Description du sujet de thèse

Contributions to Gravitational Wave Astronomy; Toward a better identification of more events.
Objectives of the thesis:
The GW astronomy is a new field started a few years ago with the first observation of GW in 2015. It has been followed two years later by the first observation of GW plus electromagnetic signals (GRB, optical, radio). Since then, this field is rapidly evolving, thanks to the improvement of the detectors and new data taking, with about 300 events observed as of May 2025. Currently, the LIGO and Virgo detector are jointly operated as part of the fourth observing run (O4), detecting GW events at a typical rate of few events per week. The O4 run will stop in November to allow for detector upgrades before restarting observations in late 2027 with improved detection capability.

The Virgo OGMA group is involved in the search for GW events from the coalescence and merger of binary systems of compact objects (black holes and/or neutron stars). It is focusing its data analysis effort on the development and deployment of the MBTA analysis pipeline. This includes real-time analyses to provide candidate events which are publicly broadcasted and the production of signal catalogues.

The proposed PhD work is to contribute to the analysis of the O4 data, improve the analysis for the O5 run and look at the first O5 results. The O5 detection rate is expected to increase by at least a factor 3 compared to O4, leading to new opportunities for discovery and challenges for the data analysis.

The PhD work will have two main phases. First, a contribution to the offline analysis of the data collected during the O4 run in order to include the results in the catalogues. The second phase is to prepare the pipeline improvements for the O5 run, and contribute to the analysis of the first data of this run. The emphasis will be to improve the source classification, parameter estimation in low latency, key parameters for the selection of the appropriate events for MultiMessenger followup. The inclusion of the data coming from the Japanese KAGRA detector will be another topic.

Contexte de travail

The PhD will be attached to the Doctoral School of Physics and Chemical-Physics of the University of Strasbourg (ED182).
The candidate will be based at the "Institut Pluridisciplinaire Hubert Curien" (IPHC) in Strasbourg (Subatomic Research Department).
The Institut Pluridisciplinaire Hubert CURIEN (IPHC), a joint research unit under the joint supervision of CNRS and the University of Strasbourg (UMR7178), is a multidisciplinary laboratory where research teams from different scientific cultures (ecology, physiology and ethology, chemistry and subatomic physics) develop very high level programs based on scientific instrumentation. The IPHC is structured into 4 departments and has a total staff of 393 staff including 257 permanent staff (ie 119 researchers and teachers / researchers and 138 engineers and technicians), 46 staff on fixed-term contracts and 102 doctoral students.
The PhD student will become a member of the Virgo collaboration, in charge of the Virgo gravitational wave detector located close to Pisa in Italy. Since LIGO, Virgo and KAGRA share their data and have common data analysis teams and publications, the PhD student will be fully integrated in this joint effort.
The candidate must hold a master's degree. He or she will need to prove a solid knowledge of general physics, astroparticules and data analysis.
The candidate will have to master English in writing and orally English at level B2 according to the Common European Framework of Reference for Languages in order to be able to contribute to the activities of the Virgo and LIGO collaborations.
The international, multidisciplinary and collaborative context of this project requires that the candidate has a strong motivation, curiosity to expand his area of expertise, autonomy and ability to work in a team with strong constraints to meet deadlines.
Applications should include a detailed CV, a letter of motivation, a summary of the Master's thesis as well as the grades of Master 1 and 2.

The candidate will benefit from access to an administrative restaurant, partial reimbursement of travel expenses, a works council, the possibility of teleworking and training to adapt to the job.