From Rings to Bulges: Evidence for Rapid Secular Galaxy Evolution at z ~ 2 from Integral Field Spectroscopy in the SINS Survey
Creators
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Genzel, R.1, 2
- Burkert, A.3
- Bouché, N.1
- Cresci, G.1
- Förster Schreiber, N. M.1
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Shapley, A.4
- Shapiro, K.2
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Tacconi, L. J.1
- Buschkamp, P.1
- Cimatti, A.5
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Daddi, E.
- Davies, R.1
- Eisenhauer, F.1
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Erb, D. K.6
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Genel, S.1
- Gerhard, O.1
- Hicks, E.1
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Lutz, D.1
- Naab, T.3
- Ott, T.1
- Rabien, S.1
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Renzini, A.7
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Steidel, C. C.8
- Sternberg, A.9
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Lilly, S. J.10
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1.
Max Planck Institute for Extraterrestrial Physics
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2.
University of California, Berkeley
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3.
Ludwig-Maximilians-Universität München
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4.
University of California, Los Angeles
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5.
National Institute for Astrophysics
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6.
Harvard-Smithsonian Center for Astrophysics
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7.
Osservatorio Astronomico di Padova
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8.
California Institute of Technology
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9.
Tel Aviv University
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10.
ETH Zurich
Abstract
We present Hα integral field spectroscopy of well-resolved, UV/optically selected z ~ 2 star-forming galaxies as part of the SINS survey with SINFONI on the ESO VLT. Our laser guide star adaptive optics and good seeing data show the presence of turbulent rotating star-forming outer rings/disks, plus central bulge/inner disk components, whose mass fractions relative to the total dynamical mass appear to scale with the [N II]/Hα flux ratio and the star formation age. We propose that the buildup of the central disks and bulges of massive galaxies at z ~ 2 can be driven by the early secular evolution of gas-rich proto-disks. High-redshift disks exhibit large random motions. This turbulence may in part be stirred up by the release of gravitational energy in the rapid "cold" accretion flows along the filaments of the cosmic web. As a result, dynamical friction and viscous processes proceed on a timescale of <1 Gyr, at least an order of magnitude faster than in z ~ 0 disk galaxies. Early secular evolution thus drives gas and stars into the central regions and can build up exponential disks and massive bulges, even without major mergers. Secular evolution along with increased efficiency of star formation at high surface densities may also help to account for the short timescales of the stellar buildup observed in massive galaxies at z ~ 2.
Additional Information
© 2008 The American Astronomical Society. Received 2008 April 13, accepted for publication 2008 July 7. We thank the staff of Paranal Observatory for their support. This work would have been impossible without the dedicated work of the ESOLGSF team at ESO,MPE and MPIA Heidelberg. We are grateful to Norm Murray, Eve Ostriker, and Chris McKee for enlightening discussions on star formation processes and to Avishai Dekel and an anonymous referee for valuable comments on the paper.Attached Files
Published - GENapj08.pdf
Files
GENapj08.pdf
Additional details
Identifiers
- Eprint ID
- 14293
- Resolver ID
- CaltechAUTHORS:20090524-210427908
Dates
- Created
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2009-09-02Created from EPrint's datestamp field
- Updated
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2021-11-08Created from EPrint's last_modified field