Nakamura, K.
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The Production of Prompt Positrons at Low Transverse Momentum Increases With the Square of the Associated Charged Multiplicity

The Axial Field Spectrometer collaboration Åkesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 192 (1987) 463-470, 1987.
Inspire Record 244887 DOI 10.17182/hepdata.30156

We have measured the production of prompt positrons in pp collisions at √ s = 63 GeV and y = 0 in the p T interval 0.12< p T <1.0 GeV/c. The results indicate that the production of positrons at low p T (<0.4 GeV/ c ) is proportional to the square of the mean multiplicity in the central region | y | < 1. Such a quadratic dependence is not expected from final-state sources such as hadronic bremsstrahlung or hadronic decays, but is natural in models where low mass electron pairs are produced by interactions of constituents created during the collision.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Nuclear Effects in Deep Inelastic Muon Scattering on Deuterium and Iron Targets

The BCDMS collaboration Benvenuti, A.C. ; Bollini, D. ; Bruni, G. ; et al.
Phys.Lett.B 189 (1987) 483-487, 1987.
Inspire Record 244886 DOI 10.17182/hepdata.30200

New Results are presented on nuclear effects in deep inelastic muon scattering on deuterium and iron targets at large Q 2 . The ratio F Fe 2 (x) F D 2 2 (x) measured in the kinematic range 0.06⩽ x ⩽0.70, 14GeV 2 ⩽ Q 2 ⩽70 GeV 2 is in good agreement with earlier measurements in the region of x > 0.25. At lower x , the structure function ratio exhibits an enhancement of ≈5%.

1 data table
Table 1

Q**2 RANGE FOR EACH X BIN IS AS FOLLOWS: 14 TO 20, 16 TO 30, 18 TO 35, 18 TO 46, 20 TO 106, 23 TO 106, 23 TO 150, 26 TO 200, 26 TO 200, 26 TO 200 GEV**2.


MEASUREMENT OF POLARIZATION PARAMETERS FOR THE PI- P ---> PI0 N CHARGE EXCHANGE SCATTERING FROM 1965-MEV/C TO 4220-MEV/C

Minowa, M. ; Adachi, T. ; Daigo, M. ; et al.
Nucl.Phys.B 294 (1987) 979-1000, 1987.
Inspire Record 255228 DOI 10.17182/hepdata.33402

Polarization parameters for the π − p → π 0 n charge exchange scattering have been measured at eight beam momenta between 1965 and 4220 MeV/ c using two different experimental set-ups. The angular range covered is −0.90 < cos θ π ∗ < 0.95 at the five momenta of 1965, 2168, 2360, 2566 and 2960 MeV/ c , where θ π ∗ is the emission angle of the π 0 meson in the c.m.s.. For three momenta of 2770, 3490 and 4220 MeV/ c , the measurements cover the forward angles of 0.1 < cos θ π ∗ < 1.0 . The results are compared with the predictions of π N partial wave analyses.

4 data tables
Table 1

Polarisation measurements from SETUP1. Errors are statistical only.

Table 2

Polarisation measurements from SETUP2. Errors are statistical only.

Table 3

Legendre polynomial coefficients for fit to differential cross section data.

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MEASUREMENT OF DIFFERENTIAL CROSS-SECTIONS FOR THE PI- P ---> PI0 N CHARGE EXCHANGE SCATTERING FROM 1969-MEV/C TO 2965-MEV/C

Suzuki, Y. ; Adachi, T. ; Daigo, M. ; et al.
Nucl.Phys.B 294 (1987) 961-978, 1987.
Inspire Record 255227 DOI 10.17182/hepdata.33477

Precise measurements of the differential cross sections on the π − p→ π 0 n charge exchange scattering have been performed at six incident beam momenta of 1969, 2172, 2370, 2569, 2767 and 2965 MeV/ c covering a wide angular range of −0.95 < cos θ π ∗ < 0.95, where θ π ∗ is an emission angle of π 0 meson in the c.m.s. The results are compared with predictions of recent partial wave analyses.

2 data tables
Table 1

Total cross sections obtained by fitting the Legendre polynomials to the DCS data.

Table 2

Statistical errors only. Cos(theta) bin width is +- 0.025.


Multiplicity, Momentum and Angular Distributions of Protons From the Interactions of $P$, $D$, $\alpha$ and C With Carbon at 4.2-{GeV}/c/nucleon Momentum. Alma-ata-baku-belgrade-bucharest-cracow-dubna-kishinev-leipzig- Moscow-prague-samarkand-sofia-tashkent-tbili

Armutliiski, D. ; Bogdanovic, J. ; Didenko, L.A. ; et al.
Z.Phys.A 328 (1987) 455-461, 1987.
Inspire Record 255393 DOI 10.17182/hepdata.9501

None

17 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Single Diffraction Dissociation in $\pi^+ p$ and $K^+ p$ Interactions at 250-{GeV}/$c$

The EHS/NA22 collaboration Adamus, M. ; Azhinenko, I.V. ; Almeida, F.M.L., Jr. ; et al.
Z.Phys.C 39 (1988) 301, 1988.
Inspire Record 254506 DOI 10.17182/hepdata.15646

None

1 data table
Table 1

No description provided.


Measurement of the Weak Neutral Current Coupling Constants of the Electron and Limits on the Electromagnetic Properties of the Muon Neutrino

Abe, K. ; Ahrens, L.A. ; Amako, K. ; et al.
Phys.Rev.Lett. 58 (1987) 636-639, 1987.
Inspire Record 246621 DOI 10.17182/hepdata.20185

The weak coupling constants of the electron, gVe and gAe, are determined from measurements of the total and differential cross sections for the reaction νμe→νμe. The data also place limits of interest on the magnitudes of a neutrino charge radius and a possible neutrino magnetic dipole moment.

1 data table
Table 1

Neutrino beam 0 - 5 GeV.


Analysis of Transverse Momentum Distributions for $p p$ Interactions at 360-{GeV}/$c$ in the Framework of a Quark - Diquark Fragmentation Model

The EHS-RCBC collaboration Bailly, J.L. ; Bruyant, F. ; Buschbeck, B. ; et al.
Z.Phys.C 35 (1987) 295, 1987.
Inspire Record 245106 DOI 10.17182/hepdata.15802

Using a quark-diquark fragmentation model, in which either the Field-Feynman or the Lund model is coupled with a quark-diquark distribution function, we study transverse momentum distributions,pT, for the inclusive reactionspp→hadron +anything at 360 GeV/c. We find that a primordial mean transverse momentum 〈kT〉≃0.4 GeV/c can well reproduce thepT2 distributions of charged hadrons, π0,Ks0, Λ0,K* and Σ* and the Feynmanx−pT correlations. We confirm that a diquark in a proton plays an important rôle in reproducing thex−pT correlation of Λ0.

1 data table
Table 1

No description provided.


Measurement of the Structure Functions F2 and Xf3 and Comparison With {QCD} Predictions Including Kinematical and Dynamical Higher Twist Effects

The BEBC WA59 collaboration Varvell, K. ; Cooper-Sarkar, A.M. ; Parker, M.A. ; et al.
Z.Phys.C 36 (1987) 1, 1987.
Inspire Record 245094 DOI 10.17182/hepdata.15775

The isoscalar nucleon structure functionsF2(x, Q2) andxF3(x, Q2) are measured in the range 0

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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rivet Analysis
Observation of $e^+ e^- \to D(s$)+- $D^*(s$)-+ at $\sqrt{s}=4$.14-{GeV}

The MARK-III collaboration Blaylock, G. ; Bolton, T. ; Brown, J.S. ; et al.
Phys.Rev.Lett. 58 (1987) 2171, 1987.
Inspire Record 244856 DOI 10.17182/hepdata.20170

We present evidence for the exclusive reaction e+e−→Ds±Ds*∓, observed with the Mark III detector at the SLAC storage ring SPEAR. The Ds± is reconstructed in the φπ± decay mode, while the Ds*∓ is detected as a narrow peak in the recoil-mass distribution. The mass of the Ds* is found to be 2109.3±2.1±3.1 MeV/c2, yielding a Ds*−Ds mass difference of 137.9±2.1±4.3 MeV/c2. The width of the Ds* is <22 MeV/c2 at the 90%-confidence level. The observed signal corresponds to σ(e+e−→Ds+Ds*−+Ds−Ds*+)B(Ds+→φπ+)=30±6±11 pb at s=4.14 GeV.

1 data table
Table 1

No description provided.