My main research interests are (click for more details):
  • (Low-mass) Galaxy formation and evolution
The life cycles of dwarf galaxies illustrate many challenges to our current understanding of galaxy formation and evolution. While star formation histories of local dwarf galaxies are complex and varied, in general they appear to be regulated by stellar feedback in the form of supernovae and winds that heat and deplete the central reservoirs of cold gas required for continued star formation. In simulations of lower mass systems, feedback is predicted to eject gas out of the galaxy and into the halo, resulting in an episodic star formation history. Repeated bursts have been cited as the driving force behind intense feedback mechanisms that can change the dynamical profile of the systems by driving baryons out of the center of the halo on short timescales, which also displaces the dark matter from the center and creates a cored dark matter profile, potentially addressing one of the principal challenges to the standard ΛCDM cosmology.

Until recently, however, the progenitors of contemporary dwarf galaxies at high redshift could not be studied directly. In Maseda et al. 2014, we identify such a population and conclude that strong starbursts play an important role in their evolution. We also begin to constrain some of the relevant timescales involved in the bursts, postulating that the internal dynamics of the systems will stabilize and hence terminate star formation before the gas reservoir is depleted. Much work still remains in understanding these galaxies, particularly since variations in the strength, duration, and initial mass of these bursts will produce descendants displaying a wide range of masses, from present-day dwarf galaxies to potentially Milky Way-like systems.
Using MUSE, I study the restframe-ultraviolet spectra of high-redshift galaxies. Features in this part of the spectrum, such as the C III] and Lyman-alpha emission lines, provide a lot of information about the physical state of these young galaxies. This type of study is extremly powerful when combined with information from the restframe-optical region, which can be obtained with Hubble's WFC3 camera. A key strength to this approach is the un-targeted nature of both instruments, allowing us to get a clear view of the full population of galaxies.

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