KEY PROJECT: THE DETECTION AND MONITORING OF ELECTROMAGNETIC COUNTERPARTS OF GRAVITATIONAL WAVE SOURCES WITH SWIFT IN O3

WE SEEK TO IDENTIFY AND FOLLOW-UP EM COUNTERPARTS OF GW TRIGGERS DETECTED BY ALIGO AND AVIRGO. TO IDENTIFY EM COUNTERPARTS SWIFT WILL PERFORM A LARGE SCALE SHALLOW TILING COVERING THE HIGHEST PROBABILITY REGIONS FROM WHICH THE GW TRIGGER IS LIKELY TO HAVE ORIGINATED. THESE ARE SELECTED BY CONVOLVING THE GW ERROR REGIONS WITH GALAXY CATALOGS. BASED ON LESSONS LEARNED DURING O2 INCLUDING THE DETECTION OF THE FIRST NS-NS MERGER EVENT WITH AN EM COUNTERPART GW 170817 AND THROUGH COLLABORATION WITH FERMI/GBM WE SEEK TO IMPROVE THIS FOLLOW-UP MAXIMIZING THE SCIENCE RETURN. IN ADDITION WE REQUEST DEEP FOLLOW-UP OBSERVATIONS AT HIGH PRIORITY IN ORDER TO DETECT AND CHARACTERIZE ANY EM COUNTERPART DETECTED EITHER BY SWIFT OR OTHER OBSERVATORIES IN X-RAY OR OPTICAL/UV.