As of November 2012 I have moved to the Leibniz-Institut für Astrophysik in Potsdam to work with the Galaxies & Quasars group headed by Lutz Wisotski, and in particular to participate in the MUSE project.

My previous work was carried out within the high-redshift group headed by Andrew Bunker at the University of Oxford, where I did my DPhil in astrophysics as a Marie Curie research fellow in ELIXIR - a network associated with the NASA/ESA James Webb Space Telescope NIRSpec Instrument.

My research interests lie in galaxy formation and evolution, in particular the observational study of galaxies in the high redshift universe (z > 7). A lot of my work involves designing, undertaking and analysing follow-up spectroscopic surveys of high-redshift candidate galaxies which have been selected with Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) imaging, employing the Lyman Break technique. In particular, I search for the Lyman-alpha emission line in the spectra of these candidate galaxies, which I can use as a diagnostic to confirm the high redshift inferred from their broad-band colours, in so doing tackling the question of whether Lyman-alpha emerges in the early universe during an era when it is mostly opaque to this line.

For objects lying at such high redshifts, the Lyman-alpha line is redshifted to the IR region of the electromagnetic spectrum. In analysing this data, where any potential signal is very faint and the infrared background sky varies a lot over short time-scales, a lot of effort goes into developing optimal reduction techniques.

Tools of the trade

The observatories I use for this work are both space-based and ground-based. As has been mentioned above, the initial selection of the candidate galaxies is carried out using the Hubble Space Telescope's Wide Field Camera 3 (WFC3), which was installed on Hubble in 2009 to replace the Wide Field and Planetary Camera 2. Our objects are selected from fields such as the HUDF (Hubble Ultra Deep Field) and ERS (Early Release Science) targetted by the Hubble Space Telescope. You may read about some of the identified high-z galaxies using these methods in the papers available here and here. These galaxies are viewed at a time when the universe's hydrogen content was very neutral, so these galaxies are used as probes of the ionization state of the universe during its infancy. Of particular interest is the question of whether these first objects provided sufficient photons to reionize the universe. (You can read about this in the papers linked to above.)