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Sample records for kamland provide strong

  1. Kamland Results

    CERN Document Server

    Inoue, K

    2003-01-01

    The LMA solution of the solar neutrino problem has been explored with the 1,000 ton liquid scinatillator detector, KamLAND. It utilizes nuclear power reactors distributing effectively 180km from the experimental site. Comparing observed neutrino rate with the calculation of reactor operation histories, an evidence for reactor neutrino disapearance has been obtained from 162 ton-year exposure data. This deficit is only compatible with the LMA solution and the other solutions in the two neutrino oscillation hypotheisis are excluded at 99.95% confidence level.

  2. The Solar Neutrino Problem after the first results from Kamland

    CERN Document Server

    Bandyopadhyay, A; Gandhi, R; Goswami, S; Roy, D P; Bandyopadhyay, Abhijit; Choubey, Sandhya; Gandhi, Raj; Goswami, Srubabati

    2003-01-01

    The first results from the KamLAND experiment have provided confirmational evidence for the Large Mixing Angle (LMA) MSW solution to the solar neutrino problem. We do a global analysis of solar and the recently announced KamLAND data (both rate and spectrum) and investigate its effect on the allowed region in the $\\Delta m^2-\\tan^2\\theta$ plane. The best-fit from a combined analysis which uses the KamLAND rate plus global solar data comes at $\\Delta m^2 = 6.06 \\times 10^{-5}$ eV $^2$ and $\\tan^2\\theta=0.42$, very close to the global solar best-fit, leaving a large allowed region within the global solar LMA contour. The inclusion of the KamLAND spectral data in the global fit gives a best-fit $\\Delta m^2 = 7.15 \\times 10^{-5}$ eV $^2$ and $\\tan^2\\theta=0.42$ and constrains the allowed areas within LMA, leaving essentially two allowed zones. Maximal mixing though allowed by the KamLAND data alone is disfavored by the global solar data and remains disallowed at about $3\\sigma$. The LOW solution is now ruled out ...

  3. Reactor on-off antineutrino measurement with KamLAND

    NARCIS (Netherlands)

    Gando, A.; Gando, Y.; Hanakago, H.; Ikeda, H.; Inoue, K.; Ishidoshiro, K.; Ishikawa, H.; Koga, M.; Matsuda, R.; Matsuda, S.; Mitsui, T.; Motoki, D.; Nakamura, K.; Obata, A.; Oki, A.; Oki, Y.; Otani, M.; Shimizu, I.; Shirai, J.; Suzuki, A.; Takemoto, Y.; Tamae, K.; Ueshima, K.; Watanabe, A.; Xu, B.D.; Yamada, S.; Yamauchi, Y.; Yoshida, H.; Kozlov, A.; Yoshida, S.; Piepke, A.; Banks, T.I.; Fujikawa, B.K.; Han, K.; O'Donnell, T.; Berger, B.E.; Learned, J.G.; Matsuno, S.; Sakai, M.; Efremenko, Y.; Karwowski, H.J.; Markoff, D.M.; Tornow, W.; Detwiler, J.A.; Enomoto, S.; Decowski, M.P.

    2013-01-01

    The recent long-term shutdown of Japanese nuclear reactors has resulted in a significantly reduced reactor ν¯e flux at KamLAND. This running condition provides a unique opportunity to confirm and constrain backgrounds for the reactor ν¯e oscillation analysis. The data set also has improved sensitivi

  4. The Status of KamLAND After Purification

    Science.gov (United States)

    Grant, Christopher

    2010-02-01

    KamLAND is a 1-kton liquid scintillation detector located in the Kamioka underground laboratory, in Japan. KamLAND has provided a precision measurement of δm^221 using reactor anti-neutrinos, and yielded first observational evidence of geologically produced anti-neutrinos. Since April of 2007, the collaboration has been working on the purification of the detector with the goal of observing 862 keV, ^7Be solar neutrinos. Two purification campaigns have concluded, with a total of 5.4 ktons of scintillator circulated through a distillation and nitrogen purge system. The results of purification and the overall background reduction factors will be presented, along with an update of the ^7Be solar neutrino analysis. )

  5. Testing the solar LMA region with KamLAND data

    CERN Document Server

    Bandyopadhyay, A; Gandhi, R; Goswami, S; Roy, D P; Bandyopadhyay, Abhijit; Choubey, Sandhya; Gandhi, Raj; Goswami, Srubabati

    2003-01-01

    In this paper we investigate the potential of 1 and 3 kiloTon-years(kTy) of KamLAND data to further constrain the $\\Delta m^2$ and $\\tan^2\\theta$ values allowed by the post-SNO NC global solar data. We find that although an energy integrated oscillation to no oscillation event-rate ratio in the range $\\sim$ 0.3-0.8 observed in KamLAND can provide support for the Large-Mixing Angle (LMA) solution, sensitive determination of the oscillation parameters will have to wait until the spectrum data is made available. We study the extent, dependence and characteristics of this sensitivity in and around the LMA region. Our analysis with 3 kTy simulated spectra shows that KamLAND spectrum data by itself can constrain $\\Delta m^2$ with a high precision if the simulation point lies around the LMA best-fit from global solar analysis. For spectra generated at lower values of $\\tan^2\\theta$ or higher values of $\\Delta m^2$, multiple regions become allowed indicating a significantly reduced reconstruction efficiency if the tr...

  6. The solar neutrino problem after the first results from KamLAND

    Energy Technology Data Exchange (ETDEWEB)

    Bandyopadhyay, Abhijit; Choubey, Sandhya; Gandhi, Raj; Goswami, Srubabati; Roy, D.P

    2003-05-01

    The first results from the KamLAND experiment have provided confirmational evidence for the Large Mixing Angle (LMA) Mikheyev-Smirnov-Wolfenstein (MSW) solution to the solar neutrino problem. We do a global analysis of solar and the recently announced KamLAND data (both rate and spectrum) and investigate its effect on the allowed region in the {delta}m{sup 2}-tan{sup 2}{theta} plane. The best-fit from a combined analysis which uses the KamLAND rate plus global solar data comes at {delta}m{sup 2}=6.06x10{sup -5} eV{sup 2} and tan{sup 2}{theta}=0.42, very close to the global solar best-fit, leaving a large allowed region within the global solar LMA contour. The inclusion of the KamLAND spectral data in the global fit gives a best-fit {delta}m{sup 2}=7.17x10{sup -5} eV{sup 2} and tan{sup 2}{theta}=0.43 and constrains the allowed areas within LMA, leaving essentially two allowed zones. Maximal mixing though allowed by the KamLAND data alone is disfavored by the global solar data and remains disallowed at about 3{sigma}. The low {delta}m{sup 2} solution (LOW) is now ruled out at about 5{sigma} with respect to the LMA solution.

  7. Low Background Phase of KamLAND

    Science.gov (United States)

    Keefer, Gregory

    2008-04-01

    The KamLAND collaboration operates a 1 kton liquid scintillation detector in the Kamioka mine in Japan. KamLAND's main scientific results are the precision measurement of the solar δm^2 utilizing reactor anti-neutrinos and first evidence for the observation of geologically produced anti-neutrinos. The KamLAND collaboration has been working toward upgrading the detector for a low background phase. During the spring of 2007, we performed the first phase of purification by circulating 1.3 ktons of KamLAND liquid scintillator through a newly developed distillation and purging system. The ultimate goal of purification is to allow for a direct measurement of the 862 keV, ^7Be neutrinos originating from the Sun. A description of the purification process, liquid scintillator quality control measures, and detector monitoring will be presented. The achieved background reduction after this first phase of purification and planned future work on KamLAND will be discussed.

  8. KamLAND Results and Future

    Science.gov (United States)

    Mitsui, Tadao; KamLAND Collaboration

    2011-12-01

    KamLAND results, current status, and near-future plans are reviewed. For reactor and geoneutrino physics, reduction of the systematic uncertainties is underway, while taking subsequent data. For the detection of 7Be solar neutrinos, purification of the scintillator by distillation will start soon.

  9. Reactor On-Off Antineutrino Measurement with KamLAND

    CERN Document Server

    ,

    2013-01-01

    The recent long-term shutdown of Japanese nuclear reactors has resulted in a significantly reduced reactor $\\bar{nu}_{e}$ flux at KamLAND. This running condition provides a unique opportunity to confirm and constrain backgrounds for the reactor $\\bar{nu}_{e}$ oscillation analysis. The data set also has improved sensitivity for other $\\bar{nu}_{e}$ signals, in particular $\\bar{nu}_{e}$'s produced in $\\beta$-decays from $^{238}$U and $^{232}$Th within the Earth's interior, whose energy spectrum overlaps with that of reactor $\\bar{nu}_{e}$'s. Including constraints on $\\theta_{13}$ from accelerator and short-baseline reactor neutrino experiments, a combined three-flavor analysis of solar and KamLAND data gives fit values for the oscillation parameters of $tan^{2} \\theta_{12} = 0.436^{+0.029}_{-0.025}$, $\\Delta m^{2}_{21} = 7.53^{+0.18}_{-0.18} \\times 10^{-5} {eV}^{2}$, and $sin^{2} \\theta_{13} = 0.023^{+0.002}_{-0.002}$. Assuming a chondritic Th/U mass ratio, we obtain $116^{+28}_{-27}$ $\\bar{nu}_{e}$ events from...

  10. KamLAND's precision neutrino oscillation measurements

    Science.gov (United States)

    Decowski, M. P.

    2016-07-01

    The KamLAND experiment started operation in the Spring of 2002 and is operational to this day. The experiment observes signals from electron antineutrinos from distant nuclear reactors. The program, spanning more than a decade, allowed the determination of LMA-MSW as the solution to the solar neutrino transformation results (under the assumption of CPT invariance) and the measurement of various neutrino oscillation parameters. In particular, the solar mass-splitting Δ m212 was determined to high precision. Besides the study of neutrino oscillation, KamLAND started the investigation of geologically produced antineutrinos (geo-ν‾e). The collaboration also reported on a variety of other topics related to particle and astroparticle physics.

  11. Solar Neutrino Oscillation Parameters after KamLAND

    CERN Document Server

    Goswami, S; Choubey, S; Goswami, Srubabati; Bandyopadhyay, Abhijit; Choubey, Sandhya

    2003-01-01

    We explore the impact of the data from the KamLAND experiment in constraining neutrino mass and mixing angles involved in solar neutrino oscillations. In particular we discuss the precision with which we can determine the the mass squared difference $\\Delta m^2_{solar}$ and the mixing angle $\\theta_{solar}$ from combined solar and KamLAND data. We show that the precision with which $\\Delta m^_{solar}$ can be determined improves drastically with the KamLAND data but the sensitivity of KamLAND to the mixing angle is not as good. We study the effect of enhanced statistics in KamLAND as well as reduced systematics in improving the precision. We also show the effect of the SNO salt data in improving the precision. Finally we discuss how a dedicated reactor experiment with a baseline of 70 km can improve the $\\theta_{solar}$ sensitivity by a large amount.

  12. KamLAND Sensitivity to Neutrinos from Pre-Supernova Stars

    CERN Document Server

    Asakura, K; Gando, Y; Hachiya, T; Hayashida, S; Ikeda, H; Inoue, K; Ishidoshiro, K; Ishikawa, T; Ishio, S; Koga, M; Matsuda, S; Mitsui, T; Motoki, D; Nakamura, K; Obara, S; Oura, T; Shimizu, I; Shirahata, Y; Shirai, J; Suzuki, A; Tachibana, H; Tamae, K; Ueshima, K; Watanabe, H; Xu, B D; Kozlov, A; Takemoto, Y; Yoshida, S; Fushimi, K; Piepke, A; Banks, T I; Berger, B E; Fujikawa, B K; O'Donnell, T; Learned, J G; Maricic, J; Matsuno, S; Sakai, M; Winslow, L A; Efremenko, Y; Karwowski, H J; Markoff, D M; Tornow, W; Detwiler, J A; Enomoto, S; Decowski, M P

    2015-01-01

    In the late stages of nuclear burning for massive stars ($M$> 10 $M_{sun}$), the production of neutrino-antineutrino pairs through various processes becomes the dominant mechanism of stellar cooling. As the star evolves, the energy of these neutrinos increases and in the days preceding the supernova a significant fraction of emitted electron anti-neutrinos exceeds the threshold for inverse beta decay on free hydrogen. This is the golden channel for liquid scintillator detectors because the coincidence signature allows for significant reductions in background signals. We find that the kiloton-scale liquid scintillator detector KamLAND can detect these pre-supernova neutrinos from a star with a mass of 25 $M_{sun}$ at a distance less than 660 pc with 3{\\sigma} significance before the supernova. This limit is dependent on the neutrino mass hierarchy and background levels. KamLAND takes data continuously and can provide an alarm for supernovae to the community.

  13. KamLAND results and the radiogenic terrestrial heat

    CERN Document Server

    Fiorentini, G; Mantovani, F; Ricci, B; Fiorentini, Gianni; Lissia, Marcello; Mantovani, Fabio; Ricci, Barbara

    2005-01-01

    We find that recent results from the KamLAND collaboration on geologically produced antineutrinos, N(U+Th) = 28+16-15 events, correspond to a radiogenic heat production from Uranium and Thorium decay chains H(U+Th) = 38+35-33 TW. The 99% confidence limit on the geo-neutrino signal translates into the upper bound H(U+Th) < 162 TW, which is much weaker than that claimed by KamLAND, H(U+Th) < 60 TW, based on a too narrow class of geological models. We also performed an analysis of KamLAND data including recent high precision measurements of the C13(\\alpha,n)O16 cross section. The result, N(U+Th) = 31+14-13, corroborates the evidence (approx 2.5\\sigma) for geo-neutrinos in KamLAND data.

  14. Neutrino Oscillation Parameters After High Statistics KamLAND Results

    CERN Document Server

    Bandyopadhyay, Abhijit; Goswami, Srubabati; Petcov, S T; Roy, D P

    2008-01-01

    We do a re-analysis to asses the impact of the results of the Borexino experiment and the recent 2.8 KTy KamLAND data on the solar neutrino oscillation parameters. The current Borexino results are found to have no impact on the allowed solar neutrino parameter space. The new KamLAND data causes a significant reduction of the allowed range of $\\Delta m^2_{21}$, determining it with an unprecedented precision of 8.3% at 3$\\sigma$. The precision of $\\Delta m^2_{21}$ is controlled practically by the KamLAND data alone. Inclusion of new KamLAND results also improves the upper bound on $\\sin^2\\theta_{12}$, but the precision of this parameter continues to be controlled by the solar data. The third mixing angle is constrained to be $\\sin^2\\theta_{13} < 0.063$ at $3\\sigma$ from a combined fit to the solar, KamLAND, atmospheric and CHOOZ results. We also address the issue of how much further reduction of allowed range of $\\Delta m^2_{21}$ and $\\sin^2\\theta_{12}$ is possible with increased statistics from KamLAND. We ...

  15. Phylogenomics provides strong evidence for relationships of butterflies and moths

    Science.gov (United States)

    Kawahara, Akito Y.; Breinholt, Jesse W.

    2014-01-01

    Butterflies and moths constitute some of the most popular and charismatic insects. Lepidoptera include approximately 160 000 described species, many of which are important model organisms. Previous studies on the evolution of Lepidoptera did not confidently place butterflies, and many relationships among superfamilies in the megadiverse clade Ditrysia remain largely uncertain. We generated a molecular dataset with 46 taxa, combining 33 new transcriptomes with 13 available genomes, transcriptomes and expressed sequence tags (ESTs). Using HaMStR with a Lepidoptera-specific core-orthologue set of single copy loci, we identified 2696 genes for inclusion into the phylogenomic analysis. Nucleotides and amino acids of the all-gene, all-taxon dataset yielded nearly identical, well-supported trees. Monophyly of butterflies (Papilionoidea) was strongly supported, and the group included skippers (Hesperiidae) and the enigmatic butterfly–moths (Hedylidae). Butterflies were placed sister to the remaining obtectomeran Lepidoptera, and the latter was grouped with greater than or equal to 87% bootstrap support. Establishing confident relationships among the four most diverse macroheteroceran superfamilies was previously challenging, but we recovered 100% bootstrap support for the following relationships: ((Geometroidea, Noctuoidea), (Bombycoidea, Lasiocampoidea)). We present the first robust, transcriptome-based tree of Lepidoptera that strongly contradicts historical placement of butterflies, and provide an evolutionary framework for genomic, developmental and ecological studies on this diverse insect order. PMID:24966318

  16. Phylogenomics provides strong evidence for relationships of butterflies and moths.

    Science.gov (United States)

    Kawahara, Akito Y; Breinholt, Jesse W

    2014-08-07

    Butterflies and moths constitute some of the most popular and charismatic insects. Lepidoptera include approximately 160 000 described species, many of which are important model organisms. Previous studies on the evolution of Lepidoptera did not confidently place butterflies, and many relationships among superfamilies in the megadiverse clade Ditrysia remain largely uncertain. We generated a molecular dataset with 46 taxa, combining 33 new transcriptomes with 13 available genomes, transcriptomes and expressed sequence tags (ESTs). Using HaMStR with a Lepidoptera-specific core-orthologue set of single copy loci, we identified 2696 genes for inclusion into the phylogenomic analysis. Nucleotides and amino acids of the all-gene, all-taxon dataset yielded nearly identical, well-supported trees. Monophyly of butterflies (Papilionoidea) was strongly supported, and the group included skippers (Hesperiidae) and the enigmatic butterfly-moths (Hedylidae). Butterflies were placed sister to the remaining obtectomeran Lepidoptera, and the latter was grouped with greater than or equal to 87% bootstrap support. Establishing confident relationships among the four most diverse macroheteroceran superfamilies was previously challenging, but we recovered 100% bootstrap support for the following relationships: ((Geometroidea, Noctuoidea), (Bombycoidea, Lasiocampoidea)). We present the first robust, transcriptome-based tree of Lepidoptera that strongly contradicts historical placement of butterflies, and provide an evolutionary framework for genomic, developmental and ecological studies on this diverse insect order. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  17. First observation of beryllium-7 solar neutrinos with KamLAND

    Science.gov (United States)

    Keefer, Gregory J.

    2009-09-01

    The international KamLAND collaboration operates a 1 kton liquid scintillation detector in the Kamioka mine in Gifu, Japan. KamLAND's main scientific results are the precision measurement of the solar Dm 2 12 = 7.58[Special characters omitted.] (stat) [Special characters omitted.] (syst) and tan 2 [straight theta] 12 = 0.56[Special characters omitted.] (stat) [Special characters omitted.] (syst) utilizing reactor n e and first evidence for the observation of geologically produced anti-neutrinos. In an effort to extend KamLAND's scientific reach, extensive research has been performed on preparing a spectroscopic measurement of 7 Be solar n e s. This work provides the first inclusive analysis of KamLAND's backgrounds below 1 MeV. 85 Kr and 210 Pb, dissolved in KamLAND liquid scintillator, were found to be the dominant source of low energy backgrounds. The concentration of these ultra-trace contaminants were determined to be 10 -20 g/g. This is more than 6 orders of magnitude lower than commercially available ultra-pure liquids. To attain a signal-to-background ratio suitable for the detection of 7 Be solar n e s, the concentration of these contaminants had to be reduced by 5 orders of magnitude. A comprehensive study of 210 Pb removal was undertaken over the course of this thesis. This work further covers techniques for the removal of 220 Rn, 222 Rn and their daughter nuclei from liquid scintillator at concentrations of 10^-18 g/g. Purification techniques studied in this work include water extraction, isotope exchange, adsorption, and distillation. These laboratory studies guided the design and implementation of a large scale purification system in the Kamioka mine. The purification system's design and operation is discussed in detail as well as specific experiments devised to control scintillator quality and radio-purity. The purification system's effectiveness in removing radioactive trace impurities is analyzed in detail. The total scintillator purified over two

  18. Providing Climate Policy Makers With a Strong Scientific Base (Invited)

    Science.gov (United States)

    Struzik, E.

    2009-12-01

    Scientists can and should inform public policy decisions in the Arctic. But the pace of climate change in the polar world has been occurring far more quickly than most scientists have been able to predict. This creates problems for decision-makers who recognize that difficult management decisions have to be made in matters pertaining to wildlife management, cultural integrity and economic development. With sea ice melting, glaciers receding, permafrost thawing, forest fires intensifying, and disease and invasive species rapidly moving north, the challenge for scientists to provide climate policy makers with a strong scientific base has been daunting. Clashing as this data sometimes does with the “traditional knowledge” of indigenous peoples in the north, it can also become very political. As a result the need to effectively communicate complex data is more imperative now than ever before. Here, the author describes how the work of scientists can often be misinterpreted or exploited in ways that were not intended. Examples include the inappropriate use of scientific data in decision-making on polar bears, caribou and other wildlife populations; the use of scientific data to debunk the fact that greenhouse gases are driving climate change, and the use of scientific data to position one scientist against another when there is no inherent conflict. This work will highlight the need for climate policy makers to increase support for scientists working in the Arctic, as well as illustrate why it is important to find new and more effective ways of communicating scientific data. Strategies that might be considered by granting agencies, scientists and climate policy decision-makers will also be discussed.

  19. KamLAND, solar antineutrinos and the solar magnetic field

    CERN Document Server

    Chauhan, B C; Torrente-Lujan, E; Chauhan, Bhag C.; Pulido, Joao

    2003-01-01

    In this work the possibility of detecting solar electron antineutrinos produced by a solar core magnetic field from the KamLAND recent observations is investigated. We find a scaling of the antineutrino probability with respect to the magnetic field profile in the sense that the same probability function can be reproduced by any profile with a suitable peak field value. In this way the solar electron antineutrino spectrum can be unambiguosly predicted. We use this scaling and the negative results indicated by the KamLAND experiment to obtain upper bounds on the solar electron antineutrino flux. We get $\\phi_{\\bar\

  20. Analysis of Future KamLAND and Gadolinium Doped SK

    Energy Technology Data Exchange (ETDEWEB)

    Choubey, Sandhya [INFN and SISSA, Trieste (Italy)

    2005-12-15

    We probe in detail the precision expected in the measurement of {delta}m{sub 21}{sup 2} and sin{sup 2}{theta}{sub 12} in the SNO, KamLAND, the proposed SK-Gd and a reactor experiment tuned to the SPMIN.

  1. Neutrino geophysics with KamLAND and future prospects

    CERN Document Server

    Enomoto, S; Inoue, K; Suzuki, A

    2005-01-01

    The Kamioka liquid scintillator anti-neutrino detector (KamLAND) is a low-energy and low-background neutrino detector which could be a useful probe for determining the U and Th abundances of the Earth. We constructed a model of the Earth in order to evaluate the rate of geologically produced anti-neutrinos (geo-neutrinos) detectable by KamLAND. We found that KamLAND can be used to determine the absolute abundances of U and Th in the Earth with an accuracy sufficient for placing important constraints on Earth's accretional process and succeeding thermal history. The present observation of geo-neutrinos with KamLAND is consistent with our model prediction based on the bulk silicate Earth (BSE) composition within the uncertainty of the measurement. If a neutrino detector were to be built in Hawaii, where effects of the continental crust would be negligible, it could be used to estimate the U and Th content in the lower mantle and the core. Our calculation of the geo-neutrino event rate on the Earth's surface ind...

  2. Setting Limits On The Power Of A Geo-reactor With Kamland Detector

    CERN Document Server

    Maricic, J

    2005-01-01

    The Earth's magnetic field has existed for at least 3 billion years with high and on average stable intensity, though with many fluctuations and reversals. One of the models, albeit rather controversial, proposed as the energy source of the Earth's magnetic field is a natural nuclear reactor inside the Earth's core [1] and [2]. This author maintains that this is the only model that generates sufficient power to energize the geo-magnetic field for 3 billion years. Even more, the reactor's ability to produce variable power levels including stops and restarts in its operations, provides a viable explanation, according to [2], for the random reversals of the geo-magnetic field that have been recorded numerous times during the Earth's history. In this study, Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) is used to set limits on the power of the putative geo-reactor. KamLAND is designed to detect anti-neutrinos from reactors around Japan, and thus can make a direct measurement of the anti-neutrino ra...

  3. Study of the Production of Radioactive Isotopes through Cosmic Muon Spallation in KamLAND

    Energy Technology Data Exchange (ETDEWEB)

    KamLAND Collaboration; Abe, S.; Enomoto, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, K.; Nakamura, M.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takemoto, Y.; Tamae, K.; Terashima, A.; Watanabe, H.; Yonezawa, E.; Yoshida, S.; Kozlov, A.; Murayama, H.; Busenitz, J.; Classen, T.; Grant, C.; Keefer, G.; Leonard, D. S.; McKee, D.; Piepke, A.; Banks, T. I.; Bloxham, T.; Detwiler, J. A.; Freedman, S. J.; Fujikawa, B. K.; Gray, F.; Guardincerri, E.; Hsu, L.; Ichimura, K.; Kadel, R.; Lendvai, C.; Luk, K.-B.; O' Donnell, T.; Steiner, H. M.; Winslow, L. A.; Dwyer, D. A.; Jillings, C.; Mauger, C.; McKeown, R. D.; Vogel, P.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Pakvasa, S.; Foster, J.; Horton-Smith, G. A.; Tang, A.; Dazeley, S.; Downum, K. E.; Gratta, G.; Tolich, K.; Bugg, W.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Heeger, K. M.; Piquemal, F.; Ricol, J.-S.; Decowski, M. P.

    2009-06-30

    Radioactive isotopes produced through cosmic muon spallation are a background for rare event detection in {nu} detectors, double-beta-decay experiments, and dark-matter searches. Understanding the nature of cosmogenic backgrounds is particularly important for future experiments aiming to determine the pep and CNO solar neutrino fluxes, for which the background is dominated by the spallation production of {sup 11}C. Data from the Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) provides valuable information for better understanding these backgrounds, especially in liquid scintillator, and for checking estimates from current simulations based upon MUSIC, FLUKA, and Geant4. Using the time correlation between detected muons and neutron captures, the neutron production yield in the KamLAND liquid scintillator is measured to be (2.8 {+-} 0.3) x 10{sup -4} n/({mu} {center_dot} (g/cm{sup 2})). For other isotopes, the production yield is determined from the observed time correlation related to known isotope lifetimes. We find some yields are inconsistent with extrapolations based on an accelerator muon beam experiment.

  4. KamLAND SENSITIVITY TO NEUTRINOS FROM PRE-SUPERNOVA STARS

    Energy Technology Data Exchange (ETDEWEB)

    Asakura, K.; Gando, A.; Gando, Y.; Hachiya, T.; Hayashida, S.; Ikeda, H.; Inoue, K.; Ishidoshiro, K.; Ishikawa, T.; Ishio, S.; Koga, M.; Matsuda, S.; Mitsui, T.; Motoki, D.; Nakamura, K.; Obara, S.; Oura, T.; Shimizu, I.; Shirahata, Y.; Shirai, J. [Research Center for Neutrino Science, Tohoku University, Sendai 980-8578 (Japan); Collaboration: KamLAND Collaboration; and others

    2016-02-10

    In the late stages of nuclear burning for massive stars (M > 8 M{sub ⊙}), the production of neutrino–antineutrino pairs through various processes becomes the dominant stellar cooling mechanism. As the star evolves, the energy of these neutrinos increases and in the days preceding the supernova a significant fraction of emitted electron anti-neutrinos exceeds the energy threshold for inverse beta decay on free hydrogen. This is the golden channel for liquid scintillator detectors because the coincidence signature allows for significant reductions in background signals. We find that the kiloton-scale liquid scintillator detector KamLAND can detect these pre-supernova neutrinos from a star with a mass of 25 M{sub ⊙} at a distance less than 690 pc with 3σ significance before the supernova. This limit is dependent on the neutrino mass ordering and background levels. KamLAND takes data continuously and can provide a supernova alert to the community.

  5. A Monte Carlo approach to Beryllium-7 solar neutrino analysis with KamLAND

    Science.gov (United States)

    Grant, Christopher Peter

    Terrestrial measurements of neutrinos produced by the Sun have been of great interest for over half a century because of their ability to test the accuracy of solar models. The first solar neutrinos detected with KamLAND provided a measurement of the 8B solar neutrino interaction rate above an analysis threshold of 5.5 MeV. This work describes efforts to extend KamLAND's detection sensitivity to solar neutrinos below 1 MeV, more specifically, those produced with an energy of 0.862 MeV from the 7Be electron-capture decay. Many of the difficulties in measuring solar neutrinos below 1 MeV arise from backgrounds caused abundantly by both naturally occurring, and man-made, radioactive nuclides. The primary nuclides of concern were 210Bi, 85Kr, and 39Ar. Since May of 2007, the KamLAND experiment has undergone two separate purification campaigns. During both campaigns a total of 5.4 ktons (about 6440 m3) of scintillator was circulated through a purification system, which utilized fractional distillation and nitrogen purging. After the purification campaign, reduction factors of 1.5 x 103 for 210Bi and 6.5 x 10 4 for 85Kr were observed. The reduction of the backgrounds provided a unique opportunity to observe the 7Be solar neutrino rate in KamLAND. An observation required detailed knowledge of the detector response at low energies, and to accomplish this, a full detector Monte Carlo simulation, called KLG4sim, was utilized. The optical model of the simulation was tuned to match the detector response observed in data after purification, and the software was optimized for the simulation of internal backgrounds used in the 7Be solar neutrino analysis. The results of this tuning and estimates from simulations of the internal backgrounds and external backgrounds caused by radioactivity on the detector components are presented. The first KamLAND analysis based on Monte Carlo simulations in the energy region below 2 MeV is shown here. The comparison of the chi2 between the null

  6. 7Be Solar Neutrino Measurement with KamLAND

    CERN Document Server

    Gando, A; Hanakago, H; Ikeda, H; Inoue, K; Ishidoshiro, K; Ishikawa, H; Kishimoto, Y; Koga, M; Matsuda, R; Matsuda, S; Mitsui, T; Motoki, D; Nakajima, K; Nakamura, K; Obata, A; Oki, A; Oki, Y; Otani, M; Shimizu, I; Shirai, J; Suzuki, A; Tamae, K; Ueshima, K; Watanabe, H; Xu, B D; Yamada, S; Yamauchi, Y; Yoshida, H; Kozlov, A; Takemoto, Y; Yoshida, S; Grant, C; Keefer, G; McKee, D W; Piepke, A; Banks, T I; Bloxham, T; Freedman, S J; Fujikawa, B K; Han, K; Hsu, L; Ichimura, K; Murayama, H; O'Donnell, T; Steiner, H M; Winslow, L A; Dwyer, D; Mauger, C; McKeown, R D; Zhang, C; Berger, B E; Lane, C E; Maricic, J; Miletic, T; Learned, J G; Sakai, M; Horton-Smith, G A; Tang, A; Downum, K E; Tolich, K; Efremenko, Y; Kamyshkov, Y; Perevozchikov, O; Karwowski, H J; Markoff, D M; Tornow, W; Detwiler, J A; Enomoto, S; Heeger, K; Decowski, M P

    2014-01-01

    We report a measurement of the neutrino-electron elastic scattering rate of 862 keV 7Be solar neutrinos based on a 165.4 kton-day exposure of KamLAND. The observed rate is 582 +/- 90 (kton-day)^-1, which corresponds to a 862 keV 7Be solar neutrino flux of (3.26 +/- 0.50) x 10^9 cm^-2s^-1, assuming a pure electron flavor flux. Comparing this flux with the standard solar model prediction and further assuming three flavor mixing, a nu_e survival probability of 0.66 +/- 0.14 is determined from the KamLAND data. Utilizing a global three flavor oscillation analysis, we obtain a total 7Be solar neutrino flux of (5.82 +/- 0.98) x 10^9 cm^-2s^-1, which is consistent with the standard solar model predictions.

  7. The KamLAND Full-Volume Calibration System

    Energy Technology Data Exchange (ETDEWEB)

    KamLAND Collaboration; Berger, B. E.; Busenitz, J.; Classen, T.; Decowski, M. P.; Dwyer, D. A.; Elor, G.; Frank, A.; Freedman, S. J.; Fujikawa, B. K.; Galloway, M.; Gray, F.; Heeger, K. M.; Hsu, L.; Ichimura, K.; Kadel, R.; Keefer, G.; Lendvai, C.; McKee, D.; O' Donnell, T.; Piepke, A.; Steiner, H. M.; Syversrud, D.; Wallig, J.; Winslow, L. A.; Ebihara, T.; Enomoto, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, K.; Owada, K.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Tamae, K.; Yoshida, S.; Kozlov, A.; Murayama, H.; Grant, C.; Leonard, D. S.; Luk, K.-B.; Jillings, C.; Mauger, C.; McKeown, R. D.; Zhang, C.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Pakvasa, S.; Foster, J.; Horton-Smith, G. A.; Tang, A.; Dazeley, S.; Downum, K. E.; Gratta, G.; Tolich, K.; Bugg, W.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Piquemal, F.; Ricol, J.-S.

    2009-03-05

    We have successfully built and operated a source deployment system for the KamLAND detector. This system was used to position radioactive sources throughout the delicate 1-kton liquid scintillator volume, while meeting stringent material cleanliness, material compatibility, and safety requirements. The calibration data obtained with this device were used to fully characterize detector position and energy reconstruction biases. As a result, the uncertainty in the size of the detector fiducial volume was reduced by a factor of two. Prior to calibration with this system, the fiducial volume was the largest source of systematic uncertainty in measuring the number of antineutrinos detected by KamLAND. This paper describes the design, operation and performance of this unique calibration system.

  8. 7Be solar neutrino measurement with KamLAND

    NARCIS (Netherlands)

    Gando, A.; et al., [Unknown; Decowski, M.P.

    2015-01-01

    We report a measurement of the neutrino-electron elastic scattering rate of 862 keV Be7 solar neutrinos based on a 165.4 kt d exposure of KamLAND. The observed rate is 582±94(kt d)−1, which corresponds to an 862-keV Be7 solar neutrino flux of (3.26±0.52)×109cm−2s−1, assuming a pure electron-flavor f

  9. Testing the solar LMA region with KamLAND data

    Energy Technology Data Exchange (ETDEWEB)

    Bandyopadhyay, Abhijit [Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Calcutta 700064 (India); Choubey, Sandhya [Scuola Internazionale Superiore di Studi Avanzati I-34014, Trieste (Italy); Goswami, Srubabati [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211019 (India); Gandhi, Raj [Harish-Chandra Research Institute, Chhatnag Road, Jhunsi, Allahabad 211019 (India); Roy, D P [Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400005 (India)

    2003-11-01

    We investigate the potential of 3 kiloton-years (kTy) of KamLAND data to further constrain the {delta}m{sup 2} and tan{sup 2}{theta} values compared to those presently allowed by existing KamLAND and global solar data. We study the extent, dependence and characteristics of this sensitivity in and around the two parts of the LMA region that are currently allowed. Our analysis with 3 kTy simulated spectra shows that KamLAND spectrum data by itself can constrain {delta}m{sup 2} with high precision. Combining the spectrum with global solar data further tightens the constraints on allowed values of tan{sup 2}{theta} and {delta}m{sup 2}. We also study the effects of future neutral current data with a total error of 7% from the Sudbury Neutrino Observatory. We find that these future measurements offer the potential of considerable precision in determining the oscillation parameters (specially the mass parameter)

  10. Mantle geoneutrinos in KamLAND and Borexino

    CERN Document Server

    Fiorentini, G; Lisi, E; Mantovani, F; Rotunno, A M

    2012-01-01

    The KamLAND and Borexino experiments have observed, each at ~4 sigma level, signals of electron antineutrinos produced in the decay chains of thorium and uranium in the Earth's crust and mantle (Th and U geoneutrinos). Various pieces of geochemical and geophysical information allow an estimation of the crustal geoneutrino flux components with relatively small uncertainties. The mantle component may then be inferred by subtracting the estimated crustal flux from the measured total flux. To this purpose, we analyze in detail the experimental Th and U geoneutrino event rates in KamLAND and Borexino, including neutrino oscillation effects. We estimate the crustal flux at the two detector sites, using state-of-the-art information about the Th and U distribution on global and local scales. We find that crust-subtracted signals show hints of a residual mantle component, emerging at ~2.4 sigma level by combining the KamLAND and Borexino data. The inferred mantle flux slightly favors scenarios with relatively high Th ...

  11. How much Uranium is in the Earth? Predictions for geo-neutrinos at KamLAND

    CERN Document Server

    Fiorentini, G; Mantovani, F; Vannucci, R; Fiorentini, Gianni; Lissia, Marcello; Mantovani, Fabio; Vannucci, Riccardo

    2005-01-01

    Geo-neutrino detection can determine the amount of long-lived radioactive elements within our planet, thus providing a direct test of the Bulk Silicate Earth (BSE) model and fixing the radiogenic contribution to the terrestrial heat. We present a prediction for the geo-neutrino signal at KamLAND as a function of the Uranium mass in the Earth. The prediction is based on global mass balance, supplemented by a detailed geochemical and geophysical study of the region near the detector. The prediction is weakly dependent on mantle modeling. If BSE is correct, Uranium geo-neutrinos will produce between 25 and 35 events per year and 10^32 protons at Kamioka.

  12. Solar neutrino oscillation parameters after first KamLAND results

    CERN Document Server

    Fogli, G L; Marrone, A; Montanino, D; Palazzo, A; Rotunno, A M

    2003-01-01

    We analyze the energy spectrum of reactor neutrino events recently observed in the Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) and combine them with solar and terrestrial neutrino data, in the context of two- and three-family active neutrino oscillations. In the 2-neutrino case, we find that the solution to the solar neutrino problem at large mixing angle (LMA) is basically split into two sub-regions, that we denote as LMA-I and LMA-II. The LMA-I solution, characterized by lower values of the squared neutrino mass gap, is favored by the global data fit. This picture is not significantly modified in the 3-neutrino mixing case. A brief discussion is given about the discrimination of the LMA-I and LMA-II solutions with future KamLAND data. In both the 2- and 3-neutrino cases, we present a detailed analysis of the post-KamLAND bounds on the oscillation parameters.

  13. White paper: CeLAND - Investigation of the reactor antineutrino anomaly with an intense 144Ce-144Pr antineutrino source in KamLAND

    CERN Document Server

    Gando, A; Ichimura, K; Ikeda, H; Inoue, K; Kibe, Y; Kishimoto, Y; Koga, M; Minekawa, Y; Mitsui, T; Morikawa, T; Nagai, N; Nakamura, K Nakajima K; Narita, K; Shimizu, I; Shimizu, Y; Shirai, J; Suekane, F; Suzuki, A; Takahashi, H; Takahashi, N; Takemoto, Y; Tamae, K; Watanabe, H; Xu, B D; Yabumoto, H; Yoshida, H; Yoshida, S; Berger, B E; Cribier, M; Decowski, P; Detwiler, J A; Durero, M; Dwyer, D; Efremenko, Y; Enomoto, S; Fischer, V; Fujikawa, B K; Gaffiot, J; Gelis, V M; Karwowski, H J; Kolomensky, Yu G; Kornoukhov, N; Lasserre, T; Learned, J G; Letourneau, A; Lhuillier, D; Maricic, J; Markoff, D M; Matsuno, S; Mention, G; Milincic, R; O'Donnell, T; Saldikov, I S; Scola, L; Tikhomirov, G V; Veyssiere, Ch; Vivier, M

    2013-01-01

    We propose to test for short baseline neutrino oscillations, implied by the recent reevaluation of the reactor antineutrino flux and by anomalous results from the gallium solar neutrino detectors. The test will consist of producing a 75 kCi 144Ce - 144Pr antineutrino source to be deployed in the Kamioka Liquid Scintillator Anti-Neutrino Detector (KamLAND). KamLAND's 13m diameter target volume provides a suitable environment to measure energy and position dependence of the detected neutrino flux. A characteristic oscillation pattern would be visible for a baseline of about 10 m or less, providing a very clean signal of neutrino disappearance into a yet-unknown, "sterile" state. Such a measurement will be free of any reactor-related uncertainties. After 1.5 years of data taking the Reactor Antineutrino Anomaly parameter space will be tested at > 95% C.L.

  14. Disappearing neutrinos at KamLAND suport the case for neutrino mass

    CERN Multimedia

    Johnson, G

    2002-01-01

    Measurements from KamLAND, show that anti-neutrinos emanating from nearby nuclear reactors are "disappearing," which indicates they have mass and can oscillate or change from one type to another (2 pages)

  15. On the origin of the discrepancy between the expected and observed results at KamLAND

    CERN Document Server

    Slad, L M

    2016-01-01

    After an elegant solution of the solar neutrino problem was found on the basis of a hypothesis of semiweak interaction between electron neutrinos and nucleons, a question has appeared about the origin of the difference between the expected results and the ones observed at KamLAND. We argue for significant role of light attenuation in the KamLAND liquid scintillator which has not been taken into account in theoretical calculations of the observability of expected events $\\bar{\

  16. On the measurement of solar neutrino oscillation parameters with KamLAND

    Energy Technology Data Exchange (ETDEWEB)

    Bandyopadhyay, Abhijit; Choubey, Sandhya; Goswami, Srubabati; Petcov, S.T

    2004-02-12

    A new reactor power plant Shika-2, with a power of approximately 4 GW and at a distance of about 88 km from the KamLAND detector is scheduled to start operating in March 2006. We study the impact of the {nu}-bar{sub e} flux from this reactor on the sensitivity of the KamLAND experiment to the solar neutrino oscillation parameters. We present results on prospective determination of {delta}m{sup 2}{sub o} and sin{sup 2}{theta}{sub o} using the combined data from KamLAND and the solar neutrino experiments, including the effect of the Shika-2 contribution to the KamLAND signal and the latest data from the salt enriched phase of the SNO experiment. We find that contrary to the expectations, the addition of the Shika-2 reactor flux does not improve the sin{sup 2}{theta}{sub o} sensitivity of KamLAND, while the ambiguity in {delta}m{sup 2}{sub o} measurement may even increase, as a result of the averaging effect between Kashiwazaki and the Shika-2 reactor contributions to the KamLAND signal.

  17. Update of the solar neutrino oscillation analysis with the 766 Ty KamLAND spectrum

    CERN Document Server

    Bandyopadhyay, A; Goswami, S; Petcov, S T; Roy, D P; Bandyopadhyay, Abhijit; Choubey, Sandhya; Goswami, Srubabati

    2004-01-01

    We investigate the impact of the observed spectral distortion in the 766.3 Ty KamLAND data in sharpening the allowed areas in solar neutrino oscillation parameter space. We study the robustness of the allowed regions and mutual consistency between different data sets by doing two generation neutrino oscillation global fits by removing one of the solar neutrino experiments from the analysis. We also examine the change if any in the bound on $\\theta_{13}$ from a three generation analysis with the inclusion of the new KamLAND data. We find that the precision of $\\Delta m^2_{21}$ improves significantly with the new KamLAND data in both two and three generation analysis but there is still scope for improvement for the precision of $\\theta_{12}$. The combined solar and KamLAND data excludes the high-LMA solution at the 4$\\sigma$ level in a one parameter fit. The maximal mixing solution is disfavoured to a greater extent by the new KamLAND data and the solar + KamLAND combination excludes it at about 6$\\sigma$. We d...

  18. An Update on Progress at KamLAND

    CERN Document Server

    Dazeley, S A

    2002-01-01

    The first generation of solar neutrino experiments narrowed the allowed flavor mixing and mass parameter solutions (for nu_e nu_x) to a few isolated regions of sin^2*2*theta - delta M^2 parameter space. Recently, the Small Mixing Angle (SMA) solution, and the ``just so'' solutions have been disfavored by results from Super-Kamiokande and SNO. The Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) recently became operational, and is particularly sensitive to the Large Mixing Angle (LMA) region. We believe the background impurity levels in the detector are low enough to conduct a successful experiment. The stability of the central balloon and PMTs has also been confirmed.

  19. Constraints on theta 13 from a three-flavor oscillation analysis of reactor antineutrinos at KamLAND

    NARCIS (Netherlands)

    Gando, A.; et al., [Unknown; Decowski, M.P.

    2011-01-01

    We present new constraints on the neutrino oscillation parameters Δm212, θ12, and θ13 from a three-flavor analysis of solar and KamLAND data. The KamLAND data set includes data acquired following a radiopurity upgrade and amounts to a total exposure of 3.49×1032 target-proton-year. Under the assumpt

  20. Precision Measurement of Neutrino Oscillation Parameters with KamLAND

    Energy Technology Data Exchange (ETDEWEB)

    O' Donnell, Thomas [Univ. of California, Berkeley, CA (United States)

    2011-12-01

    This dissertation describes a measurement of the neutrino oscillation parameters m2 21, θ12 and constraints on θ13 based on a study of reactor antineutrinos at a baseline of ~ 180 km with the KamLAND detector. The data presented here was collected between April 2002 and November 2009, and amounts to a total exposure of 2.64 ± 0.07 × 1032 proton-years. For this exposure we expect 2140 ± 74(syst) antineutrino candidates from reactors, assuming standard model neutrino behavior, and 350±88(syst) candidates from background. The number observed is 1614. The ratio of background-subtracted candidates observed to expected is (NObs - NBkg)/ (NExp) = 0.59 ± 0.02(stat) ± 0.045(syst) which confirms reactor neutrino disappearance at greater than 5σ significance. Interpreting this deficit as being due to neutrino oscillation, the best-fit oscillation parameters from a three-flavor analysis are m2 21= 7.60+0.20 -0.19×10-5eV2, θ12 = 32.5 ± 2.9 degrees and sin2 θ13 = 0.025+0.035 -0.035, the 95% confidence-level upper limit on sin2 θ13 is sin2 θ13 < 0.083. Assuming CPT invariance, a combined analysis of KamLAND and solar neutrino data yields best-fit values: m2 21 = 7.60+0.20 -0.20 × 10-5eV2, θ12 = 33.5+1.0 -1.1 degrees, and sin2 θ13 = 0.013 ± 0.028 or sin2 θ13 < 0.06 at the 95% confidence level.

  1. Experimental Study Of Terrestrial Electron Anti-neutrinos With Kamland

    CERN Document Server

    Tolich, N R

    2005-01-01

    The analysis presented here uses Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) to measure the rate of electron anti-neutrinos, ne&d1;' s , produced from terrestrial 238U and 212Th. 238U and 212Th are thought to be the main heat source driving mantle convection in the Earth, which in turn is responsible for plate tectonics. The total terrestrial 238U and 212Th content has been estimated from Earth models and rock samples from a very small fraction of the Earth. Until now there have been no direct measurements. Since ne&d1;' s have an exceedingly small cross section, they propagate undisturbed in the Earth interior, and their measurement near the Earth surface can be used to gain information on their sources. Based on a total of (2.63 ± 0.19) × 1031 target proton-years (0.506 kton- years), the 90% confidence interval for the total number of terrestrial 238U and 212Th ne&d1;' s detected is 4 to 40. This is consistent with the best models of terrestrial 23...

  2. Measurement of Neutrino Oscillation with KamLAND: Evidence of Spectral Distortion

    CERN Document Server

    Araki, T; Enomoto, S; Furuno, K; Ichimura, K; Ikeda, H; Inoue, K; Ishihara, K; Iwamoto, T; Kawashima, T; Kishimoto, Y; Koga, M; Koseki, Y; Maeda, T; Mitsui, T; Motoki, M; Nakajima, K; Ogawa, H; Owada, K; Ricol, J S; Shimizu, I; Shirai, J; Suekane, F; Suzuki, A; Tada, K; Tajima, O; Tamae, K; Tsuda, Y; Watanabe, H; Busenitz, J; Classen, T; Djurcic, Z; Keefer, G; McKinny, K; Mei, D M; Piepke, A; Yakushev, E; Berger, B E; Chan, Y D; Decowski, M P; Dwyer, D A; Freedman, S J; Fu, Y; Fujikawa, B K; Goldman, J; Gray, F; Heeger, K M; Lesko, K T; Luk, K B; Murayama, H; Poon, A W P; Steiner, H M; Winslow, L A; Horton-Smith, G A; Mauger, C; McKeown, R D; Vogel, P; Lane, C E; Miletic, T; Gorham, P W; Guillian, G; Learned, J G; Maricic, J; Matsuno, S; Pakvasa, S; Dazeley, S; Hatakeyama, S; Rojas, A; Svoboda, R; Dieterle, B D; Detwiler, J; Gratta, G; Ishii, K; Tolich, N; Uchida, Y; Batygov, M; Bugg, W; Efremenko, Yu V; Kamyshkov, Yu A; Kozlov, A; Nakamura, Y; Gould, C R; Karwowski, H J; Markoff, D M; Messimore, J A; Nakamura, K; Rohm, R M; Tornow, W; Wendell, R; Young, A R; Chen, M J; Wang, Y F; Piquemal, F

    2005-01-01

    We present an improved measurement of the oscillation between the first two neutrino families based on a 766.3 ton-year exposure of KamLAND to reactor anti-neutrinos. KamLAND observes 258 events with nue-bar energies above 3.4MeV compared to 365.2 events expected in the absence of neutrino oscillation. The confidence level for reactor nue-bar disappearance is now 99.995%. The observed energy spectrum disagrees with the expected spectral shape in the absence of neutrino oscillation at the 99.9% confidence level but agrees with the distortion expected from nue-bar oscillation effects. A two-neutrino oscillation analysis of the KamLAND data gives a best-fit point at DeltaMSq=8.3times10^{-5}eV^2 and tan{^2}theta=0.41. A global analysis of data from KamLAND and solar neutrino experiments yields DeltaMSq=8.2^{+0.6}_{-0.5}times10^{-5}eV^2 and tan^{2}theta =0.40^{+0.09}_{-0.07}, the most precise determination to date.

  3. Update of the solar neutrino oscillation analysis with the 766 Ty KamLAND spectrum

    Energy Technology Data Exchange (ETDEWEB)

    Bandyopadhyay, Abhijit [Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Calcutta 700 064 (India); Choubey, Sandhya [INFN, Sezione di Trieste, Trieste (Italy) and Scuola Internazionale Superiore di Studi Avanzati, I-34014 Trieste (Italy)]. E-mail: sandhya@he.sissa.it; Goswami, Srubabati [Harish-Chandra Research Institute, Chhatnag Road, Jhusi, Allahabad 211 019 (India); Petcov, S.T. [Scuola Internazionale Superiore di Studi Avanzati, I-34014 Trieste (Italy); INFN, Sezione di Trieste, Trieste (Italy); Institute of Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Sofia (Bulgaria); Roy, D.P. [Abdus Salam International Centre for Theoretical Physics, I-34100 Trieste (Italy); Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai 400 005 (India)

    2005-02-17

    We investigate the impact of the 766.3 Ty KamLAND spectrum data on the determination of the solar neutrino oscillation parameters. We show that the observed spectrum distortion in the KamLAND experiment firmly establishes {delta}m{sub 21}{sup 2} to lie in the low-LMA solution region. The high-LMA solution is excluded at more than 4{sigma} by the global solar neutrino and KamLAND spectrum data. The maximal solar neutrino mixing is ruled out at 6{sigma} level. The 3{sigma} allowed region in the {delta}m{sub 21}{sup 2}-sin{sup 2}{theta}{sub 12} plane is found to be remarkably stable with respect to leaving out the data from one of the solar neutrino experiments from the global analysis. We perform a three flavor neutrino oscillation analysis of the global solar neutrino and KamLAND spectrum data as well. The 3{sigma} upper limit on sin{sup 2}{theta}{sub 13} is found to be sin{sup 2}{theta}{sub 13}<0.055. We derive predictions for the CC to NC event rate ratio and day-night (D-N) asymmetry in the CC event rate, measured in the SNO experiment, and for the suppression of the event rate in the BOREXINO and LowNu experiments. Prospective high precision measurements of the solar neutrino oscillation parameters are also discussed.

  4. On the Measurement of Solar Neutrino Oscillation Parameters with KamLAND

    CERN Document Server

    Bandyopadhyay, A; Goswami, S; Petcov, S T; Bandyopadhyay, Abhijit; Choubey, Sandhya; Goswami, Srubabati

    2004-01-01

    A new reactor power plant Shika-2, with a power of approximately 4 GW and at a distance of about 88 km from the KamLAND detector is scheduled to start operating in March 2006. We study the impact of the $\\bar\

  5. A compact ultra-clean system for deploying radioactive sources inside the KamLAND detector

    NARCIS (Netherlands)

    Banks, T.I.; Freedman, S.J.; Wallig, J.; Ybarrolaza, N.; Gando, A.; Gando, Y.; Ikeda, H.; Inoue, K.; Kishimoto, Y.; Koga, M.; Mitsui, T.; Nakamura, K.; Shimizu, I.; Shirai, J.; Suzuki, A.; Takemoto, Y.; Tamae, K.; Ueshima, K.; Watanabe, H.; Xu, B.D.; Yoshida, H.; Yoshida, S.; Kozlov, A.; Grant, C.; Keefer, G.; Piepke, A.; Bloxham, T.; Fujikawa, B.K.; Han, K.; Ichimura, K.; Murayama, H.; O'Donnell, T.; Steiner, H.M.; Winslow, L.A.; Dwyer, D.A.; McKeown, R.D.; Zhang, C.; Berger, B.E.; Lane, C.E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J.G.; Matsuno, S.; Sakai, M.; Horton-Smith, G.A.; Downum, K.E.; Gratta, G.; Efremenko, Y.; Perevozchikov, O.; Karwowski, H.J.; Markoff, D.M.; Tornow, W.; Heeger, K.M.; Detwiler, J.A.; Enomoto, S.; Decowski, M.P.

    2015-01-01

    We describe a compact, ultra-clean device used to deploy radioactive sources along the vertical axis of the KamLAND liquid-scintillator neutrino detector for purposes of calibration. The device worked by paying out and reeling in precise lengths of a hanging, small-gauge wire rope (cable); an assort

  6. Search for extraterrestrial antineutrino sources with the KamLAND detector

    NARCIS (Netherlands)

    Abe, S.; et al., [Unknown; Decowski, M.P.

    2012-01-01

    We present the results of a search for extraterrestrial electron antineutrinos ( 's) in the energy range 8.3 MeV < Eve < 31.8 MeV using the KamLAND detector. In an exposure of 4.53 kton-year, we identify 25 candidate events. All of the candidate events can be attributed to background, most important

  7. Solving the Solar Neutrino Puzzle with KamLAND and Solar Data

    CERN Document Server

    De Gouvêa, A; Gouv\\^ea, Andr\\'e de

    2001-01-01

    We study what will be learnt about the solar neutrino puzzle and solar neutrino oscillations once the data from the KamLAND reactor neutrino experiment (soon to become available) are combined with those from the current solar neutrino experiments. We find that, in agreement with previous estimates, if the solution to the solar neutrino puzzle falls on the LMA region, KamLAND should be able to ``pin-point'' the right solution with unprecedented accuracy after a few years of data taking. Furthermore, the light side ($\\theta\\pi/4$) at the 95% confidence level (CL) for most of the LMA region allowed by the current data at the 99% CL, while the addition of the KamLAND data need not improve our ability to limit a sterile component in ``solar'' oscillations. If KamLAND does not see an oscillation signal, the solar data would point to the LOW/VAC regions, while the SMA region would still lurk at the two sigma CL, meaning we would probably have to wait for Borexino data in order to finally piece the solar neutrino puz...

  8. Poly-ϵ-caprolactone/chitosan nanoparticles provide strong adjuvant effect for hepatitis B antigen.

    Science.gov (United States)

    Jesus, Sandra; Soares, Edna; Borchard, Gerrit; Borges, Olga

    2017-10-01

    This work aims to investigate the adjuvant effect of poly-ϵ-caprolactone/chitosan nanoparticles (NPs) for hepatitis B surface antigen (HBsAg) and the plasmid DNA encoding HBsAg (pRC/CMV-HBs). Both antigens were adsorbed onto preformed NPs. Vaccination studies were performed in C57BL/6 mice. Transfection efficiency was investigated in A549 cell line. HBsAg-adsorbed NPs generated strong anti-HBsAg IgG titers, mainly of IgG1 isotype, and induced antigen-specific IFN-γ and IL-17 secretion by spleen cells. The addition of pRC/CMV-HBs to the HBsAg-adsorbed NPs inhibited IL-17 secretion but had minor effect on IFN-γ levels. Lastly, pRC/CMV-HBs-loaded NPs generated a weak serum antibody response. Poly-ϵ-caprolactone/chitosan NPs provide a strong humoral adjuvant effect for HBsAg and induce a Th1/Th17-mediated cellular immune responses worth explore for hepatitis B virus vaccination.

  9. CeLAND: search for a 4th light neutrino state with a 3 PBq 144Ce-144Pr electron antineutrino generator in KamLAND

    CERN Document Server

    Gando, A; Hayashida, S; Ikeda, H; Inoue, K; Ishidoshiro, K; Ishikawa, H; Koga, M; Matsuda, R; Matsuda, S; Mitsui, T; Motoki, D; Nakamura, K; Oki, Y; Otani, M; Shimizu, I; Shirai, J; Suekane, F; Suzuki, A; Takemoto, Y; Tamae, K; Ueshima, K; Watanabe, H; Xu, B D; Yamada, S; Yamauchi, Y; Yoshida, H; Cribier, M; Durero, M; Fischer, V; Gaffiot, J; Jonqueres, N; Kouchner, A; Lasserre, T; Leterme, D; Letourneau, A; Lhuillier, D; Mention, G; Rampal, G; Scola, L; Veyssiere, Ch; Vivier, M; Yala, P; Berger, B E; Kozlov, A; Banks, T; Dwyer, D; Fujikawa, B K; Han, K; Kolomensky, Yu G; Mei, Y; O'Donnell, T; Decowski, P; Markoff, D M; Yoshida, S; Kornoukhov, V N; Gelis, T V M; Tikhomirov, G V; Learned, J G; Maricic, J; Matsuno, S; Milincic, R; Karwowski, H J; Efremenko, Y; Detwiler, A; Enomoto, S

    2013-01-01

    The reactor neutrino and gallium anomalies can be tested with a 3-4 PBq (75-100 kCi scale) 144Ce-144Pr antineutrino beta-source deployed at the center or next to a large low-background liquid scintillator detector. The antineutrino generator will be produced by the Russian reprocessing plant PA Mayak as early as 2014, transported to Japan, and deployed in the Kamioka Liquid Scintillator Anti-Neutrino Detector (KamLAND) as early as 2015. KamLAND's 13 m diameter target volume provides a suitable environment to measure the energy and position dependence of the detected neutrino flux. A characteristic oscillation pattern would be visible for a baseline of about 10 m or less, providing a very clean signal of neutrino disappearance into a yet-unknown, sterile neutrino state. This will provide a comprehensive test of the electron dissaperance neutrino anomalies and could lead to the discovery of a 4th neutrino state for Delta_m^2 > 0.1 eV^2 and sin^2(2theta) > 0.05.

  10. Parameter Limits for Neutrino Oscillation with Decoherence in KamLAND

    CERN Document Server

    Gomes, G Balieiro; de Holanda, P C; Oliveira, R L N

    2016-01-01

    In the framework of quantum open systems we analyze data from KamLAND by using a model that considers neutrino oscillation in a three-family approximation with the inclusion of the decoherence effect. Using a $\\chi^2$ test we find new limits for the decoherence parameter which we call $\\gamma$, considering the most recent data by KamLAND. Assuming an energy dependence of the type $ \\gamma = \\gamma_0 \\left( E/E_0 \\right) ^n$, in 95 \\% C.L. the limits found are $3.7 \\times 10^{-27} GeV$ for $ n=-1$, $6.8 \\times 10^{-22} GeV$ for $ n=0$, and $1.5 \\times 10^{-16} GeV$ for $ n=1 $ on the energy dependence.

  11. Measurement of the 8B solar neutrino flux with the KamLAND liquid scintillator detector

    NARCIS (Netherlands)

    Abe, S.; et al., [Unknown; Decowski, M.P.

    2011-01-01

    We report a measurement of the neutrino-electron elastic scattering rate from 8B solar neutrinos based on a 123 kton-day exposure of KamLAND. The background-subtracted electron recoil rate, above a 5.5-MeV analysis threshold is 1.49 ± 0.14(stat) ± 0.17(syst) events per kton-day. Interpreted as due t

  12. Providing strong Security and high privacy in low-cost RFID networks

    DEFF Research Database (Denmark)

    David, Mathieu; Prasad, Neeli R.

    2009-01-01

    Since the dissemination of Radio Frequency IDentification (RFID) tags is getting larger and larger, the requirement for strong security and privacy is also increasing. Low-cost and ultra-low-cost tags are being implemented on everyday products, and their limited resources constraints the security...

  13. Searches for sterile component with solar neutrinos and KamLAND

    CERN Document Server

    De Holanda, P C

    2002-01-01

    Possible mixing of the active and sterile neutrinos has been considered both in the single Delta m^2 approximation and in the case of more than one Delta m^2. We perform global fit of the available solar neutrino data with free boron neutrino flux in the single Delta m^2 context. The best fit value corresponds to zero fraction of sterile component eta=0. We get the upper bounds: eta<0.26 (0.64) at 1\\sigma (3 sigma). Due to degeneracy of parameters no one individual experiment restricts eta. The bound appears as an interplay of the SNO and Gallium as well as SuperKamiokande data. Future measurements of the NC/CC ratio at SNO can strengthen the bound down to eta<0.5 (3 sigma). If KamLAND confirms the LMA solution with its best fit point a combined analysis of the KamLAND and solar neutrino results will lead to eta<0.19 (0.56) at 1 sigma (3 sigma). We find that existence of sterile neutrino can explain the intermediate value of suppression of the KamLAND event rate: R_{KL}~0.75-0.90 in the case when mor...

  14. LMA MSW solution of the solar neutrino problem and first KamLAND results

    CERN Document Server

    De Holanda, P C

    2003-01-01

    The first KamLAND results are in a very good agreement with the predictions made on the basis of the solar neutrino data and the LMA realization of the MSW mechanism. We perform a combined analysis of the KamLAND (rate, spectrum) and the solar neutrino data with a free boron neutrino flux f_B. The best fit values of neutrino parameters are Delta m^2 = 7.3e-5 eV^2, tg^2 theta = 0.41 and f_B = 1.05 with the 1 sigma intervals: Delta m^2 = (6.2 - 8.4)e-5 eV^2, tg^2 theta = 0.33 - 0.54. We find the 3 sigma upper bounds: Delta m^2 4e-5 eV^2. At 99% C.L. the KamLAND spectral result splits the LMA region into two parts with the preferred one at Delta m^2 < 1e-4 eV^2. The higher Delta m^2 region is accepted at about 2 sigma level. We show that effects of non-zero 13-mixing, sin^2 theta_{13} < 0.04, are small leading to slight improvement of the fit in higher Delta m^2 region. In the best fit point we predict for SNO: CC/NC = 0.33 +0.05-0.03 and A_{DN}(SNO) = 2.8+-0.8 % (68% C.L.), and A_{DN}(SNO) < 9 % at th...

  15. Determination of the age of the earth from Kamland measurement of geo-neutrinos

    OpenAIRE

    Mohanty, Subhendra

    2003-01-01

    The low energy component of the antineutrino spectrum observed in the recent Kamland experiment has significant contribution from the radioactive decay of $^{238}U$ and $^{232}Th$ in the crust and mantle of the earth. By taking the ratio of the antineutrino events obeserved in two different energy ranges we can determine the present value $[Th/U]$ independent of the U,Th distribution in the earth. Comparing with the r-process initial value of $[Th/U]_0$ we determine the age of the earth as a ...

  16. Combined analysis of KamLAND and Borexino neutrino signals from Th and U decays in the Earth's interior

    CERN Document Server

    Fogli, G L; Palazzo, A; Rotunno, A M

    2010-01-01

    The KamLAND and Borexino experiments have detected electron antineutrinos produced in the decay chains of natural thorium and uranium (Th and U geoneutrinos). We analyze the energy spectra of current geoneutrino data in combination with solar and long-baseline reactor neutrino data, with marginalized three-neutrino oscillation parameters. We consider the case with unconstrained Th and U event rates in KamLAND and Borexino, as well as cases with fewer degrees of freedom, as obtained by successively assuming for both experiments a common Th/U ratio, a common scaling of Th+U event rates, and a chondritic Th/U value. In combination, KamLAND and Borexino can reject the null hypothesis (no geoneutrino signal) at 5 sigma. Interesting bounds or indications emerge on the Th+U geoneutrino rates and on the Th/U ratio, in broad agreement with typical Earth model expectations. Conversely, the results disfavor the hypothesis of a georeactor in the Earth's core, if its power exceeds a few TW. The interplay of KamLAND and Bo...

  17. Statistically improved Analysis of Neutrino Oscillation Data with the latest KamLAND result

    CERN Document Server

    Aliani, P; Torrente-Lujan, E

    2005-01-01

    We present an updated analysis of all available solar and reactor neutrino data, emphasizing in particular the totality of the KamLAND (314d live time) results and including for the first time the solar $SNO$ (391d live time, phase II NaCl-enhanced) spectrum data. As a novelty of the statistical analysis, we study the variability of the KamLand results with respect the use of diverse statistics. A new statistic, not used before is proposed. Moreover, in the analysis of the SNO spectrum a novel technique is used in order to include full correlated errors among bins. Combining all data, we obtain the following best-fit parameters: we determine individual neutrino mixing parameters and their errors $ \\Delta m^2= 8.2\\pm 0.08\\times 10^{-5} \\eV^2,\\quad \\tan^2\\theta= 0.50^{+0.12}_{-0.07}.$ The impact of these results is discussed. We also estimate the individual elements of the neutrino mass matrix. In the framework of three neutrino oscillations we obtain the mass matrix: \\begin{eqnarray}M&=& eV \\pmatrix{1....

  18. Prospects of probing $\\theta_{13}$ and neutrino mass hierarchy by Supernova Neutrinos in KamLAND

    CERN Document Server

    Bandyopadhyay, A; Goswami, S; Kar, K; Bandyopadhyay, Abhijit; Choubey, Sandhya; Goswami, Srubabati; Kar, Kamales

    2003-01-01

    In this paper we study the physics potential of the KamLAND detector in probing neutrino oscillation parameters through observation of supernova neutrinos. In particular, we discuss the possibilities of probing the mixing angle $\\theta_{13}$ and determining the sign of $\\Delta m^2_{32}$ from the total charged current(CC) event rates on the proton and $^{12}{C}$ target, as well as from the CC spectra. We discuss the chances of probing the earth matter effect induced modulations from the observation of CC spectra in the different CC reactions in KamLAND and find the volume required to get a statistically significant signature of the earth matter effect in different energy bins. We also calculate the event rates expected in the neutral current (NC) reactions on Carbon and free proton and investigate if the charged current to neutral current ratios, which are free of the absolute luminosity uncertainty in the supernova neutrino fluxes, can be useful in probing the oscillation parameters.

  19. Measurement of the 8B Solar Neutrino Flux with KamLAND

    CERN Document Server

    Abe, S; Gando, A; Gando, Y; Ichimura, K; Ikeda, H; Inoue, K; Kibe, Y; Kimura, W; Kishimoto, Y; Koga, M; Minekawa, Y; Mitsui, T; Morikawa, T; Nagai, N; Nakajima, K; Nakamura, K; Nakamura, M; Narita, K; Shimizu, I; Shimizu, Y; Shirai, J; Suekane, F; Suzuki, A; Takahashi, H; Takahashi, N; Takemoto, Y; Tamae, K; Watanabe, H; Xu, B D; Yabumoto, H; Yonezawa, E; Yoshida, H; Yoshida, S; Enomoto, S; Kozlov, A; Murayama, H; Grant, C; Keefer, G; McKee, D; Piepke, A; Banks, T I; Bloxham, T; Detwiler, J A; Freedman, S J; Fujikawa, B K; Han, K; Kadel, R; O'Donnell, T; Steiner, H M; Winslow, L A; Dwyer, D A; Mauger, C; McKeown, R D; Zhang, C; Berger, B E; Lane, C E; Maricic, J; Miletic, T; Batygov, M; Learned, J G; Matsuno, S; Pakvasa, S; Sakai, M; Horton-Smith, G A; Tang, A; Downum, K E; Gratta, G; Tolich, K; Efremenko, Y; Kamyshkov, Y; Perevozchikov, O; Karwowski, H J; Markoff, D M; Tornow, W; Heeger, K M; Piquemal, F; Ricol, J -S; Decowski, M P

    2011-01-01

    We report a measurement of the neutrino-electron elastic scattering rate from 8B solar neutrinos based on a 123 kton-day exposure of KamLAND. The background-subtracted electron recoil rate, above a 5.5 MeV analysis threshold is 1.49+/-0.14(stat)+/-0.17(syst) events per kton-day. Interpreted as due to a pure electron flavor flux with a 8B neutrino spectrum, this corresponds to a spectrum integrated flux of 2.77+/-0.26(stat)+/-0.32(syst) x 10^6 cm^-2s^-1. The analysis threshold is driven by 208Tl present in the liquid scintillator, and the main source of systematic uncertainty is due to background from cosmogenic 11Be. The measured rate is consistent with existing measurements and with Standard Solar Model predictions which include matter enhanced neutrino oscillation.

  20. Measurement of the 8B Solar Neutrino Flux with KamLAND

    Energy Technology Data Exchange (ETDEWEB)

    Abe, S.; Furuno, K.; Gando, A.; Gando, Y.; Ichimura, K.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kimura, W.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Morikawa, T.; Nagai, N.; Nakajima, K.; Nakamura, K.; Nakamura, M.; Narita, K.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takahashi, H.; Takahashi, N.; Takemoto, Y.; Tamae, K.; Watanabe, H.; Xu, B.D.; Yabumoto, H.; Yonezawa, E.; Yoshida, H.; Yoshida, S.; Enomoto, S.; Kozlov, A.; Murayama, H.; Grant, C.; Keefer, G.; McKee, D.; Piepke, A.; Banks, T.I.; Bloxham, T.; Detwiler, J.A.; Freedman, S.J.; Fujikawa, B.K.; Han, K.; Kadel, R.; O' Donnell, T.; Steiner, H.M.; Winslow, L.A.; Dwyer, D.A.; Mauger, C.; McKeown, R.D.; Zhang, C.; Berger, B.E.; Lane, C.E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J.G.; Matsuno, S.; Pakvasa, S.; Sakai, M.; Horton-Smith, G.A.; Tang, A.; Downum, K.E.; Gratta, G.; Tolich, K.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H.J.; Markoff, D.M.; Tornow, W.; Heeger, K.M.; Piquemal, F.; Ricol, J.-S.; Decowski, M.P.

    2011-06-04

    We report a measurement of the neutrino-electron elastic scattering rate from {sup 8}B solar neutrinos based on a 123 kton-day exposure of KamLAND. The background-subtracted electron recoil rate, above a 5.5-MeV analysis threshold is 1.49 {+-} 0.14(stat) {+-} 0.17(syst) events per kton-day. Interpreted as due to a pure electron flavor flux with a {sup 8}B neutrino spectrum, this corresponds to a spectrum integrated flux of 2.77 {+-} 0.26(stat) {+-} 0.32(syst) x 10{sup 6} cm{sup -2}s{sup -1}. The analysis threshold is driven by {sup 208}Tl present in the liquid scintillator, and the main source of systematic uncertainty is due to background from cosmogenic {sup 11}Be. The measured rate is consistent with existing measurements and with standard solar model predictions which include matter-enhanced neutrino oscillation.

  1. A study of extraterrestrial antineutrino sources with the KamLAND detector

    Energy Technology Data Exchange (ETDEWEB)

    The KamLAND Collaboration; Gando, A.; Gando, Y.; Ichimura, K.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Morikawa, T.; Nagai, N.; Nakajima, K.; Nakamura, K.; Narita, K.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takahashi, H.; Takahashi, N.; Takemoto, Y.; Tamae, K.; Watanabe, H.; Xu, B. D.; Yabumoto, H.; Yoshida, H.; Yoshida, S.; Enomoto, S.; Kozlov, A.; Murayama, H.; Grant, C.; Keefer, G.; Piepke, A.; Banks, T. I.; Bloxham, T.; Detwiler, J. A.; Freedman, S. J.; Fujikawa, B. K.; Han, K.; Kadel, R.; O' Donnell, T.; Steiner, H. M.; Dwyer, D. A.; McKeown, R. D.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Sakai, M.; Horton-Smith, G. A.; Downum, K. E.; Gratta, G.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Heeger, K. M.; Decowski, M. P.

    2011-05-18

    We present the results of a search for extraterrestrial electron antineutrinos ({bar {nu}}{sub e}'s) in the energy range 8.3 MeV < E{sub {bar {nu}}}{sub e} < 30.8 MeV using the KamLAND detector. In an exposure of 4.53 kton-year, we identify 25 candidate events. All of the candidate events can be attributed to background, most importantly neutral current atmospheric neutrino interactions, setting an upper limit on the probability of {sup 8}B solar {nu}{sub e}'s converting into {bar {nu}}{sub e}'s at 5.3 x 10{sup -5} (90% C.L.). The present data also allows us to set more stringent limits on the diffuse supernova neutrino flux and on the annihilation rates for light dark matter particles.

  2. A compact ultra-clean system for deploying radioactive sources inside the KamLAND detector

    Energy Technology Data Exchange (ETDEWEB)

    Banks, T.I., E-mail: tbanks@berkeley.edu [Physics Department, University of California, Berkeley, CA 94720 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Freedman, S.J. [Physics Department, University of California, Berkeley, CA 94720 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Wallig, J.; Ybarrolaza, N. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Gando, A.; Gando, Y.; Ikeda, H. [Research Center for Neutrino Science, Tohoku University, Sendai 980-8578 (Japan); Inoue, K. [Research Center for Neutrino Science, Tohoku University, Sendai 980-8578 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Kishimoto, Y. [Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Research Center for Neutrino Science, Tohoku University, Sendai 980-8578 (Japan); Koga, M. [Research Center for Neutrino Science, Tohoku University, Sendai 980-8578 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Mitsui, T. [Research Center for Neutrino Science, Tohoku University, Sendai 980-8578 (Japan); Nakamura, K. [Research Center for Neutrino Science, Tohoku University, Sendai 980-8578 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI), University of Tokyo, Kashiwa, Chiba 277-8583 (Japan); Shimizu, I.; Shirai, J.; Suzuki, A.; Takemoto, Y.; Tamae, K.; Ueshima, K.; Watanabe, H.; Xu, B.D. [Research Center for Neutrino Science, Tohoku University, Sendai 980-8578 (Japan); and others

    2015-01-01

    We describe a compact, ultra-clean device used to deploy radioactive sources along the vertical axis of the KamLAND liquid-scintillator neutrino detector for purposes of calibration. The device worked by paying out and reeling in precise lengths of a hanging, small-gauge wire rope (cable); an assortment of interchangeable radioactive sources could be attached to a weight at the end of the cable. All components exposed to the radiopure liquid scintillator were made of chemically compatible UHV-cleaned materials, primarily stainless steel, in order to avoid contaminating or degrading the scintillator. To prevent radon intrusion, the apparatus was enclosed in a hermetically sealed housing inside a glove box, and both volumes were regularly flushed with purified nitrogen gas. An infrared camera attached to the side of the housing permitted real-time visual monitoring of the cable's motion, and the system was controlled via a graphical user interface.

  3. A compact ultra-clean system for deploying radioactive sources inside the KamLAND detector

    CERN Document Server

    Banks, T I; Wallig, J; Ybarrolaza, N; Gando, A; Gando, Y; Ikeda, H; Inoue, K; Kishimoto, Y; Koga, M; Mitsui, T; Nakamura, K; Shimizu, I; Shirai, J; Suzuki, A; Takemoto, Y; Tamae, K; Ueshima, K; Watanabe, H; Xu, B D; Yoshida, H; Yoshida, S; Kozlov, A; Grant, C; Keefer, G; Piepke, A; Bloxham, T; Fujikawa, B K; Han, K; Ichimura, K; Murayama, H; O'Donnell, T; Steiner, H M; Winslow, L A; Dwyer, D A; McKeown, R D; Zhang, C; Berger, B E; Lane, C E; Maricic, J; Miletic, T; Batygov, M; Learned, J G; Matsuno, S; Sakai, M; Horton-Smith, G A; Downum, K E; Gratta, G; Efremenko, Y; Perevozchikov, O; Karwowski, H J; Markoff, D M; Tornow, W; Heeger, K M; Detwiler, J A; Enomoto, S; Decowski, M P

    2014-01-01

    We describe a compact, ultra-clean device used to deploy radioactive sources along the vertical axis of the KamLAND liquid-scintillator neutrino detector for purposes of calibration. The device worked by paying out and reeling in precise lengths of a hanging, small-gauge wire rope (cable); an assortment of interchangeable radioactive sources could be attached to a weight at the end of the cable. All components exposed to the radiopure liquid scintillator were made of chemically compatible UHV-cleaned materials, primarily stainless steel, in order to avoid contaminating or degrading the scintillator. To prevent radon intrusion, the apparatus was enclosed in a hermetically sealed housing inside a glove box, and both volumes were regularly flushed with purified nitrogen gas. An infrared camera attached to the side of the housing permitted real-time visual monitoring of the cable's motion, and the system was controlled via a graphical user interface.

  4. Laboratory Studies on the Removal of Radon-Born Lead from KamLAND's Organic Liquid Scintillator

    CERN Document Server

    Keefer, G; Piepke, A; Ebihara, T; Ikeda, H; Kishimoto, Y; Kibe, Y; Koseki, Y; Ogawa, M; Shirai, J; Takeuchi, S; Mauger, C; Zhang, C; Schweitzer, G; Berger, B E; Dazeley, S; Decowski, M P; Detwiler, J A; Djurcic, Z; Dwyer, D A; Efremenko, Y; Enomoto, S; Freedman, S J; Fujikawa, B K; Furuno, K; Gando, A; Gando, Y; Gratta, G; Hatakeyama, S; Heeger, K M; Hsu, L; Ichimura, K; Inoue, K; Iwamoto, T; Kamyshkov, Y; Karwowski, H J; Koga, M; Kozlov, A; Lane, C E; Learned, J G; Maricic, J; Marko, D M; Matsuno, S; McKee, D; McKeown, R D; Miletic, T; Mitsui, T; Motoki, M; Nakajima, K; Nakamura, K; O'Donnell, T; Ogawa, H; Piquemal, F; Ricol, J -S; Shimizu, I; Suekane, F; Suzuki, A; Svoboda, R; Tajima, O; Takemoto, Y; Tamae, K; Tolich, K; Tornow, W; Watanabe, Hideki; Watanabe, Hiroko; Winslow, L A; Yoshida, S

    2013-01-01

    The removal of radioactivity from liquid scintillator has been studied in preparation of a low background phase of KamLAND. This paper describes the methods and techniques developed to measure and efficiently extract radon decay products from liquid scintillator. We report the radio-isotope reduction factors obtained when applying various extraction methods. During this study, distillation was identified as the most efficient method for removing radon daughters from liquid scintillator.

  5. Search for electron antineutrinos associated with gravitational wave events GW150914 and GW151226 using KamLAND

    CERN Document Server

    Gando, A; Hachiya, T; Hayashi, A; Hayashida, S; Ikeda, H; Inoue, K; Ishidoshiro, K; Karino, Y; Koga, M; Matsuda, S; Mitsui, T; Nakamura, K; Obara, S; Oura, T; Ozaki, H; Shimizu, I; Shirahata, Y; Shirai, J; Suzuki, A; Takai, T; Tamae, K; Teraoka, Y; Ueshima, K; Watanabe, H; Kozolov, A; Takemoto, Y; Yoshida, S; Fushimi, K; Piepke, A; Banks, T I; Berger, B E; Fujikawa, B K; O'Donnell, T; Learned, J G; Maricic, J; Sakai, M; Winslow, L A; Krupczak, E; Ouellet, J; Efremenko, Y; Karwowski, H J; Markoff, D M; Tornow, W; Detwiler, J A; Enomoto, S; Decowski, M P

    2016-01-01

    We present a search for low energy antineutrino events coincident with the gravitational wave events GW150914 and GW151226, and the candidate event LVT151012 using KamLAND, a kiloton-scale antineutrino detector. We find no inverse beta-decay neutrino events within $\\pm 500$ seconds of either gravitational wave signal. This non-detection is used to constrain the electron antineutrino fluence and the luminosity of the astrophysical sources.

  6. Enhanced Constraints on theta13 from A Three-Flavor Oscillation Analysis of Reactor Antineutrinos at KamLAND

    Energy Technology Data Exchange (ETDEWEB)

    The KamLAND Collaboration; Gando, A.; Gando, Y.; Ichimura, K.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Morikawa, T.; Nagai, N.; Nakajima, K.; Nakamura, K.; Narita, K.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takahashi, H.; Takahashi, N.; Takemoto, Y.; Tamae, K.; Watanabe, H.; Xu, B. D.; Yabumoto, H.; Yoshida, H.; Yoshida, S.; Enomoto, S.; Kozlov, A.; Murayama, H.; Grant, C.; Keefer, G.; Piepke, A.; Banks, T. I.; Bloxham, T.; Detwiler, J. A.; Freedman, S. J.; Fujikawa, B. K.; Han, K.; Kadel, R.; O' Donnell, T.; Steiner, H. M.; Dwyer, D. A.; McKeown, R. D.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Sakai, M.; Horton-Smith, G. A.; Downum, K. E.; Gratta, G.; Efremenko, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Heeger, K. M.; Decowski, M. P.

    2010-09-24

    We present new constraints on the neutrino oscillation parameters {Delta}m{sub 21}{sup 2}, {theta}{sub 12}, and {theta}{sub 13} from a three-flavor analysis of solar and KamLAND data. The KamLAND data set includes data acquired following a radiopurity upgrade and amounts to a total exposure of 3.49 x 10{sup 32} target-proton-year. Under the assumption of CPT invariance, a two-flavor analysis ({theta}{sub 13} = 0) of the KamLAND and solar data yields the best-fit values tan{sup 2} {theta}{sub 12} = 0.444{sub -0.030}{sup +0.036} and {Delta}m{sub 21}{sup 2} = 7.50{sub -0.20}{sup +0.19} x 10{sup -5} eV{sup 2}; a three-flavor analysis with {theta}{sub 13} as a free parameter yields the best-fit values tan{sup 2} {theta}{sub 12} = 0.452{sub -0.033}{sup +0.035}, {Delta}m{sub 21}{sup 2} = 7.50{sub -0.20}{sup +0.19} x 10{sup -5}eV{sup 2}, and sin{sup 2} {theta}{sub 13} = 0.020{sub -0.016}{sup +0.016}. This {theta}{sub 13} interval is consistent with other recent work combining the CHOOZ, atmospheric and long-baseline accelerator experiments. We also present a new global {theta}{sub 13} analysis, incorporating the CHOOZ, atmospheric and accelerator data, which indicates sin{sup 2} {theta}{sub 13} = 0.017{sub -0.009}{sup +0.010}, a nonzero value at the 93% C.L. This finding will be further tested by upcoming accelerator and reactor experiments.

  7. A Strong Promoter Provided with the Gene Encoding Arginyl-tRNA Synthetase(argS) from Escherichia coli.

    Science.gov (United States)

    Liu, Mo-Fang; Li, Tong; Yin, Zhao-Bao; Xu, Min-Gang; Wang, En-Duo; Wang, Yin-Lai

    2000-01-01

    Previous studies showed that the gene argS encoding the arginyl-tRNA synthetase(ArgRS) from Escherichia coli(E.coli), was overexpressed 1 000 folds in the E.coli transformant TG1/pUC-argS, while the gene leuS, encoding the leucyl-tRNA synthetase(LeuRS) from E.coli, was only overproduced 35-fold in the same case. To investigate why the expression of these two aminoacyl-tRNA synthetase genes is so different, a fused gene (termed parg-leuS) was constructed by replacement of the 5' flanking region of leuS to 5' flanking region of argS. In the E.coli transformant TG1/pUC-parg-leuS, the activity of LeuRS was only improved 8.5-fold, which was much lower than that of the transformant harboring the recombinant plasmid pUC18-leuS or pKK-leuS. However, by RNA dot hybridization the amount of mRNA produced in the transcription of parg-leuS was about 5 times than that of the wild type leuS, and was similar to that of pKK-leuS, suggesting that the promoter of argS is very strong. Analysis of the secondary structure around the initiation codon among three mRNAs showed that the secondary structure of the mRNA from parg-leuS was the strongest of the three mRNAs. From the results, it could be deduced that expression of the fused gene parg-leuS might be controlled at the translational level and the strong secondary structure of this mRNA may hinder translation initiation and result in a low translation efficiency.

  8. PIKA Provides an Adjuvant Effect to Induce Strong Mucosal and Systemic Humoral Immunity Against SARS-CoV

    Institute of Scientific and Technical Information of China (English)

    Wei-wei Gai; Yan Zhang; Di-han Zhou; Yao-qing Chen; Jing-yi Yang; Hui-min Yan

    2011-01-01

    Severe Acute Respiratory Syndrome(SARS)is a deadly infectious disease caused by SARS Coronavirus(SARS-CoV).Inactivated SARS-CoV has been explored as a vaccine against SARS-CoV.However,safe and potent adjuvants,especially with more efficient and economical needle-free vaccination are always needed more urgently in a pandemic.The development of a safe and effective mucosal adjuvant and vaccine for prevention of emergent infectious diseases such as SARS will be an important advancement.PIKA,a stabilized derivative of Poly(I:C),was previously reported to be safe and potent as adjuvant in mouse models.In the present study,we demonstrated that the intraperitoneal and intranasal co-administration of inactivated SARS-CoV vaccine together with this improved Poly(I:C)derivative induced strong anti-SARS-CoV mucosal and systemic humoral immune responses with neutralizing activity against pseudotyped virus.Although intraperitoneal immunization of inactivated SARS-CoV vaccine alone could induce a certain level of neutralizing activity in serum as well as in mucosal sites,co-administration of inactivated SARS-CoV vaccine with PIKA as adjuvant could induce a much higher neutralizing activity.When intranasal immunization was used,PIKA was obligatorily for inducing neutralizing activity in serum as well as in mucosal sites and was correlated with both mucosal IgA and mucosal IgG response.Overall,PIKA could be a good mucosal adjuvant candidate for inactivated SARS-CoV vaccine for use in possible future pandemic.

  9. How Irreversible Heat Transport Processes Drive Earth's Interdependent Thermal, Structural, and Chemical Evolution Providing a Strongly Heterogeneous, Layered Mantle

    Science.gov (United States)

    Hofmeister, A.; Criss, R. E.

    2013-12-01

    Because magmatism conveys radioactive isotopes plus latent heat rapidly upwards while advecting heat, this process links and controls the thermal and chemical evolution of Earth. We present evidence that the lower mantle-upper mantle boundary is a profound chemical discontinuity, leading to observed heterogeneities in the outermost layers that can be directly sampled, and construct an alternative view of Earth's internal workings. Earth's beginning involved cooling via explosive outgassing of substantial ice (mainly CO) buried with dust during accretion. High carbon content is expected from Solar abundances and ice in comets. Reaction of CO with metal provided a carbide-rich core while converting MgSiO3 to olivine via oxidizing reactions. Because thermodynamic law (and buoyancy of hot particles) indicates that primordial heat from gravitational segregation is neither large nor carried downwards, whereas differentiation forced radioactive elements upwards, formation of the core and lower mantle greatly cooled the Earth. Reference conductive geotherms, calculated using accurate and new thermal diffusivity data, require that heat-producing elements are sequestered above 670 km which limits convection to the upper mantle. These irreversible beginnings limit secular cooling to radioactive wind-down, permiting deduction of Earth's inventory of heat-producing elements from today's heat flux. Coupling our estimate for heat producing elements with meteoritic data indicates that Earth's oxide content has been underestimated. Density sorting segregated a Si-rich, peridotitic upper mantle from a refractory, oxide lower mantle with high Ca, Al and Ti contents, consistent with diamond inclusion mineralogy. Early and rapid differentiation means that internal temperatures have long been buffered by freezing of the inner core, allowing survival of crust as old as ca.4 Ga. Magmatism remains important. Melt escaping though stress-induced fractures in the rigid lithosphere imparts a

  10. Implications of partially degenerate neutrinos at a high scale in the light of KamLAND and WMAP

    CERN Document Server

    Joshipura, A S; Joshipura, Anjan S.; Mohanty, Subhendra

    2003-01-01

    Electroweak radiative corrections can generate the neutrino (mass)$^2$ difference required for the large mixing angle solution (LMA) to the solar neutrino problem if two of the neutrinos are assumed degenerate at high energy. We test this possibility with the existing experimental knowledge of the low energy neutrino mass and mixing parameters. We derive restrictions on ranges of the high scale mixing matrix elements and obtain predictions for the low energy parameters required in order to get the LMA solution of the solar neutrino problem picked out by KamLAND. We find that in the case of standard model this is achieved only when the (degenerate) neutrino masses lie in the range $(0.7-2) \\eV$ which is at odds with the cosmological limit $m_{\

  11. The transposon-like Correia elements encode numerous strong promoters and provide a potential new mechanism for phase variation in the meningococcus.

    Science.gov (United States)

    Siddique, Azeem; Buisine, Nicolas; Chalmers, Ronald

    2011-01-20

    Neisseria meningitidis is the primary causative agent of bacterial meningitis. The genome is rich in repetitive DNA and almost 2% is occupied by a diminutive transposon called the Correia element. Here we report a bioinformatic analysis defining eight subtypes of the element with four distinct types of ends. Transcriptional analysis, using PCR and a lacZ reporter system, revealed that two ends in particular encode strong promoters. The activity of the strongest promoter is dictated by a recurrent polymorphism (Y128) at the right end of the element. We highlight examples of elements that appear to drive transcription of adjacent genes and others that may express small non-coding RNAs. Pair-wise comparisons between three meningococcal genomes revealed that no more than two-thirds of Correia elements maintain their subtype at any particular locus. This is due to recombinational class switching between elements in a single strain. Upon switching subtype, a new allele is available to spread through the population by natural transformation. This process may represent a hitherto unrecognized mechanism for phase variation in the meningococcus. We conclude that the strain-to-strain variability of the Correia elements, and the large number of strong promoters encoded by them, allows for potentially widespread effects within the population as a whole. By defining the strength of the promoters encoded by the eight subtypes of Correia ends, we provide a resource that allows the transcriptional effects of a particular subtype at a given locus to be predicted.

  12. Heritability and coefficient of genetic variation analyses of phenotypic traits provide strong basis for high-resolution QTL mapping in the Collaborative Cross mouse genetic reference population.

    Science.gov (United States)

    Iraqi, Fuad A; Athamni, Hanifa; Dorman, Alexandra; Salymah, Yasser; Tomlinson, Ian; Nashif, Aysar; Shusterman, Ariel; Weiss, Ervin; Houri-Haddad, Yael; Mott, Richard; Soller, Morris

    2014-04-01

    Most biological traits of human importance are complex in nature; their manifestation controlled by the cumulative effect of many genetic factors interacting with one another and with the individual's life history. Because of this, mouse genetic reference populations (GRPs) consisting of collections of inbred lines or recombinant inbred lines (RIL) derived from crosses between inbred lines are of particular value in analysis of complex traits, since massive amounts of data can be accumulated on the individual lines. However, existing mouse GRPs are derived from inbred lines that share a common history, resulting in limited genetic diversity, and reduced mapping precision due to long-range gametic disequilibrium. To overcome these limitations, the Collaborative Cross (CC) a genetically highly diverse collection of mouse RIL was established. The CC, now in advanced stages of development, will eventually consist of about 500 RIL derived from reciprocal crosses of eight divergent founder strains of mice, including three wild subspecies. Previous studies have shown that the CC indeed contains enormous diversity at the DNA level, that founder haplotypes are inherited in expected frequency, and that long-range gametic disequilibrium is not present. We here present data, primarily from our own laboratory, documenting extensive genetic variation among CC lines as expressed in broad-sense heritability (H(2)) and by the well-known "coefficient of genetic variation," demonstrating the ability of the CC resource to provide unprecedented mapping precision leading to identification of strong candidate genes.

  13. Strong decoherence

    CERN Document Server

    Gell-Mann, Murray; Gell-Mann, Murray; Hartle, James B

    1997-01-01

    We introduce a condition for the strong decoherence of a set of alternative histories of a closed quantum-mechanical system such as the universe. The condition applies, for a pure initial state, to sets of homogeneous histories that are chains of projections, generally branch-dependent. Strong decoherence implies the consistency of probability sum rules but not every set of consistent or even medium decoherent histories is strongly decoherent. Two conditions characterize a strongly decoherent set of histories: (1) At any time the operators that effectively commute with generalized records of history up to that moment provide the pool from which --- with suitable adjustment for elapsed time --- the chains of projections extending history to the future may be drawn. (2) Under the adjustment process, generalized record operators acting on the initial state of the universe are approximately unchanged. This expresses the permanence of generalized records. The strong decoherence conditions (1) and (2) guarantee wha...

  14. Be7 solar neutrino measurement with KamLAND

    Energy Technology Data Exchange (ETDEWEB)

    Gando, A.; Gando, Y.; Hanakago, H.; Ikeda, H.; Inoue, K.; Ishidoshiro, K.; Ishikawa, H.; Kishimoto, Y.; Koga, M.; Matsuda, R.; Matsuda, S.; Mitsui, T.; Motoki, D.; Nakajima, K.; Nakamura, K.; Obata, A.; Oki, A.; Oki, Y.; Otani, M.; Shimizu, I.; Shirai, J.; Suzuki, A.; Tamae, K.; Ueshima, K.; Watanabe, H.; Xu, B. D.; Yamada, S.; Yamauchi, Y.; Yoshida, H.; Kozlov, A.; Takemoto, Y.; Yoshida, S.; Grant, C.; Keefer, G.; McKee, D. W.; Piepke, A.; Banks, T. I.; Bloxham, T.; Freedman, S. J.; Fujikawa, B. K.; Han, K.; Hsu, L.; Ichimura, K.; Murayama, H.; O' Donnell, T.; Steiner, H. M.; Winslow, L. A.; Dwyer, D.; Mauger, C.; McKeown, R. D.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Learned, J. G.; Sakai, M.; Horton-Smith, G. A.; Tang, A.; Downum, K. E.; Tolich, K.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Detwiler, J. A.; Enomoto, S.; Heeger, K.; Decowski, M. P.

    2015-11-30

    We report a measurement of the neutrino-electron elastic scattering rate of 862 keV 7Be solar neutrinos based on a 165.4 kt d exposure of KamLAND. The observed rate is 582±94(kt d)₋1, which corresponds to an 862-keV 7Be solar neutrino flux of (3.26±0.52)×109cm₋2s₋1, assuming a pure electron-flavor flux. Comparing this flux with the standard solar model prediction and further assuming three-flavor mixing, a νe survival probability of 0.66±0.15 is determined from the KamLAND data. Lastly, utilizing a global three-flavor oscillation analysis, we obtain a total 7Be solar neutrino flux of (5.82±1.02)×109cm₋2s₋1, which is consistent with the standard solar model predictions.

  15. Mixing Strong and Weak Targets Provides No Evidence against the Unequal-Variance Explanation of zRoc Slope: A Comment on Koen and Yonelinas (2010)

    Science.gov (United States)

    Starns, Jeffrey J.; Rotello, Caren M.; Ratcliff, Roger

    2012-01-01

    Koen and Yonelinas (2010; K&Y) reported that mixing classes of targets that had short (weak) or long (strong) study times had no impact on zROC slope, contradicting the predictions of the encoding variability hypothesis. We show that they actually derived their predictions from a mixture unequal-variance signal detection (UVSD) model, which…

  16. Constraints on flavor-dependent long range forces from solar neutrinos and KamLAND

    CERN Document Server

    Bandyopadhyay, A; Joshipura, A S; Bandyopadhyay, Abhijit; Dighe, Amol; Joshipura, Anjan S.

    2006-01-01

    Flavor-dependent long range (LR) leptonic forces, like those mediated by the $L_e-L_\\mu$ or $L_e -L_\\tau$ gauge bosons, constitute a minimal extension of the standard model that preserves its renormalizability. We study the impact of such interactions on the solar neutrino oscillations when the interaction range $R_{LR}$ is much larger than the Earth-Sun distance. The LR potential can dominate over the standard charged current potential inside the Sun in spite of strong constraints on the coupling $\\alpha$ of the LR force coming from the atmospheric neutrino data and laboratory search for new forces. We demonstrate that the solar and atmospheric neutrino mass scales do not get trivially decoupled even if $\\theta_{13}$ is vanishingly small. In addition, for $\\alpha \\gsim 10^{-52}$ and normal hierarchy, resonant enhancement of $\\theta_{13}$ results in nontrivial energy dependent effects on the $\

  17. Care coordination between specialty care and primary care: a focus group study of provider perspectives on strong practices and improvement opportunities

    Directory of Open Access Journals (Sweden)

    Kim B

    2015-01-01

    Full Text Available Bo Kim,1,2 Michelle A Lucatorto,3 Kara Hawthorne,4 Janis Hersh,5 Raquel Myers,6 A Rani Elwy,1,7 Glenn D Graham81Center for Healthcare Organization and Implementation Research, Edith Nourse Rogers Memorial VA Hospital, Bedford, 2Department of Psychiatry, Harvard Medical School, Boston, MA, 3Office of Nursing Services, Department of Veterans Affairs, 4Chief Business Office, Purchased Care, Washington, DC, 5New England Veterans Engineering Resource Center, Boston, MA, 6SJ Quinney College of Law, University of Utah, Salt Lake City, UT, 7Department of Health Policy and Management, Boston University School of Public Health, Boston, MA, 8Specialty Care Services (10P4E, Department of Veterans Affairs, Washington, DC, USAAbstract: Care coordination between the specialty care provider (SCP and the primary care provider (PCP is a critical component of safe, efficient, and patient-centered care. Veterans Health Administration conducted a series of focus groups of providers, from specialty care and primary care clinics at VA Medical Centers nationally, to assess 1 what SCPs and PCPs perceive to be current practices that enable or hinder effective care coordination with one another and 2 how these perceptions differ between the two groups of providers. A qualitative thematic analysis of the gathered data validates previous studies that identify communication as being an important enabler of coordination, and uncovers relationship building between specialty care and primary care (particularly through both formal and informal relationship-building opportunities such as collaborative seminars and shared lunch space, respectively to be the most notable facilitator of effective communication between the two sides. Results from this study suggest concrete next steps that medical facilities can take to improve care coordination, using as their basis the mutual understanding and respect developed between SCPs and PCPs through relationship-building efforts

  18. Task I: Dark Matter Search Experiments with Cryogenic Detectors: CDMS-I and CDMS-II Task II: Experimental Study of Neutrino Properties: EXO and KamLAND

    Energy Technology Data Exchange (ETDEWEB)

    Cabrera, Blas [Stanford Univ., CA (United States); Gratta, Giorgio [Stanford Univ., CA (United States)

    2013-08-30

    design and optimize the analysis. Neutrino Physics – In the period of performance the neutrino group successfully completed the construction of EXO-200 and commissioned the detector. Science data taking started on Jun 1, 2011. With the discovery of the 2-neutrino double-beta decay in 136-Xe and the first measurement of the 0-neutrino mode resulting in the most stringent limit of Majorana masses, our group continues to be a leading innovator in the field of neutrino physics which is central to DOE-HEP Intensity Frontier program. The phenomenon of neutrino oscillations, in part elucidated by our earlier efforts with the Palo Verde and KamLAND experiments, provides the crucial information that neutrino masses are non-zero and, yet, it contains no information on the value of the neutrino mass scale. In recent times our group has therefore shifted its focus to a high sensitivity 0-neutrino double beta decay program, EXO. The 0-neutrino double beta decay provides the best chance of extending the sensitivity to the neutrino mass scale below 10 meV but, maybe more importantly, it tests the nature of the neutrino wave function, providing the most sensitive probe for Majorana particles and lepton number violation. The EXO program, formulated by our group several years ago, plans to use up to tonnes of the isotope 136-Xe to study the 0-neutrino double beta decay mode. The EXO-200 detector is the first step in this program and it represents the only large US-led and based experiment taking data. The EXO-200 isotope enrichment program broke new grounds for the enterprise of double beta decay. The detector design and material selection program paid off, resulting in a background that is among the very best in the field. The “first light" of EXO-200 was very exciting with the discovery -in the first month of data- of the rarest 2-neutrino double beta decay mode ever observed. The lower limit on the 0-neutrino double beta decay half-life, published in Phys. Rev. Lett. and based on

  19. Strong Force

    CERN Document Server

    Without the strong force, there could be no life. The carbon in living matter is synthesised in stars via the strong force. Lighter atomic nuclei become bound together in a process called nuclear fusion. A minor change in this interaction would make life impossible. As its name suggests, the strong force is the most powerful of the 4 forces, yet its sphere of influence is limited to within the atomic nucleus. Indeed it is the strong force that holds together the quarks inside the positively charged protons. Without this glue, the quarks would fly apart repulsed by electromagnetism. In fact, it is impossible to separate 2 quarks : so much energy is needed, that a second pair of quarks is produced. Text for the interactive: Can you pull apart the quarks inside a proton?

  20. <strong>Mini-project>

    DEFF Research Database (Denmark)

    Katajainen, Jyrki

    2008-01-01

    In this project the goal is to develop the safe * family of containers for the CPH STL. The containers to be developed should be safer and more reliable than any of the existing implementations. A special focus should be put on strong exception safety since none of the existing prototypes available...... at the CPH STL can give this guarantee for all operations. In spite of the safety requirements, the strict running-time requirements specified in the C++ standard, and additional requirements specified in the CPH STL design documents, must be fulfilled....

  1. KRAS mutation-positive bronchial surface epithelium (BSE)-type lung adenocarcinoma with strong expression of TTF-1: a case providing a further insight as for the role of TTF-1 in the oncogenesis.

    Science.gov (United States)

    Takanashi, Yusuke; Tajima, Shogo; Hayakawa, Takamitsu; Neyatani, Hiroshi; Funai, Kazuhito

    2015-01-01

    Bronchial surface epithelium (BSE)-type lung adenocarcinoma is a subtype of non-terminal respiratory unit (TRU)-type lung adenocarcinoma originating in the bronchial surface epithelium. However, there are few known cases of BSE-type adenocarcinoma with marked expression of thyroid transcription factor-1 (TTF-1). This paper describes a very rare case of KRAS mutation-positive BSE-type adenocarcinoma that exhibited strong expression of TTF-1 that was putatively involved in oncogenesis. An 84-year-old woman, a never smoker, was referred to our hospital because of an abnormal chest radiograph. Chest computed tomography (CT) showed a solid mass lesion, 15 mm × 10 mm, with a relatively smooth margin in the left upper lobe. The patient underwent partial resection of the left upper lobe for strongly suspected lung cancer with a clinical stage of cT1aN0M0. Histopathological findings showed continuous migration of papillary, hyperplastic, atypical columnar tumor cells originating from normal bronchial surface epithelium, leading to a diagnosis of BSE-type adenocarcinoma. TTF-1 was strongly expressed in almost 100% of the tumor cells, which tested positive for the KRAS mutation. TTF-1 has recently attracted attention as an oncogene, and it is purportedly involved in the carcinogenesis and survival of lung adenocarcinoma cells. There is typically an inverse correlation between the respective expressions of KRAS and TTF-1, but in the present study, they appeared simultaneously and were both putatively involved as oncogenic driver alterations. This case is important in that it sheds some light on the largely unknown pathogenic mechanism of BSE-type adenocarcinoma.

  2. Strong Cosmic Censorship

    Science.gov (United States)

    Isenberg, James

    2017-01-01

    The Hawking-Penrose theorems tell us that solutions of Einstein's equations are generally singular, in the sense of the incompleteness of causal geodesics (the paths of physical observers). These singularities might be marked by the blowup of curvature and therefore crushing tidal forces, or by the breakdown of physical determinism. Penrose has conjectured (in his `Strong Cosmic Censorship Conjecture`) that it is generically unbounded curvature that causes singularities, rather than causal breakdown. The verification that ``AVTD behavior'' (marked by the domination of time derivatives over space derivatives) is generically present in a family of solutions has proven to be a useful tool for studying model versions of Strong Cosmic Censorship in that family. I discuss some of the history of Strong Cosmic Censorship, and then discuss what is known about AVTD behavior and Strong Cosmic Censorship in families of solutions defined by varying degrees of isometry, and discuss recent results which we believe will extend this knowledge and provide new support for Strong Cosmic Censorship. I also comment on some of the recent work on ``Weak Null Singularities'', and how this relates to Strong Cosmic Censorship.

  3. Strongly interacting Fermi gases

    Directory of Open Access Journals (Sweden)

    Bakr W.

    2013-08-01

    Full Text Available Strongly interacting gases of ultracold fermions have become an amazingly rich test-bed for many-body theories of fermionic matter. Here we present our recent experiments on these systems. Firstly, we discuss high-precision measurements on the thermodynamics of a strongly interacting Fermi gas across the superfluid transition. The onset of superfluidity is directly observed in the compressibility, the chemical potential, the entropy, and the heat capacity. Our measurements provide benchmarks for current many-body theories on strongly interacting fermions. Secondly, we have studied the evolution of fermion pairing from three to two dimensions in these gases, relating to the physics of layered superconductors. In the presence of p-wave interactions, Fermi gases are predicted to display toplogical superfluidity carrying Majorana edge states. Two possible avenues in this direction are discussed, our creation and direct observation of spin-orbit coupling in Fermi gases and the creation of fermionic molecules of 23Na 40K that will feature strong dipolar interactions in their absolute ground state.

  4. Building a Strong Foundation: Apprenticeships Provide Earning, Learning Opportunities

    Science.gov (United States)

    Finkel, Ed

    2016-01-01

    Partnerships between community colleges and employers to create apprenticeships have been around for decades. These traditionally have covered fields like the building trades--electrical, construction and others--as well as heavy manufacturing like the automobile industry. Inspired partly by a new federal apprenticeship consortium--and $175…

  5. Medicare Provider Data - Hospice Providers

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Hospice Utilization and Payment Public Use File provides information on services provided to Medicare beneficiaries by hospice providers. The Hospice PUF...

  6. Strong vector valued integrals

    CERN Document Server

    Beckmann, Ralf

    2011-01-01

    Strong Bochner type integrals with values in locally convex spaces are introduced. It is shown that the strong integral exists in the same cases as the weak (Gelfand-Pettis) integral is known to exist. The strong integral has better continuity properties that the weak integral.

  7. Maximum Genus of Strong Embeddings

    Institute of Scientific and Technical Information of China (English)

    Er-ling Wei; Yan-pei Liu; Han Ren

    2003-01-01

    The strong embedding conjecture states that any 2-connected graph has a strong embedding on some surface. It implies the circuit double cover conjecture: Any 2-connected graph has a circuit double cover.Conversely, it is not true. But for a 3-regular graph, the two conjectures are equivalent. In this paper, a characterization of graphs having a strong embedding with exactly 3 faces, which is the strong embedding of maximum genus, is given. In addition, some graphs with the property are provided. More generally, an upper bound of the maximum genus of strong embeddings of a graph is presented too. Lastly, it is shown that the interpolation theorem is true to planar Halin graph.

  8. Strongly Gorenstein Flat Dimensions

    Institute of Scientific and Technical Information of China (English)

    Chun Xia ZHANG; Li Min WANG

    2011-01-01

    This article is concerned with the strongly Gorenstein flat dimensions of modules and rings.We show this dimension has nice properties when the ring is coherent,and extend the well-known Hilbert's syzygy theorem to the strongly Gorenstein flat dimensions of rings.Also,we investigate the strongly Gorenstein flat dimensions of direct products of rings and (almost)excellent extensions of rings.

  9. <strong>Project proposal:strong>

    DEFF Research Database (Denmark)

    Katajainen, Jyrki

    2007-01-01

    The Standard Template Library (STL) is a collection of generic algorithms and data structures that is part of the standard run-time environment of the C++ programming language. The STL provides four kinds of associative element containers: set, multiset, map, and multimap. In this project the goal...

  10. <strong>Project proposal:strong>

    DEFF Research Database (Denmark)

    Katajainen, Jyrki

    2007-01-01

    The Standard Template Library (STL) is a collection of generic algorithms and data structures that is part of the standard run-time environment of the C++ programming language. The STL provides four kinds of associative element containers: set, multiset, map, and multimap. In this project the goal...

  11. Strong Field, Noncommutative QED

    Directory of Open Access Journals (Sweden)

    Anton Ilderton

    2010-05-01

    Full Text Available We review the effects of strong background fields in noncommutative QED. Beginning with the noncommutative Maxwell and Dirac equations, we describe how combined noncommutative and strong field effects modify the propagation of fermions and photons. We extend these studies beyond the case of constant backgrounds by giving a new and revealing interpretation of the photon dispersion relation. Considering scattering in background fields, we then show that the noncommutative photon is primarily responsible for generating deviations from strong field QED results. Finally, we propose a new method for constructing gauge invariant variables in noncommutative QED, and use it to analyse the physics of our null background fields.

  12. How strong is the strong interaction?

    Energy Technology Data Exchange (ETDEWEB)

    Blomgren, J.; Bergenwall, B.; Hildebrand, A.; Johansson, C.; Klug, J.; Mermod, P.; Nilsson, L.; Pomp, S.; Oesterlund, M. [Dept. of Neutron Research, Uppsala Univ., Uppsala (Sweden); Tippawan, U. [Dept. of Neutron Research, Uppsala Univ., Uppsala (Sweden)]|[Fast Neutron Research Facility, Dept. of Physics, Chiang Mai Univ. (Thailand); Jonsson, O.; Prokofiev, A.V. [The Svedberg Lab., Uppsala Univ., Uppsala (Sweden); Nadel-Turonski, P. [Dept. of Radiation Sciences, Uppsala Univ., Uppsala (Sweden); Olsson, N. [Dept. of Neutron Research, Uppsala Univ., Uppsala (Sweden)]|[Swedish Defence Research Agency, Stockholm (Sweden); Dangtip, S. [Fast Neutron Research Facility, Dept. of Physics, Chiang Mai Univ. (Thailand)

    2003-07-01

    Elastic neutron scattering plays a key role in establishing the neutron-nucleus potential, i.e., the interaction strength between a neutron and a nucleus. In ADS applications, this information is useful in many different ways. Elastic scattering data are needed when determining the neutron intensity profile in and ADS system. In addition, the optical potentials derived from elastic neutron scattering data are used as input in every model calculation with a neutron in the incident or exit channel. Recently, there has been intense international debate on the neutron-proton scattering cross section. In the global data base, the backward cross section differs by 10% or even more at energies above 100 MeV. It is difficult to overemphasize the importance of this issue. The np scattering cross section is used as cross section reference in essentially all measurements of neutron-induced cross sections. Thus, for many applied cross sections the absolute scale is uncertain by the same amount. Moreover, the np scattering cross section has been used to derive the pion-nucleon coupling constant, i.e., the absolute strength of the strong interaction. It is annoying to have such a large uncertainty for such a fundamental parameter. We are presenting new data on elastic neutron scattering at 96 MeV from {sup 12}C and {sup 208}Pb, where the latter is part of the HINDAS project. In addition, new data on np scattering at 190 MeV will be presented. The impact on ADS and fundamental physics will be discussed. (orig.)

  13. <strong>Project proposalstrong>

    DEFF Research Database (Denmark)

    Katajainen, Jyrki

    2005-01-01

    The Standard Template Library (STL) is a library of generic algorithms and data structures that has been incorporated in the C++ standard and ships with all modern C++ compilers. In the CPH STL project the goal is to implement an enhanced edition of the STL. The priority-queue class of the STL...... graph-theoretic or geometric problems. In this project, the goal is to implement a CPH STL extension of the priority-queue class which provides, in addition to the normal priority-queue functionality, the operations delete(), increase(), and meld(). To make the first two of these operations possible...

  14. The SNAP Strong Lens Survey

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, P.

    2005-01-03

    Basic considerations of lens detection and identification indicate that a wide field survey of the types planned for weak lensing and Type Ia SNe with SNAP are close to optimal for the optical detection of strong lenses. Such a ''piggy-back'' survey might be expected even pessimistically to provide a catalogue of a few thousand new strong lenses, with the numbers dominated by systems of faint blue galaxies lensed by foreground ellipticals. After sketching out our strategy for detecting and measuring these galaxy lenses using the SNAP images, we discuss some of the scientific applications of such a large sample of gravitational lenses: in particular we comment on the partition of information between lens structure, the source population properties and cosmology. Understanding this partitioning is key to assessing strong lens cosmography's value as a cosmological probe.

  15. Strongly interacting ultracold polar molecules

    CERN Document Server

    Gadway, Bryce

    2016-01-01

    This paper reviews recent advances in the study of strongly interacting systems of dipolar molecules. Heteronuclear molecules feature large and tunable electric dipole moments, which give rise to long-range and anisotropic dipole-dipole interactions. Ultracold samples of dipolar molecules with long-range interactions offer a unique platform for quantum simulations and the study of correlated many-body physics. We provide an introduction to the physics of dipolar quantum gases, both electric and magnetic, and summarize the multipronged efforts to bring dipolar molecules into the quantum regime. We discuss in detail the recent experimental progress in realizing and studying strongly interacting systems of polar molecules trapped in optical lattices, with particular emphasis on the study of interacting spin systems and non-equilibrium quantum magnetism. Finally, we conclude with a brief discussion of the future prospects for studies of strongly interacting dipolar molecules.

  16. Strongly correlated Bose gases

    Science.gov (United States)

    Chevy, F.; Salomon, C.

    2016-10-01

    The strongly interacting Bose gas is one of the most fundamental paradigms of quantum many-body physics and the subject of many experimental and theoretical investigations. We review recent progress on strongly correlated Bose gases, starting with a description of beyond mean-field corrections. We show that the Efimov effect leads to non universal phenomena and to a metastability of the low temperature Bose gas through three-body recombination to deeply bound molecular states. We outline differences and similarities with ultracold Fermi gases, discuss recent experiments on the unitary Bose gas, and finally present a few perspectives for future research.

  17. Abortion: Strong's counterexamples fail

    DEFF Research Database (Denmark)

    Di Nucci, Ezio

    2009-01-01

    This paper shows that the counterexamples proposed by Strong in 2008 in the Journal of Medical Ethics to Marquis's argument against abortion fail. Strong's basic idea is that there are cases--for example, terminally ill patients--where killing an adult human being is prima facie seriously morally......'s scenarios have some valuable future or admitted that killing them is not seriously morally wrong. Finally, if "valuable future" is interpreted as referring to objective standards, one ends up with implausible and unpalatable moral claims....

  18. Strong Little Magnets

    Science.gov (United States)

    Moloney, Michael J.

    2007-01-01

    Did you know that some strong little cylindrical magnets available in local hardware stores can have an effective circumferential current of 2500 A? This intriguing information can be obtained by hanging a pair of magnets at the center of a coil, as shown in Fig. 1, and measuring the oscillation frequency as a function of coil current.

  19. Flavour Democracy in Strong Unification

    CERN Document Server

    Abel, S A; Abel, Steven; King, Steven

    1998-01-01

    We show that the fermion mass spectrum may naturally be understood in terms of flavour democratic fixed points in supersymmetric theories which have a large domain of attraction in the presence of "strong unification". Our approach provides an alternative to the approximate Yukawa texture zeroes of the Froggatt-Nielsen mechanism. We discuss a particular model based on a broken gauged $SU(3)_L\\times SU(3)_R$ family symmetry which illustrates our approach.

  20. Strong Field Spherical Dynamos

    CERN Document Server

    Dormy, Emmanuel

    2014-01-01

    Numerical models of the geodynamo are usually classified in two categories: those denominated dipolar modes, observed when the inertial term is small enough, and multipolar fluctuating dynamos, for stronger forcing. I show that a third dynamo branch corresponding to a dominant force balance between the Coriolis force and the Lorentz force can be produced numerically. This force balance is usually referred to as the strong field limit. This solution co-exists with the often described viscous branch. Direct numerical simulations exhibit a transition from a weak-field dynamo branch, in which viscous effects set the dominant length scale, and the strong field branch in which viscous and inertial effects are largely negligible. These results indicate that a distinguished limit needs to be sought to produce numerical models relevant to the geodynamo and that the usual approach of minimizing the magnetic Prandtl number (ratio of the fluid kinematic viscosity to its magnetic diffusivity) at a given Ekman number is mi...

  1. Strongly Correlated Materials

    OpenAIRE

    Morosan, Emilia; Natelson, Douglas; Nevidomskyy, Andriy H.; Si, Qimiao

    2013-01-01

    Strongly correlated materials are profoundly affected by the repulsive electron-electron interaction. This stands in contrast to many commonly used materials such as silicon and aluminum, whose properties are comparatively unaffected by the Coulomb repulsion. Correlated materials often have remarkable properties and transitions between distinct, competing phases with dramatically different electronic and magnetic orders. These rich phenomena are fascinating from the basic science perspective ...

  2. Open Flavor Strong Decays

    Science.gov (United States)

    García-Tecocoatzi, H.; Bijker, R.; Ferretti, J.; Galatà, G.; Santopinto, E.

    2016-10-01

    In this contribution, we discuss the results of a QM calculation of the open-flavor strong decays of **** light nucleon resonances. These are the results of a recent calculation, where we used a modified ^3P_0 model for the amplitudes and the U(7) algebraic model and the hypercentral quark model to predict the baryon spectrum. The decay amplitudes are compared with the existing experimental data.

  3. Strongly Correlated Topological Insulators

    Science.gov (United States)

    2016-02-03

    Research Triangle Park , NC 27709-2211 Condensed Matter, Topological Phases of Matter REPORT DOCUMENTATION PAGE 11. SPONSOR/MONITOR’S REPORT NUMBER(S...Strongly Correlated Topological Insulators In the past year, the grant was used for work in the field of topological phases, with emphasis on finding...surface of topological insulators. In the past 3 years, we have started a new direction, that of fractional topological insulators. These are materials

  4. Strong Coupling and Classicalization

    CERN Document Server

    Dvali, Gia

    2016-01-01

    Classicalization is a phenomenon in which a theory prevents itself from entering into a strong-coupling regime, by redistributing the energy among many weakly-interacting soft quanta. In this way, the scattering process of some initial hard quanta splits into a large number of soft elementary processes. In short, the theory trades the strong coupling for a high-multiplicity of quanta. At very high energies, the outcome of such a scattering experiment is a production of soft states of high occupation number that are approximately classical. It is evident that black hole creation in particle collision at super-Planckian energies is a result of classicalization, but there is no a priory reason why this phenomenon must be limited to gravity. If the hierarchy problem is solved by classicalization, the LHC has a chance of detecting a tower of new resonances. The lowest-lying resonances must appear right at the strong coupling scale in form of short-lived elementary particles. The heavier members of the tower must b...

  5. Scalar strong interaction hadron theory

    CERN Document Server

    Hoh, Fang Chao

    2015-01-01

    The scalar strong interaction hadron theory, SSI, is a first principles' and nonlocal theory at quantum mechanical level that provides an alternative to low energy QCD and Higgs related part of the standard model. The quark-quark interaction is scalar rather than color-vectorial. A set of equations of motion for mesons and another set for baryons have been constructed. This book provides an account of the present state of a theory supposedly still at its early stage of development. This work will facilitate researchers interested in entering into this field and serve as a basis for possible future development of this theory.

  6. A STRONG LINK

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Trade frictions should not affect the mainstream of Sino-U.S. mutually beneficial economic and trade cooperation China and the United States have a complicated relationship, one that can be called a competitive partnership. The U.S. trade deficit with China, its third largest trading partner, hit a staggering $201.6 billion last year, an imbalance that is a major bone of contention. Yet, while frictions over trade, intellectual property rights and other issues grab the headlines, there is strong-and grow...

  7. Strongly correlated materials.

    Science.gov (United States)

    Morosan, Emilia; Natelson, Douglas; Nevidomskyy, Andriy H; Si, Qimiao

    2012-09-18

    Strongly correlated materials are profoundly affected by the repulsive electron-electron interaction. This stands in contrast to many commonly used materials such as silicon and aluminum, whose properties are comparatively unaffected by the Coulomb repulsion. Correlated materials often have remarkable properties and transitions between distinct, competing phases with dramatically different electronic and magnetic orders. These rich phenomena are fascinating from the basic science perspective and offer possibilities for technological applications. This article looks at these materials through the lens of research performed at Rice University. Topics examined include: Quantum phase transitions and quantum criticality in "heavy fermion" materials and the iron pnictide high temperature superconductors; computational ab initio methods to examine strongly correlated materials and their interface with analytical theory techniques; layered dichalcogenides as example correlated materials with rich phases (charge density waves, superconductivity, hard ferromagnetism) that may be tuned by composition, pressure, and magnetic field; and nanostructure methods applied to the correlated oxides VO₂ and Fe₃O₄, where metal-insulator transitions can be manipulated by doping at the nanoscale or driving the system out of equilibrium. We conclude with a discussion of the exciting prospects for this class of materials.

  8. Strong Coupling Holography

    CERN Document Server

    Dvali, Gia

    2009-01-01

    We show that whenever a 4-dimensional theory with N particle species emerges as a consistent low energy description of a 3-brane embedded in an asymptotically-flat (4+d)-dimensional space, the holographic scale of high-dimensional gravity sets the strong coupling scale of the 4D theory. This connection persists in the limit in which gravity can be consistently decoupled. We demonstrate this effect for orbifold planes, as well as for the solitonic branes and string theoretic D-branes. In all cases the emergence of a 4D strong coupling scale from bulk holography is a persistent phenomenon. The effect turns out to be insensitive even to such extreme deformations of the brane action that seemingly shield 4D theory from the bulk gravity effects. A well understood example of such deformation is given by large 4D Einstein term in the 3-brane action, which is known to suppress the strength of 5D gravity at short distances and change the 5D Newton's law into the four-dimensional one. Nevertheless, we observe that the ...

  9. Strongly nonlinear oscillators analytical solutions

    CERN Document Server

    Cveticanin, Livija

    2014-01-01

    This book provides the presentation of the motion of pure nonlinear oscillatory systems and various solution procedures which give the approximate solutions of the strong nonlinear oscillator equations. The book presents the original author’s method for the analytical solution procedure of the pure nonlinear oscillator system. After an introduction, the physical explanation of the pure nonlinearity and of the pure nonlinear oscillator is given. The analytical solution for free and forced vibrations of the one-degree-of-freedom strong nonlinear system with constant and time variable parameter is considered. Special attention is given to the one and two mass oscillatory systems with two-degrees-of-freedom. The criteria for the deterministic chaos in ideal and non-ideal pure nonlinear oscillators are derived analytically. The method for suppressing chaos is developed. Important problems are discussed in didactic exercises. The book is self-consistent and suitable as a textbook for students and also for profess...

  10. PREFACE: Strongly Coupled Coulomb Systems Strongly Coupled Coulomb Systems

    Science.gov (United States)

    Neilson, David; Senatore, Gaetano

    2009-05-01

    This special issue contains papers presented at the International Conference on Strongly Coupled Coulomb Systems (SCCS), held from 29 July-2 August 2008 at the University of Camerino. Camerino is an ancient hill-top town located in the Apennine mountains of Italy, 200 kilometres northeast of Rome, with a university dating back to 1336. The Camerino conference was the 11th in a series which started in 1977: 1977: Orleans-la-Source, France, as a NATO Advanced Study Institute on Strongly Coupled Plasmas (hosted by Marc Feix and Gabor J Kalman) 1982: Les Houches, France (hosted by Marc Baus and Jean-Pierre Hansen) 1986: Santa Cruz, California, USA (hosted by Forrest J Rogers and Hugh E DeWitt) 1989: Tokyo, Japan (hosted by Setsuo Ichimaru) 1992: Rochester, New York, USA (hosted by Hugh M Van Horn and Setsuo Ichimaru) 1995: Binz, Germany (hosted by Wolf Dietrich Kraeft and Manfred Schlanges) 1997: Boston, Massachusetts, USA (hosted by Gabor J Kalman) 1999: St Malo, France (hosted by Claude Deutsch and Bernard Jancovici) 2002: Santa Fe, New Mexico, USA (hosted by John F Benage and Michael S Murillo) 2005: Moscow, Russia (hosted by Vladimir E Fortov and Vladimir Vorob'ev). The name of the series was changed in 1996 from Strongly Coupled Plasmas to Strongly Coupled Coulomb Systems to reflect a wider range of topics. 'Strongly Coupled Coulomb Systems' encompasses diverse many-body systems and physical conditions. The purpose of the conferences is to provide a regular international forum for the presentation and discussion of research achievements and ideas relating to a variety of plasma, liquid and condensed matter systems that are dominated by strong Coulomb interactions between their constituents. Each meeting has seen an evolution of topics and emphases that have followed new discoveries and new techniques. The field has continued to see new experimental tools and access to new strongly coupled conditions, most recently in the areas of warm matter, dusty plasmas

  11. Strongly Coupled Cosmologies

    CERN Document Server

    Bonometto, S A; Musco, I; Mainini, R; Maccio', A V

    2014-01-01

    Models including an energy transfer from CDM to DE are widely considered in the literature, namely to allow DE a significant high-z density. Strongly Coupled cosmologies assume a much larger coupling between DE and CDM, together with the presence of an uncoupled warm DM component, as the role of CDM is mostly restricted to radiative eras. This allows us to preserve small scale fluctuations even if the warm particle, possibly a sterile neutrino, is quite light, O(100 eV). Linear theory and numerical simulations show that these cosmologies agree with LCDM on supergalactic scales; e.g., CMB spectra are substantially identical. Simultaneously, simulations show that they significantly ease problems related to the properties of MW satellites and cores in dwarfs. SC cosmologies also open new perspectives on early black hole formation, and possibly lead towards unificating DE and inflationary scalar fields.

  12. On Strong Cosmic Censorship

    CERN Document Server

    Isenberg, James

    2015-01-01

    For almost half of the one hundred year history of Einstein's theory of general relativity, Strong Cosmic Censorship has been one of its most intriguing conjectures. The SCC conjecture addresses the issue of the nature of the singularities found in most solutions of Einstein's gravitational field equations: Are such singularities generically characterized by unbounded curvature? Is the existence of a Cauchy horizon (and the accompanying extensions into spacetime regions in which determinism fails) an unstable feature of solutions of Einstein's equations? In this short review article, after briefly commenting on the history of the SCC conjecture, we survey some of the progress made in research directed either toward supporting SCC or toward uncovering some of its weaknesses. We focus in particular on model versions of SCC which have been proven for restricted families of spacetimes (e.g., the Gowdy spacetimes), and the role played by the generic presence of Asymptotically Velocity Term Dominated behavior in th...

  13. LIGO: The strong belief

    CERN Multimedia

    Antonella Del Rosso

    2016-01-01

    Twenty years of designing, building and testing a number of innovative technologies, with the strong belief that the endeavour would lead to a historic breakthrough. The Bulletin publishes an abstract of the Courier’s interview with Barry Barish, one of the founding fathers of LIGO.   The plots show the signals of gravitational waves detected by the twin LIGO observatories at Livingston, Louisiana, and Hanford, Washington. (Image: Caltech/MIT/LIGO Lab) On 11 February, the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo collaborations published a historic paper in which they showed a gravitational signal emitted by the merger of two black holes. These results come after 20 years of hard work by a large collaboration of scientists operating the two LIGO observatories in the US. Barry Barish, Linde Professor of Physics, Emeritus at the California Institute of Technology and former Director of the Global Design Effort for the Internat...

  14. Finding Strong Bridges and Strong Articulation Points in Linear Time

    Science.gov (United States)

    Italiano, Giuseppe F.; Laura, Luigi; Santaroni, Federico

    Given a directed graph G, an edge is a strong bridge if its removal increases the number of strongly connected components of G. Similarly, we say that a vertex is a strong articulation point if its removal increases the number of strongly connected components of G. In this paper, we present linear-time algorithms for computing all the strong bridges and all the strong articulation points of directed graphs, solving an open problem posed in [2].

  15. John Strong (1941 - 2006)

    CERN Multimedia

    Wickens, F

    Our friend and colleague John Strong was cruelly taken from us by a brain tumour on Monday 31st July, a few days before his 65th birthday John started his career working with a group from Westfield College, under the leadership of Ted Bellamy. He obtained his PhD and spent the early part of his career on experiments at Rutherford Appleton Laboratory (RAL), but after the early 1970s his research was focussed on experiments in CERN. Over the years he made a number of notable contributions to experiments in CERN: The Omega spectrometer adopted a system John had originally developed for experiments at RAL using vidicon cameras to record the sparks in the spark chambers; He contributed to the success of NA1 and NA7, where he became heavily involved in the electronic trigger systems; He was responsible for the second level trigger system for the ALEPH detector and spent five years leading a team that designed and built the system, which ran for twelve years with only minor interventions. Following ALEPH he tur...

  16. Foreshocks of strong earthquakes

    Science.gov (United States)

    Guglielmi, A. V.; Sobisevich, L. E.; Sobisevich, A. L.; Lavrov, I. P.

    2014-07-01

    The specific enhancement of ultra-low-frequency (ULF) electromagnetic oscillations a few hours prior to the strong earthquakes, which was previously mentioned in the literature, motivated us to search for the distinctive features of the mechanical (foreshock) activity of the Earth's crust in the epicentral zones of the future earthquakes. Activation of the foreshocks three hours before the main shock is revealed, which is roughly similar to the enhancement of the specific electromagnetic ULF emission. It is hypothesized that the round-the-world seismic echo signals from the earthquakes, which form the peak of energy release 2 h 50 min before the main events, act as the triggers of the main shocks due to the cumulative action of the surface waves converging to the epicenter. It is established that the frequency of the fluctuations in the foreshock activity decreases at the final stages of the preparation of the main shocks, which probably testifies to the so-called mode softening at the approach of the failure point according to the catastrophe theory.

  17. <strong>Anonysense>: privacy-aware people-centric sensingstrong>

    DEFF Research Database (Denmark)

    Triandopoulos, Nikolaos; Cornelius, Cory; Kapadia, Apu

    2008-01-01

    Personal mobile devices are increasingly equipped with the capability to sense the physical world (through cameras, microphones, and accelerometers, for example) and the, network world (with Wi-Fi and Bluetooth interfaces). Such devices offer many new opportunities for cooperative sensing...... of mobile systems: protecting the privacy of participants while allowing their devices to reliably contribute high-quality data to these large-scale applications. We describe AnonySense, a privacy-aware architecture for realizing pervasive applications based on collaborative, opportunistic sensing...... by personal mobile devices. AnonySense allows applications to submit sensing tasks that will be distributed across anonymous participating mobile devices, later receiving verified, yet anonymized, sensor data reports back from the field, thus providing the first secure implementation of this participatory...

  18. Strongly Interacting Planetary Systems

    Science.gov (United States)

    Ford, Eric

    2017-01-01

    Both ground-based Doppler surveys and NASA's Kepler mission have discovered a diversity of planetary system architectures that challenge theories of planet formation. Systems of tightly-packed or near-resonant planets are particularly useful for constraining theories of orbital migration and the excitation of orbital eccentricities and inclinations. In particular, transit timing variations (TTVs) provide a powerful tool to characterize the masses and orbits of dozens of small planets, including many planets at orbital periods beyond the reach of both current Doppler surveys and photoevaporation-induced atmospheric loss. Dynamical modeling of these systems has identified some ``supper-puffy'' planets, i.e., low mass planets with surprisingly large radii and low densities. I will describe a few particularly interesting planetary systems and discuss the implications for the formation of planets ranging from gaseous super-Earth-size planets to rocky planets the size of Mars.

  19. Strong embeddings of minimum genus

    CERN Document Server

    Mohar, Bojan

    2009-01-01

    A "folklore conjecture, probably due to Tutte" (as described in [P.D. Seymour, Sums of circuits, Graph theory and related topics (Proc. Conf., Univ. Waterloo, 1977), pp. 341-355, Academic Press, 1979]) asserts that every bridgeless cubic graph can be embedded on a surface of its own genus in such a way that the face boundaries are cycles of the graph. In this paper we consider closed 2-cell embeddings of graphs and show that certain (cubic) graphs (of any fixed genus) have closed 2-cell embedding only in surfaces whose genus is very large (proportional to the order of these graphs), thus providing plethora of strong counterexamples to the above conjecture. The main result yielding such counterexamples may be of independent interest.

  20. Strong convergence theorems for strongly relatively nonexpansive sequences and applications

    CERN Document Server

    Aoyama, Koji; Kohsaka, Fumiaki

    2012-01-01

    The aim of this paper is to establish strong convergence theorems for a strongly relatively nonexpansive sequence in a smooth and uniformly convex Banach space. Then we employ our results to approximate solutions of the zero point problem for a maximal monotone operator and the fixed point problem for a relatively nonexpansive mapping.

  1. Strongly Irreducible Submodules of Modules

    Institute of Scientific and Technical Information of China (English)

    A. KHAKSARI; M. ERSHAD; H. SHARIF

    2006-01-01

    Strongly irreducible submodules of modules are defined as follows: A submodule N of an R-module M is said to be strongly irreducible if for submodules L and K of M, the inclusion L ∩ K (∈) TV implies that either L (∈) N or K (∈) N. The relationship among the families of irreducible, strongly irreducible, prime and primary submodules of an .R-module M is considered, and a characterization of Noetherian modules which contain a non-prime strongly irreducible submodule is given.

  2. EDITORIAL: Strongly correlated electron systems Strongly correlated electron systems

    Science.gov (United States)

    Ronning, Filip; Batista, Cristian

    2011-03-01

    during SCES 2010. As we learned, past dogmas about strongly correlated materials and phenomena must be re-examined with an open and inquisitive mind. Invited speakers and respected leaders in the field were invited to contribute to this special issue and we have insisted that they present new data, ideas, or perspectives, as opposed to simply an overview of their past work. As with the conference, this special issue touches upon recent developments of strongly correlated electron systems in d-electron materials, such as Sr3Ru2O7, graphene, and the new Fe-based superconductors, but it is dominated by topics in f-electron compounds. Contributions reflect the growing appreciation for the influence of disorder and frustration, the need for organizing principles, as well as detailed investigations on particular materials of interest and, of course, new materials. As this special issue could not possibly capture the full breadth and depth that the conference had to offer, it is being published simultaneously with an issue of Journal of Physics: Conference Series containing 157 manuscripts in which all poster presenters at SCES 2010 were invited to contribute. Since this special issue grew out of the 2010 SCES conference, we take this opportunity to give thanks. This conference would not have been possible without the hard work of the SCES 2010 Program Committee, International and National Advisory Committees, Local Committee, and conference organizers, the New Mexico Consortium. We thank them as well as those organizations that generously provided financial support: ICAM-I2CAM, Quantum Design, Lakeshore, the National High Magnetic Field Laboratory and the Department of Energy National Laboratories at Argonne, Berkeley, Brookhaven, Los Alamos and Oak Ridge. Of course, we especially thank the participants for bringing new ideas and new results, without which SCES 2010 would not have been possible. Strongly correlated electron systems contents Spin-orbit coupling and k

  3. Finding quantum effects in strong classical potentials

    Science.gov (United States)

    Hegelich, B. Manuel; Labun, Lance; Labun, Ou Z.

    2017-06-01

    The long-standing challenge to describing charged particle dynamics in strong classical electromagnetic fields is how to incorporate classical radiation, classical radiation reaction and quantized photon emission into a consistent unified framework. The current, semiclassical methods to describe the dynamics of quantum particles in strong classical fields also provide the theoretical framework for fundamental questions in gravity and hadron-hadron collisions, including Hawking radiation, cosmological particle production and thermalization of particles created in heavy-ion collisions. However, as we show, these methods break down for highly relativistic particles propagating in strong fields. They must therefore be improved and adapted for the description of laser-plasma experiments that typically involve the acceleration of electrons. Theory developed from quantum electrodynamics, together with dedicated experimental efforts, offer the best controllable context to establish a robust, experimentally validated foundation for the fundamental theory of quantum effects in strong classical potentials.

  4. Short proofs of strong normalization

    OpenAIRE

    Wojdyga, Aleksander

    2008-01-01

    This paper presents simple, syntactic strong normalization proofs for the simply-typed lambda-calculus and the polymorphic lambda-calculus (system F) with the full set of logical connectives, and all the permutative reductions. The normalization proofs use translations of terms and types to systems, for which strong normalization property is known.

  5. Strongly Zero-Dimensional Locales

    Institute of Scientific and Technical Information of China (English)

    KOU Hui; LUO Mao Kang

    2002-01-01

    New kinds of strongly zero-dimensional locales are introduced and characterized, whichare different from Johnstone's, and almost all the topological properties for strongly zero-dimensionalspaces have the pointless localic forms. Particularly, the Stone-Cech compactification of a stronglyzero-dimensional locale is stongly zero-dimensional.

  6. About Strongly Universal Cellular Automata

    Directory of Open Access Journals (Sweden)

    Maurice Margenstern

    2013-09-01

    Full Text Available In this paper, we construct a strongly universal cellular automaton on the line with 11 states and the standard neighbourhood. We embed this construction into several tilings of the hyperbolic plane and of the hyperbolic 3D space giving rise to strongly universal cellular automata with 10 states.

  7. Patterns of Strong Coupling for LHC Searches

    CERN Document Server

    Liu, Da; Rattazzi, Riccardo; Riva, Francesco

    2016-11-23

    Even though the Standard Model (SM) is weakly coupled at the Fermi scale, a new strong dynamics involving its degrees of freedom may conceivably lurk at slightly higher energies, in the multi TeV range. Approximate symmetries provide a structurally robust context where, within the low energy description, the dimensionless SM couplings are weak, while the new strong dynamics manifests itself exclusively through higher-derivative interactions. We present an exhaustive classification of such scenarios in the form of effective field theories, paying special attention to new classes of models where the strong dynamics involves, along with the Higgs boson, the SM gauge bosons and/or the fermions. The IR softness of the new dynamics suppresses its effects at LEP energies, but deviations are in principle detectable at the LHC, even at energies below the threshold for production of new states. Our construction provides the so far unique structurally robust context where to motivate several searches in Higgs physics, d...

  8. Effects of strong disorder in strongly correlated superconductors

    Science.gov (United States)

    Chakraborty, Debmalya; Sensarma, Rajdeep; Ghosal, Amit

    2017-01-01

    We investigate the effect of strong disorder on a system with strong electronic repulsion. In the absence of disorder, the system has a d-wave superconducting ground state with strong non-BCS features due to its proximity to a Mott insulator. We find that while strong correlations make superconductivity in this system immune to weak disorder, superconductivity is destroyed efficiently when disorder strength is comparable to the effective bandwidth. The suppression of charge motion in regions of strong potential fluctuation leads to the formation of Mott insulating patches, which anchor a larger nonsuperconducting region around them. The system thus breaks into islands of Mott insulating and superconducting regions, with Anderson insulating regions occurring along the boundary of these regions. Thus, electronic correlation and disorder, when both are strong, aid each other in destroying superconductivity, in contrast to their competition at weak disorder. Our results shed light on why zinc impurities are efficient in destroying superconductivity in cuprates, even though it is robust to weaker impurities.

  9. New quarks: exotic versus strong

    OpenAIRE

    Holdom, B.

    2011-01-01

    The new quarks of a fourth family are being pushed into the strongly interacting regime due to the lower limits on their masses. The theoretical basis and experimental implications of such quarks are compared with exotic quarks.

  10. Cavity quantum electrodynamics: Beyond strong

    Science.gov (United States)

    Murch, Kater

    2017-01-01

    When light and matter are strongly coupled, they lose their distinct character and merge into a hybrid state. Three experiments explore this exotic regime using artificial atoms, with promise for quantum technologies.

  11. Strong nonlinear oscillators analytical solutions

    CERN Document Server

    Cveticanin, Livija

    2017-01-01

    This book outlines an analytical solution procedure of the pure nonlinear oscillator system, offering a solution for free and forced vibrations of the one-degree-of-freedom strong nonlinear system with constant and time variable parameter. Includes exercises.

  12. Creating and Nurturing Strong Teams.

    Science.gov (United States)

    Martin, Kaye M.

    1999-01-01

    Discusses ways to create and sustain strong teaching teams, including matching curriculum goals, complementary professional strengths, and exercise of autonomy. Elaborates the administrator's role in nurturing and supporting teamwork. (JPB)

  13. ClassSTRONG: Classical simulations of Strong Field processes

    CERN Document Server

    Ciappina, M F; Lewenstein, M

    2013-01-01

    A set of Mathematica functions is presented to model classically two of the most important processes in strong field physics, namely high-order harmonic generation (HHG) and above-threshold ionization (ATI). Our approach is based on the numerical solution of the Newton-Lorentz equation of an electron moving on an electric field and takes advantage of the symbolic languages features and graphical power of Mathematica. Similarly as in the Strong Field Approximation (SFA), the effects of atomic potential on the motion of electron in the laser field are neglected. The SFA has proven to be an essential tool in strong field physics in the sense that it is able to predict with great precision the harmonic (in the HHG) and energy (in the ATI) limits. We have extended substantially the conventional classical simulations, where the electric field is only dependent on time, including spatial nonhomogeneous fields and spatial and temporal synthesized fields. Spatial nonhomogeneous fields appear when metal nanosystems int...

  14. Patterns of strong coupling for LHC searches

    Science.gov (United States)

    Liu, Da; Pomarol, Alex; Rattazzi, Riccardo; Riva, Francesco

    2016-11-01

    Even though the Standard Model (SM) is weakly coupled at the Fermi scale, a new strong dynamics involving its degrees of freedom may conceivably lurk at slightly higher energies, in the multi TeV range. Approximate symmetries provide a structurally robust context where, within the low energy description, the dimensionless SM couplings are weak, while the new strong dynamics manifests itself exclusively through higher-derivative interactions. We present an exhaustive classification of such scenarios in the form of effective field theories, paying special attention to new classes of models where the strong dynamics involves, along with the Higgs boson, the SM gauge bosons and/or the fermions. The IR softness of the new dynamics suppresses its effects at LEP energies, but deviations are in principle detectable at the LHC, even at energies below the threshold for production of new states. We believe our construction provides the so far unique structurally robust context where to motivate several LHC searches in Higgs physics, diboson production, or W W scattering. Perhaps surprisingly, the interplay between weak coupling, strong coupling and derivatives, which is controlled by symmetries, can override the naive expansion in operator dimension, providing instances where dimension-8 dominates dimension-6, well within the domain of validity of the low energy effective theory. This result reveals the limitations of an analysis that is both ambitiously general and restricted to dimension-6 operators.

  15. Vacuum birefringence in strong inhomogeneous electromagnetic fields

    CERN Document Server

    Karbstein, Felix; Reuter, Maria; Zepf, Matt

    2015-01-01

    Birefringence is one of the fascinating properties of the vacuum of quantum electrodynamics (QED) in strong electromagnetic fields. The scattering of linearly polarized incident probe photons into a perpendicularly polarized mode provides a distinct signature of the optical activity of the quantum vacuum and thus offers an excellent opportunity for a precision test of non-linear QED. Precision tests require accurate predictions and thus a theoretical framework that is capable of taking the detailed experimental geometry into account. We derive analytical solutions for vacuum birefringence which include the spatio-temporal field structure of a strong optical pump laser field and an x-ray probe. We show that the angular distribution of the scattered photons depends strongly on the interaction geometry and find that scattering of the perpendicularly polarized scattered photons out of the cone of the incident probe x-ray beam is the key to making the phenomenon experimentally accessible with the current generatio...

  16. Institutionalizing Strong Sustainability: A Rawlsian Perspective

    Directory of Open Access Journals (Sweden)

    Konrad Ott

    2014-02-01

    Full Text Available The article aims to provide some ethical orientation on how sustainability might be actualized by institutions. Since institutionalization is about rules and organization, it presupposes ideas and concepts by which institutions can be substantiated. After outlining terminology, the article deals with underlying ethical and conceptual problems which are highly relevant for any suggestions concerning institutionalization. These problems are: (a the ethical scope of the sustainability perspective (natural capital, poverty, sentient animals, (b the theory of justice on which ideas about sustainability are built (capability approach, Rawlsianism, and (c the favored concept of sustainability (weak, intermediate, and strong sustainability. These problems are analyzed in turn. As a result, a Rawlsian concept of rule-based strong sustainability is proposed. The specific problems of institutionalization are addressed by applying Rawls’s concept of branches. The article concludes with arguments in favor of three transnational duties which hold for states that have adopted Rawlsian strong sustainability.

  17. Therapy Provider Phase Information

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Therapy Provider Phase Information dataset is a tool for providers to search by their National Provider Identifier (NPI) number to determine their phase for...

  18. Strong Photoassociation in Ultracold Fermions

    Science.gov (United States)

    Jing, Li; Jamison, Alan; Rvachov, Timur; Ebadi, Sepher; Son, Hyungmok; Jiang, Yijun; Zwierlein, Martin; Ketterle, Wolfgang

    2016-05-01

    Despite many studies there are still open questions about strong photoassociation in ultracold gases. Photoassociation occurs only at short range and thus can be used as a tool to probe and control the two-body correlation function in an interacting many-body system and to engineer Hamiltonians using dissipation. We propose the possibility to slow down decoherence by photoassociation through the quantum Zeno effect. This can realized by shining strong photoassociation light on the superposition of the lowest two hyperfine states of Lithium 6. NSF, ARO-MURI, Samsung, NSERC.

  19. Strong near-epoch dependence

    Institute of Scientific and Technical Information of China (English)

    LIN Zhengyan

    2004-01-01

    We introduce a new class of dependent sequences of random variables, which is a subclass of near-epoch dependent sequences, but can also be approximated by mixing sequences. For this kind of sequences of random variables, we call them strong nearepoch dependent sequences, a p-order, p > 2, (maximum) moment inequality is established under weaker dependence sizes.

  20. Strong decays of qqq baryons

    CERN Document Server

    Bijker, R; Leviatan, A

    1997-01-01

    We study strong decays of nonstrange baryons by making use of the algebraic approach to hadron structure. Within this framework we derive closed expressions for decay widths in an elementary-meson emission model and use these to analyze the experimental data for $N^* \\rightarrow N + \\pi$, $N^* + \\pi$, $\\Delta^* \\rightarrow \\Delta + \\pi$ and $\\Delta^* \\rightarrow \\Delta +

  1. Strong coupling electroweak symmetry breaking

    Energy Technology Data Exchange (ETDEWEB)

    Barklow, T.L. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Burdman, G. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Physics; Chivukula, R.S. [Boston Univ., MA (United States). Dept. of Physics

    1997-04-01

    The authors review models of electroweak symmetry breaking due to new strong interactions at the TeV energy scale and discuss the prospects for their experimental tests. They emphasize the direct observation of the new interactions through high-energy scattering of vector bosons. They also discuss indirect probes of the new interactions and exotic particles predicted by specific theoretical models.

  2. Strong metric dimension: A survey

    Directory of Open Access Journals (Sweden)

    Kratica Jozef

    2014-01-01

    Full Text Available The strong metric dimension has been a subject of considerable amount of research in recent years. This survey describes the related development by bringing together theoretical results and computational approaches, and places the recent results within their historical and scientific framework. [Projekat Ministarstva nauke Republike Srbije, br. 174010 i br. 174033

  3. Strong Decomposition of Random Variables

    DEFF Research Database (Denmark)

    Hoffmann-Jørgensen, Jørgen; Kagan, Abram M.; Pitt, Loren D.;

    2007-01-01

    A random variable X is stongly decomposable if X=Y+Z where Y=Φ(X) and Z=X-Φ(X) are independent non-degenerated random variables (called the components). It is shown that at least one of the components is singular, and we derive a necessary and sufficient condition for strong decomposability...... of a discrete random variable....

  4. Kinetic mixing at strong coupling

    Science.gov (United States)

    Del Zotto, Michele; Heckman, Jonathan J.; Kumar, Piyush; Malekian, Arada; Wecht, Brian

    2017-01-01

    A common feature of many string-motivated particle physics models is additional strongly coupled U (1 )'s. In such sectors, electric and magnetic states have comparable mass, and integrating out modes also charged under U (1 ) hypercharge generically yields C P preserving electric kinetic mixing and C P violating magnetic kinetic mixing terms. Even though these extra sectors are strongly coupled, we show that in the limit where the extra sector has approximate N =2 supersymmetry, we can use formal methods from Seiberg-Witten theory to compute these couplings. We also calculate various quantities of phenomenological interest such as the cross section for scattering between visible sector states and heavy extra sector states as well as the effects of supersymmetry breaking induced from coupling to the minimal supersymmetric Standard Model.

  5. Strongly correlated systems numerical methods

    CERN Document Server

    Mancini, Ferdinando

    2013-01-01

    This volume presents, for the very first time, an exhaustive collection of those modern numerical methods specifically tailored for the analysis of Strongly Correlated Systems. Many novel materials, with functional properties emerging from macroscopic quantum behaviors at the frontier of modern research in physics, chemistry and material science, belong to this class of systems. Any technique is presented in great detail by its own inventor or by one of the world-wide recognized main contributors. The exposition has a clear pedagogical cut and fully reports on the most relevant case study where the specific technique showed to be very successful in describing and enlightening the puzzling physics of a particular strongly correlated system. The book is intended for advanced graduate students and post-docs in the field as textbook and/or main reference, but also for other researchers in the field who appreciate consulting a single, but comprehensive, source or wishes to get acquainted, in a as painless as possi...

  6. Strongly correlated systems experimental techniques

    CERN Document Server

    Mancini, Ferdinando

    2015-01-01

    The continuous evolution and development of experimental techniques is at the basis of any fundamental achievement in modern physics. Strongly correlated systems (SCS), more than any other, need to be investigated through the greatest variety of experimental techniques in order to unveil and crosscheck the numerous and puzzling anomalous behaviors characterizing them. The study of SCS fostered the improvement of many old experimental techniques, but also the advent of many new ones just invented in order to analyze the complex behaviors of these systems. Many novel materials, with functional properties emerging from macroscopic quantum behaviors at the frontier of modern research in physics, chemistry and materials science, belong to this class of systems. The volume presents a representative collection of the modern experimental techniques specifically tailored for the analysis of strongly correlated systems. Any technique is presented in great detail by its own inventor or by one of the world-wide recognize...

  7. Numerical micromagnetism of strong inhomogeneities

    Energy Technology Data Exchange (ETDEWEB)

    Andreas, Christian [Peter Grünberg Institut (PGI-6), Forschungszentrum Jülich GmbH, D-52428 Jülich (Germany); Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504, Strasbourg (France); Gliga, Sebastian [Laboratory for Micro- and Nanotechnology, Paul Scherrer Institute, 5232 Villigen PSI (Switzerland); Laboratory for Mesoscopic Systems, Department of Materials, ETH Zurich, 8093 Zurich (Switzerland); Hertel, Riccardo, E-mail: hertel@ipcms.unistra.fr [Institut de Physique et Chimie des Matériaux de Strasbourg, Université de Strasbourg, CNRS UMR 7504, Strasbourg (France)

    2014-08-01

    The size of micromagnetic structures, such as domain walls or vortices, is comparable to the exchange length of the ferromagnet. Both, the exchange length of the stray field l{sub s} and the magnetocrystalline exchange length l{sub k}, are material-dependent quantities that usually lie in the nanometer range. This emphasizes the theoretical challenges associated with the mesoscopic nature of micromagnetism: the magnetic structures are much larger than the atomic lattice constant, but at the same time much smaller than the sample size. In computer simulations, the smallest exchange length serves as an estimate for the largest cell size admissible to prevent appreciable discretization errors. This general rule is not valid in special situations where the magnetization becomes particularly inhomogeneous. When such strongly inhomogeneous structures develop, micromagnetic simulations inevitably contain systematic and numerical errors. It is suggested to combine micromagnetic theory with a Heisenberg model to resolve such problems. We analyze cases where strongly inhomogeneous structures pose limits to standard micromagnetic simulations, arising from fundamental aspects as well as from numerical drawbacks. - Highlights: • We discuss the impact of strong inhomogeneities on micromagnetic simulations. • Analysis of fundamental and numerical errors in micromagnetic point singularities. • Numerical and methodological errors in exchange energy terms are quantified. • Suggestion to combine atomistic Heisenberg models with micromagnetism in such cases.

  8. Strong Interaction Studies with PANDA at FAIR

    Directory of Open Access Journals (Sweden)

    Schönning Karin

    2016-01-01

    Full Text Available The Facility for Antiproton and Ion Research (FAIR in Darmstadt, Germany, provides unique possibilities for a new generation of nuclear-, hadron- and atomic physics experiments. The future PANDA experiment at FAIR will offer a broad physics programme with emphasis on different aspects of hadron physics. Understanding the strong interaction in the perturbative regime remains one of the greatest challenges in contemporary physics and hadrons provide several important keys. In these proceedings, PANDA will be presented along with some high-lights of the planned physics programme.

  9. Strong Interaction Studies with PANDA at FAIR

    Science.gov (United States)

    Schönning, Karin

    2016-10-01

    The Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany, provides unique possibilities for a new generation of nuclear-, hadron- and atomic physics experiments. The future PANDA experiment at FAIR will offer a broad physics programme with emphasis on different aspects of hadron physics. Understanding the strong interaction in the perturbative regime remains one of the greatest challenges in contemporary physics and hadrons provide several important keys. In these proceedings, PANDA will be presented along with some high-lights of the planned physics programme.

  10. Momentum transport in strongly coupled anisotropic plasmas in the presence of strong magnetic fields

    CERN Document Server

    Finazzo, Stefano Ivo; Rougemont, Romulo; Noronha, Jorge

    2016-01-01

    We present a holographic perspective on momentum transport in strongly coupled, anisotropic non-Abelian plasmas in the presence of strong magnetic fields. We compute the anisotropic heavy quark drag forces and Langevin diffusion coefficients and also the anisotropic shear viscosities for two different holographic models, namely, a top-down deformation of strongly coupled $\\mathcal{N} = 4$ Super-Yang-Mills (SYM) theory triggered by an external Abelian magnetic field, and a bottom-up Einstein-Maxwell-dilaton (EMD) model which is able to provide a quantitative description of lattice QCD thermodynamics with $(2+1)$-flavors at both zero and nonzero magnetic fields. We find that, in general, energy loss and momentum diffusion through strongly coupled anisotropic plasmas are enhanced by a magnetic field being larger in transverse directions than in the direction parallel to the magnetic field. Moreover, the anisotropic shear viscosity coefficient is smaller in the direction of the magnetic field than in the plane pe...

  11. Disordered strongly correlated electronic systems

    Science.gov (United States)

    Javan Mard, Hossein

    Disorder can have a vast variety of consequences for the physics of phase transitions. Some transitions remain unchanged in the presence of disorder while others are completely destroyed. In this dissertation we study the effects of quenched disorder on electronic systmens at zero temperature. First, we perform variational studies of the interaction-localization problem to describe the interaction-induced renormalizations of the effective (screened) random potential seen by quasiparticles. Here we present results of careful finite-size scaling studies for the conductance of disordered Hubbard chains at half-filling and zero temperature. While our results indicate that quasiparticle wave functions remain exponentially localized even in the presence of moderate to strong repulsive interactions, we show that interactions produce a strong decrease of the characteristic conductance scale g* signaling the crossover to strong localization. This effect, which cannot be captured by a simple renormalization of the disorder strength, instead reflects a peculiar non-Gaussian form of the spatial correlations of the screened disordered potential, a hitherto neglected mechanism to dramatically reduce the impact of Anderson localization (interference) effects. Second, we formulate a strong-disorder renormalization-group (SDRG) approach to study the beta function of the tight-binding model in one dimension with both diagonal and off-diagonal disorder for states at the band center. We show that the SDRG method, when used to compute transport properties, yields exact results since it is identical to the transfer matrix method. The beta function is shown to be universal when only off-diagonal disorder is present even though single-parameter scaling is known to be violated. A different single-parameter scaling theory is formulated for this particular (particle-hole symmetric) case. Upon breaking particle-hole symmetry (by adding diagonal disorder), the beta function is shown to

  12. Strong interaction studies with kaonic atoms

    CERN Document Server

    Marton, J; Beer, G; Berucci, C; Bosnar, D; Bragadireanu, A M; Cargnelli, M; Clozza, A; Curceanu, C; d'Uffizi, A; Fiorini, C; Ghio, F; Guaraldo, C; Hayano, R; Iliescu, M; Ishiwatari, T; Iwasaki, M; Sandri, P Levi; Okada, S; Pietreanu, D; Piscicchia, K; Ponta, T; Quaglia, R; Vidal, A Romero; Sbardella, E; Scordo, A; Shi, H; Sirghi, D L; Sirghi, F; Tatsuno, H; Doce, O Vazquez; Widmann, E; Zmeskal, J

    2016-01-01

    The strong interaction of antikaons with nucleons and nuclei in the low-energy regime represents an active research field connected intrinsically with few-body physics. There are important open questions like the question of antikaon nuclear bound states. A unique and rather direct experimental access to the antikaon-nucleon scattering lengths is provided by precision X-ray spectroscopy of transitions in low-lying states of light kaonic atoms like kaonic hydrogen isotopes. In the SIDDHARTA experiment at the electron-positron collider DAFNE of LNF-INFN we measured the most precise values of the strong interaction observables, i.e. the strong interaction on the 1s ground state of the electromagnetically bound kaonic hydrogen atom leading to a hadronic shift and a hadronic broadening of the 1s state. The SIDDHARTA result triggered new theoretical work which achieved major progress in the understanding of the low-energy strong interaction with strangeness. Antikaon-nucleon scattering lengths have been calculated ...

  13. Strong interaction studies with kaonic atoms

    CERN Document Server

    Marton, J; Beer, G; Berucci, C; Bosnar, D; Bragadireanu, A M; Cargnelli, M; Clozza, A; Curceanu, C; d'Uffizi, A; Fiorini, C; Ghio, F; Guaraldo, C; Hayano, R; Iliescu, M; Ishiwatari, T; Iwasaki, M; Sandri, P Levi; Okada, S; Pietreanu, D; Piscicchia, K; Ponta, T; Quaglia, R; Vidal, A Romero; Sbardella, E; Scordo, A; Shi, H; Sirghi, D L; Sirghi, F; Tatsuno, H; Doce, O Vazquez; Widmann, E; Zmeskal, J

    2015-01-01

    The strong interaction of antikaons (K-) with nucleons and nuclei in the low energy regime represents an active research field connected intrinsically with few-body physics. There are important open questions like the question of antikaon nuclear bound states - the prototype system being K-pp. A unique and rather direct experimental access to the antikaon-nucleon scattering lengths is provided by precision X-ray spectroscopy of transitions in low-lying states of light kaonic atoms like kaonic hydrogen isotopes. In the SIDDHARTA experiment at the electron-positron collider DA?NE of LNF-INFN we measured the most precise values of the strong interaction observables, i.e. the strong interaction on the 1s ground state of the electromagnetically bound K-p atom leading to a hadronic shift and a hadronic broadening of the 1s state. The SIDDHARTA result triggered new theoretical work which achieved major progress in the understanding of the low-energy strong interaction with strangeness. Antikaon-nucleon scattering le...

  14. Dependent rational providers.

    Science.gov (United States)

    Brothers, Kyle B

    2011-04-01

    Provider claims to conscientious objection have generated a great deal of heated debate in recent years. However, the conflicts that arise when providers make claims to the "conscience" are only a subset of the more fundamental challenges that arise in health care practice when patients and providers come into conflict. In this piece, the author provides an account of patient-provider conflict from within the moral tradition of St. Thomas Aquinas. He argues that the practice of health care providers should be understood as a form of practical reasoning and that this practical reasoning must necessarily incorporate both "moral" and "professional" commitments. In order to understand how the practical reasoning of provider should account for the needs and commitments of the patient and vice versa, he explores the account of dependence provided by Alasdair MacIntyre in his book Dependent Rational Animals. MacIntyre argues that St. Thomas' account of practical reasoning should be extended and adapted to account for the embodied vulnerability of all humans. In light of this insight, providers must view patients not only as the subjects of their moral reflection but also as fellow humans upon whom the provider depends for feedback on the effectiveness and relevance of her practical reasoning. The author argues that this account precludes responsive providers from adopting either moral or professional conclusions on the appropriateness of interventions outside the individual circumstances that arise in particular situations. The adoption of this orientation toward patients will neither eradicate provider-patient conflict nor compel providers to perform interventions to which they object. But this account does require that providers attend meaningfully to the suffering of patients and seek feedback on whether their intervention has effectively addressed that suffering.

  15. PREFACE: Strongly correlated electron systems Strongly correlated electron systems

    Science.gov (United States)

    Saxena, Siddharth S.; Littlewood, P. B.

    2012-07-01

    This special section is dedicated to the Strongly Correlated Electron Systems Conference (SCES) 2011, which was held from 29 August-3 September 2011, in Cambridge, UK. SCES'2011 is dedicated to 100 years of superconductivity and covers a range of topics in the area of strongly correlated systems. The correlated electronic and magnetic materials featured include f-electron based heavy fermion intermetallics and d-electron based transition metal compounds. The selected papers derived from invited presentations seek to deepen our understanding of the rich physical phenomena that arise from correlation effects. The focus is on quantum phase transitions, non-Fermi liquid phenomena, quantum magnetism, unconventional superconductivity and metal-insulator transitions. Both experimental and theoretical work is presented. Based on fundamental advances in the understanding of electronic materials, much of 20th century materials physics was driven by miniaturisation and integration in the electronics industry to the current generation of nanometre scale devices. The achievements of this industry have brought unprecedented advances to society and well-being, and no doubt there is much further to go—note that this progress is founded on investments and studies in the fundamentals of condensed matter physics from more than 50 years ago. Nevertheless, the defining challenges for the 21st century will lie in the discovery in science, and deployment through engineering, of technologies that can deliver the scale needed to have an impact on the sustainability agenda. Thus the big developments in nanotechnology may lie not in the pursuit of yet smaller transistors, but in the design of new structures that can revolutionise the performance of solar cells, batteries, fuel cells, light-weight structural materials, refrigeration, water purification, etc. The science presented in the papers of this special section also highlights the underlying interest in energy-dense materials, which

  16. Strongly interacting light dark matter

    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

    In the presence of approximate global symmetries that forbid relevant interactions, strongly coupled light Dark Matter (DM) can appear weakly coupled at small-energy and generate a sizable relic abundance. Fundamental principles like unitarity restrict these symmetries to a small class, where the leading interactions are captured by effective operators up to dimension-8. Chiral symmetry, spontaneously broken global symmetries and non-linearly realized supersymmetry are examples of this. Their DM candidates (composite fermions, pseudo-Nambu-Goldstone Bosons and Goldstini) are interesting targets for LHC missing-energy searches.

  17. Strongly Interacting Light Dark Matter

    CERN Document Server

    Bruggisser, Sebastian; Urbano, Alfredo

    2016-01-01

    In the presence of approximate global symmetries that forbid relevant interactions, strongly coupled light Dark Matter (DM) can appear weakly coupled at small energy and generate a sizable relic abundance. Fundamental principles like unitarity restrict these symmetries to a small class, where the leading interactions are captured by effective operators up to dimension-8. Chiral symmetry, spontaneously broken global symmetries and non-linearly realized supersymmetry are examples of this. Their DM candidates (composite fermions, pseudo Nambu-Goldstone Bosons and Goldstini) are interesting targets for LHC missing-energy searches.

  18. Strong Completeness for Markovian Logics

    DEFF Research Database (Denmark)

    Kozen, Dexter; Mardare, Radu Iulian; Panangaden, Prakash

    2013-01-01

    In this paper we present Hilbert-style axiomatizations for three logics for reasoning about continuous-space Markov processes (MPs): (i) a logic for MPs defined for probability distributions on measurable state spaces, (ii) a logic for MPs defined for sub-probability distributions and (iii) a logic...... defined for arbitrary distributions. These logics are not compact so one needs infinitary rules in order to obtain strong completeness results. We propose a new infinitary rule that replaces the so-called Countable Additivity Rule (CAR) currently used in the literature to address the problem of proving...

  19. Is Global Strong Wind Declining?

    Institute of Scientific and Technical Information of China (English)

    Zongci Zhao; Yong Luo; Ying Jiang

    2011-01-01

    1 Introduction To mitigate global warming,the call for using clean energy,developing low-carbon economy and initiating green environmental protection has never been louder.One of the hot topics,which has received widespread attentions in the world,is the development and utilization of wind energy.At the same time,some of the climate change studies focus on the changes in global wind speeds and strong winds which are related to wind energy utilization.The issues,which are the subjects of these studies,can be summarized in the following.

  20. The INGV Real Time Strong Motion Database

    Science.gov (United States)

    Massa, Marco; D'Alema, Ezio; Mascandola, Claudia; Lovati, Sara; Scafidi, Davide; Gomez, Antonio; Carannante, Simona; Franceschina, Gianlorenzo; Mirenna, Santi; Augliera, Paolo

    2017-04-01

    The INGV real time strong motion data sharing is assured by the INGV Strong Motion Database. ISMD (http://ismd.mi.ingv.it) was designed in the last months of 2011 in cooperation among different INGV departments, with the aim to organize the distribution of the INGV strong-motion data using standard procedures for data acquisition and processing. The first version of the web portal was published soon after the occurrence of the 2012 Emilia (Northern Italy), Mw 6.1, seismic sequence. At that time ISMD was the first European real time web portal devoted to the engineering seismology community. After four years of successfully operation, the thousands of accelerometric waveforms collected in the archive need necessary a technological improvement of the system in order to better organize the new data archiving and to make more efficient the answer to the user requests. ISMD 2.0 was based on PostgreSQL (www.postgresql.org), an open source object- relational database. The main purpose of the web portal is to distribute few minutes after the origin time the accelerometric waveforms and related metadata of the Italian earthquakes with ML≥3.0. Data are provided both in raw SAC (counts) and automatically corrected ASCII (gal) formats. The web portal also provide, for each event, a detailed description of the ground motion parameters (i.e. Peak Ground Acceleration, Velocity and Displacement, Arias and Housner Intensities) data converted in velocity and displacement, response spectra up to 10.0 s and general maps concerning the recent and the historical seismicity of the area together with information about its seismic hazard. The focal parameters of the events are provided by the INGV National Earthquake Center (CNT, http://cnt.rm.ingv.it). Moreover, the database provides a detailed site characterization section for each strong motion station, based on geological, geomorphological and geophysical information. At present (i.e. January 2017), ISMD includes 987 (121

  1. Strong sequences and independent sets

    Directory of Open Access Journals (Sweden)

    Joanna Jureczko

    2016-05-01

    Full Text Available A family $\\mathcal{S} \\in \\mathcal{P}(\\omega$ is \\textit{an independent family} if for each pair $\\mathcal{A, B}$ of disjoint finite subsets of $\\mathcal{S}$ the set $\\bigcap \\mathcal{A} \\cap (\\omega \\setminus \\bigcup \\mathcal{B}$ is nonempty. The fact that there is an independent family on $\\omega$ of size continuum was proved by Fichtenholz and Kantorowicz in \\cite{FK}. If we substitute $\\mathcal{P}(\\omega$ by a set $(X, r$ with arbitrary relation \\textit{r} it is natural question about existence and length of an independent set on $(X, r$. In this paper special assumptions of such existence will be considered. On the other hand in 60s' of the last century the strong sequences method was introduced by Efimov. He used it for proving some famous theorems in dyadic spaces like: Marczewski theorem on cellularity, Shanin theorem on a calibre, Esenin-Volpin theorem and others. In this paper there will be considered: length of strong sequences, the length of independent sets and other well known cardinal invariants and there will be examined inequalities among them.

  2. Interference Channels with Strong Secrecy

    CERN Document Server

    He, Xiang

    2009-01-01

    It is known that given the real sum of two independent uniformly distributed lattice points from the same nested lattice codebook, the eavesdropper can obtain at most 1 bit of information per channel regarding the value of one of the lattice points. In this work, we study the effect of this 1 bit information on the equivocation expressed in three commonly used information theoretic measures, i.e., the Shannon entropy, the Renyi entropy and the min entropy. We then demonstrate its applications in an interference channel with a confidential message. In our previous work, we showed that nested lattice codes can outperform Gaussian codes for this channel when the achieved rate is measured with the weak secrecy notion. Here, with the Renyi entropy and the min entropy measure, we prove that the same secure degree of freedom is achievable with the strong secrecy notion as well. A major benefit of the new coding scheme is that the strong secrecy is generated from a single lattice point instead of a sequence of lattic...

  3. Intracontinental basins and strong earthquakes

    Institute of Scientific and Technical Information of China (English)

    邓起东; 高孟潭; 赵新平; 吴建春

    2004-01-01

    The September 17, 1303 Hongtong M=8 earthquake occurred in Linfen basin of Shanxi down-faulted basin zone. It is the first recorded M=8 earthquake since the Chinese historical seismic records had started and is a great earthquake occurring in the active intracontinental basin. We had held a Meeting of the 700th Anniversary of the 1303 Hongtong M=8 Earthquake in Shanxi and a Symposium on Intracontinental Basins and Strong Earthquakes in Taiyuan City of Shanxi Province on September 17~18, 2003. The articles presented on the symposium discussed the relationships between active intracontinental basins of different properties, developed in different regions, including tensional graben and semi-graben basins in tensile tectonic regions, compression-depression basins and foreland basins in compressive tectonic regions and pull-apart basins in strike-slip tectonic zones, and strong earthquakes in China. In this article we make a brief summary of some problems. The articles published in this special issue are a part of the articles presented on the symposium.

  4. Vector mesons in strongly interacting matter

    Indian Academy of Sciences (India)

    Volker Metag

    2010-08-01

    Properties of hadrons in strongly interacting matter provide a link between quantum chromodynamics in the strong coupling regime and experimental observables. QCD sum rules show that changes in chiral and higher-order condensates, partially associated with a restoration of chiral symmetry in the nuclear medium, will lead to significant changes in the low-energy spectrum of hadrons. Heavy-ion collisions and reactions with elementary probes have been used to extract experimental information on in-medium properties of hadrons. Results on the light vector mesons ρ, , and , are summarized and compared. Almost all experiments report a softening of the spectral functions with increases in width depending on the density and temperature of the hadronic environment. No evidence for mass shifts is found in majority of the experiments. Remaining inconsistencies among experimental results demonstrate the need for further measurements with higher statistics and inrceased acceptance in particular for low-momentum vector mesons.

  5. Strong ground motion prediction using virtual earthquakes.

    Science.gov (United States)

    Denolle, M A; Dunham, E M; Prieto, G A; Beroza, G C

    2014-01-24

    Sedimentary basins increase the damaging effects of earthquakes by trapping and amplifying seismic waves. Simulations of seismic wave propagation in sedimentary basins capture this effect; however, there exists no method to validate these results for earthquakes that have not yet occurred. We present a new approach for ground motion prediction that uses the ambient seismic field. We apply our method to a suite of magnitude 7 scenario earthquakes on the southern San Andreas fault and compare our ground motion predictions with simulations. Both methods find strong amplification and coupling of source and structure effects, but they predict substantially different shaking patterns across the Los Angeles Basin. The virtual earthquake approach provides a new approach for predicting long-period strong ground motion.

  6. Heavy Diquark Symmetry Constraints for Strong Decays

    CERN Document Server

    Eakins, B

    2012-01-01

    The Heavy Diquark Symmetry (HDS) of Doubly Heavy Baryons (DHBs) provides new insights into the spectroscopy of these hadrons. We derive the consequences of this symmetry for the mass spectra and the decay widths of DHBs. We compare these symmetry constraints to results from a nonrelativistic quark model for the mass spectra and results from the $^3P_0$ model for strong decays. The quark model we implement was not constructed with these symmetries and contains interactions which explicitly break HDS, nevertheless these symmetries emerge. We argue that the $^3P_0$ model and any other model for strong transitions which employs a spectator assumption explicitly respects HDS. We also explore the possibility of treating the strange quark as a heavy quark and apply these ideas to $\\Xi$, $\\Xi_c$, and $\\Xi_b$ baryons.

  7. Quadratic gravity: from weak to strong

    CERN Document Server

    Holdom, Bob

    2016-01-01

    More than three decades ago quadratic gravity was found to present a perturbative, renormalizable and asymptotically free theory of quantum gravity. Unfortunately the theory appeared to have problems with a spin-2 ghost. In this essay we revisit quadratic gravity in a different light by considering the case that the asymptotically free interaction flows to a strongly interacting regime. This occurs when the coefficient of the Einstein-Hilbert term is smaller than the scale $\\Lambda_{\\mathrm{QG}}$ where the quadratic couplings grow strong. Here QCD provides some useful insights. By pushing the analogy with QCD, we conjecture that the nonperturbative effects can remove the naive spin-2 ghost and lead to the emergence of general relativity in the IR.

  8. Electroweak and Strong Interactions Phenomenology, Concepts, Models

    CERN Document Server

    Scheck, Florian

    2012-01-01

    Electroweak and Strong Interaction: Phenomenology, Concepts, Models, begins with relativistic quantum mechanics and some quantum field theory which lay the foundation for the rest of the text. The phenomenology and the physics of the fundamental interactions are emphasized through a detailed discussion of the empirical fundamentals of unified theories of strong, electromagnetic, and weak interactions. The principles of local gauge theories are described both in a heuristic and a geometric framework. The minimal standard model of the fundamental interactions is developed in detail and characteristic applications are worked out. Possible signals of physics beyond that model, notably in the physics of neutrinos are also discussed. Among the applications scattering on nucleons and on nuclei provide salient examples. Numerous exercises with solutions make the text suitable for advanced courses or individual study. This completely updated revised new edition contains an enlarged chapter on quantum chromodynamics an...

  9. Strong gravitational lensing and dark energy complementarity

    Energy Technology Data Exchange (ETDEWEB)

    Linder, Eric V.

    2004-01-21

    In the search for the nature of dark energy most cosmological probes measure simple functions of the expansion rate. While powerful, these all involve roughly the same dependence on the dark energy equation of state parameters, with anticorrelation between its present value w{sub 0} and time variation w{sub a}. Quantities that have instead positive correlation and so a sensitivity direction largely orthogonal to, e.g., distance probes offer the hope of achieving tight constraints through complementarity. Such quantities are found in strong gravitational lensing observations of image separations and time delays. While degeneracy between cosmological parameters prevents full complementarity, strong lensing measurements to 1 percent accuracy can improve equation of state characterization by 15-50 percent. Next generation surveys should provide data on roughly 105 lens systems, though systematic errors will remain challenging.

  10. Provider Health and Wellness.

    Science.gov (United States)

    Nanda, Anil; Wasan, Anita; Sussman, James

    2017-07-19

    Provider health and wellness is a significant issue and can impact patient care, including patient satisfaction, quality of care, medical errors, malpractice risk, as well as provider and office staff turnover and early retirement. Health and wellness encompasses various areas including burnout, depression, divorce, and suicide and affects providers of all specialties and at all levels of training. Providers deal with many everyday stresses, including electronic health records, office politics, insurance and billing issues, dissatisfied patients, and their own personal and family issues. Approximately half of all physicians suffer from burnout, and the rate of burnout among physicians of all specialties is increasing. An important first step in dealing with burnout is recognition and then seeking assistance. Strategies to prevent and treat burnout include increasing provider resiliency as well as implementing practical changes in the everyday practice of medicine. There is currently very little data regarding health and wellness specifically in the field of allergy and immunology, and studies are necessary to determine the prevalence of burnout and related issues in this field. Many medical specialties as well as state and national medical associations have health and wellness committees and other resources, which are essential for providers. Health and wellness programs should be introduced early in a provider's training and continued throughout a provider's career. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  11. Engineering applications of strong ground motion simulation

    Science.gov (United States)

    Somerville, Paul

    1993-02-01

    The formulation, validation and application of a procedure for simulating strong ground motions for use in engineering practice are described. The procedure uses empirical source functions (derived from near-source strong motion recordings of small earthquakes) to provide a realistic representation of effects such as source radiation that are difficult to model at high frequencies due to their partly stochastic behavior. Wave propagation effects are modeled using simplified Green's functions that are designed to transfer empirical source functions from their recording sites to those required for use in simulations at a specific site. The procedure has been validated against strong motion recordings of both crustal and subduction earthquakes. For the validation process we choose earthquakes whose source models (including a spatially heterogeneous distribution of the slip of the fault) are independently known and which have abundant strong motion recordings. A quantitative measurement of the fit between the simulated and recorded motion in this validation process is used to estimate the modeling and random uncertainty associated with the simulation procedure. This modeling and random uncertainty is one part of the overall uncertainty in estimates of ground motions of future earthquakes at a specific site derived using the simulation procedure. The other contribution to uncertainty is that due to uncertainty in the source parameters of future earthquakes that affect the site, which is estimated from a suite of simulations generated by varying the source parameters over their ranges of uncertainty. In this paper, we describe the validation of the simulation procedure for crustal earthquakes against strong motion recordings of the 1989 Loma Prieta, California, earthquake, and for subduction earthquakes against the 1985 Michoacán, Mexico, and Valparaiso, Chile, earthquakes. We then show examples of the application of the simulation procedure to the estimatation of the

  12. Tailoring strong lensing cosmographic observations

    Science.gov (United States)

    Linder, Eric V.

    2015-04-01

    Strong lensing time delay cosmography has excellent complementarity with other dark energy probes and will soon have abundant systems detected. We investigate two issues in the imaging and spectroscopic follow-up required to obtain the time delay distance. The first is optimization of spectroscopic resources. We develop a code to optimize the cosmological leverage under the constraint of constant spectroscopic time and find that sculpting the lens system redshift distribution can deliver a 40% improvement in dark energy figure of merit. The second is the role of systematics, correlated between different quantities of a given system or model errors common to all systems. We show how the levels of different systematics affect the cosmological parameter estimation and derive guidance for the fraction of double image vs quad image systems to follow as a function of differing systematics between them.

  13. Breathers in strongly anharmonic lattices.

    Science.gov (United States)

    Rosenau, Philip; Pikovsky, Arkady

    2014-02-01

    We present and study a family of finite amplitude breathers on a genuinely anharmonic Klein-Gordon lattice embedded in a nonlinear site potential. The direct numerical simulations are supported by a quasilinear Schrodinger equation (QLS) derived by averaging out the fast oscillations assuming small, albeit finite, amplitude vibrations. The genuinely anharmonic interlattice forces induce breathers which are strongly localized with tails evanescing at a doubly exponential rate and are either close to a continuum, with discrete effects being suppressed, or close to an anticontinuum state, with discrete effects being enhanced. Whereas the D-QLS breathers appear to be always stable, in general there is a stability threshold which improves with spareness of the lattice.

  14. Strong Langmuir turbulence at Jupiter?

    Science.gov (United States)

    Cairns, Iver H.; Robinson, P. A.

    1992-01-01

    Langmuir wave packets with short scale lengths less than an approximately equal to 100 lambda e have been observed in Jupiter's foreshock. Theoretical constraints on the electric fields and scale sizes of collapsing wave packets are summarized, extended and placed in a form suitable for easy comparison with Voyager and Ulysses data. The published data are reviewed and possible instrumental underestimation of fields discussed. New upper limits for the fields of the published wave packets are estimated. Wave packets formed at the nucleation scale from the observed large-scale fields cannot collapse because they are disrupted before collapse occurs. The published wave packets are quantitatively inconsistent with strong turbulence collapse. Strict constraints exist for more intense wave packets to be able to collapse: E greater than or approximately equals to 1-8 mV/m for scales less than or approximately equal to 100 lambda e. Means for testing these conclusions using Voyager and Ulysses data are suggested.

  15. Electrophoresis in strong electric fields.

    Science.gov (United States)

    Barany, Sandor

    2009-01-01

    Two kinds of non-linear electrophoresis (ef) that can be detected in strong electric fields (several hundred V/cm) are considered. The first ("classical" non-linear ef) is due to the interaction of the outer field with field-induced ionic charges in the electric double layer (EDL) under conditions, when field-induced variations of electrolyte concentration remain to be small comparatively to its equilibrium value. According to the Shilov theory, the non-linear component of the electrophoretic velocity for dielectric particles is proportional to the cubic power of the applied field strength (cubic electrophoresis) and to the second power of the particles radius; it is independent of the zeta-potential but is determined by the surface conductivity of particles. The second one, the so-called "superfast electrophoresis" is connected with the interaction of a strong outer field with a secondary diffuse layer of counterions (space charge) that is induced outside the primary (classical) diffuse EDL by the external field itself because of concentration polarization. The Dukhin-Mishchuk theory of "superfast electrophoresis" predicts quadratic dependence of the electrophoretic velocity of unipolar (ionically or electronically) conducting particles on the external field gradient and linear dependence on the particle's size in strong electric fields. These are in sharp contrast to the laws of classical electrophoresis (no dependence of V(ef) on the particle's size and linear dependence on the electric field gradient). A new method to measure the ef velocity of particles in strong electric fields is developed that is based on separation of the effects of sedimentation and electrophoresis using videoimaging and a new flowcell and use of short electric pulses. To test the "classical" non-linear electrophoresis, we have measured the ef velocity of non-conducting polystyrene, aluminium-oxide and (semiconductor) graphite particles as well as Saccharomice cerevisiae yeast cells as a

  16. On the strongly coupled heterotic string

    CERN Document Server

    Dudas, E A; Dudas, Emilian; Mourad, Jihad

    1997-01-01

    We analyze in detail the anomaly cancellation conditions for the strongly coupled $E_8 \\times E_8$ heterotic string introduced by Horava and Witten and find new features compared to the ten-dimensional Green-Schwarz mechanism. We project onto ten dimensions the corresponding Lagrangian of the zero-mode fields. We find that it has a simple interpretation provided by the conjectured heterotic string/fivebrane duality. The part which originates from eleven-dimensions is naturally described in fivebrane language. We discuss physical couplings and scales in four dimensions.

  17. Gravitational leptogenesis, C, CP and strong equivalence

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, Jamie I.; Shore, Graham M. [Department of Physics, Swansea University,Swansea, SA2 8PP (United Kingdom)

    2015-02-12

    The origin of matter-antimatter asymmetry is one of the most important outstanding problems at the interface of particle physics and cosmology. Gravitational leptogenesis (baryogenesis) provides a possible mechanism through explicit couplings of spacetime curvature to appropriate lepton (or baryon) currents. In this paper, the idea that these strong equivalence principle violating interactions could be generated automatically through quantum loop effects in curved spacetime is explored, focusing on the realisation of the discrete symmetries C, CP and CPT which must be broken to induce matter-antimatter asymmetry. The related issue of quantum corrections to the dispersion relation for neutrino propagation in curved spacetime is considered within a fully covariant framework.

  18. Exactly solvable models of strongly correlated electrons

    CERN Document Server

    Korepin, Vladimir E

    1994-01-01

    Systems of strongly correlated electrons are at the heart of recent developments in condensed matter theory. They have applications to phenomena like high-T c superconductivity and the fractional quantum hall effect. Analytical solutions to such models, though mainly limited to one spatial dimension, provide a complete and unambiguous picture of the dynamics involved. This volume is devoted to such solutions obtained using the Bethe Ansatz, and concentrates on the most important of such models, the Hubbard model. The reprints are complemented by reviews at the start of each chapter and an exte

  19. Strong Ideal Convergence in Probabilistic Metric Spaces

    Indian Academy of Sciences (India)

    Celaleddin Şençimen; Serpil Pehlivan

    2009-06-01

    In the present paper we introduce the concepts of strongly ideal convergent sequence and strong ideal Cauchy sequence in a probabilistic metric (PM) space endowed with the strong topology, and establish some basic facts. Next, we define the strong ideal limit points and the strong ideal cluster points of a sequence in this space and investigate some properties of these concepts.

  20. Transport phenomena in strongly correlated Fermi liquids

    Energy Technology Data Exchange (ETDEWEB)

    Kontani, Hiroshi [Nagoya Univ., Aichi (Japan). Dept. of Physics

    2013-03-01

    Comprehensive overview. Written by an expert of this topic. Provides the reader with current developments in the field. In conventional metals, various transport coefficients are scaled according to the quasiparticle relaxation time, {tau}, which implies that the relaxation time approximation (RTA) holds well. However, such a simple scaling does not hold in many strongly correlated electron systems, reflecting their unique electronic states. The most famous example would be cuprate high-Tc superconductors (HTSCs), where almost all the transport coefficients exhibit a significant deviation from the RTA results. To better understand the origin of this discrepancy, we develop a method for calculating various transport coefficients beyond the RTA by employing field theoretical techniques. Near the magnetic quantum critical point, the current vertex correction (CVC), which describes the electron-electron scattering beyond the relaxation time approximation, gives rise to various anomalous transport phenomena. We explain anomalous transport phenomena in cuprate HTSCs and other metals near their magnetic or orbital quantum critical point using a uniform approach. We also discuss spin related transport phenomena in strongly correlated systems. In many d- and f-electron systems, the spin current induced by the spin Hall effect is considerably greater because of the orbital degrees of freedom. This fact attracts much attention due to its potential application in spintronics. We discuss various novel charge, spin and heat transport phenomena in strongly correlated metals.

  1. Doubling strong lensing as a cosmological probe

    Science.gov (United States)

    Linder, Eric V.

    2016-10-01

    Strong gravitational lensing provides a geometric probe of cosmology in a unique manner through distance ratios involving the source and lens. This is well-known for the time delay distance derived from measured delays between lightcurves of the images of variable sources such as quasars. Recently, double source plane lens systems involving two constant sources lensed by the same foreground lens have been proposed as another probe, involving a different ratio of distances measured from the image positions and fairly insensitive to the lens modeling. Here we demonstrate that these two different sets of strong lensing distance ratios have strong complementarity in cosmological leverage. Unlike other probes, the double source distance ratio is actually more sensitive to the dark energy equation of state parameters w0 and wa than to the matter density Ωm, for low redshift lenses. Adding double source distance ratio measurements can improve the dark energy figure of merit by 40% for a sample of fewer than 100 low redshift systems, or even better for the optimal redshift distribution we derive.

  2. Forecasting area of strong aftershock occurrence

    Science.gov (United States)

    Baranov, Sergey; Shebalin, Peter

    2016-04-01

    Forecasting an area of strong aftershock was never, at our knowledge, considered in terms of operational forecasting. Different declustering models exist to separate post-factum the aftershocks from "independent" events. Large number of studies discussed in previous years the form of the distribution of the aftershocks distances from the mainshock fault. Here we present results of our attempts to assimilate the above researches into a model that can be used in operational aftershock forecasting. Our study was based on data provided by ANSS catalog for 1980-2015. We tried more than 20 well known and suggested by ourselves models of aftershock areas to retrospective forecasting of strong aftershock areas. We tried the models based on data for 12 hours after a mainshock and estimated their forecast quality using special modification of L-test to achieve an optimal model. As a result of our study is a model that can be used in operational forecasting area of strong aftershocks. The research was supported by Russian Foundation for Basic Research (Project 16-05-00263A).

  3. A Strong Merger Shock in Abell 665

    Science.gov (United States)

    Dasadia, S.; Sun, M.; Sarazin, C.; Morandi, A.; Markevitch, M.; Wik, D.; Feretti, L.; Giovannini, G.; Govoni, F.; Vacca, V.

    2016-03-01

    Deep (103 ks) Chandra observations of Abell 665 have revealed rich structures in this merging galaxy cluster, including a strong shock and two cold fronts. The newly discovered shock has a Mach number of M = 3.0 ± 0.6, propagating in front of a cold disrupted cloud. This makes Abell 665 the second cluster, after the Bullet cluster, where a strong merger shock of M ≈ 3 has been detected. The shock velocity from jump conditions is consistent with (2.7 ± 0.7) × 103 km s-1. The new data also reveal a prominent southern cold front with potentially heated gas ahead of it. Abell 665 also hosts a giant radio halo. There is a hint of diffuse radio emission extending to the shock at the north, which needs to be examined with better radio data. This new strong shock provides a great opportunity to study the re-acceleration model with the X-ray and radio data combined.

  4. A Strong Merger Shock in Abell 665

    CERN Document Server

    Dasadia, Sarthak; Sarazin, Craig; Morandi, Andrea; Markevitch, Maxim; Wik, Daniel; Feretti, Luigina; Giovannini, Gabriele; Govoni, Federica; Vacca, Valentina

    2016-01-01

    Deep (103 ks) \\chandra\\ observations of Abell 665 have revealed rich structures in this merging galaxy cluster, including a strong shock and two cold fronts. The newly discovered shock has a Mach number of $M$ = 3.0 $\\pm$ 0.6, propagating in front of a cold disrupted cloud. This makes Abell~665 the second cluster where a strong merger shock of $M \\approx$ 3 has been detected, after the Bullet cluster. The shock velocity from jump conditions is consistent with (2.7 $\\pm$ 0.7) $\\times$ 10$^3$ km sec$^{-1}$. The new data also reveal a prominent southern cold front, with potentially heated gas ahead of it. Abell 665 also hosts a giant radio halo. There is a hint of diffuse radio emission extending to the shock at the north, which needs to be examined with better radio data. This new strong shock provides a great opportunity to study the re-acceleration model with the X-ray and radio data combined.

  5. Detracked--And Going Strong

    Science.gov (United States)

    Bavis, Peter

    2017-01-01

    In 2010, Evanston Township High School in suburban Chicago, Illinois, dramatically changed its freshman year for incoming students. The school detracked freshman English, history, and biology courses for the vast majority of students, thus removing barriers for historically under-represented student groups and providing greater access and…

  6. Strongly correlated perovskite fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, You; Guan, Xiaofei; Zhou, Hua; Ramadoss, Koushik; Adam, Suhare; Liu, Huajun; Lee, Sungsik; Shi, Jian; Tsuchiya, Masaru; Fong, Dillon D.; Ramanathan, Shriram

    2016-05-16

    Fuel cells convert chemical energy directly into electrical energy with high efficiencies and environmental benefits, as compared with traditional heat engines1, 2, 3, 4. Yttria-stabilized zirconia is perhaps the material with the most potential as an electrolyte in solid oxide fuel cells (SOFCs), owing to its stability and near-unity ionic transference number5. Although there exist materials with superior ionic conductivity, they are often limited by their ability to suppress electronic leakage when exposed to the reducing environment at the fuel interface. Such electronic leakage reduces fuel cell power output and the associated chemo-mechanical stresses can also lead to catastrophic fracture of electrolyte membranes6. Here we depart from traditional electrolyte design that relies on cation substitution to sustain ionic conduction. Instead, we use a perovskite nickelate as an electrolyte with high initial ionic and electronic conductivity. Since many such oxides are also correlated electron systems, we can suppress the electronic conduction through a filling-controlled Mott transition induced by spontaneous hydrogen incorporation. Using such a nickelate as the electrolyte in free-standing membrane geometry, we demonstrate a low-temperature micro-fabricated SOFC with high performance. The ionic conductivity of the nickelate perovskite is comparable to the best-performing solid electrolytes in the same temperature range, with a very low activation energy. The results present a design strategy for high-performance materials exhibiting emergent properties arising from strong electron correlations.

  7. John Strong - 1941-2006

    CERN Multimedia

    2006-01-01

    Our friend and colleague John Strong was cruelly taken from us by a brain tumour on 31 July, a few days before his 65th birthday. John started his career and obtained his PhD in a group from Westfield College, initially working on experiments at Rutherford Appleton Laboratory (RAL). From the early 1970s onwards, however, his research was focused on experiments in CERN, with several particularly notable contributions. The Omega spectrometer adopted a system John had originally developed for experiments at RAL using vidicon cameras (a type of television camera) to record the sparks in the spark chambers. This highly automated system allowed Omega to be used in a similar way to bubble chambers. He contributed to the success of NA1 and NA7, where he became heavily involved in the electronic trigger systems. In these experiments the Westfield group joined forces with Italian colleagues to measure the form factors of the pion and the kaon, and the lifetime of some of the newly discovered charm particles. Such h...

  8. Broad Leaves in Strong Flow

    CERN Document Server

    Miller, Laura

    2013-01-01

    Flexible broad leaves are thought to reconfigure in the wind and water to reduce the drag forces that act upon them. Simple mathematical models of a flexible beam immersed in a two-dimensional flow will also exhibit this behavior. What is less understood is how the mechanical properties of a leaf in a three-dimensional flow will passively allow roll up into a cone shape and reduce both drag and vortex induced oscillations. In this fluid dynamics video, the flows around the leaves are compared with those of simplified sheets using 3D numerical simulations and physical models. For some reconfiguration shapes, large forces and oscillations due to strong vortex shedding are produced. In the actual leaf, a stable recirculation zone is formed within the wake of the reconfigured cone. In physical and numerical models that reconfigure into cones, a similar recirculation zone is observed with both rigid and flexible tethers. These results suggest that the three-dimensional cone structure in addition to flexibility is ...

  9. Strongly correlated perovskite fuel cells

    Science.gov (United States)

    Zhou, You; Guan, Xiaofei; Zhou, Hua; Ramadoss, Koushik; Adam, Suhare; Liu, Huajun; Lee, Sungsik; Shi, Jian; Tsuchiya, Masaru; Fong, Dillon D.; Ramanathan, Shriram

    2016-06-01

    Fuel cells convert chemical energy directly into electrical energy with high efficiencies and environmental benefits, as compared with traditional heat engines. Yttria-stabilized zirconia is perhaps the material with the most potential as an electrolyte in solid oxide fuel cells (SOFCs), owing to its stability and near-unity ionic transference number. Although there exist materials with superior ionic conductivity, they are often limited by their ability to suppress electronic leakage when exposed to the reducing environment at the fuel interface. Such electronic leakage reduces fuel cell power output and the associated chemo-mechanical stresses can also lead to catastrophic fracture of electrolyte membranes. Here we depart from traditional electrolyte design that relies on cation substitution to sustain ionic conduction. Instead, we use a perovskite nickelate as an electrolyte with high initial ionic and electronic conductivity. Since many such oxides are also correlated electron systems, we can suppress the electronic conduction through a filling-controlled Mott transition induced by spontaneous hydrogen incorporation. Using such a nickelate as the electrolyte in free-standing membrane geometry, we demonstrate a low-temperature micro-fabricated SOFC with high performance. The ionic conductivity of the nickelate perovskite is comparable to the best-performing solid electrolytes in the same temperature range, with a very low activation energy. The results present a design strategy for high-performance materials exhibiting emergent properties arising from strong electron correlations.

  10. Cosmology with Strong Lensing Systems

    CERN Document Server

    Cao, Shuo; Gavazzi, Raphaël; Piórkowska, Aleksandra; Zhu, Zong-Hong

    2015-01-01

    In this paper, we assemble a catalog of 118 strong gravitational lensing systems from SLACS, BELLS, LSD and SL2S surveys and use them to constrain the cosmic equation of state. In particular we consider two cases of dark energy phenomenology: $XCDM$ model where dark energy is modeled by a fluid with constant $w$ equation of state parameter and in Chevalier - Polarski - Linder (CPL) parametrization where $w$ is allowed to evolve with redshift: $w(z) = w_0 + w_1 \\frac{z}{1+z}$. We assume spherically symmetric mass distribution in lensing galaxies, but relax the rigid assumption of SIS model in favor to more general power-law index $\\gamma$, also allowing it to evolve with redshifts $\\gamma(z)$. Our results for the $XCDM$ cosmology show the agreement with values (concerning both $w$ and $\\gamma$ parameters) obtained by other authors. We go further and constrain the CPL parameters jointly with $\\gamma(z)$. The resulting confidence regions for the parameters are much better than those obtained with a similar metho...

  11. Strongly correlated perovskite fuel cells.

    Science.gov (United States)

    Zhou, You; Guan, Xiaofei; Zhou, Hua; Ramadoss, Koushik; Adam, Suhare; Liu, Huajun; Lee, Sungsik; Shi, Jian; Tsuchiya, Masaru; Fong, Dillon D; Ramanathan, Shriram

    2016-06-09

    Fuel cells convert chemical energy directly into electrical energy with high efficiencies and environmental benefits, as compared with traditional heat engines. Yttria-stabilized zirconia is perhaps the material with the most potential as an electrolyte in solid oxide fuel cells (SOFCs), owing to its stability and near-unity ionic transference number. Although there exist materials with superior ionic conductivity, they are often limited by their ability to suppress electronic leakage when exposed to the reducing environment at the fuel interface. Such electronic leakage reduces fuel cell power output and the associated chemo-mechanical stresses can also lead to catastrophic fracture of electrolyte membranes. Here we depart from traditional electrolyte design that relies on cation substitution to sustain ionic conduction. Instead, we use a perovskite nickelate as an electrolyte with high initial ionic and electronic conductivity. Since many such oxides are also correlated electron systems, we can suppress the electronic conduction through a filling-controlled Mott transition induced by spontaneous hydrogen incorporation. Using such a nickelate as the electrolyte in free-standing membrane geometry, we demonstrate a low-temperature micro-fabricated SOFC with high performance. The ionic conductivity of the nickelate perovskite is comparable to the best-performing solid electrolytes in the same temperature range, with a very low activation energy. The results present a design strategy for high-performance materials exhibiting emergent properties arising from strong electron correlations.

  12. <strong>On Determinism in Modal Transition Systemsstrong>

    DEFF Research Database (Denmark)

    Benes, Nikola; Kretinsky, Jan; Larsen, Kim Guldstrand

    2009-01-01

    with respect to the semantic view based on the sets of the implementations of a given MTS specification. Recent work indicates that some of these limitations might be overcome by considering deterministic systems, which seem to be more manageable but still interesting for several application areas....... In the present article, we provide a comprehensive account of the MTS framework in the deterministic setting. We study a number of problems previously considered on MTS and point out to what extend we can expect better results under the restriction of determinism....

  13. <strong>Shop stewards' learning and union strategiesstrong>

    DEFF Research Database (Denmark)

    Warring, Niels

    2007-01-01

    In Denmark the trade unions have well established educational systems providing the shop stewards with a variety of competencies. Union courses have been analysed focusing on shop stewards' satisfaction with the content and the practical impact of the courses. However, little attention has been...... different theoretical traditions: Shop steward's learning is situational, relational and cross-contextual. Shop stewards' learning is lifelong and life wide. And shop stewards' learning is closely connected to the development of the labour market and not least the unions' priorities, interpretation...

  14. <strong>Shop stewards' learning and union strategiesstrong>

    DEFF Research Database (Denmark)

    Warring, Niels

    2007-01-01

    In Denmark the trade unions have well established educational systems providing the shop stewards with a variety of competencies. Union courses have been analysed focusing on shop stewards' satisfaction with the content and the practical impact of the courses. However, little attention has been...... different theoretical traditions: Shop steward's learning is situational, relational and cross-contextual. Shop stewards' learning is lifelong and life wide. And shop stewards' learning is closely connected to the development of the labour market and not least the unions' priorities, interpretation...... perspectives as well as socio-cultural and political theories....

  15. Strong interaction studies with kaonic atoms

    Directory of Open Access Journals (Sweden)

    Marton J.

    2016-01-01

    Full Text Available The strong interaction of antikaons (K− with nucleons and nuclei in the low-energy regime represents an active research field connected intrinsically with few-body physics. There are important open questions like the question of antikaon nuclear bound states - the prototype system being K−pp. A unique and rather direct experimental access to the antikaon-nucleon scattering lengths is provided by precision X-ray spectroscopy of transitions in low-lying states of light kaonic atoms like kaonic hydrogen isotopes. In the SIDDHARTA experiment at the electron-positron collider DAΦNE of LNF-INFN we measured the most precise values of the strong interaction observables, i.e. the strong interaction on the 1s ground state of the electromagnetically bound K−p atom leading to a hadronic shift ϵ1s and a hadronic broadening Γ1s of the 1s state. The SIDDHARTA result triggered new theoretical work which achieved major progress in the understanding of the low-energy strong interaction with strangeness. Antikaon-nucleon scattering lengths have been calculated constrained by the SIDDHARTA data on kaonic hydrogen. For the extraction of the isospin-dependent scattering lengths a measurement of the hadronic shift and width of kaonic deuterium is necessary. Therefore, new X-ray studies with the focus on kaonic deuterium are in preparation (SIDDHARTA2. Many improvements in the experimental setup will allow to measure kaonic deuterium which is challenging due to the anticipated low X-ray yield. Especially important are the data on the X-ray yields of kaonic deuterium extracted from a exploratory experiment within SIDDHARTA.

  16. Provider of Services File

    Data.gov (United States)

    U.S. Department of Health & Human Services — The POS file consists of two data files, one for CLIA labs and one for 18 other provider types. The file names are CLIA and OTHER. If downloading the file, note it...

  17. What HERA may provide?

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hannes [DESY, Hamburg (Germany); De Roeck, Albert [CERN, Genf (Switzerland); Bartles, Jochen [Univ. Hamburg (DE). Institut fuer Theoretische Physik II] (and others)

    2008-09-15

    More than 100 people participated in a discussion session at the DIS08 workshop on the topic What HERA may provide. A summary of the discussion with a structured outlook and list of desirable measurements and theory calculations is given. (orig.)

  18. Relational Representations of Strongly Algebraic Lattices

    Institute of Scientific and Technical Information of China (English)

    XU Guang-hong; RAO San-ping

    2012-01-01

    In this paper,we introduce and investigate the strongly regular relation.Then we give the relational representations and an intrinsic characterization of strongly algebraic lattices via mapping relation and strongly regular relation.

  19. The strong maximum principle revisited

    Science.gov (United States)

    Pucci, Patrizia; Serrin, James

    In this paper we first present the classical maximum principle due to E. Hopf, together with an extended commentary and discussion of Hopf's paper. We emphasize the comparison technique invented by Hopf to prove this principle, which has since become a main mathematical tool for the study of second order elliptic partial differential equations and has generated an enormous number of important applications. While Hopf's principle is generally understood to apply to linear equations, it is in fact also crucial in nonlinear theories, such as those under consideration here. In particular, we shall treat and discuss recent generalizations of the strong maximum principle, and also the compact support principle, for the case of singular quasilinear elliptic differential inequalities, under generally weak assumptions on the quasilinear operators and the nonlinearities involved. Our principal interest is in necessary and sufficient conditions for the validity of both principles; in exposing and simplifying earlier proofs of corresponding results; and in extending the conclusions to wider classes of singular operators than previously considered. The results have unexpected ramifications for other problems, as will develop from the exposition, e.g. two point boundary value problems for singular quasilinear ordinary differential equations (Sections 3 and 4); the exterior Dirichlet boundary value problem (Section 5); the existence of dead cores and compact support solutions, i.e. dead cores at infinity (Section 7); Euler-Lagrange inequalities on a Riemannian manifold (Section 9); comparison and uniqueness theorems for solutions of singular quasilinear differential inequalities (Section 10). The case of p-regular elliptic inequalities is briefly considered in Section 11.

  20. Promoting Strong Written Communication Skills

    Science.gov (United States)

    Narayanan, M.

    2015-12-01

    The reason that an improvement in the quality of technical writing is still needed in the classroom is due to the fact that universities are facing challenging problems not only on the technological front but also on the socio-economic front. The universities are actively responding to the changes that are taking place in the global consumer marketplace. Obviously, there are numerous benefits of promoting strong written communication skills. They can be summarized into the following six categories. First, and perhaps the most important: The University achieves learner satisfaction. The learner has documented verbally, that the necessary knowledge has been successfully acquired. This results in learner loyalty that in turn will attract more qualified learners.Second, quality communication lowers the cost per pupil, consequently resulting in increased productivity backed by a stronger economic structure and forecast. Third, quality communications help to improve the cash flow and cash reserves of the university. Fourth, having high quality communication enables the university to justify the need for high costs of tuition and fees. Fifth, better quality in written communication skills result in attracting top-quality learners. This will lead to happier and satisfied learners, not to mention greater prosperity for the university as a whole. Sixth, quality written communication skills result in reduced complaints, thus meaning fewer hours spent on answering or correcting the situation. The University faculty and staff are thus able to devote more time on scholarly activities, meaningful research and productive community service. References Boyer, Ernest L. (1990). Scholarship reconsidered: Priorities of the Professorate.Princeton, NJ: Carnegie Foundation for the Advancement of Teaching. Hawkins, P., & Winter, J. (1997). Mastering change: Learning the lessons of the enterprise.London: Department for Education and Employment. Buzzel, Robert D., and Bradley T. Gale. (1987

  1. Internet Medline providers.

    Science.gov (United States)

    Vine, D L; Coady, T R

    1998-01-01

    Each database in this review has features that will appeal to some users. Each provides a credible interface to information available within the Medline database. The major differences are pricing and interface design. In this context, features that cost more and might seem trivial to the occasional searcher may actually save time and money when used by the professional. Internet Grateful Med is free, but Ms. Coady and I agree the availability of only three ANDable search fields is a major functional limitation. PubMed is also free but much more powerful. The command line interface that permits very sophisticated searches requires a commitment that casual users will find intimidating. Ms. Coady did not believe the feedback currently provided during a search was sufficient for sustained professional use. Paper Chase and Knowledge Finder are mature, modestly priced Medline search services. Paper Chase provides a menu-driven interface that is very easy to use, yet permits the user to search virtually all of Medline's data fields. Knowledge Finder emphasizes the use of natural language queries but fully supports more traditional search strategies. The impact of the tradeoff between fuzzy and Boolean strategies offered by Knowledge Finder is unclear and beyond the scope of this review. Additional software must be downloaded to use all of Knowledge Finders' features. Other providers required no software beyond the basic Internet browser, and this requirement prevented Ms. Coady from evaluating Knowledge Finder. Ovid and Silver Platter offer well-designed interfaces that simplify the construction of complex queries. These are clearly services designed for professional users. While pricing eliminates these for casual use, it should be emphasized that Medline citation access is only a portion of the service provided by these high-end vendors. Finally, we should comment that each of the vendors and government-sponsored services provided prompt and useful feedback to e

  2. <strong>Compositional specification of commercial contractsstrong>

    DEFF Research Database (Denmark)

    Andersen, Jesper; Elsborg, Ebbe; Henglein, Fritz

    2006-01-01

    amongst multiple parties and complements McCarthy’s Resources, Events and Agents (REA) accounting model (McCarthy in Account Rev. LVII(3), 554–578, 1982) with a view- independent formal contract model that supports definition of user-defined contracts, automatic monitoring under execution and user......-definable analysis of their state before, during and after execution. We provide several realistic examples of commercial contracts and their analyses. A variety of (real) contracts can be expressed in such a fashion as to support their integration, management and analysis in an operational environment...... that registers events. The language design is driven by both domain considerations and semantic language design methods: a contract denotes a set of traces of events, each of which is an alternative way of concluding the contract successfully, which gives rise to a CSP-style (Brooker et al. in J.ACM 31(3), 560...

  3. A comparison of two patch NAH methods<strong> strong>

    DEFF Research Database (Denmark)

    Gomes, Jesper Skovhus; Hald, Jørgen

    continuation of the measured pressure beyond the measurement area, followed by the use of standard NAH procedures. Two other methods completely avoid the use of spatial FFT, and instead they perform a least squares fit of a local sound field model to the measured sound pressure data. Statistically Optimized......The spatial FFT processing used in Near-field Acoustical Holography (NAH) makes the method computationally efficient, but it introduces severe spatial windowing effects, unless the measurement area is significantly larger than the source. To avoid the need for these very extended measurement areas......, Patch Holography techniques have been developed to provide acceptable accuracy based on measurements that only partially cover the source area. Calculation and mapping is then performed over a corresponding concentric patch, typically on the source surface. One such method performs an iterative analytic...

  4. Efimov correlations in strongly interacting Bose gases

    Science.gov (United States)

    Hofmann, Johannes; Barth, Marcus

    A series of recent hallmark experiments have demonstrated that Bose gases can be created in the strongly interacting unitary limit in the non-degenerate high-temperature regime. These systems display the three-body Efimov effect, which poses a theoretical challenge to compute observables including these relevant three-body correlations. In this talk, I shall present our results for the virial coefficients, the contact parameters, and the momentum distribution of a strongly interacting three-dimensional Bose gas obtained by means of a virial expansion up to third order in the fugacity, which takes into account three-body correlations exactly. Our results characterize the non-degenerate regime of the interacting Bose gas, where the thermal wavelength is smaller than the interparticle spacing but the scattering length may be arbitrarily large. In addition, we provide a calculation of the momentum distribution at unitarity, which displays a universal high-momentum tail with a log-periodic momentum dependence - a direct signature of Efimov physics. In particular, we provide a quantitative description of the momentum distribution at high momentum as measured by the JILA group [Makotyn et al., Nat. Phys. 10, 116 (2014)]. Our results allow the spectroscopy of Efimov states at unitarity.

  5. Building Service Provider Capabilities

    DEFF Research Database (Denmark)

    Brandl, Kristin; Jaura, Manya; Ørberg Jensen, Peter D.

    In this paper we study whether and how the interaction between clients and the service providers contributes to the development of capabilities in service provider firms. In situations where such a contribution occurs, we analyze how different types of activities in the production process...... of the services, such as sequential or reciprocal task activities, influence the development of different types of capabilities. We study five cases of offshore-outsourced knowledge-intensive business services that are distinguished according to their reciprocal or sequential task activities in their production...... process. We find that clients influence the development of human capital capabilities and management capabilities in reciprocally produced services. While in sequential produced services clients influence the development of organizational capital capabilities and management capital capabilities....

  6. Achieving Provider Engagement

    Science.gov (United States)

    Greenfield, Geva; Pappas, Yannis; Car, Josip; Majeed, Azeem; Harris, Matthew

    2014-01-01

    The literature on integrated care is limited with respect to practical learning and experience. Although some attention has been paid to organizational processes and structures, not enough is paid to people, relationships, and the importance of these in bringing about integration. Little is known, for example, about provider engagement in the organizational change process, how to obtain and maintain it, and how it is demonstrated in the delivery of integrated care. Based on qualitative data from the evaluation of a large-scale integrated care initiative in London, United Kingdom, we explored the role of provider engagement in effective integration of services. Using thematic analysis, we identified an evolving engagement narrative with three distinct phases: enthusiasm, antipathy, and ambivalence, and argue that health care managers need to be aware of the impact of professional engagement to succeed in advancing the integrated care agenda. PMID:25212855

  7. Strong correlations in bosons and fermions

    Science.gov (United States)

    Tilahun, Dagim

    If there is a general theme to this thesis, it is the effects of strong correlations in both bosons and fermions. The bosonic system considered here consists of ultracold alkali atoms trapped by interfering lasers, so called optical lattices. Strong interactions, realized by increasing the depth of the lattice potential, or through the phenomenon of Feshbach resonances induce strong correlations amongst the atoms, rendering attempts to describe the systems in terms of single particle type physics unsuccessful. Of course strong correlations are not the exclusive domain of bosons, and also are not caused only by strong interactions. Other factors such as reduced dimensionality, in one-dimensional electron gases, or strong magnetic fields, in two-dimensional electron gases are known to induce strong correlations. In this thesis, we explore the manifestations of strong correlations in ultracold atoms in optical lattices and interacting electron gases. Optical lattices provide a near-perfect realization of lattice models, such as the bosonic Hubbard model (BHM) that have been formulated to study solid state systems. This follows from the absence of defects or impurities that usually plague real solid state systems. Another novel feature of optical lattices is the unprecedented control experimenters have in tuning the different lattice parameters, such as the lattice spacing and the intensity of the lasers. This control enables one to study the model Hamiltonians over a wide range of variables, such as the interaction strength between the atoms, thereby opening the door towards the observation of diverse and interesting phenomena. The BHM, and also its variants, predict various quantum phases, such as the strongly correlated Mott insulator (MI) phase that appears as a function of the parameter t/U, the ratio of the nearest neighbor hopping amplitude to the on-site interaction, which one varies experimentally over a wide range of values simply by switching the intensity

  8. Providing Compassion through Flow

    Directory of Open Access Journals (Sweden)

    Lydia Royeen

    2015-07-01

    Full Text Available Meg Kral, MS, OTR/L, CLT, is the cover artist for the Summer 2015 issue of The Open Journal of Occupational Therapy. Her untitled piece of art is an oil painting and is a re-creation of a photograph taken while on vacation. Meg is currently supervisor of outpatient services at Rush University Medical Center. She is lymphedema certified and has a specific interest in breast cancer lymphedema. Art and occupational therapy serve similar purposes for Meg: both provide a sense of flow. She values the outcomes, whether it is a piece of art or improved functional status

  9. Strong Completeness of Medium Logic System

    Institute of Scientific and Technical Information of China (English)

    Pan Zhenghua; Zhu Wujia

    2005-01-01

    The strong completeness of medium logic system is discussed. The following results are proved: medium propositional logic system MP and its extension MP * are strong complete; medium predicate logic system MF and its extensions ( MF * and ME * ) are not strong complete; and generally, if a consistent formal system is not strong complete, then any consistent extensions of this formai system are not strong complete either.

  10. Nickel: makes stainless steel strong

    Science.gov (United States)

    Boland, Maeve A.

    2012-01-01

    Nickel is a silvery-white metal that is used mainly to make stainless steel and other alloys stronger and better able to withstand extreme temperatures and corrosive environments. Nickel was first identified as a unique element in 1751 by Baron Axel Fredrik Cronstedt, a Swedish mineralogist and chemist. He originally called the element kupfernickel because it was found in rock that looked like copper (kupfer) ore and because miners thought that "bad spirits" (nickel) in the rock were making it difficult for them to extract copper from it. Approximately 80 percent of the primary (not recycled) nickel consumed in the United States in 2011 was used in alloys, such as stainless steel and superalloys. Because nickel increases an alloy's resistance to corrosion and its ability to withstand extreme temperatures, equipment and parts made of nickel-bearing alloys are often used in harsh environments, such as those in chemical plants, petroleum refineries, jet engines, power generation facilities, and offshore installations. Medical equipment, cookware, and cutlery are often made of stainless steel because it is easy to clean and sterilize. All U.S. circulating coins except the penny are made of alloys that contain nickel. Nickel alloys are increasingly being used in making rechargeable batteries for portable computers, power tools, and hybrid and electric vehicles. Nickel is also plated onto such items as bathroom fixtures to reduce corrosion and provide an attractive finish.

  11. What HERA May Provide?

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Hannes; /DESY; De Roeck, Albert; /CERN; Bartels, Jochen; /Hamburg U., Inst. Theor. Phys. II; Behnke, Olaf; Blumlein, Johannes; /DESY; Brodsky, Stanley; /SLAC /Durham U., IPPP; Cooper-Sarkar, Amanda; /Oxford U.; Deak, Michal; /DESY; Devenish, Robin; /Oxford U.; Diehl, Markus; /DESY; Gehrmann, Thomas; /Zurich U.; Grindhammer, Guenter; /Munich, Max Planck Inst.; Gustafson, Gosta; /CERN /Lund U., Dept. Theor. Phys.; Khoze, Valery; /Durham U., IPPP; Knutsson, Albert; /DESY; Klein, Max; /Liverpool U.; Krauss, Frank; /Durham U., IPPP; Kutak, Krzysztof; /DESY; Laenen, Eric; /NIKHEF, Amsterdam; Lonnblad, Leif; /Lund U., Dept. Theor. Phys.; Motyka, Leszek; /Hamburg U., Inst. Theor. Phys. II /Birmingham U. /Southern Methodist U. /DESY /Piemonte Orientale U., Novara /CERN /Paris, LPTHE /Hamburg U. /Penn State U.

    2011-11-10

    More than 100 people participated in a discussion session at the DIS08 workshop on the topic What HERA may provide. A summary of the discussion with a structured outlook and list of desirable measurements and theory calculations is given. The HERA accelerator and the HERA experiments H1, HERMES and ZEUS stopped running in the end of June 2007. This was after 15 years of very successful operation since the first collisions in 1992. A total luminosity of {approx} 500 pb{sup -1} has been accumulated by each of the collider experiments H1 and ZEUS. During the years the increasingly better understood and upgraded detectors and HERA accelerator have contributed significantly to this success. The physics program remains in full swing and plenty of new results were presented at DIS08 which are approaching the anticipated final precision, fulfilling and exceeding the physics plans and the previsions of the upgrade program. Most of the analyses presented at DIS08 were still based on the so called HERA I data sample, i.e. data taken until 2000, before the shutdown for the luminosity upgrade. This sample has an integrated luminosity of {approx} 100 pb{sup -1}, and the four times larger statistics sample from HERA II is still in the process of being analyzed.

  12. Strong interaction physics from hadronic atoms

    Science.gov (United States)

    Batty, C. J.; Friedman, E.; Gal, A.

    1997-08-01

    Hadronic atoms provide a unique laboratory for studying strong interactions and nuclear medium effects at zero kinetic energy. Previous results from analyses of strong-interaction data consisting of level shifts, widths and yields in π-, K -, p¯ and ∑ - atoms are reviewed. Recent results from fits to comprehensive sets of data in terms of density-dependent optical potentials that respect the low-density limit, where the interaction tends to the free hadron nucleon value, are discussed. The importance of using realistic nuclear density distributions is highlighted. The introduction of density dependence in most cases significantly improves the fit to the data and leads to some novel results. For K - atoms, a substantial attraction of order 200 MeV in nuclear matter is suggested, with interesting repercussions for K¯ condensation and the evolution of strangeness in high-density stars. For p¯ atoms it is found that a reasonable p-wave strength can be accommodated in the fitted optical potential, in agreement with the energy dependence observed for some low-energy p¯N reactions. For ∑ - atoms, the fitted potential becomes repulsive inside the nucleus, implying that Σ hyperons generally do not bind in nuclei in agreement with recent measurements. This repulsion significantly affects calculated masses of neutron stars.

  13. Spectroscopic Imaging of Strongly Correlated Electronic States

    Science.gov (United States)

    Yazdani, Ali; da Silva Neto, Eduardo H.; Aynajian, Pegor

    2016-03-01

    The study of correlated electronic systems from high-Tc cuprates to heavy-fermion systems continues to motivate the development of experimental tools to probe electronic phenomena in new ways and with increasing precision. In the past two decades, spectroscopic imaging with scanning tunneling microscopy has emerged as a powerful experimental technique. The combination of high energy and spatial resolutions provided by this technique reveals unprecedented detail of the electronic properties of strongly correlated metals and superconductors. This review examines specific experiments, theoretical concepts, and measurement methods that have established the application of these techniques to correlated materials. A wide range of applications, such as the study of collective responses to single atomic impurities, the characterization of quasiparticle-like excitations through their interference, and the identification of competing electronic phases using spectroscopic imaging, are discussed.

  14. Footprints of New Strong Dynamics via Anomaly

    CERN Document Server

    Nakai, Yuichiro; Tobioka, Kohsaku

    2015-01-01

    Chiral anomaly provides a smoking-gun evidence of a new confining gauge theory. Motivated by a reported event excess in diphoton invariant mass distribution at the LHC, we discuss a scenario that a pseudo-Nambu-Goldstone (pNG) boson of a new QCD-like theory is produced by gluon fusion and decays into a pair of the standard model gauge bosons. Despite the strong dynamics, the production cross section and the decay widths are determined by anomaly matching condition. The excess can be explained by the pNG boson with mass of around 750 GeV. The model also predicts exotic hadrons such as a color octet scalar and baryons which are within the reach of the LHC experiment.

  15. Inherent enumerability of strong jump-traceability

    CERN Document Server

    Diamondstone, David; Turetsky, Daniel

    2011-01-01

    We show that every strongly jump-traceable set obeys every benign cost function. Moreover, we show that every strongly jump-traceable set is computable from a computably enumerable strongly jump-traceable set. This allows us to generalise properties of c.e.\\ strongly jump-traceable sets to all such sets. For example, the strongly jump-traceable sets induce an ideal in the Turing degrees; the strongly jump-traceable sets are precisely those that are computable from all superlow Martin-L\\"{o}f random sets; the strongly jump-traceable sets are precisely those that are a base for $\\text{Demuth}_{\\text{BLR}}$-randomness; and strong jump-traceability is equivalent to strong superlowness.

  16. Discovering Classes of Strongly Equivalent Logic Programs

    OpenAIRE

    Chen, Y.; Lin, F.

    2011-01-01

    In this paper we apply computer-aided theorem discovery technique to discover theorems about strongly equivalent logic programs under the answer set semantics. Our discovered theorems capture new classes of strongly equivalent logic programs that can lead to new program simplification rules that preserve strong equivalence. Specifically, with the help of computers, we discovered exact conditions that capture the strong equivalence between a rule and the empty set, between two rules, between t...

  17. Strong reality of finite simple groups

    CERN Document Server

    Vdovin, E P

    2010-01-01

    The classification of finite simple strongly real groups is complete. It is easy to see that strong reality for every nonabelian finite simple group is equivalent to the fact that each element can be written as a product of two involutions. We thus obtain a solution to Problem 14.82 from the Kourovka notebook from the classification of finite simple strongly real groups.

  18. Strong Bisimilarity of Simple Process Algebras

    DEFF Research Database (Denmark)

    Srba, Jirí

    2003-01-01

    We study bisimilarity and regularity problems of simple process algebras. In particular, we show PSPACE-hardness of the following problems: (i) strong bisimilarity of Basic Parallel Processes (BPP), (ii) strong bisimilarity of Basic Process Algebra (BPA), (iii) strong regularity of BPP, and (iv) ...

  19. Strong decays of baryons and missing resonances

    Science.gov (United States)

    Bijker, R.; Ferretti, J.; Galatà, G.; García-Tecocoatzi, H.; Santopinto, E.

    2016-10-01

    We provide results for the open-flavor strong decays of strange and nonstrange baryons into a baryon-vector/pseudoscalar meson pair. The decay amplitudes are computed in the 3P0 pair-creation model, where s s ¯ pair-creation suppression is included for the first time in the baryon sector, in combination with the U (7 ) and hypercentral models. The effects of this s s ¯ suppression mechanism cannot be reabsorbed in a redefinition of the model parameters or in a different choice of the 3P0 model vertex factor. Our results for the decay amplitudes are compared with the existing experimental data and previous 3P0 and elementary meson emission model calculations. In this respect, we show that distinct quark models differ in the number of missing resonances they predict and also in the quantum numbers of states. Therefore, future experimental results will be important in order to disentangle different models of baryon structure. Finally, in the appendixes, we provide some details of our calculations, including the derivation of all relevant flavor couplings with strangeness suppression. This derivation may be helpful to calculate the open-flavor decay amplitudes starting from other models of baryons.

  20. Strong Bisimilarity of Simple Process Algebras

    DEFF Research Database (Denmark)

    Srba, Jirí

    2003-01-01

    We study bisimilarity and regularity problems of simple process algebras. In particular, we show PSPACE-hardness of the following problems: (i) strong bisimilarity of Basic Parallel Processes (BPP), (ii) strong bisimilarity of Basic Process Algebra (BPA), (iii) strong regularity of BPP, and (iv......) strong regularity of BPA. We also demonstrate NL-hardness of strong regularity problems for the normed subclasses of BPP and BPA. Bisimilarity problems of simple process algebras are introduced in a general framework of process rewrite systems, and a uniform description of the new techniques used...

  1. Bodrum Strong Motion Network, Mugla, Turkey

    Science.gov (United States)

    Alcik, H. A.; Tanircan, G.; Korkmaz, A.

    2015-12-01

    The Gulf of Gökova is located in southwestern Turkey near the Aegean Sea and surrounded by Datça Peninsula to the south, the island of Kos to the west and Bodrum Peninsula to the north. The Bodrum peninsula with a population of one million in summer season is one of the most populated touristic centers of Turkey. This region is also surrounded by numerous active seismic entities such as Ula-Ören Fault Zone, Gökova Graben etc.. and demonstrates high seismic hazard. In the past, many destructive earthquakes have occurred in southwestern Turkey. One of the destructive historical earthquakes is 1493 Kos event (Mw=6.9) caused heavy damage in Bodrum. In the instrumental period seismic activity in the Gökova region includes the Ms>6.0 earthquakes of 23 April 1933 (Ms=6.4), 23 May 1941 (Ms=6.0), 13 December 1941 (Ms=6.5) events. Intense earthquake activity (Mw5+) occurred in Gulf of Gökova in August 2004 and January 2005. Considering the high seismicity and population of this region, a strong ground motion monitoring system stationed in dense settlements in the Bodrum Peninsula: Bodrum, Turgutreis, Yalıkavak, Çiftlik and Ortakent was deployed on June 2015. The network consists of 5 strong motion recorders, has been set up with the aim of monitoring of regional earthquakes, collecting accurate and reliable data for engineering and scientific research purposes, in particular to provide input for future earthquake rapid reporting and early warning implementation projects on urban environments in the Bodrum peninsula and the surrounding areas. In this poster presentation, we briefly introduce the Bodrum Network and discuss our future plans for further developments.

  2. Energy Method to Obtain Approximate Solutions of Strongly Nonlinear Oscillators

    Directory of Open Access Journals (Sweden)

    Alex Elías-Zúñiga

    2013-01-01

    Full Text Available We introduce a nonlinearization procedure that replaces the system potential energy by an equivalent representation form that is used to derive analytical solutions of strongly nonlinear conservative oscillators. We illustrate the applicability of this method by finding the approximate solutions of two strongly nonlinear oscillators and show that this procedure provides solutions that follow well the numerical integration solutions of the corresponding equations of motion.

  3. Strongly Irreducible Operators on Banach Spaces

    Institute of Scientific and Technical Information of China (English)

    Yun Nan ZHANG; Huai Jie ZHONG

    2012-01-01

    This paper firstly discusses the existence of strongly irreducible operators on Banach spaces.It shows that there exist strongly irreducible operators on Banach spaces with w*-separable dual.It also gives some properties of strongly irreducible operators on Banach spaces. In particular,if T is a strongly irreducible operator on an infinite-dimensional Banach space,then T is not of finite rank and T is not an algebraic operator. On Banach spaces with subsymmetric bases,including infinite-dimensional separable Hilbert spaces,it shows that quasisimilarity does not preserve strong irreducibility.In addition,we show that the strong irreducibility of an operator does not imply the strong irreducibility of its conjugate operator,which is not the same as the property in Hilbert spaces.

  4. Nonlinear magnetoplasmons in strongly coupled Yukawa plasmas

    CERN Document Server

    Bonitz, M; Ott, T; Kaehlert, H; Hartmann, P

    2010-01-01

    The existence of plasma oscillations at multiples of the magnetoplasmon frequency in a strongly coupled two-dimensional magnetized Yukawa plasma is reported, based on extensive molecular dynamics simulations. These modes are the analogues of Bernstein modes which are renormalized by strong interparticle correlations. Their properties are theoretically explained by a dielectric function incorporating the combined effect of a magnetic field, strong correlations and finite temperature.

  5. Nanoscale electrodynamics of strongly correlated quantum materials

    Science.gov (United States)

    Liu, Mengkun; Sternbach, Aaron J.; Basov, D. N.

    2017-01-01

    Electronic, magnetic, and structural phase inhomogeneities are ubiquitous in strongly correlated quantum materials. The characteristic length scales of the phase inhomogeneities can range from atomic to mesoscopic, depending on their microscopic origins as well as various sample dependent factors. Therefore, progress with the understanding of correlated phenomena critically depends on the experimental techniques suitable to provide appropriate spatial resolution. This requirement is difficult to meet for some of the most informative methods in condensed matter physics, including infrared and optical spectroscopy. Yet, recent developments in near-field optics and imaging enabled a detailed characterization of the electromagnetic response with a spatial resolution down to 10 nm. Thus it is now feasible to exploit at the nanoscale well-established capabilities of optical methods for characterization of electronic processes and lattice dynamics in diverse classes of correlated quantum systems. This review offers a concise description of the state-of-the-art near-field techniques applied to prototypical correlated quantum materials. We also discuss complementary microscopic and spectroscopic methods which reveal important mesoscopic dynamics of quantum materials at different energy scales.

  6. Estimating strong correlations in optical lattices

    Science.gov (United States)

    Gertis, J.; Friesdorf, M.; Riofrío, C. A.; Eisert, J.

    2016-11-01

    Ultracold atoms in optical lattices provide one of the most promising platforms for analog quantum simulations of complex quantum many-body systems. Large-size systems can now routinely be reached and are already used to probe a large variety of different physical situations, ranging from quantum phase transitions to artificial gauge theories. At the same time, measurement techniques are still limited and full tomography for these systems seems out of reach. Motivated by this observation, we present a method to directly detect and quantify to what extent a quantum state deviates from a local Gaussian description, based on available noise correlation measurements from in situ and time-of-flight measurements. This is an indicator of the significance of strong correlations in ground and thermal states, as Gaussian states are precisely the ground and thermal states of noninteracting models. We connect our findings, augmented by numerical tensor network simulations, to notions of equilibration, disordered systems, and the suppression of transport in Anderson insulators.

  7. EXISTENCE OF OPTIMAL STRONG PARTIALLY BALANCED DESIGNS

    Institute of Scientific and Technical Information of China (English)

    Du Beiliang

    2007-01-01

    A strong partially balanced design SPBD(v, b, k; λ,0) whose b is the maximum number of blocks in all SPBD(v, b, k; λ, 0), as an optimal strong partially balanced design, briefly OSPBD(v, k, λ) is studied. In investigation of authentication codes it has been found that the strong partially balanced design can be used to construct authentication codes. This note investigates the existence of optimal strong partially balanced design OSPBD(v, k, 1) for k = 3and 4, and shows that there exists an OSPBD(v, k, 1) for any v ≥ k.

  8. Strong decays of nucleon and $\\Delta$ resonances

    CERN Document Server

    Bijker, R

    1996-01-01

    We study the strong couplings of the nucleon and delta resonances in a collective model. In the ensuing algebraic treatment we derive closed expressions for decay widths which are used to analyze the experimental data for strong decays into the pion and eta channels.

  9. Theoretical studies of strongly correlated fermions

    Energy Technology Data Exchange (ETDEWEB)

    Logan, D. [Institut Max von Laue - Paul Langevin (ILL), 38 - Grenoble (France)

    1997-04-01

    Strongly correlated fermions are investigated. An understanding of strongly correlated fermions underpins a diverse range of phenomena such as metal-insulator transitions, high-temperature superconductivity, magnetic impurity problems and the properties of heavy-fermion systems, in all of which local moments play an important role. (author).

  10. Strong monotonicity for analytic ordinary differential equations

    Directory of Open Access Journals (Sweden)

    Sebastian Walcher

    2009-09-01

    Full Text Available We present a necessary and sufficient criterion for the flow of an analytic ordinary differential equation to be strongly monotone; equivalently, strongly order-preserving. The criterion is given in terms of the reducibility set of the derivative of the right-hand side. Some applications to systems relevant in biology and ecology, including nonlinear compartmental systems, are discussed.

  11. Strong Connections and Invertible Weak Entwining Structures

    Institute of Scientific and Technical Information of China (English)

    J.N.ALONSO (A)LVAREZ; J.M.FERN(A)NDEZ VILABOA; R.GONZ(A)LEZ RODR(I)GUEZ

    2012-01-01

    In this paper we obtain a criterion under which the bijectivity of the canonical morphism of a weak Galois extension associated to a weak invertible entwining structure is equivalent to the existence of a strong connection form.Also we obtain an explicit formula for a strong connection under equivariant projective conditions or under coseparability conditions.

  12. 78 FR 15710 - Strong Sensitizer Guidance

    Science.gov (United States)

    2013-03-12

    ... document is intended to clarify the ``strong sensitizer'' definition, assist manufacturers in understanding.... Consumer Product Safety Commission, 5 Research Place, Rockville, MD 20850; telephone (301) 987-2564... definition of ``strong sensitizer'' found at 16 CFR 1500.3(c)(5). The Commission is proposing to revise...

  13. On the Strong Direct Summand Conjecture

    Science.gov (United States)

    McCullough, Jason

    2009-01-01

    In this thesis, our aim is the study the Vanishing of Maps of Tor Conjecture of Hochster and Huneke. We mainly focus on an equivalent characterization called the Strong Direct Summand Conjecture, due to N. Ranganathan. Our results are separated into three chapters. In Chapter 3, we prove special cases of the Strong Direct Summand Conjecture in…

  14. Strong jump traceability and Demuth randomness

    CERN Document Server

    Greenberg, Noam

    2011-01-01

    We solve the covering problem for Demuth randomness, showing that a computably enumerable set is computable from a Demuth random set if and only if it is strongly jump-traceable. We show that on the other hand, the class of sets which form a base for Demuth randomness is a proper subclass of the class of strongly jump-traceable sets.

  15. About strong interaction of fundamental particles

    CERN Document Server

    Sannikov-Proskuryakov, S S

    2002-01-01

    We concentrate upon the main properties of strong interaction of hadrons. It is demonstrated that, due to the unusual character of the field propagator in a fiber (at very small distances) where strong interaction is switched on, a new symmetric Green function is used as a field propagator. As a result, the unitary scattering matrix of strong interaction is represented as a T sub s -time ordered chronological exponent. It is shown that the particle skeleton algebra plays an important role in finding the full interaction Lagrangian. Coupling constants of strong interactions are determined. In Appendix, the radiative corrections to the nucleon mass and the masses of eta, pi, KAPPA mesons transferring the strong interactions are calculated.

  16. Internet Provider Facilities, Published in Not Provided, US Army.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Internet Provider Facilities dataset as of Not Provided. Data by this publisher are often provided in Not Applicable coordinate system; in a Not Applicable...

  17. The predominance of strong initial syllables in the English vocabulary

    NARCIS (Netherlands)

    Cutler, A.; Carter, D.M.

    1987-01-01

    Studies of human speech processing have provided evidece for a segmentation strategy in the perception of continuous speech, whereby a word boundary is postulated, and a lexical access procedure initiated, at each metrically strong syllable. The likely success of this strategy was here estimated aga

  18. Strong Duality and Optimality Conditions for Generalized Equilibrium Problems

    Directory of Open Access Journals (Sweden)

    D. H. Fang

    2013-01-01

    Full Text Available We consider a generalized equilibrium problem involving DC functions. By using the properties of the epigraph of the conjugate functions, some sufficient and/or necessary conditions for the weak and strong duality results and optimality conditions for generalized equilibrium problems are provided.

  19. SPHYNX: SPH hydrocode for subsonic hydrodynamical instabilities and strong shocks

    Science.gov (United States)

    Cabezon, Ruben M.; Garcia-Senz, Domingo

    2017-09-01

    SPHYNX addresses subsonic hydrodynamical instabilities and strong shocks; it is Newtonian, grounded on the Euler-Lagrange formulation of the smoothed-particle hydrodynamics technique, and density based. SPHYNX uses an integral approach for estimating gradients, a flexible family of interpolators to suppress pairing instability, and incorporates volume elements to provides better partition of the unity.

  20. Semi-strong split domination in graphs

    Directory of Open Access Journals (Sweden)

    Anwar Alwardi

    2014-06-01

    Full Text Available Given a graph $G = (V,E$, a dominating set $D subseteq V$ is called a semi-strong split dominating set of $G$ if $|V setminus D| geq 1$ and the maximum degree of the subgraph induced by $V setminus D$ is 1. The minimum cardinality of a semi-strong split dominating set (SSSDS of G is the semi-strong split domination number of G, denoted $gamma_{sss}(G$. In this work, we introduce the concept and prove several results regarding it.

  1. Strong and superstrong pulsed magnetic fields generation

    CERN Document Server

    Shneerson, German A; Krivosheev, Sergey I

    2014-01-01

    Strong pulsed magnetic fields are important for several fields in physics and engineering, such as power generation and accelerator facilities. Basic aspects of the generation of strong and superstrong pulsed magnetic fields technique are given, including the physics and hydrodynamics of the conductors interacting with the field as well as an account of the significant progress in generation of strong magnetic fields using the magnetic accumulation technique. Results of computer simulations as well as a survey of available field technology are completing the volume.

  2. The lambda sigma calculus and strong normalization

    DEFF Research Database (Denmark)

    Schack-Nielsen, Anders; Schürmann, Carsten

    Explicit substitution calculi can be classified into several dis- tinct categories depending on whether they are confluent, meta-confluent, strong normalization preserving, strongly normalizing, simulating, fully compositional, and/or local. In this paper we present a variant of the λσ-calculus......, which satisfies all seven conditions. In particular, we show how to circumvent Mellies counter-example to strong normalization by a slight restriction of the congruence rules. The calculus is implemented as the core data structure of the Celf logical framework. All meta-theoretic aspects of this work...

  3. Strong photoassociation in a degenerate fermi gas

    Science.gov (United States)

    Rvachov, Timur; Jamison, Alan; Jing, Li; Son, Hyungmok; Ebadi, Sepehr; Jiang, Yijun; Zwierlein, Martin; Ketterle, Wolfgang

    2016-05-01

    Despite many studies there remain open questions about strong photoassociation in ultracold gases. We study the effects of strong photoassociation in ultracold fermions. Photoassociation occurs only at short range and thus can be used as a tool to probe and control the two-body correlation function in an interacting many-body system. We study the effects of strong photoassociation in 6 Li, the onset of saturation, and its effects on spin polarized and interacting spin-mixtures. This work was funded by the NSF, ARO-MURI, SAMSUNG, and NSERC.

  4. Generalized Strongly Nonlinear Implicit Quasivariational Inequalities

    Directory of Open Access Journals (Sweden)

    Salahuddin  

    2009-01-01

    Full Text Available We prove an existence theorem for solution of generalized strongly nonlinear implicit quasivariational inequality problems and convergence of iterative sequences with errors, involving Lipschitz continuous, generalized pseudocontractive and generalized -pseudocontractive mappings in Hilbert spaces.

  5. From individual to strongly coupled metallic nanocavities

    CERN Document Server

    Salomon, Adi; Kolkowski, Radoslaw; Zyss, Joseph

    2013-01-01

    Localized plasmonic modes of metallic nanoparticles may hybridize like those of atoms forming a molecule. However, the rapid decay of the plasmonic fields outside the metal severely limits the range of these interactions to tens of nanometers. Herein, we demonstrate very strong coupling of nanocavities in metal films, sparked by propagating surface plasmons and evident even at much larger distances of hundreds of nanometers for the properly selected metal/wavelength combination. Such strong coupling drastically changes the symmetry of the charge distribution around the nanocavities making it amenable to probing by the nonlinear optical response of the medium. We show that when strongly coupled, equilateral triangular nanocavities lose their individual three-fold symmetry to adopt the lower symmetry of the coupled system and then respond like a single dipolar entity. A quantitative model is suggested for the transition from individual to strongly coupled nanocavities.

  6. Green jobs and a strong middle class.

    Science.gov (United States)

    Podesta, John D

    2009-01-01

    Green jobs are critical to building a strong middle class, and millions of green jobs can be created through energy efficiency. The models already exist for this work, but we need sustained investment to bring them to scale.

  7. Probing Strong Field Gravity Through Numerical Simulations

    CERN Document Server

    Choptuik, Matthew W; Pretorius, Frans

    2015-01-01

    This article is an overview of the contributions numerical relativity has made to our understanding of strong field gravity, to be published in the book "General Relativity and Gravitation: A Centennial Perspective", commemorating the 100th anniversary of general relativity.

  8. Strong-force theorists scoop Noble Prize

    CERN Multimedia

    Durrani, Matin

    2004-01-01

    Three US theorists have shared the 2004 Nobel Prize in Physics "for the discovery of asymptotic freedom in the theory of the strong interaction". Their theoretical work explains why quarks behave almost as free particles at high energies (½ page)

  9. Conforming finite elements with embedded strong discontinuities

    NARCIS (Netherlands)

    Dias-da-Costa, D.; Alfaiate, J.; Sluys, L.J.; Areias, P.; Fernandes, C.; Julio, E.

    2012-01-01

    The possibility of embedding strong discontinuities into finite elements allowed the simulation of different problems, namely, brickwork masonry fracture, dynamic fracture, failure in finite strain problems and simulation of reinforcement concrete members. However, despite the significant contributi

  10. Strongly magnetized accretion discs require poloidal flux

    Science.gov (United States)

    Salvesen, Greg; Armitage, Philip J.; Simon, Jacob B.; Begelman, Mitchell C.

    2016-08-01

    Motivated by indirect observational evidence for strongly magnetized accretion discs around black holes, and the novel theoretical properties of such solutions, we investigate how a strong magnetization state can develop and persist. To this end, we perform local simulations of accretion discs with an initially purely toroidal magnetic field of equipartition strength. We demonstrate that discs with zero net vertical magnetic flux and realistic boundary conditions cannot sustain a strong toroidal field. However, a magnetic pressure-dominated disc can form from an initial configuration with a sufficient amount of net vertical flux and realistic boundary conditions. Our results suggest that poloidal flux is a necessary prerequisite for the sustainability of strongly magnetized accretion discs.

  11. Strongly magnetized accretion discs require poloidal flux

    CERN Document Server

    Salvesen, Greg; Simon, Jacob B; Begelman, Mitchell C

    2016-01-01

    Motivated by indirect observational evidence for strongly magnetized accretion discs around black holes, and the novel theoretical properties of such solutions, we investigate how a strong magnetization state can develop and persist. To this end, we perform local simulations of accretion discs with an initially purely toroidal magnetic field of equipartition strength. We demonstrate that discs with zero net vertical magnetic flux and realistic boundary conditions cannot sustain a strong toroidal field. However, a magnetic pressure-dominated disc can form from an initial configuration with a sufficient amount of net vertical flux and realistic boundary conditions. Our results suggest that poloidal flux is a necessary prerequisite for the sustainability of strongly magnetized accretion discs.

  12. Diffusive Mixing in Strongly Coupled Plasmas

    Science.gov (United States)

    Diaw, Abdourahmane; Murillo, Michael

    2016-10-01

    A multispecies hydrodynamic model based on moments of the Born-Bogolyubov-Green-Kirkwood-Yvon (BBGKY) hierarchy is developed for physical conditions relevant to astrophysical plasmas. The modified transport equations incorporate strong correlations through a density functional theory closure, while fluctuations enters through a mixture BGK operator. This model extends the usual Burgers equations for a dilute gas to strongly coupled and isothermal plasmas mixtures. The diffusive currents for these strongly coupled plasmas is self-consistently derived. The settling of impurities and its impact on cooling of white dwarfs and neutron stars can be greatly affected by strong Coulomb coupling, which we show can be quantified using the direct-correlation function. This work was supported by the Air Force Office of Scientific Research (Grant No. FA9550-12-1-0344).

  13. Strongly correlated electrostatics of viral genome packaging.

    Science.gov (United States)

    Nguyen, Toan T

    2013-03-01

    The problem of viral packaging (condensation) and ejection from viral capsid in the presence of multivalent counterions is considered. Experiments show divalent counterions strongly influence the amount of DNA ejected from bacteriophage. In this paper, the strong electrostatic interactions between DNA molecules in the presence of multivalent counterions is investigated. It is shown that experiment results agree reasonably well with the phenomenon of DNA reentrant condensation. This phenomenon is known to cause DNA condensation in the presence of tri- or tetra-valent counterions. For divalent counterions, the viral capsid confinement strongly suppresses DNA configurational entropy, therefore the correlation between divalent counterions is strongly enhanced causing similar effect. Computational studies also agree well with theoretical calculations.

  14. Strong Completeness of Coalgebraic Modal Logics

    CERN Document Server

    Schröder, Lutz

    2009-01-01

    Canonical models are of central importance in modal logic, in particular as they witness strong completeness and hence compactness. While the canonical model construction is well understood for Kripke semantics, non-normal modal logics often present subtle difficulties - up to the point that canonical models may fail to exist, as is the case e.g. in most probabilistic logics. Here, we present a generic canonical model construction in the semantic framework of coalgebraic modal logic, which pinpoints coherence conditions between syntax and semantics of modal logics that guarantee strong completeness. We apply this method to reconstruct canonical model theorems that are either known or folklore, and moreover instantiate our method to obtain new strong completeness results. In particular, we prove strong completeness of graded modal logic with finite multiplicities, and of the modal logic of exact probabilities.

  15. Strongly Correlated Quantum Walks in Optical Lattices

    OpenAIRE

    Preiss, Philipp M.; Ma, Ruichao; Tai, M. Eric; Lukin, Alexander; Rispoli, Matthew; Zupancic, Philip; Lahini, Yoav; Islam, Rajibul; Greiner, Markus

    2014-01-01

    Full control over the dynamics of interacting, indistinguishable quantum particles is an important prerequisite for the experimental study of strongly correlated quantum matter and the implementation of high-fidelity quantum information processing. Here we demonstrate such control over the quantum walk - the quantum mechanical analogue of the classical random walk - in the strong interaction regime. Using interacting bosonic atoms in an optical lattice, we directly observe fundamental effects...

  16. Model reduction of strong-weak neurons

    OpenAIRE

    Steven James Cox; Bosen eDu; Danny eSorensen

    2014-01-01

    We consider neurons with large dendritic trees that are weakly excitable in the sense that back propagating action potentials are severly attenuated as they travel from the small, strongly excitable, spike initiation zone. In previous work we have shown that the computational size of weakly excitable cell models may be reduced by two or more orders of magnitude, and that the size of strongly excitable models may be reduced by at least one order of magnitude, without sacrificing the spatio–tem...

  17. Evolutionary games on cycles with strong selection

    Science.gov (United States)

    Altrock, P. M.; Traulsen, A.; Nowak, M. A.

    2017-02-01

    Evolutionary games on graphs describe how strategic interactions and population structure determine evolutionary success, quantified by the probability that a single mutant takes over a population. Graph structures, compared to the well-mixed case, can act as amplifiers or suppressors of selection by increasing or decreasing the fixation probability of a beneficial mutant. Properties of the associated mean fixation times can be more intricate, especially when selection is strong. The intuition is that fixation of a beneficial mutant happens fast in a dominance game, that fixation takes very long in a coexistence game, and that strong selection eliminates demographic noise. Here we show that these intuitions can be misleading in structured populations. We analyze mean fixation times on the cycle graph under strong frequency-dependent selection for two different microscopic evolutionary update rules (death-birth and birth-death). We establish exact analytical results for fixation times under strong selection and show that there are coexistence games in which fixation occurs in time polynomial in population size. Depending on the underlying game, we observe inherence of demographic noise even under strong selection if the process is driven by random death before selection for birth of an offspring (death-birth update). In contrast, if selection for an offspring occurs before random removal (birth-death update), then strong selection can remove demographic noise almost entirely.

  18. Earthquake, strong tide and global low temperature

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    "La Madre" is a kind of upper atmospheric air current, and occurs as "warm phase" and "cold phase" in the sky of Pacific Ocean alternately. There exists this phenomenon, called "Oscillation Decade in the Pacific" (ODP), for 20~30years. It is concerned with 60 year cycle of the tides. Lunar oscillations explain an intriguing 60-year cycle in the world's temperature. Strong tides increase the vertical mixing of water in the oceans, drawing cold ocean water from the depths to surface, where it cools the atmosphere above. The first strong seismic episode in China was from 1897 to 1912; the second to the fifth was the in1920-1937, 1946-1957, 1966-1980, 1991-2002, tsrectruely. The alternative boundaries of"La Madre" warm phase and cold phase were in 1890, 1924, 1946 and 2000, which were near the boundaries of four strong earthquakes. It indicated the strong earthquakes closedly related with the substances' motion of atmosphere, hydrosphere and lithosphere, the change of gravity potential, and the exchange of angular momentum. The strong earthquakes in the ocean bottom can bring the cool waters at the deep ocean up to the ocean surface and make the global climate cold. the earthquake, strong tide and global low temperature are close inrelntion for each othen.

  19. Grasping the“lifeline”Firmly, to Provide A Strong Guarantee for the Enterprise Development--Research on How to Deal with Ideological and Political Work of Difficult Enterprise%紧紧把握“生命线”为企业生存和发展提供有力保证--论如何做好困难企业的思想政治工作

    Institute of Scientific and Technical Information of China (English)

    苏如旺

    2013-01-01

    The article expounds difficult enterprises how to give full play to the important role of ideological and political work’s“lifeline”. Enterprise should adhere to the conceptions of people oriented, respecting people and caring about people, should do a good job of leading people, educating people, shaping people, encouraging people and arouse the enthusiasm of cadres and workers, to provide ideological guarantee and spiritual motivation for enterprise going out of the woods.%  文章论述了困难企业如何发挥好思想政治工作的“生命线”作用,坚持以人为本、尊重人、理解人、关心人的理念,做好引导人、教育人、塑造人、激励人的工作,充分调动干部职工的积极性,为企业走出困境提供思想保证和精神动力。

  20. Strong Motion Earthquake Data Values of Digitized Strong-Motion Accelerograms, 1933-1994

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Strong Motion Earthquake Data Values of Digitized Strong-Motion Accelerograms is a database of over 15,000 digitized and processed accelerograph records from...

  1. Spatially: resolved heterogeneous dynamics in a strong colloidal gel

    Science.gov (United States)

    Buzzaccaro, Stefano; Alaimo, Matteo David; Secchi, Eleonora; Piazza, Roberto

    2015-05-01

    We re-examine the classical problem of irreversible colloid aggregation, showing that the application of Digital Fourier Imaging (DFI), a class of optical correlation methods that combine the power of light scattering and imaging, allows one to pick out novel useful evidence concerning the restructuring processes taking place in a strong colloidal gel. In particular, the spatially-resolved displacement fields provided by DFI strongly suggest that the temporally-intermittent local rearrangements taking place in the course of gel ageing are characterized by very long-ranged spatial correlations.

  2. Theory of rf-spectroscopy of strongly interacting fermions.

    Science.gov (United States)

    Punk, M; Zwerger, W

    2007-10-26

    We show that strong pairing correlations in Fermi gases lead to the appearance of a gaplike structure in the rf spectrum, both in the balanced superfluid and in the normal phase above the Clogston-Chandrasekhar limit. The average rf shift of a unitary gas is proportional to the ratio of the Fermi velocity and the scattering length with the final state. In the strongly imbalanced case, the rf spectrum measures the binding energy of a minority atom to the Fermi sea of majority atoms. Our results provide a qualitative understanding of recent experiments by Schunck et al.

  3. Strong gravitational lensing versus dynamic galactic mass

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, Antonio C.C.; Sodre Junior, Laerte [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Astronomia, Geofisica e Ciencias Atmosfericas. Dept. de Astronomia

    2006-07-01

    The mass associated to a galaxy is a fundamental property necessary for its description and for the understating of its structure, formation and evolution. In the cosmological context, the mass and density profile of galaxies and galaxy clusters is relevant for the understanding of dark matter properties and the formation dynamics of structures in the Universe. We find the masses of 15 galaxies from the SLACS Survey through two methods: using the stellar velocity dispersion (dynamic method) and using strong gravitational lensing. We discover a discrepancy between the masses obtained through these two methods and develop several models to explain it. We test the models suggested by calculating {chi}{sup 2} statistics and the Bayesian information criteria. Statistical fluctuation and a constant systematic error are strongly discarded as explanations for the mass discrepancy. Our results show evidence of projection effects on the line of sight that add a contamination mass in the strong lensing galactic mass determination. This effect was already observed in greater detail in weak and strong gravitational lensing measures of cluster of galaxies, but was little explored before in the case of strong lensing by galaxies. (author)

  4. Visible periodicity of strong nucleosome DNA sequences.

    Science.gov (United States)

    Salih, Bilal; Tripathi, Vijay; Trifonov, Edward N

    2015-01-01

    Fifteen years ago, Lowary and Widom assembled nucleosomes on synthetic random sequence DNA molecules, selected the strongest nucleosomes and discovered that the TA dinucleotides in these strong nucleosome sequences often appear at 10-11 bases from one another or at distances which are multiples of this period. We repeated this experiment computationally, on large ensembles of natural genomic sequences, by selecting the strongest nucleosomes--i.e. those with such distances between like-named dinucleotides, multiples of 10.4 bases, the structural and sequence period of nucleosome DNA. The analysis confirmed the periodicity of TA dinucleotides in the strong nucleosomes, and revealed as well other periodic sequence elements, notably classical AA and TT dinucleotides. The matrices of DNA bendability and their simple linear forms--nucleosome positioning motifs--are calculated from the strong nucleosome DNA sequences. The motifs are in full accord with nucleosome positioning sequences derived earlier, thus confirming that the new technique, indeed, detects strong nucleosomes. Species- and isochore-specific variations of the matrices and of the positioning motifs are demonstrated. The strong nucleosome DNA sequences manifest the highest hitherto nucleosome positioning sequence signals, showing the dinucleotide periodicities in directly observable rather than in hidden form.

  5. Approximations for strongly-coupled supersymmetric quantum mechanics

    CERN Document Server

    Kabat, D; Kabat, Daniel; Lifschytz, Gilad

    2000-01-01

    We advocate a set of approximations for studying the finite temperature behavior of strongly-coupled theories in 0+1 dimensions. The approximation consists of expanding about a Gaussian action, with the width of the Gaussian determined by a set of gap equations. The approximation can be applied to supersymmetric systems, provided that the gap equations are formulated in superspace. It can be applied to large-N theories, by keeping just the planar contribution to the gap equations. We analyze several models of scalar supersymmetric quantum mechanics, and show that the Gaussian approximation correctly distinguishes between a moduli space, mass gap, and supersymmetry breaking at strong coupling. Then we apply the approximation to a bosonic large-N gauge theory, and argue that a Gross-Witten transition separates the weak-coupling and strong-coupling regimes. A similar transition should occur in a generic large-N gauge theory, in particular in 0-brane quantum mechanics.

  6. Strongly interacting photons in one-dimensional continuum

    CERN Document Server

    Roy, Dibyendu; Firstenberg, Ofer

    2016-01-01

    The photon-photon scattering in vacuum is extremely weak. However, strong effective interactions between single photons can be realized by employing strong light-matter coupling. These interactions are a fundamental building block for quantum optics, bringing many-body physics to the photonic world and providing important resources for quantum photonic devices and for optical metrology. In this Colloquium, we review the physics of strongly-interacting photons in one-dimensional systems with no optical confinement along the propagation direction. We focus on two recently-demonstrated experimental realizations: (i) superconducting qubits coupled to open transmission lines, and (ii) interacting Rydberg atoms in a cold gas. Advancements in the theoretical understanding of these systems are presented in complementary formalisms and compared to experimental results. The experimental achievements are summarized alongside of a systematic description of the quantum optical effects and quantum devices emerging from the...

  7. AMS-02, Strongly Self-Interacting Dark Matter, and QUD

    CERN Document Server

    White, Alan R

    2014-01-01

    The latest AMS-02 electron/positron precision data add to the spectrum knee as direct cosmic ray evidence for an electroweak scale strong interaction. In addition, there is significant evidence for a strong self-interaction of dark matter. QUD is a unique massless SU(5) field theory with an anomaly-generated bound-state S-Matrix that could be an unconventional origin for the Standard Model. The electroweak scale color sextet quark enhanced QCD interaction is the only new physics. Production of multiple vector bosons, that acquire masses via sextet quark pions, will give the AMS positron and electron cross-sections - related vector boson pair production having been seen at the LHC. Stable sextet quark neutrons (neusons) provide a novel form of very strongly interacting dark matter that has the desired experimental properties. Large rapidity hadronic production of neusons will produce the knee.

  8. Strong interactions in spacelike and timelike domains dispersive approach

    CERN Document Server

    Nesterenko, Alexander V

    2017-01-01

    Strong Interactions in Spacelike and Timelike Domains: Dispersive Approach provides the theoretical basis for the description of the strong interactions in the spacelike and timelike domains. The book primarily focuses on the hadronic vacuum polarization function, R-ratio of electron-positron annihilation into hadrons, and the Adler function, which govern a variety of the strong interaction processes at various energy scales. Specifically, the book presents the essentials of the dispersion relations for these functions, recaps their perturbative calculation, and delineates the dispersively improved perturbation theory. The book also elucidates the peculiarities of the continuation of the spacelike perturbative results into the timelike domain, which is indispensable for the studies of electron-positron annihilation into hadrons and the related processes.

  9. Time varying networks and the weakness of strong ties

    Science.gov (United States)

    Karsai, Márton; Perra, Nicola; Vespignani, Alessandro

    2014-02-01

    In most social and information systems the activity of agents generates rapidly evolving time-varying networks. The temporal variation in networks' connectivity patterns and the ongoing dynamic processes are usually coupled in ways that still challenge our mathematical or computational modelling. Here we analyse a mobile call dataset and find a simple statistical law that characterize the temporal evolution of users' egocentric networks. We encode this observation in a reinforcement process defining a time-varying network model that exhibits the emergence of strong and weak ties. We study the effect of time-varying and heterogeneous interactions on the classic rumour spreading model in both synthetic, and real-world networks. We observe that strong ties severely inhibit information diffusion by confining the spreading process among agents with recurrent communication patterns. This provides the counterintuitive evidence that strong ties may have a negative role in the spreading of information across networks.

  10. Black holes a laboratory for testing strong gravity

    CERN Document Server

    Bambi, Cosimo

    2017-01-01

    This textbook introduces the current astrophysical observations of black holes, and discusses the leading techniques to study the strong gravity region around these objects with electromagnetic radiation. More importantly, it provides the basic tools for writing an astrophysical code and testing the Kerr paradigm. Astrophysical black holes are an ideal laboratory for testing strong gravity. According to general relativity, the spacetime geometry around these objects should be well described by the Kerr solution. The electromagnetic radiation emitted by the gas in the inner part of the accretion disk can probe the metric of the strong gravity region and test the Kerr black hole hypothesis. With exercises and examples in each chapter, as well as calculations and analytical details in the appendix, the book is especially useful to the beginners or graduate students who are familiar with general relativity while they do not have any background in astronomy or astrophysics.

  11. The strong coupling Kondo lattice model as a Fermi gas

    CERN Document Server

    Östlund, S

    2007-01-01

    The strong coupling half-filled Kondo lattice model is an important example of a strongly interacting dense Fermi system for which conventional Fermi gas analysis has thus far failed. We remedy this by deriving an exact transformation that maps the model to a dilute gas of weakly interacting electron and hole quasiparticles that can then be analyzed by conventional dilute Fermi gas methods. The quasiparticle vacuum is a singlet Mott insulator for which the quasiparticle dynamics are simple. Since the transformation is exact, the electron spectral weight sum rules are obeyed exactly. Subtleties in understanding the behavior of electrons in the singlet Mott insulator can be reduced to a fairly complicated but precise relation between quasiparticles and bare electrons. The theory of free quasiparticles can be interpreted as an exactly solvable model for a singlet Mott insulator, providing an exact model in which to explore the strong coupling regime of a singlet Kondo insulator.

  12. Characterisation of Strongly Normalising lambda-mu-Terms

    Directory of Open Access Journals (Sweden)

    Steffen van Bakel

    2013-07-01

    Full Text Available We provide a characterisation of strongly normalising terms of the lambda-mu-calculus by means of a type system that uses intersection and product types. The presence of the latter and a restricted use of the type omega enable us to represent the particular notion of continuation used in the literature for the definition of semantics for the lambda-mu-calculus. This makes it possible to lift the well-known characterisation property for strongly-normalising lambda-terms - that uses intersection types - to the lambda-mu-calculus. From this result an alternative proof of strong normalisation for terms typeable in Parigot's propositional logical system follows, by means of an interpretation of that system into ours.

  13. Electromagnetic Processes in strong Crystalline Fields

    CERN Multimedia

    Uggerhoj, U I; Mikkelsen, F K

    2007-01-01

    We propose a number of new investigations on aspects of radiation from high energy electron and positron beams (10-300 GeV) in single crystals and amorphous targets. The common heading is radiation emission by electrons and positrons in strong electromagnetic fields, but as the setup is quite versatile, other related phenomena in radiation emission can be studied as well. The intent is to clarify the role of a number of important aspects of radiation in strong fields as e.g. observed in crystals. We propose to measure trident 'Klein-like' production in strong crystalline fields, 'crystalline undulator' radiation, 'sandwich' target phenomena, LPM suppression of pair production as well as axial and planar effects in contributions of spin to the radiation.

  14. Nanostructure studies of strongly correlated materials.

    Science.gov (United States)

    Wei, Jiang; Natelson, Douglas

    2011-09-01

    Strongly correlated materials exhibit an amazing variety of phenomena, including metal-insulator transitions, colossal magnetoresistance, and high temperature superconductivity, as strong electron-electron and electron-phonon couplings lead to competing correlated ground states. Recently, researchers have begun to apply nanostructure-based techniques to this class of materials, examining electronic transport properties on previously inaccessible length scales, and applying perturbations to drive systems out of equilibrium. We review progress in this area, particularly emphasizing work in transition metal oxides (Fe(3)O(4), VO(2)), manganites, and high temperature cuprate superconductors. We conclude that such nanostructure-based studies have strong potential to reveal new information about the rich physics at work in these materials.

  15. Electronic Structure of Strongly Correlated Materials

    CERN Document Server

    Anisimov, Vladimir

    2010-01-01

    Electronic structure and physical properties of strongly correlated materials containing elements with partially filled 3d, 4d, 4f and 5f electronic shells is analyzed by Dynamical Mean-Field Theory (DMFT). DMFT is the most universal and effective tool used for the theoretical investigation of electronic states with strong correlation effects. In the present book the basics of the method are given and its application to various material classes is shown. The book is aimed at a broad readership: theoretical physicists and experimentalists studying strongly correlated systems. It also serves as a handbook for students and all those who want to be acquainted with fast developing filed of condensed matter physics.

  16. Modeling and synthesis of strong ground motion

    Indian Academy of Sciences (India)

    S T G Raghu Kanth

    2008-11-01

    Success of earthquake resistant design practices critically depends on how accurately the future ground motion can be determined at a desired site. But very limited recorded data are available about ground motion in India for engineers to rely upon. To identify the needs of engineers, under such circumstances, in estimating ground motion time histories, this article presents a detailed review of literature on modeling and synthesis of strong ground motion data. In particular, modeling of seismic sources and earth medium, analytical and empirical Green’s functions approaches for ground motion simulation, stochastic models for strong motion and ground motion relations are covered. These models can be used to generate realistic near-field and far-field ground motion in regions lacking strong motion data. Numerical examples are shown for illustration by taking Kutch earthquake-2001 as a case study.

  17. Simple supersymmetric strongly coupled preon model

    Science.gov (United States)

    Fajfer, S.; Tadić, D.

    1988-08-01

    This supersymmetric-SU(5) composite model is a natural generalization of the usual strong-coupling models. Preon superfields are in representations 5* and 10. The product representations 5*×10, 5×10, 5×5, and 5*×5 contain only those strongly hypercolor bound states which are needed in the standard electroweak theory. There are no superfluous quarklike states. The neutrino is massless. Only one strongly hypercolor bound singlet (10×10*) can exist as a free particle. At higher energies one should expect to see a plethora of new particles. Grand unification happens at the scale M~1014 GeV. Cabibbo mixing can be incorporated by using a transposed Kobayashi-Maskawa mixing matrix.

  18. Generalized Strong Curvature Singularities and Cosmic Censorship

    CERN Document Server

    Rudnicki, W; Kondracki, W

    2002-01-01

    A new definition of a strong curvature singularity is proposed. This definition is motivated by the definitions given by Tipler and Krolak, but is significantly different and more general. All causal geodesics terminating at these new singularities, which we call generalized strong curvature singularities, are classified into three possible types; the classification is based on certain relations between the curvature strength of the singularities and the causal structure in their neighborhood. A cosmic censorship theorem is formulated and proved which shows that only one class of generalized strong curvature singularities, corresponding to a single type of geodesics according to our classification, can be naked. Implications of this result for the cosmic censorship hypothesis are indicated.

  19. Effective action for strongly correlated electron systems

    Energy Technology Data Exchange (ETDEWEB)

    Ferraz, A., E-mail: aferraz.iccmp@gmail.com [International Institute of Physics - UFRN, Department of Experimental and Theoretical Physics - UFRN, Natal (Brazil); Kochetov, E.A. [International Institute of Physics - UFRN, Natal (Brazil); Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)

    2011-12-21

    The su(2|1) coherent-state path-integral representation of the partition function of the t-J model of strongly correlated electrons is derived at finite doping. The emergent effective action is compared to the one proposed earlier on phenomenological grounds by Shankar to describe holes in an antiferromagnet [R. Shankar, Nucl. Phys. B 330 (1990) 433]. The t-J model effective action is found to have an important 'extra' factor with no analogue in Shankar's action. It represents the local constraint of no double electron occupancy and reflects the rearrangement of the underlying phase-space manifold due to the presence of strong electron correlation. This important ingredient is shown to be essential to describe the physics of strongly correlated electron systems.

  20. Strong Coupling between Plasmons and Organic Semiconductors

    Directory of Open Access Journals (Sweden)

    Joel Bellessa

    2014-05-01

    Full Text Available In this paper we describe the properties of organic material in strong coupling with plasmon, mainly based on our work in this field of research. The strong coupling modifies the optical transitions of the structure, and occurs when the interaction between molecules and plasmon prevails on the damping of the system. We describe the dispersion relation of different plasmonic systems, delocalized and localized plasmon, coupled to aggregated dyes and the typical properties of these systems in strong coupling. The modification of the dye emission is also studied. In the second part, the effect of the microscopic structure of the organics, which can be seen as a disordered film, is described. As the different molecules couple to the same plasmon mode, an extended coherent state on several microns is observed.

  1. Strong diquark correlations inside the proton

    Directory of Open Access Journals (Sweden)

    Segovia Jorge

    2016-01-01

    Full Text Available Quantum Chromodynamics is thought to be the relativistic quantum field theory that describes the strong interaction of the Standard Model. This interaction produces mesons but it is also able to generate quark-quark (diquark correlations inside baryons. In this work, we employ a continuum approach to QCD based on Dyson-Schwinger equations to calculate the electromagnetic form factors of the proton and analyze in a deeper way the consequences of having strong diquark correlations. Comparison with the experimental data reveals that the presence of strong diquark correlations within the proton is sufficient to understand empirical extractions of the flavour-separated form factors. The explained reduction of the ratios F1d/F1u and F2d/F2u at high Q2 in the quark-diquark picture are responsible of the precocious scaling of the F2p/F1p observed experimentally.

  2. Combinatorics of Lattice QCD at Strong Coupling

    CERN Document Server

    Unger, Wolfgang

    2014-01-01

    Thermodynamics in the strong coupling limit of lattice QCD has features which may be similar to those of continuum QCD, such as a chiral critical end point and a nuclear liquid gas transition. Here I compare the combinatorics of staggered and Wilson fermions in the strong coupling limit for arbitrary number of colors and flavors. The partition functions can be considered as an expansions in hadronic spatial hoppings from the static limit, where both discretizations can be expressed via formulae with coefficients of distinct combinatorial interpretation. The corresponding multiplicites of hadronic states are evaluated using generalizations of Catalan numbers and Lucas polynomials. I outline how quantum Monte Carlo simulations can be carried out in general, and summarize recent results on the gauge corrections to the strong coupling limit.

  3. Global gyrokinetic simulations with strong flows

    Science.gov (United States)

    Collier, J. D.; McMillan, B. F.; Robinson, J. R.

    2016-11-01

    We report on the investigation of strong toroidal rotation effects in a global tokamak code, ORB5. This includes the implementation of a strong flow gyrokinetic Lagrangian, allowing a complete treatment of centrifugal and Coriolis effects in the laboratory frame. In order to consistently perform the linear analysis in this system, an axisymmetric gyrokinetic equilibrium distribution function is defined using the constants of motion: we show it corresponds to the standard choice in the local limit and is close to the neoclassical solution in the banana regime. The energy and momentum transport equations are presented in an analogous form to those for the weak flow system. Linear studies of Ion Temperature Gradient (ITG) modes in rotating plasmas are performed to determine how the global effects interact with the effects of strong rotation. We also determine the geodesic acoustic mode dispersion with respect to plasma rotation rate in this gyrokinetic model and compare it to MHD theory.

  4. The strong side of weak topological insulators

    Science.gov (United States)

    Kraus, Yaacov; Ringel, Zohar; Stern, Ady

    2012-02-01

    Three-dimensional topological insulators are classified into ``strong'' (STI) and ``weak'' (WTI) according to the nature of their surface states. While the surface states of the STI are topologically protected, in the WTI they are believed to be very fragile to disorder. In this work we show that the WTI surface states are actually protected from any random perturbation which does not break time-reversal symmetry, and does not close the bulk energy gap. Consequently, the conductivity of metallic surfaces in the clean system will remain finite even in the presence of strong disorder of this type. In the weak disorder limit the surfaces are perfect metals, and strong surface disorder only acts to push them inwards. We find that WTI's differ from STI's primarily in their anisotropy, and that the anisotropy is not a sign of their weakness but rather of their richness.

  5. Inflationary Magnetogenesis without the Strong Coupling Problem

    CERN Document Server

    Ferreira, Ricardo J Z; Sloth, Martin S

    2013-01-01

    The simplest gauge invariant models of inflationary magnetogenesis are known to suffer from the problems of either large back reaction or strong coupling, which make it difficult to self-consistently achieve cosmic magnetic fields from inflation with a field strength larger than $10^{-32}$ Gauss today on the $\\Mpc$ scale. Such a strength is insufficient to act as seeds for the galactic dynamo effect, which requires a magnetic field larger than $10^{-20}$ Gauss. In this paper we propose a new simple model, which avoids both the strong coupling and the back reaction problems, and can lead to cosmic magnetic fields from inflation as large as about $10^{-16}$ Gauss today on the $\\Mpc$ scale, thus improving the previous result by 16 orders of magnitude. In the scenario presented here, the coupling function which breaks the conformal invariance of electromagnetism is non-monotonic with sharp features avoiding previous back reaction and strong coupling constraints.

  6. Strongly Coupled Graphene on the Lattice

    CERN Document Server

    Lähde, Timo A

    2011-01-01

    The two-dimensional carbon allotrope graphene has recently attracted a lot of attention from researchers in the disciplines of Lattice Field Theory, Lattice QCD and Monte Carlo calculations. This interest has been prompted by several remarkable properties of the conduction electrons in graphene. For instance, the conical band structure of graphene at low energies is strongly reminiscent of relativistic Dirac fermions. Also, due the low Fermi velocity of v_F = c/300, where c is the speed of light in vacuum, the physics of the conduction electrons in graphene is qualitatively similar to Quantum Electrodynamics in a strongly coupled regime. In turn, this opens up the prospect of the experimental realization of gapped, strongly correlated states in the electronic phase diagram of graphene. Here, we review the experimental and theoretical motivations for Lattice Field Theory studies of graphene, and describe the directions that such research is likely to progress in during the next few years. We also give a brief ...

  7. Cosmological Particle Production at Strong Coupling

    CERN Document Server

    Rangamani, Mukund; Van Raamsdonk, Mark

    2015-01-01

    We study the dynamics of a strongly-coupled quantum field theory in a cosmological spacetime using the holographic AdS/CFT correspondence. Specifically we consider a confining gauge theory in an expanding FRW universe and track the evolution of the stress-energy tensor during a period of expansion, varying the initial temperature as well as the rate and amplitude of the expansion. At strong coupling, particle production is inseparable from entropy production. As a result, we find significant qualitative differences from the weak coupling results: at strong coupling the system rapidly loses memory of its initial state as the amplitude is increased. Furthermore, in the regime where the Hubble parameter is parametrically smaller than the initial temperature, the dynamics is well modelled as a plasma evolving hydrodynamically towards equilibrium.

  8. Quantum Transport in Strongly Correlated Systems

    DEFF Research Database (Denmark)

    Bohr, Dan

    2007-01-01

    the density matrix renormalization group (DMRG) method. We present two DMRG setups for calculating the linear conductance of strongly correlated nanostructures in the infinitesimal source-drain voltage regime. The first setup describes the leads by modified real-space tight-binding chains, whereas the second...... describes the leads in momentum-space. We benchmark each of these schemes against exact Greens function results for the conductance in the non-interacting limit, thus demonstrating the accuracy of the lead descriptions. We first use the DMRG implementations to calculate the conductance of an interacting...... spinless resonant 7 site chain, studying the effect of repulsive interaction inside the chain. We demonstrate that both weak and strong interactions inside the chain lead to Coulomb blockade renormalization of the resonances in the conductance spectrum. Additionally the strongly interacting case sharpens...

  9. Strong coupling, discrete symmetry and flavour

    CERN Document Server

    Abel, Steven

    2010-01-01

    We show how two principles - strong coupling and discrete symmetry - can work together to generate the flavour structure of the Standard Model. We propose that in the UV the full theory has a discrete flavour symmetry, typically only associated with tribimaximal mixing in the neutrino sector. Hierarchies in the particle masses and mixing matrices then emerge from multiple strongly coupled sectors that break this symmetry. This allows for a realistic flavour structure, even in models built around an underlying grand unified theory. We use two different techniques to understand the strongly coupled physics: confinement in N=1 supersymmetry and the AdS/CFT correspondence. Both approaches yield equivalent results and can be represented in a clear, graphical way where the flavour symmetry is realised geometrically.

  10. Research on strong earthquake type division and forecast method for subsequent strong earthquakes

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The relationships between energy, amplitude and frequency of earthquake are correlative with the property of the seismic source. And the grade of the correlativity can be used as an index to distinguish the types of strong earthquakes. Primarily the strong earthquake can be divided into three types of main-after earthquakes, double-main earthquakes and swarm of strong earthquake. There are similarity and a certain repeatability at the quantificational indexes of hypocenter property between the same type of strong earthquakes, which supply basis for the forecast of subsequent strong shocks. The reference indexes of after strong shock forecast which are valuable for the applications of the method of type-divided forecast come from the analysis about more than fifty strong shock wide-band (BPZ wave) recording data of CDSN from 1988 to 1997.

  11. Gluon scattering amplitudes at strong coupling

    Energy Technology Data Exchange (ETDEWEB)

    Alday, Luis F. [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, 3508 TD Utrecht (Netherlands); Maldacena, Juan [School of Natural Sciences, Institute for Advanced Study, Princeton, NJ 08540 (United States)

    2007-06-15

    We describe how to compute planar gluon scattering amplitudes at strong coupling in N = 4 super Yang Mills by using the gauge/string duality. The computation boils down to finding a certain classical string configuration whose boundary conditions are determined by the gluon momenta. The results are infrared divergent. We introduce the gravity version of dimensional regularization to define finite quantities. The leading and subleading IR divergencies are characterized by two functions of the coupling that we compute at strong coupling. We compute also the full finite form for the four point amplitude and we find agreement with a recent ansatz by Bern, Dixon and Smirnov.

  12. Hyperon Stars in Strong Magnetic Fields

    CERN Document Server

    Gomes, R O; Vasconcellos, C A Z

    2013-01-01

    We investigate the effects of strong magnetic fields on the properties of hyperon stars. The matter is described by a hadronic model with parametric coupling. The matter is considered to be at zero temperature, charge neutral, beta-equilibrated, containing the baryonic octet, electrons and muons. The charged particles have their orbital motions Landau-quantized in the presence of strong magnetic fields (SMF). Two parametrisations of a chemical potential dependent static magnetic field are considered, reaching $1-2 \\times 10^{18}\\,G$ in the center of the star. Finally, the Tolman-Oppenheimer-Volkov (TOV) equations are solved to obtain the mass-radius relation and population of the stars.

  13. Strong-coupling diffusion in relativistic systems

    Indian Academy of Sciences (India)

    Georg Wolschin

    2003-05-01

    Different from the early universe, heavy-ion collisions at very high energies do not reach statistical equilibrium, although thermal models explain many of their features. To account for nonequilibrium strong-coupling effects, a Fokker–Planck equation with time-dependent diffusion coefficient is proposed. A schematic model for rapidity distributions of participant baryons is set up and solved analytically. The evolution from SIS via AGS and SPS to RHIC energies is discussed. Strong-coupling diffusion produces double-peaked spectra in central collisions at the higher SPS momentum of 158 A$\\cdot$GeV/c and beyond.

  14. Stability of Strongly Gauduchon Manifolds under Modifications

    CERN Document Server

    Popovici, Dan

    2010-01-01

    In our previous works on deformation limits of projective and Moishezon manifolds, we introduced and made crucial use of the notion of strongly Gauduchon metrics as a reinforcement of the earlier notion of Gauduchon metrics. Using direct and inverse images of closed positive currents of type $(1, \\, 1)$ and regularisation, we now show that compact complex manifolds carrying strongly Gauduchon metrics are stable under modifications. This stability property, known to fail for compact K\\"ahler manifolds, mirrors the modification stability of balanced manifolds proved by Alessandrini and Bassanelli.

  15. Strong Dynamics and Inflation: a review

    CERN Document Server

    Channuie, Phongpichit

    2014-01-01

    In this article, we review how strong dynamics can be efficiently employed as a viable alternative to study the mechanism of cosmic inflation. We examine single-field inflation in which the inflaton emerges as a bound state stemming from various strongly interacting field theories. We constrain the number of e-foldings for composite models of inflation in order to obtain a successful inflation. We study a set of cosmological parameters, e.g., the primordial spectral index $n_{s}$ and tensor-to-scalar ratio $r$, and confront the predicted results with the joint Planck data, and with the recent BICEP2 data.

  16. Strong-Field Resonant Dynamics in Semiconductors.

    Science.gov (United States)

    Wismer, Michael S; Kruchinin, Stanislav Yu; Ciappina, Marcelo; Stockman, Mark I; Yakovlev, Vladislav S

    2016-05-13

    We predict that a direct band gap semiconductor (GaAs) resonantly excited by a strong ultrashort laser pulse exhibits a novel regime: kicked anharmonic Rabi oscillations. In this regime, Rabi oscillations are strongly coupled to intraband motion, and interband transitions mainly take place when electrons pass near the Brillouin zone center where electron populations undergo very rapid changes. The asymmetry of the residual population distribution induces an electric current controlled by the carrier-envelope phase of the driving pulse. The predicted effects are experimentally observable using photoemission and terahertz spectroscopies.

  17. Strong Antigravity. Life in the Shock Wave

    CERN Document Server

    Fabbrichesi, Marco E

    1992-01-01

    Strong anti-gravity is the vanishing to all orders in Newton's constant of the net force between two massive particles at rest. We study this phenomenon and show that it occurs in any effective theory of gravity which is obtained from a higher-dimensional model by compactification on a manifold with flat directions. We find the exact solution of the Einstein equations in the presence of a point-like source of strong anti-gravity by dimensional reduction of what is a shock-wave solution in the higher-dimensional model. (Latex file, no macros, figures not included)

  18. Thermodynamics of strongly disordered spin ladders

    OpenAIRE

    Yusuf, Eddy; Yang, Kun

    2002-01-01

    We study antiferromagnetic two-leg spin-1/2 ladders with strong bond randomness, using the real space renormalization group method. We find the low-temperature spin susceptibility of the system follows non-universal power laws, and the ground state spin-spin correlation is short-ranged. Our results suggest that there is no phase transition when the bond randomness increases from zero; for strong enough randomness the system is in a Griffith region with divergent spin susceptibility and short-...

  19. Experimental investigation of strong field trident production

    CERN Document Server

    Esberg, J; Knudsen, H; Thomsen, H D; Uggerhøj, E; Uggerhøj1, U I; Sona, P; Mangiarotti, A; Ketel, T J; Dizdar, A; Dalton, M M; Ballestrero, S; Connell, S H

    2010-01-01

    We show by experiment that an electron impinging on an electric field that is of critical magnitude in its rest frame, may produce an electron-positron pair. Our measurements address higher-order QED, using the strong electric fields obtainable along particular crystallographic directions in single crystals. For the amorphous material our data are in good agreement with theory, whereas a discrepancy with theory on the magnitude of the trident enhancement is found in the precisely aligned case where the strong electric field acts.

  20. Strong Langmuir turbulence in Kappa distributed plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Liu Sanqiu [Department of Physics and School of Materials Science and Engineering, Nanchang University, Nanchang, 330047 (China); Chen Hui [School of Materials Science and Engineering, Nanchang University, Nanchang 330047 (China)

    2012-01-15

    Superthermal electrons are often observed in space and astrophysics and can be appropriate modeled by the family of Kappa distribution functions. Taking the nonlinear wave-wave, wave-particle interactions and the effect of superthermal electrons into account, the strong Langmuir turbulence is investigated in kinetic regime. The modified Zakharov equations are obtained for the case of no damping or driving terms. On the basis of these equations, dynamics of collapse have been studied by the means of the general virial theorem, and the collapse thresholds which are strong modified by superthermal index {kappa}{sub e} are given.

  1. Strong dynamics and inflation: A review

    Directory of Open Access Journals (Sweden)

    Phongpichit Channuie

    2015-03-01

    Full Text Available In this article, we review how strong dynamics can be efficiently employed as a viable alternative to study the mechanism of cosmic inflation. We examine single-field inflation in which the inflaton emerges as a bound state stemming from various strongly interacting field theories. We constrain the number of e-foldings for composite models of inflation in order to obtain a successful inflation. We study a set of cosmological parameters, e.g., the primordial spectral index ns and tensor-to-scalar ratio r, and confront the predicted results with the joint Planck data, and with the recent BICEP2 data.

  2. Strong boundedness of analytic functions in tubes

    Directory of Open Access Journals (Sweden)

    Richard D. Carmichael

    1979-01-01

    Full Text Available Certain classes of analytic functions in tube domains TC=ℝn+iC in n-dimensional complex space, where C is an open connected cone in ℝn, are studied. We show that the functions have a boundedness property in the strong topology of the space of tempered distributions g′. We further give a direct proof that each analytic function attains the Fourier transform of its spectral function as distributional boundary value in the strong (and weak topology of g′.

  3. The Determination of the Strong Coupling Constant

    Science.gov (United States)

    Dissertori, Günther

    2016-10-01

    The strong coupling constant is one of the fundamental parameters of the Standard Theory of particle physics. In this review I will briefly summarise the theoretical framework, within which the strong coupling constant is defined and how it is connected to measurable observables. Then I will give an historical overview of its experimental determinations and discuss the current status and world average value. Among the many different techniques used to determine this coupling constant in the context of quantum chromodynamics, I will focus in particular on a number of measurements carried out at the Large Electron-Positron Collider (LEP) and the Large Hadron Collider (LHC) at CERN.

  4. Nonlinear Electron Waves in Strongly Magnetized Plasmas

    DEFF Research Database (Denmark)

    Pécseli, Hans; Juul Rasmussen, Jens

    1980-01-01

    dynamics in the analysis is also demonstrated. As a particular case the authors investigate nonlinear waves in a strongly magnetized plasma filled wave-guide, where the effects of finite geometry are important. The relevance of this problem to laboratory experiments is discussed.......Weakly nonlinear dispersive electron waves in strongly magnetized plasma are considered. A modified nonlinear Schrodinger equation is derived taking into account the effect of particles resonating with the group velocity of the waves (nonlinear Landau damping). The possibility of including the ion...

  5. Strong converse theorems using Rényi entropies

    Science.gov (United States)

    Leditzky, Felix; Wilde, Mark M.; Datta, Nilanjana

    2016-08-01

    We use a Rényi entropy method to prove strong converse theorems for certain information-theoretic tasks which involve local operations and quantum (or classical) communication between two parties. These include state redistribution, coherent state merging, quantum state splitting, measurement compression with quantum side information, randomness extraction against quantum side information, and data compression with quantum side information. The method we employ in proving these results extends ideas developed by Sharma [preprint arXiv:1404.5940 [quant-ph] (2014)], which he used to give a new proof of the strong converse theorem for state merging. For state redistribution, we prove the strong converse property for the boundary of the entire achievable rate region in the (e, q)-plane, where e and q denote the entanglement cost and quantum communication cost, respectively. In the case of measurement compression with quantum side information, we prove a strong converse theorem for the classical communication cost, which is a new result extending the previously known weak converse. For the remaining tasks, we provide new proofs for strong converse theorems previously established using smooth entropies. For each task, we obtain the strong converse theorem from explicit bounds on the figure of merit of the task in terms of a Rényi generalization of the optimal rate. Hence, we identify candidates for the strong converse exponents for each task discussed in this paper. To prove our results, we establish various new entropic inequalities, which might be of independent interest. These involve conditional entropies and mutual information derived from the sandwiched Rényi divergence. In particular, we obtain novel bounds relating these quantities, as well as the Rényi conditional mutual information, to the fidelity of two quantum states.

  6. Strong reciprocity, human cooperation, and the enforcement of social norms.

    Science.gov (United States)

    Fehr, Ernst; Fischbacher, Urs; Gächter, Simon

    2002-03-01

    This paper provides strong evidence challenging the self-interest assumption that dominates the behavioral sciences and much evolutionary thinking. The evidence indicates that many people have a tendency to voluntarily cooperate, if treated fairly, and to punish noncooperators. We call this behavioral propensity "strong reciprocity" and show empirically that it can lead to almost universal cooperation in circumstances in which purely self-interested behavior would cause a complete breakdown of cooperation. In addition, we show that people are willing to punish those who behaved unfairly towards a third person or who defected in a Prisoner's Dilemma game with a third person. This suggests that strong reciprocity is a powerful device for the enforcement of social norms involving, for example, food sharing or collective action. Strong reciprocity cannot be rationalized as an adaptive trait by the leading evolutionary theories of human cooperation (in other words, kin selection, reciprocal altruism, indirect reciprocity, and costly signaling theory). However, multilevel selection theories of cultural evolution are consistent with strong reciprocity.

  7. Strongly Scale-dependent Non-Gaussianity

    DEFF Research Database (Denmark)

    Riotto, Antonio; Sloth, Martin Snoager

    2010-01-01

    We discuss models of primordial density perturbations where the non-Gaussianity is strongly scale-dependent. In particular, the non-Gaussianity may have a sharp cut-off and be very suppressed on large cosmological scales, but sizeable on small scales. This may have an impact on probes of non...

  8. The Shape of Strongly Disturbed Dayside Magnetopause

    Directory of Open Access Journals (Sweden)

    Alexei V. Dmitriev Alla V. Suvorova

    2013-01-01

    Full Text Available During strong geomagnetic disturbances, the Earth¡¦s magnetosphere exhibits unusual and nonlinear interaction with the incident flow of magnetized solar wind plasma. Global Magneto-hydro-dynamic (MHD modeling of the magnetosphere predicts that the storm-time effects at the magnetopause result from the abnormal plasma transport and/or extremely strong field aligned currents. In-situ observations of the magnetospheric boundary, magnetopause, by Geosynchronous Operational Environmental Satellite (GOES allowed us to find experimentally such effects as a saturation of the dayside reconnection, unusual bluntness and prominent duskward skewing of the nose magnetopause. The saturation and duskward skewing were attributed to the storm-time magnetopause formation under strong southward interplanetary magnetic field (IMF. The unusual bluntness was observed during both high solar wind pressure and strong southward IMF. We suggest that these phenomena are caused by a substantial contribution of the cross-tail current magnetic field and the hot magnetospheric plasma from the asymmetrical ring current into the pressure balance at the dayside magnetopause.

  9. Cosmological applications of strong gravitational lensing

    DEFF Research Database (Denmark)

    Paraficz, Danuta

    value of the energy density of the two above components, together with measuring the Hubble constant that determines the age of the Universe, is a major goal of modern astrophysics. An interesting method for estimating these parameters is strong gravitational lensing of quasars (QSOs). As shown...

  10. Bottomonia: open bottom strong decays and spectrum

    Directory of Open Access Journals (Sweden)

    Santopinto E.

    2014-05-01

    Full Text Available We present our results for the bottomonium spectrum with self energy corrections. The bare masses used in the calculation are computed within Godfrey and Isgur’s relativized quark model. We also discuss our results for the open bottom strong decay widths of higher bottomonia in the 3P0 pair-creation model.

  11. Strong wind climatic zones in South Africa

    CSIR Research Space (South Africa)

    Kruger, AC

    2010-01-01

    Full Text Available In this paper South Africa is divided into strong wind climate zones, which indicate the main sources of annual maximum wind gusts. By the analysis of wind gust data of 94 weather stations, which had continuous climate time series of 10 years...

  12. Strongly 2-connected orientations of graphs

    DEFF Research Database (Denmark)

    Thomassen, Carsten

    2014-01-01

    We prove that a graph admits a strongly 2-connected orientation if and only if it is 4-edge-connected, and every vertex-deleted subgraph is 2-edge-connected. In particular, every 4-connected graph has such an orientation while no cubic 3-connected graph has such an orientation....

  13. Strong motion duration and earthquake magnitude relationships

    Energy Technology Data Exchange (ETDEWEB)

    Salmon, M.W.; Short, S.A. [EQE International, Inc., San Francisco, CA (United States); Kennedy, R.P. [RPK Structural Mechanics Consulting, Yorba Linda, CA (United States)

    1992-06-01

    Earthquake duration is the total time of ground shaking from the arrival of seismic waves until the return to ambient conditions. Much of this time is at relatively low shaking levels which have little effect on seismic structural response and on earthquake damage potential. As a result, a parameter termed ``strong motion duration`` has been defined by a number of investigators to be used for the purpose of evaluating seismic response and assessing the potential for structural damage due to earthquakes. This report presents methods for determining strong motion duration and a time history envelope function appropriate for various evaluation purposes, for earthquake magnitude and distance, and for site soil properties. There are numerous definitions of strong motion duration. For most of these definitions, empirical studies have been completed which relate duration to earthquake magnitude and distance and to site soil properties. Each of these definitions recognizes that only the portion of an earthquake record which has sufficiently high acceleration amplitude, energy content, or some other parameters significantly affects seismic response. Studies have been performed which indicate that the portion of an earthquake record in which the power (average rate of energy input) is maximum correlates most closely with potential damage to stiff nuclear power plant structures. Hence, this report will concentrate on energy based strong motion duration definitions.

  14. Strongly interacting two-dimensional Dirac fermions

    NARCIS (Netherlands)

    Lim, L.K.; Lazarides, A.; Hemmerich, Andreas; de Morais Smith, C.

    2009-01-01

    We show how strongly interacting two-dimensional Dirac fermions can be realized with ultracold atoms in a two-dimensional optical square lattice with an experimentally realistic, inherent gauge field, which breaks time reversal and inversion symmetries. We find remarkable phenomena in a temperature

  15. Strong industrial base vital for economic revival

    CERN Multimedia

    2001-01-01

    At the inauguration of a 2-day conference on nuclear technology in Islamabad, the chairman of PAEC said that Pakistan needs to develop a strong industrial base and capability to export equipment to improve the economic condition of the country. He descibed how Pakistan has already had a breakthrough with the export of equipment to CERN, Geneva (1 page).

  16. Spin Wave Theory of Strongly Anisotropic Magnets

    DEFF Research Database (Denmark)

    Lindgård, Per-Anker

    1977-01-01

    A strong anisotropy gives rise to a non-spherical precession of the spins with different amplitudes in the x and y directions. The highly anharmonic exchange interaction thereby becomes effectively anisotropic. The possibility of detecting a genuine two-ion anisotropy is discussed, and comments a...

  17. A strong start, a promising future

    Institute of Scientific and Technical Information of China (English)

    Zihe Rao

    2011-01-01

    @@ Protein & Cell has made a very strong start in its first full year of publication, covering 12 monthly issues with a consistently high standard of content and production. Thanks to the contributors, editors, editorial board, editodal staff and publishers, both the scientific quality and the production quality of the journal have been outstanding.

  18. Three Strands Form Strong School Leadership

    Science.gov (United States)

    Saphier, Jon; King, Matt; D'Auria, John

    2006-01-01

    In this article, the authors illustrate the three fundamental elements of school leadership: academic focus, shared beliefs and values, and productive professional relationships. These three elements purportedly produce strong organizational cultures, more teaching expertise, and better student achievement and more thoughtful and caring citizens.…

  19. Strong lensing interferometry for compact binaries

    NARCIS (Netherlands)

    Pen, U.L.; Yang, I.S.

    2015-01-01

    We propose a possibility to improve the current precision measurements on compact binaries. When the orbital axis is almost perpendicular to our line of sight, a pulsar behind its companion can form two strong lensing images. These images cannot be resolved, but we can use multiwavelength interferom

  20. Strong convergence results for hemivariational inequalities

    Institute of Scientific and Technical Information of China (English)

    LIU Zhenhai; ZOU Jiezhong

    2006-01-01

    The purpose of this paper is to study a regularization method of solutions of ill-posed problems involving hemivariational inequalities in Banach spaces. Under the assumption that the hemivariational inequality is solvable, a strongly convergent approximation procedure is designed by means of the so-called Browder-Tikhonov regularization method. Our results generalize and extend the previously known theorems.

  1. Riesz basis for strongly continuous groups

    NARCIS (Netherlands)

    Zwart, Hans

    2010-01-01

    Given a Hilbert space and the generator of a strongly continuous group on this Hilbert space. If the eigenvalues of the generator have a uniform gap, and if the span of the corresponding eigenvectors is dense, then these eigenvectors form a Riesz basis (or unconditional basis) of the Hilbert space.

  2. Quantum transport velocity in strongly scattering media

    NARCIS (Netherlands)

    Malfliet, R

    1998-01-01

    Based on the Kadanoff-Baym equations of quantum transport: theory, an approach is proposed which goes beyond the usual quasiparticle approximation. It allows one to deduct the correct transport velocity for propagation in strongly scattering media, a quantity of great importance for localization phe

  3. Strong suppression of weak localization in graphene

    NARCIS (Netherlands)

    Morozov, S.V.; Novoselov, K.S.; Katsnelson, M.I.; Schedin, F.; Ponomarenko, L.A.; Jiang, D.; Geim, A.K.

    2006-01-01

    Low-field magnetoresistance is ubiquitous in low-dimensional metallic systems with high resistivity and well understood as arising due to quantum interference on self-intersecting diffusive trajectories. We have found that in graphene this weak-localization magnetoresistance is strongly suppressed a

  4. Ken Wilson: Solving the Strong Interactions

    CERN Document Server

    Peskin, Michael E

    2014-01-01

    Ken Wilson's ideas on the renormalization group were shaped by his attempts to build a theory of the strong interactions based on the concepts of quantum field theory. I describe the development of his ideas by reviewing four of Wilson's most important papers. [contribution to the Journal of Statistical Physics Special Issue in Memory of K. G. Wilson

  5. WEAKLY ALGEBRAIC REFLEXIVITY AND STRONGLY ALGEBRAIC REFLEXIVITY

    Institute of Scientific and Technical Information of China (English)

    TaoChangli; LuShijie; ChenPeixin

    2002-01-01

    Algebraic reflexivity introduced by Hadwin is related to linear interpolation. In this paper, the concepts of weakly algebraic reflexivity and strongly algebraic reflexivity which are also related to linear interpolation are introduced. Some properties of them are obtained and some relations between them revealed.

  6. On Strong Memes in Brand Names

    Institute of Scientific and Technical Information of China (English)

    王琳

    2014-01-01

    Based on the memetics and through a large number of examples, this paper expounds several effective methods to cre-ate strong brand name memes. It’s hoped that this paper will offer brand name designers some useful advice on how to create suc-cessful brand name memes.

  7. Strong Ties in a Small World

    NARCIS (Netherlands)

    M.J. van der Leij (Marco); S. Goyal (Sanjeev)

    2006-01-01

    textabstractIn this paper we test the celebrated `Strength of weak ties' theory of Granovetter (1973). We test two hypotheses on the network structure in a data set of collaborating economists. While we find support for the hypothesis of transitivity of strong ties, we reject the hypothesis that wea

  8. Diphoton resonance from a new strong force

    Science.gov (United States)

    Georgi, Howard; Nakai, Yuichiro

    2016-10-01

    We explore a "partial unification" model that a new strong gauge group is combined with the ordinary color and hypercharge gauge groups. The VEV responsible for the combination is of the order of the S U (2 )×U (1 ) breaking scale, but the coupling of the new physics to standard model particles is suppressed by the strong interaction of the new gauge group. This simple extension of the standard model has a rich phenomenology, including composite particles of the new confining gauge interaction, a coloron and a Z' which are rather weakly coupled to standard model particles, and massive vector bosons charged under both the ordinary color and hypercharge gauge groups and the new strong gauge group. The new scalar glueball could be produced by gluon fusion and decay into two photons, both through loops of the new massive vector bosons. The simplest version of the model has some issues: the massive vector bosons are stable and the coloron and the Z' are strongly constrained by search data. An extension of the model to include additional fermions with the new gauge coupling, though not as simple and elegant, can address both issues and more. It allows the massive vector boson to decay into a colorless, neutral state that could be a candidate of the dark matter. And the coloron and Z' can decay dominantly into the new fermions, completely changing the search bounds. If the massive vector bosons are still long lived, they could form new bound states, "vector bosoniums" with additional interesting phenomenology. The model is an explicit example of how new physics at small scales could be hidden by strong interactions.

  9. Super-strong magneto-rheological fluids

    Science.gov (United States)

    Tao, R.

    2001-03-01

    A typical MR fluid is a suspension of magnetic particles of micrometer size in a liquid. Upon application of a strong magnetic field, the fluid turns into a solid. This process is reversible and the response time is of milliseconds. MR fluids presently have a yield shear stress around 80 kPa, which is adequate for applications in shock absorbers and vibration dampers, but is inadequate for automobile clutch etc. Efforts in searching for new materials in the past decades came with limited results. Thus we have developed a new approach to change the microstructure of MR fluids and make them super-strong. It is well known that under a strong magnetic field, the ideal structure of MR fluids is a body-centered tetragonal (bct) lattice. The mechanical strength of MR fluids strongly depends on the microstructure. A bct-lattice based thick column has a much higher yield stress than a single-chain structure. When a magnetic field is applied to a MR fluid, the particles first form chains. With time, the chains may aggregate into columns. However, the unassisted aggregation is not very useful, as it is slow and produces columns with a limited thickness. Our method is based on assisted aggregations. Immediately after a magnetic field is applied, we compress the MR fluid in the field direction before a shear force is applied. The compression pushes the induced chains together to form thick columns. This microstructure change greatly enhances the yield stress. The experiment on an iron-based MR fluid finds 800 kPa for the yield stress, ten times stronger than that without the compression. When the magnetic field is removed, the MR fluid still returns to the liquid state quickly. The upper limit of this structure-enhanced yield stress seems well above 800 kPa. The super-strong MR fluids are suitable for many industrial applications. *Supported by NSF Grant 0196022

  10. Dynamic Stark effect in strongly coupled microcavity exciton polaritons.

    Science.gov (United States)

    Hayat, Alex; Lange, Christoph; Rozema, Lee A; Darabi, Ardavan; van Driel, Henry M; Steinberg, Aephraim M; Nelsen, Bryan; Snoke, David W; Pfeiffer, Loren N; West, Kenneth W

    2012-07-20

    We present experimental observations of a nonresonant dynamic Stark shift in strongly coupled microcavity quantum well exciton polaritons--a system which provides a rich variety of solid-state collective phenomena. The Stark effect is demonstrated in a GaAs/AlGaAs system at 10 K by femtosecond pump-probe measurements, with the blueshift approaching the meV scale for a pump fluence of 2  mJ cm(-2) and 50 meV red detuning, in good agreement with theory. The energy level structure of the strongly coupled polariton Rabi doublet remains unaffected by the blueshift. The demonstrated effect should allow generation of ultrafast density-independent potentials and imprinting well-defined phase profiles on polariton condensates, providing a powerful tool for manipulation of these condensates, similar to dipole potentials in cold-atom systems.

  11. The Commercial TREMOR Strong-Motion Seismograph

    Science.gov (United States)

    Evans, J. R.; Hamstra, R. H.; Kuendig, C.; Camina, P.

    2001-12-01

    The emergence of major seismological and earthquake-engineering problems requiring large, dense instrument arrays led several of us to investigate alternate solutions. Evans and Rogers (USGS Open File Report 95-555, 1995) and Evans (USGS Open File Report 98-109, 1998) demonstrated the efficacy of low-cost robust silicon accelerometers in strong-motion seismology, making possible a vast increase in the spatial density of such arrays. The 1998 design displays true 16-bit performance and excellent robustness and linearity---13 of these prototype near-real-time instruments are deployed in Oakland, California, and have recorded data from seven small events (up to 5.7 %g). Since this technology is a radical departure from past efforts, it was necessary for the USGS to develop the sensor and demonstrate its efficacy thoroughly. Since it is neither practical nor appropriate for the USGS to produce instrumentation beyond a demonstration phase, the US Geological Survey and GeoSIG Ltd undertook a collaborative effort (a ``CRAD'') to commercialize the new technology. This effort has resulted in a fully temperature-compensated 16-bit system, the GeoSIG GT-316, announced in April, 2001, combining the ICS-3028 TM-based USGS sensor, temperature compensation technique, and peak ground velocity (PGV) computation with a highly customized 16-bit GeoSIG recorder. The price has not been set but is likely to be around \\2000 in large quantities. The result is a near-real-time instrument telemetering peak ground acceleration (PGA) and PGV about 90 s after onset of the P wave, then minutes later transmitting the waveform. The receiving software, ``HomeBase()'', also computes spectral acceleration, S_{a}. PGA, PGV, S_{a}, and waveforms are forwarded immediately by HomeBase() for ShakeMap generation and other uses. Shaking metrics from the prototypes in Oakland are consistently among the first to arrive for the northern California ShakeMap. For telemetry we use a low-cost always

  12. Strong anomalous diffusion of the phase of a chaotic pendulum

    Science.gov (United States)

    Cagnetta, Francesco; Gonnella, Giuseppe; Mossa, Alessandro; Ruffo, Stefano

    2015-07-01

    In this letter we consider the phase diffusion of a harmonically driven undamped pendulum and show that it is anomalous in the strong sense. The role played by the fractal properties of the phase space is highlighted, providing an illustration of the link between deterministic chaos and anomalous transport. Finally, we build a stochastic model which reproduces most properties of the original Hamiltonian system by alternating ballistic flights and random diffusion.

  13. Evidence of strong proton shape fluctuations from incoherent diffraction

    CERN Document Server

    Mäntysaari, Heikki

    2016-01-01

    We show within the saturation framework that measurements of exclusive vector meson production at high energy provide evidence for strong geometric fluctuations of the proton. In comparison, the effect of saturation scale and color charge fluctuations is weak. This knowledge will allow detailed future measurements of the incoherent cross section to tightly constrain the fluctuating geometry of the proton as a function of the parton momentum fraction $x$.

  14. Babesiosis for Health Care Providers

    Centers for Disease Control (CDC) Podcasts

    2012-04-25

    This podcast will educate health care providers on diagnosing babesiosis and providing patients at risk with tick bite prevention messages.  Created: 4/25/2012 by Center for Global Health, Division of Parasitic Diseases and Malaria.   Date Released: 4/25/2012.

  15. HMO partnering: the provider dilemma.

    Science.gov (United States)

    Ayers, J; Benson, L; Bonhag, R

    1996-10-01

    While the growth of HMOs has slowed patient visits to doctors, it also has created a deluge of press clippings. On July 16, 1996, three articles on the subject appeared in the Wall Street Journal, front section. The headlines painted a vivid picture of the forces acting on HMOs and providers alike (Figure 1). The articles portended more change for healthcare. The "shake-out," a term applied to industries in serious transformation, brings shedding of excess capacity and loss of jobs and income. Providers, in particular, find themselves in a difficult dilemma. They must not only cut costs as reimbursement drops, but also retain patients with good outcomes and high quality service. Patient retention means keeping the individual patient from switching to another provider and keeping the insurer's group of patients as an authorized provider for that insurer. The relationship between provider and HMO lies at the heart of the provider dilemma. The HMO structure, which shifts financial risk for care, is quickly setting the standard, for healthcare pricing, medical standards, and management practices. Understanding and responding to HMO needs are vital to competitive advantage and survival. The article discusses the inherent dilemma of HMO and provider partnering and suggests provider responses.

  16. Strong sum distance in fuzzy graphs.

    Science.gov (United States)

    Tom, Mini; Sunitha, Muraleedharan Shetty

    2015-01-01

    In this paper the idea of strong sum distance which is a metric, in a fuzzy graph is introduced. Based on this metric the concepts of eccentricity, radius, diameter, center and self centered fuzzy graphs are studied. Some properties of eccentric nodes, peripheral nodes and central nodes are obtained. A characterisation of self centered complete fuzzy graph is obtained and conditions under which a fuzzy cycle is self centered are established. We have proved that based on this metric, an eccentric node of a fuzzy tree G is a fuzzy end node of G and a node is an eccentric node of a fuzzy tree if and only if it is a peripheral node of G and the center of a fuzzy tree consists of either one or two neighboring nodes. The concepts of boundary nodes and interior nodes in a fuzzy graph based on strong sum distance are introduced. Some properties of boundary nodes, interior nodes and complete nodes are studied.

  17. Effective dynamics of strongly dissipative Rydberg gases

    CERN Document Server

    Marcuzzi, M; Olmos, B; Lesanovsky, I

    2014-01-01

    We investigate the evolution of interacting Rydberg gases in the limit of strong noise and dissipation. Starting from a description in terms of a Markovian quantum master equation we derive effective equations of motion that govern the dynamics on a "coarse-grained" timescale where fast dissipative degrees of freedom have been adiabatically eliminated. Specifically, we consider two scenarios which are of relevance for current theoretical and experimental studies --- Rydberg atoms in a two-level (spin) approximation subject to strong dephasing noise as well as Rydberg atoms under so-called electromagnetically induced transparency (EIT) conditions and fast radiative decay. In the former case we find that the effective dynamics is described by classical rate equations up to second order in an appropriate perturbative expansion. This drastically reduces the computational complexity of numerical simulations in comparison to the full quantum master equation. When accounting for the fourth order correction in this e...

  18. Cosmogenic photons strongly constrain UHECR source models

    CERN Document Server

    van Vliet, Arjen

    2016-01-01

    With the newest version of our Monte Carlo code for ultra-high-energy cosmic ray (UHECR) propagation, CRPropa 3, the flux of neutrinos and photons due to interactions of UHECRs with extragalactic background light can be predicted. Together with the recently updated data for the isotropic diffuse gamma-ray background (IGRB) by Fermi LAT, it is now possible to severely constrain UHECR source models. The evolution of the UHECR sources especially plays an important role in the determination of the expected secondary photon spectrum. Pure proton UHECR models are already strongly constrained, primarily by the highest energy bins of Fermi LAT's IGRB, as long as their number density is not strongly peaked at recent times.

  19. Cosmogenic photons strongly constrain UHECR source models

    Science.gov (United States)

    van Vliet, Arjen

    2017-03-01

    With the newest version of our Monte Carlo code for ultra-high-energy cosmic ray (UHECR) propagation, CRPropa 3, the flux of neutrinos and photons due to interactions of UHECRs with extragalactic background light can be predicted. Together with the recently updated data for the isotropic diffuse gamma-ray background (IGRB) by Fermi LAT, it is now possible to severely constrain UHECR source models. The evolution of the UHECR sources especially plays an important role in the determination of the expected secondary photon spectrum. Pure proton UHECR models are already strongly constrained, primarily by the highest energy bins of Fermi LAT's IGRB, as long as their number density is not strongly peaked at recent times.

  20. Analytical solution of strongly nonlinear Duffing oscillators

    Directory of Open Access Journals (Sweden)

    A.M. El-Naggar

    2016-06-01

    Full Text Available In this paper, a new perturbation technique is employed to solve strongly nonlinear Duffing oscillators, in which a new parameter α=α(ε is defined such that the value of α is always small regardless of the magnitude of the original parameter ε. Therefore, the strongly nonlinear Duffing oscillators with large parameter ε are transformed into a small parameter system with respect to α. Approximate solution obtained by the present method is compared with the solution of energy balance method, homotopy perturbation method, global error minimization method and lastly numerical solution. We observe from the results that this method is very simple, easy to apply, and gives a very good accuracy not only for small parameter εbut also for large values of ε.

  1. Strong curvature effects in Neumann wave problems

    DEFF Research Database (Denmark)

    Willatzen, Morten; Pors, A.; Gravesen, Jens

    2012-01-01

    equation for a quantum-mechanical particle confined by infinite barriers relevant in semiconductor physics. With this in mind and the interest to tailor waveguides towards a desired spectrum and modal pattern structure in classical structures and nanostructures, it becomes increasingly important...... to understand the influence of curvature effects in waveguides. In this work, we demonstrate analytically strong curvature effects for the eigenvalue spectrum of the Helmholtz equation with Neumann boundary conditions in cases where the waveguide cross section is a circular sector. It is found that the linear......-in-curvature contribution originates from parity symmetry breaking of eigenstates in circular-sector tori and hence vanishes in a torus with a complete circular cross section. The same strong curvature effect is not present in waveguides subject to Dirichlet boundary conditions where curvature contributions contribute...

  2. Cosmogenic photons strongly constrain UHECR source models

    Directory of Open Access Journals (Sweden)

    van Vliet Arjen

    2017-01-01

    Full Text Available With the newest version of our Monte Carlo code for ultra-high-energy cosmic ray (UHECR propagation, CRPropa 3, the flux of neutrinos and photons due to interactions of UHECRs with extragalactic background light can be predicted. Together with the recently updated data for the isotropic diffuse gamma-ray background (IGRB by Fermi LAT, it is now possible to severely constrain UHECR source models. The evolution of the UHECR sources especially plays an important role in the determination of the expected secondary photon spectrum. Pure proton UHECR models are already strongly constrained, primarily by the highest energy bins of Fermi LAT’s IGRB, as long as their number density is not strongly peaked at recent times.

  3. Distance Duality Relation from Strong Gravitational Lensing

    CERN Document Server

    Liao, Kai; Cao, Shuo; Biesiada, Marek; Zheng, Xiaogang; Zhu, Zong-Hong

    2015-01-01

    Under very general assumptions of metric theory of spacetime, photons traveling along null geodesics and photon number conservation, two observable concepts of cosmic distance, i.e. the angular diameter and the luminosity distances are related to each other by the so called distance duality relation (DDR) $D^L=D^A(1+z)^2$. Observational validation of this relation is quite important because any evidence of its violation could be a signal of new physics. In this letter we introduce a new method to test DDR based on strong gravitational lensing systems and supernovae Ia. Using a new compilation of strong lensing systems and JLA compilation of SNe Ia we found no evidence of DDR violation. However, not so much the final result but the method itself is worth attention, because unlike previously proposed techniques, it does not depend on prior assumptions concerning the details of cosmological model and galaxy cluster modelling.

  4. Model reduction of strong-weak neurons.

    Science.gov (United States)

    Du, Bosen; Sorensen, Danny; Cox, Steven J

    2014-01-01

    We consider neurons with large dendritic trees that are weakly excitable in the sense that back propagating action potentials are severly attenuated as they travel from the small, strongly excitable, spike initiation zone. In previous work we have shown that the computational size of weakly excitable cell models may be reduced by two or more orders of magnitude, and that the size of strongly excitable models may be reduced by at least one order of magnitude, without sacrificing the spatio-temporal nature of its inputs (in the sense we reproduce the cell's precise mapping of inputs to outputs). We combine the best of these two strategies via a predictor-corrector decomposition scheme and achieve a drastically reduced highly accurate model of a caricature of the neuron responsible for collision detection in the locust.

  5. Strongly Coupled Quark Gluon Plasma (SCQGP)

    CERN Document Server

    Bannur, V M

    2006-01-01

    We propose that the reason for the non-ideal behavior seen in lattice simulation of quark gluon plasma (QGP) and relativistic heavy ion collisions (URHICs) experiments is that the QGP near T_c and above is strongly coupled plasma (SCP), i.e., strongly coupled quark gluon plasma (SCQGP). It is remarkable that the widely used equation of state (EoS) of SCP in QED (quantum electrodynamics) very nicely fits lattice results on all QGP systems, with proper modifications to include color degrees of freedom and running coupling constant. Results on pressure in pure gauge, 2-flavors and 3-flavors QGP, are all can be explained by treating QGP as SCQGP as demonstated here.Energy density and speed of sound are also presented for all three systems.

  6. Frictional Coulomb drag in strong magnetic fields

    DEFF Research Database (Denmark)

    Bønsager, Martin Christian; Flensberg, Karsten; Hu, Ben Yu-Kuang;

    1997-01-01

    A treatment of frictional Coulomb drag between two two-dimensional electron layers in a strong perpendicular magnetic field, within the independent electron picture, is presented. Assuming fully resolved Landau levels, the linear response theory expression for the transresistivity rho(21) is eval......A treatment of frictional Coulomb drag between two two-dimensional electron layers in a strong perpendicular magnetic field, within the independent electron picture, is presented. Assuming fully resolved Landau levels, the linear response theory expression for the transresistivity rho(21......) is evaluated using diagrammatic techniques. The transresistivity is given by an integral over energy and momentum transfer weighted by the product of the screened interlayer interaction and the phase space for scattering events. We demonstrate, by a numerical analysis of the transresistivity, that for well...

  7. Nonperturbative enhancement of superloop at strong coupling

    Science.gov (United States)

    Belitsky, A. V.

    2016-10-01

    We address the near-collinear expansion of NMHV six-particle scattering amplitudes at strong value of the 't Hooft coupling in planar maximally supersymmetric Yang-Mills theory. We complement recent studies of this observable within the context of the Pentagon Operator Product Expansion, via the dual superWilson loop description, by studying effects of multiple scalar exchanges that accompany (or not) massive flux-tube excitations. Due to the fact that holes have a very small, nonperturbatively generated mass mh which is exponentially suppressed in the 't Hooft coupling, their exchanges must be resummed in the ultraviolet limit, τ ≪ 1 /mh. This procedure yields a contribution to the expectation value of the superloop which enters on equal footing with the classical area - a phenomenon which was earlier observed for MHV amplitudes. In all components, the near-massless scalar exchanges factorize from the ones of massive particles, at leading order in strong coupling.

  8. Strong side of weak topological insulators

    Science.gov (United States)

    Ringel, Zohar; Kraus, Yaacov E.; Stern, Ady

    2012-07-01

    Three-dimensional topological insulators are classified into “strong” (STI) and “weak” (WTI) according to the nature of their surface states. While the surface states of the STI are topologically protected from localization, this does not hold for the WTI. In this work, we show that the surface states of the WTI are actually protected from any random perturbation that does not break time-reversal symmetry, and does not close the bulk energy gap. Consequently, the conductivity of metallic surfaces in the clean system remains finite even in the presence of strong disorder of this type. In the weak disorder limit, the surfaces are found to be perfect metals, and strong surface disorder only acts to push the metallic surfaces inwards. We find that the WTI differs from the STI primarily in its anisotropy, and that the anisotropy is not a sign of its weakness but rather of its richness.

  9. Nonperturbative enhancement of superloop at strong coupling

    CERN Document Server

    Belitsky, A V

    2015-01-01

    We address the near-collinear expansion of NMHV six-particle scattering amplitudes at strong value of 't Hooft coupling in planar maximally supersymmetric Yang-Mills theory. We complement recent studies of this observable within the context of the pentagon operator product expansion, via the dual super Wilson loop description, by studying effects of multiple scalar exchanges that accompany (or not) massive flux-tube excitations. Due to the fact that holes have a very small, nonperturbatively generated mass which is exponentially suppressed in 't Hooft coupling, their exchanges must be resummed in the ultraviolet limit. This procedure yields a contribution to the expectation value of the superloop which enters on equal footing with the classical area, --- a phenomenon which was earlier observed for MHV amplitudes. In all components, the near-massless scalar exchanges factorize from the ones of massive particles, at leading order in strong coupling.

  10. Peltier effect in strongly driven quantum wires

    Science.gov (United States)

    Mierzejewski, M.; Crivelli, D.; Prelovšek, P.

    2014-08-01

    We study a microscopic model of a thermocouple device with two connected correlated quantum wires driven by a constant electric field. In such a closed system we follow the time and position dependence of the entropy density using the concept of the reduced density matrix. At weak driving, the initial changes of the entropy at the junctions can be described by the linear Peltier response. At longer times the quasiequilibrium situation is reached with well defined local temperatures which increase due to an overall Joule heating. On the other hand, a strong electric field induces a nontrivial nonlinear thermoelectric response, e.g., the Bloch oscillations of the energy current. Moreover, we show for the doped Mott insulators that strong driving can reverse the Peltier effect.

  11. Nonlinear waves in strongly interacting relativistic fluids

    CERN Document Server

    Fogaça, D A; Filho, L G Ferreira

    2013-01-01

    During the past decades the study of strongly interacting fluids experienced a tremendous progress. In the relativistic heavy ion accelerators, specially the RHIC and LHC colliders, it became possible to study not only fluids made of hadronic matter but also fluids of quarks and gluons. Part of the physics program of these machines is the observation of waves in this strongly interacting medium. From the theoretical point of view, these waves are often treated with li-nearized hydrodynamics. In this text we review the attempts to go beyond linearization. We show how to use the Reductive Perturbation Method to expand the equations of (ideal and viscous) relativistic hydrodynamics to obtain nonlinear wave equations. These nonlinear wave equations govern the evolution of energy density perturbations (in hot quark gluon plasma) or baryon density perturbations (in cold quark gluon plasma and nuclear matter). Different nonlinear wave equations, such as the breaking wave, Korteweg-de Vries and Burgers equations, are...

  12. Gallstone ileus resulting in strong intestinal obstruction

    Directory of Open Access Journals (Sweden)

    Israel Szajnbok

    Full Text Available Mechanic intestinal obstruction, caused by the passage of biliary calculus from vesicle to intestine, through fistulization, although not frequent, deserve study due to the morbi-mortality rates. Incidence in elder people explains the association with chronic degenerative diseases, increasing complexity in terms of therapy decision. Literature discusses the need and opportunity for the one or two-phase surgical attack of the cholecystenteric fistule, in front of the resolution on the obstructive urgency and makes reference to Gallstone Ileus as an exception for strong intestinal obstruction. The more frequent intestinal obstruction observed is when it occurs a Gallstone Ileus impacting in terms of ileocecal valve. The authors submit a Gallstone Ileus manifestation as causing strong intestinal obstruction, discussing aspects regarding diagnostic and treatment.

  13. Weakly and Strongly Regular Near-rings

    Institute of Scientific and Technical Information of China (English)

    N.Argac; N.J.Groenewald

    2005-01-01

    In this paper, we prove some basic properties of left weakly regular near-rings.We give an affirmative answer to the question whether a left weakly regular near-ring with left unity and satisfying the IFP is also right weakly regular. In the last section, we use among others left 0-prime and left completely prime ideals to characterize strongly regular near-rings.

  14. Quantum states with strong positive partial transpose

    Science.gov (United States)

    Chruściński, Dariusz; Jurkowski, Jacek; Kossakowski, Andrzej

    2008-02-01

    We construct a large class of bipartite M⊗N quantum states which defines a proper subset of states with positive partial transposes (PPTs). Any state from this class has PPT but the positivity of its partial transposition is recognized with respect to canonical factorization of the original density operator. We propose to call elements from this class states with strong positive partial transposes (SPPTs). We conjecture that all SPPT states are separable.

  15. The "hard" problem of strong of interactions

    CERN Document Server

    Neuberger, Herbert

    2010-01-01

    This is a write-up of a lecture at the level of a physics colloquium. There exists an idealized mathematical formulation of strong interactions which has no free parameters but is known to describe the real world quite accurately. Over the last three decades the problem has been managed with increasing success. An overview of some facts and a little fiction will be presented, but the question whether the problem can now be considered "easy" will be left unanswered.

  16. Strongly stable real infinitesimally symplectic mappings

    NARCIS (Netherlands)

    Cushman, R.; Kelley, A.

    1979-01-01

    We prove that a mapA εsp(σ,R), the set of infinitesimally symplectic maps, is strongly stable if and only if its centralizerC(A) insp(σ,R) contains only semisimple elements. Using the theorem that everyB insp(σ,R) close toA is conjugate by a real symplectic map to an element ofC(A), we give a new pr

  17. Strong cosmic censorship and Misner spacetime

    CERN Document Server

    Denaro, Pedro

    2015-01-01

    Misner spacetime is among the simplest solutions of Einstein's equation that exhibits a Cauchy horizon with a smooth extension beyond it. Besides violating strong cosmic censorship, this extension contains closed timelike curves. We analyze the stability of the Cauchy horizon, and prove that neighboring spacetimes in one parameter families of solutions through Misner's in pure gravity, gravity coupled to a scalar field, or Einstein-Maxwell theory, end at the Cauchy horizon developing a curvature singularity.

  18. The STRONG STAR Multidisciplinary PTSD Research Consortium

    Science.gov (United States)

    2013-09-01

    myocardial infarction and pre- dicting variables. J. Psychosom. Res. 69, 143e150. Harvey, B.H., Brand, L., Jeeva, Z., Stein, D.J., 2006. Cortical...For the STRONG STAR Consortium. Available online at www.sciencedirect.com j our na l h omepa g e: www.e l se v ie r.c om /l oca te/ psyne ue n 0306

  19. Analytic Solution of Strongly Coupling Schroedinger Equation

    CERN Document Server

    Liao, J Y; Liao, Jinfeng; Zhuang, Pengfei

    2002-01-01

    The recently developed expansion method for ground states of strongly coupling Schr\\"odinger equations by Friedberg, Lee and Zhao is extended to excited states. The coupling constant dependence of bound states for power-law central forces $V(r) \\propto g^k r^n$ is particularly studied. With the extended method all the excited states of the Hydrogen atom problem are resolved and the low-lying states for Yukawa potential are approximately obtained.

  20. Kinks: Fingerprints of strong electronic correlations

    Energy Technology Data Exchange (ETDEWEB)

    Toschi, A; Held, K [Institut fuer Festkoerperphysik, Technische Universitaet Wien, Vienna (Austria); Capone, M; Castellani, C, E-mail: held@ifp.tuwien.ac.a [SMC, CNR-INFM and Dipartimento di Fisica - Universita di Roma ' La Sapienza' , Piazzale Aldo Moro 2, 00185 Roma (Italy)

    2010-01-15

    The textbook knowledge of solid state physics is that the electronic specific heat shows a linear temperature dependence with the leading corrections being a cubic term due to phonons and a cubic-logarithmic term due to the interaction of electrons with bosons. We have shown that this longstanding conception needs to be supplemented since the generic behavior of the low-temperature electronic specific heat includes a kink if the electrons are sufficiently strongly correlated.

  1. Strong energy condition and the fastest computer

    CERN Document Server

    Yang, Run-Qiu

    2016-01-01

    This paper shows holographic complexity-action (CA) conjecture is inconsistent with the theory about complexity growth bound in general if we don't make any restriction on matter fields. For a static black hole with topology $R^2\\times S^2$ and some general conditions, it shows that, if matter fields are steady outside of Killing horizon, strong energy condition is a sufficient condition to insure that vacuum black holes have the fastest holographic complexity growth.

  2. Strongly Scale-dependent Non-Gaussianity

    CERN Document Server

    Riotto, Antonio

    2011-01-01

    We discuss models of primordial density perturbations where the non-Gaussianity is strongly scale-dependent. In particular, the non-Gaussianity may have a sharp cut-off and be very suppressed on large cosmological scales, but sizeable on small scales. This may have an impact on probes of non-Gaussianity in the large-scale structure and in the cosmic microwave background radiation anisotropies.

  3. SUSY strong production (leptonic) with ATLAS

    CERN Document Server

    Saito, Tomoyuki; The ATLAS collaboration

    2017-01-01

    Supersymmetry is one of the most motivated scenarios for physics beyond the Standard Model. This article summarizes recent ATLAS results on searches for supersymmetry in proton-proton collisions at a centre-of-mass energy of 13 TeV at LHC, which target supersymmetric particles produced by strong interaction in events with leptonic fi nal states. No signi ficant excess above the Standard Model expectation is observed and exclusion limits have been set on squark and gluino masses in various scenarios.

  4. Symplectic cobordisms and the strong Weinstein conjecture

    OpenAIRE

    GEIGES, Hansjörg; Zehmisch, Kai

    2011-01-01

    We study holomorphic spheres in certain symplectic cobordisms and derive information about periodic Reeb orbits in the concave end of these cobordisms from the non-compactness of the relevant moduli spaces. We use this to confirm the strong Weinstein conjecture (predicting the existence of null-homologous Reeb links) for various higher-dimensional contact manifolds, including contact type hypersurfaces in subcritical Stein manifolds and in some cotangent bundles. The quantitative character of...

  5. Strong CP and SUZ{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Albaid, Abdelhamid [Department of Diagnostic Radiology, University of Hail,Alsawamea Street, Hail (Saudi Arabia); Dine, Michael [Santa Cruz Institute for Particle Physics and Department of Physics,University of California, High Street, Santa Cruz, CA 93106 (United States); Draper, Patrick [Department of Physics, University of California,Santa Barbara, CA 93106 (United States); Santa Cruz Institute for Particle Physics and Department of Physics,University of California, High Street, Santa Cruz, CA 93106 (United States)

    2015-12-09

    Solutions to the strong CP problem typically introduce new scales associated with the spontaneous breaking of symmetries. Absent any anthropic argument for small θ̄, these scales require stabilization against ultraviolet corrections. Supersymmetry offers a tempting stabilization mechanism, since it can solve the “big' electroweak hierarchy problem at the same time. One family of solutions to strong CP, including generalized parity models, heavy axion models, and heavy η{sup ′} models, introduces ℤ{sub 2} copies of (part of) the Standard Model and an associated scale of ℤ{sub 2}-breaking. We review why, without additional structure such as supersymmetry, the ℤ{sub 2}-breaking scale is unacceptably tuned. We then study “SUZ{sub 2}' models, supersymmetric theories with ℤ{sub 2} copies of the MSSM. We find that the addition of SUSY typically destroys the ℤ{sub 2} protection of θ̄=0, even at tree level, once SUSY and ℤ{sub 2} are broken. In theories like supersymmetric completions of the twin Higgs, where ℤ{sub 2} addresses the little hierarchy problem but not strong CP, two axions can be used to relax θ̄.

  6. Photoelectron spectroscopy of strongly correlated Yb compounds

    Energy Technology Data Exchange (ETDEWEB)

    Joyce, J.J.; Andrews, A.B.; Arko, A.J.; Bartlett, R.J.; Blythe, R.I. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Olson, C.G.; Benning, P.J.; Canfield, P.C. [Ames Laboratory, U. S. Department of Energy, Ames, Iowa 50011 (United States); Poirier, D.M. [Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    1996-12-01

    The electronic properties of the Yb compounds YBCu{sub 2}Si{sub 2}, YBAgCu{sub 4}, and YbAl{sub 3} along with purely divalent Yb metal, have been investigated by means of high-resolution ultraviolet and x-ray photoelectron spectroscopy. We present the intrinsic characteristic features of the 4{ital f} levels of Yb while accounting for lattice vibrations and the manifestation of corelike energy levels degenerate with the valence states and modified by the temperature-dependent Fermi function. For these strongly correlated Yb-based compounds, the hole occupancy values ({ital n}{sub {ital f}}{approximately}0.6) directly obtained from integration of the divalent and trivalent portions of the 4{ital f} photoemission features indicate that these compounds are strongly mixed valent. The small intensity modulation with temperature in the divalent Yb 4{ital f} levels (0{endash}10{percent} over a {ital T}=20{minus}300 K range) is discussed within the conventional framework of the photoemission process and nominal allowances for lattice variations with temperature. Results from photoemission experiments on the divalent 4{ital f} levels of strongly correlated Yb compounds are remarkably similar to the 4{ital f} levels of purely divalent Yb metal. {copyright} {ital 1996 The American Physical Society.}

  7. Inflationary magnetogenesis without the strong coupling problem

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Ricardo J.Z.; Jain, Rajeev Kumar; Sloth, Martin S., E-mail: ferreira@cp3.dias.sdu.dk, E-mail: jain@cp3.dias.sdu.dk, E-mail: sloth@cp3.dias.sdu.dk [CP3-Origins, Centre for Cosmology and Particle Physics Phenomenology, University of Southern Denmark, Campusvej 55, 5230 Odense M (Denmark)

    2013-10-01

    The simplest gauge invariant models of inflationary magnetogenesis are known to suffer from the problems of either large backreaction or strong coupling, which make it difficult to self-consistently achieve cosmic magnetic fields from inflation with a field strength larger than 10{sup −32}G today on the Mpc scale. Such a strength is insufficient to act as seed for the galactic dynamo effect, which requires a magnetic field larger than 10{sup −20}G. In this paper we analyze simple extensions of the minimal model, which avoid both the strong coupling and back reaction problems, in order to generate sufficiently large magnetic fields on the Mpc scale today. First we study the possibility that the coupling function which breaks the conformal invariance of electromagnetism is non-monotonic with sharp features. Subsequently, we consider the effect of lowering the energy scale of inflation jointly with a scenario of prolonged reheating where the universe is dominated by a stiff fluid for a short period after inflation. In the latter case, a systematic study shows upper bounds for the magnetic field strength today on the Mpc scale of 10{sup −13}G for low scale inflation and 10{sup −25}G for high scale inflation, thus improving on the previous result by 7-19 orders of magnitude. These results are consistent with the strong coupling and backreaction constraints.

  8. Towards gauge unified, supersymmetric hidden strong dynamics

    CERN Document Server

    Chiang, Cheng-Wei; Ye, Fang

    2016-01-01

    We consider a class of models with extra complex scalars that are charged under both the Standard Model and a hidden strongly coupled $SU(N)_H$ gauge sector, and discuss the scenarios where the new scalars are identified as the messenger fields that mediate the spontaneously broken supersymmetries from the hidden sector to the visible sector. The new scalars are embedded into 5-plets and 10-plets of an $SU(5)_V$ gauge group that potentially unifies the Standard Model gauge groups. They also form a tower of bound states via hidden strong dynamics around the TeV scale. The Higgs bosons remain as elementary particles. Quadratically divergent contributions to the Higgs mass from the Standard Model fermions are canceled by the new scalar contributions to alleviate the fine-tuning problem. We also discuss a supersymmetrized version of this class of models, consisting of the minimal supersymmetric Standard Model plus extra chiral multiplets where the new scalars reside. Due to the hidden strong force, the new low-en...

  9. Cosmological test using strong gravitational lensing systems

    CERN Document Server

    Yuan, C C

    2015-01-01

    As one of the probes of universe, strong gravitational lensing systems allow us to compare different cosmological models and constrain vital cosmological parameters. This purpose can be reached from the dynamic and geometry properties of strong gravitational lensing systems, for instance, time-delay $\\Delta\\tau$ of images, the velocity dispersion $\\sigma$ of the lensing galaxies and the combination of these two effects, $\\Delta\\tau/\\sigma^2$. In this paper, in order to carry out one-on-one comparisons between $\\Lambda$CDM universe and $R_h=ct$ universe, we use a sample containing 36 strong lensing systems with the measurement of velocity dispersion from the SLACS and LSD survey. Concerning the time-delay effect, 12 two-image lensing systems with $\\Delta\\tau$ are also used. In addition, Monte Carlo (MC) simulations are used to compare the efficiency of the three methods as mentioned above. From simulations, we estimate the number of lenses required to rule out one model at the $99.7\\%$ confidence level. Compar...

  10. Strong Tides in 1964 and 1982

    Institute of Scientific and Technical Information of China (English)

    Dianyou Chen; Xuexiang Yang; Qiyuan Qiao

    2003-01-01

    The differential rotation between solid and fluid caused by tidal force can explain a 1500 to 1800-year cycle of the climate change. Strong tide increases the vertical and horizontal mixing of water in ocean by drawing the cold Pacific water from the depths to the surface (or by making the warm water flow from the West Pacific to the East as well as from the North to the South). It cools or warms the atmosphere above and makes La Nina or El Nino occur in the whole world. Astronomical data have shown that strong tide is often associated with El Nino events. Volcanic activities at submarine are also controlled by strong tide. Volcanic activities can also draw warm water from the depths to the surface in the Pacific and volcanic ash can keep out sunlight, which is the most important external forcing factor for El Nino. If volcanic ash reaches into the stratosphere, finer aerosols will spread throughout the globe during a few months and will float in it for one to three years to weaken the sun's direct radiation to the areas. It is one of the factors to postpone EI Nino just like the process of solar eclipse.

  11. Recovery-promoting professional competencies: perspectives of mental health consumers, consumer-providers and providers.

    Science.gov (United States)

    Russinova, Zlatka; Rogers, E Sally; Ellison, Marsha Langer; Lyass, Asya

    2011-01-01

    The purpose of this study was to empirically validate a set of conceptually derived recovery-promoting competencies from the perspectives of mental health consumers, consumer-providers and providers. A national sample of 603 consumers, 153 consumer-providers and 239 providers completed an anonymous survey via the Internet. The survey evaluated respondents' perceptions about a set of 37 competencies hypothesized to enhance clients' hope and empowerment and inquired about interactions with providers that enhanced clients' recovery process. We used descriptive statistics and ranking to establish the relevance of each competency and generalized linear models and post-hoc tests to examine differences in the consumers', consumer-providers' and providers' assessments of these competencies. Analyses confirmed the recovery relevance of several competencies and their relative importance within each group of study participants. They also revealed that while most competencies tended to have universal significance, others depended more strongly on the client's preferences. Finally, differences in the perceptions of consumers, consumer-providers and providers about the recovery relevance of these competencies were established. The study highlighted the crucial role practitioners play in enhancing recovery from serious mental illnesses through specific strategies and attitudes that acknowledge clients' personhood and foster their hopefulness, empowerment and illness management. It informed the development of a new instrument measuring providers' recovery-promoting competence and provides guidelines for sharpening the recovery focus of a wide range of mental health and rehabilitation services.

  12. Hospitals, providers collaborate on transitions.

    Science.gov (United States)

    2012-01-01

    Baystate Health, a three-hospital system with headquarters in Springfield, MA, is partnering with post-acute providers to improve transitions as patients move through the continuum of care. A multidisciplinary post-acute performance team partnered with post-acute providers to determine why patients are readmitted to the hospital and to work on ways to avoid readmissions. Facilities share information with the hospitals how they operate and what they need to ensure patients receive the care they need. The health system's director of post-acute services holds regular meetings with providers to brainstorm on improving patient care.

  13. Engaging Military Fathers in a Reflective Parenting Program: Lessons from Strong Families Strong Forces

    Science.gov (United States)

    DeVoe, Ellen R.; Paris, Ruth

    2015-01-01

    Through Strong Families Strong Forces, a reflective parenting program for military families with young children, we were privileged to work with contemporary military fathers who served in the post-9/11 conflicts in Afghanistan and Iraq. Due to this work, the authors gained valuable insight into the complexity of fathering during wartime, the…

  14. Gutzwiller approximation in strongly correlated electron systems

    Science.gov (United States)

    Li, Chunhua

    Gutzwiller wave function is an important theoretical technique for treating local electron-electron correlations nonperturbatively in condensed matter and materials physics. It is concerned with calculating variationally the ground state wave function by projecting out multi-occupation configurations that are energetically costly. The projection can be carried out analytically in the Gutzwiller approximation that offers an approximate way of calculating expectation values in the Gutzwiller projected wave function. This approach has proven to be very successful in strongly correlated systems such as the high temperature cuprate superconductors, the sodium cobaltates, and the heavy fermion compounds. In recent years, it has become increasingly evident that strongly correlated systems have a strong propensity towards forming inhomogeneous electronic states with spatially periodic superstrutural modulations. A good example is the commonly observed stripes and checkerboard states in high- Tc superconductors under a variety of conditions where superconductivity is weakened. There exists currently a real challenge and demand for new theoretical ideas and approaches that treats strongly correlated inhomogeneous electronic states, which is the subject matter of this thesis. This thesis contains four parts. In the first part of the thesis, the Gutzwiller approach is formulated in the grand canonical ensemble where, for the first time, a spatially (and spin) unrestricted Gutzwiller approximation (SUGA) is developed for studying inhomogeneous (both ordered and disordered) quantum electronic states in strongly correlated electron systems. The second part of the thesis applies the SUGA to the t-J model for doped Mott insulators which led to the discovery of checkerboard-like inhomogeneous electronic states competing with d-wave superconductivity, consistent with experimental observations made on several families of high-Tc superconductors. In the third part of the thesis, new

  15. Narratives of Ghanaian abortion providers

    African Journals Online (AJOL)

    AJRH Managing Editor

    Keywords: Abortion, providers, law, access, reproductive health care ... administrative materials) into the decision-making process between a ... training, research, and outreach efforts of these ..... additional economic factors influence abortion.

  16. TERRAIN, PROVIDENCE COUNTY, RHODE ISLAND

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Providence AOI consists of the costal portion of the county, and meshes up seamlessly with the Kent county AOI directly south. Ground Control is collected...

  17. Medicare Referring Provider DMEPOS PUF

    Data.gov (United States)

    U.S. Department of Health & Human Services — This dataset, which is part of CMSs Medicare Provider Utilization and Payment Data, details information on Durable Medical Equipment, Prosthetics, Orthotics and...

  18. Lodging Update: Providence, Rhode Island

    Directory of Open Access Journals (Sweden)

    Ragel Roginsky

    2013-04-01

    Full Text Available Each quarter, Pinnacle Advisory Group prepares an analysis of the New England lodging industry, which provides a regional summary and then focuses in depth on a particular market. These reviews look at recent and proposed supply changes, factors affecting demand and growth rates, and the effects of interactions between such supply and demand trends. In this issue, the authors spotlight the lodging market in Providence, Rhode Island.

  19. Single Site Strong-Motion Attenuation Relationship

    Science.gov (United States)

    Sung, C.; Lee, C.

    2009-12-01

    The standard deviation of the logarithmic residuals in ground-motion prediction may directly influence the result of probabilistic seismic hazard analysis, especially in low probability. Therefore, “how to reduce the σ?” becomes an important issue in recent years. In most modern empirical ground motion studies, the total variability was separated into inter-event and intra-event components to distinction between epistemic uncertainty and aleatory uncertainty. Another approach is gaining control over the value of σ is to investigate in more detail the behavior of the individual components of variability with a single event or a single station (e.g., Niazi and Bozorgnia 1991; Ordaz and Reyes 1999; Jain et al. 2000; Atkinson 2006; Morikawa et al (2008)). In this study, we use the large data set available from the Taiwan Strong Motion Instrumentation Program (TSMIP) and select stations which recorded more than 700 strong-motion records (six stations). The ground motion attenuation is modified based on Campbell form which includes source term, distance term and site term Vs30. It is worth noting that a single site strong motion attenuation model does not include the site term, because the site is fixed at a station. Finally, we use hemisphere projection to show the path effect of residual in this study and compare the standard deviation for a single station (σi) and total stations (σT). We find that the single-station standard deviation is 20% smaller than the total standard deviation in this study and the result is better than Atkinson (2006). In the future work, a single source-region where occurred more than 5 earthquakes which triggered more than 50 stations will be selected for single source-region attenuation study.

  20. Ancillary Services Provided from DER

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, J.B.

    2005-12-21

    Distributed energy resources (DER) are quickly making their way to industry primarily as backup generation. They are effective at starting and then producing full-load power within a few seconds. The distribution system is aging and transmission system development has not kept up with the growth in load and generation. The nation's transmission system is stressed with heavy power flows over long distances, and many areas are experiencing problems in providing the power quality needed to satisfy customers. Thus, a new market for DER is beginning to emerge. DER can alleviate the burden on the distribution system by providing ancillary services while providing a cost adjustment for the DER owner. This report describes 10 types of ancillary services that distributed generation (DG) can provide to the distribution system. Of these 10 services the feasibility, control strategy, effectiveness, and cost benefits are all analyzed as in the context of a future utility-power market. In this market, services will be provided at a local level that will benefit the customer, the distribution utility, and the transmission company.

  1. Ecosystem services provided by waterbirds.

    Science.gov (United States)

    Green, Andy J; Elmberg, Johan

    2014-02-01

    Ecosystem services are ecosystem processes that directly or indirectly benefit human well-being. There has been much recent literature identifying different services and the communities and species that provide them. This is a vital first step towards management and maintenance of these services. In this review, we specifically address the waterbirds, which play key functional roles in many aquatic ecosystems, including as predators, herbivores and vectors of seeds, invertebrates and nutrients, although these roles have often been overlooked. Waterbirds can maintain the diversity of other organisms, control pests, be effective bioindicators of ecological conditions, and act as sentinels of potential disease outbreaks. They also provide important provisioning (meat, feathers, eggs, etc.) and cultural services to both indigenous and westernized societies. We identify key gaps in the understanding of ecosystem services provided by waterbirds and areas for future research required to clarify their functional role in ecosystems and the services they provide. We consider how the economic value of these services could be calculated, giving some examples. Such valuation will provide powerful arguments for waterbird conservation.

  2. Chiral transition in a strong magnetic background

    CERN Document Server

    Fraga, Eduardo S

    2008-01-01

    The presence of a strong magnetic background can modify the nature and the dynamics of the chiral phase transition at finite temperature. We compute the modified effective potential in the linear sigma model with quarks to one loop in the $\\bar{MS}$ scheme for $N_{f}=2$. For fields $eB\\sim 5 m_{\\pi}^{2}$ and larger a crossover is turned into a weak first-order transition. We discuss possible implications for non-central heavy ion collisions at RHIC and LHC, and for the primordial QCD transition.

  3. Discovering Strong Top Dynamics at the LHC

    CERN Document Server

    Chivukula, R Sekhar; Ittisamai, Pawin; Logan, Heather E; Martin, Adam; Ren, Jing; Simmons, Elizabeth H

    2012-01-01

    We analyze the phenomenology of the top-pion and top-Higgs states in models with strong top dynamics, and translate the present LHC constraints on the SM Higgs into bounds on these scalar states. We then present the discovery prospects for top-pions and top-Higgs at the LHC in the available parameter space by doing a detailed signal/background analysis. We explore the possibility that the potential Higgs signal at a mass of approximately 125 GeV observed at the LHC is consistent with a neutral pseudoscalar top-pion state.

  4. Weak, strong, and uniform quantum simulations

    Science.gov (United States)

    Wang, Dong-Sheng

    2015-01-01

    In this work, we introduce different types of quantum simulations according to different operator topologies on a Hilbert space, namely, uniform, strong, and weak quantum simulations. We show that they have the same computational power that the efficiently solvable problems are in bounded-error quantum polynomial time. For the weak simulation, we formalize a general weak quantum simulation problem and construct an algorithm which is valid for all instances. Also, we analyze the computational power of quantum simulations by proving the query lower bound for simulating a general quantum process.

  5. Sheath Structures of Strongly Electronegative Plasmas

    Institute of Scientific and Technical Information of China (English)

    段萍; 王正汹; 王文春; 刘金远; 刘悦; 王晓钢

    2005-01-01

    The sheath structures of strongly electronegative plasmas are investigated on basis of the accurate Bohm criterion obtained by Sagdeev potential. It is found that the presheath transition between the bulk plasma and the sheath almost does not exist there, and that distributions of electrons, negative and positive ions in the sheath form a pure positive ion sheath near the boundary of the electrode. Furthermore, the density distribution of space net charge has a peak near the sheath edge, the spatial potential within the sheath falls faster, and the sheath thickness becomes thinner.

  6. Strong Mills-Nixon effect in biphenylene

    Science.gov (United States)

    Eckert-Maksić, M.; Hodošček, M.; Kovaček, D.; Maksić, Z. B.; Poljanec, K.

    1990-07-01

    Structural features of biphenylene are studied by semiempirical and ab initio SCF methods employing STO-3G, 3-21G and 6-31G basis sets. The latter gives results in very good agreement with the X-ray data. The distribution of bond distances reveals the presence of a strong Mills—Nixon effect which has been questioned many times in similar systems. The origin of the highly pronounced Mills—Nixon effect is analyzed. It is found that it arises due to concerted and synergistic action of σ- and Π-electrons which leads to Mills—Nixon type of bond fixation.

  7. Strong interaction at finite temperature

    Indian Academy of Sciences (India)

    S Mallik

    2003-11-01

    We review two methods discussed in the literature to determine the effective parameters of strongly interacting particles as they move through a heat bath. The first one is the general method of chiral perturbation theory, which may be readily applied to this problem. The other is the method of thermal QCD sum rules. We show that, when the spectral sides of the sum rules are calculated correctly, they do not lead to any new results, but reproduce those of the vacuum sum rules.

  8. Strong coupling effective theory with heavy fermions

    CERN Document Server

    Fromm, Michael; Lottini, Stefano; Philipsen, Owe

    2011-01-01

    We extend the recently developed strong coupling, dimensionally reduced Polyakov-loop effective theory from finite-temperature pure Yang-Mills to include heavy fermions and nonzero chemical potential by means of a hopping parameter expansion. Numerical simulation is employed to investigate the weakening of the deconfinement transition as a function of the quark mass. The tractability of the sign problem in this model is exploited to locate the critical surface in the (M/T, mu/T, T) space over the whole range of chemical potentials from zero up to infinity.

  9. Why so strong for the lotus leaf?

    Science.gov (United States)

    Guo, Zhiguang; Liu, Weimin; Su, Bao-Lian

    2008-11-01

    The authors discussed the potential reasons why the lotus leaf is so strong by means of scanning electron microscopy (SEM). The results showed that the good mechanical properties of lotus leaf should be attributed to its architecture, such as paralleled microtubes structure, umbrellalike structure, and hierarchically layered hexagon structure. The important observation from this work is that the surface of the rear face of the lotus leaf seems to be constituted by the layers of hexagons whose hierarchical pilling up of size decreases as we go deeper from surface. This is a typical fractal-like phenomenon.

  10. Strong Lensing Cosmography in the Frontier Fields

    Science.gov (United States)

    Jullo, Eric; Acebron, Ana; Limousin, Marceau; Giocoli, Carlo; Despali, Giulia; Bonamigo, Mario; Bonamigo

    The wealth of strong lensing features observed in the Frontier Fields clusters offers insights on the nature of dark energy. The large number of multiple-images systems with redshifts allows to simultaneously estimate the lens model parameters and the cosmological parameters involved in the distances calculations. In particular for the ΛCDM model, it is possible to estimate the matter density Ω m and the dark energy equations parameters w X . In this talk, I will present recent analyses of systematic errors based on Frontier Fields observed and simulated data.

  11. Dynamical simulations of strongly correlated electron materials

    Science.gov (United States)

    Kress, Joel; Barros, Kipton; Batista, Cristian; Chern, Gia-Wei; Kotliar, Gabriel

    We present a formulation of quantum molecular dynamics that includes electron correlation effects via the Gutzwiller method. Our new scheme enables the study of the dynamical behavior of atoms and molecules with strong electron interactions. The Gutzwiller approach goes beyond the conventional mean-field treatment of the intra-atomic electron repulsion and captures crucial correlation effects such as band narrowing and electron localization. We use Gutzwiller quantum molecular dynamics to investigate the Mott transition in the liquid phase of a single-band metal and uncover intriguing structural and transport properties of the atoms.

  12. Hyperon bulk viscosity in strong magnetic fields

    CERN Document Server

    Sinha, Monika

    2008-01-01

    We study bulk viscosity in neutron star matter including $\\Lambda$ hyperons in the presence of quantizing magnetic fields. Relaxation time and bulk viscosity due to both the non-leptonic weak process involving $\\Lambda$ hyperons and the direct Urca (dUrca) process are calculated here. In the presence of a strong magnetic field, bulk viscosity coefficients are enhanced when protons, electrons and muons are populated in their respective zeroth Landau levels compared with the field free cases. The enhancement of bulk viscosity coefficient is larger for the dUrca case.

  13. Strong Interactions Physics at BaBar

    Energy Technology Data Exchange (ETDEWEB)

    Pioppi, M.

    2005-03-14

    Recent results obtained by BABAR experiment and related to strong interactions physics are presented, with particular attention to the extraction of the first four hadronic-mass moments and the first three lepton-energy moments in semileptonic decays. From a simultaneous fit to the moments, the CKM element |V{sub cb}|, the inclusive B {yields} X{sub c}lv and other heavy quark parameters are derived. The second topic is the ambiguity-free measurement of cos(2{beta}) in B {yields} J/{Psi}K* decays. With approximately 88 million of B{bar B} pairs, negative solutions for cos(2{beta}) are excluded at 89%.

  14. Strong holism, weak holism, and health.

    Science.gov (United States)

    Täljedal, Inge-Bert

    2004-01-01

    The health theories of Nordenfelt and Boorse are compared. Critical attention is focused on Nordenfelt's description of his theory as one of holistic welfare, contrasting with Boorse's analytical and statistical approach. Neither theory is found to give an entirely satisfactory account of 'health' in scientific medicine or common usage. Because Nordenfelt attenuates the ontological significance of organs and organ parts and simplifies the role of statistics, his theory is regarded as weakly holistic. Boorse underrates the importance of non-statistical evaluation. A mediating position, termed 'strong holism' is suggested as a way of integrating normative and statistical elements in a more adequate health concept.

  15. Heteroclinic Bifurcation of Strongly Nonlinear Oscillator

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qi-Chang; WANG Wei; LI Wei-Yi

    2008-01-01

    Analytical prediction of heteroclinic bifurcation of the strongly nonlinear oscillator is presented by using the extended normal form method.We consider the approximate periodic solution of the system subject to the quintic nonlinearity by introducing the undetermined fundamental frequency.For the occurrence of heteroclinicity,the bifurcation criterion is accomplished.It depends on the contact of the limit cycle with the saddle equilibrium.As is illustrated,the explicit application shows that the new results coincide very well with the results of numerical simulation when disturbing parameter is of arbitrary magnitude.PACS: 82.40.Bj,47.20.Ky,02.30.Hq

  16. Strong Turbulence in Low-beta Plasmas

    DEFF Research Database (Denmark)

    Tchen, C. M.; Pécseli, Hans; Larsen, Søren Ejling

    1980-01-01

    An investigation of the spectral structure of turbulence in a plasma confined by a strong homogeneous magnetic field was made by means of a fluid description. The turbulent spectrum is divided into subranges. Mean gradients of velocity and density excite turbulent motions, and govern the production......-3/2 for the potential fluctuations in the production, coupling and inertia subranges, respectively. The coefficient of Bohm diffusion is reproduced, and its role in electrostatic coupling is derived. Comparison is made with measured power laws reported in the literature, from Q-devices, hot...

  17. Light clocks in strong gravitational fields

    CERN Document Server

    Punzi, Raffaele; Wohlfarth, Mattias N R

    2009-01-01

    We argue that the time measured by a light clock operating with photons rather than classical light requires a refinement of the standard clock postulate in general relativity. In the presence of a gravitational field, already the one-loop quantum corrections to classical Maxwell theory affect light propagation and the construction of observers' frames of reference. Carefully taking into account these kinematic effects, a concise geometric expression for the time shown by a light clock is obtained. This result has far-reaching implications for physics in strong gravitational fields.

  18. Strong signatures of right-handed compositeness

    Energy Technology Data Exchange (ETDEWEB)

    Redi, Michele [INFN, Sesto Fiorentino, Firenze (Italy); Sanz, Veronica [York Univ., Toronto, ON (Canada). Dept. of Physics and Astronomy; Sussex Univ., Brighton (United Kingdom). Dept. of Physics and Astronomy; Vries, Maikel de; Weiler, Andreas [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2013-05-15

    Right-handed light quarks could be significantly composite, yet compatible with experimental searches at the LHC and precision tests on Standard Model couplings. In these scenarios, that are motivated by flavor physics, one expects large cross sections for the production of new resonances coupled to light quarks. We study experimental strong signatures of right-handed compositeness at the LHC, and constrain the parameter space of these models with recent results by ATLAS and CMS. We show that the LHC sensitivity could be significantly improved if dedicated searches were performed, in particular in multi-jet signals.

  19. Understanding strongly coupling magnetism from holographic duality

    CERN Document Server

    Cai, Rong-Gen

    2016-01-01

    The unusual magnetic materials are significant in both science and technology. However, because of the strongly correlated effects, it is difficult to understand their novel properties from theoretical aspects. Holographic duality offers a new approach to understanding such systems from gravity side. This paper will give a brief review of our recent works on the applications of holographic duality in understanding unusual magnetic materials. Some quantitative compare between holographic results and experimental data will be shown and some predictions from holographic duality models will be discussed.

  20. Outpatient Provider Concentration and Commercial Colonoscopy Prices

    Directory of Open Access Journals (Sweden)

    Alexis Pozen PhD

    2015-04-01

    Full Text Available The objective was to evaluate the magnitude of various contributors to outpatient commercial colonoscopy prices, including market- and provider-level factors, especially market share. We used adjudicated fee-for-service facility claims from a large commercial insurer for colonoscopies occurring in hospital outpatient department or ambulatory surgery center from October 2005 to December 2012. Claims were matched to provider- and market-level data. Linear fixed effects regressions of negotiated colonoscopy price were run on provider, system, and market characteristics. Markets were defined as counties. There were 178 433 claims from 169 providers (104 systems. The mean system market share was 76% (SD = 0.34 and the mean real (deflated price was US$1363 (SD = 374, ranging from US$169 to US$2748. For every percentage point increase in a system or individual facility’s bed share, relative price increased by 2 to 4 percentage points; this result was stable across a number of specifications. Market population and price were also consistently positively related, though this relation was small in magnitude. No other factor explained price as strongly as market share. Price variation for colonoscopy was driven primarily by market share, of particular concern as the number of mergers increases in wake of the recession and the Affordable Care Act. Whether variation is justified by better quality care requires further research to determine whether quality is subsumed in prices.

  1. Outpatient provider concentration and commercial colonoscopy prices.

    Science.gov (United States)

    Pozen, Alexis

    2015-01-01

    The objective was to evaluate the magnitude of various contributors to outpatient commercial colonoscopy prices, including market- and provider-level factors, especially market share. We used adjudicated fee-for-service facility claims from a large commercial insurer for colonoscopies occurring in hospital outpatient department or ambulatory surgery center from October 2005 to December 2012. Claims were matched to provider- and market-level data. Linear fixed effects regressions of negotiated colonoscopy price were run on provider, system, and market characteristics. Markets were defined as counties. There were 178,433 claims from 169 providers (104 systems). The mean system market share was 76% (SD = 0.34) and the mean real (deflated) price was US$1363 (SD = 374), ranging from US$169 to US$2748. For every percentage point increase in a system or individual facility's bed share, relative price increased by 2 to 4 percentage points; this result was stable across a number of specifications. Market population and price were also consistently positively related, though this relation was small in magnitude. No other factor explained price as strongly as market share. Price variation for colonoscopy was driven primarily by market share, of particular concern as the number of mergers increases in wake of the recession and the Affordable Care Act. Whether variation is justified by better quality care requires further research to determine whether quality is subsumed in prices.

  2. Fractional Transport in Strongly Turbulent Plasmas

    Science.gov (United States)

    Isliker, Heinz; Vlahos, Loukas; Constantinescu, Dana

    2017-07-01

    We analyze statistically the energization of particles in a large scale environment of strong turbulence that is fragmented into a large number of distributed current filaments. The turbulent environment is generated through strongly perturbed, 3D, resistive magnetohydrodynamics simulations, and it emerges naturally from the nonlinear evolution, without a specific reconnection geometry being set up. Based on test-particle simulations, we estimate the transport coefficients in energy space for use in the classical Fokker-Planck (FP) equation, and we show that the latter fails to reproduce the simulation results. The reason is that transport in energy space is highly anomalous (strange), the particles perform Levy flights, and the energy distributions show extended power-law tails. Newly then, we motivate the use and derive the specific form of a fractional transport equation (FTE), we determine its parameters and the order of the fractional derivatives from the simulation data, and we show that the FTE is able to reproduce the high energy part of the simulation data very well. The procedure for determining the FTE parameters also makes clear that it is the analysis of the simulation data that allows us to make the decision whether a classical FP equation or a FTE is appropriate.

  3. Three QSOs acting as strong gravitational lenses

    CERN Document Server

    Courbin, F; Djorgovski, S G; Rerat, F; Tewes, M; Meylan, G; Stern, D; Mahabal, A; Boroson, T; Dheeraj, R; Sluse, D

    2011-01-01

    We report the discovery of three new cases of QSOs acting as strong gravitational lenses on background emission line galaxies: SDSS J0827+5224 (zQSO = 0.293, zs = 0.412), SDSS J0919+2720 (zQSO = 0.209, zs = 0.558), SDSS J1005+4016 (zQSO = 0.230, zs = 0.441). The selection was carried out using a sample of 22,298 SDSS spectra displaying at least four emission lines at a redshift beyond that of the foreground QSO. The lensing nature is confirmed from Keck imaging and spectroscopy, as well as from HST/WFC3 imaging in the F475W and F814W filters. Two of the QSOs have face-on spiral host galaxies and the third is a QSO+galaxy pair. The velocity dispersion of the host galaxies, inferred from simple lens modeling, is between \\sigma_v = 210 and 285 km/s, making these host galaxies comparable in mass with the SLACS sample of early-type strong lenses.

  4. Heat treatment modelling using strongly continuous semigroups.

    Science.gov (United States)

    Malek, Alaeddin; Abbasi, Ghasem

    2015-07-01

    In this paper, mathematical simulation of bioheat transfer phenomenon within the living tissue is studied using the thermal wave model. Three different sources that have therapeutic applications in laser surgery, cornea laser heating and cancer hyperthermia are used. Spatial and transient heating source, on the skin surface and inside biological body, are considered by using step heating, sinusoidal and constant heating. Mathematical simulations describe a non-Fourier process. Exact solution for the corresponding non-Fourier bioheat transfer model that has time lag in its heat flux is proposed using strongly continuous semigroup theory in conjunction with variational methods. The abstract differential equation, infinitesimal generator and corresponding strongly continuous semigroup are proposed. It is proved that related semigroup is a contraction semigroup and is exponentially stable. Mathematical simulations are done for skin burning and thermal therapy in 10 different models and the related solutions are depicted. Unlike numerical solutions, which suffer from uncertain physical results, proposed analytical solutions do not have unwanted numerical oscillations. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Strong eukaryotic IRESs have weak secondary structure.

    Directory of Open Access Journals (Sweden)

    Xuhua Xia

    Full Text Available BACKGROUND: The objective of this work was to investigate the hypothesis that eukaryotic Internal Ribosome Entry Sites (IRES lack secondary structure and to examine the generality of the hypothesis. METHODOLOGY/PRINCIPAL FINDINGS: IRESs of the yeast and the fruit fly are located in the 5'UTR immediately upstream of the initiation codon. The minimum folding energy (MFE of 60 nt RNA segments immediately upstream of the initiation codons was calculated as a proxy of secondary structure stability. MFE of the reverse complements of these 60 nt segments was also calculated. The relationship between MFE and empirically determined IRES activity was investigated to test the hypothesis that strong IRES activity is associated with weak secondary structure. We show that IRES activity in the yeast and the fruit fly correlates strongly with the structural stability, with highest IRES activity found in RNA segments that exhibit the weakest secondary structure. CONCLUSIONS: We found that a subset of eukaryotic IRESs exhibits very low secondary structure in the 5'-UTR sequences immediately upstream of the initiation codon. The consistency in results between the yeast and the fruit fly suggests a possible shared mechanism of cap-independent translation initiation that relies on an unstructured RNA segment.

  6. Strongly intensive measures for multiplicity fluctuations

    Science.gov (United States)

    Begun, V. V.; Konchakovski, V. P.; Gorenstein, M. I.; Bratkovskaya, E. L.

    2013-04-01

    The two recently proposed families of strongly intensive measures of fluctuations and correlations are studied within the hadron-string-dynamics (HSD) transport approach to nucleus-nucleus collisions. We consider the measures ΔKπ and ΣKπ for kaon and pion multiplicities in Au+Au collisions in a wide range of collision energies and centralities. These strongly intensive measures appear to cancel the participant number fluctuations. This allows to enlarge the centrality window in the analysis of event-by-event fluctuations for up to at least 10% of the most central collisions. We also present a comparison of the HSD results with the data of the NA49 and STAR Collaborations. HSD describes ΣKπ reasonably well. However, the HSD results depend monotonously on collision energy and do not reproduce the bump-dip structure of ΔKπ observed from the NA49 data in the region of the center of mass energy of the nucleon pair \\sqrt{s_{NN}}= 8{--}12 GeV. This observation deserves further study. The origin of this ‘structure’ is not connected with simple geometrical or limited acceptance effects, as these effects are taken into account in HSD simulations.

  7. Strong white photoluminescence from annealed zeolites

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Zhenhua, E-mail: baizh46@gmail.com [School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637457 (Singapore); Fujii, Minoru; Imakita, Kenji; Hayashi, Shinji [Department of Electrical and Electronic Engineering, Graduate School of Engineering, Kobe University, Rokkodai, Nada, Kobe 657-8501 (Japan)

    2014-01-15

    The optical properties of zeolites annealed at various temperatures are investigated for the first time. The annealed zeolites exhibit strong white photoluminescence (PL) under ultraviolet light excitation. With increasing annealing temperature, the emission intensity of annealed zeolites first increases and then decreases. At the same time, the PL peak red-shifts from 495 nm to 530 nm, and then returns to 500 nm. The strongest emission appears when the annealing temperature is 500 °C. The quantum yield of the sample is measured to be ∼10%. The PL lifetime monotonously increases from 223 μs to 251 μs with increasing annealing temperature. The origin of white PL is ascribed to oxygen vacancies formed during the annealing process. -- Highlights: • The optical properties of zeolites annealed at various temperatures are investigated. • The annealed zeolites exhibit strong white photoluminescence. • The maximum PL enhancement reaches as large as 62 times. • The lifetime shows little dependence on annealing temperature. • The origin of white emission is ascribed to the oxygen vacancies.

  8. Are Anesthesia Providers Ready for Hypnosis? Anesthesia Providers' Attitudes Toward Hypnotherapy.

    Science.gov (United States)

    Stone, Alexander B; Sheinberg, Rosanne; Bertram, Amanda; Seymour, Anastasia Rowland

    2016-04-01

    This study sought to measure current attitudes toward hypnosis among anesthesia providers using an in-person survey distributed at a single grand rounds at a single academic teaching hospital. One hundred twenty-six anesthesia providers (anesthesiologists and nurse anesthetists) were included in this study. A 10-question Institutional Review Board (IRB)-approved questionnaire was developed. One hundred twenty-six (73% of providers at the meeting) anesthesia providers completed the survey. Of the respondents, 54 (43%) were anesthesiologists, 42 (33%) were trainees (interns/residents/fellows) in anesthesia, and 30 (24%) were nurse anesthetists. Over 70% of providers, at each level of training, rated their knowledge of hypnosis as either below average or having no knowledge. Fifty-two (42%) providers agreed or strongly agreed that hypnotherapy has a place in the clinical practice of anesthesia, while 103 (83%) believed that positive suggestion has a place in the clinical practice of anesthesia (p hypnosis were that it is too time consuming (41%) and requires special training (34%). Only three respondents (2%) believed that there were no reasons for using hypnosis in their practice. These data suggest that there is a self-reported lack of knowledge about hypnosis among anesthesia providers, although many anesthesia providers are open to the use of hypnosis in their clinical practice. Anesthesia providers are more likely to support the use of positive suggestion in their practice than hypnosis. Practical concerns should be addressed if hypnosis and therapeutic verbal techniques are to gain more widespread use.

  9. Strong electronic correlation effects in coherent multidimensional nonlinear optical spectroscopy.

    Science.gov (United States)

    Karadimitriou, M E; Kavousanaki, E G; Dani, K M; Fromer, N A; Perakis, I E

    2011-05-12

    We discuss a many-body theory of the coherent ultrafast nonlinear optical response of systems with a strongly correlated electronic ground state that responds unadiabatically to photoexcitation. We introduce a truncation of quantum kinetic density matrix equations of motion that does not rely on an expansion in terms of the interactions and thus applies to strongly correlated systems. For this we expand in terms of the optical field, separate out contributions to the time-evolved many-body state due to correlated and uncorrelated multiple optical transitions, and use "Hubbard operator" density matrices to describe the exact dynamics of the individual contributions within a subspace of strongly coupled states, including "pure dephasing". Our purpose is to develop a quantum mechanical tool capable of exploring how, by coherently photoexciting selected modes, one can trigger nonlinear dynamics of strongly coupled degrees of freedom. Such dynamics could lead to photoinduced phase transitions. We apply our theory to the nonlinear response of a two-dimensional electron gas (2DEG) in a magnetic field. We coherently photoexcite the two lowest Landau level (LL) excitations using three time-delayed optical pulses. We identify some striking temporal and spectral features due to dynamical coupling of the two LLs facilitated by inter-Landau-level magnetoplasmon and magnetoroton excitations and compare to three-pulse four-wave-mixing (FWM) experiments. We show that these features depend sensitively on the dynamics of four-particle correlations between an electron-hole pair and a magnetoplasmon/magnetoroton, reminiscent of exciton-exciton correlations in undoped semiconductors. Our results shed light into unexplored coherent dynamics and relaxation of the quantum Hall system (QHS) and can provide new insight into non-equilibrium co-operative phenomena in strongly correlated systems.

  10. Energy levels of light atoms in strong magnetic fields

    CERN Document Server

    Thirumalai, Anand

    2014-01-01

    In this review article we provide an overview of the field of atomic structure of light atoms in strong magnetic fields. There is a very rich history of this field which dates back to the very birth of quantum mechanics. At various points in the past significant discoveries in science and technology have repeatedly served to rejuvenate interest in atomic structure in strong fields, broadly speaking, resulting in three eras in the development of this field; the historical, the classical and the modern eras. The motivations for studying atomic structure have also changed significantly as time progressed. The review presents a chronological summary of the major advances that occurred during these eras and discusses new insights and impetus gained. The review is concluded with a description of the latest findings and the future prospects for one of the most remarkably cutting-edge fields of research in science today.

  11. Spontaneous avalanche ionization of a strongly blockaded Rydberg gas

    CERN Document Server

    Robert-de-Saint-Vincent, M; Schempp, H; Günter, G; Whitlock, S; Weidemüller, M

    2012-01-01

    We report the sudden and spontaneous evolution of an initially correlated gas of repulsively interacting Rydberg atoms to an ultracold plasma. Under continuous laser coupling we create a Rydberg ensemble in the strong blockade regime, which at longer times undergoes an ionization avalanche. By combining optical imaging and ion detection, we access the full information on the dynamical evolution of the system, including the rapid increase in the number of ions and a sudden depletion of the Rydberg and ground state densities. Rydberg-Rydberg interactions are observed to strongly affect the dynamics of plasma formation. Using a coupled rate-equation model to describe our data, we extract the average energy of electrons trapped in the plasma, and an effective cross-section for ionizing collisions between Rydberg atoms and atoms in low-lying states. Our results suggest that the initial correlations of the Rydberg ensemble should persist through the avalanche. This would provide the means to overcome disorder-induc...

  12. Towards generic resolution of strong singularities in loop quantum cosmology

    Science.gov (United States)

    Singh, Parampreet

    2010-10-01

    Singularities are the boundaries of classical spacetime in General Relativity. It has been always hoped that quantum gravitational effects may resolve these singularities. In recent years, progress in loop quantum cosmology has provided insights on the resolution of big bang, big crunch and other spacelike singularities. In this talk we will give an update on the recent status of the generic resolution of strong spacelike singularities in loop quantum cosmology. We will show that for flat and curved Roberston-Walker backgrounds and also for Bianchi-I models, loop quantum gravity effects resolve all strong curvature singularities. However, weak curvature singularities, that is those beyond which geodesics can be continued, may not be resolved.

  13. Weak and strong coupling equilibration in nonabelian gauge theories

    CERN Document Server

    Keegan, Liam; Romatschke, Paul; van der Schee, Wilke; Zhu, Yan

    2016-01-01

    We present a direct comparison studying equilibration through kinetic theory at weak coupling and through holography at strong coupling in the same set-up. The set-up starts with a homogeneous thermal state, which then smoothly transitions through an out-of-equilibrium phase to an expanding system undergoing boost-invariant flow. This first apples-to-apples comparison of equilibration provides a benchmark for similar equilibration processes in heavy-ion collisions, where the equilibration mechanism is still under debate. We find that results at weak and strong coupling can be smoothly connected by simple, empirical power-laws for the viscosity, equilibration time and entropy production of the system.

  14. “Hard probes” of strongly-interacting atomic gases

    Energy Technology Data Exchange (ETDEWEB)

    Nishida, Yusuke [Los Alamos National Laboratory

    2012-06-18

    We investigate properties of an energetic atom propagating through strongly interacting atomic gases. The operator product expansion is used to systematically compute a quasiparticle energy and its scattering rate both in a spin-1/2 Fermi gas and in a spinless Bose gas. Reasonable agreement with recent quantum Monte Carlo simulations even at a relatively small momentum k/kF > 1.5 indicates that our large-momentum expansions are valid in a wide range of momentum. We also study a differential scattering rate when a probe atom is shot into atomic gases. Because the number density and current density of the target atomic gas contribute to the forward scattering only, its contact density (measure of short-range pair correlation) gives the leading contribution to the backward scattering. Therefore, such an experiment can be used to measure the contact density and thus provides a new local probe of strongly interacting atomic gases.

  15. Strong deflection gravitational lensing by a modified Hayward black hole

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Shan-Shan; Xie, Yi [Nanjing University, School of Astronomy and Space Science, Nanjing (China); Nanjing University, Ministry of Education, Key Laboratory of Modern Astronomy and Astrophysics, Nanjing (China)

    2017-05-15

    A modified Hayward black hole is a nonsingular black hole. It is proposed that it would form when the pressure generated by quantum gravity can stop matter's collapse as the matter reaches the Planck density. Strong deflection gravitational lensing occurring nearby its event horizon might provide some clues of these quantum effects in its central core. We investigate observables of the strong deflection lensing, including angular separations, brightness differences and time delays between its relativistic images, and we estimate their values for the supermassive black hole in the Galactic center. We find that it is possible to distinguish the modified Hayward black hole from a Schwarzschild one, but it demands a very high resolution, beyond current stage. (orig.)

  16. Strong Analog Classical Simulation of Coherent Quantum Dynamics

    Science.gov (United States)

    Wang, Dong-Sheng

    2017-02-01

    A strong analog classical simulation of general quantum evolution is proposed, which serves as a novel scheme in quantum computation and simulation. The scheme employs the approach of geometric quantum mechanics and quantum informational technique of quantum tomography, which applies broadly to cases of mixed states, nonunitary evolution, and infinite dimensional systems. The simulation provides an intriguing classical picture to probe quantum phenomena, namely, a coherent quantum dynamics can be viewed as a globally constrained classical Hamiltonian dynamics of a collection of coupled particles or strings. Efficiency analysis reveals a fundamental difference between the locality in real space and locality in Hilbert space, the latter enables efficient strong analog classical simulations. Examples are also studied to highlight the differences and gaps among various simulation methods. Funding support from NSERC of Canada and a research fellowship at Department of Physics and Astronomy, University of British Columbia are acknowledged

  17. Creation and survival of autoionizing states in strong laser fields

    Science.gov (United States)

    Fechner, Lutz; Camus, Nicolas; Krupp, Andreas; Ullrich, Joachim; Pfeifer, Thomas; Moshammer, Robert

    2015-11-01

    Very sharp, low-energy structures observed in photoelectron spectra reveal the population of autoionizing states in krypton and argon in strong laser fields over a large range of different wavelengths. The energies of the electrons, emitted by autoionization in a field-free environment, provide direct information about the spectrum of states involved. Despite their ability to resist ionization by the populating laser pulse, we demonstrate the possibility to promote the excited electrons into the continuum by subsequent absorption of a single photon. Thus, applying a classical pump-probe scheme, we are able to manipulate the autoionization contribution on a picosecond time scale. Different scenarios for the creation of autoionizing states in strong laser fields are discussed.

  18. Evolutionary dynamics with fluctuating population sizes and strong mutualism

    Science.gov (United States)

    Chotibut, Thiparat; Nelson, David R.

    2015-08-01

    Game theory ideas provide a useful framework for studying evolutionary dynamics in a well-mixed environment. This approach, however, typically enforces a strictly fixed overall population size, deemphasizing natural growth processes. We study a competitive Lotka-Volterra model, with number fluctuations, that accounts for natural population growth and encompasses interaction scenarios typical of evolutionary games. We show that, in an appropriate limit, the model describes standard evolutionary games with both genetic drift and overall population size fluctuations. However, there are also regimes where a varying population size can strongly influence the evolutionary dynamics. We focus on the strong mutualism scenario and demonstrate that standard evolutionary game theory fails to describe our simulation results. We then analytically and numerically determine fixation probabilities as well as mean fixation times using matched asymptotic expansions, taking into account the population size degree of freedom. These results elucidate the interplay between population dynamics and evolutionary dynamics in well-mixed systems.

  19. LDA+DMFT Approach to Magnetocrystalline Anisotropy of Strong Magnets

    Directory of Open Access Journals (Sweden)

    Jian-Xin Zhu

    2014-05-01

    Full Text Available The new challenges posed by the need of finding strong rare-earth-free magnets demand methods that can predict magnetization and magnetocrystalline anisotropy energy (MAE. We argue that correlated electron effects, which are normally underestimated in band-structure calculations, play a crucial role in the development of the orbital component of the magnetic moments. Because magnetic anisotropy arises from this orbital component, the ability to include correlation effects has profound consequences on our predictive power of the MAE of strong magnets. Here, we show that incorporating the local effects of electronic correlations with dynamical mean-field theory provides reliable estimates of the orbital moment, the mass enhancement, and the MAE of YCo_{5}.

  20. Horizontal mergers and weak and strong competition commissions

    Directory of Open Access Journals (Sweden)

    Ristić Bojan

    2014-01-01

    Full Text Available In this paper we analyse the horizontal merger of companies in an already concentrated industry. The participants in mergers are obliged to submit notification to the Competition Commission but they also have the option of rejecting the merger. At the time of the notification submission the participants do not know whether the Commission is strong or weak, and they can complain to the Court if the Commission prohibits the merger. We model the strategic interaction between Participants and Commission in a dynamic game of incomplete information and determine weak perfect Bayesian equilibria. The main finding of our paper is that Participants will base their decision to submit notification on their belief in a weak Commission decision and will almost completely ignore the possibility of a strong Commission decision. We also provide a detailed examination of one case from Serbian regulatory practice, which coincides with the results of our game theoretical model.

  1. Radial sensitivity of kaonic atoms and strongly bound K¯ states

    Science.gov (United States)

    Barnea, N.; Friedman, E.

    2007-02-01

    The strength of the low-energy K--nucleus real potential has recently received renewed attention in view of experimental evidence for the possible existence of strongly bound K- states. Previous fits to kaonic atom data led to either “shallow” or “deep” potentials, where only the former are in agreement with chiral approaches but only the latter can produce strongly bound states. Here we explore the uncertainties of the K--nucleus optical potentials, obtained from fits to kaonic atom data, using the functional derivatives of the best-fit χ2 values with respect to the potential. We find that only the deep type of potential provides information that is applicable to the K- interaction in the nuclear interior.

  2. Strong coupling theory of heavy fermion criticality II

    Science.gov (United States)

    Wölfle, Peter; Schmalian, Jörg; Abrahams, Elihu

    2017-04-01

    We present a theory of the scaling behavior of the thermodynamic, transport and dynamical properties of a three-dimensional metal governed by d-dimensional fluctuations at a quantum critical point, where the electron quasiparticle effective mass diverges. We determine how the critical bosonic order parameter fluctuations are affected by the effective mass divergence. The coupled system of fermions and bosons is found to be governed by two stable fixed points: the conventional weak-coupling fixed point and a new strong-coupling fixed point, provided the boson–boson interaction is irrelevant. The latter fixed point supports hyperscaling, characterized by fractional exponents. The theory is applied to the antiferromagnetic critical point in certain heavy fermion compounds, in which the strong-coupling regime is reached.

  3. Knudsen Gas Provides Nanobubble Stability

    NARCIS (Netherlands)

    Seddon, James Richard Thorley; Zandvliet, Henricus J.W.; Lohse, Detlef

    2011-01-01

    We provide a model for the remarkable stability of surface nanobubbles to bulk dissolution. The key to the solution is that the gas in a nanobubble is of Knudsen type. This leads to the generation of a bulk liquid flow which effectively forces the diffusive gas to remain local. Our model predicts

  4. Twitter for travel medicine providers.

    Science.gov (United States)

    Mills, Deborah J; Kohl, Sarah E

    2016-03-01

    Travel medicine practitioners, perhaps more so than medical practitioners working in other areas of medicine, require a constant flow of information to stay up-to-date, and provide best practice information and care to their patients. Many travel medicine providers are unaware of the popularity and potential of the Twitter platform. Twitter use among our travellers, as well as by physicians and health providers, is growing exponentially. There is a rapidly expanding body of published literature on this information tool. This review provides a brief overview of the ways Twitter is being used by health practitioners, the advantages that are peculiar to Twitter as a platform of social media, and how the interested practitioner can get started. Some key points about the dark side of Twitter are highlighted, as well as the potential benefits of using Twitter as a way to disseminate accurate medical information to the public. This article will help readers develop an increased understanding of Twitter as a tool for extracting useful facts and insights from the ever increasing volume of health information. © International Society of Travel Medicine, 2016. All rights reserved. Published by Oxford University Press. For permissions, please e-mail: journals.permissions@oup.com.

  5. Strong Ground Motion Database System for the Mexican Seismic Network

    Science.gov (United States)

    Perez-Yanez, C.; Ramirez-Guzman, L.; Ruiz, A. L.; Delgado, R.; Macías, M. A.; Sandoval, H.; Alcántara, L.; Quiroz, A.

    2014-12-01

    A web-based system for strong Mexican ground motion records dissemination and archival is presented. More than 50 years of continuous strong ground motion instrumentation and monitoring in Mexico have provided a fundamental resource -several thousands of accelerograms- for better understanding earthquakes and their effects in the region. Lead by the Institute of Engineering (IE) of the National Autonomous University of Mexico (UNAM), the engineering strong ground motion monitoring program at IE relies on a continuously growing network, that at present includes more than 100 free-field stations and provides coverage to the seismic zones in the country. Among the stations, approximately 25% send the observed acceleration to a processing center in Mexico City in real-time, and the rest require manual access, remote or in situ, for later processing and cataloguing. As part of a collaboration agreement between UNAM and the National Center for Disaster Prevention, regarding the construction and operation of a unified seismic network, a web system was developed to allow access to UNAM's engineering strong motion archive and host data from other institutions. The system allows data searches under a relational database schema, following a general structure relying on four databases containing the: 1) free-field stations, 2) epicentral location associated with the strong motion records available, 3) strong motion catalogue, and 4) acceleration files -the core of the system. In order to locate and easily access one or several records of the data bank, the web system presents a variety of parameters that can be involved in a query (seismic event, region boundary, station name or ID, radial distance to source or peak acceleration). This homogeneous platform has been designed to facilitate dissemination and processing of the information worldwide. Each file, in a standard format, contains information regarding the recording instrument, the station, the corresponding earthquake

  6. Chiral symmetry restoration and strong CP violation in a strong magnetic background

    CERN Document Server

    Fraga, Eduardo S

    2009-01-01

    Motivated by the phenomenological scenario of the chiral magnetic effect that can be possibly found in high-energy heavy ion collisions, we study the role of very intense magnetic fields and strong CP violation in the phase structure of strong interactions and, more specifically, their influence on the nature of the chiral transition. Direct implications for the dynamics of phase conversion and its time scales are briefly discussed. Our results can also be relevant in the case of the early universe.

  7. Chiral symmetry restoration and strong CP violation in a strong magnetic background

    OpenAIRE

    Fraga, Eduardo S.; Mizher, Ana Júlia

    2009-01-01

    Motivated by the phenomenological scenario of the chiral magnetic effect that can be possibly found in high-energy heavy ion collisions, we study the role of very intense magnetic fields and strong CP violation in the phase structure of strong interactions and, more specifically, their influence on the nature of the chiral transition. Direct implications for the dynamics of phase conversion and its time scales are briefly discussed. Our results can also be relevant in the case of the early un...

  8. Strong-Strong Beam-Beam Simulation of Bunch Length Splitting at the LHC

    CERN Document Server

    Qiang, J; Pieloni, Tatiana; Ohmi, Kazuhito

    2015-01-01

    Longitudinal bunch length splitting was observed for some LHC beams. In this paper, we will report on the study of the observation using strong-strong beam-beam simulations. We explore a variety of factors including initial momentum deviation, collision crossing angle, synchrotron tune, chromaticity, working points and bunch intensity that contribute to the beam particle loss and the bunch length splitting, and try to understand the underlying mechanism of the observed phenomena.

  9. Strong correlations in gravity and biophysics

    Science.gov (United States)

    Krotov, Dmitry

    The unifying theme of this dissertation is the use of correlations. In the first part (chapter 2), we investigate correlations in quantum field theories in de Sitter space. In the second part (chapters 3,4,5), we use correlations to investigate a theoretical proposal that real (observed in nature) transcriptional networks of biological organisms are operating at a critical point in their phase diagram. In chapter 2 we study the infrared dependence of correlators in various external backgrounds. Using the Schwinger-Keldysh formalism we calculate loop corrections to the correlators in the case of the Poincare patch and the complete de Sitter space. In the case of the Poincare patch, the loop correction modifies the behavior of the correlator at large distances. In the case of the complete de Sitter space, the loop correction has a strong dependence on the infrared cutoff in the past. It grows linearly with time, suggesting that at some point the correlations become strong and break the symmetry of the classical background. In chapter 3 we derive the signatures of critical behavior in a model organism, the embryo of Drosophila melanogaster. They are: strong correlations in the fluctuations of different genes, a slowing of dynamics, long range correlations in space, and departures from a Gaussian distribution of these fluctuations. We argue that these signatures are observed experimentally. In chapter 4 we construct an effective theory for the zero mode in this system. This theory is different from the standard Landau-Ginsburg description. It contains gauge fields (the result of the broken translational symmetry inside the cell), which produce observable contributions to the two-point function of the order parameter. We show that the behavior of the two-point function for the network of N genes is described by the action of a relativistic particle moving on the surface of the N - 1 dimensional sphere. We derive a theoretical bound on the decay of the correlations and

  10. Framing the future: sme logistics service providers and scenario planning

    NARCIS (Netherlands)

    Glöckner, Hans-Heinrich; Pieters, Reinder; Weijers, Stef; Woodburn, Allan

    2013-01-01

    In recent years, the transport industry has encountered numerous challenges. It experienced strong growth, but also many uncertainties. In many cases, logistics service providers were forced to change their strategy. So, the question for logistics service providers arises “how to deal best with unce

  11. Dyson-Schwinger Equation Density, Temperature and Continuum Strong QCD

    CERN Document Server

    Roberts, C D

    2000-01-01

    Continuum strong QCD is the application of models and continuum quantum field theory to the study of phenomena in hadronic physics, which includes; e.g., the spectrum of QCD bound states and their interactions; and the transition to, and properties of, a quark gluon plasma. We provide a contemporary perspective, couched primarily in terms of the Dyson-Schwinger equations but also making comparisons with other approaches and models. Our discourse provides a practitioners' guide to features of the Dyson-Schwinger equations [such as confinement and dynamical chiral symmetry breaking] and canvasses phenomenological applications to light meson and baryon properties in cold, sparse QCD. These provide the foundation for an extension to hot, dense QCD, which is probed via the introduction of the intensive thermodynamic variables: chemical potential and temperature. We describe order parameters whose evolution signals deconfinement and chiral symmetry restoration, and chronicle their use in demarcating the quark gluon...

  12. Service Provider DevOps

    OpenAIRE

    John, Wolfgang; Marchetto, Guido; Németh, Felicián; Sköldström, Pontus; Steinert, Rebecca; Meirosu, Catalin; Papafili, Ioanna; Pentikousis, Kostas

    2017-01-01

    Although there is consensus that software defined networking and network functions virtualization overhaul service provisioning and deployment, the community still lacks a definite answer on how carrier-grade operations praxis needs to evolve. This article presents what lies beyond the first evolutionary steps in network management, identifies the challenges in service verification, observability, and troubleshooting, and explains how to address them using our Service Provider DevOps (SP-DevO...

  13. Community dental clinics: providers' perspectives.

    Science.gov (United States)

    Wallace, Bruce B; MacEntee, Michael I; Harrison, Rosamund; Hole, Rachelle; Mitton, Craig

    2013-06-01

    Not-for-profit community dental clinics attempt to address the inequities of oral health care for disadvantaged communities, but there is little information about how they operate. The objective of this article is to explain from the perspective of senior staff how five community dental clinics in British Columbia, Canada, provide services. The mixed-methods case study included the five not-for-profit dental clinics with full-time staff who provided a wide range of dental services. We conducted open-ended interviews to saturation with eight senior administrative staff selected purposefully because of their comprehensive knowledge of the development and operation of the clinics and supplemented their information with a year's aggregated data on patients, treatments, and operating costs. The interview participants described the benefits of integrating dentistry with other health and social services usually within community health centres, although they doubted the sustainability of the clinics without reliable financial support from public funds. Aggregated data showed that 75% of the patients had either publically funded or no coverage for dental services, while the others had employer-sponsored dental insurance. Financial subsidies from regional health authorities allowed two of the clinics to treat only patients who are economically vulnerable and provide all services at reduced costs. Clinics without government subsidies used the fees paid by some patients to subsidize treatment for others who could not afford treatment. Not-for-profit dental clinics provide dental services beyond pain relief for underserved communities. Dental services are integrated with other health and community services and located in accessible locations. However, all of the participants expressed concerns about the sustainability of the clinics without reliable public revenues. © 2012 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Strongly magnetized rotating dipole in general relativity

    CERN Document Server

    Petri, J

    2016-01-01

    Electromagnetic waves arise in many area of physics. Solutions are difficult to find in the general case. In this paper, we numerically integrate Maxwell equations in a 3D spherical polar coordinate system. Straightforward finite difference methods would lead to a coordinate singularity along the polar axis. Spectral methods are better suited to deal with such artificial singularities related to the choice of a coordinate system. When the radiating object is rotating like for instance a star, special classes of solutions to Maxwell equations are worthwhile to study such as quasi-stationary regimes. Moreover, in high-energy astrophysics, strong gravitational and magnetic fields are present especially around rotating neutron stars. In order to study such systems, we designed an algorithm to solve the time-dependent Maxwell equations in spherical polar coordinates including general relativity as well as quantum electrodynamical corrections to leading order. As a diagnostic, we compute the spindown luminosity exp...

  15. Observable properties of strong gravitational lenses

    Science.gov (United States)

    Tessore, Nicolas

    2017-01-01

    It is shown which properties of a strong gravitational lens can in principle be recovered from observations of multiple extended images when no assumptions are made about the deflector or sources. The mapping between individual multiple images is identified as the carrier of information about the gravitational lens and it is shown how this information can be extracted from a hypothetical observation. The derivatives of the image map contain information about convergence ratios and reduced shears over the regions of the multiple images. For two observed images, it is not possible to reconstruct the convergence ratio and shear at the same time. For three observed images, it is possible to recover the convergence ratios and reduced shears identically. For four or more observed images, the system of constraints is overdetermined, but the same quantities can theoretically be recovered.

  16. The last word in strong correlations

    Energy Technology Data Exchange (ETDEWEB)

    Shankar, R. [Sloane Physics Laboratory, Yale University New Haven, CT 06520 (United States)

    2011-08-26

    In the Fractional Quantum Hall Effect (FQHE), in the noninteracting limit, only a fraction {nu} of the Lowest Landau Level (LLL) is occupied, producing a huge degeneracy. Interactions lift this degeneracy and mix in higher LL's. In the limit in which we ignore all but the LLL (i.e., let the inverse electron mass 1/m {yields} {infinity}), the kinetic energy is an irrelevant constant and the ratio of potential to kinetic energy is essentially infinite, making this the most strongly correlated problem imaginable. I give a telegraphic review of the Hamiltonian Theory of the FQHE developed with Ganpathy Murthy that deals with this problem with some success. A nodding acquaintance with FQHE physics is presumed. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. Strong polarization mode coupling in microresonators

    CERN Document Server

    Ramelow, Sven; Clemmen, Stéphane; Levy, Jacob S; Johnson, Adrea R; Okawachi, Yoshitomo; Lamont, Michael R E; Lipson, Michal; Gaeta, Alexander L

    2014-01-01

    We observe strong modal coupling between the TE00 and TM00 modes in Si3N4 ring resonators revealed by avoided crossings of the corresponding resonances. Such couplings result in significant shifts of the resonance frequencies over a wide range around the crossing points. This leads to an effective dispersion that is one order of magnitude larger than the intrinsic dispersion and creates broad windows of anomalous dispersion. We also observe the changes to frequency comb spectra generated in Si3N4 microresonators due polarization mode and higher-order mode crossings and suggest approaches to avoid these effects. Alternatively, such polarization mode-crossings can be used as a novel tool for dispersion engineering in microresonators.

  18. The new <Strong Italian Earthquakes>>

    Directory of Open Access Journals (Sweden)

    G. Valensise

    1995-06-01

    Full Text Available We describe a new catalogue of strong ltalian earthquakes that the Istituto Nazionale di Geofisica in collaboration with SGA, has recently made available to the international scientific community and to the general public. The new catalogue differs from previous efforts in that for each event the usual seismic parameters are complemented by a list of intensity rated localities, a complete list of relevant references, a series of synoptic comments describing different aspects of the earthquake phenomenology. and in most cases even the text of the original written sources. The printed part of the catalogue has been published as a special monograph which contains also a computer version of the full database in the form of a CD-ROM. The software package includes a computer program for retrieving, selecting and displaying the catalogue data.

  19. Strong solutions of semilinear matched microstructure models

    CERN Document Server

    Escher, Joachim

    2011-01-01

    The subject of this article is a matched microstructure model for Newtonian fluid flows in fractured porous media. This is a homogenized model which takes the form of two coupled parabolic differential equations with boundary conditions in a given (two-scale) domain in Euclidean space. The main objective is to establish the local well-posedness in the strong sense of the flow. Two main settings are investigated: semi-linear systems with linear boundary conditions and semi-linear systems with nonlinear boundary conditions. With the help of analytic semigoups we establish local well-posedness and investigate the long-time behaviour of the solutions in the first case: we establish global existence and show that solutions converge to zero at an exponential rate.

  20. Model Reduction of Strong-Weak Neurons

    Directory of Open Access Journals (Sweden)

    Steven James Cox

    2014-12-01

    Full Text Available We consider neurons with large dendritic trees that are weakly excitable in the sense that back propagating action potentials are severly attenuated as they travelfrom the small, strongly excitable, spike initiation zone. In previous workwe have shown that the computational size of weakly excitable cell modelsmay be reduced by two or more orders of magnitude, and that the size of stronglyexcitable models may be reduced by at least one order of magnitude,without sacrificing thespatio-temporal nature of its inputs (in the sense we reproduce the cell's precise mapping of inputs to outputs. We combine the best of these twostrategies via a predictor--corrector decomposition scheme andachieve a drastically reduced highly accurate model of a caricature of the neuron responsible for collision detection in the locust.

  1. Machine Learning Phases of Strongly Correlated Fermions

    Directory of Open Access Journals (Sweden)

    Kelvin Ch’ng

    2017-08-01

    Full Text Available Machine learning offers an unprecedented perspective for the problem of classifying phases in condensed matter physics. We employ neural-network machine learning techniques to distinguish finite-temperature phases of the strongly correlated fermions on cubic lattices. We show that a three-dimensional convolutional network trained on auxiliary field configurations produced by quantum Monte Carlo simulations of the Hubbard model can correctly predict the magnetic phase diagram of the model at the average density of one (half filling. We then use the network, trained at half filling, to explore the trend in the transition temperature as the system is doped away from half filling. This transfer learning approach predicts that the instability to the magnetic phase extends to at least 5% doping in this region. Our results pave the way for other machine learning applications in correlated quantum many-body systems.

  2. Nonlinear parallel momentum transport in strong turbulence

    CERN Document Server

    Wang, Lu; Diamond, P H

    2015-01-01

    Most existing theoretical studies of momentum transport focus on calculating the Reynolds stress based on quasilinear theory, without considering the \\emph{nonlinear} momentum flux-$$. However, a recent experiment on TORPEX found that the nonlinear toroidal momentum flux induced by blobs makes a significant contribution as compared to the Reynolds stress [Labit et al., Phys. Plasmas {\\bf 18}, 032308 (2011)]. In this work, the nonlinear parallel momentum flux in strong turbulence is calculated by using three dimensional Hasegawa-Mima equation. It is shown that nonlinear diffusivity is smaller than quasilinear diffusivity from Reynolds stress. However, the leading order nonlinear residual stress can be comparable to the quasilinear residual stress, and so could be important to intrinsic rotation in tokamak edge plasmas. A key difference from the quasilinear residual stress is that parallel fluctuation spectrum asymmetry is not required for nonlinear residual stress.

  3. Observable properties of strong gravitational lenses

    CERN Document Server

    Tessore, Nicolas

    2016-01-01

    It is shown which properties of a strong gravitational lens can in principle be recovered from observations of multiple extended images when no assumptions are made about the deflector or sources. The mapping between individual multiple images is identified as the carrier of information about the gravitational lens and it is shown how this information can be extracted from a hypothetical observation. The derivatives of the image map contain information about convergence ratios and reduced shears over the regions of the multiple images. For two observed images, it is not possible to reconstruct the convergence ratio and shear at the same time. For three observed images, it is possible to recover the convergence ratios and reduced shears identically. For four or more observed images, the system of constraints is overdetermined, but the same quantities can theoretically be recovered.

  4. Circuit electromechanics with single photon strong coupling

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Zheng-Yuan, E-mail: zyxue@scnu.edu.cn; Yang, Li-Na [Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China); Zhou, Jian, E-mail: jianzhou8627@163.com [Department of Electronic Communication Engineering, Anhui Xinhua University, Hefei 230088 (China); Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, and School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China)

    2015-07-13

    In circuit electromechanics, the coupling strength is usually very small. Here, replacing the capacitor in circuit electromechanics by a superconducting flux qubit, we show that the coupling among the qubit and the two resonators can induce effective electromechanical coupling which can attain the strong coupling regime at the single photon level with feasible experimental parameters. We use dispersive couplings among two resonators and the qubit while the qubit is also driven by an external classical field. These couplings form a three-wave mixing configuration among the three elements where the qubit degree of freedom can be adiabatically eliminated, and thus results in the enhanced coupling between the two resonators. Therefore, our work constitutes the first step towards studying quantum nonlinear effect in circuit electromechanics.

  5. Is It Possible to Predict Strong Earthquakes?

    CERN Document Server

    Polyakov, Yuriy S; Solovyeva, Anna B; Timashev, Serge F

    2015-01-01

    The possibility of earthquake prediction is one of the key open questions in modern geophysics. We propose an approach based on the analysis of common short-term candidate precursors (2 weeks to 3 months prior to strong earthquake) with the subsequent processing of brain activity signals generated in specific types of rats (kept in laboratory settings) who reportedly sense an impending earthquake few days prior to the event. We illustrate the identification of short-term precursors using the groundwater sodium-ion concentration data in the time frame from 2010 to 2014 (a major earthquake occurred on February 28, 2013), recorded at two different sites in the south-eastern part of the Kamchatka peninsula, Russia. The candidate precursors are observed as synchronized peaks in the nonstationarity factors, introduced within the flicker-noise spectroscopy framework for signal processing, for the high-frequency component of both time series. These peaks correspond to the local reorganizations of the underlying geoph...

  6. Machine Learning Phases of Strongly Correlated Fermions

    Science.gov (United States)

    Ch'ng, Kelvin; Carrasquilla, Juan; Melko, Roger G.; Khatami, Ehsan

    2017-07-01

    Machine learning offers an unprecedented perspective for the problem of classifying phases in condensed matter physics. We employ neural-network machine learning techniques to distinguish finite-temperature phases of the strongly correlated fermions on cubic lattices. We show that a three-dimensional convolutional network trained on auxiliary field configurations produced by quantum Monte Carlo simulations of the Hubbard model can correctly predict the magnetic phase diagram of the model at the average density of one (half filling). We then use the network, trained at half filling, to explore the trend in the transition temperature as the system is doped away from half filling. This transfer learning approach predicts that the instability to the magnetic phase extends to at least 5% doping in this region. Our results pave the way for other machine learning applications in correlated quantum many-body systems.

  7. Towards Integrated Marmara Strong Motion Network

    Science.gov (United States)

    Durukal, E.; Erdik, M.; Safak, E.; Ansal, A.; Ozel, O.; Alcik, H.; Mert, A.; Kafadar, N.; Korkmaz, A.; Kurtulus, A.

    2009-04-01

    Istanbul has a 65% chance of having a magnitude 7 or above earthquake within the next 30 years. As part of the preparations for the future earthquake, strong motion networks have been installed in and around Istanbul. The Marmara Strong Motion Network, operated by the Department of Earthquake Engineering of Kandilli Observatory and Earthquake Research Institute, encompasses permanent systems outlined below. It is envisaged that the networks will be run by a single entity responsible for technical management and maintanence, as well as for data management, archiving and dissemination through dedicated web-based interfaces. • Istanbul Earthquake Rapid Response and Early Warning System - IERREWS (one hundred 18-bit accelerometers for rapid response; ten 24-bit accelerometers for early warning) • IGDAŞ Gas Shutoff Network (100 accelerometers to be installed in 2010 and integrated with IERREWS) • Structural Monitoring Arrays - Fatih Sultan Mehmet Suspension Bridge (1200m-long suspension bridge across the Bosphorus, five 3-component accelerometers + GPS sensors) - Hagia Sophia Array (1500-year-old historical edifice, 9 accelerometers) - Süleymaniye Mosque Array (450-year-old historical edifice,9 accelerometers) - Fatih Mosque Array (237-year-old historical edifice, 9 accelerometers) - Kanyon Building Array (high-rise office building, 5 accelerometers) - Isbank Tower Array (high-rise office building, 5 accelerometers) - ENRON Array (power generation facility, 4 acelerometers) - Mihrimah Sultan Mosque Array (450-year-old historical edifice,9 accelerometers + tiltmeters, to be installed in 2009) - Sultanahmet Mosque Array, (390-year-old historical edifice, 9 accelerometers + tiltmeters, to be installed in 2009) • Special Arrays - Atakoy Vertical Array (four 3-component accelerometers at 25, 50, 75, and 150 m depths) - Marmara Tube Tunnel (1400 m long submerged tunnel, 128 ch. accelerometric data, 24 ch. strain data, to be installed in 2010) - Air-Force Academy

  8. Vibrations of strongly irregular or fractal resonators

    Science.gov (United States)

    Sapoval, B.; Gobron, Th.

    1993-05-01

    It is shown on a specific example that fractal boundary conditions drastically alter the properties of wave excitations in space. The low-frequency part of the vibration spectrum of a finite-range fractal drum is computed using an analogy between the Helmoltz equation and the diffusion equation. The irregularity of the frontier is found to influence strongly the density of states at low frequency. The fractal perimeter generates a specific screening effect. Very near the frontier, the decrease of the wave form is related directly to the behavior of the harmonic measure. The possibility of localization of the vibrations is qualitatively discussed and we show that localized modes may exist at low frequencies if the geometrical structures possess narrow paths. Possible application of these results to the interpretation of thermal properties of binary glasses is briefly discussed.

  9. Strong Primordial Inhomogeneities and Galaxy Formation

    CERN Document Server

    Khlopov, M Ya; Sakharov, Alexander S

    2002-01-01

    The new element of theory of galaxy formation, strong primordial inhomogeneities, is shown to be a reflection of unstable large scale structures of topological defects, created in second order phase transitions in the inflationary Universe. In addition to {\\it archioles-like} large scale correlation of the primordial inhomogeneity of energy density of coherent scalar field oscillations, the same mechanism, based on the second order phase transitions on the inflational stage and the domain wall formation upon the end of inflation, leads to the formation of massive black hole clusters that can serve as nuclei for the future galaxies. The number of black holes with $M \\sim 100M_{\\odot}$ and above is comparable with the number of galaxies within the modern cosmological horizon. The primordial fractal structure of galaxies can find natural grounds in the framework of model we developed . The proposed approach offers the physical basis for new scenarios of galaxy formation in the Big Bang Universe.

  10. Transport phenomena in strongly correlated Fermi liquids

    CERN Document Server

    Kontani, Hiroshi

    2013-01-01

    In conventional metals, various transport coefficients are scaled according to the quasiparticle relaxation time, \\tau, which implies that the relaxation time approximation (RTA) holds well. However, such a simple scaling does not hold in many strongly correlated electron systems, reflecting their unique electronic states. The most famous example would be cuprate high-Tc superconductors (HTSCs), where almost all the transport coefficients exhibit a significant deviation from the RTA results. To better understand the origin of this discrepancy, we develop a method for calculating various transport coefficients beyond the RTA by employing field theoretical techniques. Near the magnetic quantum critical point, the current vertex correction (CVC), which describes the electron-electron scattering beyond the relaxation time approximation, gives rise to various anomalous transport phenomena. We explain anomalous transport phenomena in cuprate HTSCs and other metals near their magnetic or orbital quantum critical poi...

  11. Controlling strongly correlated dust clusters with lasers

    CERN Document Server

    Thomsen, Hauke; Bonitz, Michael; Schablinski, Jan; Block, Dietmar; Schella, André; Melzer, André

    2014-01-01

    The most attractive feature of dusty plasmas is the possibility to create strong correlations at room temperatures. At the same time, these plasmas allow for a precise diagnostics with single-particle resolution. From such measurements, the structural properties of finite two-dimensional (2D) clusters and three-dimensional (3D) spherical crystals in nearly harmonic traps-Yukawa balls-have been explored in great detail. Their structural properties-the shell compositions and the order within the shells-have been investigated and good agreement to theoretical predictions was found. Open questions on the agenda are the excitation behavior, the structural changes, and phase transitions that occur at elevated temperature. In order to increase the dust temperature in the experiment various techniques have been used. Among them, laser heating appears to have unique capabilities because it affects only the dust particles, leaving the lighter plasma components unchanged. Here we report on recent experimental results wh...

  12. Convex Modeling of Interactions with Strong Heredity

    Science.gov (United States)

    Haris, Asad; Witten, Daniela; Simon, Noah

    2015-01-01

    We consider the task of fitting a regression model involving interactions among a potentially large set of covariates, in which we wish to enforce strong heredity. We propose FAMILY, a very general framework for this task. Our proposal is a generalization of several existing methods, such as VANISH [Radchenko and James, 2010], hierNet [Bien et al., 2013], the all-pairs lasso, and the lasso using only main effects. It can be formulated as the solution to a convex optimization problem, which we solve using an efficient alternating directions method of multipliers (ADMM) algorithm. This algorithm has guaranteed convergence to the global optimum, can be easily specialized to any convex penalty function of interest, and allows for a straightforward extension to the setting of generalized linear models. We derive an unbiased estimator of the degrees of freedom of FAMILY, and explore its performance in a simulation study and on an HIV sequence data set. PMID:28316461

  13. Strongly nonlinear steepening of long interfacial waves

    Directory of Open Access Journals (Sweden)

    N. Zahibo

    2007-06-01

    Full Text Available The transformation of nonlinear long internal waves in a two-layer fluid is studied in the Boussinesq and rigid-lid approximation. Explicit analytic formulation of the evolution equation in terms of the Riemann invariants allows us to obtain analytical results characterizing strongly nonlinear wave steepening, including the spectral evolution. Effects manifesting the action of high nonlinear corrections of the model are highlighted. It is shown, in particular, that the breaking points on the wave profile may shift from the zero-crossing level. The wave steepening happens in a different way if the density jump is placed near the middle of the water bulk: then the wave deformation is almost symmetrical and two phases appear where the wave breaks.

  14. Competition between radiative and strong force decay

    Science.gov (United States)

    Tabor, Samuel

    2017-01-01

    For nuclear states unbound to neutron decay, radiative emission is often assumed to not dominate over neutron decay mediated by the far stronger strong interaction, except for very low neutron energies and high angular momentum barriers. Recent experimental investigations of 19O and 27 Mg populated in heavy-ion fusion-evaporation reactions have revealed predominantly gamma decays from a number of states unbound to neutron decay by up to 2 MeV. In most cases the angular momentum barrier is not sufficient to inhibit neutron decay enough to allow E-M decay with widths of up to an eV or so to win. Other inhibitions to particle decay, including low spectroscopic factors, will be discussed. Supported in part by NSF Grant No. 1401574.

  15. Strong quantum scarring by local impurities

    Science.gov (United States)

    Luukko, Perttu J. J.; Drury, Byron; Klales, Anna; Kaplan, Lev; Heller, Eric J.; Räsänen, Esa

    2016-11-01

    We discover and characterise strong quantum scars, or quantum eigenstates resembling classical periodic orbits, in two-dimensional quantum wells perturbed by local impurities. These scars are not explained by ordinary scar theory, which would require the existence of short, moderately unstable periodic orbits in the perturbed system. Instead, they are supported by classical resonances in the unperturbed system and the resulting quantum near-degeneracy. Even in the case of a large number of randomly scattered impurities, the scars prefer distinct orientations that extremise the overlap with the impurities. We demonstrate that these preferred orientations can be used for highly efficient transport of quantum wave packets across the perturbed potential landscape. Assisted by the scars, wave-packet recurrences are significantly stronger than in the unperturbed system. Together with the controllability of the preferred orientations, this property may be very useful for quantum transport applications.

  16. Chirally symmetric strong and electroweak interactions

    Science.gov (United States)

    Rajpoot, Subhash

    1988-07-01

    Strong and electroweak interactions may be a relic of the spontaneous breakdown of a chirally symmetric colour-flavour gauge group. The minimum possibility of such a structure that is symmetric between left and right is SU(3) L×SU(3) R×SU(2) L×SU(2) R×U(1) B- L where quantum chromodynamics originates in the chiral colour group SU(3) L×SU(3) R and the electroweak interaction originates in the ambidextrous electroweak interaction group SU L×SU(2) R×U(1) B- L. The chiral anomalies are cancelled by adding a set of fermions that transform as singlets under the weak interaction group SU(2) L×SU(2) R. This model requires only three Higgs representations to break the proposed gauge symmetry to SU(3) C×U(1) em and give masses to all the quarks and leptons of the theory. All fermion masses are “see-saw” masses.

  17. Strongly Interacting Matter at High Energy Density

    Energy Technology Data Exchange (ETDEWEB)

    McLerran,L.

    2008-09-07

    This lecture concerns the properties of strongly interacting matter (which is described by Quantum Chromodynamics) at very high energy density. I review the properties of matter at high temperature, discussing the deconfinement phase transition. At high baryon density and low temperature, large N{sub c} arguments are developed which suggest that high baryonic density matter is a third form of matter, Quarkyonic Matter, that is distinct from confined hadronic matter and deconfined matter. I finally discuss the Color Glass Condensate which controls the high energy limit of QCD, and forms the low x part of a hadron wavefunction. The Glasma is introduced as matter formed by the Color Glass Condensate which eventually thermalizes into a Quark Gluon Plasma.

  18. Overcoming strong metastabilities with the LLR method

    CERN Document Server

    Lucini, Biagio; Langfeld, Kurt

    2016-01-01

    In previous work, it has been shown that the recently proposed LLR method is very efficient at overcoming strong metastabilities that arise near first-order phase transition points. Here we present a systematic study of the performance of the algorithm near (pseudo-)critical points for $q$-state Potts models with $q$ as large as 20, in two and three dimensions. In particular, we shall focus our study on the ergodicity of the replica exchange step and the underlying physical mechanism. When compared with both analytical and numerical results present in the literature, our determinations of thermodynamic observables (including the order-disorder interface tension at criticality) show an impressive degree of relative accuracy (up to $2.5 \\times 10^{-6}$), which confirms the reliability and the efficiency of the proposed approach.

  19. Strong curvature effects in Neumann wave problems

    Science.gov (United States)

    Willatzen, M.; Pors, A.; Gravesen, J.

    2012-08-01

    Waveguide phenomena play a major role in basic sciences and engineering. The Helmholtz equation is the governing equation for the electric field in electromagnetic wave propagation and the acoustic pressure in the study of pressure dynamics. The Schrödinger equation simplifies to the Helmholtz equation for a quantum-mechanical particle confined by infinite barriers relevant in semiconductor physics. With this in mind and the interest to tailor waveguides towards a desired spectrum and modal pattern structure in classical structures and nanostructures, it becomes increasingly important to understand the influence of curvature effects in waveguides. In this work, we demonstrate analytically strong curvature effects for the eigenvalue spectrum of the Helmholtz equation with Neumann boundary conditions in cases where the waveguide cross section is a circular sector. It is found that the linear-in-curvature contribution originates from parity symmetry breaking of eigenstates in circular-sector tori and hence vanishes in a torus with a complete circular cross section. The same strong curvature effect is not present in waveguides subject to Dirichlet boundary conditions where curvature contributions contribute to second-order in the curvature only. We demonstrate this finding by considering wave propagation in a circular-sector torus corresponding to Neumann and Dirichlet boundary conditions, respectively. Results for relative eigenfrequency shifts and modes are determined and compared with three-dimensional finite element method results. Good agreement is found between the present analytical method using a combination of differential geometry with perturbation theory and finite element results for a large range of curvature ratios.

  20. Strong curvature effects in Neumann wave problems

    Energy Technology Data Exchange (ETDEWEB)

    Willatzen, M.; Pors, A. [Mads Clausen Institute, University of Southern Denmark, Alsion 2, DK-6400 Sonderborg (Denmark); Gravesen, J. [Department of Mathematics, Technical University of Denmark, Matematiktorvet, DK-2800 Kgs. Lyngby (Denmark)

    2012-08-15

    Waveguide phenomena play a major role in basic sciences and engineering. The Helmholtz equation is the governing equation for the electric field in electromagnetic wave propagation and the acoustic pressure in the study of pressure dynamics. The Schroedinger equation simplifies to the Helmholtz equation for a quantum-mechanical particle confined by infinite barriers relevant in semiconductor physics. With this in mind and the interest to tailor waveguides towards a desired spectrum and modal pattern structure in classical structures and nanostructures, it becomes increasingly important to understand the influence of curvature effects in waveguides. In this work, we demonstrate analytically strong curvature effects for the eigenvalue spectrum of the Helmholtz equation with Neumann boundary conditions in cases where the waveguide cross section is a circular sector. It is found that the linear-in-curvature contribution originates from parity symmetry breaking of eigenstates in circular-sector tori and hence vanishes in a torus with a complete circular cross section. The same strong curvature effect is not present in waveguides subject to Dirichlet boundary conditions where curvature contributions contribute to second-order in the curvature only. We demonstrate this finding by considering wave propagation in a circular-sector torus corresponding to Neumann and Dirichlet boundary conditions, respectively. Results for relative eigenfrequency shifts and modes are determined and compared with three-dimensional finite element method results. Good agreement is found between the present analytical method using a combination of differential geometry with perturbation theory and finite element results for a large range of curvature ratios.

  1. Is It Possible to Predict Strong Earthquakes?

    Science.gov (United States)

    Polyakov, Y. S.; Ryabinin, G. V.; Solovyeva, A. B.; Timashev, S. F.

    2015-07-01

    The possibility of earthquake prediction is one of the key open questions in modern geophysics. We propose an approach based on the analysis of common short-term candidate precursors (2 weeks to 3 months prior to strong earthquake) with the subsequent processing of brain activity signals generated in specific types of rats (kept in laboratory settings) who reportedly sense an impending earthquake a few days prior to the event. We illustrate the identification of short-term precursors using the groundwater sodium-ion concentration data in the time frame from 2010 to 2014 (a major earthquake occurred on 28 February 2013) recorded at two different sites in the southeastern part of the Kamchatka Peninsula, Russia. The candidate precursors are observed as synchronized peaks in the nonstationarity factors, introduced within the flicker-noise spectroscopy framework for signal processing, for the high-frequency component of both time series. These peaks correspond to the local reorganizations of the underlying geophysical system that are believed to precede strong earthquakes. The rodent brain activity signals are selected as potential "immediate" (up to 2 weeks) deterministic precursors because of the recent scientific reports confirming that rodents sense imminent earthquakes and the population-genetic model of K irshvink (Soc Am 90, 312-323, 2000) showing how a reliable genetic seismic escape response system may have developed over the period of several hundred million years in certain animals. The use of brain activity signals, such as electroencephalograms, in contrast to conventional abnormal animal behavior observations, enables one to apply the standard "input-sensor-response" approach to determine what input signals trigger specific seismic escape brain activity responses.

  2. The effect of provider- and workflow-focused strategies for guideline implementation on provider acceptance

    Directory of Open Access Journals (Sweden)

    Ramanujam Rangaraj

    2009-10-01

    Full Text Available Abstract Background The effective implementation of clinical practice guidelines (CPGs depends critically on the extent to which the strategies that are deployed for implementing the guidelines promote provider acceptance of CPGs. Such implementation strategies can be classified into two types based on whether they primarily target providers (e.g., academic detailing, grand rounds presentations or the work context (e.g., computer reminders, modifications to forms. This study investigated the independent and joint effects of these two types of implementation strategies on provider acceptance of CPGs. Methods Surveys were mailed to a national sample of providers (primary care physicians, physician assistants, nurses, and nurse practitioners and quality managers selected from Veterans Affairs Medical Centers (VAMCs. A total of 2,438 providers and 242 quality managers from 123 VAMCs participated. Survey items measured implementation strategies and provider acceptance (e.g., guideline-related knowledge, attitudes, and adherence for three sets of CPGs--chronic obstructive pulmonary disease, chronic heart failure, and major depressive disorder. The relationships between implementation strategy types and provider acceptance were tested using multi-level analytic models. Results For all three CPGs, provider acceptance increased with the number of implementation strategies of either type. Moreover, the number of workflow-focused strategies compensated (contributing more strongly to provider acceptance when few provider-focused strategies were used. Conclusion Provider acceptance of CPGs depends on the type of implementation strategies used. Implementation effectiveness can be improved by using both workflow-focused as well as provider-focused strategies.

  3. Finding communities in networks in the strong and almost-strong sense

    Science.gov (United States)

    Cafieri, Sonia; Caporossi, Gilles; Hansen, Pierre; Perron, Sylvain; Costa, Alberto

    2012-04-01

    Finding communities, or clusters or modules, in networks can be done by optimizing an objective function defined globally and/or by specifying conditions which must be satisfied by all communities. Radicchi [Proc. Natl. Acad. Sci. USAPNASA60027-842410.1073/pnas.0400054101 101, 2658 (2004)] define a susbset of vertices of a network to be a community in the strong sense if each vertex of that subset has a larger inner degree than its outer degree. A partition in the strong sense has only strong communities. In this paper we first define an enumerative algorithm to list all partitions in the strong sense of a network of moderate size. The results of this algorithm are given for the Zachary karate club data set, which is solved by hand, as well as for several well-known real-world problems of the literature. Moreover, this algorithm is slightly modified in order to apply it to larger networks, keeping only partitions with the largest number of communities. It is shown that some of the partitions obtained are informative, although they often have only a few communities, while they fail to give any information in other cases having only one community. It appears that degree 2 vertices play a big role in forcing large inhomogeneous communities. Therefore, a weakening of the strong condition is proposed and explored: we define a partition in the almost-strong sense by substituting a nonstrict inequality to a strict one in the definition of strong community for all vertices of degree 2. Results, for the same set of problems as before, then give partitions with a larger number of communities and are more informative.

  4. Strong Gravity Approach to QCD and General Relativity

    CERN Document Server

    Akinto, O F

    2016-01-01

    A systematic study of the Weyl-type / Yang-Mills-type action possessing local conformal invariance and quadratic curvature is undertaken. The dynamical breaking of this conformal invariance / scale invariance induces general relativity (GR) as an effective long distance limit of the theory. We prove that the corresponding field equations of the theory have the linearly rising potential, which naturally possesses asymptotic freedom and color confinement properties of quantum chromodynamics (QCD). Solutions to the neutrino mass and dark energy problems come as free gifts of this formulation. This approach provides a strong gravity basis for the unification of quantum Yang-Mills theory (QYMT) with Einstein GR.

  5. Efficient simulation of strong system-environment interactions.

    Science.gov (United States)

    Prior, Javier; Chin, Alex W; Huelga, Susana F; Plenio, Martin B

    2010-07-30

    Multicomponent quantum systems in strong interaction with their environment are receiving increasing attention due to their importance in a variety of contexts, ranging from solid state quantum information processing to the quantum dynamics of biomolecular aggregates. Unfortunately, these systems are difficult to simulate as the system-bath interactions cannot be treated perturbatively and standard approaches are invalid or inefficient. Here we combine the time-dependent density matrix renormalization group with techniques from the theory of orthogonal polynomials to provide an efficient method for simulating open quantum systems, including spin-boson models and their generalizations to multicomponent systems.

  6. Efficient simulation of strong system-environment interactions

    CERN Document Server

    Prior, Javier; Huelga, Susana F; Plenio, Martin B

    2010-01-01

    Multi-component quantum systems in strong interaction with their environment are receiving increasing attention due to their importance in a variety of contexts, ranging from solid state quantum information processing to the quantum dynamics of bio-molecular aggregates. Unfortunately, these systems are difficult to simulate as the system-bath interactions cannot be treated perturbatively and standard approaches are invalid or inefficient. Here we combine the time dependent density matrix renormalization group methods with techniques from the theory of orthogonal polynomials to provide an efficient method for simulating open quantum systems, including spin-boson models and their generalisations to multi-component systems.

  7. REGENABATH -- novel regeneration methods for strongly acidic metal treatment baths

    Energy Technology Data Exchange (ETDEWEB)

    Collins, J. [Capenhurst Tech Limited, Capenhurst, Chester (United Kingdom); Hendou, M. [Lacaze S.A., Leyme (France)

    2001-07-01

    This European Union-sponsored project is designed to investigate the potential of integrating existing and novel technologies for use in regenerating strong acids used in the treatment of metal surfaces. At present, the acid bath must be bled off to remove the metal content, or the whole bath may be periodically discarded, a process which is hazardous, costly and injurious to the environment. This paper provides a full description of the project objectives, expected results, challenges, proposed applications and technology transfer potential. It is expected that the techniques developed can be extended to other highly acidic waste streams generated by metallurgical facilities.

  8. Thermodynamics of strong-interaction matter from Lattice QCD

    CERN Document Server

    Ding, Heng-Tong; Mukherjee, Swagato

    2015-01-01

    We review results from lattice QCD calculations on the thermodynamics of strong-interaction matter with emphasis on input these calculations can provide to the exploration of the phase diagram and properties of hot and dense matter created in heavy ion experiments. This review is organized as follows: 1) Introduction, 2) QCD thermodynamics on the lattice, 3) QCD phase diagram at high temperature, 4) Bulk thermodynamics, 5) Fluctuations of conserved charges, 6) Transport properties, 7) Open heavy flavors and heavy quarkonia, 8) QCD in external magnetic fields, 9) Summary.

  9. From Strong Amalgamability to Modularity of Quantifier-Free Interpolation

    CERN Document Server

    Bruttomesso, Roberto; Ranise, Silvio

    2012-01-01

    The use of interpolants in verification is gaining more and more importance. Since theories used in applications are usually obtained as (disjoint) combinations of simpler theories, it is important to modularly re-use interpolation algorithms for the component theories. We show that a sufficient and necessary condition to do this for quantifier-free interpolation is that the component theories have the 'strong (sub-)amalgamation' property. Then, we provide an equivalent syntactic characterization, identify a sufficient condition, and design a combined quantifier-free interpolation algorithm capable of handling both convex and non-convex theories, that subsumes and extends most existing work on combined interpolation.

  10. Nonlinear Principal Component Analysis Using Strong Tracking Filter

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The paper analyzes the problem of blind source separation (BSS) based on the nonlinear principal component analysis (NPCA) criterion. An adaptive strong tracking filter (STF) based algorithm was developed, which is immune to system model mismatches. Simulations demonstrate that the algorithm converges quickly and has satisfactory steady-state accuracy. The Kalman filtering algorithm and the recursive leastsquares type algorithm are shown to be special cases of the STF algorithm. Since the forgetting factor is adaptively updated by adjustment of the Kalman gain, the STF scheme provides more powerful tracking capability than the Kalman filtering algorithm and recursive least-squares algorithm.

  11. Strong rules for discarding predictors in lasso-type problems

    CERN Document Server

    Tibshirani, Robert; Friedman, Jerome; Hastie, Trevor

    2010-01-01

    We consider rules for discarding predictors in lasso regression and related problems, for computational efficiency. El Ghaoui et al (2010) propose "SAFE" rules that guarantee that a coefficient will be zero in the solution, based on the inner products of each predictor with the outcome. In this paper we propose strong rules that are not foolproof but rarely fail in practice. These can be complemented with simple checks of the Karush- Kuhn-Tucker (KKT) conditions to provide safe rules that offer substantial speed and space savings in a variety of statistical convex optimization problems.

  12. Multiphoton above threshold effects in strong-field fragmentation

    DEFF Research Database (Denmark)

    B Madsen, C; Anis, F; B Madsen, L

    2012-01-01

    We present a study of multiphoton dissociative ionization from molecules. By solving the time-dependent Schrödinger equation for H2+ and projecting the solution onto double continuum scattering states, we observe the correlated electron-nuclear ionization dynamics in detail. We show—for the first...... time—how multiphoton structure prevails as long as one accounts for the energies of all the fragments. Our current work provides a new avenue to analyze strong-field fragmentation that leads to a deeper understanding of the correlated molecular dynamics....

  13. Design of Pulsed Strong Magnetic Fields Generator and Preliminary Application

    Institute of Scientific and Technical Information of China (English)

    WEN Jun; QU Xue-min; WANG Xi-gang; LONG Kai-ping

    2015-01-01

    Objective: This paper aims to designing a pulsed strong magnetic fields generator. Methods: A large value capacitor was used to store electric energy, coil was used for producing magnetic fields, main control, circuit control charge, sampling, discharge, etc. Results: The generator provided a pulsed magnetic field with the ampli-tude of intensity from 0.1-2 T and variable time interval of pulse from 4 s-1 min. It was not only to be operated easily but also performed reliably. Conclusion:The generator will be applied in special clinical diagnosis, therapy and other fields.

  14. Black hole thermodynamics from calculations in strongly coupled gauge theory.

    Science.gov (United States)

    Kabat, D; Lifschytz, G; Lowe, D A

    2001-02-19

    We develop an approximation scheme for the quantum mechanics of N D0-branes at finite temperature in the 't Hooft large- N limit. The entropy of the quantum mechanics calculated using this approximation agrees well with the Bekenstein-Hawking entropy of a ten-dimensional nonextremal black hole with 0-brane charge. This result is in accordance with the duality conjectured by Itzhaki, Maldacena, Sonnenschein, and Yankielowicz [Phys. Rev. D 58, 046004 (1998)]. Our approximation scheme provides a model for the density matrix which describes a black hole in the strongly coupled quantum mechanics.

  15. Strong Motion Seismograph Based On MEMS Accelerometer

    Science.gov (United States)

    Teng, Y.; Hu, X.

    2013-12-01

    The MEMS strong motion seismograph we developed used the modularization method to design its software and hardware.It can fit various needs in different application situation.The hardware of the instrument is composed of a MEMS accelerometer,a control processor system,a data-storage system,a wired real-time data transmission system by IP network,a wireless data transmission module by 3G broadband,a GPS calibration module and power supply system with a large-volumn lithium battery in it. Among it,the seismograph's sensor adopted a three-axis with 14-bit high resolution and digital output MEMS accelerometer.Its noise level just reach about 99μg/√Hz and ×2g to ×8g dynamically selectable full-scale.Its output data rates from 1.56Hz to 800Hz. Its maximum current consumption is merely 165μA,and the device is so small that it is available in a 3mm×3mm×1mm QFN package. Furthermore,there is access to both low pass filtered data as well as high pass filtered data,which minimizes the data analysis required for earthquake signal detection. So,the data post-processing can be simplified. Controlling process system adopts a 32-bit low power consumption embedded ARM9 processor-S3C2440 and is based on the Linux operation system.The processor's operating clock at 400MHz.The controlling system's main memory is a 64MB SDRAM with a 256MB flash-memory.Besides,an external high-capacity SD card data memory can be easily added.So the system can meet the requirements for data acquisition,data processing,data transmission,data storage,and so on. Both wired and wireless network can satisfy remote real-time monitoring, data transmission,system maintenance,status monitoring or updating software.Linux was embedded and multi-layer designed conception was used.The code, including sensor hardware driver,the data acquisition,earthquake setting out and so on,was written on medium layer.The hardware driver consist of IIC-Bus interface driver, IO driver and asynchronous notification driver. The

  16. Roulettes: a weak lensing formalism for strong lensing: I. Overview

    Science.gov (United States)

    Clarkson, Chris

    2016-08-01

    We present a new perspective on gravitational lensing. We describe a new extension of the weak lensing formalism capable of describing strongly lensed images. By integrating the nonlinear geodesic deviation equation, the amplification matrix of weak lensing is generalised to a sum over independent amplification tensors of increasing rank. We show how an image distorted by a generic lens may be constructed as a sum over ‘roulettes’, which are the natural curves associated with the independent spin modes of the amplification tensors. Highly distorted images can be constructed even for large sources observed near or within the Einstein radius of a lens where the shear and convergence are large. The amplitude of each roulette is formed from a sum over appropriate derivatives of the lensing potential. Consequently, measuring these individual roulettes for images around a lens gives a new way to reconstruct a strong lens mass distribution without requiring a lens model. This formalism generalises the convergence, shear and flexion of weak lensing to arbitrary order, and provides a unified bridge between the strong and weak lensing regimes. This overview paper is accompanied by a much more detailed paper II, arXiv:1603.04652.

  17. Parametric optimization of optical devices based on strong photonic localization

    Science.gov (United States)

    Gui, Minmin; Yang, Xiangbo

    2017-07-01

    Symmetric two-segment-connected triangular defect waveguide networks (STSCTDWNs) can produce strong photonic localization, which is useful for designing highly efficient energy storage devices, high power superluminescent light emitting diodes, all-optical switches, and more. Although STSCTDWNs have been studied in previous works, in this paper we systematically optimize the parameters of STSCTDWNs to further enhance photonic localization so that the function of optical devices based on strong photonic localization can be improved. When optimizing the parameters, we find a linear relationship between the logarithm of photonic localization and the broken degree of networks. Furthermore, the slope and intercept of the linear relationship are larger than previous results. This means that the increasing speed of photonic localization is improved. The largest intensity of photonic localizations can reach 1036, which is 16 orders of magnitude larger than previous reported results. These optimized networks provide practical solutions for all optical devices based on strong photonic localization in the low frequency range, such as nanostructured devices.

  18. Electronic properties of strongly correlated layered oxides

    Science.gov (United States)

    Lee, Wei-Cheng

    The two-dimensional electronic systems (2DESs) have kept surprising physicists for the last few decades. Examples include the integer and fractional quantum Hall effects, cuprate superconductivity, and graphene. This thesis is intended to develop suitable theoretical tools which can be generalized to study new types of 2DESs with strong correlation feature. The first part of this thesis describes the investigation of heterostructures made by Mott insulators. This work is mostly motivated by the significant improvement of techniques for layer-by-layer growth of transition metal oxides in the last few years. We construct a toy model based on generalized Hubbard model complemented with long-ranged Coulomb interaction, and we study it by Hartree-Fock theory, dynamical mean-field theory, and Thomas-Fermi theory. We argue that interesting 2D strongly correlated electronic systems can be created in such heterostructures under several conditions. Since these 2D systems are formed entirely due to the gap generated by electron-electron interaction, they are not addiabatically connected to a noninteracting electron states. This feature makes these 2D systems distinguish from the ones created in semiconductor heterostructures, and they may be potential systems having non-Fermi liquid behaviors. The second part of this thesis is devoted to the study of collective excitations in high-temperature superconductors. One important achievement in this work is to develop a time-dependent mean-field theory for t -- U -- J -- V model, an effective low energy model for cuprates. The time-dependent mean-field theory is proven to be identical to the generalized random-phase approximation (GRPA) which includes both the bubble and ladder diagrams. We propose that the famous 41 meV magnetic resonance mode observed in the inelastic neutron scattering measurements is a collective mode arising from a conjugation relation, which has been overlooked in previous work, between the antiferromagnetic

  19. Wind Turbine Providing Grid Support

    DEFF Research Database (Denmark)

    2011-01-01

    A variable speed wind turbine is arranged to provide additional electrical power to counteract non-periodic disturbances in an electrical grid. A controller monitors events indicating a need to increase the electrical output power from the wind turbine to the electrical grid. The controller...... is arranged to control the wind turbine as follows: after an indicating event has been detected, the wind turbine enters an overproduction period in which the electrical output power is increased, wherein the additional electrical output power is taken from kinetic energy stored in the rotor and without...... changing the operation of the wind turbine to a more efficient working point.; When the rotational speed of the rotor reaches a minimum value, the wind turbine enters a recovery period to re-accelerate the rotor to the nominal rotational speed while further contributing to the stability of the electrical...

  20. Using of Automatic Metadata Providing

    Directory of Open Access Journals (Sweden)

    P. Šimek

    2013-12-01

    Full Text Available The paper deals with the necessity of systemic solution for metadata providing by local archives into central repositories and its subsequent implementatiton by the Department of Information Technologies, Faculty of Economics and Management, Czech University of Life Sciences in Prague, for the needs of the agrarian WWW AGRIS portal. The system supports the OAI-PMH (Open Archive Initiative – Protocol for Metadata Harvesting protocol, several metadata formats and thesauri and meets the quality requirements: functionality, high level of reliability, applicability, sustainability and transferability. The SW application for the OAI-PMH requests’ servicing is run in the setting of the WWW Apache server using an efficient PHP framework Nette and database dibi layer.

  1. HTE & CNTAC Form Strong Strategic Partnership

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Huntsman Textile Effects (HTE) and the China National Textile and Apparel Council (CNTAC) has joined forces as strategic partners to further efforts in providing total textile solutions that will deliver and enhance economic and environmental sustainability for the China textile industry.

  2. A Strong Kind of Riemann Integrability

    Science.gov (United States)

    Thomson, Brian S.

    2012-01-01

    The usual definition of the Riemann integral as a limit of Riemann sums can be strengthened to demand more of the function to be integrated. This super-Riemann integrability has interesting properties and provides an easy proof of a simple change of variables formula and a novel characterization of derivatives. This theory offers teachers and…

  3. Internal bremsstrahlung of strongly interacting charged particles

    Energy Technology Data Exchange (ETDEWEB)

    Kurgalin, S. D. [Voronezh State University (Russian Federation); Tchuvil’sky, Yu. M., E-mail: tchuvl@nucl-th.sinp.msu.ru [Moscow State University, Skobeltsyn Institute of Nuclear Physics (Russian Federation); Churakova, T. A. [Voronezh State University (Russian Federation)

    2016-11-15

    A universal theoretical model intended for calculating internal-bremsstrahlung spectra is proposed. In this model, which can be applied to describing nuclear decays of various type (such as alpha decay, cluster decay, and proton emission), use is made of realistic nucleus–nucleus potentials. Theoretical internal-bremsstrahlung spectra were obtained for the alpha decay of the {sup 214}Po nucleus, as well as for the decay of the {sup 222}Ra nucleus via the emission of a {sup 14}C cluster and for the decay of the {sup 113}Cs nucleus via proton emission, and the properties of these spectra were studied. The contributions of various regions (internal, subbarrier, and external) to the internal-bremsstrahlung amplitude were analyzed in detail. It is shown that the contribution of the internal region to the amplitude for internal bremsstrahlung generated in nuclear decay via proton emission is quite large, but that this is not so for alpha decay and decay via cluster emission. Thus, a process in which strong interaction of nuclear particles affects the internal-bremsstrahlung spectrum if found.

  4. Strong washout approximation to resonant leptogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Garbrecht, Bjoern; Gautier, Florian; Klaric, Juraj [Physik Department T70, James-Franck-Strasse, Techniche Universitaet Muenchen, 85748 Garching (Germany)

    2016-07-01

    We study resonant Leptogenesis with two sterile neutrinos with masses M{sub 1} and M{sub 2}, Yukawa couplings Y{sub 1} and Y{sub 2}, and a single active flavor. Specifically, we focus on the strong washout regime, where the decay width dominates the mass splitting of the two sterile neutrinos. We show that one can approximate the effective decay asymmetry by it's late time limit ε = X sin(2 φ)/(X{sup 2}+sin{sup 2}φ), where X=8 π Δ/(vertical stroke Y{sub 1} vertical stroke {sup 2}+ vertical stroke Y{sub 2} vertical stroke {sup 2}), Δ=4(M{sub 1}-M{sub 2})/(M{sub 1}+M{sub 2}), and φ=arg(Y{sub 2}/Y{sub 1}), and establish criteria for the validity of this approximation. We compare the approximate results with numerical ones, obtained by solving the mixing and oscillations of the sterile neutrinos. We generalize the formula to the case of several active flavors, and demonstrate how it can be used to calculate the lepton asymmetry in phenomenological scenarios which are in agreement with the neutrino oscillation data. We find that that using the late time limit is an applicable approximation throughout the phenomenologically viable parameter space.

  5. Thermal infrared anomalies of several strong earthquakes.

    Science.gov (United States)

    Wei, Congxin; Zhang, Yuansheng; Guo, Xiao; Hui, Shaoxing; Qin, Manzhong; Zhang, Ying

    2013-01-01

    In the history of earthquake thermal infrared research, it is undeniable that before and after strong earthquakes there are significant thermal infrared anomalies which have been interpreted as preseismic precursor in earthquake prediction and forecasting. In this paper, we studied the characteristics of thermal radiation observed before and after the 8 great earthquakes with magnitude up to Ms7.0 by using the satellite infrared remote sensing information. We used new types of data and method to extract the useful anomaly information. Based on the analyses of 8 earthquakes, we got the results as follows. (1) There are significant thermal radiation anomalies before and after earthquakes for all cases. The overall performance of anomalies includes two main stages: expanding first and narrowing later. We easily extracted and identified such seismic anomalies by method of "time-frequency relative power spectrum." (2) There exist evident and different characteristic periods and magnitudes of thermal abnormal radiation for each case. (3) Thermal radiation anomalies are closely related to the geological structure. (4) Thermal radiation has obvious characteristics in abnormal duration, range, and morphology. In summary, we should be sure that earthquake thermal infrared anomalies as useful earthquake precursor can be used in earthquake prediction and forecasting.

  6. Truly Minimal Unification Asymptotically Strong Panacea ?

    CERN Document Server

    Aulakh, Charanjit S

    2002-01-01

    We propose Susy GUTs have a UV {\\it{attractor}} at $E\\sim \\Lambda_{cU} \\sim 10^{17} GeV $ where gauge symmetries ``confine'' forming singlet condensates at scales $E\\sim\\Lambda_{cU}$. The length $l_U\\sim \\Lambda_{cU}^{-1}$ characterizies the {\\it{size}} of gauge non- singlet particles yielding a picture dual to the Dual Standard model of Vachaspati. This Asymptotic Slavery (AS) fixed point is driven by realistic Fermion Mass(FM) Higgs content which implies AS. This defines a dynamical morphogenetic scenario dependent on the dynamics of UV strong N=1 Susy Gauge-Chiral(SGC) theories. Such systems are already understood in the AF case but ignored in the AS case. Analogy to the AFSGC suggests the perturbative SM gauge group of the Grand Desert confines at GUT scales i.e GUT symmetry is ``non-restored''. Restoration before confinement and self-inconsistency are the two other (less likely) logical possibilities. Truly Minimal (TM) SU(5) and SO(10) models with matter and FM Higgs only are defined; AM (adjoint multip...

  7. Iron Line Profiles in Strong Gravity

    CERN Document Server

    Beckwith, K; Beckwith, Kris; Done, Chris

    2004-01-01

    We describe a new code which can accurately calculate the relativistic effects which distort the emission from an accretion disc around a black hole. We compare our results for a disk from 6-20r_g in both Schwarzchild and extreme Kerr spacetimes with the two line profile codes which are on general release in the XSPEC spectral fitting package. These are generally accurate at the 10-20% level for this range of radii, but have some drawbacks in terms of assumptions and/or resolution. In particular we show that the assumed form of the angular emissivity law (limb darkening or brightening) can make significant changes to the derived line profile. Lightbending effects are never negligible at these radii, so the observed line is produced from a range of different emitted angles, and this can affect the derived radial emissivity law. The line profile is not simply determined by the well defined (but numerically difficult) physical effects of strong gravity, but is also dependent on the poorly known astrophysics of t...

  8. Strongly magnetized rotating dipole in general relativity

    Science.gov (United States)

    Pétri, J.

    2016-10-01

    Context. Electromagnetic waves arise in many areas of physics. Solutions are difficult to find in the general case. Aims: We numerically integrate Maxwell equations in a 3D spherical polar coordinate system. Methods: Straightforward finite difference methods would lead to a coordinate singularity along the polar axis. Spectral methods are better suited for such artificial singularities that are related to the choice of a coordinate system. When the radiating object rotates like a star, for example, special classes of solutions to Maxwell equations are worthwhile to study, such as quasi-stationary regimes. Moreover, in high-energy astrophysics, strong gravitational and magnetic fields are present especially around rotating neutron stars. Results: To study such systems, we designed an algorithm to solve the time-dependent Maxwell equations in spherical polar coordinates including general relativity and quantum electrodynamical corrections to leading order. As a diagnostic, we computed the spin-down luminosity expected for these stars and compared it to the classical or non-relativistic and non-quantum mechanical results. Conclusions: Quantum electrodynamics leads to an irrelevant change in the spin-down luminosity even for a magnetic field of about the critical value of 4.4 × 109 T. Therefore the braking index remains close to its value for a point dipole in vacuum, namely n = 3. The same conclusion holds for a general-relativistic quantum electrodynamically corrected force-free magnetosphere.

  9. Quark matter under strong magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    Peres Menezes, Debora [Universidade Federal de Santa Catarina, Depto de Fisica - CFM, Florianopolis, SC (Brazil); Laercio Lopes, Luiz [Universidade Federal de Santa Catarina, Depto de Fisica - CFM, Florianopolis, SC (Brazil); Campus VIII, Centro Federal de Educacao Tecnologica de Minas Gerais, Varginha, MG (Brazil)

    2016-02-15

    We revisit three of the mathematical formalisms used to describe magnetized quark matter in compact objects within the MIT and the Nambu-Jona-Lasinio models and then compare their results. The tree formalisms are based on 1) isotropic equations of state, 2) anisotropic equations of state with different parallel and perpendicular pressures and 3) the assumption of a chaotic field approximation that results in a truly isotropic equation of state. We have seen that the magnetization obtained with both models is very different: while the MIT model produces well-behaved curves that are always positive for large magnetic fields, the NJL model yields a magnetization with lots of spikes and negative values. This fact has strong consequences on the results based on the existence of anisotropic equations of state. We have also seen that, while the isotropic formalism results in maximum stellar masses that increase considerably when the magnetic fields increase, maximum masses obtained with the chaotic field approximation never vary more than 5.5%. The effect of the magnetic field on the radii is opposed in the MIT and NJL models: with both formalisms, isotropic and chaotic field approximation, for a fixed mass, the radii increase with the increase of the magnetic field in the MIT bag model and decrease in the NJL, the radii of quark stars described by the NJL model being smaller than the ones described by the MIT model. (orig.)

  10. Strong thin membrane structure. [solar sails

    Science.gov (United States)

    Frazer, R. E. (Inventor)

    1979-01-01

    A continuous process is described for producing strong lightweight structures for use as solar sails for spacecraft propulsion by radiation pressure. A thin reflective coating, such as aluminum, is applied to a rotating cylinder. A nylon mesh, applied over the aluminum coating, is then coated with a polymerizing material such as a para-xylylene monomer gas to polymerize as a film bound to the mesh and the aluminum. An emissivity increasing material such as chromium or silicon monoxide is applied to the polymer film to disperse such material colloidally into the growing polymer film, or to the final polymer film. The resulting membrane structure is then removed from the cylinder. Alternately, the membrane structure can be formed by etching a substrate in the form of an organic film such as a polymide, or a metal foil, to remove material from the substrate and reduce its thickness. A thin reflective coating (aluminum) is applied on one side of the substrate, and an emissivity increasing coating is applied on the reverse side of the substrate.

  11. Strong Higgs Interactions at a Linear Collider

    CERN Document Server

    Contino, Roberto; Pappadopulo, Duccio; Rattazzi, Riccardo; Thamm, Andrea

    2014-01-01

    We study the impact of Higgs precision measurements at a high-energy and high-luminosity linear electron positron collider, such as CLIC or the ILC, on the parameter space of a strongly interacting Higgs boson. Some combination of anomalous couplings are already tightly constrained by current fits to electroweak observables. However, even small deviations in the cross sections of single and double Higgs production, or the mere detection of a triple Higgs final state, can help establish whether it is a composite state and whether or not it emerges as a pseudo-Nambu-Goldstone boson from an underlying broken symmetry. We obtain an estimate of the ILC and CLIC sensitivities on the anomalous Higgs couplings from a study of WW scattering and hh production which can be translated into a sensitivity on the compositeness scale 4\\pi f, or equivalently on the degree of compositeness \\xi=v^2/f^2. We summarize the current experimental constraints, from electroweak data and direct resonance searches, and the expected reach...

  12. Grassy Silica Nanoribbons and Strong Blue Luminescence

    Science.gov (United States)

    Wang, Shengping; Xie, Shuang; Huang, Guowei; Guo, Hongxuan; Cho, Yujin; Chen, Jun; Fujita, Daisuke; Xu, Mingsheng

    2016-09-01

    Silicon dioxide (SiO2) is one of the key materials in many modern technological applications such as in metal oxide semiconductor transistors, photovoltaic solar cells, pollution removal, and biomedicine. We report the accidental discovery of free-standing grassy silica nanoribbons directly grown on SiO2/Si platform which is commonly used for field-effect transistors fabrication without other precursor. We investigate the formation mechanism of this novel silica nanostructure that has not been previously documented. The silica nanoribbons are flexible and can be manipulated by electron-beam. The silica nanoribbons exhibit strong blue emission at about 467 nm, together with UV and red emissions as investigated by cathodoluminescence technique. The origins of the luminescence are attributed to various defects in the silica nanoribbons; and the intensity change of the blue emission and green emission at about 550 nm is discussed in the frame of the defect density. Our study may lead to rational design of the new silica-based materials for a wide range of applications.

  13. DYNAMICS OF STRONGLY TWISTED RELATIVISTIC MAGNETOSPHERES

    Energy Technology Data Exchange (ETDEWEB)

    Parfrey, Kyle [Astronomy Department, Columbia University, 550 West 120th Street, New York, NY 10027 (United States); Beloborodov, Andrei M.; Hui, Lam, E-mail: parfrey@astro.princeton.edu [Physics Department and Columbia Astrophysics Laboratory, Columbia University, 538 West 120th Street, New York, NY 10027 (United States)

    2013-09-10

    Magnetar magnetospheres are believed to be strongly twisted due to shearing of the stellar crust by internal magnetic stresses. We present time-dependent axisymmetric simulations showing in detail the evolution of relativistic force-free magnetospheres subjected to slow twisting through large angles. When the twist amplitude is small, the magnetosphere moves quasi-statically through a sequence of equilibria of increasing free energy. At some twist amplitude the magnetosphere becomes tearing-mode unstable to forming a resistive current sheet, initiating large-scale magnetic reconnection in which a significant fraction of the magnetic free energy can be dissipated. This ''critical'' twist angle is insensitive to the resistive length scale. Rapid shearing temporarily stabilizes the magnetosphere beyond the critical angle, allowing the magnetosphere of a rapidly differentially rotating star to store and dissipate more free energy. In addition to these effects, shearing the surface of a rotating star increases the spindown torque applied to the star. If shearing is much slower than rotation, the resulting spikes in spindown rate can occur on timescales anywhere from the long twisting timescale to the stellar spin period or shorter, depending both on the stellar shear distribution and the existing distribution of magnetospheric twists. A model in which energy is stored in the magnetosphere and released by a magnetospheric instability therefore predicts large changes in the measured spindown rate before soft gamma repeater giant flares.

  14. Incremental Topological Ordering and Strong Component Maintenance

    CERN Document Server

    Haeupler, Bernhard; Tarjan, Robert E

    2008-01-01

    We present an on-line algorithm for maintaining a topological order of a directed acyclic graph as arcs are added, and detecting a cycle when one is created. Our algorithm takes O(m^{1/2}) amortized time per arc, where m is the total number of arcs. For sparse graphs, this bound improves the best previous bound by a logarithmic factor and is tight to within a constant factor for a natural class of algorithms that includes all the existing ones. Our main insight is that the bidirectional search method of previous algorithms does not require an ordered search, but can be more general. This allows us to avoid the use of heaps (priority queues) entirely. Instead, the deterministic version of our algorithm uses (approximate) median-finding. The randomized version of our algorithm avoids this complication, making it very simple. We extend our topological ordering algorithm to give the first detailed algorithm for maintaining the strong components of a directed graph, and a topological order of these components, as ...

  15. Strong Coulomb Coupling in the Todorov Equation

    Science.gov (United States)

    Bawin, M.; Cugnon, J.; Sazdjian, H.

    A positronium-like system with strong Coulomb coupling, considered in its pseudoscalar sector, is studied in the framework of relativistic quantum constraint dynamics with the Todorov choice for the potential. Case’s method of self-adjoint extension of singular potentials, which avoids explicit introduction of regularization cut-offs, is adopted. It is found that, as the coupling constant α increases, the bound state spectrum undergoes an abrupt change at the critical value α=αc=1/2. For α>αc, the mass spectrum displays, in addition to the existing states for α<αc, a new set of an infinite number of bound states concentrated in a narrow band starting at mass W=0; all the states have indefinitely oscillating wave functions near the origin. In the limit α→αc from above, the oscillations disappear and the narrow band of low-lying states shrinks to a single massless state with a mass gap with the rest of the spectrum. This state has the required properties to represent a Goldstone boson and to signal spontaneous breakdown of chiral symmetry.

  16. Simulating strongly coupled plasmas at low temperatures

    Science.gov (United States)

    Bussmann, M.; Schramm, U.; Habs, D.

    2006-10-01

    Realistic molecular dynamics (MD) simulations of the particle dynamics in strongly coupled plasmas require the computation of the mutual Coulomb-force for each pair of charged particles if a correct treatment of long range correlations is required. For plasmas with N > 104 particles this requires a tremendous number of computational steps which can only be addressed using efficient parallel algorithms adopted to modern super-computers. We present a new versatile MD simulation code which can simulate the non-relativistic mutual Coulomb-interaction of a large number of charged particles in arbitrary external field configurations. A demanding application is the simulation of the complete dynamics of in-trap stopping of highly charged ions in a laser cooled plasma of N = 105 24Mg+ ions. We demonstrate that the simulation is capable of delivering results on stopping times and plasma dynamics under realistic conditions. The results suggest that this stopping scheme can compete with in-trap electron cooling and might be an alternative approach for delivering ultra cold highly charged ions for future trap-based experiments aiming for precision mass measurements of stable and radioactive nuclei.

  17. Emergent behavior in strongly correlated electron systems

    Science.gov (United States)

    Pines, David

    2016-09-01

    I describe early work on strongly correlated electron systems (SCES) from the perspective of a theoretical physicist who, while a participant in their reductionist top-down beginnings, is now part of the paradigm change to a bottom-up ‘emergent’ approach with its focus on using phenomenology to find the organizing principles responsible for their emergent behavior disclosed by experiment—and only then constructing microscopic models that incorporate these. After considering the organizing principles responsible for the emergence of plasmons, quasiparticles, and conventional superconductivity in SCES, I consider their application to three of SCES’s sister systems, the helium liquids, nuclei, and the nuclear matter found in neutron stars. I note some recent applications of the random phase approximation and examine briefly the role that paradigm change is playing in two central problems in our field: understanding the emergence and subsequent behavior of heavy electrons in Kondo lattice materials; and finding the mechanism for the unconventional superconductivity found in heavy electron, organic, cuprate, and iron-based materials.

  18. Binary Polymer Brushes of Strongly Immiscible Polymers.

    Science.gov (United States)

    Chu, Elza; Babar, Tashnia; Bruist, Michael F; Sidorenko, Alexander

    2015-06-17

    The phenomenon of microphase separation is an example of self-assembly in soft matter and has been observed in block copolymers (BCPs) and similar materials (i.e., supramolecular assemblies (SMAs) and homo/block copolymer blends (HBCs)). In this study, we use microphase separation to construct responsive polymer brushes that collapse to generate periodic surfaces. This is achieved by a chemical reaction between the minor block (10%, poly(4-vinylpyridine)) of the block copolymer and a substrate. The major block of polystyrene (PS) forms mosaic-like arrays of grafted patches that are 10-20 nm in size. Depending on the nature of the assembly (SMA, HBC, or neat BCP) and annealing method (exposure to vapors of different solvents or heating above the glass transition temperature), a range of "mosaic" brushes with different parameters can be obtained. Successive grafting of a secondary polymer (polyacrylamide, PAAm) results in the fabrication of binary polymer brushes (BPBs). Upon being exposed to specific selective solvents, BPBs may adopt different conformations. The surface tension and adhesion of the binary brush are governed by the polymer occupying the top stratum. The "mosaic" brush approach allows for a combination of strongly immiscible polymers in one brush. This facilitates substantial contrast in the surface properties upon switching, previously only possible for substrates composed of predetermined nanostructures. We also demonstrate a possible application of such PS/PAAm brushes in a tunable bioadhesion-bioadhesive (PS on top) or nonbioadhesive (PAAm on top) surface as revealed by Escherichia coli bacterial seeding.

  19. Chirally symmetric strong and electroweak interactions

    Energy Technology Data Exchange (ETDEWEB)

    Rajpoot, S.

    1988-07-21

    Strong and electroweak interactions may be a relic of the spontaneous breakdown of a chirally symmetric colour-flavour gauge group. The minimum possibility of such a structure that is symmetric between left and right is SU(3)/sub L/xSU(3)/sub R/xSU(2)/sub L/xSU(2)/sub R/xU(1)/sub B-L/ where quantum chromodynamics originates in the chiral colour group SU(3)/sub L/xSU(3)/sub R/ and the electroweak interaction originates in the ambidextrous electroweak interaction group SU(2)/sub L/xSU(2)/sub R/xU(1)/sub B-L/. The chiral anomalies are cancelled by adding a set of fermions that transform as singlets under the weak interaction group SU(2)/sub L/xSU(2)/sub R/. This model requires only three Higgs representations to break the proposed gauge symmetry to SU(3)/sup C/xU(1)/sub em/ and give masses to all the quarks and leptons of the theory. All fermion masses are 'see-saw' masses.

  20. Strong reinforcing selection in a Texas wildflower.

    Science.gov (United States)

    Hopkins, Robin; Guerrero, Rafael F; Rausher, Mark D; Kirkpatrick, Mark

    2014-09-08

    Reinforcement, the process of increased reproductive isolation due to selection against hybrids, is an important mechanism by which natural selection contributes to speciation [1]. Empirical studies suggest that reinforcement has generated reproductive isolation in many taxa (reviewed in [2-4]), and theoretical work shows it can act under broad selective conditions [5-11]. However, the strength of selection driving reinforcement has never been measured in nature. Here, we quantify the strength of reinforcing selection in the Texas wildflower Phlox drummondii using a strategy that weds a population genetic model with field data. Reinforcement in this system is caused by variation in two loci that affect flower color [12]. We quantify sharp clines in flower color where this species comes into contact with its congener, Phlox cuspidata. We develop a spatially explicit population genetic model for these clines based on the known genetics of flower color. We fit our model to the data using likelihood, and we searched parameter space using Markov chain Monte Carlo methods. We find that selection on flower color genes generated by reinforcement is exceptionally strong. Our findings demonstrate that natural selection can play a decisive role in the evolution of reproductive isolation through the process of reinforcement.