{
  "bibcode": "2022GCN.32253....1M",
  "body": "D. B. Malesani (Radboud Univ. and DAWN/NBI), L. Izzo (DARK/NBI), J. S. \nThomsen (NOT), R. Clavero (IAC) report on behalf of a larger collaboration:\n\nWe observed the field of GRB 220623A (Sbarufatti et al., GCN 32243) \nusing the Nordic Optical Telescope (NOT) equipped with the ALFOSC \nimager. Two sets of observations were acquired in the r and z filters, \nwith mid times 2022 Jun 23.890 and 23.903 UT (14.3 and 14.6 hr after the \ntrigger, respectively). The exposure times were 3x300 and 5x200 s in r \nand z, respectively.\n\nNo source is detected in our images within or close to the GRB XRT \nposition (Evans et al., GCN 32248), down to the following 3-sigma limits:\n\nr > 23.4 (AB);\nz > 22.5 (AB).\n\nFlux calibration was carried out against nearby stars from the \nPan-STARRS catalog.",
  "circularId": 32253,
  "createdOn": 1656027810000,
  "email": "d.malesani@astro.ru.nl",
  "subject": "GRB 220623A: NOT optical observations",
  "submitter": "Daniele B Malesani at Radboud U  <d.malesani@astro.ru.nl>",
  "eventId": "GRB 220623A"
}