HEPData Search

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Measurement of the analyzing power in anti-p p elastic scattering at 439-MeV/c and 544 MeV/c

Kunne, F. ; Bertini, R. ; Costa, M. ; et al.

Phys.Lett.B 261 (1991) 188-190, 1991.

Inspire Record 314564 DOI 10.17182/hepdata.29399

The angular distributions of the analyzing power A y and of the differential cross section d σ/ d Ω in p p elastic scattering have been measured at 439 and 544 MeV/c. The results of A y are compared with various theoretical models.

4 data tables

Table 1

Data requested from authors.

Table 2

Legendre fit polynomials.

Table 3

Normalized Legendre fit polynomials.

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rivet Analysis
Test of spin dependence in charm-quark fragmentation to D*.

The TPC/Two-Gamma collaboration Aihara, H. ; Alston-Garnjost, M. ; Avery, R.E. ; et al.

Phys.Rev.D 43 (1991) 29-33, 1991.

Inspire Record 316132 DOI 10.17182/hepdata.22830

We have measured the polarization of D*, the energy dependence of the polarization, and the spin-density matrix of D* in e+e− annihilation at a center-of-mass energy of 29 GeV using the Time Projection Chamber detector at the SLAC storage ring PEP. In 147 pb−1 of data we see no strong evidence for polarization, alignment, or final-state interactions in this fragmentation process.

2 data tables

Table 1

Polarization is the factor alpha(z) in the expression d width (D*-->D pi)/domega = C(1+alpha(z)cos(theta)**2).

Table 2

Spin density matrices for D* --> D0 pi+.

rivet Analysis
Charged particle multiplicity distributions in restricted rapidity intervals in Z0 hadronic decays.

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adami, F. ; et al.

Z.Phys.C 52 (1991) 271-281, 1991.

Inspire Record 324035 DOI 10.17182/hepdata.14860

The multiplicity distributions of charged particles in restricted rapidity intervals inZ0 hadronic decays measured by the DELPHI detector are presented. The data reveal a shoulder structure, best visible for intervals of intermediate size, i.e. for rapidity limits around ±1.5. The whole set of distributions including the shoulder structure is reproduced by the Lund Parton Shower model. The structure is found to be due to important contributions from 3-and 4-jet events with a hard gluon jet. A different model, based on the concept of independently produced groups of particles, “clans”, fluctuating both in number per event and particle content per clan, has also been used to analyse the present data. The results show that for each interval of rapidity the average number of clans per event is approximately the same as at lower energies.

15 data tables

Table 1

Data for both hemispheres.

Table 2

Data for both hemispheres.

Table 3

Data for both hemispheres.

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Inclusive production of $\pi^0$ mesons in $\pi$p, Kp and $\gamma$p collisions at energies around 100-GeV.

The Omega Photon collaboration Apsimon, R.J. ; Atkinson, M. ; Baake, M. ; et al.

Z.Phys.C 52 (1991) 397-405, 1991.

Inspire Record 325149 DOI 10.17182/hepdata.14858

Measurements are reported of inclusive production of π0-mesons in the beam fragmentation region in γp, πp andKp collisions. Results include the ratio of π0 production inKp and πp collisions, showing reduced production from fragmentation of theK-meson, and the ratio of π0 production in photon and hadron collisions which shows agreement with modified Vector Meson Dominance at lowPT, and departures at higherPT signalling the onset of direct photon reactions. The pattern of departure from Feynman scaling at highPT points to a contribution of hard parton-parton collisions in both γp and πp collisions.

28 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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The Study of reactions with deuteron and pions in the final state by n p and d p interactions comparison

Glagolev, V.V. ; Troian, Yu.A. ; Lebedev, R.M. ; et al.

Dubna JINR - 91-511 (91/12,rec.Mar.92) 24 p, 1991.

Inspire Record 325758 DOI 10.17182/hepdata.39328

None

3 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

Measurement of the tensor analyzing power T(20) in inclusive deuteron breakup at 9-GeV/c on hydrogen and carbon

Azhgirey, L.S. ; Afanasyev, S.V. ; Chernykh, E.V. ; et al.

Phys.Lett.B 387 (1996) 37-42, 1996.

Inspire Record 328522 DOI 10.17182/hepdata.28341

The tensor analyzing power T 20 in inclusive deuteron breakup at 9 GeV/c and 0° on hydrogen and carbon targets up to internal momenta k of the proton in the deuteron of ∼ 1 GeV/c has been measured. The analyzing power remains negative up to the highest measured values of k , and is in definite disagreement with predictions from several theoretical models. A systematic difference between T 20 for deuteron breakup on hydrogen and carbon is observed.

2 data tables

Table 1

No description provided.

Table 2

No description provided.

A measurement of the Z0 invisible width by single photon counting.

The OPAL collaboration Akrawy, M.Z. ; Alexander, G. ; Allison, John ; et al.

Z.Phys.C 50 (1991) 373-384, 1991.

Inspire Record 302586 DOI 10.17182/hepdata.14980

The OPAL detector at LEP is used to measure the branching ratio of theZ0 into invisible particles by measuring the cross section of single photon events ine+e− collisions at centre-of-mass energies near theZ0 resonance. In a data sample of 5.3 pb−1, we observe 73 events with single photons depositing more than 1.5 GeV in the electromagnetic calorimeter, with an expected background of 8±2 events not associated with invisibleZ0 decay. With this data we determine theZ0 invisible width to be 0.50±0.07±0.03 GeV, where the first error is statistical and the second systematic. This corresponds to 3.0±0.4±0.2 light neutrino generations in the Standard Model.

1 data table

Table 1

No description provided.