Babou, M.
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High precision measurement of A in large P(T)**2 spin polarized 24-GeV/c proton proton elastic scattering

Crabb, D.G. ; Kaufman, W.A. ; Krisch, A.D. ; et al.
Phys.Rev.Lett. 65 (1990) 3241-3244, 1990.
Inspire Record 299843 DOI 10.17182/hepdata.19939

We measured the analyzing power A out to P⊥2=7.1 (GeV/c)2 with high precision by scattering a 24-GeV/c unpolarized proton beam from the new University of Michigan polarized proton target; the target’s 1-W cooling power allowed a beam intensity of more than 2×1011 protons per pulse. This high beam intensity together with the unexpectedly high average target polarization of about 85% allowed unusually accurate measurements of A at large P⊥2. These precise data confirmed that the one-spin parameter A is nonzero and indeed quite large at high P⊥2; most theoretical models predict that A should go to zero.

1 data table
Table 1

Errors quoted contain both statistical and systematic uncertainties.


Neutral strange particle production in sulphur sulphur and proton sulphur collisions at 200-GeV/nucleon

The NA35 collaboration Bartke, J. ; Bialkowska, H. ; Bock, R. ; et al.
Z.Phys.C 48 (1990) 191-200, 1990.
Inspire Record 304994 DOI 10.17182/hepdata.15177

The production of Λ,\(\bar \Lambda\) andKs0 has been studied in 200 GeV/nucleonp+S and S+S collisions in the streamer chamber of the NA35 experiment at the CERN SPS. Significant enhancement of the multiplicities of all observed strange particles relative to negative hadrons was observed in central S+S collisions, as compared top+p andp+S collisions. The latter collisions show no overall (relative) strangeness enhancement overp+p, but the rapidity distributions and hadron multiplicities indicate some secondary cascading production of Λ particles in thep+S andp+Au collisions. The Λ polarization in central S+S collisions was found to be compatible with zero up topT=2 GeV/c.

15 data tables
Table 1

Tranverse kinetic energy spectra of neutral strange particles in P SU collisions.

Table 2

Tranverse kinetic energy spectra of neutral strange particles in P SU collisions.

Table 3

Tranverse kinetic energy spectra of neutral strange particles in SU SU collisions.

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Measurement of the analyzing power and the differential cross-section of the anti-p p charge exchange reaction at LEAR

Birsa, R. ; Bradamante, F. ; Dalla Torre-Colautti, S. ; et al.
Phys.Lett.B 246 (1990) 267-272, 1990.
Inspire Record 296501 DOI 10.17182/hepdata.29676

As part of a programme to study the spin structure of the p p→ n n channel, we have measured the analysing power A 0 n and the differential cross section at an incident antiproton beam momentum of 704 MeV/ c . The analysing power exhibits a remarkable angular dependence, which is poorly reproduced by the existing potential models.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Polarized target asymmetry in pion proton bremsstrahlung at 298-MeV

Bosshard, A. ; Amsler, Claude ; Bistirlich, J.A. ; et al.
Phys.Rev.Lett. 64 (1990) 2619-2622, 1990.
Inspire Record 303404 DOI 10.17182/hepdata.22827

First data are presented for the polarized-target asymmetry in the reaction π+p→π+pγ at an incident pion energy of 298 MeV. The geometry was chosen to maximize the sensitivity to the radiation of the magnetic dipole moment μΔ of the Δ++(1232 MeV). A fit of the asymmetry in the cross section d5σ/dΩπ dΩγ dk as a function of the photon energy k to predictions from a recent isobar-model calculation with μΔ as the only free parameter yields μΔ=1.64(±0.19expΔ,±0.14 theor)μp. Though this value agrees with bag-model corrections to the SU(6) prediction μΔ=2μp, further clarifications on the model dependence of the result are needed, in particular since the isobar model fails to describe both the cross section and the asymmetry at the highest photon energies.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Analyzing power for pi- p charge exchange in the backward hemisphere from 301-MeV/c to 625-MeV/c and a test of pi N partial wave analyses

Kim, G.J. ; Arends, J. ; Engelage, J. ; et al.
Phys.Rev.D 41 (1990) 733-743, 1990.
Inspire Record 301242 DOI 10.17182/hepdata.22935

The analyzing power of π−p→π0n has been measured for pπ=301−625 MeV/c with a transversely polarized target, mainly in the backward hemisphere. The final-state neutron and a γ from the π0 were detected in coincidence with two counter arrays. Our results are compared with predictions of recent πN partial-wave analyses by the groups of Karlsruhe-Helsinki, Carnegie-Mellon University-Lawrence Berkeley Laboratory (CMU-LBL), and Virginia Polytechnic Institute (VPI). At the lower incident energies little difference is seen among the three analyses, and there is excellent agreement with our data. At 547 MeV/c and above, our data strongly favor the VPI phases, and disagree with Karlsruhe-Helsinki and CMU-LBL analyses, which are the source of the πN resonance parameters given in the Particle Data Group table.

7 data tables
Table 1

Axis error includes +- 5/5 contribution (Uncertainty in background normalisation).

Table 2

Axis error includes +- 5/5 contribution (Uncertainty in background normalisation).

Table 3

Axis error includes +- 5/5 contribution (Uncertainty in background normalisation).

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Proton proton bremsstrahlung at 280-MeV

Michaelian, K. ; Kitching, P. ; Hutcheon, D.A. ; et al.
Phys.Rev.D 41 (1990) 2689-2704, 1990.
Inspire Record 304884 DOI 10.17182/hepdata.23001

A proton-proton bremsstrahlung experiment has been carried out at TRIUMF using a 280-MeV polarized proton beam impinging on a liquid-hydrogen target. All three outgoing particles were detected: the higher-energy proton in a magnetic spectrometer, the lower-energy proton with plastic scintillators, and the photon in lead-glass Cherenkov detectors. The experiment shows the first unambiguous evidence for off-shell effects in the free nucleon-nucleon interaction, in that the analyzing powers disagree strongly with the predictions of the soft-photon approximation (which incorporates only on-shell information) but are consistent with the results of calculations using the Bonn and Paris potentials.

8 data tables
Table 1

Estimated scale uncertainty is 1.5 pct.

Table 2

Estimated scale uncertainty is 1.5 pct.

Table 3

Estimated scale uncertainty is 1.5 pct.

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Analyzing power of inclusive production of pi+, pi-, and K0(S) by polarized protons at 13.3-GeV/c and 18.5-GeV/c

Bonner, B.E. ; Buchanan, J.A. ; Clement, J.M. ; et al.
Phys.Rev.D 41 (1990) 13-16, 1990.
Inspire Record 299995 DOI 10.17182/hepdata.23009

We have measured the analyzing power in π+, π−, and KS0 production by a polarized proton beam at 13.3 and 18.5 GeV/c. The data cover the central and the beam fragmentation region, in the transverse-momentum range up to 2 GeV/c. The results indicate that sizable effects are present at high xF and also persist into the hard-scattering region for KS0 and π+. A zero value of the analyzing power was observed for π− production.

13 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurement of the Analyzing Power in the Primakoff Process With a High-energy Polarized Proton Beam

The FERMILAB E-704 collaboration Carey, David C. ; Coleman, R.N. ; Corcoran, M.D. ; et al.
Phys.Rev.Lett. 64 (1990) 357, 1990.
Inspire Record 282042 DOI 10.17182/hepdata.19957

The analyzing power (spin-dependent azimuthal asymmetry) has been observed for the first time in the nuclear Coulomb coherent production process, the ‘‘Primakoff process,’’ with the use of the newly constructed 185-GeV/c Fermilab polarized proton beam. We have observed a large asymmetry of this process in the regions of ‖t’‖<0.001 (GeV/c)2 and 1.36

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Full Angular Distribution of the Analyzing Power in $\bar{p} p$ Elastic Scattering at 697-{MeV}/$c$

Bertini, R. ; Costa, M. ; Perrot, F. ; et al.
Phys.Lett.B 228 (1989) 531-535, 1989.
Inspire Record 280163 DOI 10.17182/hepdata.29779

Full angular distributions of the differential cross-section dσ/dμ and of the analysing power A y in p p elastic scattering have been measured at 697 MeV/ c . The results of A y are compared with the predictions of various theoretical models.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

Legendre Polynomials from fit to angular distribution (LEG(L=0)=3.59 +- 0.02).


Analyzing Power Measurements of Coulomb Nuclear Interference With the Polarized Proton and Anti-proton Beams at 185 GeV/c

The E581/704 collaboration Akchurin, N. ; Carey, David C. ; Coleman, R. ; et al.
Phys.Lett.B 229 (1989) 299-303, 1989.
Inspire Record 280476 DOI 10.17182/hepdata.29782

The analyzing power A N of proton-proton, proton-hydrocarbon, and antiproton-hydrocarbon, scattering in the Coulomb-nuclear interference region has been measured using thhe 185 GeV/ c Fermilab polarized-proton and -antiproton beams. The results are found to be consistent with theoretical predictions within statistical uncertainties.

3 data tables
Table 1

No description provided.

Table 2

Data from hydrocarbon target.

Table 3

Data from hydrocarbon target.