[vsnet-alert 10799] Re: re ST CHA in outburst?

[Boris.Gaensicke at warwick.ac.uk]

Hi John, 

> (I don't want to hear that it's visual data, folk'd be amazed what info 
> quality visual data can carry if they just look)...

some variations in the mass transfer rate will occur on time scales of 
days, which will prevent an orbital period measurement from a set of 
perfectly fine one-point-per-day monitoring data *but* frequent 
one-point-per-day monitoring will eventually tell provide a clue on the 
nature as UGZ or NL. That's where a good long uninterrupted time series 
run might help.

There are a number of similar (CV) beasts out there - shallow broad 
absorption lines, a hint of Halpha emission, low-amplitude erratic 
variability on longer time scales, but dead flat over a few hours, e.g. 
the NL HS0139+0559, http://uk.arxiv.org/abs/astro-ph/0507342, Fig. 2 and 
Fig. 6. [great quality photometry from the late Bob Fried] However, 
spectroscopy does reveal a 4h period... a textbook example of a CV with an 
optically thick accretion disc, but it has been a hard nut to crack.

> Incidentally, anyone know why the United Kingdom built the Liverpool 
> Telescope or whatever it's called, and/or what it's used for?  

http://telescope.livjm.ac.uk/Pubs/

not good for long time series, I'm afraid...

over and out on this topic, before I get banned as spammer as well! 

Cheers, 

Boris