Neutrinos@LHC
"The prototype of a neutrino detector developed for the SHiP experiment is set to be installed at the LHC before the next run. The letter of intent, subscribed by LIP, has been recently submitted to CERN."
During the introductory lectures of the ongoing edition of the LIP Internship Program, students will have been told that neutrinos are not detected at the LHC (their presence being inferred only via missing energy). What if they were? That’s exactly what the newly proposed LHC detector aims to achieve. For this, we need a detector with very specific characteristics, in particular containing a target with an emulsion in which neutrinos can interact and be detected.
SHiP is a new experiment designed to complement the LHC experiments in the search for new physics (NP). It will use the high-intensity 0.4 TeV proton beam from the SPS accelerator. It is designed to study feebly interacting NP particles and neutrinos. While the experiment shall be installed at a new, yet-to-be-built beam-dump facility at CERN, the prototype of one of its components, the Scattering and Neutrino Detector, SND for short, is now proposed to start data taking sooner and at an order of magnitude higher energy. More precisely, at the upcoming Run 3 of the LHC.
Neutrinos are produced abundantly at colliders, still collider neutrinos have yet to be detected. The LHC will deliver the highest energies yet of man-made neutrinos, and their detection will be a milestone. SND will explore all three neutrino flavours (accessing a sizeable contribution from the tau flavour) in the unexplored energy domain (from 350 GeV to several TeV). The new detector will be installed in the LHC tunnel, away from the collision point and near the beam-line direction. Given its “off-axis” location, the detected neutrinos will originate primarily from heavy flavour decays (esp. charm). This further amounts to first tests of heavy flavour production in the forward region, not accessible to current LHC detectors. The search for feebly interacting particles (FIPs) is another major goal. FIP searches are currently drawing an explosion of interest as potential NP signals. The detector is expected to facilitate sensitivity to dark matter particles in the less explored GeV range.
The newly proposed LHC experiment is expected to provide the first measurements of collider neutrinos and to extend the exploration of the NP landscape beyond what is accessible by existing LHC experiments. LIP is involved in SHiP, and both in LHC and neutrino experiments, and this new endeavour has the potential to draw on multiple synergies.
Figure: Planned integration of the SND detector in the TI18 tunnel of the LHC.