17 research outputs found

    The Electronics and Data Acquisition System of the DarkSide Dark Matter Search

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    It is generally inferred from astronomical measurements that Dark Matter (DM) comprises approximately 27\% of the energy-density of the universe. If DM is a subatomic particle, a possible candidate is a Weakly Interacting Massive Particle (WIMP), and the DarkSide-50 (DS) experiment is a direct search for evidence of WIMP-nuclear collisions. DS is located underground at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy, and consists of three active, embedded components; an outer water veto (CTF), a liquid scintillator veto (LSV), and a liquid argon (LAr) time projection chamber (TPC). This paper describes the data acquisition and electronic systems of the DS detectors, designed to detect the residual ionization from such collisions

    Could the Quick Inventory of Depressive Symptomatology-Self-Report (QIDS-SR) be used in depressed schizophrenia patients?

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    BACKGROUND: Developing accurate and time-efficient tools to measure depressive symptoms in schizophrenia is important for research and clinical practice. This study tested the psychometric properties of the Chinese version of the 16-item Quick Inventory of Depressive Symptomatology (QIDS-SR) in depressed schizophrenia patients. METHODS: This study included 337 clinically stable patients with schizophrenia. The severity of depressive symptoms was assessed using the Montgomery-Asberg Depression Rating Scale (MADRS), QIDS-SR at baseline and 2 weeks later. Negative symptoms and extrapyramidal symptoms were measured with the negative symptom score of Brief Psychiatric Rating Scale (BPRS) and the Simpson-Angus Scale of Extrapyramidal Symptoms (SAS), respectively. RESULTS: Internal consistency (Cronbachs alpha) was 0.73 and 0.67 for QIDS-SR at the baseline and endpoint, respectively. The intra-class correlation coefficient (ICC) for test-retest reliability over the two weeks was 0.77. Two domains (involvement and energy) at baseline and one domain (energy) at endpoint had the highest item-total correlations. The QIDS-SR total score was significantly correlated with the MADRS total score at baseline (r=0.44,

    Could the Quick Inventory of Depressive Symptomatology-Self-Report (QIDS-SR) be used in depressed schizophrenia patients?

    No full text
    Background: Developing accurate and time-efficient tools to measure depressive symptoms in schizophrenia is important for research and clinical practice. This study tested the psychometric properties of the Chinese version of the 16-item Quick Inventory of Depressive Symptomatology (QIDS-SR) in depressed schizophrenia patients. Methods: This study included 337 clinically stable patients with schizophrenia. The severity of depressive symptoms was assessed using the Montgomery-Asberg Depression Rating Scale (MADRS), QIDS-SR at baseline and 2 weeks later. Negative symptoms and extrapyramidal symptoms were measured with the negative symptom score of Brief Psychiatric Rating Scale (BPRS) and the SimpsonAngus Scale of Extrapyramidal Symptoms (SAS), respectively. Results: Internal consistency (Cronbach\u27s alpha) was 0.73 and 0.67 for QIDS-SR at the baseline and endpoint, respectively. The intra-class correlation coefficient (ICC) for test-retest reliability over the two weeks was 0.77. Two domains (involvement and energy) at baseline and one domain (energy) at endpoint had the highest item-total correlations. The QIDS-SR total score was significantly correlated with the MADRS total score at baseline (r=0.44,

    DarkSide-50, a background free experiment for dark matter searches

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    The existence of dark matter is inferred from gravitational effects, but its nature remains a deep mystery. One possibility, motivated by considerations in elementary particle physics, is that dark matter consists of elementary particles, such as the hypothesized Weakly Interacting Massive Particles (WIMPs), with mass ~ 100 GeV and cross-section ~ 10−47 cm2, that can be gravitationally trapped inside our galaxy and revealed by their scattering on nuclei. It should be possible to detect WIMPs directly, as the orbital motion of the WIMPs composing the dark matter halo pervading the galaxy should result in WIMP-nucleus collisions of sufficient energy to be observable in the laboratory. The DarkSide-50 experiment is a direct WIMP search using a Liquid Argon Time Projection Chamber (LAr-TPC) with an active mass of 50 kg with a high sensitivity and an ultra-low background detector

    The Electronics and Data Acquisition System of the DarkSide Dark Matter Search

    No full text
    It is generally inferred from astronomical measurements th at Dark Matter (DM) comprises approximately 27% of the energy-dens ity of the universe. If DM is a subatomic particle, a possible candidate is a Weakl y Interacting Mas- sive Particle (WIMP), and the DarkSide-50 (DS) experiment i s a direct search for evidence of WIMP-nuclear collisions. DS is located undergr ound at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy, and consists of thr ee active, embedded components; an outer water veto (CTF), a liquid scintillato r veto (LSV), and a liquid argon (LAr) time projection chamber (TPC). This pap er describes the data acquisition and electronic systems of the DS detectors , designed to detect the residual ionization from

    First Results from the DarkSide-50 Dark Matter Experiment at Laboratori Nazionali del Gran Sasso

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    We report the first results of DarkSide-50, a direct search for dark matter operating in the un- derground Laboratori Nazionali del Gran Sasso (LNGS) and searching for the rare nuclear recoils possibly induced by weakly interacting massive particles (WIMPs). The dark matter detector is a Liquid Argon Time Projection Chamber with a ( 46.4 0.7 ) kg active mass, operated inside a 30 t or- ganic liquid scintillator neutron veto, which is in turn installed at the center of a 1 kt water Cherenkov veto for the residual flux of cosmic rays. We report here the null results of a dark matter search for a ( 1422 67 ) kg d exposure with an atmospheric argon fill. This is the most sensitive dark matter search performed with an argon target, corresponding to a 90% CL upper limit on the WIMP-nucleon spin-independent cross section of 6.1 1

    Two- and three-pion quantum statistics correlations in Pb-Pb collisions at 1asNN = 2.76 TeV at the CERN Large Hadron Collider

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    Correlations induced by quantum statistics are sensitive to the spatiotemporal extent as well as dynamics of particle-emitting sources in heavy-ion collisions. In addition, such correlations can be used to search for the presence of a coherent component of pion production. Two- and three-pion correlations of same and mixed charge are measured at low relative momentum to estimate the coherent fraction of charged pions in Pb-Pb collisions at 1asNN = 2.76 TeV at the CERN Large Hadron Collider with ALICE. The genuine three-pion quantum statistics correlation is found to be suppressed relative to the two-pion correlation based on the assumption of fully chaotic pion emission. The suppression is observed to decrease with triplet momentum. The observed suppression at low triplet momentum may correspond to a coherent fraction in charged-pion emission of 23% \ub1 8%
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