Johnson, W.
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Search for Monochromatic Pion Emission in $\bar{p} p$ Annihilation From Atomic $p$ States

The ASTERIX collaboration Ahmad, S. ; Amsler, Claude ; Armenteros, R. ; et al.
Phys.Lett.B 152 (1985) 135-139, 1985.
Inspire Record 207457 DOI 10.17182/hepdata.49644

Narrow states observable through the emission of monoenergetic charged pions have been searched for in p p annihilation at rest in a gaseous hydrogen target where annihilation from atomic angular momentum L = 1 states dominates. No structure is observed. The 5σ upper limit for the production of narrow states in the mass range 1100–1670 MeV is 2 × 10 −3 of all annihilations.

1 data table
Table 1

X means a narrow state.


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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Forward Particle Production in $\pi^- p$ and $K^- p$ Collisions at 58-{GeV}/$c$ and Comparison With Quark Models

The ACCMOR collaboration Pauß, F. ; Gonzalez-Arroyo, A. ; Ochs, W. ; et al.
Z.Phys.C 27 (1985) 211, 1985.
Inspire Record 206988 DOI 10.17182/hepdata.16120

We present single inclusive π±, π0 andK± spectra in the forward fragmentation region (x>0.2,pT<1.5 GeV/c) as well as correlations between two charged particles. The data were recorded in an unseparated negative hadron beam at the CERN SPS using a large acceptance forward spectrometer. Our maasurements are compared in detail with several models which emphasise the role of the beam valence quarks in this production process. The connection to measurements at largepT is also investigated.

3 data tables
Table 1

ERRORS INCLUDE SYSTEMATIC ERRORS BUT NOT OVERALL NORMALISATION UNCERTAINTY OF 8PCT.

Table 2

ERRORS INCLUDE SYSTEMATIC ERRORS BUT NOT OVERALL NORMALISATION UNCERTAINTY OF 8PCT.

Table 3

ERRORS INCLUDE SYSTEMATIC ERRORS BUT NOT OVERALL NORMALISATION UNCERTAINTY OF 8PCT.


MEASUREMENTS OF THE STRUCTURE FUNCTIONS F2 (x, Q**2) FROM neutrino p AND ANTI-NEUTRINO p INTERACTIONS

The WA21 collaboration Grassler, H. ; Lanske, D. ; Schulte, R. ; et al.
OXFORD NP-79/84, 1984.
Inspire Record 15788 DOI 10.17182/hepdata.1180

None

2 data tables
Table 1

NORMALISATION UNCERTAINTY IS 7 PCT.

Table 2

NORMALISATION UNCERTAINTY IS 7 PCT.


A MEASUREMENT OF ALPHA-ALPHA ELASTIC SCATTERING AT THE CERN ISR

The Axial Field Spectrometer collaboration Akesson, T. ; Albrow, M.G. ; Almehed, S. ; et al.
Phys.Lett.B 152 (1985) 140-144, 1985.
Inspire Record 206315 DOI 10.17182/hepdata.30430

We present measurements of the αα elastic scattering differential cross section at √ s = 126 GeV in the range 0.05 ⩽ ‖ t ‖

3 data tables
Table 1

ERRORS ARE STATISTICAL ONLY.

Table 2

EXPONENTIAL FIT TO CROSS SECTION BELOW T = 0.075 GEV**2.

Table 3

OPTICAL THEOREM CALCULATION OF THE TOTAL CROSS SECTION ASSUMING RHO IS ZERO.


Studies of Quark and Diquark Fragmentation Into Identified Hadrons in Deep Inelastic Muon - Proton Scattering

The European Muon collaboration Arneodo, M. ; Arvidson, A. ; Aubert, J.J. ; et al.
Phys.Lett.B 150 (1985) 458, 1985.
Inspire Record 206297 DOI 10.17182/hepdata.30438

None

19 data tables
Table 1

Backward Multiplicity.

Table 2

Forward Multiplicity.

Table 3

No description provided.

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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.


STUDY OF BOSE-EINSTEIN CORRELATIONS IN e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Bakken, J.A. ; et al.
Phys.Rev.D 31 (1985) 996, 1985.
Inspire Record 205870 DOI 10.17182/hepdata.23563

Bose-Einstein correlations between like-sign pions have been investigated in e+e− annihilation at √s =29 GeV using the Time Projection Chamber detector at the SLAC e+e− storage ring PEP. The production rate of like-sign pion pairs with small relative momentum is found to be increased by more than 50% over the rate expected for uncorrelated production of pions. From the correlation length, a typical source radius of 0.65 fm is derived. Data are consistent with a spherical shape of the pion source. No dependence of radius or correlation strength on the event multiplicity is observed.

1 data table
Table 1

No description provided.


rivet Analysis
INCLUSIVE gamma AND pi0 PRODUCTION CROSS-SECTIONS AND ENERGY FRACTIONS IN e+ e- ANNIHILATION AT 29-GeV

The TPC/Two Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Bakken, J.A. ; et al.
Z.Phys.C 27 (1985) 187, 1985.
Inspire Record 205868 DOI 10.17182/hepdata.16101

Inclusive production cross sections for photons and π0's ine+e− annihilation at a center of mass energy of 29 GeV have been measured. The π0 production spectrum agrees with a corresponding measurement for π±. The ratio of the π0 inclusive rate to the average for π± is 0.92±0.14. The fractions of the total energy carried by photons and π0's are 0.244±0.016 and 0.217±0.033, respectively. The fraction of total energy carried by all stable hadrons, prompt leptons and photons is determined to be 0.938±0.045, leaving 0.062±0.045 for neutrinos.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Charged Particle Spectra in $\alpha \alpha$ and $\alpha p$ Collisions at the {CERN} {ISR}

The CERN-Heidelberg-Lund collaboration Bell, W. ; Braune, K. ; Glaesson, G. ; et al.
Z.Phys.C 27 (1985) 191, 1985.
Inspire Record 205679 DOI 10.17182/hepdata.16095

Momenta of charged particles produced in inelastic αα, αp, andpp collisions were measured using the Split-Field-Magnet detector at the CERN Intersecting Storage Rings. Inclusive and semi-in-clusive spectra are presented as a function of rapidityy, Feynman-x, and transverse momentumpT. The inclusivey distributions agree well with predictions of the dual parton model; the highest particle densities are reached aty≃0 and the momenta of leading protons decrease significantly for increasing total multiplicity. ‘Temperatures’ are equal in αα, αp, andpp interactions. ThepT distributions depend weakly on the multiplicity.

6 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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