The Parker Instability in 3-D: Corrugations and Superclouds Along the Carina-Sagittarius Arm

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

29 pages, 12 figures, Latex, Accepted by the Astrophysical Journal

Scientific paper

10.1086/339725

Here we present three-dimensional MHD models for the Parker instability in a thick magnetized disk, including the presence of a spiral arm. The $B$-field is assumed parallel to the arm, and the model results are applied to the optical segment of the Carina-Sagittarius arm. The characteristic features of the undular and interchange modes are clearly apparent in the simulations. The undular mode creates large gas concentrations distributed along the arm. This results in a clear arm/inter-arm difference: the instability triggers the formation of large interstellar clouds inside the arms, but generates only small structures with slight density enhancements in the inter-arm regions. The resulting clouds are distributed in an antisymmetric way with respect to the midplane, creating an azimuthal corrugation along the arm. For conditions similar to those of the optical segment of the Carina-Sagittarius arm, it has a wavelength of about 2.4 kpc. This structuring can explain the origin of both HI superclouds and the azimuthal corrugations in spiral arms. The wavelength matches the corrugation length derived with the young stellar groups located in the optical segment of the Carina-Sagittarius arm. Keywords: Galaxy: kinematics and dynamics -- Galaxy: structure -- Instabilities -- ISM: clouds -- ISM: magnetic fields -- ISM: structure -- MHD

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

The Parker Instability in 3-D: Corrugations and Superclouds Along the Carina-Sagittarius Arm does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The Parker Instability in 3-D: Corrugations and Superclouds Along the Carina-Sagittarius Arm, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Parker Instability in 3-D: Corrugations and Superclouds Along the Carina-Sagittarius Arm will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-9458

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.