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Expression of interest for the CODEX-b detector

Aielli, Giulio and Ben-Haim, Eli and Cardarelli, Roberto and Charles, Matthew John and Cid Vidal, Xabier and Coco, Victor and Dey, Biplab and Dumps, Raphael and Evans, Jared A. and Gibbons, George and Le Dortz, Olivier and Gligorov, Vladimir V. and Ilten, Philip and Knapen, Simon and Lee, Jongho and López Soliño, Saul and Nachman, Benjamin and Papucci, Michele and Polci, Francesco and Quessard, Robin and Ramani, Harikrishnan and Robinson, Dean J. and Schindler, Heinrich and Sokoloff, Michael D. and Swallow, Paul and Vari, Riccardo and Watson, Nigel and Williams, Mike (2020) Expression of interest for the CODEX-b detector. European Physical Journal. C, Particles and Fields, 80 (12). Art. No. 1177. ISSN 1434-6044.

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This document presents the physics case and ancillary studies for the proposed CODEX-b long-lived particle (LLP) detector, as well as for a smaller proof-of-concept demonstrator detector, CODEX-β, to be operated during Run 3 of the LHC. Our development of the CODEX-b physics case synthesizes ‘top-down’ and ‘bottom-up’ theoretical approaches, providing a detailed survey of both minimal and complete models featuring LLPs. Several of these models have not been studied previously, and for some others we amend studies from previous literature: In particular, for gluon and fermion-coupled axion-like particles. We moreover present updated simulations of expected backgrounds in CODEX-b’s actively shielded environment, including the effects of shielding propagation uncertainties, high-energy tails and variation in the shielding design. Initial results are also included from a background measurement and calibration campaign. A design overview is presented for the CODEX-β demonstrator detector, which will enable background calibration and detector design studies. Finally, we lay out brief studies of various design drivers of the CODEX-b experiment and potential extensions of the baseline design, including the physics case for a calorimeter element, precision timing, event tagging within LHCb, and precision low-momentum tracking.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Aielli, Giulio0000-0002-0573-8114
Cid Vidal, Xabier0000-0002-0468-541X
Coco, Victor0000-0002-5310-6808
Dey, Biplab0000-0002-4563-5806
Evans, Jared A.0000-0001-9871-6557
Gligorov, Vladimir V.0000-0002-8189-8267
Ilten, Philip0000-0001-5534-1732
Knapen, Simon0000-0002-6733-9231
Lee, Jongho0000-0003-0398-4220
Nachman, Benjamin0000-0003-1024-0932
Papucci, Michele0000-0003-0810-0017
Polci, Francesco0000-0001-8058-0436
Ramani, Harikrishnan0000-0003-3804-8598
Additional Information:© The Author(s) 2020. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit Received: 13 April 2020 / Accepted: 25 November 2020. Funded by SCOAP3. We thank Wolfgang Altmannshofer, Brian Batell, James Beacham, Florian Bernlochner, David Curtin, Francesco D’Eramo, Jeff Dror, Gilly Elor, Iftah Galon, Stefania Gori, Felix Kling, Gaia Lanfranchi, Zoltan Ligeti, Simone Pagan Griso, Hiren Patel, Gilad Perez, Maxim Pospelov, Josh Ruderman, Bibhushan Shakya, Jessie Shelton, Brian Shuve, Yotam Soreq, Yuhsin Tsai, Jure Zupan for many helpful discussions. We similarly thank all the members of the BSM working group of the Physics Beyond Colliders report. In addition, we thank Asher Berlin, Raffaele Tito D’Agnolo, Daniel Dercks, Jordy De Vries, Herbi K. Dreiner, Juan Carlos Helo, Martin Hirsch, Felix Kling, Dave McKeen and Zeren Simon Wang for generously providing plots for reproduction, with permission, as well as for comments on parts of the manuscript. We thank the computing and simulation teams of the LHCb collaboration for their generous help in performing the simulation studies presented here. We thank the LHCb technical coordination for making the background studies in the DELPHI cavern possible. We thank Giovanni Passaleva for his support and encouragement, and for helpful advice regarding the baseline RPC technology and the relationship between CODEX-b and LHCb. The work of XCV is supported by MINECO (Spain) through the Ramon y Cajal program RYC-2016-20073 and by XuntaGal under the ED431F 2018/01 project. JAE is supported by U.S. Department of Energy (DOE) grant DE-SC0011784. VVG is partially supported by ERC CoG “RECEPT” GA number 724777 within the H2020 framework programme. SK is supported by U.S. DOE grant DE-SC0009988 and the Paul Dirac fund at the Institute for Advanced Study. MP, DR and BN are supported by the U.S. DOE under contract DE-AC02-05CH11231. HR is supported in part by the U.S. DOE under contract DE-AC02-05CH11231. MW is supported by NSF grant PHY-1912836. Significant parts of this work were performed at: the Aspen Center for Physics, supported by National Science Foundation grant PHY-1607611; the Munich Institute for Astro- and Particle Physics (MIAPP); and the Galileo Galilei Institute for Theoretical Physics. We thank all these institutions for their support and hospitality. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility operated under Contract No. DE-AC02-05CH11231. This work has received nancial support from Xunta de Galicia (Centro singular de investigaciòn de Galicia accreditation 2019–2022), by European Union ERDF, and by the “Mara de Maeztu” Units of Excellence program MDM-2016-0692 and the Spanish Research State Agency. Data Availability Statement: This manuscript has no associated data or the data will not be deposited. [Authors’ comment: Uncalibrated data from the measurement campaign is available upon request.]
Group:Walter Burke Institute for Theoretical Physics
Funding AgencyGrant Number
Ramón y Cajal ProgrammeRYC-2016-20073
Xunta de GaliciaED431F 2018/01
Department of Energy (DOE)DE-SC0011784
European Research Council (ERC)724777
Department of Energy (DOE)DE-SC0009988
Institute for Advanced StudyUNSPECIFIED
Department of Energy (DOE)DE-AC02-05CH11231
Munich Institute for Astro- and Particle Physics (MIAPP)UNSPECIFIED
Galileo Galilei Institute for Theoretical PhysicsUNSPECIFIED
European Regional Development FundUNSPECIFIED
Ministerio de Ciencia, Innovación y Universidades (MCIU)MDM-2016-0692
Agencia Estatal de InvestigaciónUNSPECIFIED
Issue or Number:12
Record Number:CaltechAUTHORS:20201224-134252183
Persistent URL:
Official Citation:Aielli, G., Ben-Haim, E., Cardarelli, R. et al. Expression of interest for the CODEX-b detector. Eur. Phys. J. C 80, 1177 (2020).
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:107287
Deposited By: George Porter
Deposited On:04 Jan 2021 17:07
Last Modified:10 Apr 2021 00:50

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