Feebly Interacting Particles II: Searches at the SPS (2/2)

by Paolo Crivelli (ETH Zurich (CH))

Monday 13 Jul 2026, 14:30 → 16:00 Europe/Zurich

500/1-001 - Main Auditorium (CERN)

Abstract:

Following the overview of the physics motivation for feebly interacting particles (FIPs), this lecture will review the experimental programme dedicated to their search at CERN's Super Proton Synchrotron (SPS). Over the past four decades, the SPS has played a pioneering role in the exploration of hidden sectors, evolving from early beam-dump experiments to today's state-of-the-art fixed-target facilities exploring physics beyond the Standard Model at the intensity frontier.

The lecture will present the complementary experimental techniques employed at the SPS, including missing-energy and missing-momentum searches for invisible particles, as well as searches for visible decays of long-lived particles. It will discuss how these approaches provide sensitivity to a broad range of theoretical scenarios while highlighting their complementarity and recent experimental progress.

Particular emphasis will be placed on the unique capabilities of the SPS, whose versatile beam infrastructure supports a diverse programme probing dark photons, light dark matter, axion-like particles, heavy neutral leptons, and other feebly interacting particles over a wide range of masses and couplings. The lecture will conclude with an outlook on future opportunities for FIP searches at the CERN SPS.

Bio: 

Paolo Crivelli is Professor of Experimental Particle Physics at ETH Zurich. His research focuses on precision tests of fundamental symmetries and the search for physics beyond the Standard Model using exotic atoms, antimatter systems, and high-intensity fixed-target experiments.

He is co-spokesperson of the NA64 experiment at CERN, which pioneered the missing-energy and missing-momentum techniques using the active beam-dump approach to search for feebly interacting particles and light dark matter at the SPS. His current research also includes the development of future intensity-frontier experiments and precision measurements probing new physics.