{
  "bibcode": "2023GCN.33539....1K",
  "body": "T. Komesh (NU), Zh. Maksut (NU), B. Grossan (UCB, NU), Zh. Abdullayev (NU), M. Krugov (FAI), report on behalf of the Energetic Cosmos Laboratory:\n\nThe Nazarbayev University Transient Telescope at Assy-Turgen Astrophysical Observatory (NUTTelA-TAO) pointed at GRB230328B on receipt of an automated GCN / BAT position alert, observing in Sloan g', r' and i' bands, with the Burst Simultaneous Three-Channel Imager (BSTI; Grossan, Kumar & Smoot 2019, JHEA, 32, 14).\n\nWe started observations at UT 2023-03-28 14:55:23, 41 s after the BAT trigger. Observations were made under clear conditions. A new and changing source consistent with the XRT position (Osborne 2023, GCN 33529) was detected. Note that these observations provide essentially full-time coverage, simultaneous in all three bands. We report the following photometric values for the OT:\n\n\ntc-t0(s)  g'(mag)   exposure_time (s)                               \n--------    -------    --------   \n 68       17.1     54\n 125     17.1     60       \n 185     17.5     60       \n 245     17.6     60       \n 305     18.0     60       \n 365     18.0     60       \n 440     18.6     90       \n 530     18.8     90       \n 620     19.1     90       \n 725     19.1     120       \n 845     19.8     120       \n 965     17.7     120       \n\n tc-t0(s)    r'(mag)    i'(mag)      exposure_time (s)\n------    --------     ------          -------\n45       16.5        16.1              7.5\n53       16.5        15.9              7.5\n60       16.4        16.0              7.5\n68       16.8        16.0              7.5\n75       16.4        15.9              7.5\n83       16.6        16.1              7.5\n90       16.5        15.9              7.5\n119      16.8        16.1               15\n134      16.7        16.2               15\n149      16.6        16.2               15\n164      17.0        16.3               15\n179      16.8        16.3               15\n194      17.0        16.3               15\n209      16.8        16.6               15\n224      17.0        16.8               15\n239      17.2        16.7               15\n254      17.2        16.8               15\n269      17.3        16.7               15\n284      17.2        16.8               15\n299      17.2        16.9               15\n314      17.2        17.1               15\n329      17.4        17.1               15\n344      17.5        16.9               15\n359      17.6        17.3               15\n374      17.4        16.9               15\n389      17.6        17.6               15\n404      17.8        17.1               15\n419      17.8        16.9               15\n434      17.5        17.1               15\n449      17.6        17.3               15\n464      17.8        17.4               15\n479      17.4        17.0               15\n494      18.1        17.1               15\n509      17.5        17.3               15\n524      17.7        17.1               15\n539      18.4        17.5               15\n554      17.6        17.2               15\n569      17.9        17.7               15\n584      18.0        17.2               15\n599      17.6        17.6               15\n614      17.7        17.4               15\n629      17.8        17.5               15\n644      17.6        17.2               15\n659      17.8        17.5               15\n674      17.6        17.6               15\n689      18.1        17.3               15\n704      18.0        17.5               15\n719      17.8        17.5               15\n734      17.9        17.5               15\n749      18.1        17.3               15\n764      18.1        17.3               15\n779      18.2        17.8               15\n794      18.0        17.6               15\n809      18.3        17.5               15\n824      18.5        17.5               15\n839      18.2        17.4               15\n854      18.1        17.4               15\n869      18.0        18.4               15\n884      17.8        17.8               15\n899      18.4        17.8               15\n914      18.4        17.1               15\n929      17.9        18.1               15\n944      17.8        17.3               15\n959      18.3        18.3               15\n974      18.1        17.1               15\n989      18.1        17.9               15\n1004     18.3        17.6               15\n\n\nUncertainties are estimated at ~ 0.1 mag for all three filters except the latest images of g��� with indications of errors ~ 0.15 mag. tc-t0 = trigger time minus image center time. Calibration was done with 3-4 bright Pan-STARRS catalog stars on our images, and no other analysis or corrections.\n\nWe caution the reader that these are preliminary results, without color or other corrections, and will likely change in small measure. Please also note that times are approximate.\n\n----------------------------------\nNU = Nazarbayev University, Nur-Sultan, Kazakhstan\nUCB = University of California, Berkeley, USA\nFAI = Fesenkov Astrophysical Institute, Kazakhstan\n\nThis research has been funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP14870504). The NUTTelA-TAO Team acknowledges the support of the staff of the Assy-Turgen Astrophysical Observatory, Almaty, Kazakhstan, and the Fesenkov Astrophysical Institute, Almaty, Kazkhstan.",
  "circularId": 33539,
  "createdOn": 1680112830000,
  "email": "toktarkhan.komesh@nu.edu.kz",
  "subject": "GRB 230328B NUTTelA-TAO / BSTI Early Measurements",
  "submitter": "Toktarkhan Komesh at Nazarbayev University  <toktarkhan.komesh@nu.edu.kz>",
  "eventId": "GRB 230328B"
}