Pennington, M.R.
[1.0, 2.0]
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rivet Analysis
Pion and kaon pair production in photon-photon collisions

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.
Phys.Rev.Lett. 57 (1986) 404, 1986.
Inspire Record 228072 DOI 10.17182/hepdata.20204

We report measurements of the two-photon processes e+e−→e+e−π+π− and e+e−→e+e−K+K−, at an e+e− center-of-mass energy of 29 GeV. In the π+π− data a high-statistics analysis of the f(1270) results in a γγ width Γ(γγ→f)=3.2±0.4 keV. The π+π− continuum below the f mass is well described by a QED Born approximation, whereas above the f mass it is consistent with a QCD-model calculation if a large contribution from the f is assumed. For the K+K− data we find agreement of the high-mass continuum with the QCD prediction; limits on f′(1520) and θ(1720) formation are presented.

5 data tables
Table 1

Data read from graph. Additional overall systematic error 20% not included.

Table 2

Data read from graph.. Additional overall systematic error 20% not included.

Table 3

Data read from graph.. Additional overall systematic error 20% not included.. The Q**2 dependence is normalized to unity for the bin centred on Q**2 = 0.

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EXCLUSIVE PRODUCTION OF K+ K- pi+ pi- IN PHOTON-PHOTON COLLISIONS

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Armitage, J.C. ; et al.
Phys.Rev.Lett. 54 (1985) 2564, 1985.
Inspire Record 213402 DOI 10.17182/hepdata.20345

We report a measurement of the reaction γγ→K+K−π+π− in both tagged and untagged events at PEP. The cross section rises with invariant γγ mass to about 15 nb at 2 GeV and falls slowly at higher masses. We find clear evidence for the processes γγ→φπ+π− and γγ→K*0(892)Kπ. Upper limits (95% C.L.) of 1.5 and 5.7 nb in the mass range from 1.7 to 3.7 GeV are obtained for φρ0 and K*0K¯*0 production, respectively.

8 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Untagged sample, (non-resonant).

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Measurement of asymmetry in spin dependent e p resonance region scattering.

Baum, Guenter ; Bergstrom, M.R. ; Clendenin, J.E. ; et al.
Phys.Rev.Lett. 45 (1980) 2000, 1980.
Inspire Record 154062 DOI 10.17182/hepdata.20698

The first measurements are reported of the asymmetry in resonance-region scattering of longitudinally polarized electrons by longitudinally polarized protons. Data have been obtained at Q2=0.5 and 1.5 (GeV/c)2 in the missing-mass range W=1.1−1.9 GeV. Results are compatible with a multipole analysis of single-pion electroproduction. The spin-dependent behavior is consistent with a duality mechanism as in the unpolarized case.

4 data tables
Table 1

ELECTRON ASYMMETRY AT Q**2 ABOUT 0.5 GEV**2.

Table 2

ELECTRON ASYMMETRY AT Q**2 ABOUT 1.5 GEV**2.

Table 3

PHOTON ASYMMETRY AT Q**2 ABOUT 0.5 GEV**2.

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Proton form factors from elastic electron-proton scattering

Janssens, T. ; Hofstadter, R. ; Hughes, E.B. ; et al.
Phys.Rev. 142 (1966) 922-931, 1966.
Inspire Record 49127 DOI 10.17182/hepdata.26698

Absolute measurements of the elastic electron-proton cross section have been made with a precision of about 4% for values of the square of the four-momentum transfer, q2, in the range 6.0 to 30.0 F−2 and for electron scattering angles in the range 45° to 145°. To within the experimental errors, it is found that the charge and magnetic form factors of the proton have a common dependence on q2 when normalized to unity at q2=0, and that an accurate representation of the behavior of the form factor and that of the cross sections themselves can be given in terms of a three-pole approximation to the dispersion theory of nucleon form factors.

27 data tables
Table 1

Axis error includes +- 2./2. contribution (RANDOM ERROR).

Table 2

Axis error includes +- 2./2. contribution (RANDOM ERROR).

Table 3

Axis error includes +- 2./2. contribution (RANDOM ERROR).

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