Eur. Phys. J. A (2014) 50: 171
https://doi.org/10.1140/epja/i2014-14171-1

Regular Article - Experimental Physics

A pair spectrometer for nuclear astrophysics experiments

¹ Division of Physics, School of Science and Technology, University of Camerino, Camerino, Italy
² Sezione di Perugia, INFN, Perugia, Italy
³ Department of Mathematics and Physics, Second University of Naples, Caserta, Italy
⁴ INFN, Sezione di Napoli, Napoli, Italy
⁵ Physics Department, University of Naples “Federico II”, Naples, Italy
⁶ Department of Physics, University of Perugia, Perugia, Italy

^* e-mail: leonardo.guerro@unicam.it

Received: 31 March 2014
Revised: 18 October 2014
Accepted: 28 October 2014
Published online: 17 November 2014

Abstract

Non-radiative transitions in nuclear capture reactions between light nuclei play a relevant role in stellar nuclear astrophysics, where nuclear processes occur at typical energies from tens to hundreds of keV. At higher energies, instead, the E0 contributions may be shadowed by more intense transitions. The experimental study of E0 transitions requires a specific detection setup, able to uniquely identify events where an electron-positron pair is produced. A compact ΔE-E charged-particle spectrometer based on two silicon detectors has been designed to be installed in the jet gas target chamber of the recoil mass separator ERNA (European Recoil separator for Nuclear Astrophysics) at the CIRCE laboratory of Caserta, Italy. The detector design, its performances and the first foreseen applications are described.