The European Strategy for Particle Physics, updated in June 2020, will guide the direction of the field to the mid-2020s and beyond. To inform this vital process, the Secretariat of the European Strategy Group (ESG) called upon the particle-physics community across universities, laboratories and national institutes to submit written input by 18 December 2018.
Input was submitted via a portal on the Strategy Update website. Community proposals submitted are available here.
The update of the European Strategy got under way in September 2017 when the CERN Council established a Strategy Secretariat (CERN Courier November 2017 p37). Chaired by Halina Abramowicz, former chair of the European Committee for Future Accelerators (ECFA), the Secretariat includes Keith Ellis (chair of CERN’s Scientific Policy Committee), Jorgen D’Hondt (current ECFA chair) and Lenny Rivkin (chair of the European Laboratory Directors' Meeting).
The ESG Secretariat, which has been assigned the task of organising the update process, proposed to broadly follow the steps of the previous two strategy processes concluded in 2006 and 2013. An Open Symposium, in which the community was invited to debate scientific input into the strategy update took place in Granada (Spain) on 13-16 May 2019. The event attracted around 600 participants.
A “Briefing Book” based on the discussions was then prepared by the Physics Preparatory Group and submitted to the ESG for consideration during a five-day-long drafting session which took place in Bad Honnef (Germany) on 20-24 January 2020. A special ECFA-EPS session during the European Physical Society Conference on High Energy Physics (EPS-HEP) in Ghent, Belgium, created another important opportunity for the community to provide input for the ESG’s Drafting Session.
The European Strategy Update takes into account the worldwide particle physics landscape and developments in related fields, and was initiated to coordinate activities across a large, international and fast-moving community. The third update comes as the scale of particle physics facilities is leading to increased globalisation of the field and as its research direction evolves.
Understanding the properties of the Higgs boson (which was discovered at CERN just before the previous strategy update) remains a key focus of analysis at the LHC and future colliders, as are precision measurements of other Standard Model (SM) parameters and searches for new physics beyond the SM.
Neutrino physics is another key area of interest, with much experimental activity taking place since the last update. A “physics beyond colliders” programme has also been established by CERN to explore projects complementary to high-energy colliders and projects of national laboratories. The European Astroparticle and Nuclear-Physics communities, meanwhile, recently launched their own strategies (CERN Courier September 2017 p6; March 2018 p7), which also fed into the European Strategy update.
“After the discovery of the Higgs boson, the field is presented with a number of challenges and opportunities,” says Abramowicz. “Guided by the input from the community, the European Strategy determines which of these opportunities will be pursued.”