Profil Recherché

Titulaire d’un doctorat ou diplôme équivalent ou justifiant de titres et travaux scientifiques jugés équivalents par l’instance compétente de l’établissement. Il n’y a aucune condition d’âge ou de nationalité pour candidater. Tous les emplois CNRS sont accessibles aux personnes en situation de handicap en bénéficiant d’aménagement d’épreuves rendus nécessaires par la nature du handicap

Stratégie d'établissement

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.

Stratégie du laboratoire d'accueil

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.

Stratégie Internationale

Gravitational shear analyses are at the core of a worldwide scientific effort. They serve as a key test of the standard cosmological model (ΛCDM) and represent the primary probe for LSST, as well as for space missions like Euclid (launched in 2023) and Roman (scheduled for 2027). Several precursor projects, such as the Dark Energy Survey, the Subaru Strategic Program, and Unions, are currently underway.

The LPNHE holds a strategic position not only within LSST but also in complementary initiatives, including the DESI project. The selected candidate will have access to both collaborations and will also benefit from the rich research environment in cosmology at Sorbonne University, through the teams at LPNHE, IAP, and the upcoming Institute of the Cosmos.

Répertoire national des structures de recherche (RNSR) du laboratoire d'accueil

Laboratoire de physique nucléaire et des hautes énergies (LPNHE) - UMR7585199712631X

Résumé du projet scientifique

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.

Résumé du projet d'enseignement

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.

Environnement Financier

• Total financé (dont package ANR) : 200 k€
• Total du projet : k€

Diffusion scientifique

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.

Science ouverte

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.

Science et société

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.

Indicateurs

The activity will be evaluated in particular on the basis of scientific production (publications, software, patents, etc.), on institutional and private partnerships formalized by contracts, on international presence, on the promotion of work to multidisciplinary scientific communities, on innovation and its transfer to society and on scientific dissemination to non-specialist audiences.

Modalités d'organisation des auditions

Seul(e)s seront convoqué(e)s aux auditions les candidat(e)s sélectionné(e)s sur dossier par la commission de sélection