Quenching of pairing gap at finite temperature in 184W

We extract pairing gap in ${}^{184}$W at finite temperature for the first time from the experimental level densities of ${}^{183}$W, ${}^{184}$W, and ${}^{185}$W using “thermal” odd-even mass difference. We found the quenching of pairing gap near the critical temperature $T_c=0.47$ MeV in the BCS calculations. It is shown that the monopole pairing model with a deformed Woods-Saxon potential explains the reduction of the pairing correlation using the partition function with the number parity projection in the static path approximation plus random-phase approximation.