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Welcome!  My name is Emmet Golden-Marx.  I am a seventh year PhD Candidate in the Boston University Astronomy Department.

e-mail: emmetgm at bu.edu
phone: 518-441-9404

My research interests focus on galaxy evolution and galaxy cluster formation. I am currently working with Prof. Elizabeth Blanton at BU studying galaxy clusters and galaxy evolution using bent, double-lobed radio sources to identify high-redshift galaxy clusters as part of the COBRA survey.  Bent, double-lobed radio sources are unique as the bent nature of the AGN implies some gaseous medium needed to bend the lobes.  Since the galaxies in a cluster form at the same cosmic time, we’ll  determine a redshift estimate by identifying the red sequence in our galaxy clusters using data from the Discovery Channel Telescope (DCT) and the Spitzer Space Telescope.  Given our sample selection (little or no optical identification in the Sloan Digital Sky Survey (SDSS)), we are searching for high-redshift galaxy clusters.  My first paper on this work showed that many of our bent radio sources (at 0.3 < z < 2.2) are in red sequence clusters, but that the bent radio sources in our clusters need not be at the cluster center.  Additionally, by characterizing the likelihood of non-red sequence galaxies being in each cluster, we are able to further strengthen our confidence in this result.   Currently, I am analyzing the characteristics of the bent radio sources relative to the cluster populations.  In terms of my overall work on the COBRA survey, my goal is that by identifying the red sequence in our clusters and characterizing the cluster populations as a whole, we can trace the evolution of massive and faint galaxies on the red sequence to determine what, if any, biases our cluster sample has.  Additionally, I’m using the location of bent double-lobed radio sources in these clusters to trace what physical process creates the bent lobes.  Specifically, are these radio sources more commonly in cluster-cluster mergers at high redshift?

Additionally, I’m investigating bent, double-lobed radio sources that are found in poor galaxy groups, fossil groups of galaxies, or the interfilament medium.  Since most active galactic nuclei (AGN) feature radio lobes that are collinear, the bending of these radio lobes means that something must be responsible for the ram pressure necessary to bend the lobes.   While many of these bent, double-lobed radio sources are found in galaxy clusters, a fair amount are not.  From the existence of these bent, double-lobed radio sources, we can study the surrounding extragalactic environments.

I did my undergraduate work at Brown University (class of 2013).  During my time at Brown, I worked with Prof. Ian Dell’Antonio and received a NASA RI Space Grant (2012) and a Brown University Undergraduate Teaching and Research Award (UTRA, 2012).  Most of my research with Prof. Dell’Antonio focused on studying progenitors of fossil groups, working under the hypothesis that fossil groups form via a dry merger.

During summer 2012, I worked with Dr. Matt Ashby of the Harvard-Smithsonian Center for Astrophysics as an REU student on the Star Formation Reference Survey.  Most of my work centered on studying the star formation rates in the sample of galaxies in the local universe using far-Infrared observations from the Herschel Space Telescope with auxiliary observations from the AKARI satellite.  We used these observations, along with a wide range of other multi-wavelength observations to estimate an overall star formation rate for each galaxy.