Anish M. Amarsi

Theoretical astrophysics
Department of Physics and Astronomy
Uppsala University
Box 516, 75120 Uppsala
Sweden
Email: anish.amarsi [at] physics.uu.se

Biography

I am a researcher at Uppsala University (since 2021; docent/habilitated since 2023). Before that, I was a postdoc here (2019 -- 2021), and before that I was a postdoc at MPIA in Germany (2016 -- 2019). Earlier, I was a PhD student at ANU in Australia supervised by Martin Asplund and Remo Collet (2013 -- 2016), and a BA/MSci student at the University of Cambridge in the UK (2009 -- 2013).

Research

The focus of my research is on improving the accuracy of models of the light that emerges from the atmospheres of stars like the Sun. By comparing these models against real observations of stars, we can infer their essential properties --- in particular, their chemical compositions. To a good approximation, the present-day chemical compositions of Sun-like stars reflect the compositions of the gas from which the stars formed at their respective times of birth. Thus, by studying stars of different ages and different orbits in this way, it we may learn about the history and evolution of our Galaxy and of the cosmos.

Keywords include:

Atomic processes
3D non-LTE radiative transfer
Spectroscopic models of late-type stars
The solar chemical composition
Stellar parameters and chemical compositions
Galactic chemical evolution

Movies

Solar surface convection with STAGGER -- Cis Lagae, University of Warwick.

Log of gas temperature in a vertical slice of a solar model atmosphere (red line shows the Rosseland mean optical depth unity).

3D non-LTE formation of the silver 328nm line in the solar atmosphere with BALDER (Caliskan et al. 2026).

Funding

My funding comes from the Swedish Research Council (currently via an individual Project Grant, Optimised 3D non-equilibrium models for accurate abundance analyses of the Milky Way halo, VR 2025-05167; formerly via an individual Starting Grant, Accurate compositions of Sun-like stars, VR 2020-03940) and the Royal Swedish Academy of Sciences (individual Crafoord Grant, The nature of neutron-star mergers via high-accuracy stellar abundances, CR 2024-0015).

Teaching and supervision

I am currently responsible for the Master's courses Cosmology and The Physics of Galaxies; and earlier I was responsible for The Physics of Stars and the Bachelor's course Astrophysics I. I (co-)supervise(d) several PhD students: Irene Amateis (Uppsala), Sema Caliskan (Uppsala; lead supervisor), Cis Lagae (Stockholm) Jack Mallinson (Stockholm), and Xudong Gao (MPIA). I also try to supervise one or two Bachelor's or Master's projects each year; feel free to reach out if you are interested in developing astrophysical methods and codes, or in running and analysing computer simulations, or in using these models to analyse and interpret observed stellar spectra!

Biography

Research

Movies

Funding

Teaching and supervision

Publications

PhD theses

Data

Other resources