TITLE: GCN CIRCULAR NUMBER: 25651 SUBJECT: GRB190829A: GROND detection of the accompanying SN DATE: 19/09/04 10:14:13 GMT FROM: Jan Bolmer at MPE/Garching J. Bolmer, J. Greiner, and T.-W. Chen (all MPE) report We have been using GROND (Greiner et al. 2008, PASP 120, 405) to follow up the afterglow of GRB 190829A (Dichiara et al., GCN 25552) at z=0.08 (Valeev et al., GCN 25565). The light of the optical transient has been fading in all GROND bands during the first days, was then flattening and is now finally showing a relativley sharp rise in all seven GROND bands (e.g. about 0.5 mag in z' to 19.55 +/- 0.03 mag_AB; 330s integration time) between 4.5 and 5.5 days after the BAT trigger. This behavior can be interpreted as the upcoming supernova component. Further spectroscopic follow up is encouraged.