Optimized α/β pulse shape discrimination in Borexino

Physical review. D/Physical review. D., vol. 109

Abstract

Borexino could efficiently distinguish between α and β radiation in its liquid scintillator by the characteristic time profile of its scintillation pulse. This α/β discrimination, first demonstrated on the ton scale in the counting test facility prototype, was used throughout the lifetime of the experiment between 2007 and 2021. With this method, the α events are identified and subtracted from the solar neutrino events similar to β . This is particularly important in liquid scintillators, as the α scintillation is strongly quenched. In Borexino, the prominent Po210 decay peak was a background in the energy range of electrons scattered from Be7 solar neutrinos. Optimal α/β discrimination was achieved with a , with a higher ability to leverage the timing information of the scintillation photons detected by the photomultiplier tubes. An event-by-event, high efficiency, stable, and uniform pulse shape discrimination was essential in characterizing the spatial distribution of background in the detector. This benefited most Borexino measurements, including solar neutrinos in the pp chain and the first direct observation of the CNO cycle in the Sun. This paper presents key milestones in α/β discrimination in Borexino as a term of comparison for current and future large liquid scintillator detectors. Published by the American Physical Society 2024

Authors 74

1. D. Basilico
   Affiliation as printed

   Università degli Studi e INFN

2. G. Bellini
   Affiliation as printed

   Università degli Studi e INFN

3. Jay B. Benziger

   Princeton University

   Affiliation as printed

   Princeton University

   Chemical Engineering Department, Princeton University, Princeton, NJ 08544, USA

4. R. Biondi

   Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso

   Affiliation as printed

   INFN Laboratori Nazionali del Gran Sasso

   INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

5. B. Caccianiga
   Affiliation as printed

   Università degli Studi e INFN

6. Frank P. Calaprice

   Princeton University

   Affiliation as printed

   Princeton University

   Physics Department, Princeton University, Princeton, NJ 08544, USA

7. A. Caminata
   Affiliation as printed

   Università degli Studi e INFN

8. Alexander Chepurnov

   Lomonosov Moscow State University · Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University

   Affiliation as printed

   Lomonosov Moscow State University Skobeltsyn Institute of Nuclear Physics

   Lomonosov Moscow State University Skobeltsyn Institute of Nuclear Physics, 119234 Moscow, Russia

9. Davide D'Angelo
   Affiliation as printed

   Università degli Studi e INFN

10. A. Derbin

    Kurchatov Institute · Petersburg Nuclear Physics Institute

    Affiliation as printed

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute, 188350 Gatchina, Russia

11. Attilio Di Giacinto

    Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso

    Affiliation as printed

    INFN Laboratori Nazionali del Gran Sasso

12. V. Di Marcello

    Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso

    Affiliation as printed

    INFN Laboratori Nazionali del Gran Sasso

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

13. Xuefeng Ding

    Princeton University

    Affiliation as printed

    Princeton University

    Physics Department, Princeton University, Princeton, NJ 08544, USA

14. Antonio Di Ludovico

    Princeton University

    Affiliation as printed

    Princeton University

15. L. Di Noto
    Affiliation as printed

    Università degli Studi e INFN

16. I. Drachnev

    Kurchatov Institute · Petersburg Nuclear Physics Institute

    Affiliation as printed

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute, 188350 Gatchina, Russia

17. Davide Franco

    Centre National de la Recherche Scientifique · Université Paris Diderot

    Affiliation as printed

    CNRS

    APC (UMR_7164) - AstroParticule et Cosmologie (APC - UMR 7164, Université Paris Diderot, 10 rue Alice Domon et Léonie Duquet, case postale 7020, F-75205 Paris Cedex 13 - France)

18. C. Galbiati

    Princeton University · Gran Sasso Science Institute

    Affiliation as printed

    Gran Sasso Science Institute

    Princeton University

    Gran Sasso Science Institute, 67100 L'Aquila, Italy

    Physics Department, Princeton University, Princeton, NJ 08544, USA

19. Chiara Ghiano

    Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso

    Affiliation as printed

    INFN Laboratori Nazionali del Gran Sasso

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

20. Marco G. Giammarchi
    Affiliation as printed

    Università degli Studi e INFN

21. A. Goretti

    Princeton University

    Affiliation as printed

    Princeton University

    Physics Department, Princeton University, Princeton, NJ 08544, USA

22. Maxim Gromov

    Lomonosov Moscow State University · Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University

    Affiliation as printed

    Lomonosov Moscow State University Skobeltsyn Institute of Nuclear Physics

    Lomonosov Moscow State University Skobeltsyn Institute of Nuclear Physics, 119234 Moscow, Russia

23. Daniele Guffanti

    Johannes Gutenberg University Mainz

    Affiliation as printed

    Johannes Gutenberg-Universität Mainz

24. Aldo Ianni

    Princeton University · Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso

    Affiliation as printed

    INFN Laboratori Nazionali del Gran Sasso

    Princeton University

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

25. Andrea Ianni

    Princeton University · Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso

    Affiliation as printed

    INFN Laboratori Nazionali del Gran Sasso

    Princeton University

    Physics Department, Princeton University, Princeton, NJ 08544, USA

26. A. Jany

    Jagiellonian University

    Affiliation as printed

    Jagiellonian University

    M. Smoluchowski Institute of Physics, Jagiellonian University, 30348 Krakow, Poland

27. Vladislav Kobychev

    Institute for Nuclear Research

    Affiliation as printed

    Institute for Nuclear Research of NASU

    Institute for Nuclear Research of NASU, 03028 Kyiv, Ukraine

28. George Korga

    Royal Holloway University of London · HUN-REN Institute for Nuclear Research

    Affiliation as printed

    Institute of Nuclear Research (Atomki)

    Royal Holloway University of London

    Department of Physics, Royal Holloway University of London, Egham, Surrey,TW20 0EX, UK

    Institute of Nuclear Research (Atomki), Debrecen, Hungary

29. Sindhujha Kumaran Aachen III. Physikalisches Institut B

    Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso · Max Planck Institute for Nuclear Physics · RWTH Aachen University

    Affiliation as printed

    INFN Laboratori Nazionali del Gran Sasso

    Institut für Kernphysik

    RWTH Aachen University

    III. Physikalisches Institut B, RWTH Aachen University, 52062 Aachen, Germany

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

30. Matthias Laubenstein

    Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso

    Affiliation as printed

    INFN Laboratori Nazionali del Gran Sasso

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

31. E. A. Litvinovich

    Kurchatov Institute · National Research Nuclear University MEPhI

    Affiliation as printed

    National Research Centre Kurchatov Institute

    National Research Nuclear University MEPhI (Moscow Engineering Physics Institute)

    National Research Centre Kurchatov Institute, 123182 Moscow, Russia

    National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), 115409 Moscow, Russia

32. P. Lombardi
    Affiliation as printed

    Università degli Studi e INFN

33. I. Lomskaya

    Kurchatov Institute · Petersburg Nuclear Physics Institute

    Affiliation as printed

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute, 188350 Gatchina, Russia

34. L. Ludhová Aachen III. Physikalisches Institut B

    Max Planck Institute for Nuclear Physics · RWTH Aachen University

    Affiliation as printed

    Institut für Kernphysik

    RWTH Aachen University

    III. Physikalisches Institut B, RWTH Aachen University, 52062 Aachen, Germany

35. Igor Machulin

    Kurchatov Institute · National Research Nuclear University MEPhI

    Affiliation as printed

    National Research Centre Kurchatov Institute

    National Research Nuclear University MEPhI (Moscow Engineering Physics Institute)

    National Research Centre Kurchatov Institute, 123182 Moscow, Russia

    National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), 115409 Moscow, Russia

36. J. Martýn

    Johannes Gutenberg University Mainz

    Affiliation as printed

    Johannes Gutenberg-Universität Mainz

37. E. Meroni
    Affiliation as printed

    Università degli Studi e INFN

38. L. Miramonti
    Affiliation as printed

    Università degli Studi e INFN

39. M. Misiaszek

    Jagiellonian University

    Affiliation as printed

    Jagiellonian University

    M. Smoluchowski Institute of Physics, Jagiellonian University, 30348 Krakow, Poland

40. Valentina Muratova

    Kurchatov Institute · Petersburg Nuclear Physics Institute

    Affiliation as printed

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute, 188350 Gatchina, Russia

41. Нугманов Радик Рафаэльевич

    Kurchatov Institute

    Affiliation as printed

    National Research Centre Kurchatov Institute

    National Research Centre Kurchatov Institute, 123182 Moscow, Russia

42. L. Oberauer

    Technical University of Munich

    Affiliation as printed

    Technische Universität München

43. V. Orekhov

    Johannes Gutenberg University Mainz

    Affiliation as printed

    Johannes Gutenberg-Universität Mainz

44. F. Ortica
    Affiliation as printed

    Università degli Studi e INFN

45. Marco Pallavicini
    Affiliation as printed

    Università degli Studi e INFN

46. Luca Pelicci Aachen III. Physikalisches Institut B

    Max Planck Institute for Nuclear Physics · RWTH Aachen University

    Affiliation as printed

    Institut für Kernphysik

    RWTH Aachen University

    III. Physikalisches Institut B, RWTH Aachen University, 52062 Aachen, Germany

47. Ö. Penek

    Max Planck Institute for Nuclear Physics

    Affiliation as printed

    Institut für Kernphysik

48. Lidio Pietrofaccia

    Princeton University

    Affiliation as printed

    Princeton University

    Physics Department, Princeton University, Princeton, NJ 08544, USA

49. Nelly Pilipenko

    Kurchatov Institute · Petersburg Nuclear Physics Institute

    Affiliation as printed

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute, 188350 Gatchina, Russia

50. Andrea Pietro Pocar

    University of Massachusetts Amherst

    Affiliation as printed

    University of Massachusetts

    Amherst Center for Fundamental Interactions and Physics Department, University of Massachusetts, Amherst, MA 01003, USA

51. Georgy Raikov

    Kurchatov Institute

    Affiliation as printed

    National Research Centre Kurchatov Institute

    National Research Centre Kurchatov Institute, 123182 Moscow, Russia

52. Maria Teresa Ranalli

    Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso

    Affiliation as printed

    INFN Laboratori Nazionali del Gran Sasso

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

53. G. Ranucci
    Affiliation as printed

    Università degli Studi e INFN

54. A. Razeto

    Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso

    Affiliation as printed

    INFN Laboratori Nazionali del Gran Sasso

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

55. Alessandra Carlotta Re
    Affiliation as printed

    Università degli Studi e INFN

56. N. Rossi

    Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso

    Affiliation as printed

    INFN Laboratori Nazionali del Gran Sasso

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

57. Stefan Schönert

    Technical University of Munich

    Affiliation as printed

    Technische Universität München

58. Dmitrii Semenov

    Kurchatov Institute · Petersburg Nuclear Physics Institute

    Affiliation as printed

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute, 188350 Gatchina, Russia

59. Giulio Settanta

    Max Planck Institute for Nuclear Physics

    Affiliation as printed

    Institut für Kernphysik

60. M. Skorokhvatov

    Kurchatov Institute · National Research Nuclear University MEPhI

    Affiliation as printed

    National Research Centre Kurchatov Institute

    National Research Nuclear University MEPhI (Moscow Engineering Physics Institute)

    National Research Centre Kurchatov Institute, 123182 Moscow, Russia

    National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), 115409 Moscow, Russia

61. A. Singhal Aachen III. Physikalisches Institut B

    Max Planck Institute for Nuclear Physics · RWTH Aachen University

    Affiliation as printed

    Institut für Kernphysik

    RWTH Aachen University

    III. Physikalisches Institut B, RWTH Aachen University, 52062 Aachen, Germany

62. Oleg Smirnov

    Joint Institute for Nuclear Research

    Affiliation as printed

    Joint Institute for Nuclear Research

    Joint Institute for Nuclear Research, 141980 Dubna, Russia

63. A. Sotnikov

    University of California, Irvine · Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso · Joint Institute for Nuclear Research · Istituto Superiore per la Protezione e la Ricerca Ambientale · Institute of High Energy Physics

    Affiliation as printed

    Joint Institute for Nuclear Research

    Department of Physics and Astronomy, University of California, Irvine, California, USA

    IHEP Institute of High Energy Physics, 100049 Beijing, China

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

    Istituto Superiore per la Protezione e la Ricerca Ambientale, 00144 Roma, Italy

64. Roberto Tartaglia

    Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso

    Affiliation as printed

    INFN Laboratori Nazionali del Gran Sasso

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

65. G. Testera

    University of California, Irvine · Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso · Istituto Superiore per la Protezione e la Ricerca Ambientale · Institute of High Energy Physics

    Affiliation as printed

    Università degli Studi e INFN

    Department of Physics and Astronomy, University of California, Irvine, California, USA

    IHEP Institute of High Energy Physics, 100049 Beijing, China

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

    Istituto Superiore per la Protezione e la Ricerca Ambientale, 00144 Roma, Italy

66. E. Unzhakov

    University of California, Irvine · Kurchatov Institute · Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso · Istituto Superiore per la Protezione e la Ricerca Ambientale · Petersburg Nuclear Physics Institute

    Affiliation as printed

    St. Petersburg Nuclear Physics Institute NRC Kurchatov Institute

    Department of Physics and Astronomy, University of California, Irvine, California, USA

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

    Istituto Superiore per la Protezione e la Ricerca Ambientale, 00144 Roma, Italy

67. A. Vishneva

    University of California, Irvine · Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso · Joint Institute for Nuclear Research · Istituto Superiore per la Protezione e la Ricerca Ambientale · Institute of High Energy Physics

    Affiliation as printed

    Joint Institute for Nuclear Research

    Department of Physics and Astronomy, University of California, Irvine, California, USA

    IHEP Institute of High Energy Physics, 100049 Beijing, China

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

    Istituto Superiore per la Protezione e la Ricerca Ambientale, 00144 Roma, Italy

68. B. Vogelaar

    Virginia Tech

    Affiliation as printed

    Virginia Polytechnic Institute and State University

    Physics Department, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA

69. F. von Feilitzsch

    Technical University of Munich

    Affiliation as printed

    Technische Universität München

70. Marek Janusz Wójcik

    Jagiellonian University

    Affiliation as printed

    Jagiellonian University

    M. Smoluchowski Institute of Physics, Jagiellonian University, 30348 Krakow, Poland

71. Matthias Christian Wurm

    Johannes Gutenberg University Mainz

    Affiliation as printed

    Johannes Gutenberg-Universität Mainz

72. Sandra Zavatarelli

    University of California, Irvine · Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso · Istituto Superiore per la Protezione e la Ricerca Ambientale · Institute of High Energy Physics

    Affiliation as printed

    Università degli Studi e INFN

    Department of Physics and Astronomy, University of California, Irvine, California, USA

    IHEP Institute of High Energy Physics, 100049 Beijing, China

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

    Istituto Superiore per la Protezione e la Ricerca Ambientale, 00144 Roma, Italy

73. Kai Zuber

    Technische Universität Dresden

    Affiliation as printed

    TU Dresden

74. G. Zuzel

    Jagiellonian University · University of California, Irvine · Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso · Istituto Superiore per la Protezione e la Ricerca Ambientale · Institute of High Energy Physics

    Affiliation as printed

    Jagiellonian University

    Department of Physics and Astronomy, University of California, Irvine, California, USA

    IHEP Institute of High Energy Physics, 100049 Beijing, China

    INFN Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy

    Istituto Superiore per la Protezione e la Ricerca Ambientale, 00144 Roma, Italy