Professor Piroué and his group has been heavily involved in two major research activities at CERN, Geneva, Switzerland: (1) the L3 experiment at the Large Electron Positron (LEP) collider, which provides high luminosity e+e- collisions in the c.m. energy range 80-200 GeV, and (2) the CMS experiment at the Large Hadron Collider (LHC) which is scheduled to start operation in 2005.
The Princeton group doing research at CERN consists at present of Prof. D. Marlow and P. Piroué, Senior Research Physicist D. Stickland, Assistant Prof. C. Tully, Staff Physicist S. Wynhoff, Graduate Students J. Mans and W. Fisher, and Technical Staff both at Princeton and CERN.
In 2000 the LEP energy was increased to 209 GeV, well beyond its original design energy, in order to investigate tantalizing hints of a Higgs boson at a mass of 114-115 GeV. Unfortunately the additional data obtained in 2001 were not sufficiently conclusive to justify further running in 2002, and hence the CERN management decided to shut down LEP. The dismantling of the detectors took place at the beginning of 2001.
The L3 experiment was one of four LEP experiments. Its main goals were the search for new particles, such as the Higgs boson, and the undertaking of precision tests of the Standard Model at the Z0 resonance and above the W+W- production threshold. The Princeton group played a leading role in the experiment, both in the detector construction and data analysis. More than 250 papers have been published. A comprehensive summary of the most significant research accomplished can be found below.
CMS is one of the two general-purpose detectors being constructed at the LHC to study p-p collisions at 14 TeV c.m. energy. The main physics objectives are searches for the Higgs boson(s), supersymmetry, and of course new phenomena. The Princeton group is involved in three areas: (1) the development of the CMS software and computing environment for US-based physicists, (2) the level 1 trigger and (3) the high-precision crystal electromagnetic calorimeter.
- L3 Collab., M. Acciarri et al., "Measurement of Cross Sections and Forward-Backward Asymmetries at the Z Resonance and Determination of Electroweak Parameters", European Physical Journal C16, 1-40 (2000)
- L3 Collab., O. Adriani et al., "Determination of the Number of Light Neutrino Species", Phys. Lett. B 292 (1992) 463
- L3 Collab., P. Achard et al., "Standard Model Higgs Boson with the L3 Experiment at LEP", Phys. Lett. B 517 (2001) 319