DYNAMO I: A Sample of Ha-Luminous Galaxies with Resolved Kinematics

Дата и время публикации : 2013-10-23T00:40:45Z

Авторы публикации и институты :
Andrew W. Green
Karl Glazebrook
Peter J. McGregor
Ivana Damjanov
Emily Wisnioski
Roberto G. Abraham
Matthew Colless
Robert G. Sharp
Robert A. Crain
Gregory B. Poole
Patrick J. McCarthy

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: 28 pages, 14 figures. Additional supplementary figure will be available from the Journal website. Accepted for publication in MNRAS
Первичная категория: astro-ph.GA

Все категории : astro-ph.GA, astro-ph.CO

Краткий обзор статьи: (abridged) DYNAMO is a multi-wavelength, spatially-resolved survey of local ($z sim 0.1$) star-forming galaxies designed to study evolution through comparison with samples at z~2. Half of the sample has integrated H-alpha luminosities of >$10^{42}$ erg/s, the typical lower limit for resolved spectroscopy at z~2. The sample covers a range in stellar mass ($10^9$-$10^{11}$ Msun) and star-formation rate (0.2-100 Msun/yr). In this first paper of a series, we present integral-field spectroscopy of H-alpha emission for the sample of 67 galaxies. We infer gas fractions in our sample as high as ~0.8, higher than typical for local galaxies. Gas fraction correlates with stellar mass in galaxies with star-formation rates below 10 Msun/yr, as found by COLDGASS, but galaxies with higher star-formation rates have higher than expected gas fractions. There is only a weak correlation, if any, between gas fraction and gas velocity dispersion. Galaxies in the sample visually classified as disc-like are offset from the local stellar-mass Tully-Fisher relation to higher circular velocities, but this offset vanishes when both gas and stars are included in the baryonic Tully-Fisher relation. The mean gas velocity dispersion of the sample is ~50 km/s, and V/sigma ranges from 2 to 10 for most of the discs, similar to ‘turbulent’ galaxies at high redshift. Half of our sample show disc-like rotation, while ~20 percent show no signs of rotation. The division between rotating and non-rotating is approximately…

Category: Physics