{
  "bibcode": "2019GCN.23786....1N",
  "body": "M. Nakamura, T. Sakamoto (AGU)\n\nWe observed the field of GRB 190123A detected by Swift\n(D'Ai et al., GCN Circ. 23769) with the 14-inch AGU Robotic\nOptical Monitor for Astrophysical object - Narrow (AROMA-N)\nlocated at the Sagamihara campus of Aoyama Gakuin University.\n\n30 images of 60 sec exposures were taken in the R filter\nstarting from January 23 12:21:49 (UT) about 156 seconds\nafter the trigger and stopped on January 23 12:58:25 (UT).\nWe do not detect the optical afterglow both in the individual\nimages and the stacked image.  The estimated five sigma\nupper limit of the combined image (total exposure of 1800 sec)\nis ~17.7 mag using the USNO-B1 catalog.",
  "circularId": 23786,
  "createdOn": 1548341971000,
  "email": "tsakamoto@phys.aoyama.ac.jp",
  "subject": "GRB 190123A: AROMA-N Optical Observation",
  "submitter": "Takanori Sakamoto at AGU  <tsakamoto@phys.aoyama.ac.jp>",
  "eventId": "GRB 190123A"
}