TITLE:   GCN CIRCULAR
NUMBER:  37420
SUBJECT: GRB 240905E: Gaoyazi/GOT optical upper limits
DATE:    24/09/07 11:11:06 GMT
FROM:    Dong Xu at NAOC/CAS <dxu@nao.cas.cn>

S.Y. Fu, J. An, S.Q. Jiang, X. Liu, Z.P. Zhu, D. Xu (NAOC) report on behalf of a large collaboration:

We observed the field of GRB 240905E detected by Swift/BAT (Dichiara et al., GCN 37397), and SVOM/GRM (Zhang et al., GCN 37404), using the GOT-0.5m telescope located at Gaoyazi, Xinjiang, China. Observations started at 18:26:46 UT on 2024-09-05, i.e., 43 s after the Swift/BAT trigger, and a series of frames were obtained in the Sloan r- and z-filter.

No optical source is detected in our stacked image at the refined Swift/XRT position (Ferro et al., GCN 37406), down to the 5-sigma limiting magnitudes of r > 19.9 mag (AB) at 0.32 hr post-burst and z > 18.7 mag at 2.55 hr post-burst, calibrated with nearby PanSTARRS stars and not corrected for Galactic extinction.

We acknowledge the excellent support from L.F. Huo and M.M. Yang for enabling these observations.