TITLE: GCN CIRCULAR NUMBER: 30498 SUBJECT: GRB210724A: MeerLICHT upper limits DATE: 21/07/24 22:56:14 GMT FROM: Simon de Wet at University of Cape Town S. de Wet (UCT), P.J. Groot (Radboud/UCT/SAAO), A.J. Levan (Radboud), P.M. Vreeswijk (Radboud), report on behalf of the MeerLICHT consortium: Following the detection of GRB210724A by Swift and its X-ray counterpart (D'Avanzo et al., GCN30497), the 0.6m MeerLICHT telescope, located at Sutherland, South Africa obtained a repeating series of 60s images in the q,u,q,g,q,r,q,i,q,z bands. Observations began at 2021-07-24, 20:25:18.02 UT, 11 minutes after the Swift detection, and 2 minutes after the distribution of the BAT alert, and continued untill 21:27:36 UT. We detect no optical afterglow at the XRT position (D’Avanzo et al. GCN30497) in our first u,g,q,r,i,z exposures to 5-sigma limiting magnitudes of: u > 18.59 at 20:27:37 UT g > 19.40 at 20:31:01 UT q > 19.77 at 20:25:49 UT r > 19.38 at 20:34:31 UT i > 19.26 at 20:37:45 UT z > 18.14 at 20:59:12 UT Full moon conditions limited the depth of our exposures. We do note that an r=21.5 object is visible within the XRT localisation in PanSTARRS imaging of the field, and is a plausible host galaxy. MeerLICHT is built and run by a consortium consisting of Radboud University, University of Cape Town, the South African Astronomical Observatory, the University of Oxford, the University of Manchester and the University of Amsterdam. Disclaimer - University of Cape Town This email is subject to UCT policies and email disclaimer published on our website at http://www.uct.ac.za/main/email-disclaimer or obtainable from +27 21 650 9111. If this email is not related to the business of UCT, it is sent by the sender in an individual capacity. Please report security incidents or abuse via https://csirt.uct.ac.za/page/report-an-incident.php.