involved an efficient formation of reactive species. We address the issue whether this chemistry can lead to the formation of complex organic compounds with CO2 as only source of carbon in an early atmosphere made of N2, CO2 and H2, by mimicking experimentally this type of chemistry using a low pressure plasma reactor. By analyzing the gaseous phase composition, we strictly identified the formation of H2O, NH3, N2O and C2N2. The formation of a solid organic phase is also observed, confirming the possibility to trigger organic chemistry in the upper atmosphere of the early Earth. The identification of Nitrogen-bearing chemical functions in the solid highlights the possibility for an efficient ionospheric chemistry to provide prebiotic material on the early Earth.

  17. The Effects of Admixed Dark Matter on Accretion Induced Collapse

    Science.gov (United States)

    Leung, Shing-Chi; Chu, Ming-Chung; Lin, Lap-Ming; Nomoto, Ken'ichi

    About 90% mass of matter in the universe is dark matter (DM) and most of its properties remain poorly constrained since it does not interact with electromagnetic and strong forces. To constrain the properties of DM, studying its effects on stellar objects is one of the methods. In [Leung et al., Phys. Rev. D 87, 123506 (2013); Leung et al., Astrophys. J. 812, 110 (2015)] we have shown that the dark matter admixture can significantly lower the Chandrasekhar mass of a white dwarf and also its corresponding explosion as a Type Ia supernova (SNe Ia). This type of objects may explain some observed sub-luminous SNe Ia. Depending on their stellar evolution path and interactions with companion stars, such objects can also undergo a direct collapse to form neutron stars (NSs) instead of explosion. Here we present results of one-dimensional hydrodynamics simulations of a NS with admixed DM. The DM is assumed to be asymmetric and in the form of an ideal degenerate Fermi gas. We study how the admixture of DM affects the collapse dynamics, its neutrino signals and the properties of the proto-NS. Possible observational signals are also discussed.

  18. Assessment of the effect of three-dimensional mantle density heterogeneity on earth rotation in tidal frequencies.

    Science.gov (United States)

    Liu, Lanbo; Chao, Benjamin F; Sun, Wenke; Kuang, Weijia

    2016-11-01

    In this paper we report the assessment of the effect of the three-dimensional (3D) density heterogeneity in the mantle on Earth Orientation Parameters (EOP) (i.e., the polar motion, or PM, and the length of day, or LOD) in the tidal frequencies. The 3D mantle density model is estimated based upon a global S-wave velocity tomography model (S16U6L8) and the mineralogical knowledge derived from laboratory experiment. The lateral density variation is referenced against the Preliminary Reference Earth Model (PREM). Using this approach the effects of the heterogeneous mantle density variation in all three tidal frequencies (zonal long periods, tesseral diurnal, and sectorial semidiurnal) are estimated in both PM and LOD. When compared with mass or density perturbations originated on the earth's surface such as the oceanic and barometric changes, the heterogeneous mantle only contributes less than 10% of the total variation in PM and LOD in tidal frequencies. Nevertheless, including the 3D variation of the density in the mantle into account explained a substantial portion of the discrepancy between the observed signals in PM and LOD extracted from the lump-sum values based on continuous space geodetic measurement campaigns (e.g., CONT94) and the computed contribution from ocean tides as predicted by tide models derived from satellite altimetry observations (e.g., TOPEX/Poseidon). In other word, the difference of the two, at all tidal frequencies (long-periods, diurnals, and semi-diurnals) contains contributions of the lateral density heterogeneity of the mantle. Study of the effect of mantle density heterogeneity effect on torque-free earth rotation may provide useful constraints to construct the Reference Earth Model (REM), which is the next major objective in global geophysics research beyond PREM.

  19. Dark matter and dark radiation

    International Nuclear Information System (INIS)

    Ackerman, Lotty; Buckley, Matthew R.; Carroll, Sean M.; Kamionkowski, Marc

    2009-01-01

    We explore the feasibility and astrophysical consequences of a new long-range U(1) gauge field ('dark electromagnetism') that couples only to dark matter, not to the standard model. The dark matter consists of an equal number of positive and negative charges under the new force, but annihilations are suppressed if the dark-matter mass is sufficiently high and the dark fine-structure constant α-circumflex is sufficiently small. The correct relic abundance can be obtained if the dark matter also couples to the conventional weak interactions, and we verify that this is consistent with particle-physics constraints. The primary limit on α-circumflex comes from the demand that the dark matter be effectively collisionless in galactic dynamics, which implies α-circumflex -3 for TeV-scale dark matter. These values are easily compatible with constraints from structure formation and primordial nucleosynthesis. We raise the prospect of interesting new plasma effects in dark-matter dynamics, which remain to be explored.

  20. The Sun and its Planets as detectors for invisible matter

    Science.gov (United States)

    Bertolucci, Sergio; Zioutas, Konstantin; Hofmann, Sebastian; Maroudas, Marios

    2017-09-01

    Gravitational lensing of invisible streaming matter towards the Sun with speeds around 10-4 to 10-3 c could be the explanation of the puzzling solar flares and the unexplained solar emission in the EUV. Assuming that this invisible massive matter has some form of interaction with normal matter and that preferred directions exist in its flow, then one would expect a more pronounced solar activity at certain planetary heliocentric longitudes. This is best demonstrated in the case of the Earth and the two inner planets, considering their relatively short revolution time (365, 225 and 88 days) in comparison to a solar cycle of about 11 years. We have analyzed the solar flares as well as the EUV emission in the periods 1976-2015 and 1999-2015, respectively. The results derived from each data set mutually exclude systematics as the cause of the observed planetary correlations. We observe statistically significant signals when one or more planets have heliocentric longitudes mainly between 230° and 300°. We also analyzed daily data of the global ionization degree of the dynamic Earth atmosphere taken in the period 1995-2012. Again here, we observe a correlation between the total atmospheric electron content (TEC) and the orbital position of the inner three planets. Remarkably, the strongest correlation appears with the phase of the Moon. The broad velocity spectrum of the assumed constituents makes it difficult at this stage to identify its source(s) in space. More refined analyses might in the future increase the precision in the determination of the stream(s) direction and possibly allow to infer some properties of its constituents. Presently, no firmly established model of massive streaming particles exists, although in the literature there are abundant examples of hypotheses. Among them, the anti-quark nuggets model for dark matter seems the better suited to explain our observations and deserves further study.

  1. Cold matter effects and quarkonium production at RHIC and LHC

    Energy Technology Data Exchange (ETDEWEB)

    Dos Santos, G. S.; Mariotto, C. B. [Instituto de Matematica, Estatistica e Fisica, Universidade Federal do Rio Grande, Caixa Postal 474, CEP 96203-900, Rio Grande, RS (Brazil); Goncalves, V. P. [Instituto de Fisica e Matematica, Universidade Federal de Pelotas, Caixa Postal 354, CEP 96010-090, Pelotas, RS (Brazil)

    2013-03-25

    In this work we investigate two cold matter effects in J/{Psi} and {Upsilon} production in nuclear collisions at RHIC and LHC, namely the shadowing effect and nuclear absorption. We characterize these effects by estimating the rapidity dependence of some nuclear ratios in pA and AA collisions at RHIC and LHC, R{sub pA} = d{sigma}{sub pA}(J/{Psi},{Upsilon})/Ad{sigma}{sub pp}(J/{Psi},{Upsilon}) and R{sub AA} = d{sigma}{sub AA}(J/{Psi},{Upsilon})/A{sup 2}d{sigma}{sub pp}(J/{Psi},{Upsilon}).

  2. Effect of Earth's rotation on the quantum mechanical phase of the neutron

    International Nuclear Information System (INIS)

    Werner, S.A.; Staudenmann, J.; Colella, R.

    1979-01-01

    Using a neutron interferometer of the type first developed by Bonse and Hart for x rays, we have observed the effect of Earth's rotation on the phase of the neutron wave function. This experiment is the quantum mechanical analog of the optical interferometry observations of Michelson, Gale, and Pearson

  3. Thermal Inertia of near-Earth Asteroids and Strength of the Yarkovsky Effect

    NARCIS (Netherlands)

    Delbo, Marco; Dell'Oro, A.; Harris, A. W.; Mottola, S.; Mueller, M.

    2006-01-01

    Thermal inertia is the physical parameter that controls the temperature distribution over the surface of an asteroid. It affects the strength of the Yarkovsky effect, which causes orbital drift of km-sized asteroids and is invoked to explain the delivery of near-Earth asteroids (NEAs) from the main

  4. Clouds and the earth's radiation balance

    Energy Technology Data Exchange (ETDEWEB)

    Schmetz, J; Raschke, E

    1986-01-01

    Cloud formation mechanisms and cloud effects must be known for all regions of the earth for two important purposes of weather and climate research: First, the circulation characteristics of the atmosphere can be defined and understood only if the energy transfer between the atmosphere and the earth's surface is known; secondly, the energy transfer calculations should be as realistic as possible. The article discusses the influence of clouds on the radiation balance of the earth/atmosphere radiation balance, and the effects on weather and climate.

  5. Effect of Earth gravitational field on the detection of gravitational waves

    International Nuclear Information System (INIS)

    Denisov, V.I.; Eliseev, V.A.

    1987-01-01

    Results of laboratory detection of high-frequency gravitational waves from the view point of gravitation theories formulated on the basis of pseudoeuclidean space-time are calculated. Peculiarities due to different effects of the Earth gravitational field on the rates of gravitational and electromagnetic wave propagation in these theories are analysed. Experiments on check of predictions of the given class of theories are suggested

  6. Effects of Aerobic Capacity on Thrombin-Induced Hydrocephalus and White Matter Injury.

    Science.gov (United States)

    Ni, Wei; Gao, Feng; Zheng, Mingzhe; Koch, Lauren G; Britton, Steven L; Keep, Richard F; Xi, Guohua; Hua, Ya

    2016-01-01

    We have previously shown that intracerebral hemorrhage-induced brain injury is less in rats bred for high aerobic capacity (high capacity runners; HCR) compared with those bred for low aerobic capacity (low capacity runners; LCRs). Thrombin, an essential component in the coagulation cascade, is produced after cerebral hemorrhage. Intraventricular injection of thrombin causes significant hydrocephalus and white matter damage. In the present study, we examined the effect of exercise capacity on thrombin-induced hydrocephalus and white matter damage. Mid-aged (13-month-old) female LCRs (n = 13) and HCRs (n = 12) rats were used in this study. Rats received an intraventricular injection of thrombin (3 U, 50 μl). All rats underwent magnetic resonance imaging (MRI) at 24 h and were then euthanized for brain histology and Western blot. The mortalities were 20 % in LCRs and 33 % in HCRs after thrombin injection (p > 0.05). No rats died after saline injection. Intraventricular thrombin injection resulted in hydrocephalus and periventricular white matter damage as determined on MRI. In LCR rats, thrombin induced significant ventricle enlargement (23.0 ± 2.3 vs12.8 ± 1.9 mm(3) in LCR saline group; p hydrocephalus in rats with low aerobic capacity. A differential effect of thrombin may contribute to differences in the effects of cerebral hemorrhage with aerobic capacity.

  7. The Effect of Displacement Mode of Rigid Retaining Walls on Shearing Bands by Active Earth Pressure

    Directory of Open Access Journals (Sweden)

    A. Sekkel

    2013-10-01

    Full Text Available This work treats the physical modeling of failure mechanisms by active earth pressure. This last is developed by retaining wall movement. A lot of research showed that wall displacement has a significant effect on active earth pressure. A good comprehension of active earth pressure phenomenon and its failure mechanisms help us to better conceive retaining walls. The conception of a small-scale model allowed the realization of active earth pressure tests, while displacing the mobile wall toward the outside of the massif. The studied material is that of Schneebeli; light two-dimensional material made of cylindrical plastic rollers, simulating granular non-cohesive soil. The evolution of shearing zones under continuous and discontinuous displacement modes of mobile walls by correlation pictures allows the investigation of the localization of deformations and failure mechanisms.

  8. Introducing Earth's Orbital Eccentricity

    Science.gov (United States)

    Oostra, Benjamin

    2015-01-01

    Most students know that planetary orbits, including Earth's, are elliptical; that is Kepler's first law, and it is found in many science textbooks. But quite a few are mistaken about the details, thinking that the orbit is very eccentric, or that this effect is somehow responsible for the seasons. In fact, the Earth's orbital eccentricity is…

  9. Energy conservation in the earth's crust and climate change.

    Science.gov (United States)

    Mu, Yao; Mu, Xinzhi

    2013-02-01

    Among various matters which make up the earth's crust, the thermal conductivity of coal, oil, and oil-gas, which are formed over a long period of geological time, is extremely low. This is significant to prevent transferring the internal heat of the earth to the thermal insulation of the surface, cooling the surface of the earth, stimulating biological evolution, and maintaining natural ecological balance as well. Fossil energy is thermal insulating layer in the earth's crust. Just like the function of the thermal isolation of subcutaneous fatty tissue under the dermis of human skin, it keeps the internal heat within the organism so it won't be transferred to the skin's surface and be lost maintaining body temperature at low temperatures. Coal, oil, oil-gas, and fat belong to the same hydrocarbons, and the functions of their thermal insulation are exactly the same. That is to say, coal, oil, and oil-gas are just like the earth's "subcutaneous fatty tissue" and objectively formed the insulation protection on earth's surface. This paper argues that the human large-scale extraction of fossil energy leads to damage of the earth's crust heat-resistant sealing, increasing terrestrial heat flow, or the heat flow as it is called, transferring the internal heat of the earth to Earth's surface excessively, and causing geotemperature and sea temperature to rise, thus giving rise to global warming. The reason for climate warming is not due to the expansion of greenhouse gases but to the wide exploitation of fossil energy, which destroyed the heat insulation of the earth's crust, making more heat from the interior of the earth be released to the atmosphere. Based on the energy conservation principle, the measurement of the increase of the average global temperature that was caused by the increase of terrestrial heat flow since the Industrial Revolution is consistent with practical data. This paper illustrates "pathogenesis" of climate change using medical knowledge. The

  10. Disrupted Thalamus White Matter Anatomy and Posterior Default Mode Network Effective Connectivity in Amnestic Mild Cognitive Impairment

    Directory of Open Access Journals (Sweden)

    Thomas Alderson

    2017-11-01

    Full Text Available Alzheimer’s disease (AD and its prodromal state amnestic mild cognitive impairment (aMCI are characterized by widespread abnormalities in inter-areal white matter fiber pathways and parallel disruption of default mode network (DMN resting state functional and effective connectivity. In healthy subjects, DMN and task positive network interaction are modulated by the thalamus suggesting that abnormal task-based DMN deactivation in aMCI may be a consequence of impaired thalamo-cortical white matter circuitry. Thus, this article uses a multimodal approach to assess white matter integrity between thalamus and DMN components and associated effective connectivity in healthy controls (HCs relative to aMCI patients. Twenty-six HC and 20 older adults with aMCI underwent structural, functional and diffusion MRI scanning using the high angular resolution diffusion-weighted acquisition protocol. The DMN of each subject was identified using independent component analysis (ICA and resting state effective connectivity was calculated between thalamus and DMN nodes. White matter integrity changes between thalamus and DMN were investigated with constrained spherical deconvolution (CSD tractography. Significant structural deficits in thalamic white matter projection fibers to posterior DMN components posterior cingulate cortex (PCC and lateral inferior parietal lobe (IPL were identified together with significantly reduced effective connectivity from left thalamus to left IPL. Crucially, impaired thalamo-cortical white matter circuitry correlated with memory performance. Disrupted thalamo-cortical structure was accompanied by significant reductions in IPL and PCC cortico-cortical effective connectivity. No structural deficits were found between DMN nodes. Abnormal posterior DMN activity may be driven by changes in thalamic white matter connectivity; a view supported by the close anatomical and functional association of thalamic nuclei effected by AD pathology and

  11. Organic matter and soil moisture content and double cropping with organic matter sourceplants

    OpenAIRE

    John Bako Baon; Aris Wibawa

    2005-01-01

    Double cropping of coffee with organic matter source plants is thought to increase organic matter content of soil. This study examined the effect of double cropping of coffee and organic matter source plants on soil organic matter content and yield of coffee plants. Arabica coffee trees in Andungsari Experimental Station (Bondowoso district), 1400 m asl. and climate type C; and Robusta coffee trees in Sumberasin Experimental Station (Malang district), 550 m asl. and climate type C, were used ...

  12. Biochar effect on the mineralization of soil organic matter

    Directory of Open Access Journals (Sweden)

    Sander Bruun

    2012-05-01

    Full Text Available The objective of this work was to verify whether the addition of biochar to the soil affects the degradation of litter and of soil organic matter (SOM. In order to investigate the effect of biochar on the mineralization of barley straw, soil was incubated with 14C-labelled barley straw with or without unlabelled biochar. To investigate the effect of straw on the mineralization of biochar, soil was incubated with 14C-labelled biochar with or without straw. In addition, to investigate the effect of biochar on old SOM, a soil labelled by applying labelled straw 40 years ago was incubated with different levels of biochar. All experiments had a control treatment, without any soil amendment. The effect of biochar on the straw mineralization was small and nonsignificant. Without biochar, 48±0.2% of the straw carbon was mineralized within the 451 days of the experiment. In comparison, 45±1.6% of C was mineralized after biochar addition of 1.5 g kg-1. In the SOM-labelled soil, the organic matter mineralized more slowly with the increasing doses of biochar. Biochar addition at 7.7 g kg-1 reduced SOM mineralization from 6.6 to 6.3%, during the experimental period. The addition of 15.5 g kg-1 of biochar reduced the mineralized SOM to 5.7%. There is no evidence of increased degradation of either litter or SOM due to biochar addition; consequently, there is no evidence of decreased stability of SOM.

  13. Assessment of the effect of three-dimensional mantle density heterogeneity on Earth rotation in tidal frequencies

    Directory of Open Access Journals (Sweden)

    Lanbo Liu

    2016-11-01

    Full Text Available In this paper, we report the assessment of the effect of the three-dimensional (3D density heterogeneity in the mantle on Earth orientation parameters (EOP (i.e., the polar motion, or PM, and the length of day, or LOD in the tidal frequencies. The 3D mantle density model is estimated based upon a global S-wave velocity tomography model (S16U6L8 and the mineralogical knowledge derived from laboratory experiment. The lateral density variation is referenced against the preliminary reference earth model (PREM. Using this approach the effects of the heterogeneous mantle density variation in all three tidal frequencies (zonal long periods, tesseral diurnal, and sectorial semidiurnal are estimated in both PM and LOD. When compared with mass or density perturbations originated on the Earth's surface such as the oceanic and barometric changes, the heterogeneous mantle contributes less than 10% of the total variation in PM and LOD in tidal frequencies. However, this is the gap that has not been explained to close the gap of the observation and modeling in PM and LOD. By computing the PM and LOD caused by 3D heterogeneity of the mantle during the period of continuous space geodetic measurement campaigns (e.g., CONT94 and the contribution from ocean tides as predicted by tide models derived from satellite altimetry observations (e.g., TOPEX/Poseidon in the same period, we got the lump-sum values of PM and LOD. The computed total effects and the observed PM and LOD are generally agree with each other. In another word, the difference of the observed PM and LOD and the model only considering ocean tides, at all tidal frequencies (long periods, diurnals, and semidiurnals contains the contributions of the lateral density heterogeneity of the mantle. Study of the effect of mantle density heterogeneity effect on torque-free Earth rotation may provide useful constraints to construct the reference earth model (REM, which is the next major objective in global

  14. Faraday effect in rare-earth ferrite garnets located in strong magnetic fields

    International Nuclear Information System (INIS)

    Valiev, U.V.; Zvezdin, A.K.; Krinchik, G.S.; Levitin, R.Z.; Mukimov, K.M.; Popov, A.I.

    1983-01-01

    The Faraday effect is investigated experimentally in single crystal specimens of rare earth iron garnets (REIG) R 3 Fe 5 O 12 (R=Y, Gd, Tb, Dy, Er, Tm, Yb, Eu, Sm and Ho) and also in mixed iron garnets Rsub(x)Ysub(3-x)Fesub(5)Osub(12) (R=Tb, Dy). The m.easurements are carried out in pulsed magnetic fields of intensity up to 200 kOe, in a temperature range from 4.2 to 300 K and at a wavelength of the light lambda=1.15 μm. The field dependence of the Faraday effect observed in the REIG cannot be explained if only the usually considered ''paramagnetic'' contribution to the Faraday effect is taken into account. A theory is developed which, besides the paramagnetic mechanism, takes into account a diamagnetic mechanism and also the mixing of the wave functions of the ground and excited multiplets. The contributions of each of these three mechanisms to the angle of rotation of the plane of polarization by the rare earth sublattice of the iron garnet are estimated theoretically. It is concluded that the mixing mechanism contributes significantly to the field and temperature dependences of the Faraday effect in REIG

  15. Search for domain wall dark matter with atomic clocks on board global positioning system satellites.

    Science.gov (United States)

    Roberts, Benjamin M; Blewitt, Geoffrey; Dailey, Conner; Murphy, Mac; Pospelov, Maxim; Rollings, Alex; Sherman, Jeff; Williams, Wyatt; Derevianko, Andrei

    2017-10-30

    Cosmological observations indicate that dark matter makes up 85% of all matter in the universe yet its microscopic composition remains a mystery. Dark matter could arise from ultralight quantum fields that form macroscopic objects. Here we use the global positioning system as a ~ 50,000 km aperture dark matter detector to search for such objects in the form of domain walls. Global positioning system navigation relies on precision timing signals furnished by atomic clocks. As the Earth moves through the galactic dark matter halo, interactions with domain walls could cause a sequence of atomic clock perturbations that propagate through the satellite constellation at galactic velocities ~ 300 km s -1 . Mining 16 years of archival data, we find no evidence for domain walls at our current sensitivity level. This improves the limits on certain quadratic scalar couplings of domain wall dark matter to standard model particles by several orders of magnitude.

  16. Neutron roton pairing effect on some even ven rare-earth proton-rich nuclei

    International Nuclear Information System (INIS)

    Mokhtari, D.

    2004-01-01

    The neutron roton pairing effect on some even ven rare-earth proton-rich nuclei is studied. It is taken into account, in the isovector case, within the framework of the generalized Bogoliubov-Valatin transformation, using Woods-Saxon single-particle energies. (author)

  17. Effect of crystalline electric fields and long-range magnetic order on superconductivity in rare earth alloys and compounds

    International Nuclear Information System (INIS)

    McCallum, R.W.

    1977-01-01

    The behavior of rare earth ions in a superconducting matrix has been studied in two distinct regimes. First, the effects of crystal field splitting of the 4f levels of a magnetic rare earth ion in the alloy system (LaPr)Sn 3 were investigated in the limit of low Pr 3+ concentration. In this system the rare earth impurity ions occupy random La sites in the crystal lattice. Second, the interaction of long-range magnetic order and superconductivity was explored in the ternary rare earth molybdenum chalcogenide systems. In these compounds the rare earth ions occupy periodic lattice sites in contrast to the random distribution of magnetic ions in dilute impurity alloy systems such as (LaPr)Sn 3

  18. Dark matter annihilation in the milky way galaxy: effects of baryonic compression.

    Science.gov (United States)

    Prada, F; Klypin, A; Flix, J; Martínez, M; Simonneau, E

    2004-12-10

    If the dark matter (DM), which is considered to constitute most of the mass of galaxies, is made of supersymmetric particles, the central region of our Galaxy should emit gamma rays produced by their annihilation. We use detailed models of the Milky Way to make accurate estimates of continuum gamma-ray fluxes. We argue that the most important effect, which was previously neglected, is the compression of the dark matter due to the infall of baryons to the galactic center: it boosts the expected signal by a factor 1000. To illustrate this effect, we computed the expected gamma fluxes in the minimal supergravity scenario. Our models predict that the signal could be detected at high confidence levels by imaging atmospheric C erenkov telescopes assuming that neutralinos make up most of the DM in the Universe.

  19. Development of novel rare earth doped fluoride and oxide scintillators for two-dimensional imaging

    Czech Academy of Sciences Publication Activity Database

    Yoshikawa, A.; Yanagida, T.; Yokota, Y.; Kamada, K.; Kawaguchi, N.; Fukuda, K.; Yamazaki, A.; Watanabe, K.; Uritani, A.; Iguchi, T.; Boulon, G.; Nikl, Martin

    2011-01-01

    Roč. 29, č. 12 (2011), s. 1178-1182 ISSN 1002-0721 Grant - others:AV ČR(CZ) M100100910 Institutional research plan: CEZ:AV0Z10100521 Keywords : scintillator * gamma-ray detection * neutron detection * fluoride * Ce * Eu * rare earth Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.901, year: 2011

  20. μSR-studies of magnetic properties of metallic rare earth compounds

    International Nuclear Information System (INIS)

    Asch, L.; Kalvius, G.M.; Chappert, J.; Yaouanc, A.; Hartmann, O.; Karlsson, E.; Wappling, R.

    1984-01-01

    Positive muons can probe the magnitude and the time dependence of the magnetic field at interstitial sites in condensed matter. Thus the relatively new techniques of muons spin rotation and muon spin relaxation have become unique tools for studying magnetism. After a brief introduction into the experimental method we then discuss measurements on the elemental rare earth metals and on intermetallic compounds, in particular on the cubic Laves phases REAl 2

  1. Magnus Effect on a Spinning Satellite in Low Earth Orbit

    Science.gov (United States)

    Ramjatan, Sahadeo; Fitz-Coy, Norman; Yew, Alvin Garwai

    2016-01-01

    A spinning body in a flow field generates an aerodynamic lift or Magnus effect that displaces the body in a direction normal to the freestream flow. Earth orbiting satellites with substantial body rotation in appreciable atmospheric densities may generate a Magnus force to perturb orbital dynamics. We investigate the feasibility of using this effect for spacecraft at a perigee of 80km using the Systems Tool Kit (STK). Results show that for a satellite of reasonable properties, the Magnus effect doubles the amount of time in orbit. Orbital decay was greatly mitigated for satellites spinning at 10000 and 15000RPM. This study demonstrates that the Magnus effect has the potential to sustain a spacecraft's orbit at a low perigee altitude and could also serve as an orbital maneuver capability.

  2. Effective Integration of the World-Wide Web in Earth Science Education.

    Science.gov (United States)

    Herbert, Bruce; Bednarz, Sarah; Boyd, Tom; Blake, Sally; Harder, Vicki; Sutter, Marilyn

    The earth sciences is an evolving set of disciplines encompassing more than 30 specialties; however, earth scientists continue to be trained within the traditional disciplinary structure. Earth science education should focus not only on student acquisition and retention of factual knowledge, but also on the development of higher-order skills…

  3. Signals of dark matter in a supersymmetric two dark matter model

    International Nuclear Information System (INIS)

    Fukuoka, Hiroki; Suematsu, Daijiro; Toma, Takashi

    2011-01-01

    Supersymmetric radiative neutrino mass models have often two dark matter candidates. One is the usual lightest neutralino with odd R parity and the other is a new neutral particle whose stability is guaranteed by a discrete symmetry that forbids tree-level neutrino Yukawa couplings. If their relic abundance is comparable, dark matter phenomenology can be largely different from the minimal supersymmetric standard model (MSSM). We study this in a supersymmetric radiative neutrino mass model with the conserved R parity and a Z 2 symmetry weakly broken by the anomaly effect. The second dark matter with odd parity of this new Z 2 is metastable and decays to the neutralino dark matter. Charged particles and photons associated to this decay can cause the deviation from the expected background of the cosmic rays. Direct search of the neutralino dark matter is also expected to show different features from the MSSM since the relic abundance is not composed of the neutralino dark matter only. We discuss the nature of dark matter in this model by analyzing these signals quantitatively

  4. Effects of cattle and poultry manures on organic matter content and ...

    African Journals Online (AJOL)

    The organic fertilizer showed significant effect on earthworms populations Hyperiodrilus africanus (Oligochaeta, Eudrilidae) in the soil, with 128 and 85% respectively about the poultry and cattle manures compared to the control (p < 0.01). Key words: Cattle manure, poultry manure, cassava, organic matter, cation exchange ...

  5. Effective interactions and mean field theory: from nuclear matter to nuclei

    International Nuclear Information System (INIS)

    Cochet, B.

    2005-07-01

    The Skyrme force is a zero-range force that allows the construction of the mean field inside the nucleus in a simple way. Skyrme forces are reasonably predictive but some features of the infinite nuclear matter or the mass of heavy nuclei are not well computed. The aim of this work is to propose an expanded parametrization of the Skyrme force in order to improve its predictive power. The first part is dedicated to the construction of the expansion of the parametrization. We recall how the effective forces are linked to the nucleon-nucleon interaction then we show the limits of the standard Skyrme forces and we propose a relatively natural improvements based on the integration of spin and isospin instabilities. The second part deals with the validation of the model, first by describing infinite nuclear matter then by studying β-balanced nuclear matter which has enabled us to reproduce some features of neutron stars like mass and radius. The computation of properties of nuclei like binding energy, mass, radii depends strongly on the adjustment procedure. (A.C.)

  6. The effect of acid rain stress on chlorophyll, peroxidase of the conservation of rare earth elements

    International Nuclear Information System (INIS)

    Chongling, Y.; Yetang, H.; Xianke, Y.; Shunzhen, F.; Shanql, W.

    1998-01-01

    Full text: Based on pot experiment, the effect of acid rain stress on chlorophyll, peroxidase of wheat, the relationship of them and the conservation of rare earth elements has been studied. The result showed: stress of acid rain resulted in decrease of chlorophyll content and a/b values, chlorophyll a/b value and chlorophyll content is positive correlation with pH value of acid rain: peroxidase activity was gradually rise with pH value decrease, which indirectly increased decomposition intensity of chlorophyll. Decreased content and a/b value of chlorophyll further speeded blade decay affected the transport and transformation of light energy and metabolism of carbohydrates. After being treated by rare earth elements content and pH value of chlorophyll and peroxidase activity could be relatively stable. Therefore, under lower acidity condition, rare earth elements can influence the effect of acid rain on chlorophyll and peroxidase activity of wheat

  7. Effect of organic matter on the uptake of phosphorus by rice plants under different moisture conditions

    International Nuclear Information System (INIS)

    Ghosh, Geetanjali

    1974-01-01

    In studies on the effect of three levels of moisture and two levels of organic matter in two alluvial soils, the uptake of P by rice plant both from soil and fertilizer sources was the highest and Eh the lowest under submerged conditions. No marked difference in total uptake of P was observed in upland and alternate submerged condition; organic matter application showed an appreciable effect under submerged condition. (author)

  8. Effects of mineral matter on products and sulfur distributions in hydropyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H.; Li, B.; Zhang, B. [Chinese Academy of Sciences, Taiyuan (China). Inst. of Coal Chemistry

    1999-05-01

    The effects of the mineral matter on the product yield and sulfur distribution in hydropyrolysis and pyrolysis of Chinese Hongmiao lignite were investigated using a fixed-bed reactor. The volatile sulfur-containing gases (H{sub 2}S, COS, CH{sub 3}SH) were also analyzed as a function of pyrolysis temperature. Coal samples were treated with HCl/HF or HCl/HF and CrCl{sub 2} solution to eliminate minerals and pyrite respectively. In hydropyrolysis, demineralized Hongmiao lignite showed lower yields of tar and water than the raw coal. Demineralization cannot only minimize the fixation effect of basic mineral matter on sulfur-containing gases, but also increase the sulfur distribution of the tar. Further, from the evolution profiles of sulfur-containing gases, it is possible to elucidate the contribution of minerals, pyrite and organic sulfur to the sulfur evolution. Pyrite may not be the only source of COS formation. 32 refs., 14 figs., 3 tabs.

  9. Research on Earth's rotation and the effect of atmospheric pressure on vertical deformation and sea level variability

    Science.gov (United States)

    Wahr, John

    1993-01-01

    The work done under NASA grant NAG5-485 included modelling the deformation of the earth caused by variations in atmospheric pressure. The amount of deformation near coasts is sensitive to the nature of the oceanic response to the pressure. The PSMSL (Permanent Service for Mean Sea Level) data suggest the response is inverted barometer at periods greater than a couple months. Green's functions were constructed to describe the perturbation of the geoid caused by atmospheric and oceanic loading and by the accompanying load-induced deformation. It was found that perturbation of up to 2 cm are possible. Ice mass balance data was used for continental glaciers to look at the glacial contributions to time-dependent changes in polar motion, the lod, the earth's gravitational field, the position of the earth's center-of-mass, and global sea level. It was found that there can be lateral, non-hydrostatic structure inside the fluid core caused by gravitational forcing from the mantle, from the inner core, or from topography at the core/mantle or inner core/outer core boundaries. The nutational and tidal response of a non-hydrostatic earth with a solid inner core was modeled. Monthly, global tide gauge data from PSMSL was used to look at the 18.6-year ocean tide, the 14-month pole tide, the oceanic response to pressure, the linear trend and inter-annual variability in the earth's gravity field, the global sea level rise, and the effects of post glacial rebound. The effects of mantle anelasticity on nutations, earth tides, and tidal variation in the lod was modeled. Results of this model can be used with Crustal Dynamics observations to look at the anelastic dissipation and dispersion at tidal periods. The effects of surface topography on various components of crustal deformation was also modeled, and numerical models were developed of post glacial rebound.

  10. Search for transient ultralight dark matter signatures with networks of precision measurement devices using a Bayesian statistics method

    Science.gov (United States)

    Roberts, B. M.; Blewitt, G.; Dailey, C.; Derevianko, A.

    2018-04-01

    We analyze the prospects of employing a distributed global network of precision measurement devices as a dark matter and exotic physics observatory. In particular, we consider the atomic clocks of the global positioning system (GPS), consisting of a constellation of 32 medium-Earth orbit satellites equipped with either Cs or Rb microwave clocks and a number of Earth-based receiver stations, some of which employ highly-stable H-maser atomic clocks. High-accuracy timing data is available for almost two decades. By analyzing the satellite and terrestrial atomic clock data, it is possible to search for transient signatures of exotic physics, such as "clumpy" dark matter and dark energy, effectively transforming the GPS constellation into a 50 000 km aperture sensor array. Here we characterize the noise of the GPS satellite atomic clocks, describe the search method based on Bayesian statistics, and test the method using simulated clock data. We present the projected discovery reach using our method, and demonstrate that it can surpass the existing constrains by several order of magnitude for certain models. Our method is not limited in scope to GPS or atomic clock networks, and can also be applied to other networks of precision measurement devices.

  11. Mimicking dark matter through a non-minimal gravitational coupling with matter

    International Nuclear Information System (INIS)

    Bertolami, O.; Páramos, J.

    2010-01-01

    In this study one resorts to the phenomenology of models endowed with a non-minimal coupling between matter and geometry, in order to develop a mechanism through which dynamics similar to that due to the presence of dark matter is generated. As a first attempt, one tries to account for the flattening of the galaxy rotation curves as an effect of the non-(covariant) conservation of the energy-momentum tensor of visible matter. Afterwards, one assumes instead that this non-minimal coupling modifies the scalar curvature in a way that can be interpreted as a dark matter component (albeit with negative pressure). It is concluded that it is possible to mimic known dark matter density profiles through an appropriate power-law coupling f 2 = (R/R 0 ) n , with a negative index n — a fact that reflects the dominance of dark matter at large distances. The properties of the model are extensively discussed, and possible cosmological implications are addressed

  12. Near-Earth Magnetic Field Effects of Large-Scale Magnetospheric Currents

    Science.gov (United States)

    Luehr, Hermann; Xiong, Chao; Olsen, Nils; Le, Guan

    2016-01-01

    Magnetospheric currents play an important role in the electrodynamics of near- Earth space. This has been the topic of many space science studies. Here we focus on the magnetic fields they cause close to Earth. Their contribution to the geomagnetic field is the second largest after the core field. Significant progress in interpreting the magnetic fields from the different sources has been achieved thanks to magnetic satellite missions like Ørsted, CHAMP and now Swarm. Of particular interest for this article is a proper representation of the magnetospheric ring current effect. Uncertainties in modelling its effect still produce the largest residuals between observations and present-day geomagnetic field models. A lot of progress has been achieved so far, but there are still open issues like the characteristics of the partial ring current. Other currents discussed are those flowing in the magnetospheric tail. Also their magnetic contribution at LEO orbits is non-negligible. Treating them as an independent source is a more recent development, which has cured some of the problems in geomagnetic field modelling. Unfortunately there is no index available for characterizing the tail current intensity. Here we propose an approach that may help to properly quantify the magnetic contribution from the tail current for geomagnetic field modelling. Some open questions that require further investigation are mentioned at the end.

  13. The last gasp of Dark Matter effective theory

    International Nuclear Information System (INIS)

    Bruggisser, Sebastian; Riva, Francesco; Urbano, Alfredo

    2016-07-01

    We discuss an interesting class of models, based on strongly coupled Dark Matter (DM), where sizable effects can be expected in LHC missing energy (MET) searches, compatibly with a large separation of scales. In this case, an effective field theory (EFT) is appropriate (and sometimes necessary) to describe the most relevant interactions at the LHC. The selection rules implied by the structure of the new strong dynamics shape the EFT in an unusual way, revealing the importance of higher-derivative interactions previously ignored. We compare indications from relic density and direct detection experiments with consistent LHC constraints, and asses the relative importance of the latter. Our analysis provides an interesting and well-motivated scenario to model MET at the LHC in terms of a handful of parameters.

  14. The last gasp of Dark Matter effective theory

    Energy Technology Data Exchange (ETDEWEB)

    Bruggisser, Sebastian [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Riva, Francesco; Urbano, Alfredo [CERN, Geneva (Switzerland). Theoretical Physics Dept.

    2016-07-15

    We discuss an interesting class of models, based on strongly coupled Dark Matter (DM), where sizable effects can be expected in LHC missing energy (MET) searches, compatibly with a large separation of scales. In this case, an effective field theory (EFT) is appropriate (and sometimes necessary) to describe the most relevant interactions at the LHC. The selection rules implied by the structure of the new strong dynamics shape the EFT in an unusual way, revealing the importance of higher-derivative interactions previously ignored. We compare indications from relic density and direct detection experiments with consistent LHC constraints, and asses the relative importance of the latter. Our analysis provides an interesting and well-motivated scenario to model MET at the LHC in terms of a handful of parameters.

  15. The Last Gasp of Dark Matter Effective Theory

    CERN Document Server

    Bruggisser, Sebastian; Urbano, Alfredo

    2016-11-10

    We discuss an interesting class of models, based on strongly coupled Dark Matter (DM), where sizable effects can be expected in LHC missing energy (MET) searches, compatibly with a large separation of scales. In this case, an effective field theory (EFT) is appropriate (and sometimes necessary) to describe the most relevant interactions at the LHC. The selection rules implied by the structure of the new strong dynamics shape the EFT in an unusual way, revealing the importance of higher-derivative interactions previously ignored. We compare indications from relic density and direct detection experiments with consistent LHC constraints, and asses the relative importance of the latter. Our analysis provides an interesting and well-motivated scenario to model MET at the LHC in terms of a handful of parameters.

  16. Effect of the Earth's gravitational field on the detection of gravitational waves

    International Nuclear Information System (INIS)

    Denisov, V.I.; Eliseev, V.A.

    1988-01-01

    We consider the laboratory detection of high-frequency gravitational waves in theories of gravitation based on a pseudo-Euclidean space-time. We analyze the effects due to the Earth's gravitational field on the propagation velocities of gravitational and electromagnetic waves in these theories. Experiments to test the predictions of this class of theories are discussed

  17. Effect of the diatomaceous earth in the soil chemical properties in corn crops (Zea mays L.

    Directory of Open Access Journals (Sweden)

    Lucia Fabila Martínez

    2013-10-01

    Full Text Available This study was developed out of the need to provide products and services intended for the field that meet the nutritional needs of plants without implicating environmental damage by means of chemical fertilizers and insecticides. The study assessed the fertilizer effect of two diatomaceous earth and a liquid fertilizer to corroborate empirical evidence of several producers who used a commercial product based on the study`s materials and achieved higher levels of performance in different crops. A sample of the experimental area was carried out before establishing the crop after its completion. Two commercial diatomaceous earth identified as 289 and 400 P produced by International Celite, were assessed at two concentrations 20 kg ha-1 and 40 kg ha-1 and 18 kg ha-1 and 36 kg ha-1 res­pectively, and a organic liquid fertilizer (FOL at doses of 2 L ha-1 and 4 L ha-1 was considered as control soil sample taken before the application of treatments. The experimental design used in the field for the application of the treatments was randomized complete block (DBA with 5 repetitions. The test plant was the corn hybrid HC8. The variables evaluated in the soil throudgh laboratory analysis were: physical properties of texture and bulk density (BD, and chemical pH, organic carbon (OC, organic matter (OM, electrical conductivity (EC, cation exchange capacity (CIC, nitrogen (N, phosphorus (P, potassium (K, calcium (Ca, magnesium (Mg and sodium (Na. The results were analyzed under a ANOVA and Tukey test for comparison of means for treatment, using the JMP statistical package. Laboratory results indicated that the­re were changes in the chemical characteristics of the soil between the control and treatments in the majority of the chemical characteristics analyzed (pH, CO, MO, N, P, K, Ca, Mg and Na. However statistically and under a statistical significance of 5%, differences were only observed in the properties of CO, MO, CE, N, K and Na.  

  18. The effect of gamma irradiation on the digestibility of organic matter of poultry excreta (In vitro)

    International Nuclear Information System (INIS)

    Al-Masri, M.R.

    1993-07-01

    The changes in the digestibility of dry matter and organic matter by enzyme (in vitro) for two types of the excreta of laying hens were studied. In type I, excreta were dried at 170-180 C for 10 minutes whereas in type II dried at 55-60 C for several days. Each type was divided into two parts, the first stored for 3 months with the control. The second part was irradiated by gamma irradiation at 100 KGy and stored for 3 months with the control. The results indicated that there was significant (0.05) difference in the digestibility of dry matter and organic matter and the percentage of crude fibre between samples and the control for the types I and II before and after storage. The dry matter digestibility for types I and II increased by 7%, and the organic matter digestibility increased by 17% for type I and by 11% for type II before and after storage. The increase in the digestibility of dry matter and organic matter is attributed to the decrease in crude fibre obtained by irradiation. The storage of excreta after drying has no effects on the rate of increase in the digestibility of dry matter and organic matter due to irradiation in both types (I and II). (author). 19 refs., 5 figs., 4 tabs

  19. Earth science big data at users' fingertips: the EarthServer Science Gateway Mobile

    Science.gov (United States)

    Barbera, Roberto; Bruno, Riccardo; Calanducci, Antonio; Fargetta, Marco; Pappalardo, Marco; Rundo, Francesco

    2014-05-01

    The EarthServer project (www.earthserver.eu), funded by the European Commission under its Seventh Framework Program, aims at establishing open access and ad-hoc analytics on extreme-size Earth Science data, based on and extending leading-edge Array Database technology. The core idea is to use database query languages as client/server interface to achieve barrier-free "mix & match" access to multi-source, any-size, multi-dimensional space-time data -- in short: "Big Earth Data Analytics" - based on the open standards of the Open Geospatial Consortium Web Coverage Processing Service (OGC WCPS) and the W3C XQuery. EarthServer combines both, thereby achieving a tight data/metadata integration. Further, the rasdaman Array Database System (www.rasdaman.com) is extended with further space-time coverage data types. On server side, highly effective optimizations - such as parallel and distributed query processing - ensure scalability to Exabyte volumes. In this contribution we will report on the EarthServer Science Gateway Mobile, an app for both iOS and Android-based devices that allows users to seamlessly access some of the EarthServer applications using SAML-based federated authentication and fine-grained authorisation mechanisms.

  20. On an effect of the interplanetary magnetic field sector structure on the upper Earth's ionosphere

    International Nuclear Information System (INIS)

    Kolomijtsev, O.P.; Livshits, M.A.; Soboleva, T.N.

    1985-01-01

    According to the data from vertical probing stations, changes are studied in the critical frequency and height of the ionosphere F2 layer after the Earth crosses the boundaries of the interplanetary magnetic field (IMF) sectors in the periods of equinox during decreases in the solar activity. A reversal of the IMF sign causes ionospheric effects, which in some cases are comparable, as to the value, with the effects observed in the presence of flares and strong geomagnetic perturbations. The IMF sector sign reversal is a key momentum, stimulating such changes in the Earth's magnetosphere state which result in the rearrangement of the ionosphere structure near the maximum of electron concentration on the planetary scale

  1. Direct search for dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Jonghee; /Fermilab

    2009-12-01

    Dark matter is hypothetical matter which does not interact with electromagnetic radiation. The existence of dark matter is only inferred from gravitational effects of astrophysical observations to explain the missing mass component of the Universe. Weakly Interacting Massive Particles are currently the most popular candidate to explain the missing mass component. I review the current status of experimental searches of dark matter through direct detection using terrestrial detectors.

  2. Transverse and Longitudinal Doppler Effects of the Sunbeam Spectra and Earth-Self Rotation and Orbital Velocities, the Mass of the Sun and Others

    OpenAIRE

    Nam, Sang Boo

    2009-01-01

    The transverse and longitudinal Doppler effects of the sunbeam spectra are shown to result in the earth parameters such as the earth-self rotation and revolution velocities, the earth orbit semi-major axis, the earth orbital angular momentum, the earth axial tilt, the earth orbit eccentricity, the local latitude and the mass of the sun. The sunbeam global positioning scheme is realized, including the earth orbital position. PACS numbers: 91.10.Fc, 95.10.Km, 91.10.Da, 91.10.Jf.

  3. Tensor Fermi liquid parameters in nuclear matter from chiral effective field theory

    Science.gov (United States)

    Holt, J. W.; Kaiser, N.; Whitehead, T. R.

    2018-05-01

    We compute from chiral two- and three-body forces the complete quasiparticle interaction in symmetric nuclear matter up to twice nuclear matter saturation density. Second-order perturbative contributions that account for Pauli blocking and medium polarization are included, allowing for an exploration of the full set of central and noncentral operator structures permitted by symmetries and the long-wavelength limit. At the Hartree-Fock level, the next-to-next-to-leading order three-nucleon force contributes to all noncentral interactions, and their strengths grow approximately linearly with the nucleon density up to that of saturated nuclear matter. Three-body forces are shown to enhance the already strong proton-neutron effective tensor interaction, while the corresponding like-particle tensor force remains small. We also find a large isovector cross-vector interaction but small center-of-mass tensor interactions in the isoscalar and isovector channels. The convergence of the expansion of the noncentral quasiparticle interaction in Landau parameters and Legendre polynomials is studied in detail.

  4. Dark matter in the universe

    International Nuclear Information System (INIS)

    Kormendy, J.; Knapp, G.R.

    1987-01-01

    Until recently little more was known than that dark matter appears to exist; there was little systematic information about its properties. Only in the past several years was progress made to the point where dark matter density distributions can be measured. For example, with accurate rotation curves extending over large ranges in radius, decomposing the effects of visible and dark matter to measure dark matter density profiles can be tried. Some regularities in dark matter behaviour have already turned up. This volume includes review and invited papers, poster papers, and the two general discussions. (Auth.)

  5. Gravitational mass of relativistic matter and antimatter

    Science.gov (United States)

    Kalaydzhyan, Tigran

    2015-12-01

    The universality of free fall, the weak equivalence principle (WEP), is a cornerstone of the general theory of relativity, the most precise theory of gravity confirmed in all experiments up to date. The WEP states the equivalence of the inertial, m, and gravitational, mg, masses and was tested in numerous occasions with normal matter at relatively low energies. However, there is no confirmation for the matter and antimatter at high energies. For the antimatter the situation is even less clear - current direct observations of trapped antihydrogen suggest the limits - 65 antigravity phenomenon, i.e. repulsion of the antimatter by Earth. Here we demonstrate an indirect bound 0.96 antigravity. By considering the absolute potential of the Local Supercluster (LS), we also predict the bounds 1 - 4 ×10-7

  6. Linking white matter and deep gray matter alterations in premanifest Huntington disease

    Directory of Open Access Journals (Sweden)

    Andreia V. Faria

    2016-01-01

    Full Text Available Huntington disease (HD is a fatal progressive neurodegenerative disorder for which only symptomatic treatment is available. A better understanding of the pathology, and identification of biomarkers will facilitate the development of disease-modifying treatments. HD is potentially a good model of a neurodegenerative disease for development of biomarkers because it is an autosomal-dominant disease with complete penetrance, caused by a single gene mutation, in which the neurodegenerative process can be assessed many years before onset of signs and symptoms of manifest disease. Previous MRI studies have detected abnormalities in gray and white matter starting in premanifest stages. However, the understanding of how these abnormalities are related, both in time and space, is still incomplete. In this study, we combined deep gray matter shape diffeomorphometry and white matter DTI analysis in order to provide a better mapping of pathology in the deep gray matter and subcortical white matter in premanifest HD. We used 296 MRI scans from the PREDICT-HD database. Atrophy in the deep gray matter, thalamus, hippocampus, and nucleus accumbens was analyzed by surface based morphometry, and while white matter abnormalities were analyzed in (i regions of interest surrounding these structures, using (ii tractography-based analysis, and using (iii whole brain atlas-based analysis. We detected atrophy in the deep gray matter, particularly in putamen, from early premanifest stages. The atrophy was greater both in extent and effect size in cases with longer exposure to the effects of the CAG expansion mutation (as assessed by greater CAP-scores, and preceded detectible abnormalities in the white matter. Near the predicted onset of manifest HD, the MD increase was widespread, with highest indices in the deep and posterior white matter. This type of in-vivo macroscopic mapping of HD brain abnormalities can potentially indicate when and where therapeutics could be

  7. HfO2 - rare earth oxide systems in the region with high content of rare earth oxide

    International Nuclear Information System (INIS)

    Shevchenko, A.V.; Lopato, L.M.

    1982-01-01

    Using the methods of annealing and hardenings (10 2 -10 4 deg/s cooling rate) and differential thermal analysis elements of state diagrams of HfO 2 - rare earth oxide (rare earths-La, Pr, Nd, Sm, Gd, Tb, Dy, Y, Er, Yb, Lu, Sc) systems from 1800 deg C up to melting in the range of 60-100 mol% rare earth oxide concentration were constructed. Regularities of HfQ 2 addition effect on high-temperature polymorphic transformations of rare earth oxides were studied. Results of investigation were discussed from viewpoint of crystal chemistry

  8. Effects of rare earth oxide nanoparticles on root elongation of plants.

    Science.gov (United States)

    Ma, Yuhui; Kuang, Linglin; He, Xiao; Bai, Wei; Ding, Yayun; Zhang, Zhiyong; Zhao, Yuliang; Chai, Zhifang

    2010-01-01

    The phytotoxicity of four rare earth oxide nanoparticles, nano-CeO(2), nano-La(2)O(3), nano-Gd(2)O(3) and nano-Yb(2)O(3) on seven higher plant species (radish, rape, tomato, lettuce, wheat, cabbage, and cucumber) were investigated in the present study by means of root elongation experiments. Their effects on root growth varied greatly between different nanoparticles and plant species. A suspension of 2000 mg L(-1) nano-CeO(2) had no effect on the root elongation of six plants, except lettuce. On the contrary, 2000 mg L(-1) suspensions of nano-La(2)O(3), nano-Gd(2)O(3) and nano-Yb(2)O(3) severely inhibited the root elongation of all the seven species. Inhibitory effects of nano-La(2)O(3), nano-Gd(2)O(3), and nano-Yb(2)O(3) also differed in the different growth process of plants. For wheat, the inhibition mainly took place during the seed incubation process, while lettuce and rape were inhibited on both seed soaking and incubation process. The fifty percent inhibitory concentrations (IC(50)) for rape were about 40 mg L(-1) of nano-La(2)O(3), 20mg L(-1) of nano-Gd(2)O(3), and 70 mg L(-1) of nano-Yb(2)O(3), respectively. In the concentration ranges used in this study, the RE(3+) ion released from the nanoparticles had negligible effects on the root elongation. These results are helpful in understanding phytotoxicity of rare earth oxide nanoparticles. Copyright 2009 Elsevier Ltd. All rights reserved.

  9. The effect of earth tides as observed in seismo-electromagnetic precursory signals

    Directory of Open Access Journals (Sweden)

    M. Hayakawa

    2009-10-01

    Full Text Available Studies on the effect of earth tides in triggering earthquakes (EQs had a great progress in recent years, which has provided convincing evidence of earth tides in EQ triggering. On the other hand, there have been accumulated a lot of evidences on the presence of seismogenic electromagnetic effects (such as ULF electromagnetic emissions from the lithosphere, ionospheric perturbations as detected by subionospheric VLF/LF propagation, etc.. Since the initial agent of these seismogenic electromagnetic effects is obviously due to some mechanical action around the EQ focal zone, the tidal effect as seen in EQ sequence should appear also in seismo-electromagnetic phenomena. Based on this expectation we have studied the tidal effect in different seismogenic phenomena, and have found that lithospheric ULF emissions exhibit a clear maximum-minimum-maximum pattern synchronized with the lunar phase of the EQ during several months before the EQ. As for VLF/LF propagation anomaly representing the lower ionospheric perturbation, we have found the tidal modulation very similar to ULF emissions, but less clear, and also there are some differences from the ULF case (such as occasional shift with respect to the lunar phase and/or the presence of higher frequency modulation, etc.. These findings are indicative that those electromagnetic phenomena reported to be in possible association with an EQ are really related with any preparatory phase of an EQ. This kind of study would be a bridge between the seismology and our seismo-electromagnetic study.

  10. Hydric characterisation of rammed earth samples for different lime concentrations

    Science.gov (United States)

    Soudani, Lucile; Fabbri, Antonin; Woloszyn, Monika; Grillet, Anne-Cécile; Morel, Jean-Claude

    2018-04-01

    The rehabilitation of ancient rammed earth houses, as well as the use of earthen materials in modern constructions, are a growing matter of concern, especially in area such as Rhône-Alpes, France, where 40% of old constructions are in rammed earth. A current pathology observed for this type of construction is related to the rising damps, for which the water from the ground is absorbed by the wall. This situation leads to a very saturated state. As it has been proven that the compressive strength is altered by the presence of water in the pores, a better understanding on high relative humidity range is necessary to be able to predict the mechanical behavior of buildings and thus ensure a better risk assessment. The present study describes experimental results of the water uptake experiments and moisture storage at high relative humidities.

  11. Many body effects in nuclear matter QCD sum rules

    Science.gov (United States)

    Drukarev, E. G.; Ryskin, M. G.; Sadovnikova, V. A.

    2017-12-01

    We calculate the single-particle nucleon characteristics in symmetric nuclear matter with inclusion of the 3N and 4N interactions. We calculated the contribution of the 3N interactions earlier, now we add that of the 4N ones. The contribution of the 4N forces to nucleon self energies is expressed in terms of the nonlocal scalar condensate (d = 3) and of the configurations of the vector-scalar and the scalar-scalar quark condensates (d = 6) in which two diquark operators act on two different nucleons of the matter.These four-quark condensates are obtained in the model-independent way. The density dependence of the nucleon effective mass, of the vector self energy and of the single-particle potential energy are obtained. We traced the dependence of the nucleon characteristics on the actual value of the pion-nucleon sigma term. We obtained also the nucleon characteristics in terms of the quasifree nucleons, with the noninteracting nucleons surrounded by their pion clouds as the starting point. This approach leads to strict hierarchy of the many body forces.

  12. Stars of strange matter

    International Nuclear Information System (INIS)

    Bethe, H.A.; Brown, G.E.; Cooperstein, J.

    1987-01-01

    We investigate suggestions that quark matter with strangeness per baryon of order unity may be stable. We model this matter at nuclear matter densities as a gas of close packed Λ-particles. From the known mass of the Λ-particle we obtain an estimate of the energy and chemical potential of strange matter at nuclear densities. These are sufficiently high to preclude any phase transition from neutron matter to strange matter in the region near nucleon matter density. Including effects from gluon exchange phenomenologically, we investigate higher densities, consistently making approximations which underestimate the density of transition. In this way we find a transition density ρ tr > or approx.7ρ 0 , where ρ 0 is nuclear matter density. This is not far from the maximum density in the center of the most massive neutron stars that can be constructed. Since we have underestimated ρ tr and still find it to be ∝7ρ 0 , we do not believe that the transition from neutron to quark matter is likely in neutron stars. Moreover, measured masses of observed neutron stars are ≅1.4 M sun , where M sun is the solar mass. For such masses, the central (maximum) density is ρ c 0 . Transition to quark matter is certainly excluded for these densities. (orig.)

  13. Necessity of using heterogeneous ellipsoidal Earth model with terrain to calculate co-seismic effect

    Science.gov (United States)

    Cheng, Huihong; Zhang, Bei; Zhang, Huai; Huang, Luyuan; Qu, Wulin; Shi, Yaolin

    2016-04-01

    Co-seismic deformation and stress changes, which reflect the elasticity of the earth, are very important in the earthquake dynamics, and also to other issues, such as the evaluation of the seismic risk, fracture process and triggering of earthquake. Lots of scholars have researched the dislocation theory and co-seismic deformation and obtained the half-space homogeneous model, half-space stratified model, spherical stratified model, and so on. Especially, models of Okada (1992) and Wang (2003, 2006) are widely applied in the research of calculating co-seismic and post-seismic effects. However, since both semi-infinite space model and layered model do not take the role of the earth curvature or heterogeneity or topography into consideration, there are large errors in calculating the co-seismic displacement of a great earthquake in its impacted area. Meanwhile, the computational methods of calculating the co-seismic strain and stress are different between spherical model and plane model. Here, we adopted the finite element method which could well deal with the complex characteristics (such as anisotropy, discontinuities) of rock and different conditions. We use the mash adaptive technique to automatically encrypt the mesh at the fault and adopt the equivalent volume force replace the dislocation source, which can avoid the difficulty in handling discontinuity surface with conventional (Zhang et al., 2015). We constructed an earth model that included earth's layered structure and curvature, the upper boundary was set as a free surface and the core-mantle boundary was set under buoyancy forces. Firstly, based on the precision requirement, we take a testing model - - a strike-slip fault (the length of fault is 500km and the width is 50km, and the slippage is 10m) for example. Because of the curvature of the Earth, some errors certainly occur in plane coordinates just as previous studies (Dong et al., 2014; Sun et al., 2012). However, we also found that: 1) the co

  14. The effect of acid rain stress on membrane protective system of spinach and the conservation of rare earth elements

    International Nuclear Information System (INIS)

    Chongling, Y; Yetang, H.

    1998-01-01

    Full text: Based on pot experiments, the effect of acid rain stress on membrane protective system of spinach and the effect of rare earth elements has been studied. The results showed, stress of acid rain resulted in decrease of over all level of superoxide dismutase activity, catalase activity and increase of peroxidase (POD) activity. After being treated by rare earth elements, the overall level of superoxide dismutase activity and catalase activity were increased and the peak value of activity variation curve moved toward to the direction of higher acidity. POD activity increased slightly, comparing with the plants that hadn't been treated by rare earth elements under same acid rain condition; the three important enzymes of membrane protective system could be kept on a relatively stable level. It was clear that in relative lower acidity condition, rare earth elements can reduce the impact of acid rain on the membrane protective system

  15. Urban tree effects on fine particulate matter and human health

    Science.gov (United States)

    David J. Nowak

    2014-01-01

    Overall, city trees reduce particulate matter and provide substantial health benefits; but under certain conditions, they can locally increase particulate matter concentrations. Urban foresters need to understand how trees affect particulate matter so they can select proper species and create appropriate designs to improve air quality. This article details trees'...

  16. Effects of Brown-Rho scalings in nuclear matter, neutron stars and finite nuclei

    Science.gov (United States)

    Kuo, T. T. S.; Dong, Huan

    2011-01-01

    We have carried out calculations for nuclear matter, neutron stars and finite nuclei using NN potentials with and without the medium-dependent modifications based on the Brown-Rho (BR) scalings. Using the Vlow-k low-momentum interactions derived from such potentials, the equations of state (EOS) for symmetric and asymmetric nuclear matter, for densities up to ~ 5ρ0, are calculated using a RPA method where the particle-particle hole-hole ring diagrams are summed to all orders. The medium effects from both a linear BR scaling (BR1) and a non-linear one (BR2) are considered, and they both are essential for our EOSs to reproduce the nuclear matter saturation properties. For densities ρ below ρ0, results from BR1 and BR2 are close to each other. For higher densities, the EOS given by BR2 is more desirable and is well reproduced by that given by the interaction (Vlow-k+TBF) where Vlow-k is the unsealed low-momentum interaction and TBF is an empirical Skyrme three-body force. The moment of inertia of neutron stars is ~ 60 and ~ 25Modotkm2 respectively with and without the inclusion of the above BR2 medium effects. Effects from the BR scaling are important for the long half-life, ~ 5000yrs, of the 14C - 14N β-decay.

  17. How do we know about Earth's history? Constructing the story of Earth's geologic history by collecting and interpreting evidence based scenarios.

    Science.gov (United States)

    Ruthford, Steven; DeBari, Susan; Linneman, Scott; Boriss, Miguel; Chesbrough, John; Holmes, Randall; Thibault, Allison

    2013-04-01

    Beginning in 2003, faculty from Western Washington University, Skagit Valley Community College, local public school teachers, and area tribal college members created an innovative, inquiry based undergraduate geology curriculum. The curriculum, titled "Energy and Matter in Earth's Systems," was supported through various grants and partnerships, including Math and Science Partnership and Noyce Teacher Scholarship grants from the National Science Foundation. During 2011, the authors wrote a geologic time unit for the curriculum. The unit is titled, "How Do We Know About Earth's History?" and has students actively investigate the concepts related to geologic time and methods for determining age. Starting with reflection and assessment of personal misconceptions called "Initial Ideas," students organize a series of events into a timeline. The unit then focuses on the concepts of relative dating, biostratigraphy, and historical attempts at absolute dating, including uniformitarianism, catastrophism, Halley and Joly's Salinity hypothesis, and Kelvin's Heat Loss model. With limited lecture and text, students then dive into current understandings of the age of the Earth, which include radioactive decay rates and radiometric dating. Finally, using their newfound understanding, students investigate a number of real world scenarios and create a timeline of events related to the geologic history of the Earth. The unit concludes with activities that reinforce the Earth's absolute age and direct students to summarize what they have learned by reorganizing the timeline from the "Initial Ideas" and sharing with the class. This presentation will include the lesson materials and findings from one activity titled, "The Earth's Story." The activity is located midway through the unit and begins with reflection on the question, "What are the major events in the Earth's history and when did they happen?" Students are directed to revisit the timeline of events from the "Initial Ideas

  18. Constraining Secluded Dark Matter models with the public data from the 79-string IceCube search for dark matter in the Sun

    Energy Technology Data Exchange (ETDEWEB)

    Ardid, M.; Felis, I.; Martínez-Mora, J.A. [Institut d' Investigació per a la Gestió Integrada de les Zones Costaneres (IGIC), Universitat Politècnica de València, C/Paranimf 1, 46730 Gandia (Spain); Herrero, A., E-mail: mardid@fis.upv.es, E-mail: ivfeen@upv.es, E-mail: aherrero@mat.upv.es, E-mail: jmmora@fis.upv.es [Institut de Matemàtica Multidisciplinar, Universitat Politècnica de València, Camí de Vera s/n, 46022 València (Spain)

    2017-04-01

    The 79-string IceCube search for dark matter in the Sun public data is used to test Secluded Dark Matter models. No significant excess over background is observed and constraints on the parameters of the models are derived. Moreover, the search is also used to constrain the dark photon model in the region of the parameter space with dark photon masses between 0.22 and ∼ 1 GeV and a kinetic mixing parameter ε ∼ 10{sup −9}, which remains unconstrained. These are the first constraints of dark photons from neutrino telescopes. It is expected that neutrino telescopes will be efficient tools to test dark photons by means of different searches in the Sun, Earth and Galactic Center, which could complement constraints from direct detection, accelerators, astrophysics and indirect detection with other messengers, such as gamma rays or antiparticles.

  19. Effects of mineral matters on evolution of sulfur-containing gases in pyrolysis and hydropyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H.; Li, B.; Zhang, B. [Institute of Coal Chemistry, Chinese Academy of Sciences, Taiyuan (China). State Key Lab. of Coal Conversion

    1998-07-01

    The evolution of sulfur-containing gases were investigated using two Chinese coals with their de-ash and de-pyrite forms in pyrolysis and hydropyrolysis. Mineral matter can not only return H{sub 2}S produced in pyrolysis and hydropyrolysis, but also catalyse hydrodesulfurization and reduce COS formation. Secondary reactions markedly influence COS formation. Mineral matter can reduce CH{sub 3}SH formation, and pyrite shows positive effects on CH{sub 3}SH formation. 7 refs., 6 figs., 1 tab.

  20. Radiative properties of astrophysical matter: a quest to reproduce astrophysical conditions on earth

    International Nuclear Information System (INIS)

    Bailey, James E.

    2010-01-01

    Experiments in terrestrial laboratories can be used to evaluate the physical models that interpret astronomical observations. The properties of matter in astrophysical objects are essential components of these models, but terrestrial laboratories struggle to reproduce the extreme conditions that often exist. Megajoule-class DOE/NNSA facilities such as the National Ignition Facility and Z can create unprecedented amounts of matter at extreme conditions, providing new capabilities to test astrophysical models with high accuracy. Experiments at these large facilities are challenging, and access is very competitive. However, the cylindrically-symmetric Z source emits radiation in all directions, enabling multiple physics experiments to be driven with a single Z discharge. This helps ameliorate access limitations. This article describes research efforts under way at Sandia National Laboratories Z facility investigating radiation transport through stellar interior matter, population kinetics of atoms exposed to the intense radiation emitted by accretion powered objects, and spectral line formation in white dwarf (WD) photospheres. Opacity quantifies the absorption of radiation by matter and strongly influences stellar structure and evolution, since radiation dominates energy transport deep inside stars. Opacity models have become highly sophisticated, but laboratory tests at the conditions existing inside stars have not been possible - until now. Z research is presently focused on measuring iron absorption at conditions relevant to the base of the solar convection zone, where the electron temperature and density are 190 eV and 9 x 10 22 e/cc, respectively. Creating these conditions in a sample that is sufficiently large, long-lived, and uniform is extraordinarily challenging. A source of radiation that streams through the relatively-large samples can produce volumetric heating and thus, uniform conditions, but to achieve high temperatures a strong source is required. Z

  1. Make dark matter charged again

    Energy Technology Data Exchange (ETDEWEB)

    Agrawal, Prateek; Cyr-Racine, Francis-Yan; Randall, Lisa; Scholtz, Jakub, E-mail: prateekagrawal@fas.harvard.edu, E-mail: fcyrraci@physics.harvard.edu, E-mail: randall@physics.harvard.edu, E-mail: jscholtz@physics.harvard.edu [Department of Physics, Harvard University, Cambridge, MA 02138 (United States)

    2017-05-01

    We revisit constraints on dark matter that is charged under a U(1) gauge group in the dark sector, decoupled from Standard Model forces. We find that the strongest constraints in the literature are subject to a number of mitigating factors. For instance, the naive dark matter thermalization timescale in halos is corrected by saturation effects that slow down isotropization for modest ellipticities. The weakened bounds uncover interesting parameter space, making models with weak-scale charged dark matter viable, even with electromagnetic strength interaction. This also leads to the intriguing possibility that dark matter self-interactions within small dwarf galaxies are extremely large, a relatively unexplored regime in current simulations. Such strong interactions suppress heat transfer over scales larger than the dark matter mean free path, inducing a dynamical cutoff length scale above which the system appears to have only feeble interactions. These effects must be taken into account to assess the viability of darkly-charged dark matter. Future analyses and measurements should probe a promising region of parameter space for this model.

  2. Strange matter in compact stars

    Directory of Open Access Journals (Sweden)

    Klähn Thomas

    2018-01-01

    Full Text Available We discuss possible scenarios for the existence of strange matter in compact stars. The appearance of hyperons leads to a hyperon puzzle in ab-initio approaches based on effective baryon-baryon potentials but is not a severe problem in relativistic mean field models. In general, the puzzle can be resolved in a natural way if hadronic matter gets stiffened at supersaturation densities, an effect based on the quark Pauli quenching between hadrons. We explain the conflict between the necessity to implement dynamical chiral symmetry breaking into a model description and the conditions for the appearance of absolutely stable strange quark matter that require both, approximately masslessness of quarks and a mechanism of confinement. The role of strangeness in compact stars (hadronic or quark matter realizations remains unsettled. It is not excluded that strangeness plays no role in compact stars at all. To answer the question whether the case of absolutely stable strange quark matter can be excluded on theoretical grounds requires an understanding of dense matter that we have not yet reached.

  3. Strange matter in compact stars

    Science.gov (United States)

    Klähn, Thomas; Blaschke, David B.

    2018-02-01

    We discuss possible scenarios for the existence of strange matter in compact stars. The appearance of hyperons leads to a hyperon puzzle in ab-initio approaches based on effective baryon-baryon potentials but is not a severe problem in relativistic mean field models. In general, the puzzle can be resolved in a natural way if hadronic matter gets stiffened at supersaturation densities, an effect based on the quark Pauli quenching between hadrons. We explain the conflict between the necessity to implement dynamical chiral symmetry breaking into a model description and the conditions for the appearance of absolutely stable strange quark matter that require both, approximately masslessness of quarks and a mechanism of confinement. The role of strangeness in compact stars (hadronic or quark matter realizations) remains unsettled. It is not excluded that strangeness plays no role in compact stars at all. To answer the question whether the case of absolutely stable strange quark matter can be excluded on theoretical grounds requires an understanding of dense matter that we have not yet reached.

  4. The Near-Earth Space Radiation Environment

    Science.gov (United States)

    Xapsos, Michael

    2008-01-01

    This viewgraph presentation reviews the effects of the Near-Earth space radiation environment on NASA missions. Included in this presentation is a review of The Earth s Trapped Radiation Environment, Solar Particle Events, Galactic Cosmic Rays and Comparison to Accelerator Facilities.

  5. Compact bifluid hybrid stars: hadronic matter mixed with self-interacting fermionic asymmetric dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Mukhopadhyay, Somnath; Basu, D.N. [HBNI, Variable Energy Cyclotron Centre, Kolkata (India); Atta, Debasis [HBNI, Variable Energy Cyclotron Centre, Kolkata (India); Government General Degree College, West Bengal (India); Imam, Kouser [HBNI, Variable Energy Cyclotron Centre, Kolkata (India); Aliah University, Department of Physics, Kolkata (India); Samanta, C. [Virginia Military Institute, Department of Physics and Astronomy, Lexington, VA (United States)

    2017-07-15

    The masses and radii of non-rotating and rotating configurations of pure hadronic stars mixed with self-interacting fermionic asymmetric dark matter are calculated within the two-fluid formalism of stellar structure equations in general relativity. The Equation of State (EoS) of nuclear matter is obtained from the density dependent M3Y effective nucleon-nucleon interaction. We consider the dark matter particle mass of 1 GeV. The EoS of self-interacting dark matter is taken from two-body repulsive interactions of the scale of strong interactions. We explore the conditions of equal and different rotational frequencies of nuclear matter and dark matter and find that the maximum mass of differentially rotating stars with self-interacting dark matter to be ∝1.94 M {sub CircleDot} with radius ∝10.4 km. (orig.)

  6. Dark matter versus Mach's principle.

    Science.gov (United States)

    von Borzeszkowski, H.-H.; Treder, H.-J.

    1998-02-01

    Empirical and theoretical evidence show that the astrophysical problem of dark matter might be solved by a theory of Einstein-Mayer type. In this theory up to global Lorentz rotations the reference system is determined by the motion of cosmic matter. Thus one is led to a "Riemannian space with teleparallelism" realizing a geometric version of the Mach-Einstein doctrine. The field equations of this gravitational theory contain hidden matter terms where the existence of hidden matter is inferred safely from its gravitational effects. It is argued that in the nonrelativistic mechanical approximation they provide an inertia-free mechanics where the inertial mass of a body is induced by the gravitational action of the comic masses. Interpreted form the Newtonian point of view this mechanics shows that the effective gravitational mass of astrophysical objects depends on r such that one expects the existence of dark matter.

  7. Comparison of solidification temperatures of different rare earth sesquioxides; effect of atmosphere

    International Nuclear Information System (INIS)

    Coutures, J.-P.; Verges, R.; Foex, M.

    1975-01-01

    The measurement of the solidification point of the rare earth sesquioxides shows anomalies for La 2 O 3 , Gd 2 O 3 , Lu 2 O 3 and allows to find the well known ceric group and yttric group. The effects of the atmosphere on the refractory character are generally low. An interpretation in order to explain the observed changes, is proposed [fr

  8. Preparing rare earth-silicon-iron-aluminum alloys

    International Nuclear Information System (INIS)

    Marchant, J.D.; Morrice, E.; Herve, B.P.; Wong, M.M.

    1980-01-01

    As part of its mission to assure the maximum recovery and use of the Nation's mineral resources, the Bureau of Mines, investigated an improved procedure for producing rare earth-silicon alloys. For example, a charge consisting of 681 grams of mixed rare-earth oxides, 309 grams of ferrosilicon (75 wt-pct Si), and 182 grams of aluminum metal along with a flux consisting of 681 grams of CaO and 45 grams of MgO was reacted at 1500 0 C in an induction furnace. Good slag-metal separation was achieved. The alloy product contained, in weight-percent, 53 RE, 28 Si, 11 Fe, and 4 Al with a rare earth recovery of 80 pct. In current industrial practice rare earth recoveries are usually about 60 pct in alloy products that contain approximately 30 wt-pct each of rare earths and silicon. Metallurgical evaluations showed the alloys prepared in this investigation to be as effective in controlling the detrimental effect of sulfur in steel and cast iron as the commercial rare earth-silicon-iron alloys presently used in the steel industry

  9. Reheating effects in the matter power spectrum and implications for substructure

    International Nuclear Information System (INIS)

    Erickcek, Adrienne L.; Sigurdson, Kris

    2011-01-01

    The thermal and expansion history of the Universe before big bang nucleosynthesis is unknown. We investigate the evolution of cosmological perturbations through the transition from an early matter era to radiation domination. We treat reheating as the perturbative decay of an oscillating scalar field into relativistic plasma and cold dark matter. After reheating, we find that subhorizon perturbations in the decay-produced dark matter density are significantly enhanced, while subhorizon radiation perturbations are instead suppressed. If dark matter originates in the radiation bath after reheating, this suppression may be the primary cutoff in the matter power spectrum. Conversely, for dark matter produced nonthermally from scalar decay, enhanced perturbations can drive structure formation during the cosmic dark ages and dramatically increase the abundance of compact substructures. For low reheat temperatures, we find that as much as 50% of all dark matter is in microhalos with M > or approx. 0.1M + at z≅100, compared to a fraction of ∼10 -10 in the standard case. In this scenario, ultradense substructures may constitute a large fraction of dark matter in galaxies today.

  10. Matter-antimatter and matter-matter interactions at intermediate energies

    International Nuclear Information System (INIS)

    Santos, Antonio Carlos Fontes dos

    2002-01-01

    This article presents some of the recent experimental advances on the study on antimatter-matter and matter-matter interactions, and some of the subtle differences stimulated a great theoretical efforts for explanation of the results experimentally observed

  11. Neutron matter at next-to-next-to-next-to-leading order in chiral effective field theory.

    Science.gov (United States)

    Tews, I; Krüger, T; Hebeler, K; Schwenk, A

    2013-01-18

    Neutron matter presents a unique system for chiral effective field theory because all many-body forces among neutrons are predicted to next-to-next-to-next-to-leading order (N(3)LO). We present the first complete N(3)LO calculation of the neutron matter energy. This includes the subleading three-nucleon forces for the first time and all leading four-nucleon forces. We find relatively large contributions from N(3)LO three-nucleon forces. Our results provide constraints for neutron-rich matter in astrophysics with controlled theoretical uncertainties.

  12. The International Year of Planet Earth (2007-2009):Earth Sciences for Society

    Institute of Scientific and Technical Information of China (English)

    Eduardo F.J.de Mulder; Ted Nield; Edward Derbyshire

    2006-01-01

    Natural disasters like the 2004 tsunami bear graphic testimony to the Earth's incredible power. More effective use of geoscientific knowledge can save lives and protect property. Such knowledge also enables us to satisfy, in a sustainable manner,the growing need for Earth's resources by an expanding human population. Such knowledge is readily available in the practical experience and publications of some half a million Earth scientists all over the world, a professional community that is ready and willing to contribute to a safer, healthier and wealthier society if called upon by politicians and decision makers. Professional guidance by Earth scientists is available in many aspects of everyday life including, for example, identification of the best areas for urban expansion, sites to avoid for waste disposal, the location of new underground fresh water resources, and where certain toxic agents implicated in Earth-related diseases may be located, etc.The International Year of Planet Earth (2007-2009) aims to build on existing knowledge and make it more available for the improvement of everyday life, especially in the less developed countries, as expressed in the Year's subtitle: Earth sciences for Society. Ambitious outreach and science programmes constitute the backbone of the International Year, now politically endorsed by all 191 member states of the United Nations Organisation which has proclaimed 2008, the central year of the triennium, as the UN Year of Planet Earth. This paper describes who is behind the initiative,how it will work, and how the political process leading to United Nations proclamation proceeded. It also describes the financial and organisational aspects of the International Year, sets out the commitments necessary for the realization of the Year's ambitions by all nations, and explains how the raising of US$ 20 million will be approached.

  13. Perbandingan intensitas warna CPO dengan menggunakan Bleaching Earth (BE) dan Spent Bleaching Earth (SBE) di PT. SMART Tbk.

    OpenAIRE

    Aritonang, Dwi Christina

    2016-01-01

    Comparative studies have been conducted on the effect of bleaching earth quality bleachibility power on CPO (crude palm oil). by using the tool Lovibond Tintometer model of F in PT Smart Tbk Medan – Belawan.From experiments obtained initial color with the CPO 20R - 20Y after addition Bleaching Earth and spent bleaching earth with the CPO each - each 10,2R - 20Y and 17.3R - 20Y . The results showed that purification using Bleaching Earth better than the purification of Spent Bleaching Earh ...

  14. Suprathermal viscosity of dense matter

    International Nuclear Information System (INIS)

    Alford, Mark; Mahmoodifar, Simin; Schwenzer, Kai

    2010-01-01

    Motivated by the existence of unstable modes of compact stars that eventually grow large, we study the bulk viscosity of dense matter, taking into account non-linear effects arising in the large amplitude regime, where the deviation μ Δ of the chemical potentials from chemical equilibrium fulfills μ Δ > or approx. T. We find that this supra-thermal bulk viscosity can provide a potential mechanism for saturating unstable modes in compact stars since the viscosity is strongly enhanced. Our study confirms previous results on strange quark matter and shows that the suprathermal enhancement is even stronger in the case of hadronic matter. We also comment on the competition of different weak channels and the presence of suprathermal effects in various color superconducting phases of dense quark matter.

  15. Mycorrhizal associations of trees have different indirect effects on organic matter decomposition

    Science.gov (United States)

    Melanie K. Taylor; Richard A. Lankau; Nina Wurzburger; Franciska de Vries

    2016-01-01

    1. Organic matter decomposition is the main process by which carbon (C) is lost from terrestrialecosystems, and mycorrhizal associations of plants (i.e. arbuscular mycorrhizas (AM) and ectomycorrhizas(ECM)) may have different indirect effects on this loss pathway. AM and ECM plants differin the soil...

  16. An Earth-sized planet with an Earth-like density.

    Science.gov (United States)

    Pepe, Francesco; Cameron, Andrew Collier; Latham, David W; Molinari, Emilio; Udry, Stéphane; Bonomo, Aldo S; Buchhave, Lars A; Charbonneau, David; Cosentino, Rosario; Dressing, Courtney D; Dumusque, Xavier; Figueira, Pedro; Fiorenzano, Aldo F M; Gettel, Sara; Harutyunyan, Avet; Haywood, Raphaëlle D; Horne, Keith; Lopez-Morales, Mercedes; Lovis, Christophe; Malavolta, Luca; Mayor, Michel; Micela, Giusi; Motalebi, Fatemeh; Nascimbeni, Valerio; Phillips, David; Piotto, Giampaolo; Pollacco, Don; Queloz, Didier; Rice, Ken; Sasselov, Dimitar; Ségransan, Damien; Sozzetti, Alessandro; Szentgyorgyi, Andrew; Watson, Christopher A

    2013-11-21

    Recent analyses of data from the NASA Kepler spacecraft have established that planets with radii within 25 per cent of the Earth's (R Earth symbol) are commonplace throughout the Galaxy, orbiting at least 16.5 per cent of Sun-like stars. Because these studies were sensitive to the sizes of the planets but not their masses, the question remains whether these Earth-sized planets are indeed similar to the Earth in bulk composition. The smallest planets for which masses have been accurately determined are Kepler-10b (1.42 R Earth symbol) and Kepler-36b (1.49 R Earth symbol), which are both significantly larger than the Earth. Recently, the planet Kepler-78b was discovered and found to have a radius of only 1.16 R Earth symbol. Here we report that the mass of this planet is 1.86 Earth masses. The resulting mean density of the planet is 5.57 g cm(-3), which is similar to that of the Earth and implies a composition of iron and rock.

  17. Towards earth AntineutRino TomograpHy (EARTH)

    NARCIS (Netherlands)

    De Meijer, R. J.; Smit, F. D.; Brooks, F. D.; Fearick, R. W.; Wortche, H. J.; Mantovani, F.

    2006-01-01

    The programme Earth AntineutRino TomograpHy (EARTH) proposes to build ten underground facilities each hosting a telescope. Each telescope consists of many detector modules, to map the radiogenic heat sources deep in the interior of the Earth by utilising direction sensitive geoneutrino detection.

  18. Modelling the interaction of high energy ions with inert matter, living matter, and moving matter

    International Nuclear Information System (INIS)

    Beuve, Michael

    2007-01-01

    In this report for accreditation to supervise research (HDR), the author proposes a synthetic (and however relatively detailed) overview of his research works in the fields of physics and radiology. The first part addresses works in the field of interaction between ions and inert matter (Monte Carlo simulation of emission induced by ion-solid interaction, simulation by molecular dynamics of pulverization). The second part addresses the interaction between ions and living matter: research strategy, principle of the Local Effect Model (LEM) and influence of its main parameters, LEM experimental assessment, LEM theoretical analysis, role of the cell oxidizing and anti-oxidizing system. The next part addresses the interaction of ions with moving matter: research strategy, lung mechanics modelling and clinical assessments, chest wall mechanics, transformation of movements simulated in 4D scanner imagery

  19. Effect of rare earth ion Ce3+ on the lactate dehydrogenase isozyme patterns of six mouse organs

    International Nuclear Information System (INIS)

    Jiangyan, L.; Guojun, S.; Hengyi, L.; Yinhua, L.; Ting, W.; Yansheng, Y.

    1998-01-01

    Full text: Effect of rare earth ion Ce 3+ on the lactate dehydrogenase (LDH) isozyme patterns of six organs of mouse (heart, liver, kidney, muscle, stomach) were investigated by utilizing polyacrylamide gel electrophoresis (PAGE) methods. The results indicated: Ce 3+ not only can make some LDH bands disappear but also can induce some new bands. Under the action of Ce 3+ , the shades of some LDH bands were changed and the shade variations were different from organ to organ. In the muscle, it appeared the shade of LDH bands was related to the rare earth concentration in the feed. Rare earth can affect the muscle LDH patterns widely and apparently

  20. Effect of the kind of alkaline and rare earth ions on the structure of a glass rich in earth

    International Nuclear Information System (INIS)

    Quintas, Arnaud; Caurant, Daniel; Majerus, Odile; Lenoir, Marion; Dussossoy, Jean-Luc; Charpentier, Thibault; Neuville, Daniel R.; Gervais, C.

    2006-01-01

    In the framework of a structural study of a nuclear wastes containment glass of type alumino borosilicate and rich in rare earths, the influence of the kind of alkaline or rare earth ions is analyzed. For that, two glasses series have been prepared in which the Na + ion (respectively Ca 2+ ions) present in the standard composition is totally substituted by another alkaline ion Li + , K + , Rb + or Cs + (respectively another rare earth ion Mg 2+ , Sr 2+ or Ba 2+ ). These glasses, analyzed by optical absorption, Raman and 27 Al or 11 B NMR spectroscopies have revealed the strong impact of the kind of the modifying ion as well as the structure of the vitreous lattice (variation of the ratio BO 3 /BO 4 and local variations of the polymerization degree) than the local surroundings of the rare earth (decrease of the covalency degree of the bond Nd-O with the increase of the field force of the modifying ion). (O.M.)

  1. Effect of light assisted collisions on matter wave coherence in superradiant Bose-Einstein condensates

    DEFF Research Database (Denmark)

    Kampel, Nir Shlomo; Griesmaier, Axel Rudolf; Steenstrup, Mads Peter Hornbak

    2012-01-01

    We investigate experimentally the effects of light assisted collisions on the coherence between momentum states in Bose-Einstein condensates. The onset of superradiant Rayleigh scattering serves as a sensitive monitor for matter-wave coherence. A subtle interplay of binary and collective effects...

  2. Comparison of Elemental Mercury Oxidation Across Vanadium and Cerium Based Catalysts in Coal Combustion Flue Gas: Catalytic Performances and Particulate Matter Effects.

    Science.gov (United States)

    Wan, Qi; Yao, Qiang; Duan, Lei; Li, Xinghua; Zhang, Lei; Hao, Jiming

    2018-03-06

    This paper discussed the field test results of mercury oxidation activities over vanadium and cerium based catalysts in both coal-fired circulating fluidized bed boiler (CFBB) and chain grate boiler (CGB) flue gases. The characterizations of the catalysts and effects of flue gas components, specifically the particulate matter (PM) species, were also discussed. The catalytic performance results indicated that both catalysts exhibited mercury oxidation preference in CGB flue gas rather than in CFBB flue gas. Flue gas component studies before and after dust removal equipment implied that the mercury oxidation was well related to PM, together with gaseous components such as NO, SO 2 , and NH 3 . Further investigations demonstrated a negative PM concentration-induced effect on the mercury oxidation activity in the flue gases before the dust removal, which was attributed to the surface coverage by the large amount of PM. In addition, the PM concentrations in the flue gases after the dust removal failed in determining the mercury oxidation efficiency, wherein the presence of different chemical species in PM, such as elemental carbon (EC), organic carbon (OC) and alkali (earth) metals (Na, Mg, K, and Ca) in the flue gases dominated the catalytic oxidation of mercury.

  3. Mapping Near-Earth Hazards

    Science.gov (United States)

    Kohler, Susanna

    2016-06-01

    How can we hunt down all the near-Earth asteroids that are capable of posing a threat to us? A new study looks at whether the upcoming Large Synoptic Survey Telescope (LSST) is up to the job.Charting Nearby ThreatsLSST is an 8.4-m wide-survey telescope currently being built in Chile. When it goes online in 2022, it will spend the next ten years surveying our sky, mapping tens of billions of stars and galaxies, searching for signatures of dark energy and dark matter, and hunting for transient optical events like novae and supernovae. But in its scanning, LSST will also be looking for asteroids that approach near Earth.Cumulative number of near-Earth asteroids discovered over time, as of June 16, 2016. [NASA/JPL/Chamberlin]Near-Earth objects (NEOs) have the potential to be hazardous if they cross Earths path and are large enough to do significant damage when they impact Earth. Earths history is riddled with dangerous asteroid encounters, including the recent Chelyabinsk airburst in 2013, the encounter that caused the kilometer-sized Meteor Crater in Arizona, and the impact thought to contribute to the extinction of the dinosaurs.Recognizing the potential danger that NEOs can pose to Earth, Congress has tasked NASA with tracking down 90% of NEOs larger than 140 meters in diameter. With our current survey capabilities, we believe weve discovered roughly 25% of these NEOs thus far. Now a new study led by Tommy Grav (Planetary Science Institute) examines whether LSST will be able to complete this task.Absolute magnitude, H, of asynthetic NEO population. Though these NEOs are all larger than 140 m, they have a large spread in albedos. [Grav et al. 2016]Can LSST Help?Based on previous observations of NEOs and resulting predictions for NEO properties and orbits, Grav and collaborators simulate a synthetic population of NEOs all above 140 m in size. With these improved population models, they demonstrate that the common tactic of using an asteroids absolute magnitude as a

  4. The effects of the tensor coupling term in the Zimanyi-Moszkowski model for unpolarized nuclear matter

    International Nuclear Information System (INIS)

    Ru-Keng Su; Li Li; Hong-Qiu Song

    1998-01-01

    The effects of the tensor coupling term on nuclear matter in the Zimanyi-Moszkowki (ZM) model are investigated. It is shown that the tensor coupling term in the ZM model leaves the thermodynamical properties of nuclear matter almost unchanged. The corrections of tensor coupling to the critical point of the liquid-gas phase transition are given. (author)

  5. A relevancy algorithm for curating earth science data around phenomenon

    Science.gov (United States)

    Maskey, Manil; Ramachandran, Rahul; Li, Xiang; Weigel, Amanda; Bugbee, Kaylin; Gatlin, Patrick; Miller, J. J.

    2017-09-01

    Earth science data are being collected for various science needs and applications, processed using different algorithms at multiple resolutions and coverages, and then archived at different archiving centers for distribution and stewardship causing difficulty in data discovery. Curation, which typically occurs in museums, art galleries, and libraries, is traditionally defined as the process of collecting and organizing information around a common subject matter or a topic of interest. Curating data sets around topics or areas of interest addresses some of the data discovery needs in the field of Earth science, especially for unanticipated users of data. This paper describes a methodology to automate search and selection of data around specific phenomena. Different components of the methodology including the assumptions, the process, and the relevancy ranking algorithm are described. The paper makes two unique contributions to improving data search and discovery capabilities. First, the paper describes a novel methodology developed for automatically curating data around a topic using Earth science metadata records. Second, the methodology has been implemented as a stand-alone web service that is utilized to augment search and usability of data in a variety of tools.

  6. Techniques For Near-Earth Interplanetary Matter Detection And Characterisation From Optical Ground-Based Observatories

    Science.gov (United States)

    Ocaña, Francisco

    2017-05-01

    PhD Thesis defended the 5th June 2017. Universidad Complutense de Madrid.This dissertation undertakes the research of the interplanetary matter near the Earth using two different observational approaches.The first one is based on the detection of the sunlight reflected by the bodies. The detection and characterisation of these nearby population require networks of medium-sized telescopes to survey and track them. We design a robotic system (the TBT telescopes) for the European Space Agency as a prototype for a future network. The first unit is already installed in Spain and we present the results of the commissioning. Additionally we evaluate the expected performance of such an instrument using a simulation with a synthetic population. We consider that the system designed is a powerful instrument for nearby asteroid discovery and tracking. It is based on commercial components, and therefore ready for a scalable implementation in a global network.Meanwhile the bodies smaller than asteroids are observed using the atmosphere as a detector. When these particles collide with the atmospheric molecules they are heated, ablated, sublimated, and finally light is emitted by these hot vapours, what we call meteors. We conduct the investigation of these meteors to study the meteoroids. In particular we address two different topics: On one hand we explore the size/mass frequency distribution of meteoroids using flux determination when the collide into the atmosphere. We develop a method to determine this flux using video observations of meteors and analyse the properties of meteors as an optical proxy to meteoroids in order to maximise the detection. It yields three ground-based observational solutions that we transform into instrumental designs. First we design and develop a meteor all-sky detection station for Observatorio UCM and use the Draconids 2011 campaign as a showcase for the flux determination, with successful results. Then we investigate the observation of meteors

  7. Possible mechanism of the interplanetary medium effect on the diurnal rotation rate of the Earth

    International Nuclear Information System (INIS)

    Krymskij, P.F.

    1993-01-01

    Mechanism is proposed for effect of the solar wind and interplanetary magnetic field on the Earth rotation. In the mechanism base is Hall current generation in the plasma layer of the magnetosphere tail

  8. Effect of organic matter amendment, arsenic amendment and water management regime on rice grain arsenic species

    International Nuclear Information System (INIS)

    Norton, Gareth J.; Adomako, Eureka E.; Deacon, Claire M.; Carey, Anne-Marie; Price, Adam H.; Meharg, Andrew A.

    2013-01-01

    Arsenic accumulation in rice grain has been identified as a major problem in some regions of Asia. A study was conducted to investigate the effect of increased organic matter in the soil on the release of arsenic into soil pore water and accumulation of arsenic species within rice grain. It was observed that high concentrations of soil arsenic and organic matter caused a reduction in plant growth and delayed flowering time. Total grain arsenic accumulation was higher in the plants grown in high soil arsenic in combination with high organic matter, with an increase in the percentage of organic arsenic species observed. The results indicate that the application of organic matter should be done with caution in paddy soils which have high soil arsenic, as this may lead to an increase in accumulation of arsenic within rice grains. Results also confirm that flooding conditions substantially increase grain arsenic. -- Highlights: ► High soil arsenic and organic matter caused a reduction in plant growth. ► A delayed flowering time was observed in high arsenic and organic matter soil. ► Total grain arsenic increased in high arsenic and organic matter soil. ► Percentage organic arsenic in the grain altered in arsenic and organic matter soil. -- The addition of high amounts of organic matter to soils led to an increase in total rice grain arsenic, as well as alteration in the percentage arsenic species in the rice grains

  9. Decoherence as a way to measure extremely soft collisions with dark matter

    Science.gov (United States)

    Riedel, C. Jess; Yavin, Itay

    2017-07-01

    A new frontier in the search for dark matter (DM) is based on the idea of detecting the decoherence caused by DM scattering against a mesoscopic superposition of normal matter. Such superpositions are uniquely sensitive to very small momentum transfers from new particles and forces, especially DM with a mass below 100 MeV. Here we investigate what sorts of dark sectors are inaccessible with existing methods but would induce noticeable decoherence in the next generation of matter interferometers. We show that very soft but medium range (0.1 nm - 1 μ m ) elastic interactions between nuclei and DM are particularly suitable. We construct toy models for such interactions, discuss existing constraints, and delineate the expected sensitivity of forthcoming experiments. The first hints of DM in these devices would appear as small variations in the anomalous decoherence rate with a period of one sidereal day. This is a generic signature of interstellar sources of decoherence, clearly distinguishing it from terrestrial backgrounds. The OTIMA experiment under development in Vienna will begin to probe Earth-thermalizing DM once sidereal variations in the background decoherence rate are pushed below one part in a hundred for superposed 5-nm gold nanoparticles. The proposals by Bateman et al. and Geraci et al. could be similarly sensitive although they would require at least a month of data taking. DM that is absorbed or elastically reflected by the Earth, and so avoids a greenhouse density enhancement, would not be detectable by those three experiments. On the other hand, the aggressive proposals of the MAQRO collaboration and Pino et al. would immediately open up many orders of magnitude in DM mass, interaction range, and coupling strength, regardless of how DM behaves in bulk matter.

  10. Effect of rare-earth-based nanoparticles on the erythrocyte osmotic adaptation

    OpenAIRE

    О. К. Пакулова; В. К. Kлочков; Н. С. Кавок; И. А. Костина; А. С. Сопотова; В. А. Бондаренко

    2017-01-01

    Rare-earth-based nanoparticles (REB NPs) have been employed in molecular and cell biology due to their unique features. However, their interaction with biosystems and the influence on cell functioning are poorly understood. In this study effect of REB NPs (composed of dielectric nanocrystalls of cerium dioxide and orthovanadates of gadolinium and yttrium) with different form-factor as well as REB NPs-cholesterol complexes on the adaptation of human erythrocytes to hypertonic lysis (4 M NaCl) ...

  11. Extrinsic CPT violation in neutrino oscillations in matter

    International Nuclear Information System (INIS)

    Jacobson, Magnus; Ohlsson, Tommy

    2004-01-01

    We investigate matter-induced (or extrinsic) CPT violation effects in neutrino oscillations in matter. Especially, we present approximate analytical formulas for the CPT-violating probability differences for three flavor neutrino oscillations in matter with an arbitrary matter density profile. Note that we assume that the CPT invariance theorem holds, which means that the CPT violation effects arise entirely because of the presence of matter. As special cases of matter density profiles, we consider constant and step-function matter density profiles, which are relevant for neutrino oscillation physics in accelerator and reactor long baseline experiments as well as neutrino factories. Finally, the implications of extrinsic CPT violation on neutrino oscillations in matter for several past, present, and future long baseline experiments are estimated

  12. Organic matter cycling in a neotropical reservoir: effects of temperature and experimental conditions

    Directory of Open Access Journals (Sweden)

    Flávia Bottino

    2013-06-01

    Full Text Available AIM:This study reports a comparison between decomposition kinetics of detritus derived from two macrophyte species (Polygonum lapathifolium L.: Polygonaceae; Eichhornia azurea (Sw. Kunth.: Pontederiaceae growing in a neotropical reservoir (Brazil, under laboratory and field conditions, in order to assess hypotheses on the main differences in factors affecting organic matter cycling, including the effect of temperature. METHODS: Plant and water samples were collected from the reservoir in August 2009. In field incubation mass loss was assessed using a litter bag technique and in the laboratory the decay was followed using a decomposition chamber maintained under controlled conditions (i.e. in the dark, at 15 ºC and 25 ºC. A kinetic model was adopted to explain and compare the organic matter decay, ANOVA (Repeated Measures testing was used to describe the differences between the treatments and a linear correlation was used to compare in situ and in vitro experiments. RESULTS: The mass decay was faster in natural conditions with rapid release of the labile-soluble portion. The simulated values of mineralization rates of dissolved organic matter and refractory organic matter were rapid in high temperatures (25 ºC. The high Q10 results (mainly for E. azurea, and experimental conditions, and outcomes of ANOVA testing indicate the temperature variation (10 ºC influence the rates of mass decay. CONCLUSIONS: The results suggested rapid organic matter cycling in warm months (from October to December supporting the microbial loop. Although the particulate organic matter losses are high in field conditions the results are of the same magnitude in both conditions suggesting an equivalence of the mass decay kinetic.

  13. Earthworm effects without earthworms: inoculation of raw organic matter with worm-worked substrates alters microbial community functioning.

    Science.gov (United States)

    Aira, Manuel; Domínguez, Jorge

    2011-01-27

    Earthworms are key organisms in organic matter decomposition because of the interactions they establish with soil microorganisms. They enhance decomposition rates through the joint action of direct effects (i.e. effects due to direct earthworm activity such as digestion, burrowing, etc) and indirect effects (i.e. effects derived from earthworm activities such as cast ageing). Here we test whether indirect earthworm effects affect microbial community functioning in the substrate, as when earthworms are present (i. e., direct effects). To address these questions we inoculated fresh organic matter (pig manure) with worm-worked substrates (vermicompost) produced by three different earthworm species. Two doses of each vermicompost were used (2.5 and 10%). We hypothesized that the presence of worm-worked material in the fresh organic matter will result in an inoculum of different microorganisms and nutrients. This inoculum should interact with microbial communities in fresh organic matter, thus promoting modifications similar to those found when earthworms are present. Inoculation of worm-worked substrates provoked significant increases in microbial biomass and enzyme activities (β-glucosidase, cellulase, phosphatase and protease). These indirect effects were similar to, although lower than, those obtained in pig manure with earthworms (direct and indirect earthworm effects). In general, the effects were not dose-dependent, suggesting the existence of a threshold at which they were triggered. Our data reveal that the relationships between earthworms and microorganisms are far from being understood, and suggest the existence of several positive feedbacks during earthworm activity as a result of the interactions between direct and indirect effects, since their combination produces stronger modifications to microbial biomass and enzyme activity.

  14. Earthworm effects without earthworms: inoculation of raw organic matter with worm-worked substrates alters microbial community functioning.

    Directory of Open Access Journals (Sweden)

    Manuel Aira

    Full Text Available BACKGROUND: Earthworms are key organisms in organic matter decomposition because of the interactions they establish with soil microorganisms. They enhance decomposition rates through the joint action of direct effects (i.e. effects due to direct earthworm activity such as digestion, burrowing, etc and indirect effects (i.e. effects derived from earthworm activities such as cast ageing. Here we test whether indirect earthworm effects affect microbial community functioning in the substrate, as when earthworms are present (i. e., direct effects. METHODOLOGY/PRINCIPAL FINDINGS: To address these questions we inoculated fresh organic matter (pig manure with worm-worked substrates (vermicompost produced by three different earthworm species. Two doses of each vermicompost were used (2.5 and 10%. We hypothesized that the presence of worm-worked material in the fresh organic matter will result in an inoculum of different microorganisms and nutrients. This inoculum should interact with microbial communities in fresh organic matter, thus promoting modifications similar to those found when earthworms are present. Inoculation of worm-worked substrates provoked significant increases in microbial biomass and enzyme activities (β-glucosidase, cellulase, phosphatase and protease. These indirect effects were similar to, although lower than, those obtained in pig manure with earthworms (direct and indirect earthworm effects. In general, the effects were not dose-dependent, suggesting the existence of a threshold at which they were triggered. CONCLUSION/SIGNIFICANCE: Our data reveal that the relationships between earthworms and microorganisms are far from being understood, and suggest the existence of several positive feedbacks during earthworm activity as a result of the interactions between direct and indirect effects, since their combination produces stronger modifications to microbial biomass and enzyme activity.

  15. Solar rotation effects on the thermospheres of Mars and Earth.

    Science.gov (United States)

    Forbes, Jeffrey M; Bruinsma, Sean; Lemoine, Frank G

    2006-06-02

    The responses of Earth's and Mars' thermospheres to the quasi-periodic (27-day) variation of solar flux due to solar rotation were measured contemporaneously, revealing that this response is twice as large for Earth as for Mars. Per typical 20-unit change in 10.7-centimeter radio flux (used as a proxy for extreme ultraviolet flux) reaching each planet, we found temperature changes of 42.0 +/- 8.0 kelvin and 19.2 +/- 3.6 kelvin for Earth and Mars, respectively. Existing data for Venus indicate values of 3.6 +/- 0.6 kelvin. Our observational result constrains comparative planetary thermosphere simulations and may help resolve existing uncertainties in thermal balance processes, particularly CO2 cooling.

  16. Propagation Velocity of Solid Earth Tides

    Science.gov (United States)

    Pathak, S.

    2017-12-01

    One of the significant considerations in most of the geodetic investigations is to take into account the outcome of Solid Earth tides on the location and its consequent impact on the time series of coordinates. In this research work, the propagation velocity resulting from the Solid Earth tides between the Indian stations is computed. Mean daily coordinates for the stations have been computed by applying static precise point positioning technique for a day. The computed coordinates are used as an input for computing the tidal displacements at the stations by Gravity method along three directions at 1-minute interval for 24 hours. Further the baseline distances are computed between four Indian stations. Computation of the propagation velocity for Solid Earth tides can be done by the virtue of study of the concurrent effect of it in-between the stations of identified baseline distance along with the time consumed by the tides for reaching from one station to another. The propagation velocity helps in distinguishing the impact at any station if the consequence at a known station for a specific time-period is known. Thus, with the knowledge of propagation velocity, the spatial and temporal effects of solid earth tides can be estimated with respect to a known station. As theoretically explained, the tides generated are due to the position of celestial bodies rotating about Earth. So the need of study is to observe the correlation of propagation velocity with the rotation speed of the Earth. The propagation velocity of Solid Earth tides comes out to be in the range of 440-470 m/s. This velocity comes out to be in a good agreement with the Earth's rotation speed.

  17. Towards a chiral effective field theory of nuclear matter

    International Nuclear Information System (INIS)

    Mallik, S.

    2008-01-01

    As a preliminary attempt to formulate an effective theory of nuclear matter, we undertake to calculate the effective pole parameters of nucleon in such a medium. We begin with the virial expansion of these parameters to leading order in nucleon number density in terms of the on-shell NN scattering amplitude. We then proceed to calculate the same parameters in the effective theory, getting a formula for the nucleon mass-shift to leading order, that was known already to give too large a value to be acceptable at normal nuclear density. At this point the virial expansion suggests a modification of this formula, which we carry out following Weinberg's method for the two-nucleon system in the effective theory. The results are encouraging enough to attempt a complete, next-to-leading order calculation of the off-shell nucleon spectral function in nuclear medium. (author)

  18. Gravitational effect of distant earth relief within the territory of former Czechoslovakia

    Czech Academy of Sciences Publication Activity Database

    Mikuška, J.; Pašteka, R.; Mrlina, Jan; Marušiak, J.

    2008-01-01

    Roč. 52, č. 3 (2008), s. 381-396 ISSN 0039-3169 R&D Projects: GA AV ČR IAA3012308 Grant - others:EC(XE) ENK6-CT2000-00056; APVV(SK) APVV-99-002905 Institutional research plan: CEZ:AV0Z30120515 Keywords : Bouguer gravity anomaly * distant topographic effect * distant bathymetric correction Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 0.770, year: 2008

  19. A Closer Earth and the Faint Young Sun Paradox: Modification of the Laws of Gravitation or Sun/Earth Mass Losses?

    Directory of Open Access Journals (Sweden)

    Lorenzo Iorio

    2013-10-01

    Full Text Available Given a solar luminosity LAr = 0.75L0 at the beginning of the Archean 3.8 Ga ago, where L0 is the present-day one, if the heliocentric distance, r, of the Earth was rAr = 0.956r0, the solar irradiance would have been as large as IAr = 0.82I0. It would have allowed for a liquid ocean on the terrestrial surface, which, otherwise, would have been frozen, contrary to the empirical evidence. By further assuming that some physical mechanism subsequently displaced the Earth towards its current distance in such a way that the irradiance stayed substantially constant over the entire Archean from 3.8 to 2.5 Ga ago, a relative recession per year as large as r˙/r ≈3.4 × 10−11 a−1 would have been required. Although such a figure is roughly of the same order of magnitude of the value of the Hubble parameter 3.8 Ga ago HAr = 1.192H0 = 8.2 × 10−11 a−1, standard general relativity rules out cosmological explanations for the hypothesized Earth’s recession rate. Instead, a class of modified theories of gravitation with nonminimal coupling between the matter and the metric naturally predicts a secular variation of the relative distance of a localized two-body system, thus yielding a potentially viable candidate to explain the putative recession of the Earth’s orbit. Another competing mechanism of classical origin that could, in principle, allow for the desired effect is the mass loss, which either the Sun or the Earth itself may have experienced during the Archean. On the one hand, this implies that our planet should have lost 2% of its present mass in the form of eroded/evaporated hydrosphere. On the other hand, it is widely believed that the Sun could have lost mass at an enhanced rate, due to a stronger solar wind in the past for not more than ≈ 0.2–0.3 Ga.

  20. A Novel Theory For The Origin And Evolution Of Stars And Planets, Including Earth, Which Asks, 'Was The Earth Once A Small Bright Star?'

    Science.gov (United States)

    Cimorelli, S. A.; Samuels, C.

    2001-12-01

    Improved prediction methods for earthquakes and volcanic activity will naturally follow from our theory, based on new concepts of the earth's interior composition, state and activity. In this paper we present a novel hypothesis for the formation and evolution of galaxies, stars (including black holes (BHs), neutron stars, giant, mid-size, dwarf, dying and dead stars), planets (including earth), and moons. Present day phenomenon will be used to substantiate the validity of this hypothesis. Every `body' is a multiple type of star, generated from modified pieces called particle proliferators, of a dislodged/expanded BH (of category 2 (c-2)) which explodes due to a collision with another expanded BH (or explodes on its own). This includes the sun, and the planet earth, which is a type of dead star. Such that, if we remove layers of the earth, starting with the crust, we will find evidence of each preceding star formation, from brown to blue, and the remains of the particle proliferator as the innermost core is reached. We show that the hypothesis is consistent with both the available astronomical data regarding stellar evolution and planetary formation; as well as the evolution of the earth itself, by considerations of the available geophysical data. Where data is not available, reasonably simple experiments are suggested to demonstrate further the consistency and viability of the hypothesis. Theories are presented to help define and explain phenomenon such as how two (or more) c-2 BHs expand and collide to form a small `big bang' (It is postulated that there was a small big bang to form each galaxy, similar to the big bang from a category 1 BH(s) that may have formed our universe. The Great Attractors would be massive c-2 BHs and act on galaxy clusters similar to the massive c-3 BHs at the center of Galaxies acting on stars.). This in turn afforded the material/matter to form all the galactic bodies, including the dark matter inside the galaxies that we catalogue as

  1. Implications of the DAMA and CRESST experiments for mirror matter-type dark matter

    International Nuclear Information System (INIS)

    Foot, R.

    2004-01-01

    Mirror atoms are expected to be a significant component of the galactic dark matter halo if mirror matter is identified with the nonbaryonic dark matter in the Universe. Mirror matter can interact with ordinary matter via gravity and via the photon-mirror photon kinetic mixing interaction--causing mirror charged particles to couple to ordinary photons with an effective electric charge εe. This means that the nuclei of mirror atoms can elastically scatter off the nuclei of ordinary atoms, leading to nuclear recoils, which can be detected in existing dark matter experiments. We show that the dark matter experiments most sensitive to this type of dark matter candidate (via the nuclear recoil signature) are the DAMA/NaI and CRESST/Sapphire experiments. Furthermore, we show that the impressive annual modulation signal obtained by the DAMA/NaI experiment can be explained by mirror matter-type dark matter for vertical bar ε vertical bar ∼5x10 -9 and is supported by DAMA's absolute rate measurement as well as the CRESST/Sapphire data. This value of vertical bar ε vertical bar is consistent with the value obtained from various solar system anomalies including the Pioneer spacecraft anomaly, anomalous meteorite events and lack of small craters on the asteroid Eros. It is also consistent with standard big bang nucleosynthesis

  2. Probes for dark matter physics

    Science.gov (United States)

    Khlopov, Maxim Yu.

    The existence of cosmological dark matter is in the bedrock of the modern cosmology. The dark matter is assumed to be nonbaryonic and consists of new stable particles. Weakly Interacting Massive Particle (WIMP) miracle appeals to search for neutral stable weakly interacting particles in underground experiments by their nuclear recoil and at colliders by missing energy and momentum, which they carry out. However, the lack of WIMP effects in their direct underground searches and at colliders can appeal to other forms of dark matter candidates. These candidates may be weakly interacting slim particles, superweakly interacting particles, or composite dark matter, in which new particles are bound. Their existence should lead to cosmological effects that can find probes in the astrophysical data. However, if composite dark matter contains stable electrically charged leptons and quarks bound by ordinary Coulomb interaction in elusive dark atoms, these charged constituents of dark atoms can be the subject of direct experimental test at the colliders. The models, predicting stable particles with charge ‑ 2 without stable particles with charges + 1 and ‑ 1 can avoid severe constraints on anomalous isotopes of light elements and provide solution for the puzzles of dark matter searches. In such models, the excessive ‑ 2 charged particles are bound with primordial helium in O-helium atoms, maintaining specific nuclear-interacting form of the dark matter. The successful development of composite dark matter scenarios appeals for experimental search for doubly charged constituents of dark atoms, making experimental search for exotic stable double charged particles experimentum crucis for dark atoms of composite dark matter.

  3. Collective effects in diffuse ambiplasma

    International Nuclear Information System (INIS)

    Rogers, S.H.

    1981-01-01

    All laboratory evidence to date indicates that particles materialize from energy only in matter-antimatter pairs and, conversely, disappear only when such pairs annihilate. This observed law suggests that early in the Big Bang, when material and radiation were in equilibrium, the universe contained equal amounts of matter and antimatter. Since the earth, the solar system, and the neighboring stars, as implied by cosmic ray data, appear to be exclusively matter, their antimatter counterparts should by all rights exist elsewhere. Astronomical observations, however, have revealed no signs of antimatter on a large scale; in particular, the energetic gamma rays that would originate in the boundaries between matter and antimatter are not observed. The dilemma is resolved if the laboratory law is violated even minutely, a possibility that is now being tested by experiment. On the other hand, the dilemma disappears if the matter and antimatter exist in separate regions without, in effect, interacting. In this case there must be a repulsive force between the matter and antimatter that prevents them from mixing; in particular, such a force is crucial to the coexistence of large, diffuse regions akin to the galactic interstellar clouds. Predictions of the outcome of matter-antimatter contact are usually based entirely on binary collisions. This disseration explores the possibility that collective effects dominate interactions between diffuse matter and antimatter and give rise to the necessary repulsive force. Some years ago, a mechanism was proposed in which a thin, magnetized layer of ambiplasma kept matter and antimatter plasmas separated with the energy released in occasional annihilation

  4. Nitrogen deficiency in maize. I. Effects on crop growth, development, dry matter partitioning, and kernel set

    International Nuclear Information System (INIS)

    Uhart, S.A.; Andrade, F.H.

    1995-01-01

    Variations in N availability affect growth and development of maize (Zea mays L.) and may lead to changes in crop physiological conditions at flowering and in kernel set. The objectives of this study were (i) to establish the effect of N availability on crop development, crop radiation interception, radiation use efficiency, and dry matter partitioning; and (ii) to study the relationship between kernel number and crop growth at flowering and between kernel number and crop N accumulation at flowering. Three experiments with a commercial hybrid (DK636) were carried out under field conditions at the INTA Balcarce Experimental Station, Argentina, without water limitations. The treatments consisted of different radiation levels, obtained by shading, combined with different levels of N availability obtained by the addition of N fertilizer or organic matter to immobilize N. Nitrogen deficiencies delayed both vegetative and reproductive phenological development, slightly reduced leaf emergence rate, and strongly diminished leaf expansion rate and leaf area duration. Nitrogen deficiencies reduced radiation interception as much as radiation use efficiency and their effects on the ear dry mater/total dry matter ratio at harvest were associated with crop growth rate reductions at flowering. Dry matter partitioning to reproductive sinks at flowering and the ear dry matter/total dry matter ratio at harvest were reduced by N shortages. Significant relationships between kernel number and N accumulation rate or crop growth rate at flowering were fitted by linear + plateau functions with thresholds above which kernel number and grain yield did not increase

  5. Effect of Oxygen Enrichment in Propane Laminar Diffusion Flames under Microgravity and Earth Gravity Conditions

    Science.gov (United States)

    Bhatia, Pramod; Singh, Ravinder

    2017-06-01

    Diffusion flames are the most common type of flame which we see in our daily life such as candle flame and match-stick flame. Also, they are the most used flames in practical combustion system such as industrial burner (coal fired, gas fired or oil fired), diesel engines, gas turbines, and solid fuel rockets. In the present study, steady-state global chemistry calculations for 24 different flames were performed using an axisymmetric computational fluid dynamics code (UNICORN). Computation involved simulations of inverse and normal diffusion flames of propane in earth and microgravity condition with varying oxidizer compositions (21, 30, 50, 100 % O2, by mole, in N2). 2 cases were compared with the experimental result for validating the computational model. These flames were stabilized on a 5.5 mm diameter burner with 10 mm of burner length. The effect of oxygen enrichment and variation in gravity (earth gravity and microgravity) on shape and size of diffusion flames, flame temperature, flame velocity have been studied from the computational result obtained. Oxygen enrichment resulted in significant increase in flame temperature for both types of diffusion flames. Also, oxygen enrichment and gravity variation have significant effect on the flame configuration of normal diffusion flames in comparison with inverse diffusion flames. Microgravity normal diffusion flames are spherical in shape and much wider in comparison to earth gravity normal diffusion flames. In inverse diffusion flames, microgravity flames were wider than earth gravity flames. However, microgravity inverse flames were not spherical in shape.

  6. Effect of Long-Period Ocean Tides on the Earth's Polar Motion

    Science.gov (United States)

    Gross, R. S.; Chao, B. F.; Desai, S. D.

    1997-01-01

    The second-degree zonal tide raising potential is symmetric about the polar axis and hence can excite the Earth's polar motion only through its action upon nonaxisymmetric features of the Earth such as the oceans.

  7. Solar and terrestrial physics. [effects of solar activities on earth environment

    Science.gov (United States)

    1975-01-01

    The effects of solar radiation on the near space and biomental earth, the upper atmosphere, and the magnetosphere are discussed. Data obtained from the OSO satellites pertaining to the solar cycle variation of extreme ultraviolet (EUV) radiation are analyzed. The effects of solar cycle variation of the characteristics of the solar wind are examined. The fluid mechanics of shock waves and the specific relationship to the characteristics of solar shock waves are investigated. The solar and corpuscular heating of the upper atmosphere is reported based on the findings of the AEROS and NATE experiments. Seasonal variations of the upper atmosphere composition are plotted based on OGO-6 mass spectrometer data.

  8. The filtering effect of buildings on airborne particulate matter

    International Nuclear Information System (INIS)

    Christensen, G.C.; Mustonen, R.

    1987-06-01

    Within the radioecological programme of the Nordic Liaison Committee for Atomic Energy (NKA), the possible consequences of a major reactor accident are one of its main research branches. This study of the filtering effect of buildings on airborne particulate matter has been one part of this branch. The absorbed dose to a person from a passing radioactive cloud will be lower if he has been indoors and not ourdoors during the cloud passage. The aim of this study has been to find filtering factors for typical Finnish and Norwegian houses to use in model work

  9. Dynamics of the Sun-Earth-Moon System

    Indian Academy of Sciences (India)

    The dynamics of the Sun-Earth-Moon system is discussed with special attention to the effects of. Sun's perturbations on the Moon's orbit around the Earth. Important secular effects are the re- gression of the nodes, the advance of the perigee and the increase in the Moon's mean longitude. We discuss the relationship of the ...

  10. Baryon destruction by asymmetric dark matter

    International Nuclear Information System (INIS)

    Davoudiasl, Hooman; Morrissey, David E.; Tulin, Sean; Sigurdson, Kris

    2011-01-01

    We investigate new and unusual signals that arise in theories where dark matter is asymmetric and carries a net antibaryon number, as may occur when the dark matter abundance is linked to the baryon abundance. Antibaryonic dark matter can cause induced nucleon decay by annihilating visible baryons through inelastic scattering. These processes lead to an effective nucleon lifetime of 10 29 -10 32 yrs in terrestrial nucleon decay experiments, if baryon number transfer between visible and dark sectors arises through new physics at the weak scale. The possibility of induced nucleon decay motivates a novel approach for direct detection of cosmic dark matter in nucleon decay experiments. Monojet searches (and related signatures) at hadron colliders also provide a complementary probe of weak-scale dark-matter-induced baryon number violation. Finally, we discuss the effects of baryon-destroying dark matter on stellar systems and show that it can be consistent with existing observations.

  11. Rare earth metals, rare earth hydrides, and rare earth oxides as thin films

    International Nuclear Information System (INIS)

    Gasgnier, M.

    1980-01-01

    The review deals with pure rare earth materials such as rare earth metals, rare earth hydrides, and rare earth oxides as thin films. Several preparation techniques, control methods, and nature of possible contaminations of thin films are described. These films can now be produced in an extremely well-known state concerning chemical composition, structure and texture. Structural, electric, magnetic, and optical properties of thin films are studied and discussed in comparison with the bulk state. The greatest contamination of metallic rare earth thin films is caused by reaction with hydrogen or with water vapour. The compound with an f.c.c. structure is the dihydride LnH 2 (Ln = lanthanides). The oxygen contamination takes place after annealing at higher temperatures. Then there appears a compound with a b.c.c. structure which is the C-type sesquioxide C-Ln 2 O 3 . At room atmosphere dihydride light rare earth thin films are converted to hydroxide Ln(OH) 3 . For heavy rare earth thin films the oxinitride LnNsub(x)Osub(y) is observed. The LnO-type compound was never seen. The present review tries to set the stage anew for the investigations to be undertaken in the future especially through the new generations of electron microscopes

  12. The zonal tidal effect on the variation in the rotation rate of the Earth with a fluid core I. Improvements on the theoretical formulae

    Science.gov (United States)

    Zhang, Han-Wei; Zheng, Yong; Du, Lan; Pan, Guan-Song

    The tidal variation in Earth's rotation rate is a periodical response to solar-lunar tide generating potential (TGP). In this article, the factor of the fluid core, which is related with the variation in the polar moment of inertia of the Earth, is considered and introduced distinctly into the theoretical formula of the variation in the Earth's rotational rate caused by lunar-solar tide-producing force based on the dynamics principle of the fluid core Earth. Different from previously work, some Doodson developments are given including the variation formulae of the Earth's rotational rate, LOD and UT1. The reasons are pointed why the moment of inertia for the scale should be the effective polar rotational moment of inertia of the mantle and the Love number should be the effective Love number of the mantle. It is also indicated that the factor of the fluid core is consistent with the effect of the effective Love number of the mantle due to fluid core.

  13. Greenhouse Earth: A Traveling Exhibition

    International Nuclear Information System (INIS)

    Booth, W.H.; Caesar, S.

    1992-09-01

    The Franklin Institute Science Museum provided an exhibit entitled the Greenhouse Earth: A Traveling Exhibition. This 3500 square-foot exhibit on global climate change was developed in collaboration with the Association of Science-Technology Centers. The exhibit opened at The Franklin Institute on February 14, 1992, welcoming 291,000 visitors over its three-month stay. During its three-year tour, Greenhouse Earth will travel to ten US cities, reaching two million visitors. Greenhouse Earth aims to deepen public understanding of the scientific issues of global warming and the conservation measures that can be taken to slow its effects. The exhibit features hands-on exhibitry, interactive computer programs and videos, a theater production, a ''demonstration cart,'' guided tours, and lectures. supplemental educational programs at the Institute included a teachers preview, a symposium on climate change, and a ''satellite field trip.'' The development of Greenhouse Earth included front-end and formative evaluation procedures. Evaluation includes interviews with visitors, prototypes, and summative surveys for participating museums. During its stay in Philadelphia, Greenhouse Earth was covered by the local and national press, with reviews in print and broadcast media. Greenhouse Earth is the first large-scale museum exhibit to address global climate change

  14. Safety culture as a matter of regulatory control and regulatory effectiveness

    International Nuclear Information System (INIS)

    Camargo, C.T.M.; Furieri, E.B.; Arrieta, L.A.I.; Almeida, C.U.C.

    2002-01-01

    More than 15 years have passed since the term 'safety culture' was introduced by the International Nuclear Safety Advisory Group (INSAG), and although the concept now is widely accepted, practical applications and characteristics have been disseminated mainly for nuclear power plant operating organizations. There is still a lack of international guidance on the use of safety culture as a regulatory matter and on the application of the concept within regulatory organizations. This work explores the meaning of safety culture in two different fields: as an element of safety management systems it shall be a matter of regulatory control; as a complementary tool for quality management it should be used to enhance regulatory effectiveness. Brazilian recent experience on regulating nuclear power reactors provide some examples on how the concept of safety culture may influence regulatory strategies and regulatory management. (author)

  15. Effect of mosaic virus diseases on dry matter content and starch ...

    African Journals Online (AJOL)

    The effect of mosaic virus diseases on dry matter content and starch yield of five local accessions of cassava, “Ankrah”, “AW/17, “Tomfa”, “Dagarti” and “Tuaka” was evaluated. Tomfa showed the highest (95%) incidence of the disease, index of severity of symptoms for all plants (ISSAP) of 3.70, as well as, for diseased plants ...

  16. Lepton Flavorful Fifth Force and Depth-Dependent Neutrino Matter Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Wise, Mark B. [Caltech; Zhang, Yue [Northwestern U.

    2018-03-01

    We consider a fifth force to be an interaction that couples to matter with a strength that grows with the number of atoms. In addition to competing with the strength of gravity a fifth force can give rise to violations of the equivalence principle. Current long range constraints on the strength and range of fifth forces are very impressive. Amongst possible fifth forces are those that couple to lepton flavorful charges $L_e-L_{\\mu}$ or $L_e-L_{\\tau}$. They have the property that their range and strength are also constrained by neutrino interactions with matter. In this brief note we review the existing constraints on the allowed parameter space in gauged $U(1)_{L_e-L_{\\mu}, L_{\\tau}}$. We find two regions where neutrino oscillation experiments are at the frontier of probing such a new force. In particular, there is an allowed range of parameter space where neutrino matter interactions relevant for long baseline oscillation experiments depend on the depth of the neutrino beam below the surface of the earth.

  17. Orbital and Landing Operations at Near-Earth

    Science.gov (United States)

    Scheeres, D. J.

    1995-01-01

    Orbital and landing operations about near-Earth asteroids are different than classical orbital operations about large bodies. The major differences lie with the small mass of the asteroid, the lower orbital velocities, the larger Solar tide and radiation pressure perturbations, the irregular shape of the asteroid and the potential for non-uniform rotation of the asteroid. These differences change the nature of orbits about an asteroid to where it is often common to find trajectories that evolve from stable, near-circular orbits to crashing or escaping orbits in a matter of days. The understanding and control of such orbits is important if a human or robotic presence at asteroids is to be commonplace in the future.

  18. Diatomaceous earth and oil enhance effectiveness of Metarhizium anisopliae against Triatoma infestans.

    Science.gov (United States)

    Luz, Christian; Rodrigues, Juscelino; Rocha, Luiz F N

    2012-04-01

    Entomopathogenic fungi, especially Metarhizium anisopliae, have potential for integrated control of peridomestic triatomine bugs. However, the high susceptibility of these vectors to fungal infection at elevated ambient humidities decreases in the comparatively dry conditions that often prevail in their microhabitats. A formulation adapted to this target pest that induces high and quick mortality can help to overcome these drawbacks. In the present study diatomaceous earth, which is used against pests of stored grains or as an additive to mycoinsecticides, delayed but did not reduce in vitro germination of M. anisopliae s.l. IP 46 conidia after >24h agitation without affecting viability, and did not hamper the survival of Triatoma infestans nymphs exposed to treated surfaces. The settling behavior of nymphs on a treated surface in choice tests depended on the concentration of diatomaceous earth and ambient light level. Conidia formulated with diatomaceous earth and a vegetable oil synergized the insecticidal effect of the fungus in nymphs, and quickly killed all treated insects, even at 75% relative humidity (LT(90) 8.3 days) where unformulated conidia caused only 25% mortality after a 25 days exposure. The improved performance of a combined oil and desiccant dust formulation of this Metarhizium isolate raises the likelihood for its successful mycoinsecticidal use for triatomine control and, apparently, against other domestic insect pests. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Effect of rare earth filtration on patient exposure, dose reduction, and image quality in oral panoramic radiology

    International Nuclear Information System (INIS)

    Tyndall, D.A.; Washburn, D.B.

    1987-01-01

    Rare earth intensifying screen material (Gd2O2S:Tb) was added to the standard Al filtration of an oral panoramic x-ray unit, resulting in a beam capable of achieving reductions in patient dose without a loss of image quality. The added rare earth filtration technique resulted in patient dose reductions of 21-56%, depending on anatomic sites, when compared to the conventional Al filtration technique. Films generated from both techniques were measured densitometrically and evaluated by a panel of practicing clinicians. Diagnostically significant differences were minimal. The results indicate that use of rare earth filters in oral panoramic radiography is an effective means of reducing exposures of dental patients to ionizing radiation

  20. Resource Handbook--Space Beyond the Earth. A Supplement to Basic Curriculum Guide--Science, Grades K-6.

    Science.gov (United States)

    Starr, John W., 3rd., Ed.

    GRADES OR AGES: Grades K-6. SUBJECT MATTER: Science; space. ORGANIZATION AND PHYSICAL APPEARANCE: The guide is divided into four units: 1) the sun, earth, and moon; 2) stars and planets; 3) exploring space; 4) man's existence in space. Each unit includes initiatory and developmental activities. There are also sections on evaluation, vocabulary,…

  1. Rare earth elements in suspended and bottom sediments of the Mandovi estuary,central west coast of India: Influence of mining

    Digital Repository Service at National Institute of Oceanography (India)

    Shynu, R.; Rao, V.P.; Kessarkar, P.M.; Rao, T.G.

    Rare earth elements (REEs) in the suspended particulate matter (SPM) of the Mandovi estuary indicated that the mean total-REEs and light REE to heavy REE ratios are lower than that of the average suspended sediment in World Rivers and Post...

  2. Cs adsorption on the clay-sized fraction of various soils: effect of organic matter destruction and charge compensating cation

    International Nuclear Information System (INIS)

    Staunton, S.; Levacic, P.

    1999-01-01

    The association of organic matter with clay minerals may decrease their affinity for Cs and thus enhance its bioavailability. We have investigated this hypothesis by comparing Cs adsorption on several soils, both topsoils and the corresponding subsoils, before and after organic matter destruction with H 2 O 2 . The clay-sized fractions were homoionic in either K, Na or Ca, to avoid artefacts due to variable composition of the exchange complex. All experiments were carried out in dilute suspension under controlled conditions. The affinity of the clay-sized fractions for Cs and the value of the Freundlich b parameter are typical of illites. This supports the hypothesis that the adsorption properties of soils are dominated by small amounts of illite. However, if this is the case, the affinity of soil illites is higher than that of reference illites. The destruction of organic matter has a variable effect. In some cases, a marked enhancement is observed, in others there is no significant effect, or a small decrease. There is no clear pattern relating the effect of organic matter destruction and either dominant clay mineralogy or organic matter content. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  3. Dark matter, neutron stars, and strange quark matter.

    Science.gov (United States)

    Perez-Garcia, M Angeles; Silk, Joseph; Stone, Jirina R

    2010-10-01

    We show that self-annihilating weakly interacting massive particle (WIMP) dark matter accreted onto neutron stars may provide a mechanism to seed compact objects with long-lived lumps of strange quark matter, or strangelets, for WIMP masses above a few GeV. This effect may trigger a conversion of most of the star into a strange star. We use an energy estimate for the long-lived strangelet based on the Fermi-gas model combined with the MIT bag model to set a new limit on the possible values of the WIMP mass that can be especially relevant for subdominant species of massive neutralinos.

  4. Studying the Physical Basis of Global Warming: Thermal Effects of the Interaction between Radiation and Matter and Greenhouse Effect

    Science.gov (United States)

    Besson, Ugo; De Ambrosis, Anna; Mascheretti, Paolo

    2010-01-01

    We present a teaching module dealing with the thermal effects of interaction between radiation and matter, the infrared emission of bodies and the greenhouse effect devoted to university level and teacher education. The module stresses the dependence of the optical properties of materials (transparency, absorptivity and emissivity) on radiation…

  5. Halo-independent methods for inelastic dark matter scattering

    International Nuclear Information System (INIS)

    Bozorgnia, Nassim; Schwetz, Thomas; Herrero-Garcia, Juan; Zupan, Jure

    2013-01-01

    We present halo-independent methods to analyze the results of dark matter direct detection experiments assuming inelastic scattering. We focus on the annual modulation signal reported by DAMA/LIBRA and present three different halo-independent tests. First, we compare it to the upper limit on the unmodulated rate from XENON100 using (a) the trivial requirement that the amplitude of the annual modulation has to be smaller than the bound on the unmodulated rate, and (b) a bound on the annual modulation amplitude based on an expansion in the Earth's velocity. The third test uses the special predictions of the signal shape for inelastic scattering and allows for an internal consistency check of the data without referring to any astrophysics. We conclude that a strong conflict between DAMA/LIBRA and XENON100 in the framework of spin-independent inelastic scattering can be established independently of the local properties of the dark matter halo

  6. Effects of energy conservation on equilibrium properties of hot asymmetric nuclear matter

    Science.gov (United States)

    Zhang, Zhen; Ko, Che Ming

    2018-01-01

    Based on the relativistic Vlasov-Uehling-Uhlenbeck transport model, which includes relativistic scalar and vector potentials on baryons, we consider an N -Δ -π system in a box with periodic boundary conditions to study the effects of energy conservation in particle production and absorption processes on the equilibrium properties of the system. The density and temperature of the matter in the box are taken to be similar to the hot dense matter formed in heavy ion collisions at intermediate energies. We find that to maintain the equilibrium numbers of N ,Δ , and π , which depend on the mean-field potentials of N and Δ , we must include these potentials in the energy conservation condition that determines the momenta of outgoing particles after a scattering or decay process. We further find that the baryon scalar potentials mainly affect the Δ and pion equilibrium numbers, while the baryon vector potentials have considerable effect on the effective charged pion ratio at equilibrium. Our results thus indicate that it is essential to include in the transport model the effect of potentials in the energy conservation of a scattering or decay process, which is ignored in most transport models, for studying pion production in heavy ion collisions.

  7. On the Effects of the Evolution of Microbial Mats and Land Plants on the Earth as a Planet. Photometric and Spectroscopic Light Curves of Paleo-Earths

    Science.gov (United States)

    Sanromá, E.; Pallé, E.; García Munõz, A.

    2013-04-01

    Understanding the spectral and photometric variability of the Earth and the rest of the solar system planets has become of utmost importance for the future characterization of rocky exoplanets. As this is not only interesting at present times but also along the planetary evolution, we studied the effect that the evolution of microbial mats and plants over land has had on the way our planet looks from afar. As life evolved, continental surfaces changed gradually and non-uniformly from deserts through microbial mats to land plants, modifying the reflective properties of the ground and most likely the distribution of moisture and cloudiness. Here, we used a radiative transfer model of the Earth, together with geological paleo-records of the continental distribution and a reconstructed cloud distribution, to simulate the visible and near-IR radiation reflected by our planet as a function of Earth's rotation. We found that the evolution from deserts to microbial mats and to land plants produces detectable changes in the globally averaged Earth's reflectance. The variability of each surface type is located in different bands and can induce reflectance changes of up to 40% in period of hours. We conclude that by using photometric observations of an Earth-like planet at different photometric bands it would be possible to discriminate between different surface types. While recent literature proposes the red-edge feature of vegetation near 0.7 μm as a signature for land plants, observations in near-IR bands can be equally or even better suited for this purpose.

  8. ON THE EFFECTS OF THE EVOLUTION OF MICROBIAL MATS AND LAND PLANTS ON THE EARTH AS A PLANET. PHOTOMETRIC AND SPECTROSCOPIC LIGHT CURVES OF PALEO-EARTHS

    International Nuclear Information System (INIS)

    Sanromá, E.; Pallé, E.; García Munõz, A.

    2013-01-01

    Understanding the spectral and photometric variability of the Earth and the rest of the solar system planets has become of utmost importance for the future characterization of rocky exoplanets. As this is not only interesting at present times but also along the planetary evolution, we studied the effect that the evolution of microbial mats and plants over land has had on the way our planet looks from afar. As life evolved, continental surfaces changed gradually and non-uniformly from deserts through microbial mats to land plants, modifying the reflective properties of the ground and most likely the distribution of moisture and cloudiness. Here, we used a radiative transfer model of the Earth, together with geological paleo-records of the continental distribution and a reconstructed cloud distribution, to simulate the visible and near-IR radiation reflected by our planet as a function of Earth's rotation. We found that the evolution from deserts to microbial mats and to land plants produces detectable changes in the globally averaged Earth's reflectance. The variability of each surface type is located in different bands and can induce reflectance changes of up to 40% in period of hours. We conclude that by using photometric observations of an Earth-like planet at different photometric bands it would be possible to discriminate between different surface types. While recent literature proposes the red-edge feature of vegetation near 0.7 μm as a signature for land plants, observations in near-IR bands can be equally or even better suited for this purpose.

  9. MEST- avoid next extinction by a space-time effect

    Science.gov (United States)

    Cao, Dayong

    2013-03-01

    Sun's companion-dark hole seasonal took its dark comets belt and much dark matter to impact near our earth. And some of them probability hit on our earth. So this model kept and triggered periodic mass extinctions on our earth every 25 to 27 million years. After every impaction, many dark comets with very special tilted orbits were arrested and lurked in solar system. When the dark hole-Tyche goes near the solar system again, they will impact near planets. The Tyche, dark comet and Oort Cloud have their space-time center. Because the space-time are frequency and amplitude square of wave. Because the wave (space-time) can make a field, and gas has more wave and fluctuate. So they like dense gas ball and a dark dense field. They can absorb the space-time and wave. So they are ``dark'' like the dark matter which can break genetic codes of our lives by a dark space-time effect. So the upcoming next impaction will cause current ``biodiversity loss.'' The dark matter can change dead plants and animals to coal, oil and natural gas which are used as energy, but break our living environment. According to our experiments, which consciousness can use thought waves remotely to change their systemic model between Electron Clouds and electron holes of P-N Junction and can change output voltages of solar cells by a life information technology and a space-time effect, we hope to find a new method to the orbit of the Tyche to avoid next extinction. (see Dayong Cao, BAPS.2011.APR.K1.17 and BAPS.2012.MAR.P33.14) Support by AEEA

  10. Interaction of ionising radiations with matter

    International Nuclear Information System (INIS)

    Caudrelier, Olivier

    2010-01-01

    In a first part, this academic course addresses the interaction of non-charged particles with matter. The author more particularly addresses the interaction of a photon plasma with matter (attenuation of electromagnetic radiations, law of exponential attenuation, attenuation half value layer), the elementary phenomena of the interaction of a photon with matter (photoelectric effect, Compton effect, Thomson-Rayleigh scattering, materialisation, photo-nuclear reaction, prevalence domains, application in medical imagery), and the interaction of fast and slow neutrons with matter (elastic and inelastic scattering, radiative and non-radiative capture). The second part addresses the interaction of charged particles with matter. The author more particularly addresses the interaction with electrons present in the medium (ionization, excitation, stop efficiency, linear energy transfer, ionization linear density), the interaction with the nucleus (Bremsstrahlung), and the case of light particles (electrons) and of heavy particles (protons, alpha, fission products)

  11. Temperature modifies the health effects of particulate matter in Brisbane, Australia

    Science.gov (United States)

    Ren, Cizao; Tong, Shilu

    2006-11-01

    A few epidemiological studies have examined whether there was an interactive effect between temperature and ambient particulate matter on cardiorespiratory morbidity and mortality, but the results were inconsistent. The present study used three time-series approaches to explore whether maximum temperature modified the impact of ambient particulate matter less than 10 μm in diameter (PM10) on daily respiratory hospital admissions, cardiovascular hospital admissions, respiratory emergency visits, cardiovascular emergency visits, non-external cause mortality and cardiovascular mortality in Brisbane between 1996 and 2001. The analytical approaches included a bivariate response surface model, a non-stratification parametric model and a stratification parametric model. Results show that there existed a statistically significant interaction between PM10 and temperature on most health outcomes at various lags. PM10 exhibited more adverse health effects on warm days than cold days. The choice of the degree of freedom for smoothers to adjust for confounders and the selection of arbitrary cut-offs for temperature affected the interaction estimates to a certain extent, but did not change the overall conclusion. The results imply that it is important to control and reduce the emission of air particles in Brisbane, particularly when temperature increases.

  12. Naturalness in an Effective Field Theory for Neutron Star Matter

    International Nuclear Information System (INIS)

    Razeira, Moises; Vasconcellos, Cesar A.Z.; Bodmann, Bardo E.J.; Coelho, Helio T.; Dillig, Manfred

    2004-01-01

    High density hadronic matter is studied in a generalized relativistic multi-baryon lagrangian density. By comparing the predictions of our model with estimates obtained within a phenomenological naive dimensional analysis based on the naturalness of the coefficients of the theory, we show that naturalness plays a major role in effective field theory and, in combination with experiment, could represent a relevant criterium to select a model among others in the description of global static properties of neutron stars

  13. Study on speciation of rare earth elements in soil

    International Nuclear Information System (INIS)

    Wang Yuqi; Sun Jingxin; Chen Hongmin; Guo Fanqing; Wang Lijun; Zhang Shen

    1996-01-01

    The contents of rare earth elements (REE) in red soil, yellow brown soil and leached chernozem are studied. After extracted sequentially, REE in these soils are fractionated into seven forms, i.e., (I) water soluble, (II) exchangeable, (III) loosely bound to organic mater, (IV) bound to carbonate and specifically absorbed, (V) bound to Fe-Mn oxides, (VI) tightly bound to organic matter and (VII) residual forms. The contents of REE in every form are determined by NAA (neutron activation analysis). The results show that REE in soils mainly exist in residual form and REE in soluble forms are very limited (<7%)

  14. Tidal effects on Earth, Planets, Sun by far visiting moons

    Science.gov (United States)

    Fargion, Daniele

    2016-07-01

    The Earth has been formed by a huge mini-planet collision forming our Earth surface and our Moon today. Such a central collision hit was statistically rare. A much probable skimming or nearby encounter by other moons or planets had to occur. Indeed Recent observations suggest that many planetary-mass objects may be present in the outer solar system between the Kuiper belt and the Oort cloud. Gravitational perturbations may occasionally bring them into the inner solar system. Their passage near Earth could have generated gigantic tidal waves, large volcanic eruptions, sea regressions, large meteoritic impacts and drastic changes in global climate. They could have caused the major biological mass extinctions in the past in the geological records. For instance a ten times a terrestrial radius nearby impact scattering by a peripherical encounter by a small moon-like object will force huge tidal waves (hundred meter height), able to lead to huge tsunami and Earth-quake. Moreover the historical cumulative planet hits in larger and wider planets as Juppiter, Saturn, Uranus will leave a trace, as observed, in their tilted spin axis. Finally a large fraction of counter rotating moons in our solar system probe and test such a visiting mini-planet captur origination. In addition the Earth day duration variability in the early past did show a rare discountinuity, very probably indebt to such a visiting planet crossing event. These far planets in rare trajectory to our Sun may, in thousands event capture, also explain sudden historical and recent temperature changes.

  15. Effects of the interaction between dark energy and dark matter on cosmological parameters

    International Nuclear Information System (INIS)

    He, Jian-Hua; Wang, Bin

    2008-01-01

    We examine the effects of possible phenomenological interactions between dark energy and dark matter on cosmological parameters and their efficiency in solving the coincidence problem. We work with two simple parameterizations of the dynamical dark energy equation of state and the constant dark energy equation of state. Using observational data coming from the new 182 Gold type Ia supernova samples, the shift parameter of the Cosmic Microwave Background given by the three-year Wilkinson Microwave Anisotropy Probe observations and the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey, we perform a statistical joint analysis of different forms of phenomenological interaction between dark energy and dark matter

  16. Relationship between Particulate matter less than 10 microns exposures and health effects on humans in Ahvaz, Iran

    Directory of Open Access Journals (Sweden)

    Sahar Geravandi

    2015-06-01

    Full Text Available Background & Aims of the Study: Particulate matters less than 10 microns can absorb into your lungs and reacting with the moisture and enter the circulatory system directly through the airways. The aim of this study is to assess Behavior PM 10 data in different seasons and Determination effects on human health in Ahvaz city during 2013. Materials & Methods: Data Particulate matters less than 10 microns were taken from Ahvaz Department of Environment and Meteorological Organization. Sampling was performed for 24 hours in 4 stations. Method of sampling and analysis were performed according to EPA guideline. Processing data include the instruction set correction of averaging, coding and filtering. Finally, health-effects of Particulate matters less than 10 exposures were calculated with impact of meteorological parameters and converted as input file to the Air Q model. Results: PM 10 concentration in winter season was maximum amount in the year 2013. According to the research findings, highest and the lowest Particulate matters less than 10 microns concentrations during 2013 had the Bureau of Meteorology “Havashenasi” and Head office of ADoE “Mohitzist”. Sum of total numbers of cardiovascular death and hospitals admission to respiratory diseases attributed to Particulate matters less than 10 microns were 923 and 2342 cases in 2013. Conclusions: Particulate matter emissions are highly regulated in most industrialized countries. Due to environmental concerns, most industries and dust storm phenomena are required to decrease in source produce particle mater and kind of dust collection system to control particulate emissions. Pollution prevention and control measures that reduce Particulate matters less than 10 microns can very useful for expected to reduce people’s exposures to Sulfur dioxide.

  17. Effects of long-term exposure to particulate matter and metal components on mortality in the Rome longitudinal study

    NARCIS (Netherlands)

    Badaloni, Chiara; Cesaroni, Giulia; Cerza, Francesco; Davoli, Marina; Brunekreef, Bert; Forastiere, Francesco

    2017-01-01

    BACKGROUND: The effect of long-term exposure to metal components in particulate matter on mortality are still controversial. OBJECTIVES: To study the association between long-term exposure to PM10, PM2.5, PM2.5 absorbance, particulate matter components (copper, iron, zinc, sulfur, silicon,

  18. An accurate analytic description of neutrino oscillations in matter

    Science.gov (United States)

    Akhmedov, E. Kh.; Niro, Viviana

    2008-12-01

    A simple closed-form analytic expression for the probability of two-flavour neutrino oscillations in a matter with an arbitrary density profile is derived. Our formula is based on a perturbative expansion and allows an easy calculation of higher order corrections. The expansion parameter is small when the density changes relatively slowly along the neutrino path and/or neutrino energy is not very close to the Mikheyev-Smirnov-Wolfenstein (MSW) resonance energy. Our approximation is not equivalent to the adiabatic approximation and actually goes beyond it. We demonstrate the validity of our results using a few model density profiles, including the PREM density profile of the Earth. It is shown that by combining the results obtained from the expansions valid below and above the MSW resonance one can obtain a very good description of neutrino oscillations in matter in the entire energy range, including the resonance region.

  19. Rare earth metals for automotive exhaust catalysts

    International Nuclear Information System (INIS)

    Shinjoh, Hirohumi

    2006-01-01

    The usage of rare earth metals for automotive exhaust catalysts is demonstrated in this paper. Rare earth metals have been widely used in automotive catalysts. In particular, three-way catalysts require the use of ceria compounds as oxygen storage materials, and lanthana as both a stabilizer of alumina and a promoter. The application for diesel catalysts is also illustrated. Effects of inclusion of rare earth metals in automotive catalysts are discussed

  20. Dynamic Effects of the Earth's Rotation Caused by the Annual and Semi-Annual Cyclic Mass Redistribution of the Planet

    Directory of Open Access Journals (Sweden)

    M. Yu. Barkin

    2016-01-01

    Full Text Available The paper deals with development of the theory of perturbed rotational motion of a celestial body with variable geometry of the masses. Its main task is to study the impact of annual and semi-annual variations of the Earth's mass geometry (a component of its inertia tensor, as well as a component of its relative angular momentum, on the movement of the Earth's poles and its axial rotation. The body is considered to be a free (isolated, and the problem formulation corresponds to the classical Liouville problem on rotation of a variable body. Euler conical movement of the axially symmetric body with an arbitrary constant half-angle  is assumed as the unperturbed motion. In the classical theory of the Earth's rotation this angle is usually assumed to be zero.In the last 20 years, accuracy to determine the Earth rotation parameters owing to using methods of space geodesy and method of Very Long Baseline Interferometry (VLBI has increased by about three orders of magnitude and has made about  i.e., in angle measure it is about 10 - 20 arc-microseconds. According to experts, the theory of the Earth's rotation with such precision is not created yet. The paper is focused just on the new dynamic studies of the Earth rotation at a higher level of accuracy than has been done in previous studies, using a new approach to the problem, based on the new forms of the equations of motion (in the Andoyer variables and the analytical methods of perturbation theory (small parameter method.The problem of perturbed rotational motion with variable geometry and variable mass relative angular momentum in the first approximation is solved in Andoyer variables and projections of the angular velocity of the planet rotation. The analytical solution allows us to run applications to study dynamic effects from above factors for various bodies in the solar system, including the Earth. The solution allowed us to obtain the following parameters of the fundamental effects in the