Feebly Interacting Particles III: Searches at the LHC

by Albert De Roeck (Imperial College (GB))

Wednesday 14 Oct 2026, 14:00 → 16:00 Europe/Zurich

503/1-001 - Council Chamber (CERN)

Abstract:

Following the overview of the physics motivation for feebly interacting particles (FIPs), and
a survey of the search results and potential at the SPS this lecture will review the experimental
programme dedicated to their search at the Large Hadron Collider (LHC). The LHC
started operation fully in 2010 and the first searches for new physics were targeting mostly
possible new heavy particle production in the probed high energy regime. But with time increasing
attention was also payed to the search of FIPs, with potentially GeV-level masses.

The lecture will present the complementary experimental techniques employed at the LHC,
briefly addressing prompt production searches, conducted in standard analyses with the central
detectors. More emphasis will then be given to long-lived particle searches and the progress
that has been made to tailor analyses for searches of these channels. In particular, to
significantly extend the sensitivity for detecting long-lived particles a number of proposals
for possible new experiments and experimental facilities have been brought forward over the
last 5-10 years, which will enter the planned roadmap discussion, and these proposals will be
reported in this lecture

Since a few years also neutrino interactions studies and FIPs searches at the LHC have been conducted
deploying newly added detectors for the LHC Run-3, which have demonstrated the potential and
added value of such experiments.

Bio: 

Prof. Albert De Roeck was until 2025 a senior research scientist in experimental particle physics
for more than 25 years at CERN, and is presently connected to Imperial College London, UK,
and teaching at Antwerp University, Belgium, Chulalongkorn University Bangkok and
NTU, Singapore. He was  deputy spokesperson of the CMS experiment in 2010-2011 and Higgs
search/analysis group convener in CMS during 2012-2013. From 2016 onwards he in addition also
led the then newly established CERN EP neutrino group but kept a continuing special interest in analyses
and exploring experimental opportunities for searches for BSM physics, especially via long-lived particles
such as Heavy Neutral Leptons, at CMS and the LHC.
Presently he is also a member of the SHiP/SND@LHC and the MilliQan FIP-searching experiments.
He is also a co-organizer of the Long-Lived Particle community workshops.