Forum der Vereinigung der Sternfreunde

I am looking at measuring equivalent widths and have looked at IRAF, ISIS and Vspec.

However, I also came across ARES http://www.astro.up.pt/~sousasag/ares/ which automates the process.

Has anyone any experience of installing or using ARES if so I would like to have your comments.

Thanks Andrew

Hi Andrew, ARES seems to be a well designed tool. One should keep in mind, though, that it uses Gaussian line fits for the EW measurements and for the respective error estimations. I hence presume that it is only useful for absorption lines (at least I do not read something else). It is thus probably not applicable for emission line stars as Be and especially WR stars or Novae (mostly observed by amateurs) with their broad lines dominated by their winds.
Cheers, Thomas

Thanks Thomas, I am mainly interested in absorption lines at the moment. I attach a first attempt using SPLOT on some data from Rho Cas on 3 FeI lines . SPLOT though manual seems to be quite robust to small changes in the continuum estimate and my results seem to be in the right area looking at data from A Lobel et. al.

I would like to get advice on best practice in the area of Equivalent Width measurement.

I have found a paper by P B Stenson and E Pancino on DAOSPEC ( another automatic program) that has a good discussion on the issues involved in the measurement.

Regards Andrew