Abstract Details
| Name: Protap Halder Affiliation: Raman Research Institute Bangalore Conference ID: ASI2025_549 Title : EFFECT OF DIPOLE MODULATION IN CMB IN ESTIMATING THE WEAK GRAVITATIONAL LENSING Authors and Co-Authors : PROTAP HALDER Abstract Type : Poster Abstract Category : Galaxies and Cosmology Abstract : There is a clear indication of Cosmic Hemispherical Asymmetry (CHA) from the inferences of the data captured by both Planck Mission and WMAP. Basically, in one hemisphere there are more fluctuations in compare with other hemisphere in the observed CMB Maps. This indicates a clear statistical isotropy violation which can be incorporated mathematically by introducing Bipolar Spherical Harmonics with BipoSH Multipole L = 1 . This mode(L=1) is known as Dipole Modulation in CMB Temperature map. In the standard Cosmology, CMB Temperature is considered to be Statistically Isotropic which contains its complete information in the CMB Temperature power spectrum. CMB Temperature is redistributed due Weak Gravitational Lensing while it is evolving in time by the effects of distributed matters which are gravitationally interacting with CMB photons. In Standard Cosmology , Projected Lensing Potential field is also considered to be statistically isotropic which contains its complete information in the lensing power spectrum. In my project , I am working with the power law in Dipole Modulation which is scale dependent. BipoSH Spectra is the generalization of power spectra which includes statistical non-isotropy. We have calculated the corrections in the BipoSH Spectra while introducing both the CMB Temperature and Weak lensing to be statistically non-isotropic in general. In the general expression, we have used a specific case of isotropy violation which is Dipole Modulation to estimate the effect of it on Weak Lensing field. I have made some computations and got some results and this research is under progress. We hope we will better estimate the weak lensing field by doing the corrections which will be valuable for further research in the field where Projected Lensing Potential field will be used. |