Prototype Development and Test Beam Results of the ALICE FoCal-H Calorimeter

Prototype Development and Test Beam Results of the ALICE FoCal-H Calorimeter | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Prototype Development and Test Beam Results of the ALICE FoCal-H Calorimeter Shihai Jia, Ian Pascal Moller, Nicola Minafra, Tommaso Isidori, and 7 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9497415/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract The ALICE FoCal upgrade is proposed primarily to measure forward direct photons and neutral pions in the pseudorapidity range of 3.4 < η < 5.5 with full azimuthal acceptance to constrain the gluon parton distribution functions in nucleons and nuclei down to x ∼ 10 −6 and to study the possible onset of gluon saturation in nuclei. FoCal consists of a high-granularity electromagnetic part (FoCal-E) and a hadronic part (FoCal-H). FoCal-H is a sampling calorimeter with copper absorbers and scintillator fibers as the active material. Its design has been optimized using Monte Carlo simulations. A new FoCal-H prototype was built and tested with particle beams at CERN SPS. In this paper, we present the design of the new prototype, the detector performance in test beams, and the implementation of a new readout chain. The measured energy response and resolution are found to be in good agreement with simulation, and an improvement in resolution is observed with respect to the previous prototypes, demonstrating the suitability of the new mechanical and readout design for the FoCal-H detector. Forward calorimetry Copper-scintillator calorimeter H2GCROC readout Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 19 May, 2026 Reviewers agreed at journal 18 May, 2026 Reviewers agreed at journal 16 May, 2026 Reviewers invited by journal 14 May, 2026 Editor assigned by journal 25 Apr, 2026 Submission checks completed at journal 23 Apr, 2026 First submitted to journal 22 Apr, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9497415","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":640646164,"identity":"79a5400e-86ef-4b40-bea6-e117610504dc","order_by":0,"name":"Shihai Jia","email":"","orcid":"","institution":"China Institute of Atomic Energy","correspondingAuthor":false,"prefix":"","firstName":"Shihai","middleName":"","lastName":"Jia","suffix":""},{"id":640646165,"identity":"bd44cc75-b933-475e-9480-30f9cf408584","order_by":1,"name":"Ian Pascal Moller","email":"","orcid":"","institution":"University of 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