No-core shell model calculations of the photonuclear cross section of 10B

. Results of ab initio no-core, shell model calculations for the photonuclear cross section of 10 B are presented using realistic two-nucleon (NN) chiral forces up to next-to-next-to-next-order (N3LO) softened by the similarity renormalization group method (SRG) with λ = 2 . 02 fm -1 . The electric-dipole response function is calculated using the Lanczos method, with the effects of the continuum included via neutron escape widths derived from R-matrix theory and using the Lorentz integral transform method. The calculated cross section agrees well with experimental data in terms of structure as well as in absolute peak height, σ max = 4 . 85 mb at photon energy ω = 23 . 61 MeV, and integrated cross section 85.36 MeV . mb. We also test the Brink hypothesis by calculating the electric-dipole response for the first nine positive-parity states with J ≠ 0 in 10 B and verify that dipole excitations built upon the ground and excited states have similar characteristics.