A comprehensive study of stars in the Ultraviolet region

Supervisor: Dr. Ernst Paunzen

Contact information: ernst.paunzen@univie.ac.at 

Expected duration: 9 months

Project description & Goals:

The UV region (here defined as blueward of 3600A) is significant for all types of stars. It contains a similar rich line spectrum as the classical region but is most important to determine the astrophysical parameters (Teff, log, and [M/H]) and the reddening of stars. Most of the wavelength region is only accessible above the earth’s atmosphere. Several satellite experiments were designed to measure the flux of stars in the UV: GALEX, IUE, TD1, and the HST, to mention a few. All of these measurements are publicly available but were never compiled and analysed homogeneously. Another most important topic is the flux of stars in Johnson U and Stroemgren u from the ground. This first part of the thesis will be focused on the compilation of a catalogue of the already published magnitudes. The second part will include the analysis of intrinsic colours and reddening laws. Together with the forthcoming Gaia data releases, this compilation and its analysis will set a standard for numerous fields of astrophysics.

Working plan & Milestones (including final thesis):

1. Compilation of all available data in the ultraviolet region
2. Cross-match the data and calculate mean values
3. Compilation of the final catalogue
4. Get intrinsic colours and estimate the individual reddening values for each object

Requirements / special skills: NA

References:

Carnochan: https://ui.adsabs.harvard.edu/abs/1982MNRAS.201.1139C/abstract 

Gutierrez-Moreno:https://ui.adsabs.harvard.edu/abs/1975PASP...87..805G/abstract