This could be interesting: vsnet-alert 27948
Swift J1727.8-1613: black-hole binary and V404 Cyg-like object ?
Swift and MAXI detected an outburst in Swift J1727.8-1613.
This is a candidate for a black-hole binary and possibly similar to
V404 Cyg, a unique object known as a source of rapid variability.
A few seconds variability was already found in X-rays.
The most violent variability would be ~2 mag in several tens of min.
This is very bright. Currently, ~13 mag.
The position is (RA)17:27:46 (DEC)-16:12:53 reported by Swift.
Follow-up observations are strongly encouraged.
- Mariko Kimura at Kanazawa Univ. in Japan