Missions

The H.E.S.S./CTAO team at LPNHE is involved in analyzing data from the H.E.S.S. experiment, particularly in the study of high-energy emissions from extragalactic sources, such as active galactic nuclei (AGN) and gamma-ray bursts (GRB). The team is also involved in the construction of CTAO, the future very high energy observatory, with the development of fast acquisition electronic boards (FEBs) that equip NectarCAM, one of the two concepts for CTAO's Medium-Sized Telescopes (MSTs).

The successful candidate will focus on developing an innovative approach to measuring the Hubble constant (H₀) using gamma-ray observations. The project aims to address the current tension in H₀ measurements using data from major gamma-ray instruments, such as Fermi-LAT, the Cherenkov telescopes H.E.S.S., MAGIC and VERITAS as well as the future CTAO observatory.

Activities

The successful candidate will develop open-source software that integrates with the Gammapy framework, enabling the integration of public data from current Cherenkov telescopes and the future CTAO. The successful candidate will ensure that the software can calculate H₀ and its uncertainties from AGN and GRB gamma-ray observations, with a focus on reproducibility and long-term maintainability. Existing data from H.E.S.S. and other instruments will be used to develop and validate the software pipeline. The successful candidate will also collaborate with the wider scientific community to promote the software, gather feedback, and integrate additional features based on user needs. The successful candidate will also have the opportunity to be involved in activities related to the preparation and commissioning of the NectarCAM cameras if they wish.

Skills

The candidate must hold a PhD (or equivalent) in high-energy astrophysics, obtained no earlier than December 1, 2023. Prior experience in gamma-ray astronomy is desirable, but not required. Strong Python programming experience would be an asset. The starting date is December 1, 2025, but a later date may be considered.

Applications should include a CV with a summary of previous research activities and a statement of interest.

Work Context

The LPNHE (Laboratoire de Physique Nucléaire et des Hautes Energies, https://lpnhe.in2p3.fr/) is a laboratory of the IN2P3 (Institut National de Physique Nucléaire et de Physique de Particules), a CNRS institute, and of the universities « Sorbonne Université » and « Université de Paris ». The laboratory is located in Paris, France. It is involved in major international collaborations in particle physics, astroparticle physics, and cosmology. Approximately 130 permanent staff members work at the LPNHE.

The LPNHE's H.E.S.S./CTAO team is currently involved in simulations and H.E.S.S. data analysis, as well as in the preparation of the future CTA observatory. The team is composed of three permanent researchers, a postdoctoral fellow, and a doctoral student.

LPNHE is also part of the Paris region (GRIF) node of the European Grid Infrastructure (EGI), hosting medium-sized computing and data storage facilities, but contributing significantly to the processing of simulations for H.E.S.S. and CTAO, for example. In addition, membership in the H.E.S.S. collaboration will allow the successful candidate to access the CC-IN2P3 national computing center.