[vsnet-chat 7815] Re: probably mis-classified UG stars

[Sebastián Otero]

Dear Seiichi,

> While monitoring the outburst of UG-type stars, I found there are some
> probably mis-classified stars.
>
> They are classified into UG-type in the GCVS. But some of them can be
> Mira type, or some of them seems almost constant at bright state.
>
> * V1050 Aql : R.A. 19h51m43s.4, Decl. +10o51'15", 14.5-17.5 mag(p)
>
>    It is bright and red in the USNO-A2.0, 14.6 mag(R) and 17.5
>    mag(B).
>
>    It is also recorded in the infrared catalog as IRAS 19493+1043.
>
>    It is also recorded as a long periodic variable NSVS
>    1951432+105114, with a period of 270 days.


VSX has the right type since 2009:
http://www.aavso.org/vsx/index.php?view=detail.top&oid=2189

It has been known as a mira since 1984:
http://adsabs.harvard.edu/abs/1984IBVS.2577....1G



> * HN Cyg : R.A. 19h33m39s.9, Decl. +28o56'14", 13.3-16.0 mag(p)
>
>    It is bright and red in the USNO-A2.0, 12.5 mag(R) and 15.9
>    mag(B).
>
>    It is also recorded in the infrared catalogs as IRAS 19316+2849
>    and MSX5C G063.2797+04.4706.


This one was known to be a red star since 1992:
http://adsabs.harvard.edu/abs/1992A&AS...93..419B

I have updated it in VSX since it was in VSX as a possible mira but it is a 
semiregular.
http://www.aavso.org/vsx/index.php?view=detail.top&oid=11134


> * V1285 Cyg : R.A. 19h44m49s.5, Decl. +35o59'35", 13.1-14.8 mag(p)
>
>    It is bright and red in the USNO-A2.0, 12.3 mag(R) and 14.2
>    mag(B).
>
>    It is also recorded in the infrared catalog as IRAS 19429+3552.
>    It looks bright in the 2MASS infrared images.

Also a SRB in VSX:
http://www.aavso.org/vsx/index.php?view=detail.top&oid=12205

Known since 1987:
http://adsabs.harvard.edu/abs/1987A&A...185..203B


> * UY Vul : R.A. 20h55m52s.8, Decl. +26o40'52", 13.0-<16 mag(p)
>
>    It is bright and red in the USNO-A2.0, 12.8 mag(R) and 16.6
>    mag(B).
>
>    It is also recorded in the infrared catalog as IRAS 20537+2629.
>
>    It is also recorded as a long periodic variable NSVS
>    2055525+264049, with a period of 626 days.

The same as HN Cyg, it was found to be a red star in 1992:
http://adsabs.harvard.edu/abs/1992A&AS...93..419B

It is in fact a mira with a period of 409 d:
http://www.aavso.org/vsx/index.php?view=detail.top&oid=38213


> * UZ Vul : R.A. 20h56m46s.0, Decl. +23o34'36", 14-<16 mag(p)
>
>    It is bright and red in the USNO-A2.0, 15.7 mag(R) and 18.3
>    mag(B).
>
>    It looks bright in the 2MASS infrared images.

Also in
http://adsabs.harvard.edu/abs/1992A&AS...93..419B
A 248 d. mira:
http://www.aavso.org/vsx/index.php?view=detail.top&oid=38214


> * KM Lac : R.A. 22h13m49s.4, Decl. +55o28'26", 14.8-<17.4 mag(p)
>
>    It is bright in the USNO-A2.0, 14.4 mag(R) and 15.1 mag(B).
>
>    It keeps almost constant around 14.5-15 mag from 2007 to 2012 in
>    the course of the MISAO Project survey.


The problem with this one is that it is in a close pair. The 14.5 V-mag. 
star is not the variable but the brighter companion 5" away. It is only in 
2MASS and NOMAD, not in USNO, GSC or UCAC.
This one was classified as UGSS in VSX.
Check out VSX for the right identification:
http://www.aavso.org/vsx/index.php?view=detail.top&oid=16835


> * LM Cas : R.A. 23h12m59s.9, Decl. +56o51'21", 15.8-<19 mag(p)
>
>    It is bright in the USNO-A2.0, 15.3 mag(R) and 16.0 mag(B).
>
>    It keeps almost constant around 16 mag from 2007 to 2012 in
>    the course of the MISAO Project survey.


The same situation, a brighter companion (V= 15.6) to the SW influencing the 
photometry.
The star is in GSC2.3 and SDSS.
VSX info:
http://www.aavso.org/vsx/index.php?view=detail.top&oid=6592


> * V381 Lac : R.A. 22h15m58s.9, Decl. +42o22'47", 12.5-<16.2 mag(V)
>  (Note that it is classified as NL, not UG, in the GCVS)
>
>    It is bright and red in the USNO-A2.0, 13.9 mag(R) and 17.1
>    mag(B).
>
>    It is also recorded in the infrared catalog as IRAS 22138+4207.
>
>    I found the following paper on this star, which suggests it is a
>    Mira variable.
>
> FBS 2213+421: A dust-enshrouded long-period AGB Mira variable?
> K. S. Gigoyan and D. Russeil
> Astrofizika, Vol. 49, No. 1, pp. 91--96 (February 2006).
> www.springerlink.com/index/d3144m831h713w40.pdf


That paper was also in VSX and type was M:.
However, NSVS data suggests it is a semiregular star with a main period of 
170 d. J-K is 5.4, extremely red(dened).
http://www.aavso.org/vsx/index.php?view=detail.top&oid=16970

So, search VSX when you have some doubt on classification, it is usually up 
to date and if it is not, then you can revise the record with the data you 
have found in the literature.

Cheers,
Sebastian

-------------------------
Sebastian Otero
VSX Team
American Association of Variable Star Observers