Dr. Leah K. Morabito


Radio Astronomer and UKRI Future Leaders Fellow
Durham University

Welcome

Welcome


I am an astronomer using radio telescopes to answer fundamental questions on how super-massive black holes co-evolve with the galaxies in which they reside. My speciality is high-resolution imaging at low frequencies, using a Square Kilometre Array pathfinder telescope, the Low Frequency Array. I recently won a UKRI Future Leaders Fellowship to carry out a unique high-resolution, low-frequency radio survey using LOFAR to help advance our understanding on how AGN help shape galaxy evolution. I will hold this fellowship from November 2020 at the Centre for Extragalactic Astronomy and the Institute for Computational Cosmology, Durham University, where I am an Assistant Professor. Outside of work, I am an avid reader, I love to sew, and you can often find me in the countryside walking my dogs! Scroll down for more information on my research, qualifications, advocacy, and how to contact me.

Research


I focus on answering fundamental questions about active galactic nuclei (AGN) by investigating their radio properties, and using multi-wavelength information to place the radio information in context. I am a core member of the LOFAR Surveys Key Science Project, and a member of the MIGHTEE survey, which is already using MeerKAT, a Square Kilometre Array precursor, for early science. I am also a member of both the extragalactic and VLBI working groups for the Square Kilometre Array. On the multi-wavelength side, I look forward to the WEAVE-LOFAR survey, which will provide over a million spectra for LOFAR sources. My collaborations within these teams spread across Europe, South Africa, and include colleagues from the US and Australia.

The team
I currently supervise a PhD candidate, James Petley, who is investigating the origin of radio emission in Broad Absorption Line Quasars (BALQSOs). We work closely with Dave Alexander and his group. Previous MSc and summer students I supervised have worked on exploiting the LOFAR Surveys data. Check out the Gallery below for specifics on several recent studies I've done.


Active Galactic Nuclei (AGN)
A super-massive black hole exists at the centre of almost every massive galaxy. The gravitational potential of these black holes can power highly energetic phenomena which are observed on sub-galaxy to galaxy cluster size scales, across the entire electromagnetic spectrum; when we observe these phenomena we know these are active galactic nuclei (AGN). The basic picture of AGN that has emerged is of a black hole surrounded by an accretion disk, with a corona of hot gas, and the entire region is circled by a dusty torus. In some cases, AGN launch relativistic jets that extend far beyond the galaxy itself. But no matter how much energy an AGN outputs, the black hole powering it still remains a tiny part (both in physical size and total mass) of its host galaxy. Yet we see observational evidence for tight correlations between black hole properties and the general properties of galaxies, and we know from cosmological simulations of the Universe that some energy from AGN must help regulate galaxy growth; without it we are unable to reproduce observed galaxy populations. This suggests feedback between AGN and their host galaxies, but the huge range of size scales coupled with a wide range of energy transport options means the true nature of this feedback remains unknown.


Radio emission from AGN
A galaxy with an AGN can produce radio emission in multiple ways. The red/pink emission you see in the image on the left (a galaxy named Cygnus A) is from synchrotron emission which is observed at radio wavelengths. These relativistic jets extend far beyond the host galaxy (the small white blob at the centre) and can interact with their environment. Here you can see that they have tunnelled through the hot gas in the intra-cluster medium, which is traced by X-ray emission in blue. Large scale jets like these were thought to be rare, although recently LOFAR has revealed they may be more prevalent than we think, and they are not well modelled in simulations. While the majority of AGN don't have these kinds of jets, they can still produce fainter, small-scale radio emission in other ways. We know there will be some contribution from star formation, as supernova remnants leftover from the deaths of massive stars are ideal locations for cosmic rays to accelerate and produce synchrotron emission. But there is a portion of the faint radio emission from AGN that cannot be accounted for by star formation: is it small scale jets? Thermal radio emission associated with disk winds? Something we haven't thought about yet? High resolution radio observations for large samples will be crucial for understanding the origin of this extra radio emission.




Research Opportunities


As part of my UKRI Future Leaders Fellow work, I have hired a Postdoctoral Research Assistant (PDRA) and a PhD candidate in my research group, to start for the 2021/2022 academic year.

If you are interested in applying for a scholarship/fellowship to work in my group, please contact me.
An incomplete list of possible PhD fellowships: Chevening, Fulbright, Marshall, others listed on Durham website


Qualifications & CV


View full Curriculum Vitae

Search by orcid on ADS

PhD, Leiden University
October 2012 - September 2016
"Radio Galaxies at Low Frequencies: high spatial and spectral resolution studies with LOFAR"
Supervisor: Huub Rottgering

MSc, University of Oklahoma
September 2009 - May 2012
"Active Galactic Nuclei: from Supermassive Black Holes to Rare FeLoBALs"
Supervisor: Xinyu Dai

BSc, University of Michigan
September 2001 - April 2005
Double major in Physics and Astronomy

Advocacy


I am committed to helping promote gender equality in Physics. As an undergraduate at the University of Michigan, I was one of the three co-founders of the Society of Women in Physics (SWiP). As a fellow at Oxford, I served as the President of the Oxford Women in Physics Society, and served on the department's Equality and Diversity committee. I am also committed to helping promote racial equality in Physics, and am actively learning what steps I can take to make systematic changes in our community.
Here is an excellent talk series I recommend for everyone, whether or not they belong to an under-represented group: Astronomy in Colour Talk Series. I am not associated with the AiC organisation, but have attended as many of the talks as I can!

Let's Get In Touch!


Feel free to send me an email or find me on github or orcid!