Job offer

European Commission; France; Sur place; EUR 35 000 - 50 000; Plein temps

Résumé du poste

Une commission européenne propose un poste de Junior Chair en cosmologie au sein du CNRS. Ce poste consiste à se concentrer sur l'analyse des données de lentilles gravitationnelles, à collaborer sur des projets de recherche et à contribuer à des initiatives de science ouverte, en lien avec l'Université Sorbonne.

Prestations

Collaboration avec l'Université Sorbonne

Accès à des initiatives de science ouverte

Publications scientifiques

Possibilité de proposer des projets d'enseignement

Qualifications

• Titulaire d'un doctorat ou d'un diplôme équivalent.
• Compétences en analyse de données et cosmologie.
• Intérêt pour les projets internationaux.

Responsabilités

• Proposer un projet de recherche axé sur l'analyse des données de lentilles gravitationnelles.
• Développer et valider des estimateurs de cisaillement.
• Collaborer avec des laboratoires de recherche en région parisienne.

Connaissances

Analyse de données

Cosmologie

Lentilles gravitationnelles

Sensibilité aux théories de la gravité

Formation

Doctorat ou équivalent

Description du poste

Organisation/Company CNRS Department Direction des ressources humaines Research Field Physics Researcher Profile First Stage Researcher (R1) Country France Application Deadline 14 Jul 2025 - 23:59 (UTC) Type of Contract Other Job Status Full-time Hours Per Week 35 Offer Starting Date 23 Jun 2025 Is the job funded through the EU Research Framework Programme? Not funded by a EU programme Is the Job related to staff position within a Research Infrastructure? No

Offer Description

The standard model of cosmology (ΛCDM), established in the early 2000s, relies on two still-mysterious components: dark matter and dark energy. The latter, of unknown nature and repulsive properties, presents a major challenge, requiring precision tests on cosmic expansion and structure formation history. This second domain, still poorly constrained, is key to testing General Relativity and potential alternative theories of gravitation on large scales.

Several international projects aim to tackle this challenge, including two ground-based surveys (Rubin/LSST, DESI) and two space missions (Euclid and Roman). The LPNHE plays a central role, particularly in the Rubin project—an 8-meter telescope dedicated to the Legacy Survey of Space and Time (LSST), which will map the southern sky over a 10-year period starting in 2025. With strong involvement in the design and characterization of the Rubin camera sensors, the LPNHE team will leverage this data for groundbreaking studies on dark energy.

LSST will collect tens of thousands of Type Ia supernovae, enabling precise mapping of cosmic expansion. Additionally, analyzing correlations in supernova velocity at low redshift will help measure the growth rate of structures. However, LSST's primary focus remains on weak gravitational lensing, which provides access to the matter distribution and allows testing gravity at different scales. With its widely recognized expertise in sensors and test benches, the LPNHE is ideally positioned to maximize the scientific impact of weak lensing.

The Junior Chair at LPNHE will strengthen these efforts by combining weak lensing and galaxy clustering data from DESI to constrain dark energy and explore the foundations of modern cosmology.

The LPNHE team is involved in several major cosmological surveys, both photometric (LSST, ZTF, SNLS) and spectroscopic (DESI, eBOSS, BOSS), providing access to multiple probes sensitive to dark energy and gravity theories. These include weak lensing, redshift measurements, space distortions, peculiar velocities of nearby Type Ia supernovae, and the Hubble diagram of Type Ia supernovae.

The group has developed expertise covering the entire analysis pipeline, from the fine characterization of sensors to cosmological inference. This positions it ideally for making a significant impact on dark energy studies and gravity tests in the coming decade.

With LSST about to begin operations, strengthening the team is crucial to scaling up as the data arrives, developing LSST's flagship probe—weak gravitational lensing—and fully harnessing the potential of next-generation sky surveys through multi-probe analysis.

The scientific project focuses on testing dark energy and gravity, primarily through weak lensing correlation studies with LSST and, potentially, their complementarity with other probes (galaxy clustering, supernovae, etc.).

Candidates are expected to propose a research project, with a portion dedicated to weak lensing data analysis with LSST. This could include sensor characterization using dedicated bench or in-situ data, the development and validation of a shear estimator, and final cosmological inference.

Cross-disciplinary analyses, in connection with the group's multi-probe combination projects, are strongly encouraged. Additionally, collaborations with research laboratories in the Paris region to further develop this research axis are possible.

Candidates will be invited to propose a teaching project related to the LSSTLens junior professorship. This project will include either 28 hours of lectures or 42 hours of practical or tutorial sessions. Once selected, the recruited candidate will collaborate with Sorbonne University, the LPNHE's academic institution, to discuss and finalize the teaching program.

The CNRS is developing a strong policy in favor of open science. Open science consists of making research results "as accessible as possible and closed as necessary". As such, the CNRS aims to make 100% of the texts of publications resulting from the work of its laboratories accessible , in particular through deposit in HAL. The data produced must also be made available and reusable, except for specific restrictions. In addition, the guiding principles of individual evaluation have been revised in accordance with the DORA declaration, to be more qualitative and to take into account all facets of the researcher's profession.

The dissemination of the results will be done through world-class scientific productions: publications, patents, software... In addition, the results will be communicated to various targets such as scientific communities, media, decision makers, general public, schools, etc., with an adapted calendar. Specific tools may be developed such as websites, newsletters, meetings, international symposia, summer schools and conferences.

The relationship between science and society is now recognized as a full dimension of scientific activity. The project will develop this dimension in synergy with all the partners. The resulting research work will contribute to informing public decision-making. Participatory science initiatives may be initiated with actors from the project's socio-economic and cultural eco-system.

holders of a doctorate or a PhD or equivalent degree or applicants who have gained scientific. There is no restriction on the age or nationality of applicants. All CNRS positions are accessible to people with disabilities, with special arrangements for tests made necessary by the nature of the disability.