With component masses of 116 times the mass of the Sun and 89 times the mass of the Sun, the 1 Myr old eclipsing binary A1 at the heart of the starburst cluster in the giant HII region NGC 3603 is among the most massive stars in the Galaxy. Using our high-angular resolution Lucky Imaging camera AstraLux Sur at the New Technology Telescope at the European Southern Observatory in La Silla, Chile, we have obtained high-quality photometric data of its primary and secondary eclipses.

The tasks for the diploma thesis are

1. to analyze the 140 data sets observed in March and April 2009 and in January and February 2010 in order to extract the photometric information
2. to phase the observations to obtain lightcurves in the SDSSi- and SDSSz-bands, and to improve the orbital period estimate by comparison with J-band lightcurves obtained ten years ago
3. to model the lightcurves in all three bands with the aim to derive fundamental astrophysical parameters like radii, effective temperatures, and luminosities of the binary components.

The ultimate goal is to firmly establish these parameters for stars located at the upper end of the mass function.

As part of the Diploma thesis, the student might also have the opportunity to participate in one of the upcoming observing runs with the Lucky Imaging camera AstraLux at the Calar Alto 2.2m telescope in Spain.

While a large part of the analysis can be carried out with existing data pipelines (written in IDL) and software packages (DAOPHOT or StarFinder for the photometry, Nightfall for the lightcurve analysis), some familiarity with a programming language would be advantageous.