Central Bureau for Astronomical Telegrams

CBAT "Transient Object Followup Reports"

TCP J18490521-1902054

TCP J18490521-1902054   2021 03 25.7609*  18 49 05.21 -19 02 05.4  10.8 U             Sgr       9 0

2021 03 25.761

Discovered by Hideo Nishimura, Kakegawa, Shizuoka-ken, Japan, who found this star on six frames (limit mag.= 15) taken with Canon EOS 6D digital camera + 200-mm f/3.2 lens, who writes nothing is visible at the discovery position on three frames taken on 2021 Mar. 23.778 UT with same instrument.

2021 03 25.8034

Mag.=11.2, position end figures 05.2s, 06", independent discovery of this TCP by Yuji Nakamura, Kameyama, Mie, Japan, on two frames (15-s exp. limiting mag 12.0) taken by 135mm F4.0 lens + CCD.

2021 03 26.1875

mag 11.3U; R.A. = 18h49m05s.06, Decl. = -19 02 04.0 TEL 0.4-m f/2.8 reflector + CCD Atik460ex. Exp = 3x5s. Observer F. Kugel, Banon 04, France.

2021 03 25.2927

This transient had already been reported by the All-Sky Automated Survey for Supernovae (ASAS-SN) as ASASSN-21eh ("bright CV candidate, matches to PS1 g=20.0, g>18.1 on 2021-03-23.31, g=11.9 on 2021-03-25.29"): http://www.astronomy.ohio-state.edu/~assassin/transients.html —— PSO J184905.064-190204.346 (gmag. 19.98, rmag. 19.53, imag. 19.36) = Gaia EDR3 4086385340323308544 = VHS J184905.06-190204.3 is indeed the likely progenitor, as it is very close to the position measured by François Kugel. Patrick Schmeer (Saarbrücken-Bischmisheim, Germany)

2021 03 25.2927

No previous brightenings were recorded the ASAS-SN Sky Patrol (Shappee et al. 2014ApJ...788...48S and Kochanek et al. 2017PASP..129j4502K) since 2015 March 21; complete light curve and data at https://asas-sn.osu.edu/sky-patrol/coordinate/2bc7259b-d5f1-4c9c-bff3-4b7e63c54571 —— Patrick Schmeer (Saarbrücken-Bischmisheim, Germany)

2021 03 26.740

Mag.= 11.0, position end figures 05s.06, 03".9 observed by T. Noguchi, Katori, Japan, using 0.23-m f/10 Schmidt Cassegrain + unfiltered CCD (KAF-0261E), An image at http://park8.wakwak.com/~ngc/images/TCPinSgr_20210326.jpg.

2021 03 26.5038

Mag. 10.869(V) and 11.177 (B) in 2x20s and 2x30 exposures taken with the 0.43-m reflector + CCD at iTelescope.NET, Mayhill, New Mexico, US. Position end figures 05.07s and 04.4". Observer Robert Fidrich, Budapest, Hungary. Image URL: https://tinyurl.com/2hvzk8ja