论文标题
从$^6 $ lif瓷砖作为中子decay检测器的内壁的$γ$射线的测量
Measurement of $γ$ rays from $^6$LiF tile as an inner wall of a neutron-decay detector
论文作者
论文摘要
在日本质子加速器研究复合物（J-PARC）进行的中子寿命测量正在计算中子衰减的电子数量，其中时间投影室（TPC）。 TPC中生产的$γ$射线会导致不可还原的背景事件。为了实现确切的测量，TPC的内壁由$^6 $ li-en-endriched锂氟化锂（$^6 $ lif）瓷砖组成，以抑制$γ$射线的量。为了估算$^{6} {\ rm lif} $瓷砖的$γ$射线的量，使用也使用也使用也会进行驻仪馆探测器。我们使用带有剥离方法的蒙特卡洛模拟重建了测得的$γ$ -Ray能量谱。将测量频谱与模拟的频谱进行比较，从$^{6} {\ rm lif} $ tile发出的$γ$射线数为$（2.3^{+0.7} _ { - 0.3}）\ times 10^{ - 4} $ a Cher Act natermon Neutmon Neutron。这是$ 1.4^{+0.5} _ { - 0.2} $乘以$^{6} {\ rm lif} $ tile的摩尔分数所假定值的值。我们得出的结论是，从$^{6} {\ rm lif} $ tile产生的$γ$射线的量不是最初假定的值的两倍。
A neutron lifetime measurement conducted at the Japan Proton Accelerator Research Complex (J-PARC) is counting the number of electrons from neutron decays with a time projection chamber (TPC). The $γ$ rays produced in the TPC cause irreducible background events. To achieve the precise measurement, the inner walls of the TPC consist of $^6$Li-enriched lithium-fluoride ($^6$LiF) tiles to suppress the amount of $γ$ rays. In order to estimate the amount of $γ$ rays from the $^{6}{\rm LiF}$ tile, prompt gamma ray analysis (PGA) measurements were performed using germanium detectors. We reconstructed the measured $γ$-ray energy spectrum using a Monte Carlo simulation with the stripping method. Comparing the measured spectrum with a simulated one, the number of $γ$ rays emitted from the$^{6}{\rm LiF}$ tile was $(2.3^{+0.7}_{-0.3}) \times 10^{-4}$ per incident neutron. This is $1.4^{+0.5}_{-0.2}$ times the value assumed for a mole fraction of the $^{6}{\rm LiF}$ tile. We concluded that the amount of $γ$ rays produced from the $^{6}{\rm LiF}$ tile is not more twice the originally assumed value.
