Fig. 4: A comparison of the counterpart of GRB 230307A with AT2017gfo associated with GW170817.
From: Heavy-element production in a compact object merger observed by JWST
AT2017gfo has been scaled to the same distance as GRB 230307A. Beyond about 2 days, the kilonova dominates the counterpart. The decay rates in both the optical and infrared are very similar to those in AT2017gfo. These are too rapid for any plausible afterglow model. There is also good agreement in the late-time slope between the measurements made at 4.4 microns with the JWST and at 4.5 microns for AT2017gfo with Spitzer24. Error bars refer to the 1σ uncertainty.
