Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published November 2011 | Published
Journal Article Open

The WiggleZ Dark Energy Survey: high-resolution kinematics of luminous star-forming galaxies

Abstract

We report evidence of ordered orbital motion in luminous star-forming galaxies at z~ 1.3. We present integral field spectroscopy (IFS) observations, performed with the OH Suppressing InfraRed Imaging Spectrograph (OSIRIS) system, assisted by laser guide star adaptive optics on the Keck telescope, of 13 star-forming galaxies selected from the WiggleZ Dark Energy Survey. Selected via ultraviolet and [O ii] emission, the large volume of the WiggleZ survey allows the selection of sources which have comparable intrinsic luminosity and stellar mass to IFS samples at z > 2. Multiple 1–2 kpc size subcomponents of emission, or 'clumps', are detected within the Hα spatial emission which extends over 6–10 kpc in four galaxies, resolved compact emission (r < 3 kpc) is detected in five galaxies and extended regions of Hα emission are observed in the remaining four galaxies. We discuss these data in the context of different snapshots in a merger sequence and/or the evolutionary stages of coalescence of star-forming regions in an unstable disc. We find evidence of ordered orbital motion in galaxies as expected from disc models and the highest values of velocity dispersion (σ > 100 km s^(−1)) in the most compact sources. This unique data set reveals that the most luminous star-forming galaxies at z > 1 are gaseous unstable discs indicating that a different mode of star formation could be feeding gas to galaxies at z > 1, and lending support to theories of cold dense gas flows from the intergalactic medium.

Additional Information

© 2011 The Authors. Monthly Notices of the Royal Astronomical Society © 2011 RAS. Accepted 2011 July 11. Received 2011 July 11; in original form 2011 April 30. Article first published online: 19 Sep. 2011. We wish to thank M. Colless for three nights of Directors time on IRIS2. We would also like to thank Jim Lyke and Shelley Wright for their help recreating rectification matrices and Andy Green for helpful discussions on data reduction and kinematics. We thank the referee for very valuable comments. We wish to acknowledge financial support from The Australian Research Council (grants DP0772084 and LX0881951 directly for the WiggleZ project, and grant LE0668442 for programming support), Swinburne University of Technology, The University of Queensland and the Anglo-Australian Observatory. The WiggleZ survey would not be possible without the dedicated work of the staff of the Australian Astronomical Observatory in the development and support of the AAOmega spectrograph, and the running of the AAT. GALEX is a NASA Small Explorer, launched in 2003 April. We gratefully acknowledge NASA's support for construction, operation and science analysis for the GALEX mission, developed in cooperation with the Centre National d'Etudes Spatiales of France and the Korean Ministry of Science and Technology. Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. The authors wish to recognize and acknowledge the very significant cultural role and reverence that the summit of Mauna Kea has always had within the indigenous Hawaiian community. We are most fortunate to have the opportunity to conduct observations from this mountain.

Attached Files

Published - Wisnioski2011p16544Mon_Not_R_Astron_Soc.pdf

Files

Wisnioski2011p16544Mon_Not_R_Astron_Soc.pdf
Files (2.1 MB)
Name Size Download all
md5:526a8bbb69e2c3d2d1a3a7425cdd99a9
2.1 MB Preview Download

Additional details

Created:
August 22, 2023
Modified:
October 24, 2023