[vsnet-outburst 25501] Re: ASASSN-20jl update

[Tonny Vanmunster tonny.vanmunster@gmail.com via vsnet-outburst]

Dear Taichi,

 

I have been doing nightly snapshot photometry in B, V, R, I since July 31st,
2020. You can find my observations in the AAVSO database, and a screenshot
below. They show a steady decline in brightness, which is most pronounced in
B (0.125 mag/d), less in V (0.085 mag/d) and least in I (0.059 mag/d). Last
night (Aug 12, 2020) the object was at mag V = 14.17.

 

I will start an unfiltered time-series session of this target later tonight,
for about 3 hours.

 

Best regards
Tonny

 

--

Tonny Vanmunster

CBA Belgium Observatory

CBA Extremadura Observatory

www.cbabelgium.com

www.peranso.com

 



 

-----Original Message-----
From: vsnet-outburst
[mailto:vsnet-outburst-bounces at ooruri.kusastro.kyoto-u.ac.jp] On Behalf Of
Taichi Kato
Sent: donderdag 13 augustus 2020 8:14
To: variable_star_forum at yahoogroups.com;
vsnet-alert at ooruri.kusastro.kyoto-u.ac.jp; vsnet-alert at yahoogroups.com;
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vsnet-outburst at ooruri.kusastro.kyoto-u.ac.jp; vsnet-outburst at yahoogroups.com
Subject: [vsnet-outburst 25498] ASASSN-20jl update

 

ASASSN-20jl update

 

   Is there anyone following this target?

 

ASAS-SN data:

 <https://asas-sn.osu.edu/light_curves/063bb5c4-6298-4640-85b4-03635ad12aab>
https://asas-sn.osu.edu/light_curves/063bb5c4-6298-4640-85b4-03635ad12aab

 

   The light curve looks like to me a WZ Sge star (or less likely, a
background nova).  I suspect that the CV is a fainter (possibly unresolved)
companion of the V=14.7 mag star.  NUV=20.8 would be fine for a faint dwarf
nova in quiescence.  If this is indeed a WZ Sge star, the age may be
inconsistent with a G-type star (assuming that they are physically
associated).

 

   As judged from the light curve, it may be already superhumping if it is a
dwarf nova.  Spectroscopy is also desired (it was a pity that long rainy
season in Japan prevented observation).

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