Amirzadeh, J.
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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
Table 1

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
Table 1

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

Table 2

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


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
Table 1

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


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
Table 1

No description provided.


Experimental Test of the {Drell-Yan} Model in $p W \to \mu^+ \mu^- X$

Smith, S.R. ; Childress, S. ; Mockett, P.M. ; et al.
Phys.Rev.Lett. 46 (1981) 1607, 1981.
Inspire Record 164176 DOI 10.17182/hepdata.20659

We report a high-statistics study of the reaction p+W→μ++μ−+X with use of an intense 400-GeV/c proton beam, a magnetized-iron beam dump, and a wide-acceptance detector. Using data near xF=0, we have extracted the nucleon sea-quark distribution and find it to be a factor 1.6±0.3 larger than that obtained by inelastic charged-current neutrino scattering. We then compare the Drell-Yan prediction with our data including the previously unexplored region of large xF and find excellent agreement for a wide range of μ-pair invariant mass.

6 data tables
Table 1

Dimuon mass mass distribution at XFP=0.1.

Table 2

Dimuon production for varying mass as function of XFP.

Table 3

Dimuon production for varying mass as function of XFP.

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MEASUREMENTS OF LAMBDA0 POLARIZATION PRODUCED BY 40-GeV NEUTRONS ON CARBON NUCLEI IN INCLUSIVE PROCESSES

The Dubna-Berlin-Moscow-Prague-Sofiya-Tbilisi collaboration Aleev, A.N. ; Arefev, V.A. ; Balandin, V.P. ; et al.
JINR-P1-81-165, 1981.
Inspire Record 165431 DOI 10.17182/hepdata.39207

None

1 data table
Table 1

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
Table 1

No description provided.

Table 2

No description provided.

Table 3

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
Table 1

No description provided.

Table 2

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


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
Table 1

No description provided.


SMALL /t/ pi- p CHARGE EXCHANGE SCATTERING AT 40-GeV/c

The Serpukhov-Brussels-Annecy(LAPP) collaboration Binon, F.G. ; Davydov, V.A. ; Donskov, S.V. ; et al.
Z.Phys.C 9 (1981) 109, 1981.
Inspire Record 164809 DOI 10.17182/hepdata.13526

π−p→π0n differential cross-sections have been measured in the region of small 4-momentum transfer at 40 GeV/c incident momentum. The experiment performed at the IHEP 70 GeV accelerator makes use of a hodoscope γ-spectrometer. Thet- dependence of the cross-section points to a dominance of the spin-flip amplitude.

1 data table
Table 1

No description provided.