The bottleneck of CNO burning and the age of Globular Clusters

¹ INAF-Osservatorio Astronomico di Collurania, Italy
² INFN-sezione di Napoli, Complesso Universitario di Monte Sant'Angelo, Via Cintia, ed. G80126 Napoli, Italy
³ Dipartimento di Scienze Fisiche, Universitá Federico II, Complesso Universitario di Monte Sant'Angelo, Via Cintia, ed. G80126 Napoli, Italy
⁴ Universitá di Genova, Dipartimento di Fisica and INFN, Genova, Italy
⁵ Ruhr Universität Bochum, Bochum, Germany
⁶ INFN Laboratori Nazionali del Gran Sasso, Assergi, Italy
⁷ Institut für Atomare Physik und Fachdidaktik, Technische Universität Berlin
⁸ Universitá di Milano, Istituto di Fisica Generale Applicata and INFN, Milano, Italy
⁹ INFN-sezione di Padova, Italy
¹⁰ Centro de Fisica Nuclear da Universidade de Lisboa, Lisboa, Portugal
¹¹ Atomki, Debrecen, Hungary
¹² Universitá di Torino, Dipartimento di Fisica Sperimentale and INFN, Torino, Italy
¹³ Seconda Universitá di Napoli, Dipartimento di Scienze Ambientali, Caserta, and INFN, Napoli, Italy
¹⁴ Universitá di Padova, Dipartimento di Fisica, Padova and INFN Legnaro, Italy

Corresponding author: G. Imbriani, imbriani@na.infn.it

Received: 6 January 2004
Accepted: 1 March 2004

Abstract

The transition between the Main Sequence and the Red Giant Branch in low mass stars is powered by the onset of CNO burning, whose bottleneck is ¹⁴N(p, O. The LUNA collaboration has recently improved the low energy measurements of the cross section of this key reaction. We analyse the impact of the revised reaction rate on the estimate of the Globular Cluster ages, as derived from the turnoff luminosity. We found that the age of the oldest Globular Clusters should be increased by about 0.7-1 Gyr with respect to the current estimates.