Nuleárny seminár - Róbert Breier (6.12.2017)
v stredu 6.12.2017 o 14:00 hod. v miestnosti F1/364
Od: Jaroslav Staníček
Pozývame Vás na Nukleárny seminár Katedry jadrovej fyziky a biofyziky FMFI UK, Slovenskej fyzikálnej spoločnosti a Slovenskej nukleárnej spoločnosti.
Prednášajúci: Mgr. Róbert Breier, PhD.
Názov: Monte Carlo simulations of background of HPGe spectrometers operating underground
Termín: 6.12.2017, 14:00 hod., zasadačka KJFB (F1/364)
An increasing number of experiments have been devoted to the detection of very rare events, e.g. in double beta-decay, dark matter and neutrino experiments, as well as in environmental physics. Their common feature is utilization of high-sensitive gamma-spectrometers, operating very often underground. If a detector was constructed from selected radioactivity free materials, the dominating background component in a surface or shallow underground laboratory would be cosmic rays. The flux of soft component cosmic-ray particles (electrons, positrons, gamma-rays) can be considerably decreased due to electromagnetic showers in materials with high atomic number, e.g. lead, iron, and copper, etc. On the other hand, the flux of hard component particles (muons) can be decreased only by installation of detectors deep underground, or partially by using an anticosmic shielding. The Monte Carlo simulated cosmic-ray background gamma-ray spectrum has been by about three orders of magnitude lower than the experimental spectrum measured in the LSM underground laboratory in Modane (4800 m w.e.), underlying the importance of radiopure materials for the construction of ultra-low-level Ge gamma-ray spectrometers. Similar results have been found for Ge detector operating in the Gran Sasso underground laboratory.