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,  P.D. Dr. Roberto P. Saglia, P.D. Dr. Ariel G. Sánchez, and Dr. Jens Thomas.

The research of the group focuses on dark energy and dark matter in the Universe, and on the properties of local and distant galaxies. 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 and with dynamical models.
• 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 of local and distant galaxies, their stellar populations, their formation and evolution
• to study supermassive black holes and how they influence the central regions of galaxies

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 the Euclid Space Mission, ESO VLT 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 (HST). We have guaranteed access to ESO telescopes for providing instruments (e.g., soon MICADO).

Developing and applying highly advanced orbit-based dynamical models we seach for supermassive black holes, reconstruct the stellar orbital distributions and formation histories of galaxies and measure precise dark matter halo profiles to constrin the nature of datk matter.

Our group participates with  a significant role in large international surveys. Examples are the completed Baryon Oscillation Spectroscopic Survey (BOSS), the on-going extended BOSS (eBOSS), the Dark Energy Survey (DES), the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX), the Prime Focus Spectrograph

( PSF), the Dark Energy Spectroscopic Instrument ( DESI). 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. A recent examples is Schwarzschild's orbit superposition method used in our search for the most massive black holes in the local universe..

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, and Göttingen). We are currently in the building phase of MICADO, an infrared imager and spectrograph that will serve as the first light instrument for the E-ELT. 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 1 (PhD or Master Project in the OPINAS Group): "Dynamical modeling of multiple stellar populations" Dynamical modeling of stellar motions has played a crucial role in revealing that the outer regions of galaxies are dominated by dark matter. In addition, sophisticated orbit-based Schwarzschild models have shown that nearly every galaxy harbors a supermassive black hole at its center. Surprisingly, recent advances in dynamical modeling have uncovered a possible third source of unseen mass: the central regions of galaxies appear to contain more mass than expected if the stellar initial mass function (IMF) resembles that of the Milky Way. This excess mass may be the signature of extreme IMFs, potentially shaped by the intense conditions under which the first stars formed at high redshift. To investigate this possibility, we have developed powerful dynamical orbit -modeling tools capable of simultaneously analyzing multiple stellar populations. This project will apply these models to rich datasets from previous surveys - primarily focused on early-type galaxies - to test whether IMF variations can account for the excess central mass, or if the findings hint at new aspects of dark matter.  We have also recently extended the Schwarzschild method to model disk galaxies with bars. Depending on the student's interests, the project could involve adapting our multi-population modeling framework - originally developed for early-type galaxies - to study disk galaxies. In comparison to early types, our knowledge of the IMF, dark matter distribution, and central black holes in disk galaxies is still quite limited.   Project 2 (PhD or Master Project in the OPINAS Group): "Constraining the Dark Energy equation of state studying the Large Scale Structure of the Universe" A new generation of large-volume galaxy surveys, such as DESI and Euclid, are mapping the Universe's large-scale structure (LSS) with unprecedented detail, presenting us with a unique opportunity for precision cosmology. However, the accuracy of these data sets demands an urgent revision of traditional analysis methods, which are not fit for purpose. The existing methodologies for LSS studies discard significant portions of the available data to mitigate modelling uncertainties in the non-linear regime and are therefore inadequate for the analysis of the new datasets. This project aims to develop new, accurate tools based on a combination of numerical simulations and perturbation theory predictions to extract the maximum amount of information from the new surveys. The application of these tools to DESI and Euclid data will allow us to put the standard ΛCDM model to its most stringent test yet.		Jens Thomas jthomas@mpe.mpg.de Roberto Saglia saglia@mpe.mpg.de                   Ariel Sanchez arielsan@mpe.mpg.de