WE PROPOSE DEEP LATE-TIME OBSERVATIONS WITH XMM-NEWTON OF TWO OF THE NEAREST KNOWN SUPERLUMINOUS SUPERNOVAE (SLSNE) 2017EGM AND 2016EAY TO PERFORM A FOCUSED TEST OF THE POPULAR MODEL FOR THE POWER SOURCE OF HYDROGEN-POOR SLSNE THAT RELIES ON THE SPINDOWN ENERGY OF RAPIDLY ROTATING NEWLY BORN MAGNETARS. OUR PREVIOUS LATE-TIME OBSERVATION OF THE SLSN 2015BN WITH XMMNEWTON RESULTED IN A NON-DETECTION INDICATING THAT LESS THAN 2% OF THE INFERRED SPINDOWN ENERGY OF THE MAGNETAR WAS BEING EMITTED AT UVOIR OR X-RAY WAVELENGTHS AT LATE TIMES IDENTIFYING A MISSING ENERGY PROBLEM. WE SEEK TO TEST WHETHER THIS IS A GENERIC PROBLEM BY PERFORMING LATE-TIME XMM-NEWTON OBSERVATIONS OF THESE TWO OBJECTS BY MEASURING THE LUMINOSITY OF X-RAYS ESCAPING THE EJECTA AT AGES OF 2-3 YEARS.

Ohio University, Athens OH

Investigators