Study of neutron-induced background and its effect on the search of 0νββ decay in¹²⁴Sn

Abstract

Neutron-induced background has been studied in various components of the TIN.TIN detector, which is under development for the search of Neutrinoless Double Beta Decay in 124 Sn. Fast neutron flux ∼ 10 6 n cm −2 s −1 covering a broad energy range (∼ 0.1 to ∼ 18 MeV) was generated using 9 Be(p, n) 9 B reaction. In addition, reactions with quasi-monoenergetic neutrons were also studied using 7 Li(p, n) 7 Be reaction. Among the different cryogenic support structures studied, Teflon is found to be preferable compared to Torlon as there is no high energy gamma background (E γ > 1 MeV). Contribution of neutron-induced reactions in nat,124 Sn from other Sn isotopes (A = 112 -122) in the energy region of interest, namely, around the Q β β of 124 Sn (E ∼ 2.293 MeV), is also investigated.

Estimation of low energy neutron flux (En⩽ 15 MeV) in India-based Neutrino Observatory cavern using Monte Carlo techniques

“…The neutron-induced background (E n ≤ 18 MeV) in the detector and surrounding materials has been studied using neutron activation techniques [8]. To evaluate the background levels induced by fast neutrons in the underground cavern and the necessary neutron shield requirements, it is essential to have an understanding of the neutron flux in the underground cavern.…”

“…In India, a Tin cryogenic bolometer (TIN.TIN) is under development to search for neutrinoless double beta decay (0νβ β ) in 124 Sn and is proposed to be installed at the upcoming India-based Neutrino Observatory (INO) [6,7]. The neutron-induced background (E n ≤ 18 MeV) in the detector and surrounding materials has been studied using neutron activation techniques [8]. To evaluate the background levels induced by fast neutrons in the underground cavern and the necessary neutron shield requirements, it is essential to have an understanding of the neutron flux in the underground cavern.…”

Required sensitivity in the search of neutrinoless double beta decay in 124Sn

“…Rare event physics search like 0νββ and dark matter naturally demands the very low background experiment [46]. The understanding of background and its suppression would significantly improves the experimental sensitivity.…”

Study of Radiation Background for TIN.TIN

“…The understanding of the neutron flux in the underground cavern is important to evaluate the background levels and the shield requirements. The neutrons originating from the radioactivity of underground rock can lead to neutron and gamma background in the T IN.T IN detector [6]. The ICPMS (Inductively Coupled Plasma Mass Spectrometry) analysis of the INO cavern rock indicated 60 ppb of 238 U and 224 ppb of 232 Th in the rock.…”