5 papers
Tracking ionization balance in intergalactic medium and its implications towards metallicity
Bhaskar Arya, Kartick C. Sarkar, Shiv K. Sethi
Ionization balance in the intergalactic medium (IGM) is central to the interpretation of quasar absorption spectra, linking observed ionic columns to the underlying gas density, te…
A Bayesian estimator for peculiar velocity correction in cosmological inference from supernovae data
Ujjwal Upadhyay, Tarun Deep Saini, Shiv K. Sethi
The peculiar motion of the host galaxies introduces bias in estimating cosmological parameters from supernova data. The coherent component of the peculiar motion is usually correct…
Cosmological constraints on mass-varying dark matter
Amlan Chakraborty, Anirban Das, Subinoy Das +1
As one of the fundamental unknowns of our Universe, the mass of dark matter remains to be a topic of great interest. We consider the possibility of a time-variation of the dark mat…
Cosmological consequences of statistical inhomogeneity
H. V. Ragavendra, Dipayan Mukherjee, Shiv K. Sethi
A space-dependent mean for cosmological perturbations negates the ansatz of statistical homogeneity and isotropy, and hence ergodicity. In this work, we construct such a primordial…
Thermal Evolution of the IGM due to Lyman-α photons during the Cosmic Dawn
Janakee Raste, Anjan Kumar Sarkar, Shiv K. Sethi
The first star-forming objects which formed at high redshifts during the cosmic dawn (CD) also emitted photons between Lyman- and Lyman-limit frequencies. These photons are ins…