Microscopic study of 1S0 superfluidity in dilute neutron matter

. Singlet S -wave superfluidity of dilute neutron matter is studied within the correlated BCS method, which takes into account both pairing and short-range correlations. First, the equation of state (EOS) of normal neutron matter is calculated within the Correlated Basis Function (CBF) method in the lowest cluster order using the 1 S 0 and 3 P components of the Argonne V 18 potential, assuming trial Jastrow-type correlation functions. The 1 S 0 superfluid gap is then calculated with the corresponding component of the Argonne V 18 potential and the optimally determined correlation functions. The dependence of our results on the chosen forms for the correlation functions is studied, and the role of the P -wave channel is investigated. Where comparison is meaningful, the values obtained for the 1 S 0 gap within this simplified scheme are consistent with the results of similar and more elaborate microscopic methods.