Qianming Wang , Zeyu Huang , Pengchong Hu , Emilio Ciuffoli
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引用次数: 0
Abstract
An extremely low-background environment is a crucial requirement for any neutrinoless double beta decay experiment. Neutrons are very difficult to stop, because they can pass through the shielding and activate nuclei in the detector, even inside the fiducial volume itself. Using Geant4 simulations we have studied the neutron background for NDEx-100 and the most efficient way to reduce it. Using a 60 cm thick external high-density polyethylene (HDPE) shielding the neutron background can be reduced down to events/year, lower than the background rate due to natural radioactivity (0.42 events/year), which was used as a benchmark for these calculations. The amount of HDPE needed can be significantly reduced by placing a filler in the empty space between the lead shielding and the steel vessel; in this way, it is sufficient to add 20 cm external HDPE shielding to reduce the neutron background down to events/year.
期刊介绍:
Astroparticle Physics publishes experimental and theoretical research papers in the interacting fields of Cosmic Ray Physics, Astronomy and Astrophysics, Cosmology and Particle Physics focusing on new developments in the following areas: High-energy cosmic-ray physics and astrophysics; Particle cosmology; Particle astrophysics; Related astrophysics: supernova, AGN, cosmic abundances, dark matter etc.; Gravitational waves; High-energy, VHE and UHE gamma-ray astronomy; High- and low-energy neutrino astronomy; Instrumentation and detector developments related to the above-mentioned fields.