Eur. Phys. J. A (2013) 49: 92
https://doi.org/10.1140/epja/i2013-13092-9

Regular Article - Experimental Physics

Lifetime measurements of ²¹⁴Po and ²¹²Po with the CTF liquid scintillator detector at LNGS

¹⁹⁹²² Dipartimento di Fisica, Università and INFN, 20133, Milano, Italy
²⁹⁹²² Chemical Engineering Department, Princeton University, 08544, Princeton, NJ, USA
³⁹⁹²² Institut für Experimentalphysik, Universität Hamburg, Hamburg, Germany
⁴⁹⁹²² Laboratori Nazionali del Gran Sasso, INFN, 67010, Assergi, Italy
⁵⁹⁹²² Physics Department, Virginia Polytechnic Institute and State University, 24061, Blacksburg, VA, USA
⁶⁹⁹²² Physics Department, University of Massachusetts, 01003, Amherst, MA, USA
⁷⁹⁹²² Physics Department, Princeton University, 08544, Princeton, NJ, USA
⁸⁹⁹²² Dipartimento di Fisica, Università and INFN, 16146, Genova, Italy
⁹⁹⁹²² Institute of Nuclear Physics, Lomonosov Moscow State University, 119899, Moscow, Russia
¹⁰⁹⁹²² Dipartimento di Fisica, Università and INFN, I-44100, Ferrara, Italy
¹¹⁹⁹²² St. Petersburg Nuclear Physics Institute, 188350, Gatchina, Russia
¹²⁹⁹²² NRC Kurchatov Institute, 123182, Moscow, Russia
¹³⁹⁹²² Joint Institute for Nuclear Research, 141980, Dubna, Russia
¹⁴⁹⁹²² APC, Univ. Paris Diderot, CNRS/IN2P3, CEA/Irfu, Obs de Paris, Sorbonne, Paris Cité, France
¹⁵⁹⁹²² Physik Department, Technische Universität München, 85747, Garching, Germany
¹⁶⁹⁹²² Kiev Institute for Nuclear Research, 06380, Kiev, Ukraine
¹⁷⁹⁹²² Sezione di Cagliari, INFN, I-09042, Monserrato, Italy
¹⁸⁹⁹²² Max-Plank-Institut für Kernphysik, 69029, Heidelberg, Germany
¹⁹⁹⁹²² M. Smoluchowski Institute of Physics, Jagiellonian University, 30059, Krakow, Poland
²⁰⁹⁹²² Fermi National Accelerator Laboratory, 60510, Batavia, IL, USA
²¹⁹⁹²² Dipartimento di Chimica, Università and INFN, 06123, Perugia, Italy

^* e-mail: marcello.lissia@ca.infn.it

Received: 11 January 2013
Revised: 23 May 2013
Accepted: 22 June 2013
Published online: 18 July 2013

Abstract

We have studied the α-decays of ²¹⁴Po into ²¹⁰Pb and of ²¹²Po into ²⁰⁸Pb tagged by the coincidence with the preceding β-decays from ²¹⁴Bi and ²¹²Bi, respectively. The ²²²Rn, ²³²Th, and ²²⁰Rn sources used were sealed inside quartz vials and inserted in the Counting Test Facility at the underground Gran Sasso National Laboratory in Italy. We find that the mean lifetime of ²¹⁴Po is (236.00 ± 0.42(stat) ± 0.15(syst)) μs and that of ²¹²Po is (425.1 ± 0.9(stat) ± 1.2(syst)) ns. Our results, obtained from data with signal-to-background ratio larger than 1000, reduce the overall uncertainties and are compatible with previous measurements.