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Bachelor’s & Master’s thesis projects
at the University Observatory
Bachelor’s thesis topics of the Extragalactic Astronomy Group
on machine learning, instrumental and observational (Wendelstein) projects,
stars and planets, galaxies, gravitational lensing and cosmology
can be found
→ here.
Please also check out the master’s thesis projects, and let us know which
would interest you, because they may in part be split and downgraded
to fit into a bachelor’s thesis.
Master’s thesis topics of the Extragalactic Astronomy Group
on machine learning, instrumental and observational (Wendelstein) projects,
stars and planets, galaxies, gravitational lensing and cosmology
can be found
→ here.
1. Instrumentation and observational projects
With the upcoming Square Kilometre Array (SKA) and its precursor
telescopes, radio astronomy is undergoing a renaissance.
New algorithms, data reduction methods and survey modes are actively
developed to handle the EB-scale raw data streams produced and to
utilise the full potential of these new instruments.
As part of a large collaboration, our group at LMU is developing
commensal line intensity mapping and interferometric imaging using
scanning observations.
Such interferometric scanning or on-the-fly (OTF) observations are
increasing the survey speed by removing the settle-and-slew overhead
while also enabling commensal single-dish intensity mapping, providing
a dramatic improvement in data acquisition efficiency.
However, the scanning motion of the antennae pointing relative to the
delay centre introduces smearing effects that need to be corrected
in the imaging process.
In particular, the smearing of the primary beam (PB) response
introduces flux-density errors in the interferometric images.
This project aims to model the smeared PB by measuring the flux-density
variation of thousands of sources detected in our pilot MeerKAT OTF
observations.
The developed PB models and software will be incorporated into our OTF
imaging pipeline, which we will use to reduce 100+ hours of MeerKAT
OTF data observed in the upcoming year by our collaboration.
2. Stars and planets
Project 2.1 (Master’s project):
Multi-wavelength observations of star formation regions
(T. Preibisch preibisch@usm.lmu.de)
Students can carry out investigations as part of an ongoing project,
e.g., correlation of object lists in different wavelengths ranges
(from X-ray to the sub-mm regime).
3. Galaxies and AGN
Project 3.1 (Bachelor’s project):
Dynamos in galaxies
(H. Lesch lesch@usm.lmu.de)
All galaxies are magnetized. Where do galactic magnetic fields come
from, how are they maintained and how are they structured? These are
the questions we wish to answer. In this project we will develop
a model for the amplification of galactic magnetic fields based on
analytic calculations.
Project 3.2 (Bachelor’s project):
Propagation of cosmic rays in the Galaxy
(H. Lesch lesch@usm.lmu.de)
Cosmic rays represent a small but high-pressure part of the
interstellar medium. Through their pressure on the magnetic fields,
cosmic rays contribute considerably to the galactic dynamo. In this
project we will analyse the properties of Galactic cosmic rays and
their impact on gamma-ray emission.
Astronomers noticed more than 100 years ago that the galaxy
populations within dense galaxy clusters are different from those
in the surrounding low-density field, but the underlying reasons
remain unclear.
Hierarchical structure formation leads dense clusters to form rather
late in the Universe and to continue the accretion of surrounding
material, including star forming spiral galaxies where through a
range of processes they are transformed into ellipticals or S0s.
Studies over the past decades have clarified the range of physical
processes that are likely contributing to this transformation, and
these include ram pressure stripping, mean field tidal stripping and
galaxy merging, among others.
We are using a new Sunyaev-Zel’dovich effect selected
sample of galaxy clusters from SPT that extends to redshift
z ~ 2 together with data from the DES, Spitzer, and
Herschel to study these galaxy population transitions as a function
of cosmic time.
The goal of this project is to use the multi-band optical and
IR photometry to identify cluster galaxies and study the transition
in color and star formation rates as a function of radius from the
cluster center as well as a function of cosmic time and cluster mass.
Our dataset is uniquely suited for this study, because we have a well
understood sample of clusters extending over a broad redshift range
and a uniform photometric imaging dataset in the optical and IR over
large areas of the sky.
Project 3.4 (Master’s project):
Exploring the dark side of galaxy formation and evolution using radio continuum data
(J. Mohr Joseph.Mohr@physik.lmu.de)
Among the many facets under investigation of the galaxy formation
and evolution puzzle, two old and still unanswered questions remain
at the core of our incomplete picture:
- How do galaxies grow their stellar mass over cosmic time?
Answering this question has proven difficult mainly because of the
uncertainties in estimating the on-going star formation for large,
representative galaxy samples.
The easily accessible ultra-violet (UV) restframe emission, in
principle a direct probe of the young short-lived massive stellar
populations, is in fact measuring only the small fraction of that
emission that has not been absorbed by the interstellar dust.
It thus needs to be corrected by factors that, depending on the
intrinsic galaxy properties, can vary by orders of magnitude.
- Why does star formation cease at a certain point during the
galaxy life?
In the last decade many studies have agreed in assigning a relevant
role to nuclear activity (AGNs, due to massive black hole growth)
in affecting the galaxy star formation histories (SFHs).
In particular, once a major burst of star formation has eventually
exhausted the gas inside the galaxy immediately available for star
formation, the so-called “radio-mode feedback” is often
invoked as preventing the gas in the outer galaxy halo from cooling
and starting star formation again.
Deep radio surveys, conducted in association with multi-wavelength
observations, allow us to probe at the same time dust-unbiased star
formation and nuclear activity, and hence have become a fundamental
tool in the last decade for studying galaxy evolution.
This master project will focus on already available JVLA radio
continuum data in the deepest extra galactic fields in order to
obtain a dust-unbiased view of star formation over cosmic time
and a first-order estimate of radio-AGN feedback to be compared
to theoretical model expectations at different redshifts and halo
masses.
The observed bimodal distribution of local Universe galaxies in
star formation properties (from optical color-magnitude and stellar
mass-star formation rate diagrams) is due to the process of star
formation quenching, making once star forming spiral galaxies to
non/little star forming elliptical/S0 galaxies.
There are many possible processes responsible for this observed star
formation quenching, among which ram-pressure stripping is the dominant
mechanism in dense galaxy cluster environment.
The hot
(107 . . . 108 K)
and dense
(ne ~ 10−4 . . . 10−2 cm−3)
intracluster medium can strip cold gas from the spiral galaxy disk,
which eventually truncates star formation as the galaxy moves though
the cluster environment.
We have acquired ultraviolet data for a sample of galaxies undergoing
ram-pressure stripping (with tentacles of star formation along the
stripped tails with the galaxy disk resembling a jellyfish) where
the ongoing truncation of star formation can be directly studied
comparing with emission line diagnostic maps made from MUSE IFU data.
This project involves studying the star formation progression in a
galaxy undergoing ram-pressure stripping with indications of truncation
along the galaxy disk.
There are opportunities to collaborate with a larger team involved
in multiwavelength analysis of jellyfish galaxies.
Project 3.6 (Bachelor’s project):
Single tidal disruption events around Supermassive Black Holes (literature-based)
(P.D. Dr. Roberto Saglia saglia@mpe.mpg.de)
Stars passing too near the central supermassive black holes of
galaxies can be tidally disrupted, causing a brightening of the
centers, followed by a declining light curve with characteristic
shapes and time scales measurable at different wavelenghts, from
X-rays to UV and the optical bands, depending on masses of the BHs.
Project 3.7 (Bachelor’s project):
Recurrent tidal events around Supermassive Black Holes (literature-based)
(P.D. Dr. Roberto Saglia saglia@mpe.mpg.de)
A subclass of tidal events around Supermassive Black Holes are recurrent:
the brightening of the measured light curve repeats on quasi-periodic time
scales. This happens every time a star orbiting a SMBH hits its accretion
disk.
Project 3.8 (Bachelor’s project):
High-redshift galaxies, Little Red Dots and Black Holes (literature-based)
(P.D. Dr. Roberto Saglia saglia@mpe.mpg.de)
Thanks to the James Webb Space Telescope 'primordial' galaxies can be
detected up to very high redshifts. Some of them are identified as
'Little Red Dots', characterized by high stellar masses and possibly
large amounts of dust, small sizes, V-shaped spectra. Their broad
emission lines point to the presence of accreating supermassive black
holes. They probe models of galaxy formation and evolution and play an
important role in defining the epoch of reionization.
Project 3.9 (Master’s project):
Diffuse Lyman-Alpha Emission in the Cosmic Web with VIRUS
(Dr. Max Fabricius mxhf@mpe.mpg.de,
P.D. Dr. Roberto Saglia saglia@mpe.mpg.de)
This project exploits the deepest VIRUS dataset currently in existence
to search for and characterise diffuse Lyman-alpha emission in the
high-redshift universe. VIRUS is an integral field unit (IFU)
spectrograph — an instrument that simultaneously records a spectrum at
every spatial position across an extended field of view — and the
available data surpasses existing IFU surveys by orders of magnitude
in areal coverage. The core science goals are the detection,
characterisation, and statistical description of diffuse Lyman-alpha
emission; the characterisation of individual Lyman-alpha emitting
galaxies in the field; and comparison of the results with cosmological
simulations and with existing and forthcoming IGM tomography datasets
mapping the three-dimensional large-scale structure of the universe.
Project 3.10 (Master’s project):
Secondary Nuclei and Recoiling Black Hole Candidates in Euclid Early-Type Galaxies
(Dr. Max Fabricius mxhf@mpe.mpg.de,
P.D. Dr. Roberto Saglia saglia@mpe.mpg.de)
This project uses the first systematic sample of secondary nuclei in
early-type galaxies identified by the Euclid Space mission to
investigate the physical nature and origin of these compact,
off-centre sources. The core of the project is a photometric and
structural characterisation of the sample, with the goal of
distinguishing between formation scenarios such as minor mergers,
stripped satellite cores, or gravitationally recoiling supermassive
black holes. Depending on the results, the project may extend to
spectroscopic follow-up observations to measure stellar kinematics and
dynamical masses, placing the findings at the intersection of galaxy
evolution, observational dynamics, and the electromagnetic signatures
of massive black hole mergers.
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.
4. Cosmology, large-scale structure, and gravitational lensing
Project 4.1 (Bachelor’s project):
Distances to supernovae in various cosmological models
(J. Weller weller@usm.lmu.de)
The student will derive the correlation between distance and red shift
for different Friedmann Models. Boundary conditions to cosmological
parameters will be derived by comparison with supernova data. These
analyses are made with the aid of so-called Monte Carlo Markov chains.
If there is enough time, the analysis can be extended to models with
extra dimensions.
Project 4.2 (Master’s project):
Comparing simulated and observed red-sequence clusters
(K. Dolag dolag@usm.lmu.de)
The majority of galaxies in clusters are “red” galaxies (S0
or elliptical galaxies), i.e., galaxies with no ongoing star formation.
This makes them form a “red sequence” in color-magnitude
space.
In multi-band photometric surveys (e.g., the Dark Energy Survey DES)
one sucessfully identifies clusters of galaxies by their red-sequence
galaxy population, and estimates the (photometric) redshifts for
clusters using the colors of their red galaxies.
The number of red galaxies of each cluster is used to define its
“richness” (a quantity strongly related to the total mass
of the cluster).
For many purposes in cosmology one would like to relate the
observationally identified “red sequence clusters” to
clusters numerically simulated within the framework of structure
formation.
For example, one would like to know how cluster mass and cluster
richness scales, what the scatter is, and how much dark matter
is associated with individual red galaxies (as a function of the
luminosity and position within the cluster).
The goal of this project is to apply the observers’
cluster-finding technique to simulated clusters and to derive a
catalog with cluster richness, their red-sequence member galaxies,
and dark matter halo masses of individual member galaxies.
These findings can then be compared to results from observations or
can be used to predict the outcome of ongoing and future observations.
One of the leading methods for studying the cosmic acceleration,
measuring neutrino masses and directly measuring the growth rate
of cosmic structures is through studies of the redshift and mass
distribution of uniformly selected samples of galaxy clusters.
A key element of these studies is constraining the masses of the
galaxy clusters using information from weak gravitational lensing.
The goal of this project is to use the available weak gravitational
lensing mass information from the Dark Energy Survey within
samples of galaxy clusters selected from the South Pole Telescope
Sunyaev-Zel’dovich effect survey or the RASS (and soon from eROSITA!)
X-ray survey to study the cosmic acceleration, neutrino masses, and
the growth rate of cosmic structures.
- Understand the impact of surrounding large-scale structure and
miscentering on the weak-lensing mass estimates of galaxy clusters.
Application to real cluster sample with DES shear catalogs to
constrain masses.
- Understand the impact of contaminating impacts due to X-ray
and radio AGN on the selection and cosmological analysis of galaxy
cluster samples.
- Measure correlations among cluster observables in the X-ray,
SZE, and optical and study their impact on cosmological analyses.
Projects in the Astrophysics, Cosmology, and Artificial Intelligence Group
(Daniel Grün et al.)
Projects in the Physical Cosmology Group
(Jochen Weller et al.)
Projects in the Astrophysics, Cosmology, and Artificial Intelligence Group
(Daniel Grün et al.)
Projects in the Physical Cosmology Group
(Jochen Weller et al.)
5. 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 disks, 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 disks.
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 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 disks, 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.
Past and ongoing Bachelor’s and Master’s thesis 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 astrophysics:
- 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 centers (active galactic nuclei, origin and
nature of the gas cloud G2 near the Galactic center)
- 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
protoplanetary disks)
- 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 projects
as well as more detailed information on ongoing research can be
found on the web pages of the
Computational Astrophysics Group.
6. High-energy astrophysics
X-ray and gamma-ray observations have been instrumental in enabling
scientists to study some of the most extreme cosmic sources in the
Universe.
The utilisation of data obtained through X-ray and imaging atmospheric
Cherenkov telescopes facilitates the comprehension of physical
processes in these extreme environments and the tracing of their
evolution.
This provides opportunities to study processes at the frontier of
known physics.
The research undertaken by our group encompasses a broad spectrum
of enquiry into astrophysics and fundamental physics, including the
investigation of cosmic-ray acceleration processes and the quest to
comprehend the nature of Dark Matter.
Those interested in pursuing this field are invited to get in touch.
Project 6.1 (Master’s project):
Multi-wavelength study of blazars
(Gayoung Chon gchon@usm.lmu.de)
We invite motivated students with a strong interest in high-energy
astrophysics and data analysis to apply for a thesis project centred
on blazars – the brightest and most variable active galactic
nuclei observed in the very-high-energy (VHE) gamma-ray sky.
The project focuses on a comprehensive multi-wavelength analysis
of blazers, utilising data from a range of instruments spanning the
electromagnetic spectrum.
A key emphasis is placed on data from Imaging Atmospheric Cherenkov
Telescopes (IACTs), particularly the MAGIC (Major Atmospheric Gamma
Imaging Cherenkov) telescopes.
Students will acquire and apply advance data analysis techniques,
investigating correlations between gamma-ray, X-ray, optical and radio
observations with a goal is to constrain and interpret the physical
parameters driving the emission processes of this extraordinary class
of objects.
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