  To overcome the high optical extinction, near-infrared observations are
needed for probing the microlensing events toward the Galactic center. The
2015-2019 UKIRT microlensing survey toward the Galactic center is the first
dedicated precursor near-infrared (NIR) survey for the Nancy Grace Roman Space
Telescope. We here analyze the online data from the UKIRT microlensing survey,
reaching $l=b=0^\circ$. Using the event-finder algorithm of KMTNet with the
$\Delta \chi^2$ threshold of 250, we find 522 clear events, 436 possible
events, and 27 possible anomalous events. We fit a point-source point-lens
(PSPL) model to all the clear events and derive the PSPL parameters with
uncertainties using a Markov chain Monte Carlo method. Assuming perfect
detection efficiency, we compute the uncorrected event rates, which should
serve as the lower limits on the true event rate. We find that the uncorrected
NIR event rates are likely rising toward the Galactic center and higher than
the optical event rates.
