Date

Study of Electron - Positron Collisions at the Center-of-mass Energies of 27.4-{GeV} and 27.7-{GeV} at {PETRA}

Barber, D.P. ; Becker, U. ; Benda, H. ; et al.
Phys.Rev.Lett. 43 (1979) 901, 1979.
Inspire Record 141542 DOI 10.17182/hepdata.20739

This paper reports on the first results of the study of e+e− collisions at s=27.4 GeV and s=27.7 GeV at PETRA, using the 4π-sr electromagnetic and calorimetric detector MARK-J. We obtain an average R=σ(e+e−→hadrons)σ(e+e−→μ+μ−)=3.8±0.3 (statistical)±0.6 (systematic) and a relative R=1.0±0.2 between the two energies. The R values, the measured thrust distribution, and average spherocity show no evidence for the production of new quark flavors.

2 data tables

THE RELATIVE VALUE OF R BETWEEN THESE TWO ENERGIES IS 1.0 +- 0.2.

THRUST DISTRIBUTION (1/N)*DN/DTHRUST AT 13, 17 AND 27 GEV. THESE DATA ARE RATHER DETECTOR DEPENDENT.


Photoproduction of $\rho^\prime$ (1.2) and $\rho^\prime$ (1.6) in the Final States $\pi^{+} \pi^{-} \pi^{+} \pi^{-}$ and $\pi^{+} \pi^{-} \pi^0 \pi^0$

The LAMP2 Group collaboration Barber, D.P. ; Dainton, J.B. ; Lee, L.C.Y. ; et al.
Z.Phys.C 4 (1980) 169, 1980.
Inspire Record 141585 DOI 10.17182/hepdata.15607

The elastic photoproduction of four pions has been studied at incident photon energies between 2.8 and 4.8 GeV. Production cross-sections are presented and an analysis of the angular decay correlations is also described, indicating a large 1− contribution in both final states, π+ π− π+ π− and π+ π− π0 π0. A quantitative understanding of these and other available 4π photoproduction data in terms of the ρ′(∼1.2GeV) and the ρ′(∼1.6) is presented.

2 data tables

WITH OMEGA/RHO DECAY PARAMETRIZATION.

WITH OMEGA/A1 DECAY PARAMETRIZATION.


Reaction $\pi^- p \to \omega n$ in the 15-{GeV}/$c$ - 40-{GeV}/$c$ Momentum Range

The Serpukhov-CERN collaboration Apel, W.D. ; Augenstein, K.H. ; Krüger, M. ; et al.
Lett.Nuovo Cim. 25 (1979) 493, 1979.
Inspire Record 142561 DOI 10.17182/hepdata.37383

None

7 data tables

DATA OBTAINED IN ASSUMPTION THAT RHO(MM=00,P=3,XYZ=SH)=1-2*RHO(MM=1-1,P=3,XYZ=SH).

INTEGRATED CROSS SECTION, INCLUDING SYSTEMATIC UNCERTAINTY IN ERRORS Axis error includes +- 15/15 contribution (DECAY-BR(BRN=OMEGA --> PI0 GAMMA,BR=0.088 +- 0.005)).

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Total Cross-Section for Hadronic Production by e+ e- Annihilation in the Total Center-Of-Mass Energy Range 1.42-GeV - 3.09-GeV

Bacci, C. ; Baldini Celio, R. ; Battistoni, G. ; et al.
Phys.Lett.B 86 (1979) 234-238, 1979.
Inspire Record 141722 DOI 10.17182/hepdata.27311

We report experimental results on the cross section for the reaction e + e − → hadrons as a function of the total c.m. energy in the range W = 1.42–3.09 GeV. The results, combined with those already existing below the charm threshold, clearly indicate a structure for R ( W ) = α ( e + e − → hadrons)/ α ( e + e − → μ + μ − ) in that energy region.

2 data tables

THE ENERGY RANGES OF THE NEW DATA AND THE PREVIOUS (REVISED) DATA OVERLAP BETWEEN 1.9 AND 2.0 GEV. RADIATIVE CORRECTIONS HAVE BEEN APPLIED TO ALL DATA. THIS CROSS SECTION EXCLUDES TWO-BODY FINAL STATES.

AVERAGE CHARGED AND NEUTRAL MULTIPLICITY. QUOTED ERRORS ARE STATISTICAL ONLY.


Study of the Reaction $e^+ e^- \to p \bar{p}$ in the Total Energy Range 1925-{MeV} - 2180-{MeV}

Delcourt, B. ; Derado, I. ; Bertrand, J.L. ; et al.
Phys.Lett.B 86 (1979) 395-398, 1979.
Inspire Record 141565 DOI 10.17182/hepdata.27308

The e + e − → p p cross section has been measured between 1925 and 2180 MeV. About 50 p p events were detected. The total cross section decreases from 1.31 ± 0.4 nb near 1937 MeV to 0.55 ± 0.2 nb near 2135 MeV. The proton form factors | G E | 2 and | G M | 2 , assumed identical, decrease from 0.15 ± 0.05 to 0.043 ± 0.015. They are an order of magnitude higher than predicted by the well-known dipole fit. The energy range has been scanned in steps of about 2 MeV. No significant structure was found in this p p sample.

1 data table

TOTAL CROSS SECTION ASSUMING ISOTROPIC PRODUCTION. RADIATIVE CORRECTIONS CALCULATED USING PEAKING APPROXIMATION (ABOUT 20 PCT). AUTHORS ALSO QUOTE RESULTS FOR LIMITED (COSMIC RAY FREE) ACCEPTANCE AS A CHECK. FORM FACTOR DERIVED ASSUMING ELECTRIC AND MAGNETIC FORM FACTORS EQUAL IN MAGNITUDE.


Cross-sections and Multiplicity Distributions for $K^+ p$ Interactions at 70-{GeV}/$c$

Barth, M. ; De Clercq, C. ; De Wolf, E. ; et al.
Z.Phys.C 2 (1979) 285, 1979.
Inspire Record 141693 DOI 10.17182/hepdata.2107

Cross sections and charged multiplicity distributions forK+p interactions at 70 GeV/c are presented and compared withK+p data at other energies. Comparisons are also made with available π+p,pp, andK−p data.

2 data tables

No description provided.

No description provided.


Experimental Study of Low $P_t$ Hadron Fragmentation

Cutts, D. ; Dulude, R.S. ; Lanou, R.E., Jr. ; et al.
Phys.Rev.Lett. 43 (1979) 319, 1979.
Inspire Record 141771 DOI 10.17182/hepdata.9274

We present high-statistics results on the reactions a+p→c+X where a and c can be any of π±, K±, p, or p¯. The data were taken at 100 and 175 GeV/c incident momenta using the Fermilab Single-Arm Spectrometer operated over the kinematic range 0.2<x<1.0 and pt<~1.0 GeV/c. Investigating the x dependence of the data, we find agreement with a quark-parton picture, namely the cross sections have a power-law behavior in 1−x independent of pbeam and pt.

75 data tables

No description provided.

No description provided.

No description provided.

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Channel Cross-sections and Two-body Reactions in $K^- p$ Interactions at 32-{GeV}/$c$

The French-Soviet & CERN-Soviet collaborations Givernaud, A. ; Denegri, D. ; Lewin, C. ; et al.
Nucl.Phys.B 160 (1979) 445-466, 1979.
Inspire Record 141995 DOI 10.17182/hepdata.34613

We present a systematic investigation of channel cross sections in K − p interactions at 32 GeV/ c . The energy dependence of these cross sections is discussed. We also investigate a few non-diffractive two-body reactions. The total cross sections of the two reactions K − p → K ∗− (890) p and K − p → K ∗− (1420) p have a markedly different energy behaviour. There is clear evidence for the reaction K − p → K ∗0 (890) N 0 (1688) ; its differnttial cross section exhibits a sharp forward slope of 24 ± 3 GeV −2 .

3 data tables

FROM AK0 P PI- FINAL STATE.

DOUBLE RESONANCE CHANNEL CROSS SECTIONS FROM BREIT-WIGNER FIT CORRECTED FOR BACKGROUND AND DIFFRACTIVE PROCESSES.

No description provided.


Inclusive Production of $D$ and $K$ Mesons in $e^+ e^-$ Annihilation

Piccolo, M. ; Peruzzi, I. ; Rapidis, P.A. ; et al.
Phys.Lett.B 86 (1979) 220-224, 1979.
Inspire Record 141018 DOI 10.17182/hepdata.27301

We present measurements of the cross section for inclusive D and K meson production in e + e − annihilation in the center of mass energy range 3.6 to 5.8 GeV. D production accounts for most of the increase in the total cross section for hadron production in e + e − annihilation at energies above 4 GeV.

3 data tables

No description provided.

No description provided.

No description provided.


The Contribution of $q \bar{q}$ Annihilations to Dimuon Production in $\pi N$ Interactions

Reece, C. ; LeBritton, J. ; McCal, D. ; et al.
Phys.Lett.B 85 (1979) 427-431, 1979.
Inspire Record 7886 DOI 10.17182/hepdata.27323

We present data on dimuon production by 16 GeV π + and π − beams on a Cu target. From the data we evaluate, for π − N collisions, the fraction of dimuon events that originate from the annihilation process q q ̄ → μ + μ − . Using this information the experimentally determined cross section for the process q q ̄ → μ + μ − is observed to be in agreement with the Drell-Yan model over a wide range of incident energies. The observed deviations from exact scaling are of the order predicted by QCD calculations for the Q 2 -dependence of the nucleon and the pion structure function.

2 data tables

CROSS SECTIONS ARE PER COPPER NUCLEUS.

CROSS SECTIONS ARE PER COPPER NUCLEUS.