Search for double- decays of 96Ru and 104Ru by ultra-low background HPGe spectrometry

P. Belli; R. Bernabei; F. Cappella; R. Cerulli; F. A. Danevich; S. d’Angelo; A. Incicchitti; M. Laubenstein; O. G. Polischuk; D. Prosperi; V. I. Tretyak

doi:10.1140/epja/i2009-10867-5

2022 Impact factor 2.7

Hadrons and Nuclei

Eur. Phys. J. A (2009) 42: 171-177
https://doi.org/10.1140/epja/i2009-10867-5

Regular Article - Experimental Physics

Search for double- decays of ⁹⁶Ru and ¹⁰⁴Ru by ultra-low background HPGe spectrometry

P. Belli¹, R. Bernabei¹^*, F. Cappella², R. Cerulli³, F. A. Danevich⁴, S. d’Angelo¹, A. Incicchitti², M. Laubenstein³, O. G. Polischuk⁴, D. Prosperi² and V. I. Tretyak⁴

¹ Dipartimento di Fisica, Università di Roma “Tor Vergata” and INFN, Sezione di Roma “Tor Vergata”, I-00133, Roma, Italy
² Dipartimento di Fisica, Università di Roma “La Sapienza” and INFN, Sezione di Roma, I-00185, Roma, Italy
³ INFN, Laboratori Nazionali del Gran Sasso, I-67010, Assergi (Aq), Italy
⁴ Institute for Nuclear Research, MSP 03680, Kyiv, Ukraine

^* e-mail: rita.bernabei@roma2.infn.it

Received: 25 June 2009
Revised: 5 August 2009
Accepted: 28 August 2009
Published online: 2 October 2009

Abstract

A search for double- processes in ⁹⁶Ru and ¹⁰⁴Ru was realized in the underground Gran Sasso National Laboratories of the INFN (Italy) with the help of ultra-low background HPGe spectrometry. After 158h of data taking with 473g ruthenium sample, new improved limits on double-beta processes in ⁹⁶Ru have been established on the level of 10¹⁸-10¹⁹yr. For the first time the double-beta decay of ¹⁰⁴Ru to the 2⁺ ₁ excited level of ¹⁰⁴Pd has been restricted as T _1/2 > 3.5×10¹⁹ yr.