Search for 22Na in novae supported by a novel method for measuring femtosecond nuclear lifetimes
Chloé Fougères, F. de Oliveira Santos, J. José, C. Michelagnoli, E. Clément, Y. H. Kim, A. Lemasson, V. Guimarães, D. Barrientos, D. Bemmerer, G. Benzoni, A. J. Boston, Roman Böttger, F. Boulay, A. Bracco, Igor Čelikovíć, B. Cederwall, M. Ciemała, C. Delafosse, C. Domingo-Pardo, J. Dudouet, J. Eberth, Z. Fulop, V. González, Andrea Gottardo, Johan Goupil, Herbert Hess, Andrea Jungclaus, Ayşe Kaşkaş, Amel Korichi, Silvia M. Lenzi, H. Li, Hongjie Li, Joa Ljungvall, Araceli Lopez-Martens, Roberto Menegazzo, Daniele Mengoni, Benedicte Million, Jaromír Mrázek, Daniel R. Napoli, Alahari Navin, Johan Nyberg, Zsolt Podolyák, Alberto Pullia, Begoña Quintana, Damien Ralet, Nadine Redon, Peter Reiter, Kseniia Rezynkina, Frédéric Saillant, Marie-Delphine Salsac, Angel M. Sánchez-Benítez, Enrique Sanchis, Menekşe Şenyiğit, Marco Siciliano, Nadezda A. Smirnova, Dorottya Sohler, Mihai Stanoiu, Christophe Theisen, Jose J. Valiente-Dobón, Predrag Ujić, Magdalena Zielińska
Abstract
Abstract Classical novae are thermonuclear explosions in stellar binary systems, and important sources of 26 Al and 22 Na. While γ rays from the decay of the former radioisotope have been observed throughout the Galaxy, 22 Na remains untraceable. Its half-life (2.6 yr) would allow the observation of its 1.275 MeV γ -ray line from a cosmic source. However, the prediction of such an observation requires good knowledge of its nucleosynthesis. The 22 Na( p , γ ) 23 Mg reaction remains the only source of large uncertainty about the amount of 22 Na ejected. Its rate is dominated by a single resonance on the short-lived state at 7785.0(7) keV in 23 Mg. Here, we propose a combined analysis of particle-particle correlations and velocity-difference profiles to measure femtosecond nuclear lifetimes. The application of this method to the study of the 23 Mg states, places strong limits on the amount of 22 Na produced in novae and constrains its detectability with future space-borne observatories.