TITLE: GCN CIRCULAR NUMBER: 33336 SUBJECT: GRB 230216A: Swift-BAT refined analysis DATE: 23/02/17 19:01:37 GMT FROM: Hans Krimm at NSF/NASA-GSFC M. Stamatikos (OSU), S. D. Barthelmy (GSFC), N. J. Klingler (GSFC/UMBC/CRESSTII) H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU), (i.e. the Swift-BAT team): Using the data set from T-240 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 230216A (trigger #1154815) (Klingler, et al., GCN Circ. 33328). The BAT ground-calculated position is RA, Dec = 113.966, -7.993 deg which is RA(J2000) = 07h 35m 51.9s Dec(J2000) = -07d 59' 36.2" with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment). The partial coding was 85%. The mask-weighted light curve shows a trio of peaks at approximately T-80 sec, T-20 sec and T+0 sec, with some possible substructure and other, smaller peaks. T90 (15-350 keV) is 91.20 +- 7.31 sec (estimated error including systematics). The time-averaged spectrum from T-81.07 to T+16.40 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.90 +- 0.23. The fluence in the 15-150 keV band is 1.3 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T-0.13 sec in the 15-150 keV band is 1.2 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/1154815/BA/ Dr. Hans A. Krimm, Program Officer Divisional of Astronomical Sciences National Science Foundation 2415 Eisenhower Avenue, Room W9158 Alexandria, VA 22314 Tel: 703-292-2761