Measurements using a prototype array of plastic scintillator bars for reactor based electron anti-neutrino detection

TL;DR

This study demonstrates the detection of reactor-based electron anti-neutrinos using a prototype plastic scintillator array, with detailed analysis and background estimation, achieving results consistent with theoretical predictions.

Contribution

First measurement of reactor anti-neutrinos using a plastic scintillator array with detailed event selection and background analysis techniques.

Findings

Detected 218 ± 50 (stat) ± 37 (sys) anti-neutrino events during reactor operation.

Results agree with the theoretical estimate of 214 ± 32 events.

Developed a data-driven background estimation and efficiency calculation method.

Abstract

We report measurement of reactor based electron anti-neutrinos from a prototype array of plastic scintillator bars ( mini-ISMRAN ) located inside Dhruva research reactor hall, BARC. The detector setup took data for 128 days for reactor on (RON) and 51 days for reactor off (ROFF) condition. A detailed analysis procedure is developed to select the anti-neutrino candidate events based on the energy deposition, number of bars hit as well as topological event selection criteria in position and time. Each of these selection criteria are compared with Monte Carlo based simulations and further an embedding technique is used to estimate the efficiencies from a data driven background study. The obtained anti-neutrino like events in RON condition are 218 $\pm$ 50 (stat) $\pm$ 37 (sys) after background subtraction. The obtained results are compared with theoretical estimation which yields 214 $\pm$ 32 (sys) anti-neutrino events for the RON condition.