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Performance of the Eos detector with water

S. Arora^1,2, M. Askins^1,2, A. J. Bacon³, Z. Bagdasarian^1,2, A. Baldoni^4,5, L. Bartoszek⁶, M. Bergevin⁷, Y. Bezawada^1,2, E. Blucher⁸ et al.

J. Boissevain⁶, R. Bonventre², E. J. Callaghan^1,2, D. F. Cowen⁴, K. DeHolton⁴, M. Diwan⁹, M. Dubnowski³, P. Englezos^1,2, S. Gadamsetty^1,2, C. Grant¹⁰, B. Harris³, M. R. Hebert^1,2, S. Jeon¹⁰, T. Kaptanoglu ^1,2,*, A. Katt¹⁰, J. R. Klein³, T. Kroupová³, L. Lebanowski^1,2, S. Lynch^1,2, A. Mastbaum¹¹, C. Mauger³, G. Mayers³, M. Miller¹², J. Nachtman¹², S. Naugle³, J. Newby¹³, M. Newcomer³, A. Nikolica³, G. D. Orebi Gann^1,2, A. Phipps¹⁴, L. Pickard^1,2, R. C. Pitelka³, L. Ren¹⁵, A. Rincon^1,2, R. Rosero⁹, N. Rowe^1,2, H. J. Ryoo^1,2, J. Ryshkewitch¹⁰, J. Saba², S. Schoppmann^1,2, J. Shen³, M. Smiley^1,2, H. Song^1,2,10, H. Steiger^16,17, B. Tam¹⁸, E. Tiras^19,12, W. H. To²⁰, M. R. Vagins²¹, R. Van Berg⁶, J. Wallig², G. Wendel⁴, M. Wetstein²², M. Wurm¹⁶, G. Yang^1,2, M. Yeh⁹, E. D. Zimmerman¹⁵, and A. Zummo¹¹

¹Physics Department, University of California at Berkeley, Berkeley, California 94720-7300, USA
²Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720-8153, USA
³Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6396, USA
⁴Department of Physics, Pennsylvania State University, University Park, Pennsylvania 16802, USA
⁵United States Military Academy, Department of Physics and Nuclear Engineering, West Point, New York 10996, USA
⁶Bartoszek Engineering, Aurora, Illinois 60506, USA
⁷Lawrence Livermore National Laboratory, Livermore, California 94550, USA
⁸The Enrico Fermi Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637, USA
⁹Brookhaven National Laboratory, Upton, New York 11973, USA
¹⁰Boston University, Department of Physics, Boston, Massachusetts 02215, USA
¹¹Department of Physics and Astronomy, Rutgers, The State University of New Jersey, 136 Frelinghuysen Road, Piscataway, New Jersey 08854-8019 USA
¹²Department of Physics and Astronomy, The University of Iowa, Iowa City, Iowa 52242, USA
¹³Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee 37830
¹⁴California State University, East Bay, Department of Physics, 25800 Carlos Bee Boulevard, Hayward, California 94542, USA
¹⁵University of Colorado at Boulder, Department of Physics, Boulder, Colorado 80309, USA
¹⁶Johannes Gutenberg-Universität, Institute of Physics and EC PRISMA⁺⁺, Mainz, 55099 Mainz, Germany
¹⁷Physics Department, Technische Universität München, 85748 Garching, Germany
¹⁸Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
¹⁹Department of Physics, Erciyes University, 38030, Kayseri, Turkey
²⁰California State University, Stanislaus, Department of Physics, Turlock, California 95382, USA
²¹Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-4575, USA
²²Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA

^*Contact author: tannerbk@berkeley.edu

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Phys. Rev. D 114, 052012 – Published 21 September, 2026

DOI: https://doi.org/10.1103/7qkt-mnqz

Abstract

In this manuscript we present the first results from Eos, a four tonne optical detector located at the University of California, Berkeley. The primary goal of Eos is to demonstrate the performance capabilities of scintillation-based, “hybrid” detector technology for future neutrino detectors. The data presented were collected while both the inner target vessel and the outer buffer vessel were filled with water. The water target acts as a well-understood medium that produces only Cherenkov light, which can be used to calibrate and develop the detector model and reconstruction algorithms prior to the deployment of scintillating material. Using deployed optical and radioactive calibration sources, a series of detailed detector calibrations are performed. These enable a suite of tests for various reconstruction algorithms. Simulations that use calibrated models are compared with the data across a variety of different types of calibration sources, source positions, and rotations.

Physics Subject Headings (PhySH)

Neutrino detection

Article Text

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Phys. Rev. D 114, 052012– Published 21 September, 2026

Vol. 114, Iss. 5 — 1 September 2026

Received 15 June 2026
Accepted 31 August 2026

DOI: https://doi.org/10.1103/7qkt-mnqz

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP³.

Published by the American Physical Society

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Performance of the Eos detector with water

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