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

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...

Full description

Autores:
Acero, M.A.
Tipo de recurso:
Fecha de publicación:
2020
Institución:
Universidad del Atlántico
Repositorio:
Repositorio Uniatlantico
Idioma:
eng
OAI Identifier:
oai:repositorio.uniatlantico.edu.co:20.500.12834/951
Acceso en línea:
https://hdl.handle.net/20.500.12834/951
Palabra clave:
Large detector systems for particle and astroparticle physics; Noble liquid detectors (scintillation, ionization, double-phase); Time projection Chambers (TPC)
Rights
openAccess
License
http://creativecommons.org/licenses/by-nc/4.0/
id UNIATLANT2_0cfb1946cb297c81c79ea0ab70a673ec
oai_identifier_str oai:repositorio.uniatlantico.edu.co:20.500.12834/951
network_acronym_str UNIATLANT2
network_name_str Repositorio Uniatlantico
repository_id_str
dc.title.spa.fl_str_mv First results on ProtoDUNE-SP liquid argon time projection chamber performance from a beam test at the CERN Neutrino Platform
title First results on ProtoDUNE-SP liquid argon time projection chamber performance from a beam test at the CERN Neutrino Platform
spellingShingle First results on ProtoDUNE-SP liquid argon time projection chamber performance from a beam test at the CERN Neutrino Platform
Large detector systems for particle and astroparticle physics; Noble liquid detectors (scintillation, ionization, double-phase); Time projection Chambers (TPC)
title_short First results on ProtoDUNE-SP liquid argon time projection chamber performance from a beam test at the CERN Neutrino Platform
title_full First results on ProtoDUNE-SP liquid argon time projection chamber performance from a beam test at the CERN Neutrino Platform
title_fullStr First results on ProtoDUNE-SP liquid argon time projection chamber performance from a beam test at the CERN Neutrino Platform
title_full_unstemmed First results on ProtoDUNE-SP liquid argon time projection chamber performance from a beam test at the CERN Neutrino Platform
title_sort First results on ProtoDUNE-SP liquid argon time projection chamber performance from a beam test at the CERN Neutrino Platform
dc.creator.fl_str_mv Acero, M.A.
dc.contributor.author.none.fl_str_mv Acero, M.A.
dc.subject.keywords.spa.fl_str_mv Large detector systems for particle and astroparticle physics; Noble liquid detectors (scintillation, ionization, double-phase); Time projection Chambers (TPC)
topic Large detector systems for particle and astroparticle physics; Noble liquid detectors (scintillation, ionization, double-phase); Time projection Chambers (TPC)
description 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/. 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, 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.
publishDate 2020
dc.date.issued.none.fl_str_mv 2020-12-03
dc.date.submitted.none.fl_str_mv 2020-07-30
dc.date.accessioned.none.fl_str_mv 2022-11-15T21:12:39Z
dc.date.available.none.fl_str_mv 2022-11-15T21:12:39Z
dc.type.coarversion.fl_str_mv http://purl.org/coar/version/c_970fb48d4fbd8a85
dc.type.coar.fl_str_mv http://purl.org/coar/resource_type/c_2df8fbb1
dc.type.driver.spa.fl_str_mv info:eu-repo/semantics/article
dc.type.hasVersion.spa.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.spa.spa.fl_str_mv Artículo
status_str publishedVersion
dc.identifier.uri.none.fl_str_mv https://hdl.handle.net/20.500.12834/951
dc.identifier.doi.none.fl_str_mv 10.1088/1748-0221/15/12/P12004
dc.identifier.instname.spa.fl_str_mv Universidad del Atlántico
dc.identifier.reponame.spa.fl_str_mv Repositorio Universidad del Atlántico
url https://hdl.handle.net/20.500.12834/951
identifier_str_mv 10.1088/1748-0221/15/12/P12004
Universidad del Atlántico
Repositorio Universidad del Atlántico
dc.language.iso.spa.fl_str_mv eng
language eng
dc.rights.coar.fl_str_mv http://purl.org/coar/access_right/c_abf2
dc.rights.uri.*.fl_str_mv http://creativecommons.org/licenses/by-nc/4.0/
dc.rights.cc.*.fl_str_mv Attribution-NonCommercial 4.0 International
dc.rights.accessRights.spa.fl_str_mv info:eu-repo/semantics/openAccess
rights_invalid_str_mv http://creativecommons.org/licenses/by-nc/4.0/
Attribution-NonCommercial 4.0 International
http://purl.org/coar/access_right/c_abf2
eu_rights_str_mv openAccess
dc.format.mimetype.spa.fl_str_mv application/pdf
dc.publisher.place.spa.fl_str_mv Barranquilla
dc.publisher.sede.spa.fl_str_mv Sede Norte
dc.source.spa.fl_str_mv Journal of Instrumentation
institution Universidad del Atlántico
bitstream.url.fl_str_mv https://repositorio.uniatlantico.edu.co/bitstream/20.500.12834/951/1/Abi_2020_J._Inst._15_P12004%20%281%29.pdf
https://repositorio.uniatlantico.edu.co/bitstream/20.500.12834/951/2/license_rdf
https://repositorio.uniatlantico.edu.co/bitstream/20.500.12834/951/3/license.txt
bitstream.checksum.fl_str_mv 9344881db0f1601d3267d04f6266da09
24013099e9e6abb1575dc6ce0855efd5
67e239713705720ef0b79c50b2ececca
bitstream.checksumAlgorithm.fl_str_mv MD5
MD5
MD5
repository.name.fl_str_mv DSpace de la Universidad de Atlántico
repository.mail.fl_str_mv sysadmin@mail.uniatlantico.edu.co
_version_ 1814203418359627776
spelling Acero, M.A.979f9c6a-faae-415d-b017-8ea1e9afa74c2022-11-15T21:12:39Z2022-11-15T21:12:39Z2020-12-032020-07-30https://hdl.handle.net/20.500.12834/95110.1088/1748-0221/15/12/P12004Universidad del AtlánticoRepositorio Universidad del AtlánticoThe 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/. 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, 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.application/pdfenghttp://creativecommons.org/licenses/by-nc/4.0/Attribution-NonCommercial 4.0 Internationalinfo:eu-repo/semantics/openAccesshttp://purl.org/coar/access_right/c_abf2Journal of InstrumentationFirst results on ProtoDUNE-SP liquid argon time projection chamber performance from a beam test at the CERN Neutrino PlatformPúblico generalLarge detector systems for particle and astroparticle physics; Noble liquid detectors (scintillation, ionization, double-phase); Time projection Chambers (TPC)info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArtículohttp://purl.org/coar/version/c_970fb48d4fbd8a85http://purl.org/coar/resource_type/c_2df8fbb1BarranquillaSede Norte[1] DUNE collaboration, Deep Underground Neutrino Experiment (DUNE), Far Detector Technical Design Report. Volume I: introduction to DUNE, arXiv:2002.02967.[2] ICARUS collaboration, Design, construction and tests of the ICARUS T600 detector, Nucl. Instrum. Meth. A 527 (2004) 329.[3] DUNE collaboration, The single-phase ProtoDUNE technical design report, arXiv:1706.07081[4] F. Pietropaolo, Review of liquid-argon detectors development at the CERN neutrino platform, J. Phys. Conf. Ser. 888 (2017) 012038.[5] DUNE collaboration, Deep Underground Neutrino Experiment (DUNE), far detector technical design report. Volume IV: far detector single-phase technology, arXiv:2002.03010[6] DUNE collaboration, Deep Underground Neutrino Experiment (DUNE), far detector technical design report. Volume II: DUNE physics, arXiv:2002.03005.[7] C. Anderson et al., The ArgoNeuT detector in the NuMI low-energy beam line at Fermilab, 2012 JINST 7 P10019 [arXiv:1205.6747].[8] C. Bromberg et al., Design and Operation of LongBo: a 2 m long drift liquid Argon TPC, 2015 JINST 10 P07015 [arXiv:1504.00398][9] MicroBooNE collaboration, Design and construction of the MicroBooNE Detector, 2017 JINST 12 P02017 [arXiv:1612.05824].[10] D.L. Adams et al., Design and performance of a 35-ton liquid argon time projection chamber as a prototype for future very large detectors, 2020 JINST 15 P03035 [arXiv:1912.08739].[11] DUNE collaboration, Design, construction and operation of the ProtoDUNE-SP liquid argon TPC, in preparation.[12] D. Montanari et al., Development of membrane cryostats for large liquid argon neutrino detectors, IOP Conf. Ser. Mater. Sci. Eng. 101 (2015) 012049.[13] P. Benetti et al., Argon purification in the liquid phase, Nucl. Instrum. Meth. A 333 (1993) 567[14] M. Adamowski et al., The Liquid Argon Purity Demonstrator, 2014 JINST 9 P07005 [arXiv:1403.7236].[15] A. Bettini et al., A study of the factors affecting the electron lifetime in ultra-pure liquid argon, Nucl. Instrum. Meth. A 305 (1991) 177.[16] G.J. Michna, S.P. Gent, D. Pederson and C. Streff, CFD analysis of the fluid, heat, and impurity flows in ProtoDUNE single phase detector, DUNE-Doc-17481-v1 (2019).[17] G. De Geronimo et al., Front-end ASIC for a Liquid Argon TPC, IEEE Trans. Nucl. Sci. 58 (2011) 1376[18] D. Adams et al., The ProtoDUNE-SP LArTPC electronics production, commissioning, and performance, 2020 JINST 15 P06017 [arXiv:2002.01782][19] F. Acerbi and S. Gundacker, Understanding and simulating SiPMs, Nucl. Instrum. Meth. A 926 (2019) 16[20] E.M. Conover, Muon-induced backgrounds in the Double Chooz neutrino oscillation experiment, Ph.D. thesis, The University of Chicago, Chicago, U.S.A. (2014[21] R. Herbst et al., Design of the SLAC RCE Platform: a general purpose ATCA based data acquisition system, in the proceedings of the 21st Symposium on Room-Temperature Semiconductor X-ray and Gamma-ray Detectors (RTSD 2014), November 8–15, Seattle, U.S.A. (2014).[22] K.V. Tsang, M. Convery, M. Graham, R. Herbst and J. Russell, The SLAC RCE platform for ProtoDUNE, EPJ Web Conf. 214 (2019) 01025.[23] J. Anderson et al., FELIX: a PCIe based high-throughput approach for interfacing front-end and trigger electronics in the ATLAS Upgrade framework, 2016 JINST 11 C12023[24] A. Borga et al., FELIX based readout of the single-phase ProtoDUNE detector, IEEE Trans. Nucl. Sci. 66 (2019) 993 [arXiv:1806.09194][25] K. Biery, C. Green, J. Kowalkowski, M. Paterno and R. Rechenmacher, artdaq: an event-building, filtering, and processing framework, IEEE Trans. Nucl. Sci. 60 (2013) 3764.[26] N. Charitonidis and I. Efthymiopoulos, Low energy tertiary beam line design for the CERN neutrino platform project, Phys. Rev. Accel. Beams 20 (2017) 111001[27] A.C. Booth et al., Particle production, transport, and identification in the regime of 1–7 GeV/c, Phys. Rev. Accel. Beams 22 (2019) 061003.[28] I. Ortega Ruiz, Accurate profile measurement of the low intensity secondary beams in the CERN experimental areas, Ph.D. thesis, Ecole Polytechnique, Lausanne, Switzerland (2018).[29] FMC Time to Digital Converter | FMC TDC 1ns 5cha, https://ohwr.org/project/fmc-tdc/wikis/home[30] N. Charitonidis, I. Efthymiopoulos and Y. Karyotakis, Beam performance and instrumentation studies for the ProtoDUNE-DP experiment of CENF, Tech. Rep. CERN-ACC-NOTE-2016-0052. 27, CERN, Geneva (Jul, 2016)[31] N. Charitonidis, Y. Karyotakis and L. Gatignon, Estimation of the R134a gas refractive index for use as a Cherenkov radiator, using a high energy charged particle beam, Nucl. Instrum. Meth. B 410 (2017) 134.[32] D. Carey, K. Brown and F. Rothacker, Third-order TRANSPORT: a computer program for designing charged particle beam transport systems, SLAC-R-462 (1995).[33] Methodical Accelerator Design CERN, http://mad.web.cern.ch/mad/[34] P. K. Skowronski, F. Schmidt and E. Forest, Advances in MAD X using PTC, Conf. Proc. C070625 (2007) 3381[35] P. Chatzidaki, Optics optimization of tertiary particle beamlines and efficiency measurement of prototype scintillating fiber detectors, Diploma thesis, National Technical University, Athens, Greece (2018).[36] T.J. Roberts et al., G4Beamline particle tracking in matter-dominated beam lines, Conf. Proc. C0806233 (2008) WEPP120[37] T.T. Böhlen et al., The FLUKA Code: developments and challenges for high energy and medical applications, Nucl. Data Sheets 120 (2014) 211[38] A. Ferrari, P.R. Sala, A. Fasso and J. Ranft, FLUKA: a multi-particle transport code (Program version 2005), CERN-2005-010[39] MicroBooNE collaboration, Noise characterization and filtering in the MicroBooNE Liquid Argon TPC, 2017 JINST 12 P08003 [arXiv:1705.07341].[40] S. Ramo, Currents induced by electron motion, Proc. Ire. 27 (1939) 584.[41] R. Veenhof, GARFIELD, recent developments, Nucl. Instrum. Meth. A 419 (1998) 726[42] Y. Li et al., Measurement of Longitudinal Electron Diffusion in Liquid Argon, Nucl. Instrum. Meth. A 816 (2016) 160 [arXiv:1508.07059].[43] C. Zhang, Summary of liquid argon properties, http://lar.bnl.gov/properties/.[44] MicroBooNE collaboration, Ionization electron signal processing in single phase LArTPCs. Part I. Algorithm description and quantitative evaluation with MicroBooNE simulation, 2018 JINST 13 P07006 [arXiv:1802.08709].[45] MicroBooNE collaboration, Ionization electron signal processing in single phase LArTPCs. Part II. Data/simulation comparison and performance in MicroBooNE, 2018 JINST 13 P07007 [arXiv:1804.02583][46] J.S. Marshall and M.A. Thomson, The Pandora software development kit for pattern recognition, Eur. Phys. J. C 75 (2015) 439 [arXiv:1506.05348].[47] MicroBooNE collaboration, The Pandora multi-algorithm approach to automated pattern recognition of cosmic-ray muon and neutrino events in the MicroBooNE detector, Eur. Phys. J. C 78 (2018) 82 [arXiv:1708.03135].[48] A.A. Machado and E. Segreto, ARAPUCA a new device for liquid argon scintillation light detection, 2016 JINST 11 C02004.[49] Z. Moss et al., A factor of four increase in attenuation length of dipped lightguides for liquid argon TPCs through improved coating, arXiv:1604.03103.[50] L. Bugel et al., Demonstration of a lightguide detector for liquid argon TPCs, Nucl. Instrum. Meth. A 640 (2011) 69 [arXiv:1101.3013].[51] B. Howard et al., A novel use of light guides and wavelength shifting plates for the detection of scintillation photons in large liquid argon detectors, Nucl. Instrum. Meth. A 907 (2018) 9 [arXiv:1710.11233].[52] L. Condat, A direct algorithm for 1���������������������� total variation denoising, IEEE Signal Proc. Lett. 20 (2013) 1054[53] E.D. Church, LArSoft: a software package for Liquid Argon Time Projection Drift Chambers, arXiv:1311.6774.[54] C. Zhang, Wire-cell BEE event display, https://www.phy.bnl.gov/twister/bee[55] T. Doke et al., Absolute scintillation yields in liquid argon and xenon for various particles, Jap. J. Appl. Phys. 41 (2002) 1538.[56] M. Babicz et al., Experimental study of the propagation of scintillation light in Liquid Argon, Nucl. Instrum. Meth. A 936 (2019) 178.[57] M. Babicz et al., A measurement of the group velocity of scintillation light in liquid argon, 2020 JINST 15 P09009 [arXiv:2002.09346][58] M. Mooney, The MicroBooNE experiment and the impact of space charge effects, in Meeting of the APS Division of Particles and Fields, 11, 2015 [arXiv:1511.01563].[59] MicroBooNE collaboration, Measurement of space charge effects in MicroBooNE, MICROBOONE-NOTE-1018-PUB[60] MicroBooNE collaboration, A method to determine the electric field of liquid argon time projection chambers using a UV laser system and its application in MicroBooNE, 2020 JINST 15 P07010 [arXiv:1910.01430].[61] MicroBooNE collaboration, Calibration of the charge and energy loss per unit length of the MicroBooNE liquid argon time projection chamber using muons and protons, 2020 JINST 15 P03022 [arXiv:1907.11736].[62] Particle Data Group collaboration, Review of particle physics, Phys. Rev. D 98 (2018) 030001.[63] ArgoNeuT collaboration, A study of electron recombination using highly ionizing particles in the ArgoNeuT Liquid Argon TPC, 2013 JINST 8 P08005 [arXiv:1306.1712][64] Muon stopping power and range tables 10 MeV–100 TeV, http://pdg.lbl.gov/2019/AtomicNuclearProperties/adndt.pdf.[65] ArgoNeuT collaboration, First observation of low energy electron neutrinos in a Liquid Argon Time Projection Chamber, Phys. Rev. D 95 (2017) 072005 [arXiv:1610.04102][66] LArIAT collaboration, Calorimetry for low-energy electrons using charge and light in liquid argon, Phys. Rev. D 101 (2020) 012010 [arXiv:1909.07920][67] DUNE collaboration, First calorimetric energy reconstruction of beam events with ARAPUCA light detector in ProtoDUNE-SP, 2020 JINST 15 C03033[68] C.W. Fabjan and F. Gianotti, Calorimetry for particle physics, Rev. Mod. Phys. 75 (2003) 1243.http://purl.org/coar/resource_type/c_6501ORIGINALAbi_2020_J._Inst._15_P12004 (1).pdfAbi_2020_J._Inst._15_P12004 (1).pdfapplication/pdf32945924https://repositorio.uniatlantico.edu.co/bitstream/20.500.12834/951/1/Abi_2020_J._Inst._15_P12004%20%281%29.pdf9344881db0f1601d3267d04f6266da09MD51CC-LICENSElicense_rdflicense_rdfapplication/rdf+xml; charset=utf-8914https://repositorio.uniatlantico.edu.co/bitstream/20.500.12834/951/2/license_rdf24013099e9e6abb1575dc6ce0855efd5MD52LICENSElicense.txtlicense.txttext/plain; charset=utf-81306https://repositorio.uniatlantico.edu.co/bitstream/20.500.12834/951/3/license.txt67e239713705720ef0b79c50b2ececcaMD5320.500.12834/951oai:repositorio.uniatlantico.edu.co:20.500.12834/9512022-11-15 16:12:40.584DSpace de la Universidad de Atlánticosysadmin@mail.uniatlantico.edu.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