Short description

The PhD position is proposed for a 3-year period (36 months). The legal net salary is €1768 per month (plus social benefits). An annual €2 000 package for travels and equipment will be allotted. The candidate is expected to submit a thesis manuscript to the university of Lyon for a formal presentation in front of a jury before the end of the 3-yr period.

Starting date of the contract: October the 1st, 2021

Research project (1/2 page – 1 page)

Muography is an innovative investigation method using cosmic-rays induced atmospheric muons to probe large structures of geological relevance. In the last decades the method has known a fast and important development and has been applied in various fields from geosciences (volcanology, hydro-geology, atmosphere physics etc) to industrial controls and monitoring (civil engineering, tunnel boring machines, nuclear plants etc).

The basic principles of the method are similar to those of medical X-ray imaging where the absorption of the incident particles flux is interpreted in terms of opacity of the target. The main difference relies in the fact that the particles used for the measurement are naturally produced in the atmosphere with a given and limited statistics. This induces severe constrains on the way the inverse problem is thought and applied.

The main objective of the project is to improve present methods to increase the sensitivity of muography in terms of spatial imaging capability and of timing resolution for all monitoring applications (follow-up of the content of a target with time and assessment of the typical time constants). One possible improvement arises from possible coupling of muography measurements with other geophysical measurements like seismic noise recording, electrical resistivity tomography, gravimetry etc. A possible development may be based on recent developments using optical fibers as distributed acoustic or strain sensors monitoring large areas as well as means of implementation of precise timing and synchronization. A coupling between muography and distributed fibers would be a very promising multi-messenger approach.

The results obtained may be constrained on different near surface targets : structural imaging of a shallow archaeological site south Lyon, analysis of the hydrothermal system dynamics,

investigation of effect of newtonian noise sources on the sensitivity of gravitational antennas like Virgo close to Pisa. The subject has a lot of potential applications in the industry for the long-term storage problematics or the urban civil engineering for instance.

1. Monitoring temporal opacity fluctuations of large structures with muon tomography : a calibration experiment using a water tower tank Jourde, K., Gibert, D., Marteau, J., de Bremond d'Ars, J., Gardien, S., Girerd, C., Ianigro, J.-C., Nature Publishing Group, 2016, 6, pp.23054. arXiv : 1504.02230
2. Muon dynamic radiography of density changes induced by hydrothermal activity at the La Soufrière of Guadeloupe volcano, Jourde, K ., Gibert, D., Marteau, J., de Bremond d'Ars, J., Komorowski, J.-C., Scientific Reports, #SREP-16-22509A, arXiv:160603003.
3. 3-D structure of the La Soufrière de Guadeloupe shallow hydrothermal system from muon tomography, gravity and electrical resistivity data, Rosas-Carbajal, M., Jourde, K., Marteau, J., Deroussi, S., Komorowski, J.-C., Gibert D., Geophysical Research Letters, DOI: 10.1002/2017GL074285, arXiv 1707.02604.
4. Abrupt changes of hydrothermal activity in a lava dome detected by combined seismic and muon monitoring, Le Gonidec, Y., M. Rosas-Carbajal, J. de Bremond d’Ars, B. Carlus, J.-C. Ianigro, B. Kergosien, J.Marteau, and D. Gibert, 2019, Scientific Reports (2019) 9:3079, https://doi.org/10.1038/s41598-019-39606-3, arXiv:1811.07183
5. Middle-atmosphere dynamics observed with a portable muon detector, Tramontini, M., Rosas-Carbajal, M., Nussbaum, C., Gibert, D., Marteau, J., Earth and Space Science 2019, doi: 10.129/2019EA000655.

Research field(s)

The candidate should have a significant knowledge in the following domains: Physics of complex systems, heat and mass transfers, numerical modelling, non-linear signal processing, multiscale analysis, data inversion, and dynamic tomography.

Thesis supervisor and contact

Name : Dr. Jacques MARTEAU,

IP2I (UMR 5822), CNRS/IN2P3, Lyon 1 University, F-69622 Villeurbanne, France. Phone number: +33 4 72 43 15 81.

Email: j.marteau@ip2i.in2p3.fr

WORKING ENVIRONMENT

Job location and description

The host laboratory will be the IP2I laboratory Particle Physics located on the La Doua Campus of Lyon 1 University in Villeurbanne with strong interactions with the LGL Geosciences laboratory located on the same campus. The candidate will also work with the others teams involved in the projects of the muography group of IP2I (ANR MeGaMu research program, 2020-2025, Mont-Terri Underground Laboratory Phase 26 – 28, 2021- 2023, MITI research program, 2021-2023). The candidate will interact with colleagues from LGL (seismologists, data scientists), IP2I (particle physicists), IPGP (geophysicists).

Team

Presently, no PhD student is under the supervision of Jacques Marteau, IP2I.

Allocated resources

The project heavily relies on massive numerical time-space modelling using the computing facilities of the CCF/Cluster of the LIO labex. It will also use detectors already existing in IP2I and LGL.

Description of LabEx LIO

In 2011, The Lyon Institute of Origins LabEx was selected following the first “Laboratory of Excellence” call for projects, part of the “Investissement d’Avenir” program for forward- looking research. It is one of 12 LabExes supported by the University of Lyon community of universities and establishments (COMUE). LIO brings together more than 200 elite researchers recruited throughout the word and forming 18 research teams from four laboratories in the Rhône-Alps region, all leaders in their fields, under the auspices of the University Claude Bernard Lyon 1 (UCBL), the Ecole Normale Supérieure de Lyon, and the CNRS. LIO’s goal is to explore questions about our origins, operating in a broad field of study that ranges from particle physics to geophysics, and includes cosmology, astrophysics, planetology and life

SELECTION PROCESS

The successful candidate will be selected in partnership with the Doctoral School « Physics and Astrophysics » of the University of Lyon.

Condition for admission to doctoral studies

The candidates must hold a national master degree or equivalent.

Application deadline

May the 1st, 2021

Requested documents for application

The candidates must submit their application with (i) their academic curriculum of the last three years, (ii) a letter of motivation, (iii) a CV and (iv) a letter of recommendation, to labex.lio@universite-lyon.fr before May the 1st, 2021.

Candidates on the short list will be informed by the end of May. They will be interviewed in June.