Simulation of a strategy for the pixel lensing of M87 using the Hubble Space Telescope




In this paper, we propose a new strategy for the pixel-lensing observations of M87 in the Virgo cluster using the Hubble Space Telescope (HST). In contrast to a previous observational strategy by Baltz et al., we show that a few days of intensive observations with the duration of ∼90 min in each HST orbit will increase the observational efficiency of high-magnification events by more than one order of magnitude. We perform a Monte Carlo simulation for this strategy and we show that the number of high-magnification microlensing events will increase at the rate of 4.2 events per day with a typical transit time-scale of 16 h. We also examine the possibility of observing mini-halo dark matter structures using pixel lensing.