Early warning search for LISA massive black holes*

The space based laser interferometer LISA, expected to be operational in the next decades, will be able to probe the millihertz frequency band. This will make it sensitive to a vast array of compact object mergers, including the massive black holes or MBHs. These black holes, straddling the intermediate and supermassive types of black holes, have masses extending above a minimum of 1000 solar mass. They are expected to be observable within the LISA band for several weeks to months before they merge. This makes them excellent candidates for low latency, pre-merger observations. Also, some mergers of MBHs are expected to have electromagnetic counterparts due to the presence of gas or disks. Pre-merger alerts with sky location information from LISA data analysis sent out to the astronomy community, would enable early detections of such mergers in multiple electromagnetic bands. Such multimessenger observations stand to further our knowledge of astrophysics, including that of black hole formation and evolution. In my talk we explore the possibility of sending out such pre-merger alerts, using a simulated LISA training data set.