skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: AN UPDATED {sup 6}Li(p, {alpha}){sup 3}He REACTION RATE AT ASTROPHYSICAL ENERGIES WITH THE TROJAN HORSE METHOD

Journal Article · · Astrophysical Journal
; ;  [1]; ; ;  [2]; ; ;  [3];  [4]
  1. Dipartimento di Fisica e Astronomia, Universita di Catania, I-95123 Catania (Italy)
  2. INFN-Laboratori Nazionali del Sud, I-95125 Catania (Italy)
  3. Dipartimento di Fisica, Universita di Pisa, I-56127 Pisa (Italy)
  4. Dipartimento di Fisica e Scienze della Terra, Universita di Ferrara, I-44100 Ferrara (Italy)

The lithium problem influencing primordial and stellar nucleosynthesis is one of the most interesting unsolved issues in astrophysics. {sup 6}Li is the most fragile of lithium's stable isotopes and is largely destroyed in most stars during the pre-main-sequence (PMS) phase. For these stars, the convective envelope easily reaches, at least at its bottom, the relatively low {sup 6}Li ignition temperature. Thus, gaining an understanding of {sup 6}Li depletion also gives hints about the extent of convective regions. For this reason, charged-particle-induced reactions in lithium have been the subject of several studies. Low-energy extrapolations of these studies provide information about both the zero-energy astrophysical S(E) factor and the electron screening potential, U{sub e} . Thanks to recent direct measurements, new estimates of the {sup 6}Li(p, {alpha}){sup 3}He bare-nucleus S(E) factor and the corresponding U{sub e} value have been obtained by applying the Trojan Horse method to the {sup 2}H({sup 6}Li, {alpha} {sup 3}He)n reaction in quasi-free kinematics. The calculated reaction rate covers the temperature window 0.01 to 2T{sub 9} and its impact on the surface lithium depletion in PMS models with different masses and metallicities has been evaluated in detail by adopting an updated version of the FRANEC evolutionary code.

OSTI ID:
22126822
Journal Information:
Astrophysical Journal, Vol. 768, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
Country of Publication:
United States
Language:
English