Master- and PhD-Theses

The USM-MPE extragalactic research group is a joint effort of the University Observatory of Munich (USM) and the Max-Planck Institute for Extraterrestrial Physics. The group is located both at the USM (see `Extragalactic Astronomy') and at MPE. Senior group members are Prof. Ralf Bender, Dr. Maximilian Fabricius, Prof. Ortwin Gerhard, Dr. Ulrich Hopp, P.D. Dr. Roberto P. Saglia, P.D. Dr. Ariel G. Sánchez, Dr. Stella Seitz and Dr. Jens Thomas.

The research of the group focuses on dark energy and dark matter in the Universe, on the properties of local and distant galaxies, and on extrasolar planets. The aims of our current science projects are:

to constrain the nature of dark matter by analysing cluster and galaxy dark matter halo profiles with strong and weak lensing in combination with dynamical and photometric information for nearby galaxies
to derive constraints on the nature of dark energy, by studying the large-scale structure of the Universe by means of weak lensing and clustering measurements
to understand the structure and dynamics of local and distant galaxies, their stellar populations, their formation and evolution
to reconstruct the dark matter mass distribution and chemodynamical history of the Milky Way from the current revolutionary survey data, giving us a template for galaxy formation
to quantify the role of black holes and dark matter in galaxies
to search for extrasolar planets and understand their properties (mass, density, atmosphere).

We pursue these science questions with a combination of optical and near-infrared observations, theory, numerical modelling, and data interpretation.

The observational data necessary for our scientific programs come from a large variety of telescopes, primarily ESO telescopes, the Hobby-Eberly Telescope (HET), the 2.7m telescope of the McDonald observatory, the USM 2m Fraunhofer telescope at the Wendelstein observatory in the Bavarian Alps and also space (HST) and survey (e.g. SDSS) telescopes. We also have guaranteed access to ESO telescopes for providing instruments (e.g. OmegaCAM, KMOS, MICADO).

We carry out studies of black holes in local galaxies without active galactic nuclei, measuring their masses through stellar dynamics. Using similar techniques we reconstruct the stellar orbital distributions and dark matter halos of dwarf and giant early-type galaxies or globular clusters. Exploiting the multiplexing capabilities of our KMOS spectrograph, we study galaxy evolution up to redshift 2.5 by observing large samples of star forming and passive galaxies.

Our group also has a significant role in large international surveys. Examples are the completed Baryon Oscillation Spectroscopic Survey (BOSS), the on-going extended BOSS (eBOSS) and Dark Energy Survey (DES), and future surveys such as the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) and the ESA space mission Euclid. Galaxy clustering and gravitational lensing measurements based on these data sets probe the large-scale structure of the universe with unprecedented precision, providing invaluable information on the nature of dark matter and dark energy, the growth of structure, neutrino masses and inflationary physics. The design, construction, analysis, modelling and interpretation of these data sets are some of the main activities of our group.

The numerical modelling required for our projects is based on state-of-the-art algorithms run on supercomputers. Some of these methods are developed or implemented within our group. Recent examples are Schwarzschild's orbit superposition method used for measuring black hole masses, and the NMAGIC adaptive N-body code for modelling galaxy dynamics.

In addition, the USM-MPE extragalactic research group is designing and building imaging and spectroscopy instruments for 1-10m class telescopes, together with national and international partners. We built, e.g., the FORS1-2 and KMOS instruments for the VLT, the OmegaCAM 1-square-degree imager for VST, all the instruments for the Wendelstein telescopes (WWFI, 3kk, FOCES and VIRUS-W, currently at McDonald Observatory), and the Low Resolution Spectrograph 2 (LRS2) for the 10m HET in Texas (which we share with the Universities of Texas, Penn State University, Standford and Göttingen). We are currently in the design phase of MICADO, a multi-IFU infrared spectrograph that will serve as the first light instrument for the E-ELT, and the near-infrared optical system for the ESA space mission Euclid, planned to be launched in 2020. We also provide software for the giant optical IFU spectrograph VIRUS for HET.

MASTER- AND PHD-THESIS PROJECTS :

Please use our webpages for further information about the research activities of the extragalactic research group at USM and the optical & interpretative astronomy group at MPE. We continuously offer Master projects (please contact us also by email and ask for further projects).

Master and/or PHD THESIS PROJECTS		SUPERVISOR/CONTACT



Project 4 (Master Project in the OPINAS Group): "The internal kinematics of globular clusters" Even though they are some of the best studied objects in our nearby universe, many questions around the formation mechanisms of globular clusters remain unanswered. We are performing a systematic 2-dimensional kinematic mapping of the northern largest Milky Way globular clusters with our VIRUS-W instrument at the 2.7m McDonald telescope. Our goal is to constrain the internal kinematics of these objects, quantify the amount of global stellar rotation and possibly set constraints on their dark matter content. Moreover, we will investigate the stellar populations by mapping the strength of various absorption line indices: this will allow us to explore the possible gradients in age and metallicity within the globular clusters. The PhD project will involve observation trips at McDonald Observatory, data reduction and analysis and dynamical modeling.		Ralf Bender bender@mpe.mpg.de Roberto Saglia saglia@mpe.mpg.de
Project 5 (Master Project in the OPINAS Group): "The formation and orbital structure of disks, classical bulges, pseudo bulges and bars" The Schwarzschild algorithm solves the collisionless Boltzman equation by superposition of orbits, which represent the space of integrals of motion. By solving for the approriate orbital weights, the method allows to determine the masses of the stars, dark matter halos and central black holes together with the distribution of stellar orbits from observed surface brightness profiles and stellar kinematical maps. Schwarzschild models have been calibrated and work well for elliptical galaxies. Disk galaxies have not been studied in detail yet. Their analysis requires extensions to the currently used implementations of Schwarzschild's method: (1) accurate solutions of the Poisson equation for very flattened disks and for bars are needed; (2) an orbit sampling scheme needs to be developed that ensures inclusion of the many more families of orbits supported by these potentials. The project is aimed to expand the existing Schwarzschild code. In a second step, the student can analyse existing observational data for disk galaxies. The main questions are (1) whether the Mbh-sigma scaling relation is different for disk galaxies with pseudo bulges and with classical bulges and (2) what the orbital structure in disk galaxies tells us about the formation history of their various components.		Jens Thomas jthomas@mpe.mpg.de Roberto Saglia saglia@mpe.mpg.de









Project 14 (Master Project in the OPINAS Group in collaboration with ESO): "Rotating open clusters" In a recent work Leao et al. have shown that the Hyades cluster rotates with a velocity of about 20 m/sec/Pc. This is the first study demonstrating that open clusters rotate, using both astrometric and spectroscopic radial velocities of Hyades stars. Cluster rotation is possibly a signature of the hierarchical merging formation for open clusters. After becoming familiar with the theory and relevant literature, the master thesis will forllow two phases. During the first one, an available Phython code to compute astrometric radial velocities, clusters' parallaxes and velocity space will be improved to include cluster rotation. In a second phase the GAIA DR2 data of the Hyades will be used together with HARPS radial velocities to recompute the Hyades space motion including rotation and assess the cluster rotation to a much higher degree of confidence.		Roberto Saglia (saglia@mpe.mpg.de), Luca Pasquini (lpasquin@eso.org)