Showing papers by "V. A. Belov published in 2012"
TL;DR: In this article, the authors report experimental upper limits on WIMP-nucleon elastic scattering cross sections from the second science run of ZEPLIN-III at the Boulby Underground Laboratory.
178 citations
TL;DR: In this article, the relative scintillation efficiency for low-energy nuclear recoils in a polystyrene-based plastic scintillator (UPS-923A) is presented, exploring recoil energies between 125 and 850 keV.
Abstract: Plastic scintillators are widely used in industry, medicine, and scientific research, including nuclear and particle physics. Although one of their most common applications is in neutron detection, experimental data on their response to low-energy nuclear recoils are scarce. Here, the relative scintillation efficiency for neutron-induced nuclear recoils in a polystyrene-based plastic scintillator (UPS-923A) is presented, exploring recoil energies between 125 and 850 keV. Monte Carlo simulations, incorporating light collection efficiency and energy resolution effects, are used to generate neutron scattering spectra which are matched to observed distributions of scintillation signals to parameterize the energy-dependent quenching factor. At energies above 300 keV the dependence is reasonably described using the semiempirical formulation of Birks and a kB factor of (0.014±0.002) g MeV -1 cm -2 has been determined. Below that energy, the measured quenching factor falls more steeply than predicted by the Birks formalism. © 2012 American Physical Society.
28 citations
TL;DR: In this article, electron and nuclear recoil background from radioactivity in the ZEPLIN-III dark matter experiment at Boulby was examined and the rate of low-energy electron recoils in the liquid xenon WIMP target is 0.75±0.05 events/kg/day/keV.
28 citations
TL;DR: In this article, the authors present the first results of studying the nature of single-electron noise in a liquid-xenon emission detector and consider possible ways to suppress it.
Abstract: A technique for studying single-electron noise in emission detectors that are intended for detection of rare processes with small energy releases is developed. Examples of possible applications are experiments for search of dark matter in the Universe and detection of reactor antineutrinos via coherent neutrino scattering at heavy xenon nuclei. We present the first results of studying the nature of single-electron noise in a liquid-xenon emission detector and consider possible ways to suppress it.
24 citations
11 Dec 2012-Nuclear Instruments & Methods in Physics Research Section A-accelerators Spectrometers Detectors and Associated Equipment
TL;DR: In this paper, a wavelength shifter was developed for the use with an array of blue-sensitive multipixel avalanche Geiger photodiodes (MRS APD) to detect Xe 175nm emission.
Abstract: Development study of a wavelength shifter (WLS) to convert a noble gas emission light from the VUV region to the visible range is presented. The shifter is developed for the use with an array of blue-sensitive multipixel avalanche Geiger photodiodes (MRS APD) to detect Xe 175 nm emission. It was found that a polycrystalline p-terphenyl having an absorption peak at 180 nm with a molar extinction coefficient e of 37500±5000 mol −1 ·l cm −1 is well suited for this. To satisfy a requirement of compatibility with an extra pure noble gas detection medium the p-terphenyl layer was coated with an ∼1 μm thick poly-para-xylylene protection film. A new WLS with maximum of emission spectrum at 390 nm and at 420 nm is developed on the basis of a nanostructured organosilicon luminophore.
22 citations
TL;DR: ZEPLIN-III as mentioned in this paper is a two-phase Xenon direct dark matter experiment located at the Boulby Mine (U.K.). After its first science run in 2008 it was upgraded with: an array of low background photomultipliers, a new anti-coincidence detector system with plastic scintillator and an improved calibration system.
Abstract: ZEPLIN-III is a two-phase xenon direct dark matter experiment located at the Boulby Mine (U.K.). After its first science run in 2008 it was upgraded with: an array of low background photomultipliers, a new anti-coincidence detector system with plastic scintillator and an improved calibration system. After 319 days of data taking the second science run ended in May 2011. In this paper we describe the instrument performance with emphasis on the position and energy reconstruction algorithm and summarise the final science results.
4 citations