Mk. Cheoun et al., TOTAL GAMOW-TELLER STRENGTH, GROUND-STATE CORRELATIONS AND SUM-RULES IN QRPA WITH NEUTRON-PROTON PAIRING, Nuclear physics. A, 587(2), 1995, pp. 301-317
The sum of the Gamow-Teller (GT) strength in 1p0f shell nuclei is inve
stigated by the Quasi-particle Random Phase Approximation (QRPA), wher
e BCS and RPA ground-state correlations are included with proton-proto
n and neutron-neutron but in addition also with neutron-proton (np) pa
iring correlations. Two sums of GT strength with and without closure f
or the intermediate excited states are derived including different app
roaches for the ground-state correlations. The sum of the GT strength
is compared to the available experimental data and other theoretical c
alculations. The total GT strength in the usual BCS scheme is reduced
by additional neutron-proton (np) pairing correlations. The usual RPA
ground-state correlations reduce the total GT strength estimated from
the BCS approximation while RPA with np pairing correlations yields an
appreciably smaller reduction. Finally, ground-state correlations bey
ond RPA are also shown to reduce the total GT strength.