Star Formation out of the Magnetised Interstellar Medium

• Applicant: Professor Dr. Robi Stefan Banerjee
• Subject Area: Astrophysics and Astronomy
• Term: from 2016 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 319967414

• Final Report Year: 2023

Final Report Abstract

In this project we studied the formation of molecular clouds out of the magnetised interstellar medium (ISM). As mentioned in the proposal, our general understanding is, that molecular clouds form out of the diffuse atomic medium, where those diffuse HI clouds are likely to be magnetically subcritical (i.e. the magnetic field will prevent collapse by self-gravity) in a strongly magnetised ISM. Hence, the question arises how and how quickly can magnetically supercritical cloud cores be assembled? This question was the main driver for the project and we could give a plausible answer: From numerical studies based on three dimensional magneto-hydrodynamic simulations we concluded that the main promoter for supercritical, star-forming clouds is the Parker Instability. The PI was already proposed some time ago by a number of authors as a driver for cloud formation, which we could confirm with our self-consistent numerical studies within this project. Those developments and research projects were mainly achieved by the employed postdoc Bastian Körtgen.

Publications

• Supernova feedback in molecular clouds: global evolution and dynamics. Monthly Notices of the Royal Astronomical Society, 459(4), 3460-3474.
  Körtgen, Bastian; Seifried, Daniel; Banerjee, Robi; Vázquez-Semadeni, Enrique & Zamora-Avilés, Manuel
  
• Deuterium fractionation and H2D+ evolution in turbulent and magnetized cloud cores. Monthly Notices of the Royal Astronomical Society, 469(3), 2602-2625.
  Körtgen, Bastian; Bovino, Stefano; Schleicher, Dominik R. G.; Giannetti, Andrea & Banerjee, Robi
  
• Magnetic suppression of turbulence and the star formation activity of molecular clouds. Monthly Notices of the Royal Astronomical Society, 474(4), 4824-4836.
  Zamora-Avilés, Manuel; Vázquez-Semadeni, Enrique; Körtgen, Bastian; Banerjee, Robi & Hartmann, Lee
  
• Star formation in evolving molecular clouds. Astronomy & Astrophysics, 605, A97.
  Völschow, M.; Banerjee, R. & Körtgen, B.
  
• The driving of turbulence in simulations of molecular cloud formation and evolution. Monthly Notices of the Royal Astronomical Society, 472(2), 2496-2503.
  Körtgen, Bastian; Federrath, Christoph & Banerjee, Robi
  
• Fast deuterium fractionation in magnetized and turbulent filaments. Monthly Notices of the Royal Astronomical Society, 478(1), 95-109.
  Körtgen, B.; Bovino, S.; Schleicher, D. R. G.; Stutz, A.; Banerjee, R.; Giannetti, A. & Leurini, S.
  
• On the shape and completeness of the column density probability distribution function of molecular clouds. Monthly Notices of the Royal Astronomical Society, 482(4), 5233-5240.
  Körtgen, Bastian; Federrath, Christoph & Banerjee, Robi
  
• The origin of filamentary star forming clouds in magnetized galaxies. Monthly Notices of the Royal Astronomical Society: Letters, 479(1), L40-L44.
  Körtgen, Bastian; Banerjee, Robi; Pudritz, Ralph E. & Schmidt, Wolfram
  
• Global dynamics of the interstellar medium in magnetized disc galaxies. Monthly Notices of the Royal Astronomical Society, 489(4), 5004-5021.
  Körtgen, Bastian; Banerjee, Robi; Pudritz, Ralph E. & Schmidt, Wolfram
  
• Structure and expansion law of H ii regions in structured molecular clouds. Monthly Notices of the Royal Astronomical Society, 487(2), 2200-2214.
  Zamora-Avilés, Manuel; Vázquez-Semadeni, Enrique; González, Ricardo F.; Franco, José; Shore, Steven N.; Hartmann, Lee W.; Ballesteros-Paredes, Javier; Banerjee, Robi & Körtgen, Bastian
  
• Molecular cloud formation by compression of magnetized turbulent gas subjected to radiative cooling. Monthly Notices of the Royal Astronomical Society, 493(3), 3098-3113.
  Mandal, Ankush; Federrath, Christoph & Körtgen, Bastian
  
• The relative orientation between the magnetic field and gas density structures in non-gravitating turbulent media. Monthly Notices of the Royal Astronomical Society, 499(4), 4785-4792.
  Körtgen, Bastian & Soler, Juan D.
  
• The turbulence driving parameter of molecular clouds in disc galaxies. Monthly Notices of the Royal Astronomical Society, 497(1), 1263-1274.
  Körtgen, Bastian
  
• The spatial power spectrum and derived turbulent properties of isolated galaxies. Monthly Notices of the Royal Astronomical Society, 505(2), 1972-1986.
  Körtgen, Bastian; Pingel, Nickolas & Killerby-Smith, Nicholas