GRB 190823A: MAXI/GSC detection
Abstract
The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at 13:30:22 UT on 2019 August 23. Assuming that the source flux was constant over the transit, we obtain the source position at (R.A., Dec) = (279.278 deg, -43.439 deg) = (18 37 06, -43 26 19) (J2000) with a 90% C.L. statistical error of 0.17 deg and an additional systematic uncertainty of 0.1 deg (90% containment radius). Without assumptions on the source constancy, we obtain a rectangular error box for the transient source with the following corners: (R.A., Dec) = (280.193, -43.737) deg = (18 40 46, -43 44 13) (J2000) (R.A., Dec) = (280.285, -43.434) deg = (18 41 08, -43 26 02) (J2000) (R.A., Dec) = (278.903, -43.205) deg = (18 35 36, -43 12 17) (J2000) (R.A., Dec) = (278.804, -43.508) deg = (18 35 12, -43 30 28) (J2000) The X-ray flux averaged over the scan was 322 +- 29 mCrab (4.0-10.0keV, 1 sigma error). There was no significant excess flux in the previous transit at UT 11:57 with an upper limit of 20 mCrab.
- Publication:
-
GRB Coordinates Network
- Pub Date:
- August 2019
- Bibcode:
- 2019GCN.25456....1I