Speaker
tianyu liang
Description
N$\nu$DEx experiment aims to search for the 0νββ of $\mathrm{^{82}Se}$ using high pressure $\mathrm{^{82}SeF_6}$ gas TPC. Accurate track simulation and reconstruction is essential for the study of background rejection and signal identification. In this work, we present a simulation framework and preliminary study of the signal and background discrimination for the N$\nu$DEx experiment, which includes:
- Calculation of reduced mobilities of $\mathrm{SeF_{5}^{-}}$ and $\mathrm{SeF_{6}^{-}}$ in $\mathrm{SeF_{6}}$. The reduced mobility for $\mathrm{SeF_{5}^{-}}$ and $\mathrm{SeF_{6}^{-}}$ in $\mathrm{SeF_{6}}$ are calculated using Avogardo, Gaussian16 and IMoS softwares based on the Mason-Schamp equation.
- TPC geometry with 10k sensors readout array. Both the weighting and electric fields of the TPC are constructed in COMSOL Multiphysics.
- Simulation of signal and background events in the gas using Geant4.
- Transportation of charge carriers in the gas. The Garfield++ is used for the charge transportation in the gas and to calculate the induced current in each of the 10k sensors.
- Sensor Response and 3-d track reconstruction. The induced current of each sensor is converted to the voltage signal using practical sensor parameters. While the x-y coordinates are determined by the sensor positions in the readout plane, the z coordinate is reconstructed utilizing the difference of velocities between $\mathrm{SeF_{5}^{-}}$ and $\mathrm{SeF_{6}^{-}}$.
- Background and signal event discrimination. Preliminary results show promising separation between signal and background based on the features of reconstructed 3D tracks. Further studies are ongoing, exploiting various methods.
Authors
tianyu liang
Hulin Wang
(Central China Normal University)
Dongliang Zhang
(华中师范大学)
Kai Chen
(Central China Normal University)
