Universite Clermont Auvergne

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A theoretical approach to particle physics, nuclear physics and cosmology cannot be separated from the corresponding experimental approach ; whilst in certain domains one may precede the other, a symbiosis between theory and experiment is crucial for the progress of both. While allowing for an active synergy with the experimental collaborations of the LPC, the research activities of the Theory Pole at the LPC encompass numerous topics of Particle Physics and Interdisciplinary Physics, within the framework of the IN2P3 research programme, being based on numerous national and international collaborations and networks.


Created in 1995, the Theory Pole is composed of five permanent members, both CNRS researchers and professors at the UCA, one postdoctoral researcher and a Ph.D. student.

The scientific research topics of the team have evolved from hadronic physics (QCD and relativistic few body systems) and pluridisciplinary physics (percolation models applied to biomaterials), to being currently focused on particle physics : Field Theory, Standard Model and New Physics, as well as Astroparticle Physics. Our research aims at addressing several open questions :

  • How are strongly interacting particles (quarks and gluons) confined in mesons and baryons ?
  • What is the origin of electroweak symmetry breaking ?
  • What is the nature of neutrinos ? Which is the mechanism responsible for their mass ?
  • Why is the Universe dominated by matter ? What was the mechanism responsible for baryogenesis ?
  • What is the nature of dark matter ?

Many of these are being (direct or indirectly) addressed by the experimental collaborations in the "Particles and Universe" pole. The members of the group have important interactions with other LPC groups, especially ATLAS, LHCb, COMET and CKMFitter.

The Theory pole members contribute to the local scientific animation, and belong to the organising committees of a large number of national and international meetings (Schools, Workshops, Conferences), being also engaged in several Outreach activities ; they further hold numerous scientific and academic responsibilities (in national and international committees and boards). They are also active members of several French research federations, including the IRN Terascale, IRN Neutrinos, GdR Intensity Frontier and GdR DUPhy.

Job opening : postdoc fellowship


The activities of the Theory Pole are currently focused on Particle Physics. The members pursue formal research in Field Theory, develop theoretical tools potentially applicable to particle physics, and carry extensive phenomenological studies in direct connection with experiment, focusing on flavour physics (quarks and leptons), neutrino physics and Dark Matter.
Our research revolves around the following axes :

  • Field Theory : field theory on the light front and finite field theories (based for instance on the Taylor-Lagrange renormalisation scheme). Application to physical observables in 3+1 dimensions and perturbative computation of radiative corrections to the Higgs boson mass.

  • Standard Model of Strong and Electroweak interactions

    • Lattice QCD Semi-leptonic decays of B-mesons into the first orbital excitations of D-mesons
    • Heavy flavour phenomenology (study of b-hadron decays using covariant formulation of quark models à la Bakamjian-Thomas ; lepton flavour universality violation in heavy beauty-baryon semileptonic decays)
    • Precision tests (in the framework of the CKMFitter Collaboration)
  • Beyond the Standard Model : New Physics
    • Indirect searches from flavour physics : lepton flavour violation (low-energy and collider prospects), lepton number violation, heavy flavour physics (semi-leptonic B-decays, lepton universality tests, ...), flavoured tensions & anomalies
    • Neutrino phenomenology : sterile fermion searches, lepton properties, models of neutrino mass generation
    • Direct searches at the LHC and prospects for future colliders (extended gauge and scalar sectors, exotic fermions, long-lived particles, ...)
  • Dark Matter
    • New physics candidates : relic density, prospects for direct and indirect detection
    • "Freeze-in" dark matter and baryogenesis : theory & phenomenology of "freeze-in" mechanism of DM production (early Universe) ; relation to theory and phenomenology of long-lived particles (observation and reconstruction of properties at HL-LHC) ; potential connections between baryogenesis and freeze-in mechanism of DM production
  • Application to health sciences
    • Modelisation of the transformation of biomaterial implants in bones within percolation theory
    • Highlighting the impact of social relationships on the propagation of respiratory viruses using percolation theory - development of "PERCOVID"




  • Jonathan Kriewald (UCA Postdoc)
  • Emanuelle Pinsard (UCA Ph.D. student)
  • Andreas Goudelis (CNRS researcher)
  • Jean-François Mathiot (CNRS research director)
  • Vincent Morénas (Professor, UCA)
  • Jean Orloff (Professor, UCA)
  • Ana M. Teixeira (CNRS research director, head of Theory group)


  • Mariam Atoui (Ph.D. student UBP, 2010-2013)
  • Gabriela Bailas (Ph.D. student, IN2P3, 2015-2018)
  • Valentina De Romeri (Postdoctoral fellow, EU ITN "Invisibles" Network, 2013-2015)
  • Antoine Gérardin (Postdoctoral fellow IN2P3, 2014-2015)
  • Chandan Hati (CNRS-IN2P3 postdoctoral fellow, 2017-2019)
  • Jonathan Kriewald (UCA PhD student)
  • Farvah Nazila Mahmoudi (MdC-UBP, 2008-2014)
  • Hubert Mély (Ph.D. student, 2008-2011)
  • Bruno Mutet (Postdoctoral fellow, 2010-2011)
  • Siavash Neshatpour (Ph.D. student, 2009-2013)
  • Natalia Tsirova (Postdoctoral fellow, 2008-2010)
  • Savvas Zafeiropoulos (Postdoctoral fellow IN2P3, 2013-2014)


Andreas Goudelis :
  • Responsible for the internal communication at LPC
  • Co-organiser of the LPC weekly seminars
  • Responsible for the Theoretical Physics session at the Journées Jeunes Chercheurs (2019, 2022)
Jean-François Mathiot :
  • Member of the 29th section of the CNU (Conseil National des Universités)
  • President of Committee for Scientific Prospectives of the LPC (2018)
Vincent Morénas :
  • President of the local French Physical Society section (SFP-Auvergne)
  • PI of the "Lattice calculations in Hadronic Physics" IN2P3 project (2016-2020)
Jean Orloff :
  • President of the UCA Physics Department
  • Member (elected) of Council of the UCA Physics and Engineering School
  • President of the Scientific Council of the LPC
Ana Teixeira :
  • Member of the LPC Council
  • Member of the COMET collaboration
  • Member of the group responsible for the "Flavour physics" chapter of the "Update of the European Strategy for Particle Physics (ESPP) 2019"
  • Chargée de Mission IN2P3 "Theory and Phenomenology" (since 2022)
  • PI of the "Flavour Probes" IN2P3 project (2020-2023) and "Lepton Flavours" IN2P3 project (2016-2019)
  • PI of the FJPPL project "LFV : muon to electron, and the tau sector" (2021-2023)


The members of the Theory Pole are involved in numerous national and international research networks and federations

European Union HIDDeN ITN
A. M. Teixeira, J. Orloff: members of the French node
iTHEPHY Erasmus+ iTHEPHY Strategic Partnership
for Innovating Team-Teaching for Physics
J. Orloff: French coordinator
"European Twisted Mass Collaboration"
V. Morénas: member of the collaboration
CKMFitter” Project
J. Orloff: member of the collaboration
"The International Light Cone Advisory Committee" - ILCAC
J.-F. Mathiot: member of ILCAC
IRN “Terascale”
A. M. Teixeira: co-director of the IRN Terascale
J. Orloff: steering council of the GdR “Terascale”
IRN “Neutrino”
A. M. Teixeira: coordinator of the “Beyond the SM” group
GdR "Intensity Frontier"
A. M. Teixeira: coordinator of the "Interplay of Quark and Lepton Flavours" group


The Theory Pole hosts, and/or is directly involved in the organisation of numerous national and international events : Workshops, Schools, Meetings...

  • "Célébration des 50 ans de l’IN2P3 au LPC", LPC 18 June 2021 (J. Orloff, organising committee).
  • "Atelier Physique Theorique des 2 infinies’’, CNRS 2021 (A. M. Teixeira, organising committee).
  • "Breakfast with muon (g-2)’’, May 2021 (GdR High-Intensity Frontier, A. M. Teixeira, organising committee).
  • “IRN Terascale" Plenary meeting at Clermont-Ferrand, LPC, 22-24 November 2021 (A. Goudelis, J. Orloff, A. M. Teixeira, organising committee).
  • “Third International Conference on Charged Lepton Flavour Violation", Fukuoka, Japan 17-19 June 2019 (A. M. Teixeira, IOC).
  • “Rencontres de Physique des Particules – RPP2019”, LPC, 23-25 January 2019 (J.-F. Mathiot, J. Orloff, V. Morénas, A. M. Teixeira, organising committee).
  • "Rencontres de Moriond - Electroweak session”, La Thuile, Italy (J. Orloff, organising committee).
  • “Cargèse International Summer Schools in High Energy Physics", Cargèse, France (J. Orloff, organising committee, 2007, 2010, 2012, 2014, 2018, 2022).
  • “École d’été de physique e2ϕ”, Clermont-Ferrand, 25-28 August 2014 (Local organising committee : V. Morénas-president, J.-F. Mathiot).
  • “Invisibles Workshop 2014”, Institut des Cordeliers, Paris, 14-18 July 2014 (A. M. Teixeira, V. De Romeri, organising committee).
  • “Invisibles School 2014”, Château de Buton, Gif-sur-Yvette, 8-13 July 2014 (A. M. Teixeira, V. De Romeri, organising committee).
  • “GdR Neutrino" Plenary meeting at Clermont-Ferrand, LPC, 9-10 June 2015 (V. De Romeri, J. Orloff, A. M. Teixeira, organising committee).



  • Postdoctoral Fellowship at the LPC Clermont

    The Theory Group of the LPC opens a call for applications concerning a two-year postdoctoral position.
    The fellowship is funded by the CNRS IN2P3 (Institut National de Physique Nucléaire et de Physique des Particules), for a duration of two years, starting in the Fall 2023 (no later than 01/10/2023).
    The appointment is foreseen in the area of particle physics phenomenology ; applicants with an expertise on BSM phenomenology, flavour physics (leptons & quarks) and neutrino physics are invited to apply. At the starting date, applicants should already have their Ph.D. and preferably some postdoctoral experience (up to 3 years).

    Applications including a CV, a research statement and list of publications should be submitted exclusively via the dedicated CNRS application portal open from October 27th to December 8th, 2022.

    Applicants should also arrange for 3 recommendation letters to be submitted, before December 8th 2022, to the address indicating in the subject line "Postdoc TH 2022", as well as the name of the applicant.
    (We notice that will follow the "Theoretical High Energy Physics Groups Common Deadline for Postdoc Offers" agreement.)

    More information on CNRS job portal and on the job description file

    Contact and further information : indicating in the subject line "Postdoc TH 2022 - info"