Research
Research Areas
From the radio whisper of cosmic dawn to the magnetic violence of the Sun — the questions CASSA's scientists pursue, and the people pursuing them.
The breadth of the work
Five areas, twelve scientists, one centre
CASSA's science is carried out by its two Directors and its Core and Associate Members — astronomers and physicists based at IUB and at leading institutions across the world. Their work, published in journals from MNRAS and ApJ to Nature Astronomy, clusters into five research areas. Each below names what every member actually does, with a key paper.
What we study
From cosmic dawn to the Sun's corona
Area 01 · 4 scientists
Cosmology & the Early Universe
How did the universe begin, what is it made of, and how fast is it expanding? CASSA attacks these questions from four directions at once — the radio whisper of the first hydrogen, the cosmic web traced by galaxies, the warped light of lensed quasars, and the steady beat of exploding stars.
Khan Muhammad Bin Asad
Director
Listens for the faint 21-cm radio signal from cosmic dawn and the Epoch of Reionization with LOFAR and MeerKAT, building the beam models that strip away the instrumental polarization leakage able to mimic the cosmological signal.
Key paper Polarization leakage in epoch of reionization windows – I. LOFAR observations of the 3C196 field 2015 · MNRAS
Tanveer Karim
Associate Member
Weighs dark energy and the growth of cosmic structure with the DESI survey — he designed its emission-line-galaxy selection and cross-correlated those galaxies with the Planck CMB-lensing map.
Key paper Cosmological constraints from the cross-correlation of Planck CMB lensing and DESI-like emission-line galaxies 2023 · MNRAS
Anowar Jaman Shajib
Associate Member
Turns gravitationally lensed quasars into cosmic clocks: his STRIDES time-delay analysis of DES J0408-5354 measured the Hubble constant to 3.9%, among the sharpest from a single lens.
Key paper STRIDES: a 3.9 per cent measurement of the Hubble constant from the strong lens system DES J0408-5354 2020 · MNRAS
Syed Ashraf Uddin
Director
Charts cosmic expansion and dark energy with Type Ia supernovae, and showed how a supernova's host galaxy biases its brightness — a key systematic for precision cosmology and the Hubble tension.
Key paper The Influence of Host Galaxies in Type Ia Supernova Cosmology 2017 · ApJ
Area 02 · 2 scientists
Galaxies & Their Environments
Galaxies are not islands. CASSA studies how they assemble their stars and structure across cosmic time, and how the groups and clusters they live in shape — and quench — their growth, from JWST snapshots of the young universe to billion-particle cosmological simulations.
Lamiya Ashraf Mowla
Associate Member
Traces galaxy growth from cosmic dawn to today with wide JWST and HST imaging, and led the discovery of the 'Sparkler' galaxy's compact sources as the most distant globular-cluster candidates yet found.
Key paper The Sparkler: Evolved High-redshift Globular Cluster Candidates Captured by JWST 2022 · ApJL
Syeda Lammim Ahad
Associate Member
Studies how galaxies quench inside groups and clusters, reading the faint intracluster light as a tracer of dark-matter halos with the Hydrangea and FLAMINGO simulations and surveys like KiDS and Euclid.
Key paper How to interpret measurements of diffuse light in stacked observations of groups and clusters of galaxies 2023 · MNRAS
Area 03 · 2 scientists
Black Holes, AGN & Accretion
At the hearts of galaxies and in stellar binaries, matter spiralling onto black holes powers the brightest engines in the cosmos. CASSA measures how these black holes feed, grow, and launch relativistic jets — across the full sweep of black-hole mass.
Tonima Tasnim Ananna
Associate Member
Measures how supermassive black holes grew across cosmic time; her 'Accretion History of AGN' population-synthesis model found that roughly half of nearby active black holes are hidden behind Compton-thick obscuration.
Key paper The Accretion History of AGNs. I. Supermassive Black Hole Population Synthesis Model 2019 · ApJ
Payaswini Saikia
Associate Member
Tracks accretion and jets in black-hole X-ray binaries from radio to X-ray, and established the optical 'fundamental plane of black hole activity' linking black holes across the mass scale.
Key paper The Fundamental Plane of black hole activity in the optical band 2015 · MNRAS
Area 04 · 2 scientists
Stars, Planets & the Sun
Why do stars have the masses they do, and how does our own star heat its atmosphere to millions of degrees? CASSA models the birth of stars and planets and decodes the magnetic violence of the solar corona.
Tabassum Shahriar Tanvir
Associate Member
Runs radiation-magnetohydrodynamic simulations to learn what sets the masses of stars — how radiation, protostellar outflows, and metallicity sculpt the stellar initial mass function — and now models magnetized planet-forming disks.
Key paper The metallicity dependence of the stellar initial mass function 2024 · MNRAS
Shah Mohammad Bahauddin
Associate Member
Attacks the coronal-heating problem with NASA's IRIS spectrograph; his Nature Astronomy study traced solar transient brightenings to magnetic reconnection — among the first complete evidence for nanoflare-scale heating.
Key paper The origin of reconnection-mediated transient brightenings in the solar transition region 2021 · Nature Astronomy
Area 05 · 2 scientists
Theoretical & Applied Physics
Underneath the observations lies physics — the mathematics of fields and gravity, and the engineering of light itself. CASSA's theorists probe quantum gravity and black-hole entropy, while its photonics work designs nanostructures that bend light for sensing and solar energy.
M Arshad Momen
Core Member
Works at the foundations of quantum field theory and gravitation; his studies of boundary 'edge states' in gravity show how degrees of freedom on a horizon can account for black-hole entropy.
Key paper Edge dynamics for BF theories and gravity 1997 · Physics Letters B
Mustafa Habib Chowdhury
Core Member
Designs metal nanostructures that steer light with FDTD electromagnetics — pioneering aluminum nanoparticles for ultraviolet biosensing, and now optimizing plasmonics for thin-film solar cells.
Key paper Aluminum Nanoparticles as Substrates for Metal-Enhanced Fluorescence in the Ultraviolet for the Label-Free Detection of Biomolecules 2009 · Analytical Chemistry
Infrastructure
The instruments and the machine
High-performance computing
Timaeus
CASSA's HPC — SLURM-scheduled with 3-2-1 backups, built to scale toward a supercomputing facility.
Campus observatory
IUB CORE
Campus Observatory for Research and Education: a rooftop facility with optical telescopes and the STAR Telescope.
Research observatory
IUB Observatory
A 0.5 m optical telescope in an autotracking dome at the Kaliakair campus.
Radio telescope
STAR Telescope
Small Transient Array Radio Telescope — CASSA's radio instrument.
Where we're going
Research roadmap
- 1 Build international collaborations for access to leading ground-based and space telescopes.
- 2 Secure research funding through grants from national and international sources.
- 3 Upgrade the HPC regularly to grow computing capacity.
- 4 Support IUB departments in recruiting A&A / SPSE faculty.
- 5 Promote postdoctoral research fellowships within CASSA.
- 6 Develop, with IUB, a PhD programme roadmap for A&A / SPSE.
- 7 Campaign for IUB CORE and the IUB Observatory at Kaliakair.
- 8 Advance Bangladesh's space economy and international mission partnerships.
- 9 Organize regular seminars, symposia, talks and conferences.
Who does the research
CASSA's scientific direction is reviewed by an external Scientific Advisory Board. The research itself is carried out by the two Directors, Core and Associate Members, Graduate Members, Research Affiliates, and student Research Assistants and Interns. Meet them on the People page, or browse the full output on Publications.