Jeff Cooke

ARC Future Fellow - Centre for Astrophysics & Supercomputing
Swinburne University of Technology, PO Box 218, Mail number H30, Hawthorn, VIC 3122 Australia
office: +61 3 9214 5392 -- fax: +61 3 9214 8797 -- email:

AR 315

Lyman break galaxy interactions at z ~ 3

I am leading several related projects that investigate the observed and predicted behavior of close and interacting LBGs at z ~ 3. We are using deep Keck optical imaging and spectroscopic surveys (Cooke et al. 2005), deep Palomar and Large Binocular Telescope infrared spectroscopy, and an analysis of a high resolution hybrid numerical/analytical cosmological simulation (Berrier & Cooke 2011) to examine spectroscopic interacting galaxy pairs and spectro-photometric close pairs. Relationships found between spectroscopic properties and pair separation (Cooke et al. 2010) and the clustering behavior of LBG sub-types (Cooke & Omori 2011b, in prep.), is providing valuable insight regarding the morphological changes and triggered star formation LBGs encounter from interactions, connections between restframe UV and optical properties, the LBG merger rate, and implications on assembly histories from spectroscopic indicators. The discovery of the luminous LBG-2377 (image on right) has provided some key data for this work (Cooke et al. 2008b).

Click here to access the ADS link displaying a list of articles describing this work and other research of mine.



A false color (negative) image of interacting Lyman break galaxies (termed LBG-2377) comprise the brightest LBG at z ~ 3 known to date (Cooke et al. 2008). These "embryo" galaxies show evidence that they are merging and provide information on the physical properties and formation processes of galaxies about 11.4 billion years ago, when the universe was only 15% its current age.

LBGs, like those above, are visible because they are undergoing a burst of star formation. One cause of this burst may be the merging of galaxies, as is the case for the much closer galaxies NGC 4038 and NGC 4039 (image to the right) known as the Antennae Galaxies.

The Hubble Space Telescope

The Milky Way can be seen, as well as two of our closest companion galaxies, the Large and Small Magellenic Clouds, in this long-exposure image of the 4 meter telescope at the CTIO located in the Southern Hemisphere (Chile).
  Astronomy 110
Physics 20A  
  Physics 7D
Curriculum Vitae
  Astro Grad Seminar
Centre for Astrophysics & Supercomputing
  Caltech Astronomy Department
Center for Cosmology
UC Irvine
  Center for Astrophysics and Space Sciences
UC San Diego
W. M. Keck Observatory  
  Palomar Observatory