165 citations · 583 across the 12 of their papers we have counts for
5 papers · 1 filter
Efficient Cosmological Parameter Estimation with Hamiltonian Monte Carlo
Amir Hajian
Traditional Markov Chain Monte Carlo methods suffer from low acceptance rate, slow mixing and low efficiency in high dimensions. Hamiltonian Monte Carlo resolves this issue by avoi…
Measuring Statistical Isotropy of CMB Anisotropy
Tarun Souradeep, Amir Hajian, Soumen Basak
The statistical expectation values of the temperature fluctuations and polarization of cosmic microwave background (CMB) are assumed to be preserved under rotations of the sky. We…
Testing Global Isotropy of Three-Year Wilkinson Microwave Anisotropy Probe (WMAP) Data: Temperature Analysis
Amir Hajian, Tarun Souradeep
We examine statistical isotropy of large scale anisotropies of the Internal Linear Combination (ILC) map, based on three year WMAP data. Our study reveals no significant deviation…
Unveiling Hidden Patterns in CMB Anisotropy Maps
Tuhin Ghosh, Amir Hajian, Tarun Souradeep
Bianchi VII_h models have been recently proposed to explain potential anomalies in the CMB anisotropy as observed by WMAP. We investigate the violation of statistical isotropy due…
Statistical Isotropy of CMB Polarization Maps
Soumen Basak, Amir Hajian, Tarun Souradeep
We formulate statistical isotropy of CMB anisotropy maps in its most general form. We also present a fast and orientation independent statistical method to determine deviations fro…