31 research outputs found
Sensitivity of the SHiP experiment to Heavy Neutral Leptons
Heavy Neutral Leptons (HNLs) are hypothetical particles predicted by many
extensions of the Standard Model. These particles can, among other things,
explain the origin of neutrino masses, generate the observed matter-antimatter
asymmetry in the Universe and provide a dark matter candidate.
The SHiP experiment will be able to search for HNLs produced in decays of
heavy mesons and travelling distances ranging between and tens of kilometers before decaying. We present the sensitivity of the
SHiP experiment to a number of HNL's benchmark models and provide a way to
calculate the SHiP's sensitivity to HNLs for arbitrary patterns of flavour
mixings. The corresponding tools and data files are also made publicly
available.Comment: journal versio
The active muon shield in the SHiP experiment
The SHiP experiment is designed to search for very weakly interacting particles beyond the Standard Model which are produced in a 400 GeV/c proton beam dump at the CERN SPS. An essential task for the experiment is to keep the Standard Model background level to less than 0.1 event after protons on target. In the beam dump, around muons will be produced per second. The muon rate in the spectrometer has to be reduced by at least four orders of magnitude to avoid muon-induced combinatorial background. A novel active muon shield is used to magnetically deflect the muons out of the acceptance of the spectrometer. This paper describes the basic principle of such a shield, its optimization and its performance.Peer Reviewe
A facility to Search for Hidden Particles (SHiP) at the CERN SPS
A new general purpose fixed target facility is proposed at the CERN SPS
accelerator which is aimed at exploring the domain of hidden particles and make
measurements with tau neutrinos. Hidden particles are predicted by a large
number of models beyond the Standard Model. The high intensity of the SPS
400~GeV beam allows probing a wide variety of models containing light
long-lived exotic particles with masses below (10)~GeV/c,
including very weakly interacting low-energy SUSY states. The experimental
programme of the proposed facility is capable of being extended in the future,
e.g. to include direct searches for Dark Matter and Lepton Flavour Violation.Comment: Technical Proposa
Addendum to Technical Proposal: A Facility to Search for Hidden Particles (SHiP) at the CERN SPS
With the Technical Proposal submitted to the SPSC committee in April 2015, the SHiP collaboration declared its interest in proceeding towards a Comprehensive Design Study phase with the aim of preparing for the Technical Design Reports pending an approval by the CERN committees. Following the recommendation by the SPSC, it has been decided to complement the TP with this addendum that provides an update of the key aspects for the review of the SHiP project
Measurement of the muon flux from 400 GeV/c protons interacting in a thick molybdenum/tungsten target
The SHiP experiment will search for very weakly interacting particles beyond the Standard Model which are produced in a 400 \GeV/ proton beam dump at the CERN SPS. About muons per spill will be produced in the dump. To design the experiment such that the muon-induced background is minimized, a precise knowledge of the muon spectrum is required. To validate the muon flux generated by our Pythia and GEANT4 based Monte Carlo simulation (FairShip), we have measured the muon flux emanating from a SHiP-like target at the SPS. This target, consisting of 13 interaction lengths of slabs of molybdenum and tungsten, followed by a 2.4 m iron hadron absorber was placed in the H4 400~\GeV/ proton beam line. To identify muons and to measure the momentum spectrum, a spectrometer instrumented with drift tubes and a muon tagger were used. During a three-week period a dataset for analysis corresponding to protons on target was recorded. This amounts to approximatively 1\% of a SHiP spill
Sensitivity of the SHiP experiment to dark photons decaying to a pair of charged particles
Dark photons are hypothetical massive vector particles that could mix with ordinary photons. The simplest theoretical model is fully characterised by only two parameters: the mass of the dark photon mγD and its mixing parameter with the photon, ε. The sensitivity of the SHiP detector is reviewed for dark photons in the mass range between 0.002 and 10 GeV. Different production mechanisms are simulated, with the dark photons decaying to pairs of visible fermions, including both leptons and quarks. Exclusion contours are presented and compared with those of past experiments. The SHiP detector is expected to have a unique sensitivity for mγD ranging between 0.8 and 3.3+0.2−0.5 GeV, and ε2 ranging between 10−11 and 10−17