Measurement of the polarization parameter in pi- p backward elastic scattering at 6-GeV/c

The CERN-Orsay-Oxford collaboration Dick, L. ; Janout, Z. ; Aoi, H. ; et al.
Nucl.Phys.B 64 (1973) 45-57, 1973.
Inspire Record 94951 DOI 10.17182/hepdata.32420

The polarization parameter in π − p elastic scattering has been measured in the backward angular region at an incident momentum of 6 GeV/ c . The measurements cover the range of four momentum transfer u = 0 to −1 (GeV/ c ) 2 , and were obtained with a high intensity pion beam, a butanol polarized proton target, and arrays of scintillation counter hodoscopes. The polarization is different from zero, in contradiction to the prediction of the naive one trajectory Regge-exchange model. It increases positively with the four-momentum transfer u, reaching a maximum of about 0.4 at u ≈ −0.3 (GeV/c)2. It then decreases and becomes slightly negative beyond u ≈ −0.5 (GeV/c)2. A variety of baryon exchange models are briefly reviewed and none are found to be in complete agreement with all the experimental data.

1 data table match query

No description provided.


Measurement of the polarization parameter in pi+ p backward elastic scattering at 6-GeV/c

The CERN-IPN Orsay-Oxford collaboration Dick, L. ; Janout, Z. ; Aeoi, H. ; et al.
Nucl.Phys.B 43 (1972) 522-540, 1972.
Inspire Record 75086 DOI 10.17182/hepdata.32869

The polarization parameter in π + p backward elastic scattering at 6 GeV/ c incident pion momentum has been measured using a butanol polarized proton target, a high intensity pion beam, and a scintillation hodoscope detection system. Details of the apparatus and data analysis are presented here, together with the final results.

1 data table match query

No description provided.


A Measurement of the Polarization Parameter in Large Angle Proton Proton Elastic Scattering at 7.9-GeV/c

Aschman, D.G. ; Crabb, D.G. ; Green, K. ; et al.
Nucl.Phys.B 125 (1977) 349-368, 1977.
Inspire Record 125075 DOI 10.17182/hepdata.35322

The polarization parameter in proton-proton elastic scattering has been measured at an incident momentum of 7.9 GeV/ c and four-momentum transfers in the range 0.9 < | t | < 6.5 (GeV/ c ) 2 using a high intensity unpolarized proton beam incident on a polarized proton target. The angle and momentum of the forward scattered protons were measured with a magnet spectrometer and scintillation counter hodoscopes and the angle of the recoil proton was measured using similar hodoscopes. A clean separation between the elastic scattering from free hydrogen and that coming from inelastic interactions and from interactions with complex nuclei in the target was obtained. The polarization shows substantial structure rising from zero at | t | = 1.0 (GeV/ c ) 2 to a maximum at | t | = 1.7 (GeV/ c ) 2 and then falling to zero at | t | = 2.0 (GeV/ c ) 2 . There is evidence of a further peak at | t | = 2.8 (GeV/ c ) 2 . Above | t | = 3.25 (GeV/ c ) 2 the polarization is small and consistent with zero. A comparison of these data with data obtained at other beam momenta shows that the polarization parameter has a strong momentum dependence.

1 data table match query

No description provided.


Measurement of the Polarization Parameter in 24-GeV/c Proton Proton Elastic Scattering at Small Momentum Transfers

Crabb, D.G. ; Green, K. ; Kyberd, P. ; et al.
Nucl.Phys.B 121 (1977) 231-236, 1977.
Inspire Record 124254 DOI 10.17182/hepdata.35517

A measurement of the polarization parameter P 0 in pp elastic scattering has been made at 24 GeV/ c over the range | t | = 0.1 to 0.9 (GeV/ c ) 2 , positive, falling to zero around | t | = 0.8 (GeV/ c ) 2 . For the range 0.1 ⪕ |t| ⪕ 0.4 GeV /c) 2 , P 0 is constant at about 0.03.

1 data table match query

Axis error includes +- 5/5 contribution (SYS-ERR DUE MAINLY TO UNCERTAINTY IN KNOWLEDGE OF ABSOLUTE VALUE OF TARGET POLARIZATION).


Measurement of the Analyzing Power for $p p$ (Polarized) $\to p p$ at $p^-$transverse**2 = 6.5-{GeV}/$c^2$

Cameron, P.R. ; Crabb, D.G. ; DeMuth, G.E. ; et al.
Phys.Rev.D 32 (1985) 3070, 1985.
Inspire Record 216507 DOI 10.17182/hepdata.23543

The spin analyzing power A in 28-GeV/c proton-proton elastic scattering was measured at P⊥2=6.5 (GeV/c)2 using a polarized proton target and a high-intensity unpolarized proton beam at the Brookhaven National Laboratory Alternating Gradient Synchrotron. The result of (24±8)% confirms that the analyzing power is large and rising in the large-P⊥2 region.

1 data table match query

No description provided.


Large $p^-$transverse**2 Spin Effects in $p p \to p p$

Peaslee, D.C. ; O'Fallon, J.R. ; Simonius, M. ; et al.
Phys.Rev.Lett. 51 (1983) 2359, 1983.
Inspire Record 192857 DOI 10.17182/hepdata.20491

The analyzing power A in 28-GeV/c proton-proton elastic scattering was measured with a polarized proton target and a high-intensity unpolarized proton beam at the Brook-haven National Laboratory alternating-gradient synchrotron. The P⊥2 range of 2.85 to 5.95 (GeV/c)2 was covered with good precision. A small dip of about -3.5% was found near P⊥2=3.5 (GeV/c)2 where a 24-GeV/c CERN experiment had reported a deep dip of about -16% with large errors. In the previously unexplored large-P⊥2 region near 6 (GeV/c)2 these new large-error points suggest that A may be rising.

1 data table match query

No description provided.


Spin Effects in $p p$ Elastic Scattering at 28-{GeV}/$c$

Hansen, P.H. ; O'Fallon, J.R. ; Danby, G.T. ; et al.
Phys.Rev.Lett. 50 (1983) 802, 1983.
Inspire Record 182130 DOI 10.17182/hepdata.20535

The analyzing power, A, was measured in proton-proton elastic scattering with use of a polarized proton target and 28-GeV/c primary protons from the alternating-gradient synchrotron. Over the P⊥2 range of 0.5 to 2.8 (GeV/c)2, the data show interesting structure. There is a rather sharp dip at P⊥2=0.8 (GeV/c)2 corresponding to the break in the elastic differential cross section at the end of the diffraction peak.

1 data table match query

No description provided.


Analyzing power measurements in high‐P2∥ p‐p elastic scattering

Raymond, R.S. ; Brown, K.A. ; Bruni, R.J. ; et al.
AIP Conf.Proc. 123 (1984) 1123-1125, 1984.
Inspire Record 201609 DOI 10.17182/hepdata.18612

The analyzing power in 28 GeV/c proton/proton elastic scattering was measured at P2∥=5.95 and 6.56 (GeV/c)2 using a polarized proton target and an unpolarized proton beam at the Brookhaven National Laboratory AGS. Results indicate that the analyzing power, A, is rising sharply with P2∥.

1 data table match query

No description provided.


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 match query

Errors quoted contain both statistical and systematic uncertainties.


Pi- p Interactions at 360-GeV/c: Measurement of the Total and Elastic Cross-Sections and the Charged Particle Multiplicity Distribution

Firestone, A. ; Anderson, E.W. ; Chang, V. ; et al.
Phys.Rev.D 14 (1976) 2902, 1976.
Inspire Record 3926 DOI 10.17182/hepdata.24670

In a sample of 108 563 pictures taken with the Fermilab 30-inch hydrogen bubble chamber, exposed to a 360-GeV/c π− beam, we have observed 19 453 interactions in a selected fiducial region. The observed charged multiplicity distribution has been corrected for the effects of scan efficiency, errors in prong count, missed close-in vees, secondary interactions, and neutron stars and for Dalitz pairs. The two-prong events have been corrected for losses at low −t. The total cross section is measured to be 25.25 ± 0.35 mb, and the elastic cross section is 3.61 ± 0.11 mb with an exponential slope of (8.82 ± 0.30) (GeV/c)−2. The average charged-particle multiplicity for inelastic events is 8.73 ± 0.04, and the second moment f2 is measured to be 9.83 ± 0.23.

2 data tables match query

SYSTEMATIC CORRECTIONS INCLUDED IN ERRORS.

FROM FIT, FORWARD D(SIG)/DT = 31.84 +- 0.68 MB/GEV**2, AND AGREES WITH OPTICAL POINT FROM MEASURED TOTAL CROSS SECTIONS.