First results on ProtoDUNE-SP liquid argon time projection chamber performance from a beam test at the CERN Neutrino Platform

Abstract

The ProtoDUNE-SP detector is a single-phase liquid argon time projection chamber with an active volume of 7.2× 6.1× 7.0 m3. It is installed at the CERN Neutrino Platform in a specially-constructed beam that delivers charged pions, kaons, protons, muons and electrons with momenta in the range 0.3 GeV/c to 7 GeV/c. Beam line instrumentation provides accurate momentum measurements and particle identification. The ProtoDUNE-SP detector is a prototype for the first far detector module of the Deep Underground Neutrino Experiment, and it incorporates full-size components as designed for that module. This paper describes the beam line, the time projection chamber, the photon detectors, the cosmic-ray tagger, the signal processing and particle reconstruction. It presents the first results on ProtoDUNE-SP's performance, including noise and gain measurements, dE/dx calibration for muons, protons, pions and electrons, drift electron lifetime measurements, and photon detector noise, signal sensitivity and time resolution measurements. The measured values meet or exceed the specifications for the DUNE far detector, in several cases by large margins. ProtoDUNE-SP's successful operation starting in 2018 and its production of large samples of high-quality data demonstrate the effectiveness of the single-phase far detector design.

Space Charge Effects in Noble-Liquid Calorimeters and Time Projection Chambers

“…The ProtoDUNE Single-Phase LAr TPC has collected data at the CERN Neutrino Platform. The detector has an active volume of 7.2 × 6.0 × 6.9 m 3 , with a cathode plane separating two regions with drift gaps of 3.6 m. Operated at 500 V cm −1 , the parameter α is about 20% smaller than in MicroBooNE, but space charge effects are expected to be larger, because spatial distortion scales approximately as α L. Figure 6 [15] shows the transverse distortions to the tracks end-points, when they cross the top or bottom face of the active volume. The drift occurs horizontally, along x, with the cathode at x = 0 in these plots.…”

“…The distortion in the bottom panels is qualitatively comparable, but reaches larger values and shows large asymmetries between the top and bottom faces, and between the two sides of the cathode surface. Reproduced from reference[15].…”

Calibrating the DUNE LArTPC Detectors for Precision Physics

“…The single-phase detector, ProtoDUNE-SP, was exposed to particle beams in 2018, and has been collecting cosmic-ray data since then. Procedures for calibration have been developed and the detector has shown excellent performance [5].…”

Calibration of Calorimetric Measurement in a Liquid Argon Time Projection Chamber

“…Many LArTPC experiments have an electronics calibration system that has the capability to inject a known charge into each of the amplifiers connected to the TPC wires. In the ProtoDUNE pulser calibration system [2], the injected charge Q is controlled by a six-bit-voltage digital-to-analog converter (DAC):…”