Measurement of the proton electromagnetic form-factor near threshold in the timelike region

Bardin, G.; Burgun, G.; Calabrese, R.; Capon, G.; Carlin, R.; Dalpiaz, P.; Dalpiaz, P.F.; de Brion, J.P.; Derre, J.; Dosselli, U.

doi:10.1016/0370-2693(91)91157-Q

Measurement of the proton electromagnetic form-factor near threshold in the timelike region

G. Bardin
(
- Saclay
)
,
G. Burgun
(
- Saclay
)
,
R. Calabrese
(
- Ferrara U. and
- INFN, Ferrara
)
,
G. Capon
(
- Frascati
)
,
R. Carlin
(
- INFN, Padua and
- Padua U.
)

1991

6 pages

Published in:

Phys.Lett.B 255 (1991) 149-154

Published: 1991

DOI:

10.1016/0370-2693(91)91157-Q

View in:

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Abstract: (Elsevier)

The rate of the reaction p ̄ p → e + e − has been measured in liquid hydrogen for antiprotons at momentum values between 150 and 300 MeV/ c . New precise values of the proton electromagnetic form factor in the time-like region have been obtained assuming | G e |=| G m | in the investigated region. The q 2 dependence of the form factor close to threshold is found to have a steeper slope than indicated by existing calculations based on vector dominance models.

anti-p p: exclusive reaction
anti-p p: annihilation
annihilation: anti-p p
hydrogen: liquid
electron: pair production
pair production: electron
p: form factor
form factor: p
experimental results
CERN LEAR

References(18)

Figures(0)

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