  This paper investigates the progenitors of Millisecond Pulsars (MSPs) with a
distribution of long orbital periods (P_orb > 2 d), to show the link between
white dwarf (WD) binaries and long orbits for some binary MSPs through the
Accretion Induced Collapse (AIC) of a WD. For this purpose, a model is
presented to turn binary MSPs into wide binaries and highly circular orbits (e
< 0.1) through the asymmetric kick imparted to the pulsar during the AIC
process, which may indicate a sizeable kick velocity along the rotation of the
proto-neutron star. The results show the effects of shock wave, binding energy,
and mass loss (0.2M_sun). The model shows the pulsar systems are relevant to
AIC-candidates.
