Siegel der Universität

Universität zu Köln
Mathematisch-Naturwissenschaftliche Fakultät
Fachgruppe Physik

I. Physikalisches Institut

Resolving the disk structure in high-mass star forming regions

ALMA observations of the sources G35.20-0.74 and G35.03+0.35 have resolved disks around two massive stars. These observations are suited to study the structure of these disks and compare them with simulations.

Searching for disks and studying feedback in the high-mass star forming region G29.96-0.02

ALMA observations of the high-mass star forming complex G29.96-0.02 revealed a complex dense gas structure with velocity signatures commonly found in disks. The presence of disks around high-mass stars is a current topic of debate. Furthermore, this region is ideal to study radiative feedback from a nearby HII region and mechanical feedback via a well-collimated molecular outflow.

Chemistry of complex organic molecules in the Large Magellanic Cloud

ALMA observations of organic molecules have been conducted, and are being conducted in the current cycle.  The goal of the thesis is to investigate the formation of complex organic molecules under the conditions of the LMC using the chemical code Saptarsy, and to compare with observations.

Synthetic spectra from chemical calculations

The chemical code Saptarsy has been developed to calculate chemical evolution in star-forming regions.  It has the ability to calculate synthetic spectra that can be compared to observations, but this is a very time consuming process.  The thesis is about developing a faster, if less acurate, method based on XCLASS, and to apply this to a parameter study for typical star formation conditions.

Cosmic Ray interactions with ice mantles

The chemistry program Saptarsy has recently been improved to provide a realistic description of grain mantles.  One important physical aspect that is missing is a realistic interaction of cosmic rays with the mantle.  In this thesis, the idea is to include these mechanisms, based on laboratory experiments from the literature.

Polarization in NGC 6334

Polarization measurements in the NGC6334 star forming cloud have been conducted using the POLKA instrument on APEX  This will allow to trace the magnetic field direction.  In the thesis, the magnetic field shall be compared to mass flows traced by molecular observations of the cloud.

Shocks in hot cores

The program Saptarsy can be used to model spectra of astrophysical sources based on evolutionary chemical models.  This shall be done here for a parameter space, taking into account shocks that will provide an instantaneous release of the ice mantle at a random time.