The 13.645 MeV state in20Ne

UPDATED THM ASTROPHYSICAL FACTOR OF THE $^{19}{\rm F}{{(p,\alpha )}^{16}}{\rm O}$ REACTION AND INFLUENCE OF NEW DIRECT DATA AT ASTROPHYSICAL ENERGIES

“…astrophysical factor is due to the emission of α particles from Ne 20 leaving O 16 in its ground state (referred to as α 0 , Spyrou et al 2000); in what follows, we will focus on this channel. Widely adopted compilations such as the Nuclear Astrophysics Compilation of Reaction Rates (NACRE, Angulo et al 1999) used data from different sources to supply a recommended astrophysical factor and, consequently, reaction rate Breuer 1959;Warsh et al 1963;Morita et al 1966;Caracciolo et al 1974;Cuzzocrea et al 1980). However, the lowest-energy data reach a 461 keV center-of-mass energy (Breuer 1959), well above the Gamow peak, and only the unpublished data of Lorentz-Wirzba (1978), which have been used in Herndl et al (1991) and Yamashita & Kudo (1993), partially cover the relevant astrophysical range.…”

Investigation of the19F(p, α)16O reaction in the THM framework

“…In the NACRE compilation [16], containing the most recent cross-section measurements, the recommended 19 F(p, α 0 ) 16 O astrophysical S(E)-factor, which is the dominant channel at astrophysical energies, was obtained from several works [15,22,14,23,13,24], with the lowest-energy direct data reaching 461 keV center-of-mass energy [15]. The Gamow window is only partially covered by the unpublished data of [18], which have been used in [19,20] to evaluate the astrophysical factor in the zeroand finite-range DWBA approaches, respectively.…”

“…6 MeV, the reduced partial widths are obtained through a R-matrix fit of the available direct data (black stars [13], blue squares [14], green triangles [15]). Below 0.6 MeV, the resonance parameters are obtained from the modified R-matrix fit of the d 2 σ/dE cm dΩ n TH cross section, normalized to the direct data in the 0.6 − 0.9 MeV range.…”

Preliminary results for the19F(ρ,α)16O reaction cross section measured at INFN-LNS

“…S-factor of the 19 F(p,α) 16 O reaction available in literature [4]. The full and empty blue circles are from Lombardo et al [4], the black triangles show the data of Breuer et al [5], the green stars the data of Isoya et al [6] and the empty diamonds the data of Caracciolo et al [7]. The red line represents the results of the R-matrix calculation based on THM measurement, as reported in Indelicato et al [8].…”