(Proposal ID) S17B-010

(PI) Totani, Tomonori

(Proposal Title)
Subaru Follow-up of Fast Radio Bursts

(Abstract)
Fast Radio Bursts (FRBs) are a mysterious transient phenomenon whose duration 
is only a few msec. Their distances are estimated to be cosmological 
(z ~ 0.5-1) from the large dispersion measures, implying exciting possibilities
of using them as a new cosmological probe. Here we propose to continue Subaru 
follow-up for FRBs to detect the first optical variable counterpart and reveal 
the progenitors. The unique wide-field imaging capability of Subaru to cover 
the entire FRB error regions (~14 arcmin diameter FWHM) with 8m-class 
sensitivity is especially powerful. This has indeed been proven by our Subaru 
follow-up observations for FRB 150418. We continue the collaboration with the 
FRB search team using the Parkes radio observatory, and expect a few FRB 
events in the S17B semester. Some proposed FRB scenarios predict detectable 
optical counterparts on time scales from days to months, and we will search 
optical transients on various time scales depending on the telescope schedule 
at the time of a FRB alert.  We also request to use any of optical/NIR 
spectroscopic/imaging instruments of Subaru for follow-up of particularly 
interesting objects found by other observatories or our own HSC observations.