Properties of the first excited state of 9Be derived from (gamma,n) and (e,e') reactions

Abstract

Properties of the first excited state of the nucleus 9Be are discussed based on recent (e,e') and (gamma,n) experiments. The parameters of an R-matrix analysis of different data sets are consistent with a resonance rather than a virtual state predicted by some model calculations. The energy and the width of the resonance are deduced. Their values are rather similar for all data sets, and the energy proves to be negative. It is argued that the disagreement between the extracted B(E1) values may stem from different ways of integration of the resonance. If corrected, fair agreement between the (e,e') and one of the (gamma,n) data sets is found. A recent (gamma,n) experiment at the HIgS facility exhibits larger cross sections close to the neutron threshold which remain to be explained.

5 pages, accepted fro publication in Phys. Rev. C

References in corpus (3)

• Cross Section Measurement of 9Be(γ,n)8Be and Implications for α+α+n -> 9Be in the r-Process
• Resonance parameters of the first 1/2+ state in 9Be and astrophysical implications
• Measurements of the 48Ca(γ,n) Reaction

Cited by in corpus (6)

• Unified ab initio approaches to nuclear structure and reactions
• Continuum and Three-Nucleon Force Effects on 9Be Energy Levels
• Isovector and isoscalar dipole excitations in ${}^9$Be and ${}^{10}$Be studied with antisymmetrized molecular dynamics
• Photodisintegration cross section of ${}^9$Be up to 16 MeV in the $\alpha$ + $\alpha$ + n three-body model
• Formation and decay of resonance state in ${}^9$Be and ${}^9$B nuclei. Microscopic three-cluster model investigations
• A reanalysis of radioisotope measurements of the ${}^9$Be$(\gamma ,n{)}^8$Be cross-section