The detecting efficiency of Coulomb dissociation fragments by a givendetector-array placed at very forward angle has been calculated by usingMonte--Carlo simulation based on a semi-classic description of the Coulombdissociation 50MeV/u 208Na+
2208Pb-p + 19Ne + 208Pb. The feasibility of measuring theresonance cross section of the capture reaction p+ 19Ne~20Na in stellar environmentwas discussed.