出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We estimate the rate of near-eld microlensing events expected from all-sky surveys and investigate
the properties of the events. Under the assumption that lenses are composed of stars, our
estimation of the event rate ranges from Gtot 0:1 yr1 for a survey with a magnitude limit of
Vlim = 12 to Gtot 23 yr1 for a survey with Vlim = 18. We nd that the average distances to
the source star and lens vary considerably depending on the magnitude limit, while the dependencies
of the event time scale and lens-source transverse speed are weak. We also nd that the
the average lens-source proper motion of events expected from a survey with Vlim = 18 would
be hmi & 40 mas yr1 and the value further increases as the magnitude limit becomes lower, implying
that the source and lens of a signicant fraction of near-eld events can be resolved from
high-resolution follow-up observations conducted several years after the lensing magnication.
