First Measurement of the 19F( , p)22Ne Reaction at Energies of Astrophysical Relevance

First Measurement of the 19F( , p)22Ne Reaction at Energies of Astrophysical Relevance

The observational 19F abundance in stellar environments systematically exceeds the predicted one, thus representing one of the unsolved challenges for stellar modeling. It is therefore clear that further investigation is needed in this field. In this work, we focus our attention on the measurement o...

Full description

Saved in:
Bibliographic Details
Published in:The Astrophysical journal Vol. 836; no. 1
Main Authors: Pizzone, R. G., D'Agata, G., Cognata, M. La, Indelicato, I., Spitaleri, C., Blagus, S., Cherubini, S., Figuera, P., Grassi, L., Guardo, G. L., Gulino, M., Hayakawa, S., Kshetri, R., Lamia, L., Lattuada, M., Mijatovi, T., Milin, M., Miljani D., ., Prepolec, L., Rapisarda, G. G., Romano, S., Sergi, M. L., Skukan, N., Soi, N., Toki, V., Tumino, A., Uroi, M.
Format: Journal Article
Language:English
Published: Philadelphia The American Astronomical Society 10-02-2017
IOP Publishing
Subjects:
Astronomical models
Astrophysics
Electron beams
nuclear reactions, nucleosynthesis, abundances
Stellar models
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The observational 19F abundance in stellar environments systematically exceeds the predicted one, thus representing one of the unsolved challenges for stellar modeling. It is therefore clear that further investigation is needed in this field. In this work, we focus our attention on the measurement of the reaction in the astrophysical energy range, between 0.2 and 0.8 MeV (far below the Coulomb barrier, 3.8 MeV), as it represents the main destruction channel in He-rich environments. The lowest energy at which this reaction has been studied with direct measurements is ∼0.66 MeV, covering only the upper tail of the Gamow window, causing the reaction-rate evaluation to be based on extrapolation. To investigate lower energies, the reaction has been studied by means of the Trojan horse method, applied to the quasi-free reaction at Ebeam = 6 MeV. The indirect cross section of the reaction at energies 1 MeV was extracted, fully covering the astrophysical region of interest and overlapping existing direct data for normalization. Several resonances have been detected for the first time inside the Gamow window. The reaction rate has been calculated, showing an increase up to a factor of 4 with respect to the literature at astrophysical temperatures. This might lead to potential major astrophysical implications.
Bibliography:Stars and Stellar Physics
AAS03918
ISSN:0004-637X
1538-4357
DOI:10.3847/1538-4357/836/1/57