Date

Subject_areas

A Search for jet handedness in hadronic Z0 decays

The SLD collaboration Abe, K. ; Abt, I. ; Ahn, C.J. ; et al.
Phys.Rev.Lett. 74 (1995) 1512-1516, 1995.
Inspire Record 378343 DOI 10.17182/hepdata.19666

We have searched for signatures of polarization in hadronic jets from $Z~0 \rightarrow q \bar{q}$ decays using the ``jet handedness'' method. The polar angle asymmetry induced by the high SLC electron-beam polarization was used to separate quark jets from antiquark jets, expected to be left- and right-polarized, respectively. We find no evidence for jet handedness in our global sample or in a sample of light quark jets and we set upper limits at the 95\% C.L. of 0.063 and 0.099 respectively on the magnitude of the analyzing power of the method proposed by Efremov {\it et al.}

1 data table

Polarized E- beam. Events were classified as being of light or heavy flavors based on impact parameters of charged tracks measured in the vertex detector. Jet handedness are measured for helicity-based and chirality-based analysis (seetext). C=95PCT CL indicates the upper limits at the 95 PCT C.L. on the magnitudes.


Measurement of the polarization of tau leptons produced in Z decays

The ALEPH collaboration Decamp, D. ; Deschizeaux, B. ; Goy, C. ; et al.
Phys.Lett.B 265 (1991) 430-444, 1991.
Inspire Record 316781 DOI 10.17182/hepdata.29377

The polarization of τ leptons produced in the reaction e + e − → τ + τ − at the Z resonance has been measured using the τ decay modes e ν e ν τ , μν μ ν τ , πν τ , ϱν τ , and a 1 ν τ . The mean value obtained is P τ = −0.152±0.045, indicating that parity is violated in the neutral current process e + e − → τ + τ − . The result corresponds to a ratio of a neutral current vector and axial vector coupling constants of the τ lepton g V τ (M 2 Z ) g A τ (M 2 Z ) = 0.076±0.023 and a value of the electroweak mixing parameter sin 2 θ w ( M 2 Z ) = 0.2302 ± 0.0058.

2 data tables

Results are for both TAU+ and TAU- decay. Final combined result contains statistical and systematic errors added in quadrature.

No description provided.


An investigation of the spin structure of the proton in deep inelastic scattering of polarized muons on polarized protons.

The European Muon collaboration Ashman, J. ; Badelek, B. ; Baum, Guenter ; et al.
Nucl.Phys.B 328 (1989) 1, 1989.
Inspire Record 280143 DOI 10.17182/hepdata.49587

The spin asymmetry in deep inelastic scattering of longitudinally polarised muons by longitudinally polarised protons has been measured in the range 0.01<×<0.7. The spin dependent structure function g 1 ( x ) for the proton has been determined and, combining the data with earlier SLAC measurements, its integral over x found to be 0.126±0.010(stat.)±0.015(syst.), in disagreement with the Ellis-Jaffe sum rule. Assuming the validity of the Biorken sum rule, this result implies a significant negative value for the integral of g 1 for the neutron. These integrals lead to the conclusion, in the naïve quark parton model, that the total quark spin constitutes a rather small fraction of the spin of the nucleon. Results are also presented on the asymmetries in inclusive hadron production which are consistent with the above picture.

7 data tables

THE MEAN Q**2 FOR EACH OF THE 10 VALUES OF X BELOW ARE 3.5,4.5,6.0, 8.010.3,12.9,15.2,18.0,22.5,29.5.

No description provided.

No description provided.

More…

The Polarized Target Asymmetry in Photoproduction of $\Eta$ Mesons From Protons at 4-{GeV}

Bussey, P.J. ; Raine, C. ; Rutherglen, J.G. ; et al.
Nucl.Phys.B 185 (1981) 269-273, 1981.
Inspire Record 155784 DOI 10.17182/hepdata.34276

Measurements have been made of the polarised target asymmetry parameter T for eta photoproduction from protons at a photon energy of 4 GeV and t -values of −0.4, −0.6 and −0.8 (GeV/ c ) 2 . The results are compared with predictions for this quantity.

1 data table

No description provided.


Polarization in $K^+ n$ Charge Exchange Scattering Between 0.851-{GeV}/$c$ and 1.351-{GeV}/$c$

Watts, S.J. ; Bugg, D.V. ; Carter, A.A. ; et al.
Phys.Lett.B 95 (1980) 323, 1980.
Inspire Record 154475 DOI 10.17182/hepdata.27149

The polarization parameter for K + n charge exchange scattering has been measured at five momenta between 0.851 GeV/ c and 1.351 GeV/ c for centre of mass angles −0.8 < cos θ ∗ < 0.8 . Results from a phase shift analysis incorporating these results are presented. No Z ∗ resonances are observed.

5 data tables

No description provided.

No description provided.

No description provided.

More…

Measurement of Polarization in $K^+ N$ Elastic Scattering Between 0.851-{GeV}/c and 1.351-{GeV}/c

Robertson, A.W. ; Astbury, A. ; Grayer, G.H. ; et al.
Phys.Lett.B 91 (1980) 465-469, 1980.
Inspire Record 152628 DOI 10.17182/hepdata.27196

The polarizaton parameter has been measured for K + n elastic scatteringat five incident beam momenta between 0.851 GeV/ c and 1.351 GeV/ c for c.m. angles in the range −0.9 < cos θ ∗ < 0.9 . It is in good agreement with the most recent partial wave analysis of the KN system.

5 data tables

No description provided.

No description provided.

No description provided.

More…

MEASUREMENT OF POLARIZATION IN K- p ELASTIC SCATTERING BETWEEN 0.955-GeV/c AND 1.272-GeV/c

Bryant, H.C. ; Carter, A.A. ; Coupland, M. ; et al.
Nucl.Phys.B 168 (1980) 207-221, 1980.
Inspire Record 143628 DOI 10.17182/hepdata.34502

The polarization parameter has been measured for K − p elastic scattering at nine incident beam momenta between 0.955 and 1.272 GeV/ c covering the c.m. angular range −0.9 < cos θ ∗ < + 0.9 . Experimental results and coefficients of Legendre polynomial fits to the data are presented and compared with other measurements and a partial-wave analysis.

2 data tables

No description provided.

LEGENDRE POLYNOMIAL COEFFICIENTS FOR POLARIZATION DERIVED USING INTERPOLATED DIFFERENTIAL CROSS SECTION DATA OF B. CONFORTO ET AL., NP B105, 189 (1976).


Polarization Parameters in Positive Pion Photoproduction

Bussey, P.J. ; Raine, C. ; Rutherglen, J.G. ; et al.
Nucl.Phys.B 154 (1979) 205-225, 1979.
Inspire Record 140382 DOI 10.17182/hepdata.43832

Measurements have been made of the polarisation parameters Σ , T and P for the process γ p → π + n in the photon energy range 520–2250 MeV at c.m. angles between 30° and 120°. These data were obtained in a double polarisation experiment, using the polarised photon beam from the Daresbury electron synchrotron incident on a polarised proton target. The data are compared with predictions from current theoretical analyses.

2 data tables

No description provided.

No description provided.


Polarization Parameters in Neutral Pion Photoproduction

Bussey, P.J. ; Raine, C. ; Rutherglen, J.G. ; et al.
Nucl.Phys.B 154 (1979) 492-502, 1979.
Inspire Record 140230 DOI 10.17182/hepdata.34681

The polarisation parameters Σ, P and T have been measured for the process γ p→ π 0 p in the photon energy range 1300–2100 MeV and c.m. angles between 30° and 110°, in an experiment with a polarised beam and polarised target. The results are compared with a recent theoretical analysis which fits data from threshold to 16 GeV. The new data are in general agreement with the analysis, but with some significant discrepancies in detail.

9 data tables

No description provided.

No description provided.

No description provided.

More…

The Normalization of p p Polarization Between 200-MeV and 520-MeV

Amsler, C. ; Bugg, D.V. ; Axen, D. ; et al.
J.Phys.G 4 (1978) 1047-1053, 1978.
Inspire Record 135489 DOI 10.17182/hepdata.38559

The absolute normalisation of the polarisation in pp elastic scattering at 24 degrees lab has been determined by means of a double-scattering experiment to an accuracy of +or-1.5% at five energies between 200 and 520 MeV.

1 data table

No description provided.