{
  "bibcode": "2023GCN.33449....1I",
  "body": "Myungshin Im, Gregory S.-H. Paek, Mankeun Jeong, Seo-Won Chang, Hyeonho\nChoi (SNU), and Chung-Uk Lee (KASI)\n\nWe covered the localization areas of GRB 230307A (GBM team GCN 33405, Xiong\net al. GCN 33406) with the RASA36 telescope at the El Sauce observatory in\nChile, and the KMTNet telescopes in SSO, Australia, and SAAO, South Africa.\nThe RASA36 observation started at 2023-03-08-00:52 (UT) or about 9.11 hrs\nafter the burst alert, taking a series of r-band images for about 20 min.\nThe starting times of the KMTNet SSO and SAAO stations are 2023-03-08-09:39\n(UT) and 2023-03-08-18:30 (UT) or 17.89 hrs and 26.74 hrs respectively,\ntaking a series of R- and I-band images for about 1 hr at each location.\n\nWe clearly identify the afterglow (Levan et al. GCN 33439, Lipunov et al.\nGCN 33441, O'Conner et al. 33447) and confirm its fading nature in all of\nthe time-series KMTNet images, with the photometry roughly consistent with\nthat of the Levan et al. (GCN 33439) report. A weak signal is found in the\nRASA36 image.\nFurther observations and analysis are being carried out.\n\nWe thank the KMTNet operators for their support for the KMTNet observations.",
  "circularId": 33449,
  "createdOn": 1678434167000,
  "email": "mim@astro.snu.ac.kr",
  "subject": "GRB 230307A: GECKO optical observations and detections of the afterglow",
  "submitter": "Myungshin Im at Seoul Nat U  <mim@astro.snu.ac.kr>",
  "eventId": "GRB 230307A"
}