TCP J15244460-6059200 (N) (submitted to VSX)
RA 15h24m47.62s DE -60°59'47.3" (Gaia DR3, equinox and epoch J2000.0) Discoverer: Andrew Pearce (Nedlands, Western Australia) http://www.cbat.eps.harvard.edu/unconf/followups/J15244460-6059200.html
Elias Aydi et al.: "SOAR spectroscopic follow-up of the Galactic optical transient TCP J15244460-6059200" (ATel #15473): https://www.astronomerstelegram.org/?read=15473
Quote: "The spectrum resembles that of a very fast classical nova after optical peak. The low amplitude of the transient raises questions about its nature and the possible progenitor match. TCP J15244460-6059200 could be an unusually low-amplitude, ultra-fast nova or a more exotic phenomenon. There is a slight chance that the actual progenitor system is much fainter and coincides with the bright (~14 mag) match, which would explain the unusually low- amplitude of the transient."
The likely progenitor is the Gaia DR3 source 5875610751015084544 (Gmag. 13.75, BP-RP= 0.73, Teff ~22500 K, parallax 0.11 ± 0.02 mas, distance 6.5 ± 0.8 kpc). SMSS data: gPSF= 13.98, rPSF= 13.70, iPSF= 13.74 APASS data: V= 13.88, B= 14.35, g'= 14.08, r'= 13.70, i'= 13.65
So the eruption amplitude seems to be only 3 magnitudes! And the likely progenitor does not look like a typical CV in quiescence.
ASAS-SN Sky Patrol (Shappee et al. 2014ApJ...788...48S and Kochanek et al. 2017PASP..129j4502K) light curves and data: https://asas-sn.osu.edu/sky-patrol/coordinate/63cd3b67-9d82-41da-869e-4d1222... https://asas-sn.osu.edu/sky-patrol/coordinate/a61c2edb-9cab-4d5c-b9cf-f886b5... TCPJ15244460-6059200 20220619.1200 14.00g ASN TCPJ15244460-6059200 20220625.2002 10.91g ASN TCPJ15244460-6059200 20220625.2015 10.92g ASN TCPJ15244460-6059200 20220625.2027 10.97g ASN TCPJ15244460-6059200 20220625.9486 12.00g ASN TCPJ15244460-6059200 20220625.9498 11.96g ASN TCPJ15244460-6059200 20220625.9510 12.00g ASN TCPJ15244460-6059200 20220626.2656 12.28g ASN TCPJ15244460-6059200 20220626.2668 12.27g ASN TCPJ15244460-6059200 20220626.2682 12.28g ASN TCPJ15244460-6059200 20220626.9602 12.71g ASN TCPJ15244460-6059200 20220626.9615 12.65g ASN TCPJ15244460-6059200 20220626.9628 12.81g ASN
Could the apparent fading trend in ASAS-3 data be real? http://www.astrouw.edu.pl/cgi-asas/asas_variable/152448-6059.8,asas3,0,9755....
Further spectroscopy and multiband photometry are required.
Clear skies, Patrick
vsnet-alert@ooruri.kusastro.kyoto-u.ac.jp