Eur. Phys. J. C (2004) 37: 421-431
https://doi.org/10.1140/epjc/s2004-01991-1

experimental physics

New experimental limits on violations of the Pauli exclusion principle obtained with the Borexino Counting Test Facility

¹ Physics Department, Virginia Polytechnic Institute and State University, Robeson Hall, VA 24061-0435, Blacksburg, USA
² I.N.F.N Laboratori Nazionali del Gran Sasso, SS 17 bis Km 18+910, 67010, Assergi(AQ), Italy
³ Dipartimento di Fisica Nucleare e Teorica Universita’ and I.N.F.N., Via A. Bassi 6, 27100, Pavia, Italy
⁴ Laboratoire de Physique Corpusculaire et Cosmologie, 11 place Marcelin, Berthelot, 75231, Paris Cedex 05, France
⁵ Dipartimento di Fisica Universitá and I.N.F.N., Via Celoria 16, 20133, Milano, Italy
⁶ Dept. of Physics, Princeton University, Jadwin Hall, Washington Rd, NJ 08544-0708, Princeton, USA
⁷ Max-Planck-Institut fuer Kernphysik, Postfach 103 980, 69029, Heidelberg, Germany
⁸ Dept. of Physics, Queen’s University Stirling Hall, K7L 3N6, Kingston, Ontario, Canada
⁹ Technische Universitaet Muenchen, James Franck Strasse E15, 85747, Garching, Germany
¹⁰ Joint Institute for Nuclear Research, 141980, Dubna, Russia
¹¹ Dept. of Physics Massachusetts Institute of Technology, MA 02139, Cambridge, USA
¹² Dipartimento di Chimica, Universitá, Perugia, Via Elce di Sotto 8, 06123, Perugia, Italy
¹³ RRC Kurchatov Institute, Kurchatov Sq. 1, 123182, Moscow, Russia
¹⁴ Dipartimento di Fisica Universitá and I.N.F.N., Genova, Via Dodecaneso 33, 16146, Genova, Italy
¹⁵ KFKI-RMKI, Konkoly Thege ut 29-33, 1121, Budapest, Hungary
¹⁶ Bell Laboratories, Lucent Technologies, NJ 07974-2070, Murray Hill, USA
¹⁷ M .Smoluchowski Institute of Physics, Jagellonian University, 30059, Krakow, Poland

^* e-mail: derbin@mail.pnpi.spb.ru

Abstract

The Pauli exclusion principle (PEP) has been tested for nucleons (n,p) in and nuclei, using the results of background measurements with the prototype of the Borexino detector, the Counting Test Facility (CTF). The approach consisted of a search for , n, p and/or ’s emitted in a non-Paulian transition of 1P- shell nucleons to the filled 1S _1/2 shell in nuclei. Similarly, the Pauli-forbidden decay processes were searched for. Due to the extremely low background and the large mass (4.2 tons) of the CTF detector, the following most stringent up-to-date experimental bounds on PEP violating transitions of nucleons have been established: , , , , and , all at C.L.