Date

Single photoproduction of neutral π-mesons on hydrogen at small angles between 1.3 and 3 GeV

Braunschweig, M. ; Husmann, D. ; Lübelsmeyer, K. ; et al.
Phys.Lett. 22 (1966) 705-708, 1966.
Inspire Record 1389452 DOI 10.17182/hepdata.753

The differential cross section of the reaction γ + p → p + πo has been measured at the Deutsches Elektronen- Synchrotron, Hamburg, at mean phonon energies of 1.36, 2.0 and 3.0 GeV and pion center of mass angles between 0o and 70o. The results are compared with some theoretical calculations based on elementary and reggeized 1- meson exchange.

4 data tables match query

Axis error includes +- 12/12 contribution.

Axis error includes +- 12/12 contribution.

Axis error includes +- 12/12 contribution.

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Single photoproduction of neutral $\pi$-mesons on hydrogen at small angles between 4 and 5.8 GeV

Braunschweig, M. ; Braunschweig, W. ; Husmann, D. ; et al.
Phys.Lett.B 26 (1968) 405-409, 1968.
Inspire Record 1389637 DOI 10.17182/hepdata.29336

The differential cross-section of the reaction γ + p → p + π 0 was measured at the Deutsches Elektronen-Synchrotron, Hamburg, at mean photon energies of 4.0, 5.0 and 5.8 GeV and pion center of mass angles between 0° and 60°. The results are compared wiht theoretical calculations based on Reggeized vector meson exchange.

6 data tables match query

Axis error includes +- 7/7 contribution.

Axis error includes +- 7/7 contribution.

Axis error includes +- 7/7 contribution.

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Spin observables in neutron proton elastic scattering.

Ahmidouch, A. ; Arnold, J. ; van den Brandt, B. ; et al.
Eur.Phys.J.C 2 (1998) 627-641, 1998.
Inspire Record 471273 DOI 10.17182/hepdata.11376

The analyzing power,$A_{oono}$, and the polarization transfer observables$K_{onno}$,$K_{os''so}$

20 data tables match query

Position 'A' (see text for explanation).

Position 'A' (see text for explanation).

Position 'A' (see text for explanation).

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QCD analyses and determinations of alpha(s) in e+ e- annihilation at energies between 35-GeV and 189-GeV.

The JADE & OPAL collaborations Pfeifenschneider, P. ; Biebel, O. ; Movilla Fernandez, P.A. ; et al.
Eur.Phys.J.C 17 (2000) 19-51, 2000.
Inspire Record 513337 DOI 10.17182/hepdata.12882

We employ data taken by the JADE and OPAL experiments for an integrated QCD study in hadronic e+e- annihilations at c.m.s. energies ranging from 35 GeV through 189 GeV. The study is based on jet-multiplicity related observables. The observables are obtained to high jet resolution scales with the JADE, Durham, Cambridge and cone jet finders, and compared with the predictions of various QCD and Monte Carlo models. The strong coupling strength, alpha_s, is determined at each energy by fits of O(alpha_s^2) calculations, as well as matched O(alpha_s^2) and NLLA predictions, to the data. Matching schemes are compared, and the dependence of the results on the choice of the renormalization scale is investigated. The combination of the results using matched predictions gives alpha_s(MZ)=0.1187+{0.0034}-{0.0019}. The strong coupling is also obtained, at lower precision, from O(alpha_s^2) fits of the c.m.s. energy evolution of some of the observables. A qualitative comparison is made between the data and a recent MLLA prediction for mean jet multiplicities.

80 data tables match query

Overall result for ALPHAS at the Z0 mass from the combination of the ln R-matching results from the observables evolved using a three-loop running expression. The errors shown are total errors and contain all the statistics and systematics.

Weighted mean for ALPHAS at the Z0 mass determined from the energy evolutions of the mean values of the 2-jet cross sections obtained with the JADE and DURHAMschemes and the 3-jet fraction for the JADE, DURHAM and CAMBRIDGE schemes evaluted at a fixed YCUT.. The errors shown are total errors and contain all the statistics and systematics.

Combined results for ALPHA_S from fits of matched predicitions. The first systematic (DSYS) error is the experimental systematic, the second DSYS error isthe hadronization systematic and the third is the QCD scale error. The values of ALPHAS evolved to the Z0 mass using a three-loop evolution are also given.

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Target asymmetry for neutral pi meson photoproduction on polarized protons at 4 GeV in the forward direction

Bienlein, H. ; Braunschweig, W. ; Dinter, H. ; et al.
Phys.Lett.B 46 (1973) 131-134, 1973.
Inspire Record 84690 DOI 10.17182/hepdata.28065

The asymmetry A = (σ + −σ − ) (σ + +σ − ) of the reaction γ p↑↓ → π 0 p was measured at the Deutsches Elektronen Synchrotron DESY, Hamburg at a mean photon energy of 4.0 GeV in the four-momentum transfer range 0.2 (GeV/ c ) 2 ⩽ −t ⩽ 1.1 (GeV/ c ) 2 in steps of approximately 0.08 (GeV/ c ) 2 . The π 0 -meson and the proton were detected in coincidence. The asymmetry is compatible with zero in the t -range 0.2 (GeV/ c ) 2 ⩽ − t ⩽ 0.4 (GeV/ c ) 2 and negative in the t -range ⩾ 0.5 (GeV/ c ) 2 .

1 data table match query

No description provided.


Single photoproduction of neutral pi mesons on deuterium in the forward direction at 4 gev

Braunschweig, W. ; Dinter, H. ; Erlewein, W. ; et al.
Nucl.Phys.B 51 (1973) 157-166, 1973.
Inspire Record 84302 DOI 10.17182/hepdata.32703

The ratio R = (d σ /d t )( γ d → ( π 0 n)p)/(d σ /d t )( γ d → ( π 0 p)n), was measured at the Deutsches Elektronen-Synchrotron DESY, Hamburg at a mean photon energy of 4.0 GeV in the four-momentum transfer range between t = − 0.2 (GeV/ c ) 2 and t = − 1.2 (GeV/ c ) 2 in steps of approximately 0.08 (GeV/ c ) 2 . The ratio R is less than 1 up to t = − 0.9 (GeV/ c ) 2 and shows a broad minimum around t = − 0.6 (GeV/ c ) 2 . Corrections for nuclear effects in the deuterium were not applied but are shown to be small.

1 data table match query

No description provided.


Single photoproduction of neutral pi mesons on hydrogen in the forward direction at 4 gev

Braunschweig, W. ; Erlewein, W. ; Frese, H. ; et al.
Nucl.Phys.B 51 (1973) 167-173, 1973.
Inspire Record 84301 DOI 10.17182/hepdata.32708

The differential cross section of the reaction γ p → π 0 p has been measured at the Deutsches Elektronen Synchrotron DESY, Hamburg, at a mean photon energy of 4.0 GeV in the four-momentum transfer range between t = −0.2 (GeV/ c ) 2 and t = −1,2 (GeV/ c ) 2 in steps of approximately 0.08 (GeV/ c ) 2 . The experiment was carried out in connection with the measurements of the photoproduction of π 0 mesons on deuterium, which were described in the preceding article. In the present paper the contributions arising from background reactions are discussed in more detail.

1 data table match query

No description provided.


Single photoproduction of eta-mesons on hydrogen in the forward direction at 4 and 6 gev

Braunschweig, W. ; Erlewein, W. ; Frese, H. ; et al.
Phys.Lett.B 33 (1970) 236-240, 1970.
Inspire Record 63065 DOI 10.17182/hepdata.28543

The differential cross-section of the reaction γ p→ η p has been measured at the Deutsches Elektronen Synchrotron (DESY) at mean photon energies of 4 and 6 GeV in the momentum transfer range between zero and 1.4 GeV 2 . The data show a slight maximum around t =−0.15 GeV 2 and fall off smoothly till t =−1.4 GeV 2 . There is no indication of a dip around t =−0.5 GeV 2 .

2 data tables match query

Axis error includes +- 19/19 contribution.

Axis error includes +- 19/19 contribution.


Photoproduction of neutral pions on hydrogen at photon energies between 200 and 440 mev

Fischer, G. ; Fischer, H. ; Von Holtey, G. ; et al.
Nucl.Phys.B 16 (1970) 93-101, 1970.
Inspire Record 62733 DOI 10.17182/hepdata.16659

Differential cross sections for neutral-pion photoproduction on hydrogen in the region of the first resonance have been measured by two independent experiments detecting the recoil protons. The results of both measurements have been combined into one set of cross sections covering the photon energy range from 200 to 440 MeV at pion c.m. angles between 50 and 160 degrees.

55 data tables match query

No description provided.

No description provided.

No description provided.

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Spin observables in elastic proton scattering from polarized He-3

Brash, E.J. ; Hausser, O. ; Cummings, W.J. ; et al.
Phys.Rev.C 52 (1995) 807-817, 1995.
Inspire Record 411136 DOI 10.17182/hepdata.25873

We have measured the absolute cross section σ(θ) and complete sets of spin observables A00ij in He3(p,p) elastic scattering at energies of 200 and 500 MeV. The observables depend on linear combinations of six complex scattering amplitudes for the p−3He system and provide a severe test of current reaction models. The in-scattering plane observables (A00mm, A00ll, A00lm, and A00ml) are all in quantitative disagreement with fully microscopic nonrelativistic optical model calculations and nonrelativistic distorted wave Born approximation calculations.

6 data tables match query

A00N0 is analyzing power.

A00N0 is analyzing power.

A00NN is spin correlation parameter.

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