[vsnet-outburst 25931] Re: MASTER OT J004527.52+503213.8 outburst

[Keisuke Isogai]

Dear all,

>   20201022.3253  21.1:g  ZTF  Last non-detection by ZTF
This value is taken from "difference magnitude" in the ZTF Lasair,
but we should use "apparent magnitude" at least for ordinary dwarf
novae having a visible counterpart. Actually, the counterpart in PS1
is g=18.9, is brighter than the above value. The difference magnitude
would be used for supernovae placed on the host galaxy.

Best regards,
Keisuke Isogai

On 2020/10/25 3:20, Denis Denisenko d.v.denisenko at gmail.com via vsnet-alert wrote:
> The brightest dwarf nova discovered by MASTER (12.5m unfiltered on
> 2013 Sep. 17.668 UT, ATel #5399) is in bright outburst on ZTF and
> ASAS-SN images.
>
> MASTER OT J004527.52+503213.8
>    20201021.2778  <172g   ASAS-SN
>    20201022.3253  21.1:g  ZTF  Last non-detection by ZTF
>    20201022.8889  <14.3V  Eddy Muyllaert (via AAVSO)
>    20201024.3066  13.26r  ZTF  Outburst!
>    20201024.3417  13.04g  ZTF  Outburst!
>    20201024.4326  13.00g  ASAS-SN
>    20201024.4338  12.99g  ASAS-SN
>    20201024.4351  13.00g  ASAS-SN
>
> ZTF light curve (Masci et al., 2019):
> https://lasair.roe.ac.uk/object/ZTF18abtyikp/
> ASAS-SN light curve and data for last 20 days (Shappee et al.,
> Kochanek et al.):
> https://asas-sn.osu.edu/light_curves/59408ebf-2932-44c0-8164-f76430e53173
>
> The discovery outburst in September-October 2013 was followed by the
> rebrightening to 15m six days after fading to 18m. The superoutburst
> itself lasted at least 12 days (2013 Sep. 17-29). The superhump period
> was measured as 0.08115 d [vsnet-alert 16425], 0.080464 d [vsnet-alert
> 16433] and 0.07999 d [vsnet-alert 16463].
>
> Time-resolved photometry is encouraged.
>
> Discovery ATel with the links to DSS finder chart and images:
> http://www.astronomerstelegram.org/?read=5399
>
> Denis Denisenko