Measurement of the electron-positron annihilation cross-section into pi+ pi-, k+ k- pairs at the total energy 1.18-1.34 gev

Balakin, V.E. ; Budker, G.I. ; Kurdadze, L.M. ; et al.
Phys.Lett.B 41 (1972) 205-208, 1972.
Inspire Record 75634 DOI 10.17182/hepdata.28229

Using the electron-position storage ring VEPP-2 an experiment has been performed in which the cross-sections of the reactions e + e − → π + π − and e + e − →K + K − were measured in the energy regi on 1.18–1.34 GeV. The experimental values of the formfactors lie higher than curves extrapolated from the ϱ- and ϕ-meson region.

2 data tables match query

No description provided.

No description provided.


Investigation of the phi-meson resonance by electron-positron colliding beams

Balakin, V.E. ; Budker, G.I. ; Pakhtusova, E.V. ; et al.
Phys.Lett.B 34 (1971) 328-332, 1971.
Inspire Record 69313 DOI 10.17182/hepdata.28704

Using the colliding beam machine, VEPP-2, the excitation curve of the ø-meson resonance was investigated in the three main decay modes. The resonance parameters obtained are the width, the total cross-section and the branching ratios. Namely: Γ = (4.67 ± 0.42) Mev B ( K + K − ) = (54.0 ± 3,4) % σ o = (3.96 ± 0.35) μB B ( K o s K O L ) = (25.7 ±3,0) % B ( e + e − = (2,81 ± 0.25) × 10 −4 B ( π + π − π o ) = (20.3 ± 4,2) %

2 data tables match query

BREIT-WIGNER FITS TO DATA POINTS AT 9 ENERGIES AROUND PHI FOR EACH CHANNEL. PEAK CROSS SECTIONS QUOTED.

PION FORM FACTOR AT PHI MASS, ALLOWING FOR POSSIBLE INTERFERENCE.


Version 2
Investigation of the ϱ-meson resonance with electron-positron colliding beams

Auslander, V.L. ; Budker, G.I. ; Pestov, Ju N. ; et al.
Phys.Lett.B 25 (1967) 433-435, 1967.
Inspire Record 1392895 DOI 10.17182/hepdata.29437

Preliminary results on the determination of the position and shape of the ϱ-meson resonance with electron-positron colliding beams are presented.

2 data tables match query

Measured value of the pion form factor

Fitted peak cross section.


Version 2
Investigation of the rho-meson resonance with electron-positron colliding beams

Auslander, V.L. ; Budker, G.I. ; Pakhtusova, E.V. ; et al.
Yad.Fiz. 9 (1969) 114-119, 1969.
Inspire Record 57008 DOI 10.17182/hepdata.18687

None

2 data tables match query

Measured value of the pion form factor

Fitted peak cross section.


Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Sivers asymmetries

The COMPASS collaboration Adolph, C. ; Alekseev, M.G. ; Alexakhin, V.Yu. ; et al.
Phys.Lett.B 717 (2012) 383-389, 2012.
Inspire Record 1115721 DOI 10.17182/hepdata.59737

The COMPASS Collaboration at CERN has measured the transverse spin azimuthal asymmetry of charged hadrons produced in semi-inclusive deep inelastic scattering using a 160 GeV positive muon beam and a transversely polarised NH_3 target. The Sivers asymmetry of the proton has been extracted in the Bjorken x range 0.003<x<0.7. The new measurements have small statistical and systematic uncertainties of a few percent and confirm with considerably better accuracy the previous COMPASS measurement. The Sivers asymmetry is found to be compatible with zero for negative hadrons and positive for positive hadrons, a clear indication of a spin-orbit coupling of quarks in a transversely polarised proton. As compared to measurements at lower energy, a smaller Sivers asymmetry for positive hadrons is found in the region x > 0.03. The asymmetry is different from zero and positive also in the low x region, where sea-quarks dominate. The kinematic dependence of the asymmetry has also been investigated and results are given for various intervals of hadron and virtual photon fractional energy. In contrast to the case of the Collins asymmetry, the results on the Sivers asymmetry suggest a strong dependence on the four-momentum transfer to the nucleon, in agreement with the most recent calculations.

54 data tables match query

The Sivers asymmetry, from the 2010 data set, for positive hadrons as a function of X for full range. Also shown are the mean values of other variables plus the correlation with the Collins data measurments.

The Sivers asymmetry, from the 2010 data set, for negative hadrons as a function of X for full range. Also shown are the mean values of other variables plus the correlation with the Collins data measurments.

The Sivers asymmetry, from the 2010 data set, for positive hadrons as a function of PT for full range. Also shown are the mean values of other variables plus the correlation with the Collins data measurments.

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Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Collins asymmetries

The COMPASS collaboration Adolph, C. ; Alekseev, M.G. ; Alexakhin, V.Yu. ; et al.
Phys.Lett.B 717 (2012) 376-382, 2012.
Inspire Record 1115720 DOI 10.17182/hepdata.59732

The COMPASS Collaboration at CERN has measured the transverse spin azimuthal asymmetry of charged hadrons produced in semi-inclusive deep inelastic scattering using a 160 GeV positive muon beam and a transversely polarised NH_3 target. The Collins asymmetry of the proton was extracted in the Bjorken x range 0.003<x<0.7. These new measurements confirm with higher accuracy previous measurements from the COMPASS and HERMES collaborations, which exhibit a definite effect in the valence quark region. The asymmetries for negative and positive hadrons are similar in magnitude and opposite in sign. They are compatible with model calculations in which the u-quark transversity is opposite in sign and somewhat larger than the d-quark transversity distribution function. The asymmetry is extracted as a function of Bjorken $x$, the relative hadron energy $z$ and the hadron transverse momentum p_T^h. The high statistics and quality of the data also allow for more detailed investigations of the dependence on the kinematic variables. These studies confirm the leading-twist nature of the Collins asymmetry.

54 data tables match query

The Collins asymmetry, from the 2010 data set, for positive hadrons as a function of X for full range. Also shown are the mean values of other variables plus the correlation with the Sivers data measurments.

The Collins asymmetry, from the 2010 data set, for negative hadrons as a function of X for full range. Also shown are the mean values of other variables plus the correlation with the Sivers data measurments.

The Collins asymmetry, from the 2010 data set, for positive hadrons as a function of PT for full range. Also shown are the mean values of other variables plus the correlation with the Sivers data measurments.

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A Comparison of the Structure Functions F2 of the Proton and the Neutron From Deep Inelastic Muon Scattering at High $Q^2$

The BCDMS collaboration Benvenuti, A.C. ; Bollini, D. ; Bruni, G. ; et al.
Phys.Lett.B 237 (1990) 599-604, 1990.
Inspire Record 285519 DOI 10.17182/hepdata.29734

High statistics data on the structure functions F 2 of the proton and the deutron measured with the same apparatus in deep inelastic muon scattering are used to study the ratio of structure functions of neutron and proton F 2 n / F 2 p and their difference F 2 p - F 2 n . Both measurements are consistent with predictions of the quark-parton model and of QCD.

2 data tables match query

No description provided.

No description provided.


RESONANCE PRODUCTION IN THE REACTION anti-p d ---> p(s) pi+ pi- pi- pi0 AT 0.4-GeV/c TO 0.9-GeV/c ANTI-PROTON MOMENTA

Kasper, P. ; Chapman, G. ; DeRoach, J. ; et al.
Nucl.Phys.B 156 (1979) 207-224, 1979.
Inspire Record 7267 DOI 10.17182/hepdata.34660

Resonance production has been studied in the annihilation process p n aarπ + π - π - π 0 induced by antiprotons in the 0.4 to 0.9 GeV/ c momentum range. We observe strong production of ϱ mesons, together with some f 0 (predominantly in the ϱf 0 channel), ω 0 and A 2 mesons and there is a strong ϱϱ signal. We also observe a broad (~300 MeV/ c 2 ) enhancement at ~1100 MeV/c 2 in the π + π - π - invariant-mass distribution, whereas no such enhancement is seen in the π + π - π 0 channel; we have considered various explanations for this enhancement, including an “A 1 ” effect and interference between amplitudes for conventional resonance production.

1 data table match query

FITTED PERCENTAGE OF EACH RESONANCE CHANNEL. THE AUTHORS ALSO QUOTE VERY SIMILAR RESULTS FOR THREE OTHER FITS WHICH ALLOW FOR THE <A1(1100)- PI0> CHANNEL OR BOSE-EINSTEIN INTERFERENCE.


DIFFRACTIVE DISSOCIATION OF NEUTRONS IN LAMBDA0 K0 ON HYDROGEN AT ABOUT 40-GeV ENERGY

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
JINR-P1-88-51, 1988.
Inspire Record 261900 DOI 10.17182/hepdata.38806

None

4 data tables match query

No description provided.

No description provided.

No description provided.

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Observation of D0 ---> K+ pi- rho0 produced in interactions of 40-GeV - 70-GeV neutrons with hydrogen, carbon and aluminum

The BIS-2 collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
JINR-P1-90-595, 1990.
Inspire Record 305481 DOI 10.17182/hepdata.38714

None

1 data table match query

No description provided.