Gopal, G.P.
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First Measurement of the Reaction $\pi^- e \to \pi^- \pi^0 e$

Amendolia, S.R. ; Arik, M. ; Badelek, B. ; et al.
Phys.Lett.B 155 (1985) 457-460, 1985.
Inspire Record 213172 DOI 10.17182/hepdata.30413

The first observation of neutral pion production in π e inelastic scattering is presented. The cross section at 300 GeV for | t ‖>62;10 −3 (GeV / c ) 2 is 2.11 ± 0.47 nb, in good agreement with the theory of PCAC anomalies with 3 quark colours.

1 data table
Table 1

No description provided.


ANGULAR AND ENERGY DEPENDENCE OF THE CROSS-SECTION AND ANALYZING POWER OF THE REACTION P P ----> D PI+ BETWEEN 725-MEV AND 1000-MEV

Mayer, B. ; Bertini, R. ; Cameron, J.M. ; et al.
Nucl.Phys.A 437 (1985) 630-642, 1985.
Inspire Record 217258 DOI 10.17182/hepdata.37040

The differential cross section and analyzing power of the reaction pp → d π + were measured for nine incident proton energies between 725 and 1000 MeV. A magnetic spectrometer was used to detect either deuterons or pions. Cross-section and analyzing-power angular distributions were respectively fitted with Legendre polynomial and associated Legendre function expansions, the coefficients of which were found to vary smoothly with energy in the vicinity of the alleged 3 F 3 dibaryon resonance.

12 data tables
Table 1

Data present here in form of Legendre polynomial fit.

Table 2

Legendre Polynomial fit to cross section.

Table 3

Legendre polynomial fit to analysing power.

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A Measurement of $\bar{p} p$ and $p p$ Elastic Scattering in the Dip Region at $\sqrt{s}=53$-{GeV}

Breakstone, A. ; Crawley, H.B. ; Dallavalle, G.M. ; et al.
Phys.Rev.Lett. 54 (1985) 2180, 1985.
Inspire Record 212895 DOI 10.17182/hepdata.20368

We have measured the differential cross section for p¯p and pp elastic scattering at s=53 GeV in the interval 0.5<|t|<4.0 (GeV/c)2 at the CERN intersecting storage rings using the split-field magnet detector. The shape of the differential cross section differs significantly between p¯p and pp scattering in the region 1.1<|t|<1.5 (GeV/c)2, with p¯p data showing a less pronounced dip structure than pp data.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


TRANSVERSE SPIN DEPENDENCE OF THE P P TOTAL CROSS-SECTION DELTA sigma-t FROM 0.8-GEV/C TO 2.5-GEV/C

Madigan, W.P. ; Bell, D.A. ; Buchanan, J.A. ; et al.
Phys.Rev.D 31 (1985) 966-975, 1985.
Inspire Record 216906 DOI 10.17182/hepdata.23564

The difference ΔσT=σ(↓↑)-σ(↑↑) between the proton-proton total cross sections for protons in pure transverse-spin states, was measured at incident momenta 0.8 to 2.5 GeV/c in experiments performed at the Los Alamos Clinton P. Anderson Meson Physics Facility and the Argonne Zero Gradient Synchrotron. In agreement with other data, peaks were observed at center-of-mass energies of 2.14 and 2.43 GeV/c2, where D21 and G41 dibaryon resonances have been proposed.

2 data tables
Table 1

DATA FROM LAMPF EXPERIMENT.

Table 2

DATA FROM ARGONNE EXPERIMENT.


Electroweak Effects in $e^+ e^- \to \tau^+ \tau^-$ at 29-{GeV}

Fernandez, E. ; Ford, William T. ; Qi, N. ; et al.
Phys.Rev.Lett. 54 (1985) 1620, 1985.
Inspire Record 207555 DOI 10.17182/hepdata.3267

A high-statistics measurement is presented of the cross section for the process e+e−→τ+τ− at s=29 GeV from the MAC detector at PEP. A fit to the angular distribution of our sample of 10 153 events with |cosθ|<0.9 gives an asymmetry Aττ=−0.055±0.012±0.005 from which we find the product of electron and tau axial-vector weak neutral couplings gAegAτ=0.22±0.05.

4 data tables
Table 1

Data fully corrected up to O(ALPHA**3) radiative effects. Data requested from authors.

Table 2

Data extrapolated to full acceptance.

Table 3

No description provided.

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rivet Analysis
Precision Measurement of the Total Cross-section for $e^+ e^- \to$ Hadrons at a Center-of-mass Energy of 29-{GeV}

Fernandez, E. ; Ford, William T. ; Qi, N. ; et al.
Phys.Rev.D 31 (1985) 1537, 1985.
Inspire Record 206052 DOI 10.17182/hepdata.4048

We report a high-precision measurement of the ratio R of the total cross section for e+e−→hadrons to that for e+e−→μ+μ−, at a center-of-mass energy of 29.0 GeV using the MAC detector. The result is R=3.96±0.09. This value of R is used to determine a value of the strong coupling constant αs of 0.23±0.06, nearly independent of fragmentation models. Two different analysis methods having quite different event-selection criteria have been used and the results are in agreement. Particular attention has been given to the study of systematic errors. New higher-order QED calculations are used for the luminosity determination and the acceptance for hadrons.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Test of S Channel Helicity Conservation in Inelastic $\rho^0$ Diffraction in 20-{GeV} Photoproduction

The SLAC Hybrid Facility Photon collaboration Abe, K. ; Bacon, T.C. ; Ballam, Joseph ; et al.
Phys.Rev.D 32 (1985) 2288, 1985.
Inspire Record 209692 DOI 10.17182/hepdata.23546

The reaction γp→ρfast0pπ+π− has been studied with the linearly polarized 20-GeV monochromatic photon beam at the SLAC Hybrid Facility to test the prediction of s-channel helicity conservation in inelastic diffraction for t’<0.4 (GeV/c)2. In a sample of 1934 events from this reaction, the ρ0 decay-angular distributions and spin-density-matrix elements are consistent with s-channel helicity conservation, the π+π− mass shape displays the same skewing as seen in the reaction γp→pπ+π−, and the pπ+π− mass distribution compares well and scales according to the vector dominance model with that produced in π±p→πfast±pπ+π−.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

SPIN DENSITY MATRIX ELEMENTS FOR THE DIFFRACTIVE RHO0 MESON FROM STUDY OF THE ANGULAR DISTRIBUTIONS. CORRECTION HAS BEEN MADE FOR THE (20 +- 5) PCT NON DIFFRACTIVE BACKGROUND IN THE FINAL DATA SAMPLE, ASSUMING IT TO HAVE AN ISOTOPIC ANGULAR DISTRIBUTION.


DIFFERENTIAL CROSS-SECTION OF THE pi+ p ---> K+ SIGMA+ (1385) REACTION AT 12-GeV/c

The Dubna-Serpukhov-Baku-Bratislava-Kosice-Minsk-Samarkand-Tbilisi collaboration Bitsadze, G.S. ; Budagov, Yu.A. ; Vinogradov, V.B. ; et al.
JINR-P1-84-658, 1984.
Inspire Record 207769 DOI 10.17182/hepdata.9877

None

7 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (?////NOT GIVEN).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////NOT GIVEN).

Table 3

No description provided.

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EXPERIMENTAL STUDY OF THE pi+ p ---> K+ SIGMA+ REACTION AT 12-GeV/c

The Dubna-Serpukhov-Baku-Bratislava-Gomel-Yerevan-Kiev-Kosice- Minsk-Samarkand-Tbilisi collaboration Bitsadze, G.S. ; Budagov, Yu.A. ; Vinogradov, V.B. ; et al.
Nucl.Phys.B 260 (1985) 497-509, 1985.
Inspire Record 207765 DOI 10.17182/hepdata.33721

The results of the study of the π + p→K + ∑ + (1) and π + p→K + ∑ + (1385) (2) reactions at 12 GeV/ c are presented. The differential cross sections d σ /d t in| t min |<| t |<0.8 (GeV/ c ) 2 momentum transfer range are measured. The ∑ + polarisation for | t |<0.5 (GeV/ c ) 2 for reaction (1) is defined. Binary reactions (1) and (2) were selected by analyzing the missing mass spectra for the forward emitted fast K + meson. The total cross sections in the studied momentum transfer range are 20.2±2.4 μ b and 7.3±1.1 μ b for the reactions (1) and (2) respectively. The experimental results are compared with the predictions of the Regge models which take into account rescattering and secondary singularities.

4 data tables
Table 1

SYSTEMATIC ERRORS INCLUDED.

Table 2

No description provided.

Table 3

No description provided.

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BEHAVIOR OF pi- MESON PRODUCTION INVARIANT DIFFERENTIAL CROSS-SECTIONS IN NUCLEAR INTERACTIONS AT 4.2-GeV/c PER NUCLEON

Armutliisky, D. ; Gasparian, A.P. ; Grishin, V.G. ; et al.
Yad.Fiz. 42 (1985) 200-204, 1985.
Inspire Record 207766 DOI 10.17182/hepdata.17537

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.