DPhP
The core of DPHP’s activities is to understand the energy content and dynamics of the Universe at a fundamental level, deploying the appropriate experimental resources, in synergy with other IRFU departments and in line with international scientific strategy. In particle physics, the established theoretical foundation is the Standard Model of particle physics, which has proven to be extremely robust, predictive, and comprehensive since the discovery of the Higgs boson in 2012. The last decade has seen a paradigm shift in terms of scientific strategy. Teams are no longer seeking to establish the Standard Model, but to go beyond it.
The department is pursuing this strategy from three angles :
• Testing the internal consistency of the Standard Model through precision measurements at the LHC, then in the future at the HL-LHC, and finally in the longer term at a future collider yet to come.
• Testing the fundamental symmetries of the Standard Model by studying neutrinos or antimatter.
• Studying the dark, extreme, and gravitational universe by probing the universe with the various messengers at our disposal: studying dark energy, dark matter, gravitational waves, cosmic neutrinos, or hypothetical axions.
Some of the fundamental questions addressed by the DPHP through these areas of research :
• Can the Standard Model be challenged by precise measurements in the electroweak, Higgs, and top quark sectors? Could the Higgs boson be the key to revealing new physics beyond the Standard Model? Is the Higgs boson standard? What is the mass of the top quark?
• What is the fundamental nature of dark matter? Can dark matter be produced in colliders? Can the dark matter that makes up the galactic halo be detected, either directly in low-background experiments or indirectly through high-energy cosmic messengers?
• What is the equation of state of dark energy? Is dark energy simply a cosmological constant, or does it evolve with universal time?
• Is the neutrino a Majorana or Dirac particle? Are there more than three flavors of neutrinos? Is CP symmetry violated in the lepton sector? What is the mass scale or mass order of neutrinos? What is the role of neutrinos in cosmic evolution and structure formation? Are internal symmetries fundamental?
• Does gravity act in the same way on matter and antimatter? What is the nature of gravity? Does general relativity provide an accurate description of it? Is there a unification of the four interactions? What is the nature of the phase transitions corresponding to symmetry breaking in the early Universe?
• What is the origin of the most energetic cosmic phenomena, such as gamma-ray bursts and very high-energy cosmic rays?
The DPHP’s strategy is to maintain a balance between the different experimental and observational approaches to these fundamental questions, or other questions that may arise.
Access to DPhP's website : http://irfu.cea.fr/dphp/en/index.php
Head of the Particle Physics Division: Nathalie Besson
Deputy-head: Georges Vasseur
Secretary : Sarra Bounab