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Faculty of Mathematics and Natural SciencesAstrophysik I.Physik

Theoretical Astrophysics group Cologne - TAC

Our research deals with the numerical modelling of the star formation process by means of high-performance, 3D, magneto-hydrodynamical (MHD) simulations. The simulations cover large spatial scales from ISM physics on kpc scales over molecular clouds on scales of 10 - 100 pc to star forming filaments on (sub-) pc scales and finally to protostellar discs and jets on scales of 10 - 1000 AU.

In our research group we use several tools like the (M)HD codes FLASH, GADGET, GANDALF, the astrochemical code KROME, 3D-PDR or radiative transport codes like RADMC-3D and POLARIS.

Prof. Dr. Stefanie Walch-Gassner is the head of the SILCC project (SImulating the life Cyle of molecular Clouds), a collaboration of several European astrophysical institutes, which has set the aim to model the formation, evolution, and dispersal of molecular clouds in 3D, MHD simulations with particular focus on a detailed astro-chemical modelling and the inclusion of various feedback processes.

Contact information:

  • Phone: (+49|0) 221 / 470 - 3497
  • Fax: (+49|0) 221 / 470 - 5162
  • Email: walch [at] ph1.uni-koeln.de

Consultation hours

upon agreement in Room 1.14, Building 312 

Monthly Highlight

Measuring the Velocity Dispersion of the Warm Neutral Medium of the Milky Way at Galactic Scale using the Code FLASH

Fig. 1  shows a movie of the projected density of one of the runs (A disk with a spiral perturbation with no self gravity) over one orbital time.

Fig. 2 shows a comparison of the measured velocity dispersion at different runs. Gaseous spiral arms in the ISM of the Milky Way drive a dispersion of up to ~9 km/s, which decreases with galactocentric radius and is relatively higher in the inter arms than inside the spiral arms. Shear, supernova remnants, and thermal instabilities do not appear to play a significant role in driving velocity dispersion at such scales.