(Proposal ID) S13B-078

(PI) Maeda, Keiichi

(Proposal Title)
Searching for A Light Echo from SN Ia 2011fe

(Abstract)
We propose very late-time (~ 850 days after the explosion) spectroscopic and 
photometric observations of SN Ia 2011fe in M101. Its proximity provides a 
unique, once in a generation, opportunity to follow up the evolution until 
very late. Our main aim is to search for a light echo due to scattered light 
at its surroundings, which links the SN properties and environment. If 
detected, it is the first example of an echo from a normal SN Ia showing 
little extinction. Even if not detected, the proposed observation will place a 
strong limit on the nature of environment around SN 2011fe within a sub-parsec 
scale (~ 0.3 - 0.7pc) fully complementary to that probed by other methods 
(< 0.01pc). As such, this will provide an important insight on origin(s) of a 
light echo from SNe Ia, and a relation between the nature of SNe Ia and the 
CSM/ISM environment. Also, the intrinsic SN component will contain valuable 
information to study the progenitor and explosion of SNe Ia, so far 
unavailable for any SNe Ia in such a late phase.