Proton Form Factors Measurements in the Time-Like Region

Conference · Mon Oct 22 04:00:00 EDT 2007 · J.Phys.Conf.Ser.69:012014,2007

DOI:https://doi.org/10.1088/1742-6596/69/1/012014· OSTI ID:918536

Anulli, F

I present an overview of the measurement of the proton form factors in the time-like region. BABAR has recently measured with great accuracy the e{sup +}e{sup -} {yields} p{bar p} reaction from production threshold up to an energy of {approx} 4.5 GeV, finding evidence for a ratio of the electric to magnetic form factor greater than unity, contrary to expectation. In agreement with previous measurements, BABAR confirmed the steep rise of the magnetic form factor close to the p{bar p} mass threshold, suggesting the possible presence of an under-threshold N{bar N} vector state. These and other open questions related to the nucleon form factors both in the time-like and space-like region, wait for more data with different experimental techniques to be possibly solved.

• Research Organization: Stanford Linear Accelerator Center (SLAC)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 918536
• Report Number(s): SLAC-PUB-12901
• Conference Information: Journal Name: J.Phys.Conf.Ser.69:012014,2007 Journal Volume: 69
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ACCURACY
Experiment-HEP
HEPEX
FORM FACTORS
NUCLEONS
PHYSICS
PRODUCTION
PROTONS
VECTORS