NY Serpentis: SU UMa-type dwarf nova at standstill?

Affiliation
Association Francaise des Observateurs d'Etoiles Variables (AFOEV)
Thu, 03/15/2018 - 08:18

NY Serpentis (UGSU+UGZ:)
https://www.aavso.org/vsx/index.php?view=detail.top&oid=34891

The SU UMa-type [sic!] dwarf nova NY Serpentis apparently entered an Z Cam-like standstill phase around 20 January 2018. Spectroscopy is recommended.

Taichi Kato writes (vsnet-alert 21972):
"NY Ser: likely standstill
Crimean Astrophys. Obs. team (+ Kazan' team) and Kyoto U. team have reported observations.
There has been no apparent signal of superhumps. The current state appears to be a 'pure' standstill, rather than a permanent superhumping state.
This object probably became the first clear example of a (pure, without superhumps) standstill in an SU UMa-type dwarf nova. The type then would be UGSU+UGZ. There was no indication of a long standstill in the ASAS-SN light curve in the past four years."

Affiliation
Association Francaise des Observateurs d'Etoiles Variables (AFOEV)
Now a second standstill!

After the previous (first ever recorded) standstill of this SU UMa-type dwarf nova had ended on 17 March 2018, another standstill was reported by the Crimean Astrophysical Observatory (CrAO) team on 29 May (vsnet-alert 22195 and 22199).

*** Spectroscopy is urgently required! ***

Clear skies,
Patrick