Akanksha Kapahtia

Visiting Fellow
Email: akapahtia [at] ncra.tifr.res.in
Phone: 020-2571 9218
Extn: 9218
Office: 218A
National Centre for Radio Astrophysics
Tata Institute of Fundamental Research
Savitribai Phule Pune University Campus,
Pune 411 007
Maharashtra, INDIA

Main Research Areas: Cosmology; The Epoch of Reionization; HI 21cm cosmology; Large-scale structure of the universe; Topological data analysis


Akanksha completed her B.Sc. in Physics and Electronics from the Department of Physics, Panjab University, Chandigarh, in 2011, and her M.Sc. in Physics from the Department of Physics and Astrophysics, University of Delhi, in 2013. She joined the Joint Astronomy Programme of Indian Institute of Science, Bengaluru, for a Ph.D. in 2014, working with Pravabati Chingangbam of the Indian Institute of Astrophysics on real-space statistical tools for 21cm cosmology. She obtained her Ph.D. degree in November, 2020, and then moved to NCRA-TIFR in December 2020 as a post-doctoral fellow.

Research description:

The spin flip 21cm transition of the neutral hydrogen atom is an important probe of cosmology at high redshifts (z>6) as it serves as a direct probe of an important phase transition of the Universe called the Epoch of Reionization (EoR). The power spectrum of the 21cm brightness temperature will be measurable with upcoming radio interferometers such as the Square Kilometre Array (SKA). The SKA would also have imaging capabilities at this epoch. The highly non-Gaussian nature of this signal requires one to explore statistical techniques which go beyond the usual 2-point statistics-based power spectrum. So far my work has focussed on employing real-space morphological descriptors called Minkowski tensors and topological quantities called Betti numbers to infer the prospects of constraining global properties of luminous sources during EoR from interferometers like the Square Kilometre array. Broadly, my research interest focusses on employing topological statistics to cosmological data sets to address questions ranging from structure formation and evolution in the Universe to disentangling primordial physics from late-time astrophysics.

Selected publications:

1. Morphology of 21cm brightness temperature during the Epoch of  Reioinization using Contour Minkowski Tensor,  (Akanksha Kapahtia et al. 2019, JCAP, 9, 053)

2. A novel probe of ionized bubble shape and size statistics of the epoch of reionization using the contour Minkowski Tensor, (Akanksha Kapahtia et al. 2018, JCAP 10, 011)