{
  "circularId": 33790,
  "body": "B. Schneider (MIT), C. Adami (LAM/Pytheas/AMU), J. T. Palmerio (GEPI, \nObs. de Paris), S. Basa (LAM), E. Le Floc'h, D. Götz (CEA Paris-Saclay), \nS. D. Vergani (GEPI, Obs. de Paris), C. Barthelemy, Q. Desvigne, \nJ. Latour (AMU), D. Turpin (CEA Paris-Saclay), report on behalf of a \nlarger collaboration:\n\nWe observed the field of GRB 230510A (Fermi GBM team, GCN 33751; Eyles-Ferris \net al., GCN 33752) using the T193cm and T120cm telescopes at Observatoire de \nHaute-Provence (France) respectively equipped with the MISTRAL spectro-imager\nand the T120 CCD camera. A total of 8 exposures were obtained in the imaging \nmode of MISTRAL in the r-band filter (6x600s + 2x300s) and 50 exposures \nwere obtained with the T120 CCD camera in the r-band filter (50x90s). \nObservations were made from 2023 11 May 01:24:26 UT to 2023 11 May 03:00:47 UT \n(mid time ~13.2h after trigger).\n\nIn the combined frames, we detect a faint source consistent with the \nX-ray afterglow position reported by Evans et al. (GCN 33756) and \nwith the optical afterglow position reported by Jiang et al. (GCN 33761). \nThe source is detected by both instruments at the same position.\n\nCombining the MISTRAL and T120 images, we measured a magnitude of \nr = 21.8 +/- 0.2, in agreement with the value determined individually for \neach instrument. The faintest PanStarr DR1 object detected at 3 sigma \nin the combined image is at r = 22. The photometric calibration was \nperformed using nearby stars from the PS1 catalog and the magnitude \nis not corrected for Galactic extinction.\n\nWe acknowledge the excellent support from Observatoire de Haute-Provence, \nin particular Jean Balcaen for the MISTRAL observations, Yoann Degot-Longhi, \nStephane Favard, Luc Favre, and Christelle Eyraud for the T120 observations.",
  "bibcode": "2023GCN.33790....1S",
  "createdOn": 1683967197140,
  "submitter": "Damien Turpin at CEA-Saclay <dturpin-astro@hotmail.com>",
  "eventId": "GRB 230510A",
  "subject": "GRB 230510A: OHP/T193 and OHP/T120 optical observations"
}