Nuclear Reactions

The Path to Improved Reaction Rates for Astrophysics

“…Using the reciprocity relations derived above allows to simplify the full reaction networks as defined in (1). Such simplifications are instructive because they enable us to study nucleosynthesis properties which are independent of details in the hydrodynamic evolution of the system or even, as shown below, independent of individual reaction rates.…”

“…193,194 Decay γ-emission of 44 Ti is observed in supernova remnants and can be used to test supernova models. 1 Furthermore, assuming incomplete isospin mixing, the strength of the neutron channel will be suppressed in comparison to the proton channel in proton-induced reactions. 185,97,187 This leads to a smaller cross section for (p,n) reactions and an increase in the cross section of (p,γ) reactions above the neutron threshold, as compared to calculations neglecting isospin (i.e.…”

“…This is similar to the decay rates introduced earlier and therefore we replaced r by λ in our notation and can include this type of reaction in the first term of Eq. (1). A similar procedure is used for electron captures by protons and nuclei.…”

“…( 2) can be generalized to three and more interacting nuclear species by integrating over the appropriate number of distributions, leading to rates r and higher order terms in Eq. (1). ) The velocity distributions in the rate definition in Eq.…”

Quasiparticle-vibration coupling effects on nuclear transitions of astrophysical interest

“…These rates have been calculated by averaging the above cross sections multiplied by the neutron velocity with Maxwell distribution (see e.g. Reference [24]). The conclusion drawn for the cross sections applies to the neutron-capture rates.…”