Eur. Phys. J. C (2020) 80: 416
https://doi.org/10.1140/epjc/s10052-020-7977-8

Regular Article - Experimental Physics

Theia: an advanced optical neutrino detector

¹ Department of Physics, University of California, Berkeley, Berkeley, CA, 94720, USA
² Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720-8153, USA
³ Forschungszentrum Jülich, Institute for Nuclear Physics, Wilhelm-Johnen-Straße, 52425, Jülich, Germany
⁴ Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA, 19104-6396, USA
⁵ Faculdade de Ciências (FCUL), Departamento de Física, Campo Grande, Edifício C8, Universidade de Lisboa, 1749-016, Lisbon, Portugal
⁶ Laboratório de Instrumentação e Física Experimental de Partículas (LIP), Av. Prof. Gama Pinto, 2, 1649-003, Lisbon, Portugal
⁷ Department of Physics, The Enrico Fermi Institute, The University of Chicago, Chicago, IL, 60637, USA
⁸ Brookhaven National Laboratory, Upton, NY, 11973, USA
⁹ University of Hawai’i at Manoa, Honolulu, HI, 96822, USA
¹⁰ Department of Physics and Astronomy, Iowa State University, Ames, IA, 50011, USA
¹¹ Department of Physics, University of Jyväskylä, Jyvaskyla, Finland
¹² University of California, Davis, 1 Shields Avenue, Davis, CA, 95616, USA
¹³ Department of Physics, Boston University, Boston, MA, 02215, USA
¹⁴ Institute of Physics and Excellence Cluster PRISMA, Johannes Gutenberg-Universität Mainz, 55099, Mainz, Germany
¹⁵ Institut für Experimentalphysik, Universität Hamburg, 22761, Hamburg, Germany
¹⁶ Department of Physics, University of Alberta, 4-181 CCIS, Edmonton, AB, T6G 2E1, Canada
¹⁷ Pacific Northwest National Laboratory, Richland, WA, 99352, USA
¹⁸ Department of Physics, Laurentian University, 935 Ramsey Lake Road, Sudbury, ON, P3E 2C6, Canada
¹⁹ Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA, 70803, USA
²⁰ Kepler Center for Astro and Particle Physics, Universität Tübingen, 72076, Tübingen, Germany
²¹ Physics and Astronomy, Western Bank, University of Sheffield, Sheffield, S10 2TN, UK
²² Department of Physics, Engineering Physics and Astronomy, Queen’s University, Kingston, ON, K7L 3N6, Canada
²³ SNOLAB, Creighton Mine 9, 1039 Regional Road 24, Sudbury, ON, P3Y 1N2, Canada
²⁴ Department of Physics and Astronomy, Rutgers, The State University of New Jersey, 136 Frelinghuysen Road, Piscataway, NJ, 08854-8019, USA
²⁵ Department of Physics, Temple University, Philadelphia, PA, USA
²⁶ Department of Physics and Astronomy, University of California Los Angeles, 475 Portola Plaza, Los Angeles, CA, 90095-1547, USA
²⁷ Physik-Department and Excellence Cluster Universe, Technische Universität München, 85748, Garching, Germany
²⁸ Department of Physics and Laboratory for Nuclear Science, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA, 02139, USA
²⁹ SISSA/INFN, Via Bonomea 265, 34136, Trieste, Italy
³⁰ Kavli IPMU (WPI), University of Tokyo, 5-1-5 Kashiwanoha, 277-8583, Kashiwa, Japan
³¹ Center for Underground Physics, Institute for Basic Science, Daejeon, 34126, South Korea
³² Department of Physics, University of California, Irvine, Irvine, CA, 92697, USA
³³ Physikzentrum RWTH Aachen, Otto-Blumenthal-Straße, 52074, Aachen, Germany
³⁴ Department of Physics and Astronomy, State University of New York at Stony Brook, Stony Brook, NY, USA
³⁵ Department of Engineering Physics, Tsinghua University, Beijing, 100084, China
³⁶ Cornell University, Ithaca, NY, USA
³⁷ Department of Physics, University of Colorado at Boulder, Boulder, CO, USA
³⁸ Institut für Kern und Teilchenphysik, TU Dresden, Zellescher Weg 19, 01069, Dresden, Germany

^* e-mail: gorebigann@lbl.gov

Received: 18 December 2019
Accepted: 25 April 2020
Published online: 13 May 2020

Abstract

New developments in liquid scintillators, high-efficiency, fast photon detectors, and chromatic photon sorting have opened up the possibility for building a large-scale detector that can discriminate between Cherenkov and scintillation signals. Such a detector could reconstruct particle direction and species using Cherenkov light while also having the excellent energy resolution and low threshold of a scintillator detector. Situated deep underground, and utilizing new techniques in computing and reconstruction, this detector could achieve unprecedented levels of background rejection, enabling a rich physics program spanning topics in nuclear, high-energy, and astrophysics, and across a dynamic range from hundreds of keV to many GeV. The scientific program would include observations of low- and high-energy solar neutrinos, determination of neutrino mass ordering and measurement of the neutrino CP-violating phase , observations of diffuse supernova neutrinos and neutrinos from a supernova burst, sensitive searches for nucleon decay and, ultimately, a search for neutrinoless double beta decay, with sensitivity reaching the normal ordering regime of neutrino mass phase space. This paper describes Theia, a detector design that incorporates these new technologies in a practical and affordable way to accomplish the science goals described above.