Samuel Farrens


I am a postdoc and new member of the CosmoStat team at CEA Saclay. I am working with Jean-Luc Starck and Fred Ngolè on PSF estimation.


Contact Information:
Phone: +33 01 69 08 83 77
Fax: +33 01 69 08 65 77
Email: samuel [dot] farrens [at] cea [dot] fr

Research Interests

Prior to joining the CosmoStat team my work was primarily focused on the optical detection and analysis of clusters of galaxies using photometric redshifts. During my PhD I developed a prototype friends-of-friends optical cluster detection algorithm that was further developed and optimised during postdoc positions in Barcelona and Trieste. I also developed serval metrics and analysis codes designed to compare the relative performance of various different cluster detection codes on Euclid mock galaxy simulations.

I am currently working on galaxy image deconvolution using regularisation techniques such as sparsity and low-rank approximation. The idea being to remove the effects of a point spread function (PSF) that varies as function of position on the sky. This is beneficial for projects like Euclid that aim to measure galaxy shapes to good accuracy.

List of publications.


  • 2007-2010: PhD in Astrophysics, University College London, London, UK.
  • 2003-2007: MSci in Astrophysics, University College London, London, UK.


  • 2013-2015: Postdoc, Osservatorio Astronomico di Trieste (INAF-OATS), Trieste, Italy.
  • 2010-2013: Postdoc, Institut de Ciències de l'Espai (ICE-IEEC), Barcelona, Spain.