Calculation of the Thomas-Ehrman shift in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi mathvariant="normal">F</mml:mi><mml:mprescripts/><mml:none/><mml:mn>16</mml:mn></mml:mmultiscripts></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mmultiscripts><mml:mi mathvariant="normal">O</mml:mi><mml:mprescripts/><mml:none/><mml:mn>15</mml:mn></mml:mmultiscripts><mml:mo>(</mml:mo><mml:mi>p</mml:mi><mml:mo>,</mml:mo><mml:mi>p</mml:mi><mml:mo>)</mml:mo></mml:mrow></mml:math> cross sections within the Gamow shell model
N. Michel, J. G. Li, L. H. Ru, W. Zuo
Abstract
The $^{16}\mathrm{F}$ nucleus is situated at the proton drip line and is unbound by proton emission by only about 500 keV. Continuum coupling is then prominent in this nucleus. Added to that, its low-lying spectrum consists of narrow proton resonances as well. It is therefore a very good candidate to study nuclear structure and reactions at the proton drip line. The low-lying spectrum and scattering proton-proton cross section of $^{16}\mathrm{F}$ were calculated with the coupled-channels Gamow shell model framework in this case using an effective Hamiltonian. Experimental data are very well reproduced, as were those of its mirror nucleus $^{16}\mathrm{N}$. Isospin-symmetry breaking generated by the Coulomb interaction and continuum coupling explicitly appears in our calculations. In particular, the different continuum couplings in $^{16}\mathrm{F}$ and $^{16}\mathrm{N}$ involving ${s}_{1/2}$ partial waves allow one to explain the different ordering of low-lying states in their spectra.