français | anglais
LPHE - Research
Informations générales
Recherche (english only)
TELL1 Home Page
Postes à pourvoir



The Research at LPHE

The Laboratory for High Energy Physics (LPHE) at the Swiss Federal Institute of Technology of Lausanne is involved in several international collaborations for research in particle physics, with present and future experiments. This research requires ongoing technical developments in particle detection, signal processing electronics, and computing.

LPHE's research programme in high energy physics is concentrated on the study of CP violation and other rare phenomena in B decays with the LHCb detector at CERN. LPHE also participates in the analysis of the data taken with the BELLE detector, at KEK's asymmetric e+e- B factory in Japan.

In the domain of astroparticle, with prof. M. Ribordy, LPHE joined the IceCube experiment, a neutrino detector at the South Pole. We also participate in the R&D effort for the construction of a spectrometer for the search for dark matter signals in cosmics (PEBS experiment).

The Laboratory has been a member of the L3, NOMAD, UA6, and WA42/62 collaborations at CERN, and of the HYPERCP experiment at Fermilab (USA). We also carried out several experiments at the Paul Scherrer Institute.

Until 2007, the Laboratory had a R&D programme for the applications of particle physics and its experimental techniques to imaging (for medical or bio-research purpose), using Position Emission Tomography (PET).

LPHE's funding agencies are the Swiss Federal Institute of Technology, the Swiss National Science Foundation and FORCE (a federal fund for research at CERN). Until the end of 2003, the Laboratory was also financed by the University of Lausanne and the Canton de Vaud.

A brief summary of present activities: LHCb | BELLE | ICECUBE, and of past activities: PET | NOMAD | L3 | E871 | UA6 | Photim.

Finally, the Institute offers accademic support for CERN Ph.D. students, involved in various R&D projects in accelerator technology and instrumentation.

LHCb is an experiment whose purpose is to study CP violation in the B mesons system at the future LHC collider.


BELLE is an experiment at the KEK B-factory. Its goal is to study the origin of CP violation.


The IceCubeNeutrino Detector is a neutrino telescope currently under construction at the South Pole. The main goal of the experiment is to detect neutrinos in the high energy range, which spans from 1011 to about 1021 eV.

IceCube at LPHE

Attached to a balloon at an altitude of ~40 km, the PEBS detector will measure the positron and electron spectra in cosmic rays up to an energy of 600 GeV and 2 TeV respectively, thus providing crucial data to confront with dark matter theories.


PET (Positron Emission Tomography) is a medical imaging technique that allows to investigate the biochemical activity in living organisms using radioactive tracers.


NOMAD is an experiment whose purpose is to look for evidence of neutrino oscillations. These oscillations are suggested by the difference between expected and detected solar neutrino fluxes on earth. The experiment is located in the CERN West Hall. It is composed of drift chambers, a transition radiation detector and an electrophotonic calorimeter installed inside a magnet providing a field of 0.4 T and muon detectors located outside the magnet. Kinematic criteria will be used to recognize oscillations from mu neutrinos to tau neutrinos.


L3 is an experiment designed to study electroweak interactions induced in electron-positron collisions at a center-of-mass energy of about 100 GeV (200 GeV to be achieved in the future) in the Large Electron-Positron collider (LEP) at CERN.

L3 at LPHE

E871 is a Fermilab experiment to study CP-violation in hyperon decays.

E871 at LPHE

_____ UA6 _____

UA6 is an internal fixed target experiment which was installed in the CERN-SPS collider ring. It used as target a hydrogen cluster jet and, thanks to the high density of the jet and the revolution frequency of the stored p and pbar beams, a luminosity of the order of 10^31 cm^-2 s^-1 has been achieved. The experiment was instrumented with a two-arm magnetic spectrometer equipped with multiwire proportional chambers and with electromagnetic calorimeters. Electron identification could be enhanced by transition radiation detectors.

First data was taken in 1984. Last period of data taking was in 1990 until the phase out of the SpS collider ring.

UA6 studies, among other things:
  • high pT direct photons production. These photons are directly emitted by the interacting quarks of the protons and antiprotons. They can be used to have a look on gluon contents of the proton and to measure the strong coupling constant.
  • pi0 production. Pi0 builds a strong background to direct photons measurements.
  • J/psi production. J/psi is a baryon (as the neutron and the proton). The mechanism that leads to its creation is not well known; but the study of J/psi production sheds some light on it.

Photim was a European 'ESPRIT' project in opto-electronic chain development. The scientific goal was the construction of a Cherenkov telescope for cosmic gamma rays detection.

Photim at LPHE