NewCl34proton-threshold states and the thermonuclearS33

Constraining nova observables: Direct measurements of resonance strengths in33S(p,γ)34Fallis1, Parikh2, Bertone3 et al. 2013Phys. Rev. CSelf Cite16180View full textAdd to dashboardCite

“…More recent work by Parikh et al [10] reports the existence of six new states in 34 Cl located within the Gamow window for ONe nova peak temperatures (between 0.2 and 0.4 GK, E r = 185-555 keV). These states have the potential to significantly increase the 33 S(p,γ ) 34 Cl rate, depending on their resonance strengths.…”

“…The result of the latter study was a calculated factor of 150 overproduction of 33 S compared to solar. However, this may vary between ≈1.5 and 450 due to estimated experimental uncertainties [10]. Data for the 33 S(p,γ ) 34 Cl reaction were taken from a complilation by Endt [11] and included resonance strength measurements by Waanders et al [12] down to a resonance energy of E r = 432 keV.…”

“…These states have the potential to significantly increase the 33 S(p,γ ) 34 Cl rate, depending on their resonance strengths. Based on a recommended rate, which is the geometric mean of the rate from only the known resonance strengths and the maximal theoretical contribution from the states with no resonance strength information, a reduction by a factor of 12 from the 33 S abundance from the José et al [9] value was estimated [10]. The goal of this work is to measure resonance strengths or at least determine sufficiently restrictive upper limits of the as-yet-unmeasured states relevant to ONe novae nucleosynthesis.…”

Discovery of34g,mCl(p,γ)35Arresonances activated at classical nova temperatures

“…Most of these grains are condensed in the outflows of AGB stars and supernovae [7]. Current nova grain candidates have low 12 C/ 13 C and 14 N/ 15 N ratios, 30 Si excesses, and close to solar 28 Si/ 29 Si ratios [6,8]. However, these signatures do not eliminate the possibility that some of these grains were produced in supernovae, and further isotopic signatures would help to distinguish between nova and supernova origins [9,10].…”

“…Recent experimental [10,[12][13][14] and modeling [10] work has been done to constrain the expected 32 S/ 33 S ratio for nova grains to a range of 110-130, which distinguishes it from the supernova predictions. However, this value is consistent with the solar isotopic ratio, and therefore it would need to be measured alongside the 32 S/ 34 S isotopic ratio and/or ratios for other elements to identify nova grains.…”