In:
Journal of Instrumentation, IOP Publishing, Vol. 19, No. 08 ( 2024-08-01), p. P08005-
Abstract:
Doping of liquid argon TPCs (LArTPCs) with a small
concentration of xenon is a technique for light-shifting and facilitates the detection of the liquid argon scintillation
light. In this paper, we present the results of the first doping test ever performed in a kiloton-scale LArTPC. From February to May
2020, we carried out this special run in the single-phase DUNE Far Detector prototype (ProtoDUNE-SP) at CERN, featuring 720 t of total
liquid argon mass with 410 t of fiducial mass. A 5.4 ppm nitrogen contamination was present during the xenon doping campaign. The goal
of the run was to measure the light and charge response of the detector to the addition of xenon, up to a concentration of
18.8 ppm. The main purpose was to test the possibility for reduction of non-uniformities in light collection, caused by
deployment of photon detectors only within the anode planes. Light collection was analysed as a function of the xenon concentration, by
using the pre-existing photon detection system (PDS) of ProtoDUNE-SP and an additional smaller set-up installed specifically for this
run. In this paper we first summarize our current understanding of the argon-xenon energy transfer process and the impact of the
presence of nitrogen in argon with and without xenon dopant. We then describe the key elements of ProtoDUNE-SP and the injection method
deployed. Two dedicated photon detectors were able to collect the light produced by xenon and the total light. The ratio of these
components was measured to be about 0.65 as 18.8 ppm of xenon were injected. We performed studies of the collection efficiency as a
function of the distance between tracks and light detectors, demonstrating enhanced uniformity of response for the anode-mounted
PDS. We also show that xenon doping can substantially recover light losses due to contamination of the liquid argon by nitrogen.
Type of Medium:
Online Resource
ISSN:
1748-0221
DOI:
10.1088/1748-0221/19/08/P08005
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
2024
detail.hit.zdb_id:
2235672-1
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