SMI – STEFAN MEYER INSTITUTE VIP2 at Gran Sasso – Test of the validity of the spin statistics theorem for electrons with X-ray spectroscopy Johann Marton for the VIP2 Collaboration https://www.lngs.infn.it/en/pagine/vip-eng WWW:OEAW.AC.AT/SMI

VIP-2 Collaboration ITALY INFN laboratori Nazionali di Frascati: C. Curceanu, S. Bartalucci, A. Clozza, L. de Paolis, A. d’Uffizi, C. Guaraldo, M. Iliescu, K. Piscicchia(*), E. Sbardella, A. Scordo, H. Shi, D. Sirghi, F. Sirghi, L.Sperandio  (*) and Museo torico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, Roma INFN Laboratori Nazionali del Gran Sasso: M. Laubenstein Università and INFN Trieste: E. Milotti   AUSTRIA SMI-Vienna: C. Berucci, M. Cargnelli, J. Marton, A. Pichler, J. Zmeskal FRANCE Univ. Rennes: S. di Matteo GERMANY TUM-Muenchen: O. Vazquez Doce ROMANIA IFIN-HH, Bucharest: M. Bragadireanu, D. Pietreanu, T. Ponta SWITZERLAND CERN: S. Bertolucci Univ. Neuchatel: J.-P. Egger

SMI – STEFAN MEYER INSTITUTE Motivation If something in fundamental physics can be tested, then it absolutely must be tested (L. Okun) PEP a solid rule of nature but no intuitive explanation (Pauli) PEP connected with spin statistics Spin statistics connection is a very robust feature of quantum field theory Nature is divided in fermions and bosons VIP/VIP-2 idea: testing PEP for electrons employing the method of Ramberg-Snow with detectors successfully used in kaonic atom spectroscopy (x-ray detector arrays, CCDs, SDDs) WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE 1925 "In an atom there cannot be two or more equivalent electrons for which the values of all four quantum numbers coincide. If an electron exists in an atom for which all of these numbers have definite values, then the state is occupied." W.Pauli, Über den Zusammenhang des Abschlusses der Elektronengruppen im Atom mit der Komplexstruktur der Spektren, Zeitschrift für Physik 31 (1925) 765. WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE Consequences Some examples: Periodic table of the elements Stability of matter Neutron stars …… etc So far no violation of the spin-statistics could be found - but violations can arise in string theory WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE WWW:OEAW.AC.AT/SMI

Why the Special interest in the leptonic sector ? Violation of the spin-statistics relation would have an important impact not only on microscopic atomic, nuclear, and particle physics scales, but also induce very interesting effects at astronomically large scales. In particular, it was argued that spin-statictics relation for neutrinos could be strongly violated, If so, neutrino may be the sole dark matter particle, contributing both to hot and cold dark matter. There are speculations concerning a bosonic component of neutrinos with severe cosmological consequences (A. Dolgov et al.)

SMI – STEFAN MEYER INSTITUTE WWW:OEAW.AC.AT/SMI

Best Limits for PEP Violation SMI – STEFAN MEYER INSTITUTE Best Limits for PEP Violation WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE VIP2 Experiment in LNGS Running since 2016 WWW:OEAW.AC.AT/SMI

VIP2 Installation at LNGS

SMI – STEFAN MEYER INSTITUTE WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE VIP-2 Data taking in2016 I = 100 A I = 0 A WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE Toward the final result With first VIP2 data taking 2016 same sensitivity like VIP in 3 years C. Curceanu et al. arXiv:1705.0265[quant-ph] WWW:OEAW.AC.AT/SMI

SMI – STEFAN MEYER INSTITUTE Future Research Plan Installation of part of the passive shielding New SDD detector system with new copper target Optimized shielding with data taking of about 3 years (i.e. approx. 2020) Goal after 3 years data taking with and without current  102 improvement of VIP limit WWW:OEAW.AC.AT/SMI

Thank you for your attention SMI – STEFAN MEYER INSTITUTE "The special place enjoyed by the Pauli principle in modern theoretical physics does not mean that this principle does not require further and exhaustive experimental tests. On the contrary, it is specifically the fundamental nature of the Pauli principle which would make such tests, over the entire periodic table, of special interest." Lev Okun 1929-2015 Thank you for your attention WWW:OEAW.AC.AT/SMI

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