Derebchinsky, A.I.
Polarization
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Tensor analyzing power T(20) in backward elastic d p scattering and breakup at 0-degrees between 3.5-GeV/c and 6.5-GeV/c

Azhgirey, L.S. ; Chernykh, E.V. ; Kobushkin, A.P. ; et al.
Phys.Lett.B 391 (1997) 22-28, 1997.
Inspire Record 456818 DOI 10.17182/hepdata.28323

The tensor analyzing power T 20 for the p ( d , p d) and p ( d , p ) pn reactions θ cm p = 180° have been measured at incident deuteron momenta from 3.5 to 6.5 GeV/ c . For both reactions T 20 remains negative up to internal momentum k ⋍ 0.85 GeV/ c and show a rich structure beyond the region where T 20 is expected to be determined by the S - and D -states of the deuteron. The T 20 data for deuteron breakup without pion production, close to the backward elastic kinematics, were obtained simultaneously with the elastic data.

1 data table
Table 1

K is the internal momentum of the nucleon.


Measurement of the spin rotation parameters R and A in pi- p elastic scattering at 450-MeV and 560-MeV

Abaev, V.V. ; Bazhanov, N.A. ; Bekrenev, V.S. ; et al.
Sov.J.Nucl.Phys. 48 (1988) 852-858, 1988.
Inspire Record 457307 DOI 10.17182/hepdata.17344
3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


A precise measurement of the tau polarization and its forward-backward asymmetry at LEP.

The OPAL collaboration Alexander, G. ; Allison, John ; Altekamp, N. ; et al.
Z.Phys.C 72 (1996) 365-375, 1996.
Inspire Record 421815 DOI 10.17182/hepdata.47776

A measurement of theτ lepton polarization and its forward-backward asymmetry at the Z0 resonance using the OPAL detector is described. The measurement is based on analyses of τ→ρντ, ττπ(K)ντ,\(\tau\to e\bar \nu _e \nu _\tau\),\(\tau\to \mu \bar \nu _\mu\nu _\tau\) andτ→a1ντ decays from a sample of 89075 e+e−→τ+τ− candidates corresponding to an integrated luminosity of 117 pb−1. Assuming that theτ lepton decays according to V-A theory, we measure the averageτ polarization at √s=MZ to be 〈P〉=(−13.0±0.9±0.9)% and theτ polarization forward-backward asymmetry to be ApolFB=(−9.4±1.0±0.4)%, where the first error is statistical and the second systematic. These results are consistent with the hypothesis of lepton universality and, when combined, can be expressed as a measurement of sin2θefflept=0.2334±0.0012 within the context of the Standard Model.

1 data table
Table 1

No description provided.


Measurement of the total cross-section difference Delta(sigma-L) in n p transmission at 1.19-GeV, 2.49-GeV and 3.65-GeV

Adiasevich, B.P. ; Antonenko, V.G. ; Averichev, S.A. ; et al.
Z.Phys.C 71 (1996) 65-74, 1996.
Inspire Record 416847 DOI 10.17182/hepdata.12108

Results of the total cross section differenceΔσL in anp transmission experiment at 1.19, 2.49 and 3.65 GeV incident neutron beam kinetic energies are presented. Measurements were performed at the Synchrophasotron of the Laboratory of High Energies of the Joint Institute for Nuclear Research in Dubna. Results were obtained with a polarized beam of free quasi-monochromatic neutrons passing through the new Dubna frozen spin proton target. The beam and target polarizations were oriented longitudinally. The present results were obtained at the highest energies of free polarized neutrons that can be reached at present. They extend the energy range of existing results from PSI, LAMPF and Saclay measured between 0.066 and 1.10 GeV. The new results are compared withΔσL(pn) data determined as a difference betweenΔσL(pd) andΔσL(pp) ANL-ZGS measurements. The values ofΔσL for the isospin stateI=0 were deduced using knownpp data.

2 data tables
Table 1

Errors contain statistical and systematic errors added in quadrature. Axis error includes +- 0.05/0.05 contribution (An additional error due to the extrapolation towards zero solid angle).

Table 2

No description provided.


Polarization observables in pi d (polarized) elastic scattering: Analyzing powers tau (22) and iT (11) in the forward hemisphere

Wessler, M. ; Boschitz, E. ; Brinkmoeller, B. ; et al.
Phys.Rev.C 51 (1995) 2575-2583, 1995.
Inspire Record 405002 DOI 10.17182/hepdata.25896

The vector analyzing power iT11 and the composite observable τ22=T22+T20/ √6 were measured at 10 incident pion energies between 100 and 294 MeV, in an angular range between 50° and 120°. Two different techniques were applied, the detection of the pion with a magnet spectrometer, and the πd coincidence method with scintillation counters. In the case of the first technique also two different target materials were used. Consistency among all data was obtained. The experimental data are compared to Faddeev calculations from one of us (H.G.). The discrepancies between theory and experiment are discussed, and an outlook for further research is given.

14 data tables
Table 1

Vector analyzing power iT11 and composite observale TAU22 = T22 + T20/sqrt(6). LiDeut target.

Table 2

Vector analyzing power iT11 and composite observale TAU22 = T22 + T20/sqrt(6). LiDeut target.

Table 3

Vector analyzing power iT11 and composite observale TAU22 = T22 + T20/sqrt(6). LiDeut target.

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Measurement of the spin rotation parameter A+ in the elastic scattering of positive pions on a longitudinally polarized proton target in the second resonance region

The ITEP-PNPI collaboration Alekseev, I.G. ; Bobchenko, B.M. ; Budkovsky, P.E. ; et al.
Phys.Lett.B 351 (1995) 585-590, 1995.
Inspire Record 403317 DOI 10.17182/hepdata.28540

The ITEP-PNPI collaboration presents the first results of the spin rotation parameter A + measurements in the second resonance region. The experiment was performed at the ITEP accelerator at a positive pion beam momentum 1.43 GeV/c for scattering angles θ cm = 127° and 133°. The setup was based on a polarized proton target and a carbon-plate polarimeter. The obtained data is compared with the predictions of the existing partial-wave analyses.

1 data table
Table 1

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.


Observation of significant spin effects in hard collisions at 40-GeV/c

Apokin, V.D. ; Arestov, Yu.I. ; Astafev, O.V. ; et al.
Phys.Lett.B 243 (1990) 461-464, 1990.
Inspire Record 303587 DOI 10.17182/hepdata.29694

A single-spin asymmetry in the inclusive π 0 production at small x F was measured. In the experiment 40 GeV/c π − mesons were incident on transversely polarized protons and deutrons. An asymmetry of (40–50)% has been revealed in the hard scattering region.

1 data table
Table 1

No description provided.


Polarization parameters A(000n) and A(00nn) in elastic proton proton scattering in the energy region 690-MeV to 890-MeV

Vovchenko, V.G. ; Efimovykh, V.A. ; Zhdanov, A.A. ; et al.
Sov.J.Nucl.Phys. 49 (1989) 446-453, 1989.
Inspire Record 292935 DOI 10.17182/hepdata.17325

None

3 data tables
Table 1

Axis error includes +- 0.0/0.0 contribution (DUE TO QUAZIELASTIC BACKGROUND AND ERRORS IN POLARIZATION OF BEAM AND TARGET).

Table 2

Axis error includes +- 0.0/0.0 contribution (DUE TO QUAZIELASTIC BACKGROUND AND ERRORS IN POLARIZATION OF BEAM AND TARGET).

Table 3

Axis error includes +- 0.0/0.0 contribution (DUE TO QUAZIELASTIC BACKGROUND AND ERRORS IN POLARIZATION OF BEAM AND TARGET).


OBSERVATION OF THE ASYMMETRY IN THE REACTION pi- p (polarized) ---> (pi0 pi0) n

Apokin, V.D. ; Belikov, N.I. ; Derevshchikov, A.A. ; et al.
Sov.J.Nucl.Phys. 47 (1988) 465, 1988.
Inspire Record 246899 DOI 10.17182/hepdata.40790

None

2 data tables
Table 1

No description provided.

Table 2

No description provided.