ASASSN-15qr possible superoutburst
Known SU UMa star.
YYYYMMDD(UT) mag observer
20210929.1733 15.932zr (Zwicky Transient Facility Lasair (Masci+ 2019))
Dear colleagues,
I have just finished analysing my time-series observations of ASASSN-21sb,
obtained on 2021, Sep 25/26 and Sep 26/27 at resp. CBA Extremadura
Observatory and CBA Belgium observatory, using 0.40-m telescopes with SX-46
CCD and QHY-268M CMOS camera's.
Regular superhumps with an amplitude of 0.32 mag are clearly visible in the
resulting light curve, establishing ASASSN-21sb as a new SU UMa-type dwarf
nova. A period analysis using the ANOVA, Lomb-Scargle,
Generalized-Lomb-Scargle and PDM methods (Peranso 3.0), yields a combined
superhump period of 0.0589 +/- 0.0003d. The object was at mag CV = 16.2 on
Sep 27th.
I will send my observations to AAVSO, CBA and VSNET for further analysis.
Best regards
Tonny
---
Tonny Vanmunster
CBA Belgium Observatory
CBA Extremadura Observatory
http://www.cbabelgium.com
PERANSO : The Light Curve and Period Analysis Software
http://www.peranso.com
IPHASJ190812.63+045728.1: eclipsing dwarf nova in the period gap
From ZTF data. Porb=0.1056882(3) d.
Eclipse epoch: BJD 2458662.020.
The behavior up to now suggests an SS Cyg star, but
a search for a superoutburst would be interesting.
LL And: stage A superhumps and mass ratio
Kyoto U. team, Crimean Astrophys. Obs. team,
Itoh-san, Alexandra Zubareva, Tonny Vanmunster,
Tamas Tordai, Filipp Romanov and Kiyota-san have
reported observations.
The object started to show well-detectable
superhumps since Sep. 20. The current period
(stage A) is 0.0579(1) d. This period corresponds to
q=0.143(5). This value is consistent with the result in
https://ui.adsabs.harvard.edu/abs/2004PASJ...56S.135K/abstract
This object is likely an SU UMa star (rather than
a WZ Sge star) as judged from the mass ratio
despite the very long supercycle.
The lack of strong early superhumps appears to be
consistent with this classification.