Affiliation
American Association of Variable Star Observers (AAVSO)
Mon, 06/15/2020 - 18:04
Hello All,
I took some high resolution spectra of Bet Lyr last night, and just tried to input them into the system here. The system took the first file, but then rejected the rest as duplicates. I have attached the log here from that experience. I would think that the system is looking to see something in the FITS header.... but what? The times and target will be the same... the only difference will be the wavelength range of the individual FITS files. I'd like to be able to upload all the areas of interest for such a star (the He and H emission regions in this case). Ideas?
Software used was Demetra from start to finish.
Thanks!
~john (bkl)
File Upload
Hello John,
Based on the fact that the time is the same I am assuming that you are talking about separate echelle orders that you are trying to upload. Oddly enough you are the second person to comment on this today and yet it hasn't come up a single other time before now. Unfortunately, we don't have a good way to handle echelle. You can submit a combined 1D spectrum, but it appears we can't deal with multiple orders, which I just found out myself today. From talking with the original developer this is largely because it is difficult to connect multiple files together and visualize all of them. You also can't submit them as separate files, because the parser only checks the date/object and not the wavelength range. This is a clear issue, that I will work on fixing. It should be a relatively quick fix to make the parser a little smarter so that you can at least submit the individual orders. In time, though, I intend to make it possible to submit batch files that match the BESS standard. Unfortunately, this is not a small issue and will likely take some time to address. Please bear with us on this and I will try to make this fix a priority moving forward.
Thanks,
Bert Pablo
Staff Astronomer, AAVSO
Thanks for your speedy reply, Bert. Yep - I hear you about echelle orders... that is precisely the issue. I can easily wait for fixes. :-) and thank you for that. You are also quite correct that the assembly of multiple orders of an echelle spectra set is very challenging, and not quite realistic. I have tried over the years. Let me know if you would like some sample spectra FITS files to work with. I've got plenty.
~john
Hi Bert,
If you are looking for workable solutions, it might be worth contacting the database manager at the BAA.
The BAA spectroscopy database handles uploading and downloading of multi order echelle spectra. https://britastro.org/specdb/spectra_upload.php
It also plots the multiple orders, though not smoothly merging them unless the observer has already done this.
Cheers
Robin
See the spectra there by J Guarro Flo for example
Dear John and all,
A quick warning: Demetra-eShel is still in beta version, and we're actively working to release it soon. Beware that we've a newer version than the one you used (5.1.5.1 if I'm right). We've made some changes on the FITS keywords recently - it may have an impact on the databases acceptance. Please contact me (francois.cochard@shelyak.com) if you want or need to upgrade.
Regards,
François COCHARD (Shelyak & Demetra manager)
Thank you, François. I will contact you via email.
Best,
~john