Further explorations of Skyrme-Hartree-Fock-Bogoliubov mass formulas. II. Role of the effective mass

Abstract

We have constructed four new complete mass tables, referred to as HFB-4 to HFB-7, each one including all the 9200 nuclei lying between the two drip lines over the range of Z and N ≥ 8 and Z ≤ 120. HFB-4 and HFB-5 have the isoscalar effective mass M * s constrained to the value 0.92M , with the former having a density-independent pairing, and the latter a density-dependent pairing.

Microscopic HFB + QRPA predictions of dipole strength for astrophysics applications

“…Are also included in Table 1 the effective isoscalar (M * s ), isovector (M * v ) nucleon mass and the rootmean-square (rms) deviations σ between the measured and estimated masses for the 2135 nuclei with Z, N ≥ 8. More details about these forces can be found in [18][19][20]. The major differences between these six forces are found in the density-dependence of the pairing force and the adopted isoscalar effective nucleon mass.…”

“…The HFB calculations considered in the present work are fully detailed in [17][18][19][20]. They are based on the conventional Skyrme force of the form…”

“…Nuclear forces are traditionally determined by fitting such ground state properties for less than ten or so nuclei. Recently, progress has been achieved in determining the Skyrme force by fitting essentially all the mass data [17][18][19][20]. The only excited feature taken into account so far was the giant monopolar resonance energy [31] in order to predict the infinite matter compressibility modulus.…”

“…Based on this Skyrme-HFB approach, a number of effective forces have been determined recently [18][19][20], the parameters of the underlying forces being fitted exclusively to all the 2135 available experimental masses [22], with some additional constraints regarding the stability of neutron matter and the incompressibility of nuclear matter. The parameters corresponding to these six forces named BSk2-BSk7 are summarized in Table 1.…”

“…The pairing force acting between like nucleons is treated in the full Bogoliubov framework with a δ-function pairing force of the form [19][20][21] …”