Skip to main content

Analysis tools for
large-scale galaxy surveys

  • Gravitational lensing.
  • DESI map.

Developing and testing models of structure formation

This group is actively involved in developing models in order to account for nonlinear clustering, galaxy Biassing, and redshift space distortions.

Exciting and timely research in Cosmology

There are still many open questions that need to be understood to strengthen the foundation of our cosmological paradigm or change it altogether.

The scientific community has tackled these questions through large astronomical surveys that scan the way millions of galaxies distribute across huge volumes and well into the past, when the Universe was half its current age. We can then relate the distribution of galaxies to the aforementioned problems through the use of n-point correlation functions.

Several such surveys are ongoing, just finished or will start in the near future. Their common denominator is the unprecedented level of precision at which they will render the large scale structure of the Cosmos. In particular we highlight the Dark Energy Survey (DES), the Physics of the Accelerating Universe Survey (PAUS), the ESA/Euclid satellite and Dark Energy Spectroscopic Instrument (DESI). All of them are state-of-the-art surveys in which our group is actively involved, often leading science working groups.

DESI Quasar at z=6.53.


To best exploit the galaxy survey data we must model complex processes such as the nonlinear gravitational collapse of the dark matter, the way galaxies form and trace this matter field (galaxy biassing) and the contamination of derived redshifts from peculiar velocities (redshift space distortions). These represent some of the biggest obstacles in interpreting galaxy clustering data as well as weak gravitational lensing. We also need to have tools for a detailed control of different observational systematics and scientific pipelines to combine different observables.

The end product of the line of research, besides basic knowledge, is the integration and development of analysis tools for optimisation and combination of survey data.

Senior institute members involved

Meet the senior researchers who participate in this research line.

  • Martin Crocce

  • Fco. Javier Castander

  • Pablo Fosalba

  • Enrique Gaztañaga