PhD position on Cosmology (M/F)

EURAXESS Czech Republic; Orsay; Sur place; EUR 45 000 - 65 000; Plein temps

Résumé du poste

The Irène Joliot-Curie Physics Laboratory of 2 Infinities (IJCLab) invites applications for a postdoctoral or research scientist position focused on cosmic microwave background data analysis in Orsay, near Paris.

You will use Simons Observatory data to extract the kinetic Sunyaev-Zeldovich signal from the CMB power spectrum, model it with local and reionization components, and collaborate with IJCLab and Berkeley teams to constrain early-Universe cosmology.

Responsabilités

• Use data from the Simons Observatory to extract the kSZ contribution from the CMB power spectrum.
• Model the kSZ signal as local and reionization components to derive cosmological constraints on the early Universe (~500 million years old).
• Collaborate with IJCLab and Berkeley CMB teams under supervision of senior researchers with IRL Centre support.

Description du poste

Offer Description

The Irène Joliot-Curie Physics Laboratory of 2 Infinities (IJCLab) is a UMR under the supervision of the CNRS (IN2P3), the University of Paris‑Saclay and the University of Paris. It is located on the campus of the University of Paris‑Saclay in Orsay, 20 km south of Paris, easily accessible by RER in 35 minutes.

IJCLab hosts about 560 staff members, including 340 engineers, technicians, administrators, 220 researchers and teacher‑researchers, and about 200 non‑permanent staff, including 120 doctoral students. The laboratory specializes in nuclear physics, high energy physics, theoretical physics, astroparticles, astrophysics and cosmology, particle accelerators, energy, environmental and health research.

In 2026 IJCLab will launch the first observing campaign of the cosmic microwave background (CMB) with the Simons Observatory Large Aperture Telescope, a 6‑metre primary mirror instrument featuring around 60,000 detectors—the largest array built to date.

The telescope will obtain new constraints on the standard cosmological model parameters and test extensions, requiring precise control of instrumental systematic effects and comprehensive modelling of astrophysical signals.

The focus of the project will be on characterizing the kinetic Sunyaev‑Zeldovich (kSZ) effect, which reports interactions between CMB photons and free electrons, providing insights into velocity fields of the recent Universe and the epoch of reionization.

Responsibilities

• Use data from the Simons Observatory to extract the kSZ contribution from the CMB power spectrum.
• Model the kSZ signal as local and reionization components to derive robust cosmological constraints on the early Universe around 500 million years old.
• Collaborate with the CMB team at IJCLab and the Berkeley team (James Bartlett, Simone Ferraro) under the supervision of Thibaut Louis and Léo Vacher, with support from the IRL Centre Pierre Binétruy.

Equality, diversity and inclusion

IJCLab bases its recruitment policy on the promotion of equality, diversity, and inclusion.