Fields of research for PhD projects
Extragalactic Astronomy and Cosmology
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
Senior group members are
Prof. Ralf Bender,
Dr. Maximilian Fabricius,
Prof. Ortwin Gerhard,
Dr. Ulrich Hopp,
Dr. Arno Riffeser,
P.D. Dr. Roberto P. Saglia,
Dr. Ariel G. Sanchez,
Dr. Stella Seitz,
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
- to search for extrasolar planets using the transit method in
wide field surveys 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
The observational data necessary for our scientific programs
come from a large variety of telescopes, primarily
the Hobby-Eberly Telescope
the 2.7-m telescope of the McDonald observatory,
the USM 2-m Fraunhofer telescope at the
observatory in the Bavarian Alps and also space
We also have guaranteed access to telescopes for providing instruments
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 participates with a significant role in
large international surveys.
Examples are the completed Baryon Oscillation Spectroscopic Survey
the on-going extended BOSS
and Dark Energy Survey (DES),
and future surveys such as the Hobby-Eberly Telescope Dark Energy Experiment
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.
This year we offer PhD projects within our group in the following
- Gravitational lensing
- Dynamical modelling galaxies
- Stellar content and structure of the Milky Way
- Cosmological analysis of galaxy clustering measurements
- Instrument development
For more details visit our homepages
Structure Formation and Cosmology
The research group on Cosmology and Structure Formation is pursuing
studies in cosmology and the formation and evolution of large scale
structures in the universe.
Our work is at the interface of observation and theory, where we
seek to bring together new observational constraints with state of
the art hydrodynamical simulations of structure formation.
We are pursuing cosmological topics such as the nature of the
cosmic acceleration and the characteristics of the initial density
Our ongoing structure formation studies focus on the properties and
evolution of the large scale structure, including clusters of galaxies,
the most massive collapsed structures in the universe.
Senior group members are
Prof. J. Mohr,
Dr. G. Bazin.
Opportunities exist for those who might be interested in the
South Pole Telescope Sunyaev-Zel’dovich Effect survey for
Here in Munich we are centrally involved in the optical and X-ray
followup of these systems, which are very cleanly selected, high mass
systems extending to redshifts z > 1.
These are truly unique and rare systems and are therefore well suited
for cosmology if we can successfully characterize their masses using
weak lensing, velocity dispersions and X-ray observations.
The SPT sample contains about 280 systems presently and will end
with approximately 500 massive clusters with accurate individual
cluster mass estimates, providing an unparalleled sample for studies
of cosmology, non-Gaussianity and the evolution of large scale
There are also opportunities to become involved in the
Dark Energy Survey,
which is a 5000 deg2, deep multiband optical survey
of the southern sky that will begin in Fall 2011.
Our group is focused on cluster science, large scale structure and
weak lensing studies.
In addition, we are involved in the development of the data management
system for processing, calibrating and archiving these data.
This familiarity with the data gives members of our group advantages
in pursuing any analyses that push the data to their limits.
We are working to develop the science case and novel analysis
techniques for the
all sky X-ray survey (PI Dr. Peter Predehl, MPE).
This survey will begin in 2013 and will deliver a sample of
105 galaxy clusters and 106 AGN that, in combination with
the multi-wavelength optical surveys like the Dark Energy Survey and
Pan-STARRS1, should provide the ideal sample for cosmological studies
using galaxy clusters and for structure formation and evolution
studies using both clusters and AGN.
Finally, there are opportunities to get involved with hydrodynamical
simulations of large scale structure.
Our group, in collaboration with Dr. Klaus Dolag at USM, is also
focused on delivering a next generation hydrodynamical simulation
that will reach a volume of 1 cubic gigaparsec with sufficient
resolution to follow the formation and evolution of galaxies.
These simulations will be central to a wide range of forefront studies,
and we expect to pursue some of these studies in combination with
data from SPT, DES and eROSITA.
We offer PhD projects within our group in any of the above science
Some examples of PhD projects:
- The evolution and nature of density fluctuations out to redshifts
beyond z = 1 using the SPT cluster sample.
- Clustering and evolution of galaxies using large photometric
redshift samples from the DES and spectroscopic extensions of these
surveys that will deliver large samples of spec-z’s.
- Evolution of the galaxy population and the intracluster medium
within massive clusters from the time of the formation of the first
such systems to the present.
- The underlying causes of the cosmic acceleration using techniques
that include the evolution of galaxy cluster populations and the
clustering of both galaxy clusters and galaxies.
- Development of novel algorithms for the improved processing and
calibration of photometric and spectroscopic optical data.
Galaxy clusters contain dark matter and baryons in the form of stars,
galaxies and a diffuse high temperature X-ray emitting plasma.
Galaxy clusters are the most massive collapsed structures in the
universe, and when they form all material in their vicinity is
The mix of baryonic and dark matter in clusters reflects the mix
in the Universe as a whole, allowing us to measure the dark matter
density of the Universe.
Computational and Theoretical Astrophysics
Research in the Computational Astrophysics Group (CAST) ranges from
the theoretical investigation of star and planet formation to studies
of processes on cosmological scales.
A variety of different, well-known numerical codes (such as Ramses,
Gadget, Sauron, Gandalf, Mocassin, and others) are used.
Primary investigations regard the formation, the structure, and
the evolution of protoplanetary discs, the formation of planetary
building blocks and planets, the relation between turbulence and phase
transitions in the multiphase interstellar medium (ISM), energetic
feedback processes, molecular cloud and star formation in galaxies as
well as cosmological structure and galaxy formation and the interplay
between feedback processes, AGN and galaxy evolution and their imprint
on the intergalactic medium (IGM) or the intercluster medium (ICM).
Thus, our group studies astrophysical processes on length scales
covering more than 14 orders of magnitude, from gigaparsec scales
of cosmological structures all the way down to sub-AU scales of dust
grains within protoplanetary discs.
It is now clear that small-scale processes like the condensation
of molecular clouds into stars, magnetic fields and the details of
heat transport as well as large-scale processes like gas infall from
the cosmic web into galaxies and environment are intimately coupled
and have to be investigated in a concerted effort.
The various past and ongoing PhD projects within the CAST group cover
a link between the various scales and contribute to our understanding
of crucial aspects of the formation and evolution of stars and
protoplanetary discs, central black holes and AGNs, star-forming
regions and the ISM, galaxies and their IGM, galaxy clusters and the
ICM as well the large-scale structures in the universe.
They also also drive the continuous effort to develop and to apply
new numerical methods and the next generation of multi-scale codes
within the framework of numerical astrophysics and allow students to
interact actively with master and bachelor students.
Past and ongoing PhD projects were always offered with respect
to the individual strengths and interests of the students and
cover various areas in the field of computational and theoretical
- Formation of large-scale cosmological structures (dark-matter
halos, galaxies, clusters of galaxies, role of black holes, magnetic
fields and non-thermal particles)
- Evolution and structure of the turbulent interstellar medium
(ISM physics, self-regulating star formation, formation of molecular
clouds, magnetic fields)
- Physics of galactic centres (active galactic nuclei, origin and
nature of the gas cloud G2 near the Galactic centre)
- Formation of planets, stars, and stellar clusters (stars and
their influence on the surrounding protoplanetary disc, interstellar
matter, radiative transfer, dynamics of particles and planets in
- Application and development of numerical tools on parallel CPUs
and GPUs and visualization (particle-based SPH/N-body, grid-based,
moving-mesh or meshless methods)
More detailed information on
ongoing and finished PhD projects
as well as more detailed information on ongoing research can be
found on the web pages of the computational astrophysics group members:
contact: A. Burkert and K. Dolag;
contact: B. Ercolano and T. Birnstiel;
Empirical Galaxy Formation Models,
contact: B. Moster.
Expanding Atmospheres of Hot Stars, Gaseous Nebulae, and Planetary Atmospheres
Hot Stars cover sub-groups of objects in different parts of the
HR diagram and at different evolutionary stages.
The most important sub-groups are massive O/B Stars,
Central Stars of Planetary Nebulae, and Supernovae.
All these objects have in common that they are characterized by high
radiation energy densities and expanding atmospheres.
Due to these properties, the state of the outermost parts of these
objects is characterized by non-equilibrium thermodynamics and
The USM Hot Star group is experienced in the corresponding
theory, especially of radiative transfer (1d and 3d) and of stellar
atmospheres, and accordingly in model simulations and the computation
of realistic synthetic spectra for these astrophysically important
Senior group members are
Prof. A. W. A. Pauldrach,
P.D. J. Puls,
P.D. K. Butler,
Dr. A. Kutepov.
Specific topics address the
relevance of Hot Stars for current astronomical research:
- The present cosmological question of the reionization of the
universe requires quantitative predictions about the influence of
very massive, extremely metal-poor Population III stars
on their galactic and intergalactic environment.
The objective is to deduce the ionization efficiency of a Top-heavy
IMF via realistic spectral energy distributions of these very massive
- Due to the impact of massive stars on their environment the
underlying physics for the spectral appearance of starburst
galaxies are rooted in the atmospheric expansion of massive
O stars which dominate the UV wavelength range in star-forming
Therefore, the UV-spectral features of massive O stars can be
used as tracers of age and chemical composition of starburst galaxies
even at high redshift.
- Distant SNe Ia appear fainter than standard candles in an
empty Friedmann model of the universe.
This surprising result requires investigating the role of Supernovae
of Type Ia as distance indicators with respect to diagnostic
issues of their spectra.
PhD Projects in this group available on:
- Diagnostics of UV and optical spectra of O-type stars
- Synthetic spectra of the X-ray range of O-type stars
- Synthetic spectra for SN Ia at late phases
- IR-spectroscopy of massive stars
- Clumping in hot star winds – constraints from a multi-wavelength analysis
The main focus of the working group thus is to develop diagnostic
techniques in order to extract the complete physical stellar
information from the spectra at all wavelength ranges.
More details about the USM Hot Star group
and further information on the projects can be found
Calculated and observed UV spectrum for ζ Puppis.
The observed spectrum shows the Copernicus and IUE high-resolution
observations, and the calculated spectrum represents a state-of-the-art
The Plasma-Physics group at the USM is involved in the
research of the macroscopic dynamics of astrophysical plasmas.
Senior group member is
Prof. H. Lesch.
99% of the visible Universe is
in the plasma state. Thus, the understanding of the dynamics
of cosmic multi-particle systems under the influence of
electromagnetic forces, is of outstanding importance.
Phenomena of special interest to our group are:
- High-energy particle acceleration processes in the context of
(proto)-stellar flares, pulsars, extragalactic jets and cosmic
- Plasma heating in, e.g., (proto)stellar coronae, galactic
high-velocity clouds and the interstellar medium,
- The generation, reconfiguration, filamentation and energy
conversion of magnetic fields in (proto)galaxies, accretion disks,
active galactic nuclei.
Our analytical and numerical
investigations are carried out on the grounds of the (multi)fluid-
as well as the kinetic plasma theory.
Example PhD issue:
- TeV Emission from Active Galactic Nuclei
More details about the USM Plasma-Physics group can be found at:
In the Centaurus A X-ray jet high-energy particles are continuously
accelerated on kpc length scales up to Lorentz factors of some
Young Stars and Star Formation
The Young Stars & Star Formation group at the USM is involved in the research of
individual young stars and whole star forming regions at
optical, infrared, X-ray, and sub-mm wavelengths.
Senior group member is
Prof. Th. Preibisch.
Topics of special interest to our group are:
- Infrared Interferometry.
- X-ray Studies of Young Stars.
- Stellar Populations and Triggered Star Formation in OB Associations.
PhD projects can be offered in the following fields:
- Stellar Feedback and Triggered Star Formation in OB Associations:
The interaction of the strong winds and the ionizing
radiation from massive stars can destroy surrounding clouds,
but, in the right circumstances, it can also trigger
secondary star formation by compressing the clouds and
driving them into collapse. The group is actively involved
in an international cooperation that performs a
comprehensive multi-wavelength study of the massive young
clusters in the Carina Nebula. Deep surveys in the X-ray,
near-infrared, and sub-mm bands are currently performed. One
possible PhD project would be to contribute to the analysis
and interpretation of these new data.
- Infrared Interferometry of Young Stars:
Infrared Long-Baseline Interferometers such as the ESO Very
Large Telescope Interferometer can provide very high angular
resolution of down to the milli-arcsecond scale. This allows,
for the first time, to study the inner circumstellar regions
of young stellar objects with spatial resolution below 1 AU
and provides new and unique insight into the structure of
protoplanetary disks, accretion and outflow processes, and
on the multiplicity of the young stars.
More details about the USM Young Stars & Star Formation group can be found at:
Summary of results on the multiplicity of the Orion Trapezium
stars revealed by infrared interferometry.