Late Central Engine Activity in GRB 180205A

Becerra, R. L.; Watson, A. M.; Fraija, N.; Butler, N. R.; Lee, W. H.; Troja, E.; Román-Zúñiga, C. G.; Kutyrev, A. S.; Álvarez Nuñez, L. C.; Ángeles, F.; Chapa, O.; Cuevas, S.; Farah, A. S.; Fuentes-Fernández, J.; Figueroa, L.; Langarica, R.; Quirós, F.; Ruíz-Díaz-Soto, J.; Tinoco, C. G. Tejada S. J.
eprint arXiv:1901.06051


We present optical photometry of the afterglow of the long GRB 180205A with the COATLI telescope from 217 seconds to about 5 days after the {\itshape Swift}/BAT trigger. We analyse this photometry in the conjunction with the X-ray light curve from {\itshape Swift}/XRT. The late-time light curves and spectra are consistent with the standard forward-shock scenario. However, the early-time optical and X-ray light curves show non-typical behavior; the optical light curve exhibits a flat plateau while the X-ray light curve shows a flare. We explore several scenarios and conclude that the most likely explanation for the early behavior is late activity of the central engine.