Measurement of the two-photon absorption cross-section of liquid argon with a time projection chamber

Abstract

This paper reports on laser-induced multiphoton ionization at 266 nm of liquid argon in a time projection chamber (LAr TPC) detector. The electron signal produced by the laser beam is a formidable tool for the calibration and monitoring of next-generation large-mass LAr TPCs. The detector that we designed and tested allowed us to measure the two-photon absorption cross-section of LAr with unprecedented accuracy and precision: σex = (1.24±0.10stat ±0.30syst)× 10 -56 cm4 s-1. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.