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Determination of the Charged Pion Form Factor at Q**2 = 1.60 and 2.45-(GeV/c)**2

The Jefferson Lab F(pi)-2 collaboration Horn, T. ; Aniol, K. ; Arrington, J. ; et al.
Phys.Rev.Lett. 97 (2006) 192001, 2006.
Inspire Record 721062 DOI 10.17182/hepdata.31560

The H(e,e'pi+)n cross section was measured at four-momentum transfers of Q2=1.60 and 2.45 GeV2 at an invariant mass of the photon nucleon system of W=2.22 GeV. The charged pion form factor (F_pi) was extracted from the data by comparing the separated longitudinal pion electroproduction cross section to a Regge model prediction in which F_pi is a free parameter. The results indicate that the pion form factor deviates from the charge-radius constrained monopole form at these values of Q2 by one sigma, but is still far from its perturbative Quantum Chromo-Dynamics prediction.

3 data tables

Separated cross sections at mean Q**2 of 1.60 GeV**2.

Separated cross sections at mean Q**2 of 2.45 GeV**2.

Extracted values of the charged pion form-factor. Errors are the statistical and experimental systematics combined in quadrature.


Measurement of the eta and eta-prime transition form-factors at q**2 = 112-GeV**2

The BaBar collaboration
Phys.Rev. D74 (2006) 012002, 2006.
Inspire Record 716277 DOI 10.17182/hepdata.22085

We report a study of the processes e+e- -> eta gamma and e+e- -> etaprime gamma at a center-of-mass energy of 10.58 GeV, using a 232 fb^-1 data sample collected with the BABAR detector at the PEP-II collider at SLAC. We observe 20+6-5 eta gamma and 50+8-7 etaprime gamma events over small backgrounds, and measure the cross sections sigma(e+e- -> eta gamma) =4.5+1.2-1.1(stat)+-0.3(sys) fb and sigma(e+e- -> etaprime gamma)=5.4+-0.8(stat)+-0.3(sys) fb. The corresponding transition form factors at q^2 = 112 GeV^2 are q^2|F_eta(q^2)|=0.229+-0.030+-0.008 GeV, and q^2|F_etaprime(q^2)|=0.251+-0.019+-0.008 GeV, respectively.

3 data tables

Measured cross sections.

Undressed cross sections calculated by applying a 7.5 +- 0.2 PCT correction for vacuum polarization.

Transition form factors at Q**2 = 112 GeV**2.


Precise determination of the electromagnetic form-factor of the proton in the timelike region up to s = 4.2-GeV**2

Bardin, G. ; Burgun, G. ; Calabrese, R. ; et al.
Phys.Lett. B257 (1991) 514-518, 1991.
Inspire Record 314621 DOI 10.17182/hepdata.48504
3 data tables

No description provided.

No description provided.

Results of one-parameter fit. |Ge|=|Gm| assumed.


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

Bardin, G. ; Burgun, G. ; Calabrese, R. ; et al.
Nucl.Phys. B411 (1994) 3-32, 1994.
Inspire Record 376134 DOI 10.17182/hepdata.32865
6 data tables

No description provided.

No description provided.

No description provided.

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Precision measurement of the neutron magnetic form-factor

Anklin, H. ; Fritschi, D. ; Jourdan, J. ; et al.
Phys.Lett. B336 (1994) 313-318, 1994.
Inspire Record 384757 DOI 10.17182/hepdata.28730
5 data tables

Using kinematics I.

Using kinematics II.

Using kinematics I. SD is simple dipole model.

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

Antonelli, A. ; Baldini, R. ; Bertani, M. ; et al.
Phys.Lett. B334 (1994) 431-434, 1994.
Inspire Record 377833 DOI 10.17182/hepdata.28572
2 data tables

Cross section measurement.

Proton form-factor measurement.


Measurements of the proton elastic form-factors for 1-GeV/c**2 <= Q**2 <= 3-GeV/C**2 at SLAC

Walker, R.C. ; Filippone, B. ; Jourdan, J. ; et al.
Phys.Rev. D49 (1994) 5671-5689, 1994.
Inspire Record 360764 DOI 10.17182/hepdata.22469
6 data tables

Point-to-point systematic uncertainty is 0.5%, overall normailzation uncertainty is 1.9%.

Point-to-point systematic uncertainty is 0.5%, overall normailzation uncertainty is 1.9%.

Point-to-point systematic uncertainty is 0.5%, overall normailzation uncertainty is 1.9%.

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Evidence for spin one resonance production in the reaction gamma gamma* ---> pi+ pi- pi0 pi0

The TPC/Two Gamma collaboration Bauer, Daniel A. ; Belcinski, R. ; Berg, R.C. ; et al.
Phys.Rev. D48 (1993) 3976-3987, 1993.
Inspire Record 353748 DOI 10.17182/hepdata.22574
2 data tables

No description provided.

Coupling parameter times the effective form factor.


First measurement of the neutron electromagnetic form-factor in the timelike region

Antonelli, A. ; Baldini, R. ; Bertani, M. ; et al.
Phys.Lett. B313 (1993) 283-287, 1993.
Inspire Record 359376 DOI 10.17182/hepdata.28867
2 data tables

Neutron form factor and cross section.

Preliminary analysis of proton form factor and cross section.


Measurements of the electric and magnetic form-factors of the neutron from Q**2 = 1.75-GeV/c**2 to 4-GeV/c**2

Lung, A. ; Stuart, L.M. ; Bosted, Peter E. ; et al.
Phys.Rev.Lett. 70 (1993) 718-721, 1993.
Inspire Record 342252 DOI 10.17182/hepdata.19739
2 data tables

Magnetic form factors.

Electric form factors.


Measurements of the electric and magnetic form-factors of the proton from Q**2 = 1.75-GeV/c**2 to 8.83-GeV/c**2

Bosted, Peter E. ; Clogher, L. ; Lung, A. ; et al.
Phys.Rev.Lett. 68 (1992) 3841-3844, 1992.
Inspire Record 332962 DOI 10.17182/hepdata.19849
2 data tables

Magnetic form factors.

Electric form factors.


Measurement of the proton electromagnetic form-factors in the timelike region at $8.9-GeV^{2} - 13-GeV^{2}$

The E760 collaboration Armstrong, T.A. ; Bettoni, D. ; Bharadwaj, V. ; et al.
Phys.Rev.Lett. 70 (1993) 1212-1215, 1993.
Inspire Record 340584 DOI 10.17182/hepdata.19781
5 data tables

No description provided.

No description provided.

No description provided.

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The Pion Electromagnetic Form-factor in the Timelike Energy Range 1.35-{GeV} $\le \sqrt{s} \le$ 2.4-{GeV}

The DM2 collaboration Bisello, D. ; Busetto, G. ; Castro, A. ; et al.
Phys.Lett. B220 (1989) 321-327, 1989.
Inspire Record 267118 DOI 10.17182/hepdata.29829
1 data table

Statistical errors only.


Measurement of the Pion Form-factor in the Timelike Region for $q^2$ Values Between .1-{GeV}/$c^2$ and .18-{GeV}/$c^2$

Amendolia, S.R. ; Badelek, B. ; Batignani, G. ; et al.
Phys.Lett. B138 (1984) 454-458, 1984.
Inspire Record 195944 DOI 10.17182/hepdata.30572
1 data table

No description provided.


Study of the Reaction $e^+ e^- \to K^+ K^-$ in the Energy Range 1350 $\le \sqrt{s} \le$ 2400-{MeV}

The DM2 collaboration Bisello, D. ; Busetto, G. ; Castro, A. ; et al.
Z.Phys. C39 (1988) 13, 1988.
Inspire Record 262690 DOI 10.17182/hepdata.15622

Thee+e−→K+K− cross section has been measured from about 750 events in the energy interval\(1350 \leqq \sqrt s\leqq 2400 MeV\) with the DM2 detector at DCI. TheK± form factor |FF±| cannot be explained by the ρ, ω, ϕ and ρ′(1600). An additional resonant amplitude at 1650 MeV has to be added as suggested by a previous experiment.

2 data tables

No description provided.

No description provided.


MEASUREMENT OF THE FORM-FACTOR FOR THE DECAY K- ---> PI0 E- ANTI-NEUTRINO

Bolotov, V.N. ; Gninenko, S.N. ; Dzhilkibaev, R.M. ; et al.
JETP Lett. 47 (1988) 7-11, 1988.
Inspire Record 271435 DOI 10.17182/hepdata.16819
1 data table

No description provided.


DETERMINATION OF NUCLEON FORM-FACTOR ON THE BASIS OF DATA FROM pi+ Li-7 ---> e+ e- X REACTION AT 380-MeV KINETIC PION ENERGY

Baturin, V.N. ; Blokhintseva, T.D. ; Kravtsov, A.V. ; et al.
Sov.J.Nucl.Phys. 47 (1988) 452, 1988.
Inspire Record 246879 DOI 10.17182/hepdata.38971
1 data table

No description provided.


Measurement of the electron-Positron Annihilation Cross-Section Into pi+ pi- at the Energies 915-MeV, 990-MeV and 1076-MeV

Cosme, G. ; Courau, A. ; Dudelzak, B. ; et al.
No Journal Information, 1976.
Inspire Record 109771 DOI 10.17182/hepdata.38244
1 data table

No description provided.


Measurement of the $\pi^-$ Form-factor

Dally, E.B. ; Drickey, Darrell James ; Hauptman, J.M. ; et al.
Phys.Rev. D24 (1981) 1718-1735, 1981.
Inspire Record 172687 DOI 10.17182/hepdata.26467

An experiment to measure the electromagnetic form factor of the negative π meson has been carried out at Fermilab by elastically scattering 100-GeV/c pions from the atomic electrons in a liquid-hydrogen target. We find that the elastic differential scattering cross section is characterized by a root-mean-square pion charge radius of 0.56±0.04 fm. This paper described our experimental design, measurement resolutions, event triggering logic, event reconstruction, experimental corrections, and form-factor results.

3 data tables

No description provided.

Axis error includes +- 0.54/0.54 contribution (EVENT-FINDING CORRECTIONS).

No description provided.


Elastic Scattering Measurement of the Negative Pion Radius

Dally, E.B. ; Hauptman, J.M. ; Kubic, J. ; et al.
Phys.Rev.Lett. 48 (1982) 375-378, 1982.
Inspire Record 177923 DOI 10.17182/hepdata.20609

A new measurement of the elastic scattering of 250-GeV/c negative pions by electrons provides form-factor results from 0.0368<q2<0.0940 (GeV/c)2. These measurements determine the mean square pion radius to be 〈rπ2〉=0.439±0.030 fm2 or 〈rπ2〉12=0.663±0.023 fm. Comparisons are made with previous elastic-scattering experiments as well as with results obtained from electroproduction experiments, e+e− annihilation experiments, and phenomenological analyses.

1 data table

No description provided.


OBSERVATION OF INVERSE ELECTROPRODUCTION OF PIONS ON C-12 NUCLEUS AT 164-MeV PION ENERGY AND DETERMINATION OF F1(v) NUCLEON FORM-FACTOR

Alekseev, G.D. ; Blokhintseva, T.D. ; Karpukhin, V.V. ; et al.
Sov.J.Nucl.Phys. 46 (1987) 801, 1987.
Inspire Record 247868 DOI 10.17182/hepdata.38865
3 data tables

No description provided.

No description provided.

No description provided.


Magnetic form-factor of the deuteron

Auffret, S. ; Cavedon, J.M. ; Clemens, J.C. ; et al.
Phys.Rev.Lett. 54 (1985) 649-652, 1985.
Inspire Record 214266 DOI 10.17182/hepdata.20337
2 data tables

No description provided.

No description provided.


Measurement of Elastic electron - Neutron Cross-Sections Up to Q**2 = 10-(GeV/c)**2

Rock, Stephen ; Arnold, R.G. ; Bosted, Peter E. ; et al.
Phys.Rev.Lett. 49 (1982) 1139, 1982.
Inspire Record 179135 DOI 10.17182/hepdata.20575
2 data tables

No description provided.

No description provided.


A Measurement of the Pion Charge Radius

Amendolia, S.R. ; Badelek, B. ; Batignani, G. ; et al.
Phys.Lett. B146 (1984) 116-120, 1984.
Inspire Record 201598 DOI 10.17182/hepdata.30511
1 data table

Errors are statistical only.


A Measurement of the Kaon Charge Radius

Amendolia, S.R. ; Batignani, G. ; Beck, G.A. ; et al.
Phys.Lett. B178 (1986) 435-440, 1986.
Inspire Record 231129 DOI 10.17182/hepdata.30242
1 data table

Ratio is assumed free of systematic error.