EP-WXT Pathfinder LEIA discovered an X-ray transient LXT 221107A


EP-WXT Pathfinder LEIA (Lobster Eye Imager for Astronomy) detected a new X-ray transient on November 07, 2022. The source position is R.A. = 91.02 deg, DEC = 12.76 deg (J2000) with an uncertainty of 3 arcmin (radius, 90% C.L. statistical and systematic). The source has been detected in 9 observations of LEIA from 2022/11/07T06:26:36 to 2022/11/08T12:25:24, with a flux gradually rising from 7.7 x 10-11 erg cm-2 s-1 to 3.6 x 10-10 erg cm-2 s-1 in 0.5 - 4.0 keV. Its spectrum can be well fitted by a power-law with a photon index of ~1.2. 

There is a ROSAT source (2RXS J060415.1+124554/HD 251108) within the error circle with a flux of 8.246 x 10-12 erg cm-2 s-1 at a separation of 2.5 arcmin, which is fainter than the source detected by LEIA at least by a factor of 10. 

Due to the unknown nature of this source, we tentatively identify this source as a new X-ray transient and name it as LXT 221107A. 

Follow-up observations are encouraged to identify this new transient.

The preliminary image of LXT 221107A detected by EP-WXT Pathfinder LEIA from one observation.

The preliminary results have been posted at Astronomer's Telegram as ATel 15748. Click here for more EP/LEIA Astronomer's Telegrams.