Date

Study of dynamics of the process $e^+e^-\to \pi^+\pi^-\pi^0$ in the energy range 1.15--2.00 GeV

The SND collaboration Achasov, M.N. ; Barnyakov, A.Yu. ; Baykov, A.A. ; et al.
Eur.Phys.J.C 80 (2020) 993, 2020.
Inspire Record 1809286 DOI 10.17182/hepdata.151394

The dynamics of the process $ e^+e^- \to \pi^+\pi^-\pi^0 $ is studied in the energy region from 1.15 to 2.00 GeV using data accumulated with the SND detector at the VEPP-2000 $e^+e^-$ collider. The Dalitz plot distribution and $\pi^+\pi^-$ mass spectrum are analyzed in a model including the intermediate states $\rho(770)\pi$, $\rho(1450)\pi$, and $\omega\pi^0$. As a result, the energy dependences of the $\rho(770)\pi$ and $\rho(1450)\pi$ cross sections and the relative phases between the $\rho(770)\pi$ amplitude and the $\rho(1450)\pi $ and $\omega\pi^0$ amplitudes are obtained. The $\rho(1450)\pi$ cross section has a peak in the energy region of the $\omega(1650)$ resonance (1.55-1.75 GeV). In this energy range the contributions of the $\rho(770)\pi$ and $\rho(1450)\pi$ states are of the same order of magnitude. No resonance structure near 1.65 GeV is observed in the $\rho(770)\pi$ cross section. We conclude that the intermediate state $\rho(1450)\pi$ gives a significant contribution to the decay of $\omega (1650)\to\pi^+\pi^-\pi^0$, whereas the $\rho(770)\pi$ mechanism dominates in the decay $\omega(1420)\to\pi^+\pi^-\pi^0$.

3 data tables match query

The Born cross section of the process e+e- -> pi+pi-pi0, scan 2012.

The Born cross section of the process e+e- -> pi+pi-pi0, scan 2011.

The cross section of intermediate states rho pi0, rho' pi0, omega pi0 in the process e+e- -> pi+pi-pi0 extracted by the Dalitz plot analysis.


Study of the process e+e- to pi+pi-pi+pi-pi0 with CMD-2 detector

The CMD-2 collaboration Akhmetshin, R.R. ; Anashkin, E.V. ; Aulchenko, V.M. ; et al.
Phys.Lett.B 489 (2000) 125-130, 2000.
Inspire Record 532970 DOI 10.17182/hepdata.28019

The process e+e- to pi+ pi- pi+ pi- pi0 has been studied in the center of mass energy range 1280 -- 1380 MeV using 3.0 1/pb of data collected with the CMD-2 detector in Novosibirsk. Analysis shows that the cross section of the five pion production is dominated by the contributions of the eta pi+pi- and omega pi+pi- intermediate states.

3 data tables match query

Axis error includes +- 15/15 contribution.

Axis error includes +- 15/15 contribution.

Axis error includes +- 15/15 contribution.


Study of the Process e+ e- ---> eta gamma in c.m. Energy Range 600-1380 MeV at CMD-2

The CMD-2 collaboration Akhmetshin, R.R. ; Anashkin, E.V. ; Aulchenko, V.M. ; et al.
Phys.Lett.B 509 (2001) 217-226, 2001.
Inspire Record 554522 DOI 10.17182/hepdata.27025

The cross section of the process e+ e- ---> eta gamma has been measured in the 600-1380 MeV c.m. energy range with the CMD-2 detector. The following branching ratios have been determined: B(rho ---> eta gamma) = (3.28 +- 0.37 +- 0.23) 10^{-4}, B(omega ---> eta gamma) = (5.10 +- 0.72 +- 0.34) 10^{-4}, B(phi --> eta gamma) = (1.287 +- 0.013 +- 0.063) 10^{-2}. Evidence for the rho'(1450) ---> eta gamma decay has been obtained for the first time.

1 data table match query

The measured Born cross section for the ETA GAMMA final state.


Study of the Processes e+ e- --> eta gamma, e+ e- --> pi0 gamma --> 3 gamma in the c.m. Energy Range 600--1380 MeV at CMD-2

The CMD-2 collaboration Akhmetshin, R.R. ; Aulchenko, V.M. ; Banzarov, V.Sh. ; et al.
Phys.Lett.B 605 (2005) 26-36, 2005.
Inspire Record 658856 DOI 10.17182/hepdata.41864

The processes e+ e- --> eta gamma, e+ e- --> pi0 gamma --> 3 gamma have been studied in the c.m. energy range 600--1380 MeV with the CMD-2 detector. The following branching ratios have been determined: Br(rho --> eta gamma) = (3.21 +- 1.39 +- 0.20)x 10^{-4}; Br(omega --> eta gamma) = (4.44 + 2.29 -1.83 +- 0.28)x 10^{-4}; Br(phi --> eta gamma) = (1.373 +- 0.014 +- 0.085)x 10^{-2}; Br(rho --> pi0 gamma) = (6.21 +1.28 - 1.18 +- 0.39)x 10^{-4}; Br(omega --> pi0 gamma) = (9.06 +- 0.20 +- 0.57)x 10^{-2}; Br(phi --> pi0 gamma) = (1.258 +- 0.037 +- 0.077)x 10^{-3};

2 data tables match query

Born cross section for the process E+ E- --> ETA GAMMA.

Born cross section for the process E+ E- --> PI0 GAMMA.


Study of the Process e+ e- --> omega pi0 --> pi0 pi0 gamma in c.m. Energy Range 920--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 $e^+e^- \to K^0_L K^0_S$ in the C.M.Energy Range 1.05-1.38 GeV with CMD-2

Akhmetshin, R.R. ; Aulchenko, V.M. ; Banzarov, V.Sh. ; et al.
Phys.Lett.B 551 (2003) 27-34, 2003.
Inspire Record 601222 DOI 10.17182/hepdata.41971

The process $e^+e^- \to K^0_L K^0_S$ has been studied with the CMD-2 detector using about 950 events detected in the center-of-mass energy range from 1.05 to 1.38 GeV. The cross section exceeds the expectation based on the contributions of the rho(770), omega(782) and phi(1020) mesons only.

1 data table match query

Measured cross section and 'bare' cross section for the process E+ E- --> KL KS.


Pion-nucleon total cross-sections from 0.4 to 0.90 gev/c

Davidson, D. ; Bowen, T. ; Caldwell, P.K. ; et al.
Phys.Rev.D 6 (1972) 1199-1202, 1972.
Inspire Record 73938 DOI 10.17182/hepdata.22266

The total cross sections of π± on protons in the momentum interval from 0.40 to 0.90 GeV/c have been measured with high relative precision. In this interval the statistical error varies between 10 and 20 μb. No new structure is observed.

1 data table match query

No description provided.


Measurement of the Sigma- charge radius by Sigma- electron elastic scattering.

The SELEX collaboration Gough Eschrich, Ivo M. ; Kruger, H. ; Simon, J. ; et al.
Phys.Lett.B 522 (2001) 233-239, 2001.
Inspire Record 558329 DOI 10.17182/hepdata.42898

The Sigma^- mean squared charge radius has been measured in the space-like Q^2 range 0.035-0.105 GeV^2/c^2 by elastic scattering of a Sigma^- beam off atomic electrons. The measurement was performed with the SELEX (E781) spectrometer using the Fermilab hyperon beam at a mean energy of 610 GeV/c. We obtain = (0.61 +/- 0.12 (stat.) +/- 0.09 (syst.)) fm^2. The proton and pi^- charge radii were measured as well and are consistent with results of other experiments. Our result agrees with the recently measured strong interaction radius of the Sigma^-.

1 data table match query

Total systematic errors are given.


a_1(1260) dominance in the process e+e- \to 4\pi at energies 1.05--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.


The e+ e- ---> 3(pi+ pi-), 2(pi+ pi- pi0) 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.