Prospects of detecting the reactor $\overline{{\nu }_e}$-Ar coherent elastic scattering with a low threshold dual-phase argon time projection chamber at Taishan

Abstract

We propose to measure the coherent elastic neutrino nucleus scattering (CE$\nu$NS) using a dual-phase liquid argon time projection chamber (TPC) with 200kg fiducial mass. The detector is expected to be adjacent to the JUNO-TAO experiment and to be about 35m from a reactor core with 4.6GW thermal power at Taishan. The antineutrino flux is approximately 6$\times 10^{12}$cm${}^{-1}$s${}^{-1}$ at this location, leading to more than 11,000 coherent scattering events per day in the fiducial mass. However, the nuclear recoil energies concentrate in the sub-keV region, corresponding to less than ten ionisation electrons in the liquid argon. The detection of several ionisation electrons can be achieved in the dual-phase TPC due to the large amplification in the gas region. With a feasible detection threshold of four ionisation electrons, the signal rate is 955 per day. The detector is designed to be shielded well from cosmogenic backgrounds and ambient radioactivities to reach a 16% background-to-signal ratio in the energy region of interest. With the large CE$\nu$NS sample, the expected sensitivity of measuring the weak mixing angle ${\sin }^2{\theta }_W$, and of limiting the neutrino magnetic moment are discussed. In addition, a synergy between the reactor antineutrino CE$\nu$NS experiment and the dark matter experiment is foreseen.

14 pages, 10figures. Submitted to RDTM

References in corpus (7)

• Observation of Coherent Elastic Neutrino-Nucleus Scattering
• First Results from the DarkSide-50 Dark Matter Experiment at Laboratori Nazionali del Gran Sasso
• Improved Measurement of the Reactor Antineutrino Flux and Spectrum at Daya Bay
• Constraints on elastic neutrino nucleus scattering in the fully coherent regime from the CONUS experiment
• Physics results from the first COHERENT observation of CE$\nu$NS in argon and their combination with cesium-iodide data
• TAO Conceptual Design Report: A Precision Measurement of the Reactor Antineutrino Spectrum with Sub-percent Energy Resolution
• Recent probes of standard and non-standard neutrino physics with nuclei