Research Interests 

My research interests centre on the baryon cycle and its dependence on environment. I am fascinated by how galaxies accrete and expel gas, how feedback redistributes energy and material, and how these processes vary across filaments, nodes, sheets, and voids or evolve over cosmic time. The multiphase gas in the IGM, CGM and ISM is particularly interesting to study because it retains clear physical signatures of accretion, feedback and large-scale structure formation. I have worked with N-body and hydrodynamical simulations but am also interested in combining these with observational datasets especially as we are expecting exciting data from many new sky surveys and telescopes!

Below I describe some of my previous and ongoing research projects.

Dark Matter Substructure

My master’s dissertation focuses on studying the kinematic signatures left behind by dark matter substructure (subhalos) in dwarf galaxies. I am supervised by Dr. Eduardo Vitral and Prof. Jorge Penarrubia at the University of Edinburgh where I am a final year MPhys student.

I have been working on methods to identify captured stars in dwarf galaxies (in different subhalos) using two different method and analysing how the observable signatures may change depending on the size/mass of subhalos and other physical properties that can reveal more about the dark matter substructure in these galaxies.

On the left is a picture from my project that focuses on the most massive subhalo in the simulation alongside the position of other stars. The dotted line is its tidal radius and the grey stars are considered not captured. The pink stars, on the other hand, were classified as captured by my code which calculates their relative distance and total energy. The blue stars vs pink stars showed new stars being added from a previous time, or stars that conitnue to stay in between at least two simulation snapshot. I use the conditions that these stars must minimise energy with respect to the subhalo and also lie close enough. The plot is a way to ‘sanity check’ where the stars I classify as captured, are actually captured based on where their positions lie with respect to the subhalo’s tidal radius.

Galaxy Evolution

Over summer this year (2025), I was awarded the Carnegie Undergraduate Vacation scholarship which allowed me to join Dr. Marcin Glowacki’s research group, and the international collaboration ASymba that aims at studying gas asymmetries in galaxies.

I modelled 3D datacubes using the MOCHI software developed by Mathieu Cormier for galaxies from the Simba and Simba-C simulations. I used CAESAR to identify galaxies and galaxy properties on the basis of which I compared asymmetries. I measured 3D, 2D, and 1D asymmetries by either working with the datacube directly, collapsing it along the velocity axis for a 2D HI spatial map, or collapsing it along the X Y axes to work with the integrated 1D spectrum.

I found loads of interesting results that I am currently writing up, some of them include merging galaxies being more asymmetric, and the local environment of a galaxy (based on its projected surface density) to have little effect on its asymmetries which has made me more interested to see how different the case would be for large scale environments i.e. the positions of galaxies within sheets, filaments, nodes and voids.

On the right are some plots showing the mean asymmetry values for different types of galaxies as specified in the legend. I mostly compare them with MHI (HI mass of a galaxy) but found an interesting trend flip for satellites and centrals in Ms (stellar mass) vs MHI. This is likely a result of gas poor satellites making the cut in Ms which are likely to be more disturbed, MHI only allows for gas rich satellites and given their environment these are either satellites that haven’t been disturbed or are very compact (hence not very asymmetric).

Epoch of Reionisation

For my senior honours project/undergraduate dissertation at university, I worked with the Sherwood relics simulations on the epoch of reionisation. I modelled mock observations of fast radio bursts and their dispersion measures on the IGM for three different reionisation endpoints (top left).

Additionally, because the simulations model inhomogenous reionisation, I was able to naturally extract the scatter in dispersion measure and compare it to what we expect through simplfied analytical models that assume a homogenous process (bottom).

Here’s the full report for anyone interested:

https://www.mishitakhurana.com/s/SHP.pdf