[vsnet-campaign-dn 8109] Re: NSV01436 bright outburst - time-series plot

[Michael Linnolt]

Thank you for the photometry Tom. FYI, Arne did NOFS BV photometry on the variable and the 2 faint companions about a decade ago. The mean values for those 2 stars are V=19.2 (+/-0.17) and V=16.98 (+/-0.03). He found the variable itself varies between V~16 and V~19 in "quiescence" (2000-2002). Now it has started to make short, frequent outbursts to V=12.4 (since 2010). His data shows its color varies between B-V~ +0.3 to -0.2 when it is faint. This is challenging target due to the close companions. It may be difficult to separate the variable from even the brighter neighbor with typical amateur equipment.
BTW, could you do BV instead of gr?
Thanks,
Mike

----- Original Message -----
From: Tom Krajci <tom_krajci at tularosa.net>
Date: Wednesday, October 12, 2011 3:59 am
Subject: NSV01436 bright outburst - time-series plot
To: Taichi Kato <tkato at kusastro.kyoto-u.ac.jp>
Cc: vsnet-alert at ooruri.kusastro.kyoto-u.ac.jp, vsnet-outburst at ooruri.kusastro.kyoto-u.ac.jp, vsnet-outburst at yahoogroups.com, baavss-alert at yahoogroups.com, variable_star_forum at yahoogroups.com, vsnet-campaign-ip at ooruri.kusastro.kyoto-u.ac.jp, Mike Simonsen <mikesimonsen at aavso.org>, vsnet-campaign-dn at ooruri.kusastro.kyoto-u.ac.jp, Eddy Muyllaert <eddy.muyllaert1 at telenet.be>, vsnet-alert at yahoogroups.com, chat CBA <cba-chat at cbastro.org>, Michael Linnolt <linnolt at hawaii.edu>

> Attached jpeg shows results of uncalibrated, untransformed 
> analysis of 
> last night's run using Sloan r' filter.
> 
> This object probably has faded too much for me to do any more 
> filtered 
> observations.
> 
> Is this object worthy of periodic coverage to determine outburst 
> frequency?
> -- 
> -------------------------------------------
> Tom Krajci
> Cloudcroft, New Mexico
> http://picasaweb.google.com/tom.krajci
> 
> Center for Backyard Astrophysics (CBA)
> http://cbastro.org/ CBA New Mexico
> 
> American Association of Variable Star
> Observers (AAVSO): KTC http://www.aavso.org/
> -------------------------------------------
> 
> 
> On 10/11/2011 11:54 PM, Tom Krajci wrote:
> > griz images from Astrokolkhoz tonight show that this object is 
> blue, 
> > and is currently at approx. r' mag. 14.5  (This includes 
> the light of 
> > the faint neighbor approx. 3.5 arcsec away)
> >
> > Time series is being run tonight for six hours.
> >
> >
> >
> > On 10/10/2011 6:41 PM, Taichi Kato wrote:
> >>     Fwd from aavso-discussion by Mike Linnolt.
> >>     The object is potentially an IP with 
> brief outbursts.
> >>
> >> ===
> >>
> >> Just observed it a few hours ago at v=12.4 this is the 
> brightest 
> >> outburst
> >> since its "reactivation" last year.
> >> A brief summary of the star:
> >> This is one of the old Ross variables which was discovered 
> early in 
> >> the 20th
> >> century and had only a few historically recorded outbursts. 
> It was 
> >> found to
> >> be around v=18 to 19 several times in the past decade. Last 
> year it 
> >> began
> >> frequent eruptions to v~13, and each eruption seems to be 
> getting 
> >> brighter
> >> at the peak, as today it is at its brightest in the last 50 
> years at 
> >> least!
> >> Could this be a UGZ which has been in a standstill around 
> V~16 the past
> >> decade or more, finally resuming its outbursting behavior? 
> Very unusual
> >> variable, indeed.
> >>
> >>
> >> Mike LMK
> >>
> >
>
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