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Measurement of $\Delta - \sigma_L$ in Proton Proton Scattering Between 300-{MeV} and 800-{MeV}

Auer, I.P. ; Ditzler, W.R. ; Hill, D. ; et al.
Phys.Rev.D 24 (1981) 2008, 1981.
Inspire Record 10751 DOI 10.17182/hepdata.51322

We have measured the difference between proton-proton total cross sections for parallel and antiparallel longitudinal spin states [ΔσL=σtot(⇄)−σtot(⇄)] at 13 incident energies between 300 and 800 MeV, which cover the region of possible D21 and F33 diproton resonances. The present experiment has strongly confirmed the structure previously observed at the Argonne Zero Gradient Synchrotron. No additional narrow structure has been found.

1 data table
Table 1

No description provided.


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.


Measurement of the longitudinal spin dependent neutron - proton total cross-section difference Delta sigma-L (n p) between 500-MeV - 800-MeV

Beddo, M. ; Burleson, G. ; Faucett, J.A. ; et al.
Phys.Rev.D 50 (1994) 104-123, 1994.
Inspire Record 37179 DOI 10.17182/hepdata.22460

A measurement of ΔσL(np), the difference between neutron-proton total cross sections for pure longitudinal spin states, is described. Data were taken at LAMPF for five neutron beam kinetic energies: 484, 568, 634, 720, and 788 MeV. The statistical errors are in the range of 0.64–1.35 mb. Various sources of systematic effects were investigated and are described. Overall systematic errors are estimated to be on the order of 0.5 mb and include an estimate for the uncertainty in the neutron beam polarization. The ΔσL results are consistent with previous results from PSI and Saclay. These data, when combined with other results and fitted to a Breit-Wigner curve, are consistent with an elastic I=0 resonance with mass 2214±15 (stat) ±6 (syst) MeV and width 75±21±12 MeV. Because of a lack of ΔσT(np) data between 500 and 800 MeV, it is not possible to differentiate between a singlet or coupled-triplet partial wave being responsible.

2 data tables
Table 1

No description provided.

Table 2

The (I=0) part of SIG(NAME=CLL) after subtraction of the p p data, (I=1) part.


PHOTOPRODUCTION OF pi0 WITH PLANE POLARIZED 3-Gev PHOTONS

Bellenger, D. ; Bordelon, R. ; Cohen, K. ; et al.
Phys.Rev.Lett. 23 (1969) 540, 1969.
Inspire Record 55099 DOI 10.17182/hepdata.21666

The cross section for photoproduction of π0 mesons was measured at a photon energy of 3 GeV and squared four-momentum transfer (t) of -0.1 to -1.2 (GeV/c)2 using plane-polarized photons. The asymmetry was found to be consistent with +1.0 for t values above -0.4 and below -1.1. For −0.4<~t<~−1.0 there is a dip in the asymmetry and at t=−0.6 it drops to 0.55 ± 0.15. This result precludes a simple Regge model with ω0 and B; a theoretical description requires Regge cuts or an ω′ exchange.

2 data tables
Table 1

No description provided.

Table 2

MIT PREP (1967).


Measurement of the differences in the total cross section for antiparallel and parallel longitudinal spins and a measurement of parity nonconservation with incident polarized protons and antiprotons at 200-GeV/c.

The E581/704 collaboration Grosnick, D.P. ; Hill, D.A. ; Kasprzyk, T. ; et al.
Phys.Rev.D 55 (1997) 1159-1187, 1997.
Inspire Record 420534 DOI 10.17182/hepdata.22329

The highest-energy measurement of ΔσL(pp) and the first ever measurement of ΔσL(p¯p), the differences between proton-proton and antiproton-proton total cross sections for pure longitudinal spin states, are described. Data were taken using 200-GeV/c polarized beams incident on a polarized-proton target. The results are measured to be ΔσL(pp)=−42±48(stat)±53(syst) μb and ΔσL(p¯p)=−256±124(stat)±109(syst) μb. Many tests of systematic effects were investigated and are described, and a comparison to theoretical predictions is also given. Measurements of parity nonconservation at 200 GeV/c in proton scattering and the first ever of antiproton scattering have also been derived from these data. The values are consistent with zero at the 10−5 level.

2 data tables
Table 1

No description provided.

Table 2

No description provided.


Spin transfer measurements of the pi anti-d ---> anti-p p reaction at energies spanning the Delta resonance

Feltham, A. ; Jones, G. ; Olszewski, R. ; et al.
Phys.Rev.C 55 (1997) 19-41, 1997.
Inspire Record 456889 DOI 10.17182/hepdata.25720

The first spin-transfer experiment performed for the πd→→p→p reaction is described. Three spin-transfer parameters for this π-absorption process were determined, KLSa, KSSa, and KNNa, which correspond to the π-production parameters, KSLp, KSSp, and KNNp, of the time-reversed p→p→d→π process. Each observable was measured at a single angle for a number of energies spanning the Δ resonance of this system. The results are compared with the predictions of published partial wave amplitude fits which are primarily based on existing data for the time-reversed pp→dπ reaction, and also with the predictions of two current theories. The failure of these theories to describe the fundamental features of the data clearly demonstrates the need for further theoretical work in this area.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Measurement of the anti-p p ---> anti-lambda Lambda and anti-p p ---> Antisigma0 Lambda + c.c. reactions at 1.726-GeV/c and 1.771-GeV/c

Barnes, P.D. ; Franklin, G. ; Quinn, B. ; et al.
Phys.Rev.C 54 (1996) 2831-2842, 1996.
Inspire Record 433023 DOI 10.17182/hepdata.25800

Interest in the production of hyperon-antihyperon pairs following antiproton-proton annihilation stems largely from attempts to understand the nature of flavor production. To date the major focus of both the experimental and the theoretical effort has been on the p¯p→Λ¯Λ reaction. In this paper, we present data on the complementary channels p¯p→Σ¯0Λ and p¯p→Λ¯Σ0. Events from the kinematically similar p¯p→Λ¯Λ reaction were obtained in parallel. The procedure to distinguish these three separate reactions is described and results for all channels are presented. These include the total and differential cross sections, hyperon polarizations, and spin correlation coefficients. Data were obtained at incident antiproton lab momenta of 1.726 and 1.771 GeV/c which correspond to excess kinetic energies in the p¯p→Λ¯Σ0+c.c. reaction of 26 and 40 MeV, respectively, above threshold. Comparisons are made to earlier work at similar excess energies in the p¯p→Λ¯Λ channel. The low-energy regime has been highlighted in this experiment to reduce the complexity in the theoretical analysis. © 1996 The American Physical Society.

7 data tables
Table 1

No description provided.

Table 2

Axis error includes +- 2.3/2.3 contribution.

Table 3

Axis error includes +- 2.3/2.3 contribution.

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Spin observables in elastic proton scattering from polarized He-3

Brash, E.J. ; Hausser, O. ; Cummings, W.J. ; et al.
Phys.Rev.C 52 (1995) 807-817, 1995.
Inspire Record 411136 DOI 10.17182/hepdata.25873

We have measured the absolute cross section σ(θ) and complete sets of spin observables A00ij in He3(p,p) elastic scattering at energies of 200 and 500 MeV. The observables depend on linear combinations of six complex scattering amplitudes for the p−3He system and provide a severe test of current reaction models. The in-scattering plane observables (A00mm, A00ll, A00lm, and A00ml) are all in quantitative disagreement with fully microscopic nonrelativistic optical model calculations and nonrelativistic distorted wave Born approximation calculations.

6 data tables
Table 1

A00N0 is analyzing power.

Table 2

A00N0 is analyzing power.

Table 3

A00NN is spin correlation parameter.

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Measurement of the Spin Correlation Parameters A(ll) and A(sl) for the Reaction $P P \to D \pi^+$ in the Energy Region 500-{MeV} - 800-{MeV}

Barlow, D.B. ; Saha, A. ; Seth, K.K. ; et al.
Phys.Rev.C 37 (1988) 1977-1986, 1988.
Inspire Record 242361 DOI 10.17182/hepdata.26282

Angular distributions of the spin-correlation parameters Asl and All for the reaction pp→π+d have been measured at pion center-of-mass angles 40°≤θπ+*≤130° at incident energies of 500, 650, and 800 MeV. Additional measurements of All were made at 600, 700, and 750 MeV. The results of the experiment are compared with the predictions of several unified coupled-channel calculations and partial-wave analyses. While the latest partial-wave analyses were found to fit the data reasonably well, all except one of the various model predictions not only do not fit the data well, but also tend to be in disagreement with each other. The data show no clear sign of a need for proposed dibaryon resonances.

9 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Measurements of the Double Polarization Parameters $G$ and $H$ in Neutral Pion Photoproduction

Bussey, P.J. ; Rutherglen, J.G. ; Booth, P.S.L. ; et al.
Nucl.Phys.B 159 (1979) 383-396, 1979.
Inspire Record 141663 DOI 10.17182/hepdata.34624

Measurements have been made of the double polarisation parameters G and H in the photoproduction of neutral pions from protons, for incident photon energies between 1300 MeV and 2300 MeV and for pion c.m. angles between 50δ and 80δ. The results are compared with predictions from a recent comprehensive analysis of earlier photoproduction data.

11 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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