Cores of globular clusters are an ideal place for close encounters between stars. The outcome of tidal capture can be stellar mergers, close binaries between normal stars (W UMa type), cataclysmic variables composed of white dwarf and normal star pairs, or low-mass X-ray binaries consisting of a neutron star and a normal star pairs. Stellar mergers can be the origin of blue stragglers in dense globular clusters although they are hard to observe. Low mass X-ray binaries would eventually become binary pulsars with short pulse periods after the neutron stars accrete sufficient amount of matter from the companion. However, large number of recently discovered, isolated millisecond pulsars (as opposed to binary pulsars) in globular clusters may imply that they do not have to gain angular speeds during the X-ray binary phase. We propose that these isolated millisecond pulsars may have formed through the disruptive encounters, which lead to the formation of accretion disk without Roche lobe filling companion, between a neutron star and a main-sequence star. Based on recently developed multicomponent models for the dynamical evolution of globular clusters, we compute the expected numbers of various systems formed by tidal capture as a function of time.

In this review paper we explain the following gamma-ray emission features from the millisecond pulsars. (1) Why is the dipolar field of millisecond pulsars so weak but the magnetic pair creation process may still be able to control the size of the outergap? (2) A sub-GeV pulse component could occur in the vicinity of the radio pulse of millisecond pulsars. (3) Orbital modulated gamma-rays should exist in the black widow systems for large viewing angle.