Role of Polarization in 21 cm Surveys

Envoyé par mbucher 
Role of Polarization in 21 cm Surveys
mercredi 10 juin 2020 11:15:05
9 June 2020

DIM-ACAV PhD Opportunity

APC, Université de Paris - LPENS, Ecole Normale Supérieure, Paris, France

Role of Polarization in 21 cm Surveys

We are seeking the immediate recruitment a PhD student as part of the following project for which funding has recently been made available through the DIM-ACAV programme of the Region Ile-de-France.

21 cm BAO (Baryon Acoustic Oscillations) intensity mapping offers a promising new technique for improving constraints on the nature of the Dark Energy, one of the most important outstanding puzzles of contemporary Cosmology. In particular, this technique is well adapted to redshifts greater than one, where dark energy domination began and which is hardly accessible to ground-based optical surveys. Although the feasibility of this technique has been demonstrated in idealized studies, a successful practical implementation has yet to be proven. The student recruited will focus on developing optimal analysis techniques and in particular on mitigating the leakage from the polarized synchrotron emission from our own Galaxy into the sought extragalactic cosmological signal. This thesis will combine theory, analysis of Big Data, and simulation with application to the SKA (Square Kilometer Array)-precursor HIRAX experiment near the SKA site in South Africa, for which the first data will become available in late 2021.

This thesis will be co-supervised by Martin Bucher (Laboratoire Astroparticules et Cosmologie, Univerité de Paris) and François Boulanger (Laboratoire de Physique ENS, Ecole Normale Supérieure). The student recruited must have completed an M2 in the French system or an equivalent course in another country. The stipend includes both fees and living expenses. Applications or informal inquiries should be directed to both Martin Bucher ( and François Boulanger ( This opportunity will remain open until a suitable applicant has been selected.