Large-scale structure and future surveys: extracting information with multiple tracers

When: Wednesday, January 26, 2022, 3:30 PM - 4:30 PM
Where: Mile end campus

Speaker: Carol Guandalin (QMUL)

In this talk, I will present the work developed during my PhD, which first explores the relativistic anisotropies in the distribution of dark matter halos that emerge after connecting the observed redshift with its theoretical general relativistic (GR) prediction. I will focus on the power-spectrum dipole (2-point statistics) signal that appears in the cross-correlation of different halo populations (i.e. different dark matter tracers) obtained from a relativistic N-body simulation. In the second part of my talk, I will turn to the issue of mitigating the loss of redshift precision in photometric redshift surveys, the latter providing us with the large volumes required for the observation of these GR effects with highly dense samples. For that, I will present a novel method to calibrate photometric redshifts utilising the clustering information of both galaxies and neutral hydrogen intensity mapping at a three-point function level. I will show the ability of the bispectrum (3-point statistics) to recover the redshift distribution parameters when compared to the power spectrum, and also how this clustering-redshifts method depends upon the foreground contamination present in the neutral hydrogen maps.