Candidate Hypervelocity Red Clump Stars in the Galactic Bulge Found Using the VVV and Gaia Surveys

We propose a new way to search for hypervelocity stars (HVS) in the Galactic bulge, by using red clump (RC) giants, that are good distance indicators. The second Gaia Data Release and the near-IR data from the VISTA Variables in the Via Lactea (VVV) Survey led to the selection of a volume limited sample of 34 bulge RC stars. A search in this combined data set leads to the discovery of seven candidate hypervelocity red clump stars in the Milky Way bulge. Based on this search we estimate the total production rate of hypervelocity RC stars from the central supermassive black hole (SMBH) to be NHVRC = 3.26 × 10−4 yr−1. This opens up the possibility of finding larger samples of HVS in the Galactic bulge using future surveys, closer to their main production site, if they originated from interactions of binaries with the central SMBH.