Re: New Cepheid?

[Doug Welch <welch@physics.mcmaster.ca>]

Mike,

As someone who knows a few things about Cepheids, I would say that
this one is an excellent candidate. Congrats! The reddening along
the northern Milky Way can be quite high in places, so I don't think
the color is really a problem. (Check its position in a J-H,H-K diagram
if you want to be more sure of its spectral type.) Said differently,
the Cepheids in catalogues tend to be the ones with the lowest
reddenings!

Once the NSVS site gets back online, it should be possible to
improve the period somewhat. (I suspect that their OID's wrapped in
their Postgresql database - they have 3.3Gobservations and a 32-bit
limit on OID's - not too much breathing space!)

Cheers,
Doug
 
On Sun, 2004-03-21 at 10:33, Michael Sallman wrote:
> Yeah, I thought that might wake you guys up. :-)
> 
> I have been working on the database in preparation for this years data. 
> As I was working on cleaning up the W-S stats, I ran across this star:
> http://sallman.tass-survey.org/servlet/markiv/template/TassPlot.vm?object_id=6349369
> (Plot)
> http://sallman.tass-survey.org/servlet/markiv/action/DataDownload?position=57.1069+59.4424
> (Data)
> The star is GSC 3729-1127. 2MASS J-K is .895.
> 
> Using both Patrick's PDM program and Period98, I get a period of approx. 
> 5 days. (there are a few slightly more significant frequencies, but they 
> are all greater than the Nyquist freq.)
> Could this be a Cepheid? The star is quite a bit redder than any of the 
> other Cepheids in the area.
> 
> +---------+---------+---------+-------------+------------------+
> | id      | ra      | decl    | v_avg-i_avg | comments         |
> +---------+---------+---------+-------------+------------------+
> | 6318548 | 50.9481 | 59.3552 |       1.675 | AC Cam -- DCEP   |
> | 6318874 | 52.3567 | 60.4458 |       1.609 | AD Cam * -- DCEP |
> | 6369151 | 54.0833 | 62.2882 |       1.466 | AM Cam -- CEP    |
> | 6368297 | 56.5340 | 58.7840 |       1.291 | AB Cam * -- DCEP |
> | 6349369 | 57.1069 | 59.4424 |       1.928 | NULL             |
> | 6368677 | 58.5905 | 58.6535 |       1.459 | RW Cam * -- DCEP |
> +---------+---------+---------+-------------+------------------+
> 
> Any thoughts?
> 
> Mike
> 
> P.S. I seem to recall a website that had plots of the Fourier 
> coefficients for different variables (Cepheid, RR Lyr, Delta Sct, etc.), 
> but I can't seem to find it again. Anyone know of such a site?
> 
>