[vsnet-alert 25437] Re: ZTF20acyxwzf = ASASSN-21au: rapid fading with superhump-like variations

[Graeme Coates]

 ASASSN-21au: Feb 22.857 - 22.967

( 350mm reflector + ST2000XM, Standlake, UK. )
Showed variation between ~15.9CV and 16.2CV, with humps supporting the
period of ~0.04d as per previous message by Kojiguchi-san. (Plot:
https://britastro.org/observations/observation.php?id=20210223_003812_658d84a1778cfe92).
Conditions deteriorated and prevented capture of further periods.

Data is uploaded to the BAAVSS and AAVSO databases for further analysis.

GC



On Mon, 22 Feb 2021 at 02:56, Kojiguchi Naoto <
kojiguchi at kusastro.kyoto-u.ac.jp> wrote:

> ZTF20acyxwzf = ASASSN-21au: rapid fading with superhump-like variations
>
>      Itoh-san, Kubotera-san, Tonny Vanmunster, Kyoto U. team,
> Tamas Tordai, Moriyama-san and Maehara-san have reported further
> observations.
> According to observations by Itoh-san, Kubotera-san and Kyoto U. team,
> this object shows rapid fading with superhump-like variations on Feb. 21.
> The superhump-like variations period is 0.0405 d. According to my O-C
> analysis, the superhump-like variations period seems almost constant, but
> the phase average profile seems to be changing.
>
> This object is showing very interesting behavior.
>
> Time-resolved photometry is encouraged.
> Even if this object is faint, nightly snapshots are important. Because
> this object is likely to cause rebrightenings.
>
>    20210218.058 13.710CV Van
>    20210218.475 13.575C Kub
>    20210218.477 13.646C Ioh
>    20210218.812 13.594CV Trt
>    20210219.071 13.788CV Van
>    20210219.422 13.755C Ioh
>    20210219.430 13.596C Kub
>    20210219.758 138C Myy
>    20210219.861 132 Mhh
>    20210220.424 13.712C Ioh
>    20210220.503 13.789C Kub
>    20210220.804 132 Mhh
>    20210221.417 14.001C Ioh
>    20210221.586 14.316C Kub
>
>