A search for optical transients associated with fast radio burst 150418†‡

Abstract

We have searched for optical variability in the host galaxy of the radio variable source possibly associated with fast radio burst (FRB) 150418. We compare images of the galaxy taken 1 day after the burst using Subaru/Suprime-Cam with images taken ∼1 yr after the burst using Gemini-South/GMOS. No optical variability is found between the two epochs with a limiting absolute magnitude ≳ -19 (AB). This limit applies to the optical variability of the putative active galactic nucleus in the galaxy on a timescale of ∼1 yr, and also to the luminosity of an optical counterpart of FRB 150418 one day after the burst should it have occurred in this galaxy.