GOALS AND OBJECTIVESMASS LOSS IN EVOLVED MASSIVE STARS IS ONE OF THE LEAST UNDERSTOOD YET FUNDAMENTAL ASPECTS OF STELLAR EVOLUTION. HOW AND WHEN DO MASSIVE STARS LOSE THEIR H-ENVELOPES? THIS CENTRAL QUESTION MOTIVATES THIS PROPOSAL. WE REQUEST NUSTAR OBSERVATIONS TO MAP THE UNIQUE SITUATION OF THE INTERACTION OF AN H-STRIPPED SN2014C WITH AN H-RICH SHELL EJECTED BY ITS PROGENITOR STAR AS PART OF OUR RADIO-TOGAMMA-RAY FOLLOW-UP. OUR GOAL IS TO CONSTRAIN THE DENSITY AND PROXIMITY OF THE EJECTED MATERIAL AND HENCE THE MASS-LOSS HISTORY OF THE PROGENITOR STAR. UNLIKE ALL THE OTHER H-STRIPPED SNE THE RADIO AND X-RAY EMISSION OF SN14C IS STILL INCREASING AT T GREATER THAN 300 DAYS GIVING US THE UNPRECEDENTED OPPORTUNITY TO MAP THE DENSITY PROFILE OF THE EJECTED MATERIAL AND CONSTRAIN THE EPOCH OF ITS EJECTION IN FINE DETAIL.

Northwestern University, Evanston IL

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