arXiv subjects

V. L. Matushko

Publications and source records attributed to V. L. Matushko.

3 recordsLinked to original sources

arXiv2016

Response of a proportional counter to $^{37}$Ar and $^{71}$Ge: measured spectra versus Geant4 simulation

The energy deposition spectra of $^{37}$Ar and $^{71}$Ge in a miniature proportional counter are measured and compared in detail to the model response simulated with Geant4. A certain modification of the Geant4 code, making it possible to trace the deexcitation of atomic shells properly, is suggested. Modified Geant4 is able to reproduce a response of particle detectors in detail in the keV energy range. This feature is very important for the laboratory experiments that search for massive sterile neutrinos as well as for dark matter searches that employ direct detection of recoil nuclei. This work demonstrates the reliability of Geant4 simulation at low energies.

physics.ins-det↗

arXiv2015

The TOF method for the LSDS-100 spectrometer

The first lead neutron slowing-down spectrometer (LSDS) from a pulsed source in elastic scattering on lead nuclei has been constructed in the laboratory of the atomic nucleus of the Physics Institute of the Russian Academy of Sciences LPI. Currently, there are several operating lead neutron slowing-down spectrometers: LSDS-100 in Russia, RINS in United States, KULS in Japan and others. A relation between an energy of lead slowing-down moderated neutrons E (eV) and the time delay of t (μs) is described by the expression: E(t) = K/(t + t_0)^2, where values of K=170.5 (keV μs^2), t_0 = 0.3 (μs) in the case of the LSDS-100 have been measured in the previous experiment. The energy resolution of LSDS is low (30-45%) and is being determined experimentally, but the aperture ratio luminosity of the neutron flux detector is 10^2-10^4 times greater than in the case of a time of flight method technique. It allows to make experiments with small amount of substance and small cross-sections of its interaction with the slowed moderated neutrons.

physics.ins-det↗

arXiv2006

Measurement of Neutron Background at the Pyhasalmi mine for CUPP Project, Finland

A natural neutron flux is one of significant kind of background in high-sensitive underground experiments. Therefore, when scheduling a delicate underground measurements one needs to measure neutron background. Deep underground the most significant source of neutrons are the U-Th natural radioactive chains giving a fission spectrum with the temperature of 2-3 MeV. Another source is the U-Th alpha-reactions on light nuclei of mine rock giving neutrons with different spectra in the 1-15 MeV energy region. Normal basalt mine rocks contain 1 ppm g/g of U-238 and less. Deep underground those rocks produce natural neutron fluxes of 10^{-7} - 10^{-6} cm^{-2}s^{-1} above 1 MeV. To measure such a background one needs a special techniques. In the Institute for Nuclear Research, Moscow, the neutron spectrometer was developed and built which is sensitive to such a low neutron fluxes. At the end of 2001 the collection of neutron data at the Pyhasalmi mine was started for the CUPP project. During 2002 the background and rough energy spectra of neutron at underground levels 410, 660, 990 and 1410 m were measured. The result of the measurement of the neutron background at different levels of the Pyhasalmi mine is presented and discussed. Data analysis is performed in different energy ranges from thermal neutrons up to 25 MeV and above.

nucl-ex↗