Lehmann, P.
Single Differential Cross Section
FORMFACTOR
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rivet Analysis
Measurement of $\sigma(e^+e^-\to\pi^+\pi^-\gamma(\gamma))$ and the dipion contribution to the muon anomaly with the KLOE detector

The KLOE collaboration Ambrosino, F. ; Antonelli, A. ; Antonelli, M. ; et al.
Phys.Lett.B 670 (2009) 285-291, 2009.
Inspire Record 797438 DOI 10.17182/hepdata.57088

We have measured the cross section $\sigma(e^+e^-\to\pi^+\pi^-\gamma(\gamma))$ at DA$\Phi$NE, the Frascati \phi-factory, using events with initial state radiation photons emitted at small angle and inclusive of final state radiation. We present the analysis of a new data set corresponding to an integrated luminosity of 240 pb$^{-1}$. We have achieved a reduced systematic uncertainty with respect to previously published KLOE results. From the cross section we obtain the pion form factor and the contribution to the muon magnetic anomaly from two pion states in the mass range $0.592 < M_{\pi\pi} < 0.975$ GeV. For the latter we find $\Delta a^{\pi\pi}_\mu = (387.2\pm0.5_{\rm stat}\pm2.4_{\rm exp}\pm2.3_{\rm th})\times 10^{-10}$

3 data tables
Table 1

Differential cross section for E+ E- --> PI+ PI- GAMMA (GAMMA).

Table 2

Total cross section for E+ E- --> PI+ PI-.

Table 3

Pion form factor.


rivet Analysis
Measurement of sigma(e+ e- --> pi+ pi- gamma) and extraction of sigma(e+ e- --> pi+ pi-) below 1-GeV with the KLOE detector.

The KLOE collaboration Aloisio, A. ; Ambrosino, F. ; Antonelli, A. ; et al.
Phys.Lett.B 606 (2005) 12-24, 2005.
Inspire Record 655225 DOI 10.17182/hepdata.41901

We have measured the cross section $\sigma(e^+e^-\to \pi^+\pi^- \gamma)$ at an energy $W=m_\phi=1.02$ GeV with the KLOE detector at the electron-positron collider DA$\Phi$NE. From the dependence of the cross section on the invariant mass of the two-pion system, we extract $\sigma(e^+e^-\to \pi^+\pi^-)$ for the mass range $0.35<s<0.95$ GeV$^2$. From this result, we calculate the pion form factor and the hadronic contribution to the muon anomaly, $a_\mu$.

3 data tables
Table 1

The differential cross section as a function of the invariant mass of the di-pion system in the angular region THETA(PIPI) <15 DEGREES or THETA(PIPI) >165 DEGREES and THETA(PI) in the region 0 to 180 DEGREES.

Table 2

The physical cross section for E+ E- --> PI+ PI- including FSR and vacuum polarization effects.

Table 3

The pion form factor with FSR and vacuum polarization effects removed.


A STUDY OF e+ e- ANNIHILATION IN THE 1400-MeV TO 2250-MeV ENERGY RANGE WITH THE MAGNETIC DETECTOR DM2 AT DCI

Augustin, J.E. ; Ayach, L. ; Calcaterra, A. ; et al.
LAL-83-21, 1983.
Inspire Record 192321 DOI 10.17182/hepdata.13242

None

5 data tables
Table 1

ASSUMING ABS(GE)=ABS(GM).

Table 2

No description provided.

Table 3

No description provided.

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Electromagnetic Form-Factors of the Proton at Low Four-Momentum Transfer

Borkowski, F. ; Peuser, P. ; Simon, G.G. ; et al.
Nucl.Phys.B 93 (1975) 461-478, 1975.
Inspire Record 850 DOI 10.17182/hepdata.31992

The 300 MeV electron linear accelerator of Mainz has been used to measure the angular dependence of the electron-proton elastic scattering cross sections at seven different energies for squared four-momentum transfers between 0.13 and 4.7 fm −2 . The proton form factors have been extracted from the cross sections by means of Rosenbluth plots and by fitting parametrized analytical functions directly to the cross sections. The best fit is compared to the data of other laboratories. The previously reported deviations from the dipole fit have been confirmed. From the form factors at q 2 <0.9 fm 2 the proton r.m.s. radius has been determined. A determination of the spectral function of the nucleon isovector form factor G E V in the time-like is obtained using a realistic ϱ resonance.

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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