GRB 190701A: MAXI/GSC detection

The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient source at 09:46:42 UT on July 1, 2019. Assuming that the source flux was constant over the transit, we obtain the source position at (R.A., Dec) = (27.548 deg, 58.852 deg) = (01 50 11, +58 51 06) (J2000) with a 90% C.L. statistical error of 0.16 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: (25.762, 59.105) deg = (01 43 02, +59 06 17) (J2000) (25.721, 58.781) deg = (01 42 53, +58 46 51) (J2000) (29.166, 58.620) deg = (01 56 39, +58 37 11) (J2000) (29.239, 58.942) deg = (01 56 57, +58 56 31) (J2000). This position is consistent with that of GRB 190701A detected by Swift (Ukwatta et al., GCN 24934, Evans et al., GCN 24935). The X-ray flux averaged over the scan was 416 +- 39 mCrab (4.0-10.0keV, 1 sigma error). There was no significant excess flux in the previous transit at UT 08:14 and in the next transit at 11:19 UT with an upper limit of 20 mCrab for each.