Measurement of the proton form factor in the time-like region

An experiment (LEAR: PS170) has been designed to detect the annihilation of antiprotons in electron-positron pairs. It aims to measure the proton form factor in the time-ike region and to observe the spectrum of vector mesons between 1 and 1.6 GeV

Status and future of the experiment PS170

The LEAR experiment PS170 is designed to detect the e+e- pairs from pbar annihilation. Data have been taken at 300, 600 and 1500 MeV/c incident momenta. The analysis of the 300 MeV/c data gave 200 2-body events clearly separated from the hadronic background

Study of p pbar in e+ e- reaction at rest

Preliminary results on e+e- pair production in pbar p annihilation of PS170 experiment at LEAR at CERN are presente

Determination of the electric and magnetic form factors of the proton in the time-like region

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Electron-positron pair production in p pbar annihilation at LEAR

The preliminary results of the PS170 experiment, installed on the LEAR beam, at CERN, are reported here. Annihilihations at rest and with antiproton momentum ranging from 100 to 290 MeV/c have been collected in the first run of the experiment

A large solid angle magnetic detector for precision studies of e.m. processes in low energy pbar interactions

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"Playdoyer" for a charmonium spectroscopy at SuperLEAR

We think the construction of a new antiproton storage ring at CERN, with a momentum of circulating particles from 2 up to 7 GeV/c, would lead to an important progress in our understanding of strong interactions. As an example a quantitative charmonium spectroscopy and the search for "exotic" heavy states (c cbar g, cq - cbar qbar, gg) are discussed in the framework of the detection of the e+e- pairs (J/psi or psi' probe)

Latest results from FENICE

The FENICE apparatus to measure the electromagnetic form factor of the neutron was built at the ADONE storage ring in Frascati and the reaction e+ e- > n nbar has been studied in the energy region between the threshold and 2.44 GeV in the center of mass. Preliminary results at 2.0 and 2.1 GeV have already been reported. New results are now available that confirm the eletromagnetic form factor of the neutron |Gn| not lower that proton form factor |Gp|

Measurement of the electromagnetic form factor of the proton in the time-like region

The cross section for the process e+e- >> p pbar has been measured in the s range 3.6–5.9 GeV2 by the FENICE experiment at the e+e− Adone storage ring and the proton electromagnetic form factor has been extracted

Some final results from the FENICE experiment

The first measurement of the neutron form factor in the time-like region has been produced in tha Fenice experiment by studying the e+ e- > n nbar reaction at the Adone storage ring.The most recent results at the energies of 1.92, 2.0, 2.1 GeV in the center of mass are reported in this paper