[vsnet-alert 11210] Re: re NSV 18024 and ASAS J150946-2147.7 and V1129Cen

[eruptors at Safe-mail.net]

Aha, thanks for the update.  I thought I remembered something about that case but found nothing on a literature search and obviously didn't think to do a maillist search.

So just the new Libra object and V1129 Cen then, both including the variable HeII emission.

The dated quoted measures in the Washington Double Star Catalog are a bit ambiguous re physical binarity of HD 74771 = JSP 298, they suggest optical at worst but are only sixteen years and 0.7 arcsecs different which could equally amount to no relative motion within errors so "unable to say" at best.  Proper motion of the primary, from Hipparcos data, is pretty negligible and likely to be unmeasurabe for B even given archival plates.  The current WDS Notes (sourced via vizier here) note that B is a cataclysmic variable and probably optical likely based on that astrometric information.  I've no idea if any radial velocity data exists.

USNO urls have all moved around a bit but I'll try and find the one where the full WDS measures are 'orderable' and request them.  I've a bit of deja vu on that, so I may well have done that afore around the time of your original email.  As WDS notes a measure from 1929 as the first on record and one from 1945 as the last on record, there won't be much.  Doesn't look like Jessup's original measure will be readily provenanced given the reference dates for his papers included in the WDS references.  Ah, the number of observations logged in the WDS is _2_, so in fact that'll mean the 1929 and 1945 measures will be all there are.

Cheers again for the update

John

-------- Original Message --------
From: "Howard E. Bond" <bond at stsci.edu>
To: eruptors at Safe-mail.net
Cc: vsnet-alert at ooruri.kusastro.kyoto-u.ac.jp
Subject: Re: [vsnet-alert 11209] re NSV 18024 and ASAS J150946-2147.7 and V1129Cen
Date: Sat, 25 Apr 2009 17:00:12 -0400

> eruptors at Safe-mail.net wrote:
> > 
> > In case peeps are missing this similarity :-
> > 
> > NSV 18024
> > 
> > <http://www.astrouw.edu.pl/cgi-asas/asas_variable/084434-3757.9,asas3,0,0,1000,0>
> > 
> 
> In regard to NSV 18024 = HD 74771, I point out that observations made during an
> outburst in 2008 April were described by me in [vsnet-alert 10110], which I can
> summarize by saying that the system is a visual binary composed of the more or
> less normal HD star (spectral type G8 IV/V according to N. Houk) and a variable
> companion 6".8 away. 
> 
> Spectra obtained during the 2008 April outburst confirmed strong, broad emission
> lines in the blue companion, which is normally at about 15th magnitude.  The
> system is probably a physical pair, with HD 74771B being the cataclysmic
> variable. It thus differs from ASAS J150946-2147.7 and V1129 Cen = HD 109962, in
> both of which the bright star IS an interacting component.
> 
> Howard E. Bond
> Space Telescope Science Institute