17O hydrogen burning at the energies of classical nova at LUNA

Abstract

Hydrogen burning of 17 O sensitively influences nucleosynthesis in a number of stellar sites, including red giants, asymptotic giant branch (AGB) stars, massive stars, and classical novae. In particular, the ratio between reaction rates of 17 O(p,α) 14 N (Q = 1.2 MeV) and 17 O(p,γ) 18 F (Q = 5.6 MeV) channels on 17 O is one of the most important parameters for the galactic synthesis of 17 O, the stellar production of radioactive 18 F, and for predicted O isotopic ratios in presolar grains. The LUNA collaboration has studied the 17 O(p,γ) 18 F in a wide energy range (from 167 up to 360 keV) covering completely the energy of the nova scenario and the new results reduce by a factor of 4 the precedent evaluation of the 17 O(p,γ) 18 F reaction rate. In addition, the 183.3 keV resonance strength has been determined with unprecedented precision solving the discrepancies of previous experimental efforts.