Abstract Details
| Name: Dinesh V. Raut Affiliation: National Centre for Radio Astrophysics (NCRA-TIFR) Conference ID: ASI2018_1604 Title : Measuring the reionization 21cm fluctuations using clustering wedges. Authors and Co-Authors : Supervisor: Tirthankar Roy Choudhury (NCRA-TIFR) Abstract Type : Contributed Talk Abstract Category : General Relativity and Cosmology Abstract : Studying the Epoch of Reionization (EoR) is one of the main challenges in modern cosmology. The epoch can be studied by looking at statistical information in the redshifted 21cm line emitted from neutral hydrogen. Ideally one would like to study the epoch and constrain various astrophysical processes from it. Problem is presence of foregrounds which are several orders of magnitude larger than the signal and which render the extraction of cosmological information very very difficult. One way to deal with this is to isolate the foregrounds in k-space where, if spectrally smooth, they are confined to a wedge region. The power spectrum is then obtained by averaging over remaining portion of k-space. Such a procedure biases the measurement of power spectrum with respect to extent of wedge. I would talk about the prescription which can account for this bias. I would also talk about the expansion of the power spectrum in the basis of shifted Legendre Polynomials which is necessary if one seeks to isolate the anisotropic component of the signal from the isotropic one. In the end I would discuss how the prescription mentioned above can act as necessary correction when one wants to do model comparison in presence of the k-space wedge. |