320 research outputs found

    Zonal Modes of Cosmic Microwave Background Temperature Maps

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    All-sky maps of the cosmic microwave background temperature fluctuations are usually represented by a spherical harmonic decomposition involving modes labelled by their degree l and order m (where -l < m < +l). The zonal modes (i.e those with m = 0) are of particular interest because they vary only with galactic latitude; any anomalous behaviour in them might therefore be an indication of erroneous foreground substraction. We perform a simple statistical analysis of the modes with low l for sky maps derived via different cleaning procedures from the Wilkinson Microwave Anisotropy Probe (WMAP) and show that the zonal modes provide a useful diagnostic of possible systematics.Comment: 5 pages, 4 tables, 2 figures, accepted for publication in MNRA

    Models for the Clustering of Far-Infrared and Sub-millimetre selected Galaxies

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    We discuss and compare two alternative models for the two-point angular correlation function of galaxies detected through the sub-millimetre emission using the Herschel Space Observatory. The first, now-standard Halo Model, which represents the angular correlations as arising from one-halo and two-halo contributions, is flexible but complex and rather unwieldy. The second model is based on a much simpler approach: we incorporate a fitting function method to estimate the matter correlation function with approximate model of the bias inferred from the estimated redshift distribution to find the galaxy angular correlation function. We find that both models give a good account of the shape of the correlation functions obtained from published preliminary studies of the HerMES and H-ATLAS surveys performed using Herschel, and yield consistent estimates of the minimum halo mass within which the sub-millimetre galaxies must reside. We note also that both models predict an inflection in the correlation function at intermediate angular scales, so the presence of the feature in the measured correlation function does not unambiguously indicate the presence of intra-halo correlations. The primary barrier to more detailed interpretation of these clustering measurements lies in the substantial uncertainty surrounding the redshift distribution of the sources.Comment: 5 pages, 6 figures, 1 table, accepted for publication in MNRA

    Statistical Characterization of Temperature Patterns in Anisotropic Cosmologies

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    We consider the issue of characterizing the coherent large-scale patterns from CMB temperature maps in globally anisotropic cosmologies. The methods we investigate are reasonably general; the particular models we test them on are the homogeneous but anisotropic relativistic cosmologies described by the Bianchi classification. Although the temperature variations produced in these models are not stochastic, they give rise to a "non-Gaussian" distribution of temperature fluctuations over the sky that is a partial diagnostic of the model. We explore two methods for quantifying non-Gaussian and/or non-stationary fluctuation fields in order to see how they respond to the Bianchi models.We first investigate the behavior of phase correlations between the spherical harmonic modes of the maps. Then we examine the behavior of the multipole vectors of the temperature distribution which, though defined in harmonic space, can indicate the presence of a preferred direction in real space, i.e. on the 2-sphere. These methods give extremely clear signals of the presence of anisotropy when applied to the models we discuss, suggesting that they have some promise as diagnostics of the presence of global asymmetry in the Universe.Comment: 14 pages, 10 figures, 4 tables, accepted by MNRA

    Measurements of neutrino oscillation in appearance and disappearance channels by the T2K experiment with 6.6 x 10(20) protons on target

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    111 pages, 45 figures, submitted to Physical Review D. Minor revisions to text following referee comments111 pages, 45 figures, submitted to Physical Review D. Minor revisions to text following referee comments111 pages, 45 figures, submitted to Physical Review D. Minor revisions to text following referee commentsWe thank the J-PARC staff for superb accelerator performance and the CERN NA61/SHINE Collaboration for providing valuable particle production data. We acknowledge the support of MEXT, Japan; NSERC, NRC, and CFI, Canada; CEA and CNRS/IN2P3, France; DFG, Germany; INFN, Italy; National Science Centre (NCN), Poland; RSF, RFBR and MES, Russia; MINECO and ERDF funds, Spain; SNSF and SER, Switzerland; STFC, UK; and the U. S. Deparment of Energy, USA. We also thank CERN for the UA1/NOMAD magnet, DESY for the HERA-B magnet mover system, NII for SINET4, the WestGrid and SciNet consortia in Compute Canada, GridPP, UK, and the Emerald High Performance Computing facility in the Centre for Innovation, UK. In addition, participation of individual researchers and institutions has been further supported by funds from ERC (FP7), EU; JSPS, Japan; Royal Society, UK; and DOE Early Career program, USA

    Measurement of the electron neutrino charged-current interaction rate on water with the T2K ND280 pi(0) detector

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    10 pages, 6 figures, Submitted to PRDhttp://journals.aps.org/prd/abstract/10.1103/PhysRevD.91.112010© 2015 American Physical Society11 pages, 6 figures, as accepted to PRD11 pages, 6 figures, as accepted to PRD11 pages, 6 figures, as accepted to PR

    Search for short baseline nu(e) disappearance with the T2K near detector

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    8 pages, 6 figures, submitted to PRD rapid communication8 pages, 6 figures, submitted to PRD rapid communicationWe thank the J-PARC staff for superb accelerator performance and the CERN NA61 collaboration for providing valuable particle production data. We acknowledge the support of MEXT, Japan; NSERC, NRC and CFI, Canada; Commissariat `a l’Energie Atomique and Centre National de la Recherche Scientifique–Institut National de Physique Nucle´aire et de Physique des Particules, France; DFG, Germany; INFN, Italy; National Science Centre (NCN), Poland; Russian Science Foundation, RFBR and Ministry of Education and Science, Russia; MINECO and European Regional Development Fund, Spain; Swiss National Science Foundation and State Secretariat for Education, Research and Innovation, Switzerland; STFC, UK; and DOE, USA. We also thank CERN for the UA1/NOMAD magnet, DESY for the HERA-B magnet mover system, NII for SINET4, the WestGrid and SciNet consortia in Compute Canada, GridPP, UK. In addition participation of individual researchers and institutions has been further supported by funds from ERC (FP7), EU; JSPS, Japan; Royal Society, UK; DOE Early Career program, USA

    Genital tract abnormalities among female sex workers who douche with Lemon/Lime juice in Nigeria

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    Vaginal douche products have been associated with cervical cancer. We examined female sex workers (FSWs) in Nigeria who douche with lemon or lime juice and compared the findings with that of nonusers. We obtained Pap smears and performed colposcopy of the vulva, vagina and cervix. A total of 374 FSWs comprising 81 Lemon users (LUs) and 293 non lemon users (NLUs) were examined. Their mean age was 27.8 ± 6.7 (range 16-63) years. At colposcopy, 17(4.5%) had genital warts [LUs 5(6.2%); NLUs 12(4.1%); p=0.43], 61(16.3%) had suspectedsquamous intraepithelial lesions (SILs) [LUs 17(21.0%); NLUs 44(15.0%); p=0.20] and 65(17.4%) had other findings. Pap smear cytology showed that 87(24.6%) had SILs [LUs 26(33.3%); NLUs 61(22.1%); p=0.03]. Lemon/lime use was associated with cervical dysplasia after controlling for HIV status (Adjusted OR=1.8; 95% CI,1.0-3.0). Our data suggests an association between the practice of douching with citrus juice and cervical dysplasia (Afr J Reprod Health 2009; 13[1]:37-45)

    Measurement of coherent pi(+) production in low energy neutrino-carbon scattering

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    We report the first measurement of the flux-averaged cross section for charged current coherent π + production on carbon for neutrino energies less than 1.5 GeV, and with a restriction on the final state phase space volume in the T2K near detector, ND280. Comparisons are made with predictions from the Rein-Sehgal coherent production model and the model by Alvarez-Ruso et al., the latter representing the first implementation of an instance of the new class of microscopic coherent models in a neutrino interaction Monte Carlo event generator. We observe a clear event excess above background, disagreeing with the null results reported by K2K and SciBooNE in a similar neutrino energy region. The measured flux-averaged cross sections are below those predicted by both the Rein-Sehgal and Alvarez-Ruso et al. models

    Sensitivity of the T2K accelerator-based neutrino experiment with an Extended run to 20×102120\times10^{21} POT

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    18 pages, 4 figures18 pages, 4 figures18 pages, 4 figures18 pages, 4 figures18 pages, 4 figuresRecent measurements at the T2K experiment indicate that CP violation in neutrino mixing may be observed in the future by long-baseline neutrino oscillation experiments. We explore the physics program of an extension to the currently approved T2K running of 7.8×10217.8\times 10^{21} protons-on-target to 20×102120\times 10^{21} protons-on-target,aiming at initial observation of CP violation with 3σ\,\sigma or higher significance for the case of maximum CP violation. With accelerator and beam line upgrades, as well as analysis improvements, this program would occur before the next generation of long-baseline neutrino oscillation experiments that are expected to start operation in 2026.We acknowledge the support of MEXT, Japan; NSERC (Grant No. SAPPJ-2014-00031), NRC and CFI, Canada; CEA and CNRS/IN2P3, France; DFG, Germany; INFN, Italy; National Science Centre (NCN), Poland; RSF, RFBR and MES, Russia; MINECO and ERDF funds, Spain; SNSF and SERI, Switzerland; STFC, UK; and DOE, USA. We also thank CERN for the UA1/NOMAD magnet, DESY for the HERA-B magnet mover system, NII for SINET4, the WestGrid and SciNet consortia in Compute Canada, and GridPP in the United Kingdom. In addition, participation of individual researchers and institutions has been further supported by funds from ERC (FP7), H2020 Grant No. RISE-GA644294-JENNIFER, EU; JSPS, Japan; Royal Society, UK; and the DOE Early Career program, USA. CNRS/IN2P3: Centre National de la Recherche ScientifiqueInstitut National de Physique Nucleaire et de Physique des Particules RSF: Russian Science Foundation MES: Ministry of Education and Science, Russia ERDF: European Regional Development Fund SNSF: Swiss National Science Foundation SER (should be SERI): State Secretariat for Education, Research and Innovatio
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