Date

Observation of a Dip at /T/ = 1.5-({GeV}/$c$)**2 in $\bar{p} p$ Elastic Scattering at 50-{GeV}/$c$

The Annecy(LAPP)-CERN-Bohr Inst-Genoa-Oslo-London collaboration Asad, Z. ; Baglin, C. ; Benso, S. ; et al.
Phys.Lett.B 108 (1982) 51, 1982.
Inspire Record 164883 DOI 10.17182/hepdata.31019

The p p elastic differential cross section at 50 GeV/c has been measured in a two-arm spectrometer experiment at the CERN SPS. The | t | range covered extends from 0.7 to 5 (GeV/c. A pronounced dip-bump structure is observed with a sharp minimum at | t | = 1.5 (GeV/ c ) 2 .

1 data table

No description provided.


Measurement of the Ratio of Total and Differential Cross-sections on Neutron and Proton for Charged Current Neutrino Events

The BEBC TST Neutrino collaboration Armenise, N. ; Calicchio, M. ; Erriquez, O. ; et al.
Phys.Lett.B 102 (1981) 374-380, 1981.
Inspire Record 164906 DOI 10.17182/hepdata.31183

Charged-current neutrino interactions have been analysed in a sample of pictures from BEBC equipped with a TST. Using a method independent of both the neutrino flux and nuclear interaction corrections, the ratio R = σ n / σ p has been measured. The result is R =1.98±0.19 for the ratio of total cross sections. Bjorken x distributions for proton and neutron targets and for u and d quarks are compared.

3 data tables

No description provided.

No description provided.

No description provided.


A Determination of Quark Weak Couplings at {PETRA} Energies

The JADE collaboration Bartel, W. ; Cords, D. ; Dittmann, P. ; et al.
Phys.Lett.B 101 (1981) 361, 1981.
Inspire Record 164812 DOI 10.17182/hepdata.31227

Data on hadron production by e + e − annihilation at c.m. energies between 12 and 36.6 GeV have been collected using the JADE detector. They have been analysed in terms of single-photon and weak neutral-current exchange assuming production of quark-antiquark pairs with only d, u, s, c and b quarks to produce values for the quark weak neutral-current couplings. A further analysis in terms of the Glashow-Salam-Weinberg theory produced the result, sin 2 θ W = 0.22 ± 0.08 . The theory has therefore been tested in a new energy domain and within the context of the neutral weak couplings of the first, second and third generation quarks.

2 data tables

No description provided.

WIDTH(Z) = 2.5 GEV WAS ASSUMED. CONST(N=SIN2TW) WAS DETERMINED FROM RATIO(HADRONS/MU). FIRST ORDER QCD.


The Reaction $\gamma p \to p \pi^+ \pi^- \pi^+ \pi^-$ for Photon Energies From 25-{GeV} to 70-{GeV}

The Bonn-CERN-Ecole Poly-Glasgow-Lancaster-Manchester-Orsay-Paris-Rutherford-Sheffield collaboration Aston, D. ; Atkinson, M. ; Bailey, R. ; et al.
Nucl.Phys.B 189 (1981) 15-39, 1981.
Inspire Record 164533 DOI 10.17182/hepdata.34258

Measurements of the reaction γ p → p π + π − π + π − are presented, in which π + π − π + π − systems with masses up to 3 GeV are produced from fragmentation of the incident photon. The reaction is dominated by production of the large peak of the ϱ′(1600) meson and, at higher masses ≳2 GeV, y production of jet-like 4 π systems. The ϱ′(1600) meson is produced by a predominantly s -channel helicity conserving mechanism. At higher masses there are also indications of ϱπ peaks, of masses 1.3 GeV (the A 2 meson) and 1.75 GeV, produced with a recoiling π meson by a mechanism consistent with the Deck effect.

1 data table

CORRECTED FOR TAILS OF BREIT-WIGNER RESONANCE USED IN FIT AND ALLOWING FOR 10 PCT BACKGROUND.


A Measurement of the Cross-Section for Four Pion Production in gamma gamma Collisions at SPEAR

Burke, D.L. ; Abrams, G.S. ; Alam, M.S. ; et al.
Phys.Lett.B 103 (1981) 153-156, 1981.
Inspire Record 165016 DOI 10.17182/hepdata.31168

We present a measurement of the cross section for the reaction e + e − → e + e − π + π − π + π − at SPEAR. This channel is found to be large and dominated by the process γγ → ϱ 0 ϱ 0 → π + π − π + π − . The cross section, which is small just above the four-pion threshold, exhibits a large enhancement near the ϱ 0 ϱ 0 threshold.

1 data table

Axis error includes +- 0.0/0.0 contribution (THE QUOTED ERRORS INCLUDE VARIOUS SYSTEMATIC ERRORS ADDED QUADRATICALLY).


Evidence for Planar Events and a Forward Double Jet Structure in Deep Inelastic Muon Scattering

The European Muon collaboration Aubert, J.J. ; Bassompierre, G. ; Becks, K.H. ; et al.
Phys.Lett.B 100 (1981) 433-438, 1981.
Inspire Record 164536 DOI 10.17182/hepdata.31213

The final states of charged hadrons produced in 280 GeV μp scattering are analysed with respect to their planarity and jet structure. Distributions of p ⊥ 2 in and p ⊥ out 2 are presented. A two jet structure in the forward hemisphere is observed for events with high p ⊥ tracks are predicted by QCD models.

2 data tables

PTIN**2 is the sum of the PTIN components squared.

PTOUT**2 is the sum of the PTOUT components squared.


Measurement of $D^*$ Production in Pion - Nucleon Interactions at 200-{GeV}/$c$

Fitch, V.L. ; Montag, A.D. ; Sherman, S.S. ; et al.
Phys.Rev.Lett. 46 (1981) 761, 1981.
Inspire Record 10286 DOI 10.17182/hepdata.20641

Results are reported of an experiment to measure the cross section for production of the D*+ (D*−) in 200-GeV/c π−N interactions. We observe 78 ± 26 events corresponding to a D*-production cross section dσdy=1.6±0.5 μb at y=0.

1 data table

No description provided.


Production of Vector and Tensor Mesons in Proton Proton Collisions at $\sqrt{s}=52$.5-{GeV}

The Annecy(LAPP)-CERN-College de France-Dortmund-Heidelberg-Warsaw collaboration Drijard, D. ; Fischer, H.G. ; Geist, Walter M. ; et al.
Z.Phys.C 9 (1981) 293, 1981.
Inspire Record 164535 DOI 10.17182/hepdata.14085

Inclusive production of ϱ0,f, andg0 mesons and ofKs0,K*0 (892), ϕ andK*0(1430)mesons has been measured at ∼2.6 and ∼1.1 GeV/c in proton-proton interactions at\(\sqrt s= 52.5\) GeV. The negative particle from the two-body decays of these resonances were identified by a threshold Cerenkov counter and used for triggering. Starting from the measured differential cross section, total inclusive cross sections for the vector and tensor mesons were determined using various parametrizations for they andpT dependence of the differential cross section. The experimental results are discussed in the framework of production models based on the parton picture. The strangeness suppresion factor λ=(0.30±0.10) due toSU(3) symmetry breaking of the quark sea is derived.

1 data table

No description provided.


Inclusive Particle Production in $\pi^- N$ Interactions at High-energies

Abramowicz, H. ; Doroba, K. ; Kossakowski, R. ; et al.
Z.Phys.C 7 (1981) 199-208, 1981.
Inspire Record 166695 DOI 10.17182/hepdata.14106

Results on inclusive particle production in π−n interactions at 21, 205 and 360 GeV/c are presented. The invariant cross sections in both neutron fragmentation and central regions are found to be equal within errors to the corresponding cross sections for π−p collisions and exhibit the same energy dependence. A strong energy dependence of the invariant cross section ratios of negative and positive pions is observed. There is also an indication of transverse momentum dependence of these ratios. The η− correlations in the neutron fragmentation region show little variation with energy and are in agreement with the predictions of the naive quark recombination scheme.

1 data table

DATA ON MULTIPLICITY ARE OBTAINED BY AVERAGING OVER ALL THE TOPOLOGIES EXCEPT THE ONE-PRONG ONE.


Charged Pion Production in 70-{GeV}/$c K^+ P$ Interactions

Barth, M. ; De Clercq, C. ; De Wolf, E.A. ; et al.
Z.Phys.C 7 (1981) 187-198, 1981.
Inspire Record 166694 DOI 10.17182/hepdata.14086

Inclusive charged pion production is studied in an exposure of BEBC, filled with hydrogen, to an incidentK+ beam of 70 GeV/c. Total cross sections for pion production and inclusive longitudinal and transverse momentum distributions of π−'s and of positive particles are presented and compared with data at lower energies. Earlier evidence for scaling in the fragmentation regions is confirmed. The central region π− cross section increases proportionally topLAB−1/4; positive particles show almost no energy dependence atx=0. Particle ratios π+/π− are studied as a function ofx andy* and a comparison with 70 GeV/cK−p data is made. Analysis of structure functions for (ππ) pairs and of particle production associated with π± triggers at large |x| in the context of quark/parton models, provides qualitative evidence for the diquark-quark structure of the proton.

2 data tables

No description provided.

No description provided.