THE SINS SURVEY OF z {approx} 2 GALAXY KINEMATICS: PROPERTIES OF THE GIANT STAR-FORMING CLUMPS

Journal Article · Wed Jun 01 04:00:00 EDT 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/733/2/101· OSTI ID:21576732

Genzel, R; Foerster Schreiber, N M; Genel, S; Tacconi, L J; Buschkamp, P; Davies, R; Eisenhauer, F; Kurk, J ^[1]; Newman, S; Jones, T; Shapiro, K ^[2]; Lilly, S J; Carollo, C M ^[3]; Renzini, A ^[4]; Bouche, N ^[5]; Burkert, A ^[6]; Cresci, G ^[7]; Ceverino, D; Dekel, A ^[8]; Hicks, E ^[9]

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1. Max-Planck-Institut fuer extraterrestrische Physik (MPE), Giessenbachstr. 1, D-85748 Garching (Germany)
2. Department of Astronomy, Campbell Hall, University of California, Berkeley, CA 94720 (United States)
3. Institute of Astronomy, Department of Physics, Eidgenoessische Technische Hochschule, ETH Zuerich, CH-8093 (Switzerland)
4. Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, Padova, I-35122 (Italy)
5. Department of Physics and Astronomy, University of California, Santa Barbara, Santa Barbara, CA 93106 (United States)
6. Universitaets-Sternwarte Ludwig-Maximilians-Universitaet (USM), Scheinerstr. 1, Muenchen, D-81679 (Germany)
7. Istituto Nazionale di Astrofisica-Osservatorio Astronomico di Arcetri, Largo Enrico Fermi 5, I - 50125 Firenze (Italy)
8. Racah Institute of Physics, Hebrew University, Jerusalem 91904 Israel (Israel)
9. Department of Astronomy, University of Washington, Box 351580, U.W., Seattle, WA 98195-1580 (United States)

We have studied the properties of giant star-forming clumps in five z {approx} 2 star-forming disks with deep SINFONI AO spectroscopy at the ESO VLT. The clumps reside in disk regions where the Toomre Q-parameter is below unity, consistent with their being bound and having formed from gravitational instability. Broad H{alpha}/[N II] line wings demonstrate that the clumps are launching sites of powerful outflows. The inferred outflow rates are comparable to or exceed the star formation rates, in one case by a factor of eight. Typical clumps may lose a fraction of their original gas by feedback in a few hundred million years, allowing them to migrate into the center. The most active clumps may lose much of their mass and disrupt in the disk. The clumps leave a modest imprint on the gas kinematics. Velocity gradients across the clumps are 10-40 km s{sup -1} kpc{sup -1}, similar to the galactic rotation gradients. Given beam smearing and clump sizes, these gradients may be consistent with significant rotational support in typical clumps. Extreme clumps may not be rotationally supported; either they are not virialized or they are predominantly pressure supported. The velocity dispersion is spatially rather constant and increases only weakly with star formation surface density. The large velocity dispersions may be driven by the release of gravitational energy, either at the outer disk/accreting streams interface, and/or by the clump migration within the disk. Spatial variations in the inferred gas phase oxygen abundance are broadly consistent with inside-out growing disks, and/or with inward migration of the clumps.

• OSTI ID: 21576732
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 733; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
EVOLUTION
GALACTIC EVOLUTION
GALAXIES
GIANT STARS
GRAVITATIONAL INSTABILITY
INSTABILITY
MIGRATION
PLASMA INSTABILITY
STARS
VELOCITY