GRB 230510B: MAXI/GSC detection
Abstract
The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at 21:22:03 UT 10 May 2023. Assuming that the source flux was constant over the transit, we obtain the source position at (R.A., Dec) = (0.692 deg, 27.541 deg) = (00 02 46, +27 32 27) (J2000) with a statistical 90% C.L. elliptical error region with long and short radii of 0.15 deg and 0.14 deg, respectively. The roll angle of long axis from the north direction is 139.0 deg counterclockwise. Without assumptions on the source constancy, we obtain a rectangular error box for the transient source with the following corners: (R.A., Dec) = (0.127, 28.437) deg = (00 00 30, +28 26 13) (J2000) (R.A., Dec) = (359.878, 28.290) deg = (23 59 30, +28 17 23) (J2000) (R.A., Dec) = (0.966, 26.843) deg = (00 03 51, +26 50 34) (J2000) (R.A., Dec) = (1.213, 26.988) deg = (00 04 51, +26 59 16) (J2000) There is an additional systematic uncertainty of 0.1 deg (90% containment radius). The trigger time and position was consistent with that of GRB 230510B (Fermi GBM, GCN 33759) The X-ray flux averaged over the scan was 635 +- 75 mCrab (4.0-10.0keV, 1 sigma error). There was no significant excess flux in the previous transit at 19:49 UT and in the next transit at 22:54 UT with an upper limit of 20 mCrab for each.
- Publication:
-
GRB Coordinates Network
- Pub Date:
- May 2023
- Bibcode:
- 2023GCN.33760....1N