TITLE: GCN CIRCULAR NUMBER: 39384 SUBJECT: GRB 250219A: OHP/T193 optical upper limit DATE: 25/02/20 10:49:09 GMT FROM: Christophe Adami at LAM christophe.adami@lam.fr
C. Adami (LAM/Pytheas/AMU), B. Schneider (LAM), M. Dennefeld (IAP/CNRS/Sorbonne U.), J. P. Palmerio (CEA/Irfu), E. Le Floc'h (CEA/Irfu), D. Turpin (CEA/Irfu), S. Basa (UAR Pytheas) report on behalf of a larger collaboration:
We observed the field of the GRB 250219A (Daigne et al., GCN 39376) using the T193cm telescope at Observatoire de Haute-Provence (France) equipped with the MISTRAL spectro-imager. We obtained 7 exposures (1x360s, 1x720s and 5x600s) in the r-band starting at 01:11:32 UT on 2025-02-20 (9.3h after the trigger).
In the stacked image, we do not detect any new source at the XRT source #1 position (Evans et al., GCN 39377) down to the following 3-sigma limit:
r > 22.68 mag AB
This value is consistent with previously reported detections or upper limits on the optical afterglow (Xin et al., GCN 39380; Lagioia et al., GCN 39381; Magnani et al., GCN 39382; Fu et al., GCN 39383).
The photometric calibration was performed using nearby stars from the PanSTARRS catalog and the magnitude is not corrected for Galactic extinction.
We acknowledge the excellent support from Observatoire de Haute-Provence and in particular Stephane Favard, Yasmine Davis and Alix Freckelton for the MISTRAL observations. 
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