Home News About Us Contact Contributors Disclaimer Privacy Policy Help FAQ

Home
Search
Quick Search
Advanced
Fulltext
Browse
Collections
Persons
My eDoc
Session History
Login
Name:
Password:
Documentation
Help
Support Wiki
Direct access to
document ID:


          Institute: MPI für Astronomie     Collection: Publikationen_mpia     Display Documents



ID: 731526.0, MPI für Astronomie / Publikationen_mpia
A portrait of cold gas in galaxies at 60 pc resolution and a simple method to test hypotheses that link small-scale ISM structure to galaxy-scale processes
Authors:Leroy, A. K.; Hughes, A.; Schruba, A.; Rosolowsky, E.; Blanc, G. A.; Bolatto, A. D.; Colombo, D.; Escala, A.; Kramer, C.; Kruijssen, J. M. D.; Meidt, S.; Pety, J.; Querejeta, M.; Sandstrom, K.; Schinnerer, E.; Sliwa, K.; Usero, A.
Date of Publication (YYYY-MM-DD):2016
Title of Journal:The Astrophysical Journal
Volume:831
Issue / Number:1
Start Page:id. 16 (33 pp)
Audience:Not Specified
Abstract / Description:The cloud-scale density, velocity dispersion, and gravitational boundedness of the interstellar medium (ISM) vary within and among galaxies. In turbulent models, these properties play key roles in the ability of gas to form stars. New high-fidelity, high-resolution surveys offer the prospect to measure these quantities across galaxies. We present a simple approach to make such measurements and to test hypotheses that link small-scale gas structure to star formation and galactic environment. Our calculations capture the key physics of the Larson scaling relations, and we show good correspondence between our approach and a traditional “cloud properties” treatment. However, we argue that our method is preferable in many cases because of its simple, reproducible characterization of all emission. Using, low-J 12CO data from recent surveys, we characterize the molecular ISM at 60 pc resolution in the Antennae, the Large Magellanic Cloud (LMC), M31, M33, M51, and M74. We report the distributions of surface density, velocity dispersion, and gravitational boundedness at 60 pc scales and show galaxy-to-galaxy and intragalaxy variations in each. The distribution of flux as a function of surface density appears roughly lognormal with a 1σ width of ∼0.3 dex, though the center of this distribution varies from galaxy to galaxy. The 60 pc resolution line width and molecular gas surface density correlate well, which is a fundamental behavior expected for virialized or free-falling gas. Varying the measurement scale for the LMC and M31, we show that the molecular ISM has higher surface densities, lower line widths, and more self-gravity at smaller scales.
Free Keywords:galaxies: ISM; galaxies: star formation; ISM: clouds; ISM: molecules; ISM: structure
External Publication Status:published
Document Type:Article
Communicated by:N. N.
Affiliations:MPI für Astronomie
Identifiers:ISSN:0004-637X %R 10.3847/0004-637X/831/1/16
URL:http://cdsads.u-strasbg.fr/abs/2016ApJ...831...16L
The scope and number of records on eDoc is subject to the collection policies defined by each institute - see "info" button in the collection browse view.