HEPData Search

In diffractive photoproduction ofηπ+π−, the two-body substatesηρ0 andA2π are found to contribute significantly to the cross-section forηπ+π− masses below 2.4 GeV. From a spin-parity analysis the branching ratio, ρ′(1600)→ηρ/ρ′(1600)→, is determined to be <0.02 at the 68.3% confidence level. TheA2π component shows an enhancement around 1.7 GeV. The spin-parity analysis indicates a probable contribution to this signal from exclusive photoproduction of theg(1690).

3 data tables match query

Table 1

No description provided.

Table 2

Not corrected for 35% background under the eta --> gamma gamma peak.

Table 3

Not corrected for 35% background under the ETA --> GAMMA GAMMA peak.

MEASUREMENT OF THE REAL TO IMAGINARY RATIO OF THE ANTI-P P FORWARD SCATTERING AMPLITUDES

Ashford, V. ; Sainio, M.E. ; Sakitt, M. ; et al.

Phys.Rev.Lett. 54 (1985) 518-521, 1985.

Inspire Record 216074 DOI 10.17182/hepdata.20329

We have measured the ratio of the real to the imaginary parts of the p¯p forward-scattering amplitude in the incident-momentum range 360 to 650 MeV/c. These results are in good agreement with predictions of the Paris nucleon-antinucleon potential model which include spin-flip effects.

3 data tables match query

Table 1

Table 2

RESULTS OF FITS TO THE FORWARD-SCATTERING DIFFERENTIAL CROSS SECTIONS ASSUMING THE RATIO OF THE SPIN-FLIP TO NON-SPIN-FLIP PARTS OF THE FORWARD AMPLITUDE IS ZERO.

Table 3

RESULTS OF FITS TO THE FORWARD-SCATTERING DIFFERENTIAL CROSS SECTIONS ASSUMING THE RATIO OF THE SPIN-FLIP TO NON-SPIN-FLIP PARTS OF THE FORWARD AMPLITUDE IS PARAMATERISED AS 0.3698-0.1384*PLAB(IN GEV).

Test of {QED} in the Reactions $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \mu^+ \mu^-$ at {CMS} Energies From 9.4-{GeV} to 31.6-{GeV}

The PLUTO collaboration Berger, Christoph ; Genzel, H. ; Grigull, R. ; et al.

Z.Phys.C 4 (1980) 269, 1980.

Inspire Record 152289 DOI 10.17182/hepdata.15600

None

2 data tables match query

Table 1

No description provided.

Table 2

No description provided.

K- p Reactions from 0.96-GeV/c to 1.355-GeV/c Involving Two-Body Final States

The Rutherford-London collaboration Conforto, B. ; Gopal, G.P. ; Kalmus, G.E. ; et al.

Nucl.Phys.B 105 (1976) 189-221, 1976.

Inspire Record 2769 DOI 10.17182/hepdata.8717

Data are presented from a high statistics bubble chamber experiment to study K − p interactions in the c.m. energy range 1775 to 1957 MeV. For the reactions K − p → K − p, K − p → K 0 n , K − p → Λπ 0 and K − p → Σ ± π ∓ channel cross sections, differential cross sections and, where appropriate, polarisation distributions have been obtained. The channel cross sections for K − p → Σ 0 π 0 are presented. In general the results are in agreement with those previously published although a significant discrepancy has been found in the Σ ± π ∓ cross sections at the lower energies. New measurements of the Σ ± lifetimes have also been obtained ( τ Σ − = 1.49 ± 0.03 × 10 −10 sec, τ Σ + = 0.807 ± 0.013 × 10 −10 sec).

3 data tables match query

Table 1

No description provided.

Table 2

THE FORWARD DIFFERENTIAL CROSS SECTION IS THE EXTRAPOLATED VALUE OF THE LEGENDRE POLYNOMIAL FIT.

Table 3

No description provided.

Compton scattering of quasi-real virtual photons at LEP.

The L3 collaboration Achard, P. ; Adriani, O. ; Aguilar-Benitez, M. ; et al.

Phys.Lett.B 616 (2005) 145-158, 2005.

Inspire Record 679959 DOI 10.17182/hepdata.48828

Compton scattering of quasi-real virtual photons, gamma e+- -> gamma e+-, is studied with 0.6fb-1 of data collected by the L3 detector at the LEP e+e- collider at centre-of-mass energies root(s')=189-209GeV. About 4500 events produced by the interaction of virtual photons emitted by e+- of one beam with e-+ of the opposite beam are collected for effective centre-of-mass energies of the photon-electron and photon-positron systems in the range from root(s')= 35GeV up to root(s')=175GeV, the highest energy at which Compton scattering was ever probed. The cross sections of the gamma e+- -> gamma e+- process as a function of root(s') and of the rest-frame scattering angle are measured, combined with previous L3 measurements down to root(s')~20GeV, and found to agree with the QED expectations.

3 data tables match query

Table 1

Measured Compton scattering cross section as a function of the effective centre of mass of the photon-electron system. THETA(RF=CM) is the electron rest frame scattering angle.

Table 2

The measured angular distribution over the photon-electron centre of mass energy range 35 to 175 GeV.

Table 3

The measured Compton scattering cross section using the full data sample including the lower energy data from Acciarri et al. PL B439(1998)183. Errors are combined statistics and systematics.

Test of the four-fermion contact interaction in e+ e- collisions at 130-GeV to 140-GeV.

The OPAL collaboration Alexander, G. ; Allison, John ; Altekamp, N. ; et al.

Phys.Lett.B 387 (1996) 432-442, 1996.

Inspire Record 421997 DOI 10.17182/hepdata.47754

The differential cross-sections for e + e − → e + e − , e + e − → μ + μ − and e + e − → τ + τ − , and the total cross-section for e + e − → qq̄ at centre-of-mass energies of 130–140 GeV were studied using about 5 pb −1 of data collected with the OPAL detector at LEP in October and November 1995. The results are in agreement with the Standard Model predictions. Four-fermion contact interaction models were fitted to the data and lower limits were obtained on the energy scale Λ at the 95% confidence level.

1 data table match query

Table 1

No description provided.

Measurement of hadron and lepton pair production at 130-GeV less than S**(1/2) less than 189-GeV at LEP

The L3 collaboration Acciarri, M. ; Achard, P. ; Adriani, O. ; et al.

Phys.Lett.B 479 (2000) 101-117, 2000.

Inspire Record 513676 DOI 10.17182/hepdata.48958

We report on measurements of e+e- annihilation into hadrons and lepton pairs. The data have been collected with the L3 detector at LEP at centre-of-mass energies between 130 and 189 GeV. Using a total integrated luminosity of 243.7 pb^-1, 25864 hadronic and 8573 lepton-pair events are selected for the measurement of cross sections and leptonic forward-backward asymmetries. The results are in good agreement with Standard Model predictions.

3 data tables match query

Table 4

Measured cross sections for the electron-pair events. For Bhabha scattering events both the leptons have to be inside 44 to 136 degrees.

Table 7

Measured cross sections for the electron-pair events. For Bhabha scattering events both the leptons have to be inside 44 to 136 degrees.

Table 10

Angular distributions for (E+ E-) events for the high energy event sample (ZETA <25 DEGS) Statistical and systematic errors are combined.

Experimental Study of Electroweak Parameters at {PETRA} Energies (12-{GeV} $< E_{CMS} <$ 36.7-{GeV})

The MARK-J collaboration Barber, D.P. ; Becker, U. ; Bei, G.D. ; et al.

Phys.Rev.Lett. 46 (1981) 1663, 1981.

Inspire Record 164675 DOI 10.17182/hepdata.3303

We have performed a high-statistics measurement of Bhabha scattering and of the production of hadrons in electron-positron annihilation at PETRA energies (12 GeV<~s<~36.7 GeV). Combining the results with measurements of μ+μ− and τ+τ− production enables us to compare our results with electroweak theory. We find sin2θw=0.27±0.08. This is in good agreement with the value obtained from neutrino experiments which were carried out in entirely different kinematic regions.

1 data table match query

Table 1

No description provided.

A Test of Universality of Charged Leptons

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.

Phys.Rev.Lett. 43 (1979) 1915, 1979.

Inspire Record 142012 DOI 10.17182/hepdata.20759

Measurements of the reactions e++e−→e++e−, μ++μ−, and τ++τ− at PETRA energies (s12=13,17,27.4,30 and 31.6 GeV) are reported. The results show that these reactions agree well with the predictions of quantum electrodynamics thus determining that all the known charged leptons are pointlike particles to a distance < × 10−16 cm.

1 data table match query

Table 1

No description provided.

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ON STUDY OF PION MULTIPLE PRODUCTION IN NONDIFFRACTIVE EXCLUSIVE REACTIONS IN K- p INTERACTIONS AT 32.1-GeV/c

Study of $\eta \pi^+ \pi^-$ States in the $\rho^\prime$ (1600) Mass Region Photoproduced in the Reaction $\gamma p \to \eta \pi^+ \pi^- p$ at Photon Energies of 20-{GeV} to 70-{GeV}

MEASUREMENT OF THE REAL TO IMAGINARY RATIO OF THE ANTI-P P FORWARD SCATTERING AMPLITUDES

Test of {QED} in the Reactions $e^+ e^- \to e^+ e^-$ and $e^+ e^- \to \mu^+ \mu^-$ at {CMS} Energies From 9.4-{GeV} to 31.6-{GeV}

K- p Reactions from 0.96-GeV/c to 1.355-GeV/c Involving Two-Body Final States

Compton scattering of quasi-real virtual photons at LEP.

Test of the four-fermion contact interaction in e+ e- collisions at 130-GeV to 140-GeV.

Measurement of hadron and lepton pair production at 130-GeV less than S**(1/2) less than 189-GeV at LEP

Experimental Study of Electroweak Parameters at {PETRA} Energies (12-{GeV} $< E_{CMS} <$ 36.7-{GeV})

A Test of Universality of Charged Leptons