TITLE:   GCN CIRCULAR
NUMBER:  38499
SUBJECT: GRB 241209B: BOOTES-5 optical upper limit
DATE:    24/12/09 21:04:22 GMT
FROM:    ipg@iaa.es

I. Perez-Garcia,  E. J. Fernandez-Garcia, G. Garcia-Segura, M. D. Caballero-Garcia, S.-Y. Wu, R. Sanchez-Ramirez, S. Guziy and A. J. Castro-Tirado (IAA-CSIC, Granada), C. Perez del Pulgar, A. Castellon (Univ. de Malaga), Y.-D. Hu (INAF-OAB, Brera), S. Jeong (ADD, Daejeon) and D. Hiriart and W. H. Lee (UNAM), on behalf of a larger collaboration, report:

Following the detection of GRB 241209B by SVOM/ECLAIRs (Xie et al. GCNC [38478](https://gcn.nasa.gov/circulars/38478)), the 0.6m BOOTES-5/JG robotic telescope at Observatorio Astronomico Nacional in San Pedro Martir (Mexico) observed the GRB location starting on Dec 09, 07:01 UT (3.1 hours after trigger and 30 minutes after notification) in different optical bands. No new optical source is detected on the co-added images (15x60s, clear-filter) within the SVOM/ECLAIRs error box down to 20.3 mag.

We thank the staff at Observatorio Astronomico Nacional in San Pedro Martir for their excellent support.