Elsevier B.V. : Picosecond timing of charged particles using the TORCH detector

Cicala, Maria Flavia; Forty, Roger; Cussans, David; Hancock, Thomas Henry; Gys, Thierry; Gao, Rui; Gabriel, Emmy P.M.; Jones, Thomas; Gershon, Timothy; Rademacker, Jonas; Hadavizadeh, Thomas; Milnes, James; Bhasin, Srishti; Frei, Christoph; Piedigrossi, Didier; Conneely, Thomas; Blake, Thomas; Smallwood, Jennifer Clare; Brook, Nick H.; van Dijk, Maarten W.U.; Kreps, Michal; Harnew, Neville

doi:10.1016/j.nima.2022.166950

Article
Report number	arXiv:2203.13774
Title	Picosecond timing of charged particles using the TORCH detector
Author(s)	Cicala, Maria Flavia (Warwick U.) ; Bhasin, Srishti (Bath U. ; Bristol U.) ; Blake, Thomas (Warwick U.) ; Brook, Nick H. (Bath U.) ; Conneely, Thomas (Unlisted, UK) ; Cussans, David (Bristol U.) ; van Dijk, Maarten W.U. (CERN) ; Forty, Roger (CERN) ; Frei, Christoph (CERN) ; Gabriel, Emmy P.M. (Edinburgh U.) ; Gao, Rui (Oxford U.) ; Gershon, Timothy (Warwick U.) ; Gys, Thierry (CERN) ; Hadavizadeh, Thomas (Oxford U.) ; Hancock, Thomas Henry (Oxford U.) ; Harnew, Neville (Oxford U.) ; Jones, Thomas (Warwick U.) ; Kreps, Michal (Warwick U.) ; Milnes, James (Unlisted, UK) ; Piedigrossi, Didier (CERN) ; Rademacker, Jonas (Bristol U.) ; Smallwood, Jennifer Clare (Oxford U.)
Publication	2022-09-01
Imprint	2022-03-25
Number of pages	13
Note	Vienna Instrumentation Conference 2022 proceedings. 13 pages,5 figures, 1 table
In:	Nucl. Instrum. Methods Phys. Res., A 1038 (2022) pp.166950
In:	Vienna Conference on Instrumentation (VCI 2022), Online, Austria, 21 - 25 Feb 2022, pp.166950
DOI	10.1016/j.nima.2022.166950 (publication)
Subject category	hep-ex ; Particle Physics - Experiment ; physics.ins-det ; Detectors and Experimental Techniques
Abstract	TORCH is a large-area, high-precision time-of-flight (ToF) detector designed to provide charged-particle identification in the 2-20 GeV$/c$ momentum range. Prompt Cherenkov photons emitted by charged hadrons as they traverse a 10mm quartz radiator are propagated to the periphery of the detector, where they are focused onto an array of micro-channel plate photomultiplier tubes (MCP-PMTs). The position and arrival times of the photons are used to infer the particles' time of entry in the radiator, to identify hadrons based on their ToF. The MCP-PMTs were developed with an industrial partner to satisfy the stringent requirements of the TORCH detector. The requirements include a finely segmented anode, excellent time resolution, and a long lifetime. Over an approximately 10m flight distance, the difference in ToF between a kaon and a pion with 10GeV$/c$ momentum is 35ps, leading to a 10-15ps per track timing resolution requirement. On average 30 photons per hadron are detected, which translates to a single-photon time resolution of 70ps. The TORCH research and development program aims to demonstrate the validity of the detector concept through laboratory and beam tests, results from which are presented. A timing resolution of 70-100ps was reached in beam tests, approaching the TORCH design goal. Laboratory timing tests consist of operating the MCP-PMTs coupled to the TORCH readout electronics. A time resolution of about 50ps was measured, meeting the TORCH target timing resolution.
Copyright/License	publication: © 2022-2025 The Author(s) (License: CC BY 4.0) preprint: (License: CC BY 4.0)