USE OF PI P ---> PI PI N REACTIONS TO STUDY PI PI SCATTERING IN THE ELASTIC INTERACTION REGION

Alekseeva, E.a. ; Kartamyshev, A.a. ; Makarin, V.k. ; et al.
Sov.Phys.JETP 55 (1982) 591-600, 1982.
Inspire Record 185170 DOI 10.17182/hepdata.2406
2 data tables match query

No description provided.

No description provided.


The Process e+ e- ---> omega pi0 ---> pi0 pi0 gamma up to 1.4-GeV

Achasov, M.N. ; Beloborodov, K.I. ; Berdyugin, A.V. ; et al.
Phys.Lett.B 486 (2000) 29-34, 2000.
Inspire Record 527752 DOI 10.17182/hepdata.41747

The cross section of the $e^+e^-\to\omega\pi^0\to\pi^0\pi^0\gamma$ reaction was measured by the SND detector at VEPP-2M $e^+e^-$ collider in the energy range from threshold up to 1.4 GeV. Results of the cross section fitting by the sum of $\rho$, $\rho^{\prime}$ and $\rho^{\prime\prime}$ contributions are presented.

1 data table match query

Only statistical errors are presented.


The $e^+e^- \to 3(\pi^+ \pi^-), 2(\pi^+ \pi^- \pi^0)$ and $K^+ K^- 2(\pi^+ \pi^-)$ cross sections at center-of-mass energies from production threshold to 4.5-GeV measured with initial-state radiation

The BaBar collaboration Aubert, Bernard ; Barate, R. ; Boutigny, D. ; et al.
Phys.Rev.D 73 (2006) 052003, 2006.
Inspire Record 709730 DOI 10.17182/hepdata.41843

We study the processes e+ e- --> 3(pi+pi-)gamma, 2(pi+pi-pi0)gamma and K+ K- 2(pi+pi-)gamma, with the photon radiated from the initial state. About 20,000, 33,000 and 4,000 fully reconstructed events, respectively, have been selected from 232 fb-1 of BaBar data. The invariant mass of the hadronic final state defines the effective e+e- center-of-mass energy, so that these data can be compared with the corresponding direct e+e- measurements. From the 3(pi+pi-), 2(pi+pi-pi0) and K+ K- 2(pi+pi-) mass spectra, the cross sections for the processes e+ e- --> 3(pi+pi-), e+ e- --> 2(pi+pi-pi0) and e+ e- --> K+ K- 2(pi+pi-) are measured for center-of-mass energies from production threshold to 4.5 GeV. The uncertainty in the cross section measurement is typically 6-15%. We observe the J/psi in all these final states and measure the corresponding branching fractions.

2 data tables match query

The cross section for E+ E- --> 3PI+ 3PI- as measured with the ISR data. Errors are statistical only.

The cross section for E+ E- --> 2PI+ 2PI- 2PI0 as measured with the ISR data. Errors are statistical only.


Measurement of the pion form-factor in the range 1.04-GeV to 1.38-GeV with the CMD-2 detector

The CMD-2 collaboration Aul'chenko, V.M. ; Akhmetshin, R.R. ; Banzarov, V.Sh. ; et al.
JETP Lett. 82 (2005) 743-747, 2005.
Inspire Record 712216 DOI 10.17182/hepdata.41807

The cross section for the process $e^+e^-\to\pi^+\pi^-$ is measured in the c.m. energy range 1.04-1.38 GeV from 995 000 selected collinear events including 860000 $e^+e^-$ events, 82000 $\mu^+\mu^-$ events, and 33000 $\pi^+\pi^-$ events. The systematic and statistical errors of measuring the pion form factor are equal to 1.2-4.2 and 5-13%, respectively.

1 data table match query

Measured value of the pion form factor with statistical errors only.


Study of the process e+ e- ---> omega pi0 ---> pi0 pi0 gamma in c.m. energy range 920-MeV - 1380-MeV at CMD-2

The CMD-2 collaboration Akhmetshin, R.R. ; Aulchenko, V.M. ; Banzarov, V.Sh. ; et al.
Phys.Lett.B 562 (2003) 173-181, 2003.
Inspire Record 616446 DOI 10.17182/hepdata.41951

The cross section of the process e+ e- --> omega pi0 --> pi0 pi0 gamma has been measured in the c.m. energy range 920-1380 MeV with the CMD-2 detector. Its energy dependence is well described by the interference of the rho(770) and rho'(1450) mesons decaying to omega pi0. Upper limits for the cross sections of the direct processes e+ e- --> pi0 pi0 gamma, eta pi0 gamma have been set.

1 data table match query

Measurement of the Born cross section and the 'Bare' cross section of the process E+ E- --> OMEGA < PI0 GAMMA > PI0.


Study of the process e+e-\to \mu+\mu- in the energy region \sqrt{s}=980, 1040 -- 1380 MeV

Achasov, M.N. ; Aulchenko, V.M. ; Beloborodov, K.I. ; et al.
Phys.Rev.D 79 (2009) 112012, 2009.
Inspire Record 798415 DOI 10.17182/hepdata.50493

The cross section of the process e+e-\to\mu+\mu- was measured in the SND experiment at the VEPP-2M e+e- collider in the energy region \sqrt{s}=980, 1040 -- 1380 MeV. The event numbers of the process e+e-\to\mu+\mu- were normalized to the integrated luminosity measured using e+e-\to e+e- and e+e-\to\gamma\gamma processes. The ratio of the measured cross section to the theoretically predicted value is 1.006\pm 0.007 \pm 0.016 and 1.005 \pm 0.007 \pm 0.018 in the first and second case respectively. Using results of the measurements, the electromagnetic running coupling constant \alpha in the energy region \sqrt{s}=1040 -- 1380 MeV was obtained <1/\alpha> = 134.1\pm 0.5 \pm 1.2 and this is in agreement with theoretical expectation.

2 data tables match query

The E+ E- --> MU+ MU- cross section obtained using the (GAMMA GAMMA) luminosity measurement.

The measured E+ E- --> E+ E- cross section in the electron angle 30 to 150 degrees.


a(1)(1260) pi dominance in the process e+ e- ---> 4 pi at energies 1.05-GeV - 1.38-GeV

The CMD-2 collaboration Akhmetshin, R.R. ; Anashkin, E.V. ; Arpagaus, M. ; et al.
Phys.Lett.B 466 (1999) 392-402, 1999.
Inspire Record 483994 DOI 10.17182/hepdata.50145

First results of the study of the process e+e- \to 4\pi by the CMD-2 collaboration at VEPP-2M are presented for the energy range 1.05--1.38 GeV. Using an integrated luminosity of 5.8 pb^{-1}, energy dependence of the processes e+e- \to \pi^+\pi^- 2\pi^0 and e+e- \to 2\pi^+ 2\pi^- has been measured. Analysis of the differential distributions demonstrates the dominance of the a_1\pi and \omega\pi intermediate states. Upper limits for the contributions of other alternative mechanisms are also placed.

3 data tables match query

Energy dependence of the cross section for the 2PI+ 2PI- final state. Statistical errors only.

Energy dependence of the cross section for the PI+ PI- 2PI0 final state. Statistical errors only.

Energy dependence of the cross section for the OMEGA PI0 final state. Statistical errors only.


Experiments at VEPP-2M with SND detector

The SND collaboration Achasov, M.N. ; Aulchenko, V.M. ; Baru, S.E. ; et al.
1998.
Inspire Record 476386 DOI 10.17182/hepdata.50374

Short overview of experiments with SND detector at VEPP-2M e^+e^- collider in the energy range 2E = 400 - 1400 MeV and preliminary results of data analysis are presented.

3 data tables match query

No description provided.

No description provided.

No description provided.


Measurement of the e+e- -> K+K- process cross-section in the energy range s**(1/2) = 1.04 - 1.38 GeV with the SND detector in the experiment at VEPP-2M e+e- collider

Achasov, M.N. ; Beloborodov, K.I. ; Berdyugin, A.V. ; et al.
Phys.Rev.D 76 (2007) 072012, 2007.
Inspire Record 755881 DOI 10.17182/hepdata.51605

The cross section for the process $e^+e^- \to K^+K^-$ was measured in the energy range $\sqrt{s}$ = 1.04--1.38 GeV in the SND experiment at VEPP-2M $e^+e^-$ collider. The measured cross section is described by the Vector Meson Dominance model with contributions from the light vector mesons $\rho$, $\omega$, $\phi$ and their lowest excitations. The mean statistical accuracy of the measurement is 4.4 %, and the systematic uncertainty is 5.2 %.

1 data table match query

The measured cross section and charged kaon form factor.


POLARIZATION OF RECOIL PROTONS FROM THE REACTION GAMMA P ---> PI0 P IN THE PHOTON ENERGY RANGE 450-MEV - 800-MEV

Bratashevsky, A.S. ; Gorbenko, V.G. ; Derebchinsky, A.I. ; et al.
Nucl.Phys.B 166 (1980) 525-533, 1980.
Inspire Record 157933 DOI 10.17182/hepdata.34552

Measurement of secondary-proton polarization from the reaction γ p → π 0 p have been performed in the proton energy range 500–800 MeV at c.m. pion emission angles 100°, 120°, 140°. The experiment was carried out using an optical spark chamber telescope at the output of the magnetic spectrometer. The obtained experimental data are included in a Walker-type analysis in order to verify the parameters of the resonances P 11 (1470), D 13 (1570) and S 11 (1535). Proton polarization in the reaction γ p → π 0 p was measured for a photon energy of 450 MeV at a c.m. pion emission angle of 105° using photons linearly polarized at 45° to the reaction plane. A liquid hydrogen target in the field of a superconducting magnet was used for the separation of the P x ′ and P z ′ components of the secondary-proton polarization vector.

1 data table match query

No description provided.