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: 731754.0, MPI für Astronomie / Publikationen_mpia
The EMPIRE Survey: Systematic variations in the dense gas fraction and star formation efficiency from full-disk mapping of M51
Authors:Bigiel, F.; Leroy, A. K.; Jiménez-Donaire, M. J.; Pety, J.; Usero, A.; Cormier, D.; Bolatto, A.; Garcia-Burillo, S.; Colombo, D.; González-García, M.; Hughes, A.; Kepley, A. A.; Kramer, C.; Sandstrom, K.; Schinnerer, E.; Schruba, A.; Schuster, K.; Tomicic, N.; Zschaechner, L.
Date of Publication (YYYY-MM-DD):2016
Title of Journal:The Astrophysical Journal Letters
Volume:822
Issue / Number:2
Start Page:id. L26 (7 pp)
Audience:Not Specified
Abstract / Description:We present the first results from the EMPIRE survey, an IRAM large program that is mapping tracers of high-density molecular gas across the disks of nine nearby star-forming galaxies. Here, we present new maps of the 3 mm transitions of HCN, HCO+, and HNC across the whole disk of our pilot target, M51. As expected, dense gas correlates with tracers of recent star formation, filling the “luminosity gap” between Galactic cores and whole galaxies. In detail, we show that both the fraction of gas that is dense, {f}{dense} traced by HCN/CO, and the rate at which dense gas forms stars, {{SFE}}{dense} traced by IR/HCN, depend on environment in the galaxy. The sense of the dependence is that high-surface-density, high molecular gas fraction regions of the galaxy show high dense gas fractions and low dense gas star formation efficiencies. This agrees with recent results for individual pointings by Usero et al. but using unbiased whole-galaxy maps. It also agrees qualitatively with the behavior observed contrasting our own Solar Neighborhood with the central regions of the Milky Way. The sense of the trends can be explained if the dense gas fraction tracks interstellar pressure but star formation occurs only in regions of high density contrast.
Free Keywords:galaxies: individual: M51; galaxies: ISM; galaxies: star formation; ISM: molecules; radio lines: galaxies
External Publication Status:published
Document Type:Article
Communicated by:N. N.
Affiliations:MPI für Astronomie
Identifiers:ISSN:0004-637X %R 10.3847/2041-8205/822/2/L26
URL:http://cdsads.u-strasbg.fr/abs/2016ApJ...822L..26B
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.