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I am trying to find radial velocity using FXCOR. I give it the target fits file and the template star fits file. I then use the command " :tempvel 34.7 " without the quotes to give fxcor the template star velocity. It simply does not take that but instead uses 0 Km/s as the velocity and computes the Vhelio. When i type "v" it gives me the error stating that it used 0 Km/s as the template star velocity. This is very frustrating. Please help!

I'll check on whether the :tempvel command is actually functional, but another way to set the template velocity is to put the value in the header as a VHELIO keyword. You might also check the 'v' output for additional errors such as missing keywords that might also prevent the correct calculation.-Mike

Thanks Mike as always for your quick response. I will check what you just asked me to. In the meantime I did the following:Once the "green window" or IRAFTERM window is open I typed the following commands: :unlearn
:tempvel 34.7In the xgterm I get "ERROR: Floating point invalid operation" and in the IRAFTERM I get "Cross-correlating lp624-54apr.fits[1] with vb10.fits[1]" Not sure what it means :tempvel has worked in the past. If you remember I had asked you few months ago about finding radial velocity using fxcor. We had 9 posts on that and I have followed as you suggested.

I just forgot. The tempvel command seems to work sometime, rarely though but intermittently. I start fxcor and quit and after several of this trials it works....but there is no assurance that it will work again. Do not know why this is so.

Sorry for all the posts. But adding VHELIO in the header works! I am really excited that it does because I have NOT even started working on the poster for the upcoming AAS meeting in AUSTIN.

I'll be in Austin next week as well, stop by the NOAO or NVO booth (or posters on Wed) and we can chat some more if you're still having problems.Cheers,
-Mike