7,262 research outputs found

    Polarized quark distributions in nuclear matter

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    We compute the polarized quark distribution function of a bound nucleon. The Chiral Quark-Soliton model provides the quark and antiquark substructure of the nucleon embedded in nuclear matter. Nuclear effects cause significant modifications to the polarized distributions including an enhancement of the axial coupling constant.Comment: 5 Pages, 2 Postscript figures, Version to be published in Phys. Rev.

    The effect of protons on the performance of swept-charge devices

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    This is the pre-print version of the final paper published in Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2009 Elsevier B.V.The e2v technologies CCD54, or swept-charge device (SCD) has been extensively radiation tested for use in the Chandrayaan-1 X-ray Spectrometer (C1XS) instrument, to be launched as a part of the Indian Space Research Organisation (ISRO) Chandrayaan-1 payload in 2008. The principle use of the SCD is in X-ray fluorescence (XRF) applications, the device providing a relatively large collecting area of 1.1 cm2, and achieving near Fano-limited spectroscopy at −15 °C, a temperature that is easily obtained using a thermoelectric cooler (TEC). This paper describes the structure and operation of the SCD and details the methodology and results obtained from two proton irradiation studies carried out in 2006 and 2008, respectively to quantify the effects of proton irradiation on the operational characteristics of the device. The analysis concentrates on the degradation of the measured FWHM of various elemental lines and quantifies the effects of proton fluence on the observed X-ray fluorescence spectra from mineralogical target samples

    Chiral solitons in nuclei: Electromagnetic form factors

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    We calculate the electromagnetic form factors of a bound proton. The Chiral Quark-Soliton model provides the quark and antiquark substructure of the proton, which is embedded in nuclear matter. This procedure yields significant modifications of the form factors in the nuclear environment. The sea quarks are almost completely unaffected, and serve to mitigate the valence quark effect. In particular, the ratio of the isoscalar electric to the isovector magnetic form factor decreases by 20% at Q^2=1 GeV^2 at nuclear density, and we do not see a strong enhancement of the magnetic moment.Comment: 13 pages, 6 figures, Added references and a clearer connection to experimen

    Invested With a Strange Authority: A Guide to the Insanity Defense and Related Issues in Tennessee

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    Part I of this article will examine the current state of the insanity defense in Tennessee and the most common issues that arise when it is litigated. Part II of this article will provide a general overview of the present version of the insanity defense, looking at its background, the procedural prerequisites for raising it, and its elements. Part III will examine the burden of proof for the insanity defense. Part IV will discuss the scope of expert testimony with respect to the insanity defense. Part V will examine what happens after the insanity defense has been litigated at trial, looking at the appellate standard of review and the procedure upon a verdict of not guilty by reason of insanity. Part VI will briefly examine some issues related to the insanity defense such as “diminished capacity,” sentencing, and post-conviction claims

    Poster 254 Outcomes of Acute Inpatient Rehabilitation for Chronic Graft‐Versus‐Host‐Disease (cGVHD)

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/147174/1/pmr2s174b.pd

    Coupling starlight into single-mode photonic crystal fiber using a field lens.

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    We determine the coupling characteristics of a large mode area (LMA) photonic crystal, single-mode fiber when fed with an on-axis field lens used to place an image of the telescope exit pupil at the fiber input. The maximum field of view is found to be approximately the same as that of feeding the fiber directly with the telescope PSF in the image plane. However, the field lens feed can be used to provide a flat, maximised coupling response over the entire visible-NIR which is not possible using either the highly wavelength dependent direct feed coupling to the LMA fiber or the attenuation spectrum limited step index fiber cases

    Light Dark Matter Detection Prospects at Neutrino Experiments

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    We consider the prospects for the detection of relatively light dark matter through direct annihilation to neutrinos. We specifically focus on the detection possibilities of water Cherenkov and liquid scintillator neutrino detection devices. We find in particular that liquid scintillator detectors may potentially provide excellent detection prospects for dark matter in the 4-10 GeV mass range. These experiments can provide excellent corroborative checks of the DAMA/LIBRA annual modulation signal, but may yield results for low mass dark matter in any case. We identify important tests of the ratio of electron to muon neutrino events (and neutrino versus anti-neutrino events), which discriminate against background atmospheric neutrinos. In addition, the fraction of events which arise from muon neutrinos or anti-neutrinos (RμR_{\mu} and RμˉR_{\bar \mu}) can potentially yield information about the branching fractions of hypothetical dark matter annihilations into different neutrino flavors. These results apply to neutrinos from secondary and tertiary decays as well, but will suffer from decreased detectability.Comment: 13 pages, 2 figures, pdflatex, references, one figure and comments on electron neutrino bounds and on spin-dependent scattering limits added. Figures updated

    Dark Matter Detection With Electron Neutrinos in Liquid Scintillation Detectors

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    We consider the prospects for liquid scintillation experiments (with a focus on KamLAND) to detect the flux of electron neutrinos arising from dark matter annihilation in the core of the sun. We show that, with data already taken, KamLAND can provide the greatest sensitivity to the dark matter-proton spin-dependent scattering cross-section for dark matter lighter than 20 GeV. It is also possible to probe the dark matter-nucleon spin-independent scattering cross-section for isospin-violating dark matter lighter than 10 GeV. KamLAND can thus potentially confirm the dark matter interpretation of the DAMA and CoGeNT signals, utilizing data already taken.Comment: 5 pages, 4 figures, PDFLaTeX; v2: references added, figures updated, more detailed comparison of liquid scintillation and water Cerenkov detectors (journal version
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