We have examined consequences of strong tidal encounters between a neutron star and a normal star using SPH as a possible formation mechanism of isolated recycled pulsars in globular clusters. We have made a number of SPH simulations for close encounters between a main-sequence star of mass ranging from 0.2 to 0.7 M⊙ represented by an n=3/2 polytrope and a neutron star represented by a point mass. The outcomes of the first encounters are found to be dependent only on the dimensionless parameter n'≡ (m/(m＋M))1/2(rmin/RMS)3/2(m/M)(1/6), where m and M are the mass of the main-sequence star and the neutron star, respectively, rmin the minimum separation between two stars, and RMS the size of the main-sequence star. The material from the (at least partially) disrupted star forms a disk around the neutron star. If all material in the disk is to be acctreted onto the neutron star's surface, the mass of the disk is enough to spin up the neutron star to spin period of 1 ms.

• LEE HYUNG MOK(Department of Earth Sciences, Pusan University)
• KIM SUNG S.(nstitute for Basic Sciences, Pusan University, Department of Physics & Astronomy, University of California)
• KANG HYESUNG(Department of Earth Sciences, Pusan University)