Study of e+e- --> p anti-p via initial-state radiation at BABAR
J.P. Lees
(1)
,
V. Poireau
(1)
,
V. Tisserand
(1)
,
D. Bernard
(2)
,
M. Verderi
(2)
,
N. Arnaud
(3)
,
M. Davier
(3)
,
D. Derkach
(3)
,
G. Grosdidier
(3)
,
F. Le Diberder
(3)
,
A.M. Lutz
(3)
,
B. Malaescu
(3)
,
P. Roudeau
(3)
,
M.H. Schune
(3)
,
A. Stocchi
(3)
,
G. Wormser
(3)
,
S. Akar
(4)
,
E. Ben-Haim
(4)
,
M. Bomben
(4)
,
G.R. Bonneaud
(4)
,
H. Briand
(4)
,
G. Calderini
(4)
,
J. Chauveau
(4)
,
O. Hamon
(4)
,
Ph. Leruste
(4)
,
G. Marchiori
(4)
,
J. Ocariz
(4)
,
S. Sitt
(4)
N. Arnaud
- Function : Author
- PersonId : 16841
- IdHAL : nicolas-arnaud
- ORCID : 0000-0001-6589-8673
M. Bomben
- Function : Author
- PersonId : 1380362
- ORCID : 0000-0002-9807-861X
- IdRef : 242005462
G. Calderini
- Function : Author
- PersonId : 10608
- IdHAL : giovanni-calderini
- ORCID : 0000-0002-9495-9145
- IdRef : 172243211
G. Marchiori
- Function : Author
- PersonId : 741274
- IdHAL : giovanni-marchiori
- ORCID : 0000-0003-2655-7643
- IdRef : 180997203
Abstract
The process e+e- --> p anti-p gamma is studied using 469 fb-1 of integrated luminosity collected with the BABAR detector at the PEP-II collider, at an e+e- center-of-mass energy of 10.6 GeV. From the analysis of the p anti-p invariant mass spectrum, the energy dependence of the cross section for e+e- --> p anti-p is measured from threshold to 4.5 GeV. The energy dependence of the ratio of electric and magnetic form factors, |G_E/G_M|, and the asymmetry in the proton angular distribution are measured for p anti-p masses below 3 GeV. We also measure the branching fractions for the decays J/psi --> p anti-p and psi(2S) --> p anti p.