Niehaus, W.
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$\pi^{-} + p$ elastic scattering in the neighbourhood of $N^{*}_1/2$ (2190)

Busza, W. ; Davis, D.G. ; Duff, B.G. ; et al.
Nuovo Cim.A 52 (1967) 331-341, 1967.
Inspire Record 1185326 DOI 10.17182/hepdata.37568

Elastic π−+p differential cross-section data are presented at the incident-pion momenta 1.72, 1.89, 2.07, 2.27 and 2.46 GeV/c. Resonant behaviour in the coefficients of a Legendre polynomial expansion indicates G- or H-wave resonance. Further analysis using an energy-dependent parametrization of G- and H-waves shows the results to be compatible with the 7−/2 assignment for the , but equally acceptable solutions are obtained with the inclusion of an additional 9+/2 resonance contribution.

5 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Hidden Strangeness in the Proton? Determination of the Real Part of the Isospin Even - Forward Scattering Amplitude of Pion Nucleon Scattering at 54.3-{MeV}

Wiedner, U. ; Goring, K. ; Jaki, J. ; et al.
Phys.Rev.D 40 (1989) 3568-3581, 1989.
Inspire Record 287810 DOI 10.17182/hepdata.23079

The contradiction of the σ term of pion-nucleon scattering as deduced from the Karlsruhe-Helsinki phase shifts with the smaller value calculated by the chiral perturbation theory of QCD is well known. In an effort to clarify the discrepancy we have determined the real part of the isospin-even forward-scattering amplitude of pion-nucleon scattering at a pion energy Tπ=54.3 MeV by measurement of the elastic scattering of positive and negative pions on protons in the Coulomb-nuclear interference region. The deduced value is in agreement with the prediction of the Karlsruhe-Helsinki phase-shift analysis for that energy. The resulting large value of the σ term may be interpreted as being due to the influence of s¯s sea pairs even at large distances (small Q2) as previously suggested by the European Muon Collaboration measurement of deep-inelastic scattering of polarized muons on polarized protons.

1 data table
Table 1

No description provided.


Determination of the Real Part of the Isospin Even Forward Scattering Amplitude of Pion Nucleon Scattering at 55-{MeV} as a Test of Low-energy Quantum Chromodynamics

Wiedner, U. ; Goring, K. ; Jaki, J. ; et al.
Phys.Rev.Lett. 58 (1987) 648-650, 1987.
Inspire Record 246624 DOI 10.17182/hepdata.20153

The real part of the isospin-even forward-scattering amplitude of pion-nucleon scattering has been determined at a pion energy of Tπ=55 MeV by measurement of the elastic scattering of positive and negative pions on protons within the Coulomb-nuclear interference region. The value confirms the prediction of the Karlsruhe-Helsinki phase-shift analysis for that energy. These phases have been used to determine the σ term of pion-nucleon scattering by means of dispersion relations, resulting in a value for σ which is in contradiction with chiral perturbation theory of QCD.

1 data table
Table 1

PI- P cross sections normalised to the Coulomb cross section taken from the Karlesruhe-Helsinki phase shift analysis (R. Koch, E. Pietarinen (NP A336(80)331).


Operation and Performance of a System for $\pi p$ and $\pi D$ Backward Scattering

Stanovnik, A. ; Kernel, G. ; Tanner, N.W. ; et al.
Nucl.Instrum.Meth. 177 (1980) 369, 1980.
Inspire Record 152948 DOI 10.17182/hepdata.41451

A simple, large-solid-angle apparatus, specially suited for the measurement of backward elastic scattering of medium-energy pions on protons and deuterons, is described. The method of analysis which reduces background and determines elastic events from a data sample of 185 MeV negative pions incident on a D 2 O target is discussed. Results for 141 MeV π + p and 185 MeV π − p backward cross-sections are also presented and compared with cross-sections calculated from known phase shifts.

2 data tables

POLARIZATION PARAMETERS AND ANGULAR DISTRIBUTIONS IN PI+- P ELASTIC SCATTERING AT 100-GEV/C AND IN P P ELASTIC SCATTERING AT 100-GEV/C AND 300-GEV/C

Kline, R.V. ; Law, M.E. ; Pipkin, F.M. ; et al.
Phys.Rev.D 22 (1980) 553-572, 1980.
Inspire Record 158989 DOI 10.17182/hepdata.24156

Measurements of the polarization parameters and angular distributions are reported for π±p elastic scattering at 100 GeV/c and for pp elastic scattering at 100- and 300-GeV/c incident momentum. The π±p data cover the kinematic range 0.18≤−t≤1.10 GeV2 and are in agreement with current Regge-model predictions. The pp data cover the kinematic range 0.15≤−t≤1.10 GeV2 and 0.15≤−t≤2.00 GeV2 at 100 and 300 GeV/c, respectively, and are found to be consistent with absorption-model predictions.

2 data tables
Table 1

THESE ANGULAR DISTRIBUTIONS AND POLARIZATION PARAMETERS ARE TABULATED IN THE RECORD OF THE EARLIER BRIEF REPORT OF THIS EXPERIMENT USING PION BEAMS: I. P. AUER ET AL., PRL 39, 313 (1977).

Table 2

THESE ANGULAR DISTRIBUTIONS AND POLARIZATION PARAMETERS ARE TABULATED IN THE RECORD OF THE EARLIER BRIEF REPORT OF THIS EXPERIMENT USING A PROTON BEAM: J. H. SNYDER ET AL., PRL 41, 781 (1978) AND PRL 41, 1256(E) (1978).


Meson Production by Delta Exchange in pi- p Interactions at 4-GeV/c

Scharre, D.L. ; Chapman, J.W. ; Ely, R.P. ; et al.
Phys.Rev.D 17 (1978) 2853, 1978.
Inspire Record 121388 DOI 10.17182/hepdata.24432

A streamer-chamber spectrometer is triggered by fast forward protons from 4-GeV/c π−p interactions at the Bevatron. Meson-resonance production in the backward, Iu=32 exchange reactions π−p→pM− are studied, where M− refers to π−, ρ−, A1−, A2−, and B−. Elastic scattering and ρ− production are observed and discussed in detail. No backward A1−, A2−, or B− production is observed at the level of approximately 5 βb.

5 data tables
Table 1

Axis error includes +- 15/15 contribution.

Table 2

No description provided.

Table 3

Axis error includes +- 15/15 contribution.

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Measurement of the $\pi^+ p$ and $\pi^- p$ Polarization Parameters at 100 GeV/c

Auer, I.P. ; Hill, D. ; Sandler, B. ; et al.
Phys.Rev.Lett. 39 (1977) 313, 1977.
Inspire Record 121138 DOI 10.17182/hepdata.20982

We report measurements of the polarization parameters in π+p and π−p elastic scattering at an incident momentum of 100 GeV/c. The results cover the range 0.18<~−t<~1.4 GeV2 and are in agreement with current Regge-model predictions.

3 data tables
Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.


Polarization in pi- p Elastic Scattering at 1180-MeV/c, 1250-MeV/c, and 1360-MeV/c

Barrelet, E. ; Chamberlain, O. ; Gorn, W. ; et al.
Phys.Rev.D 15 (1977) 2435, 1977.
Inspire Record 110059 DOI 10.17182/hepdata.24619

We have measured the polarization parameter in π−p elastic scattering at laboratory momenta of 1180, 1250, and 1360 MeV/c in the angular interval 65°<θc.m.<115°. The results were used to show that the polarized target used in these (and other similar) experiments was uniformly polarized. These measurements were also used to resolve pre-existing experimental discrepancies in the determination of the polarization parameter, and to clarify the behavior of scattering amplitudes in this energy range. We show that local measurements of this type are important in resolving discrete ambiguities affecting the energy continuation of the amplitudes. An important by-product of this experiment is the development of a fast method of reconstructing particle trajectories and fitting the elastic events, which could have a significant impact for future high-statistics experiments.

1 data table
Table 1

No description provided.


Cross-Sections and Charged Multiplicity Distributions for $\pi^- p$ and $K^- p$ Interactions at 147 GeV/c.

Fong, D. ; Heller, M. ; Shapiro, A.M. ; et al.
Nucl.Phys.B 102 (1976) 386-404, 1976.
Inspire Record 112604 DOI 10.17182/hepdata.36057

The results presented in this paper were obtained from a 105 000 frame exposure of the FNAL Hybrid Proportional Wire Chamber-30 inch Bubble Chamber System, in a tagged beam of 147 GeV/ c negative particles. Elastic, total and topological cross sections were obtained for both π − p and K − p interactions. Comparisons with other data, taken with various beam particles over large momentum intervals, show good agreement with KNO scaling, and similarity in the scaling behavior of σ n for the different beam particles.

3 data tables
Table 1

THESE CROSS SECTIONS ARE NOT NORMALIZED TO ANY OTHER ABSOLUTE MEASUREMENT. THE ERRORS INCLUDE SOME SYSTEMATIC ERRORS.

Table 2

THE FORWARD CROSS SECTION AGREES WELL WITH THE OPTICAL POINT FROM TOTAL CROSS SECTION MEASUREMENTS.

Table 3

THESE CROSS SECTIONS ARE NOT NORMALIZED TO ANY OTHER ABSOLUTE MEASUREMENT.


Inelastic Two Prong Events in 147-GeV/c $\pi^- p$ Collisions.

Fong, D. ; Heller, M. ; Shapiro, A. ; et al.
Nucl.Phys.B 104 (1976) 32-51, 1976.
Inspire Record 112609 DOI 10.17182/hepdata.36026

None

1 data table
Table 1

No description provided.