$\pi$-proton scattering at 516, 616, 710, 887, and 1085 MeV

Gbaed, F. ; Montanet, L. ; Lehmann, P. ; et al.
Nuovo Cim. 22 (1961) 193-198, 1961.
Inspire Record 1187691 DOI 10.17182/hepdata.37734

We present results on .~--p seattering at kinetic energies in the laboratory of 516, 616, 710, 887 and 1085MeV. The data were obtained by exposing a liquid hydrogen bubble chamber to a pion beam from the Saelay proton synchrotron Saturne. The chamber had a diameter of 20 cm and a depth of 10 cm. There was no magnetic field. Two cameras, 15 em apart, were situated at 84 cm from the center- of the chamber. A triple quadrnpole lens looking at an internal target, and a bending magnet, defined the beam, whose momentum spread was less than 2%. The value of the momentum was measured by the wire-orbit method and by time of flight technique, and the computed momentum spread was checked by means of a Cerenkov counter. The pictures were scanned twice for all pion interactions. 0nly those events with primaries at most 3 ~ off from the mean beam direction and with vertices inside a well defined fiducial volume, were considered. All not obviously inelastic events were measured and computed by means of a Mercury Ferranti computer. The elasticity of the event was established by eoplanarity and angular correlation of the outgoing tracks. We checked that no bias was introduced for elastic events with dip angles for the scattering plane of less than 80 ~ and with cosines of the scattering angles in the C.M.S. of less than 0.95. Figs. 1 to 5 show the angular distributions for elastic scattering, for all events with dip angles for the scattering plane less than 80 ~ . The solid curves represent a best fit to the differential cross section. The ratio of charged inelastic to elastic events, was obtained by comparing the number of inelastic scatterings to the areas under the solid curves which give the number of elastic seatterings.

5 data tables

No description provided.

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Measures of the differential effective sections $\pi ±p$ to 410 MeV and 490 MeV forwards

Banner, M. ; Detoeuf, J.F. ; Fayoux, M.L. ; et al.
Nuovo Cim.A 50 (1967) 431-448, 1967.
Inspire Record 1185325 DOI 10.17182/hepdata.896

Measurements of π±p elastic differential cross-sections have been performed in the forward direction, using a missing-mass spark chamber spectrometer. The films have been seanned by an automatic apparatus. A phase-shift analysis of the experimental data has been done, leading to three solutions. Various experiments are proposed in order to resolve the ambiguities.

4 data tables

No description provided.

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pi+- p differential cross sections at low energies.

Denz, H. ; Amaudruz, P. ; Brack, J.T. ; et al.
Phys.Lett.B 633 (2006) 209-213, 2006.
Inspire Record 699647 DOI 10.17182/hepdata.31620

Differential cross sections for pi- p and pi+ p elastic scattering were measured at five energies between 19.9 and 43.3 MeV. The use of the CHAOS magnetic spectrometer at TRIUMF, supplemented by a range telescope for muon background suppression, provided simultaneous coverage of a large part of the full angular range, thus allowing very precise relative cross section measurements. The absolute normalisation was determined with a typical accuracy of 5 %. This was verified in a simultaneous measurement of muon proton elastic scattering. The measured cross sections show some deviations from phase shift analysis predictions, in particular at large angles and low energies. From the new data we determine the real part of the isospin forward scattering amplitude.

12 data tables

Elastic PI- P cross section for incident kinetic energy 43.3 MeV for the rotated target data. Errors shown are statistical only.

Elastic PI- P cross section for incident kinetic energy 43.3 MeV. Errors shown are statistical only.

Elastic PI- P cross section for incident kinetic energy 37.1 MeV. Errors shown are statistical only.

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Low energy analyzing powers in pion proton elastic scattering.

Meier, R. ; Croni, M. ; Bilger, R. ; et al.
Phys.Lett.B 588 (2004) 155-162, 2004.
Inspire Record 645151 DOI 10.17182/hepdata.26962

Analyzing powers of pion-proton elastic scattering have been measured at PSI with the Low Energy Pion Spectrometer LEPS as well as a novel polarized scintillator target. Angular distributions between 40 and 120 deg (c.m.) were taken at 45.2, 51.2, 57.2, 68.5, 77.2, and 87.2 MeV incoming pion kinetic energy for pi+ p scattering, and at 67.3 and 87.2 MeV for pi- p scattering. These new measurements constitute a substantial extension of the polarization data base at low energies. Predictions from phase shift analyses are compared with the experimental results, and deviations are observed at low energies.

11 data tables

Analyzing power for PI+ P elastic scattering at incidient kinetic energy 87.2 MeV from the data set 1.

Analyzing power for PI+ P elastic scattering at incidient kinetic energy 68.4 MeV from the data set 1.

Analyzing power for PI+ P elastic scattering at incidient kinetic energy 57.2 MeV from the data set 1.

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Analyzing powers for pi- p elastic scattering at 279-MeV

Hofman, G.J. ; Craig, K. ; Pavan, M.M. ; et al.
Phys.Rev.C 68 (2003) 018202, 2003.
Inspire Record 628373 DOI 10.17182/hepdata.25270

Analyzing powers for π−p elastic scattering have been measured at TRIUMF using the CHAOS spectrometer and a spin-polarized target. These data were collected at a bombarding energy of Tπ=279MeV and cover an angular range of 53<~θc.m.π<~180°. There is good agreement between these data and the latest partial wave analysis from the VPI/GWU group.

1 data table

Analysing power measurement.


Analyzing powers for pi p elastic scattering between 57 and 139 MeV

Patterson, J.D. ; Hofman, G.J. ; Brack, J.T. ; et al.
Phys.Rev.C 66 (2002) 025207, 2002.
Inspire Record 594648 DOI 10.17182/hepdata.25268

Analyzing powers for πp elastic scattering at bombarding energies below the Δ(1232) resonance were measured at TRIUMF using the CHAOS spectrometer and a polarized spin target. This work presents π− data at six incident energies of 57, 67, 87, 98, 117, and 139 MeV, and a single π+ data set at 139 MeV. The higher energy measurements cover an angular range of 72°<~θc.m.<~180° while the lower energies were limited to 101°<~θc.m.<~180°. There is a high degree of consistency between this work and the predictions of the VPI/GWU group’s SM95 partial wave analysis.

9 data tables

Analysing power measurements for a 139 GeV PI+ beam (standard track).

Analysing power measurements for a 139 GeV PI- beam (standard track).

Analysing power measurements for a 117 GeV PI- beam (standard track).

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Precision pion proton elastic differential cross sections at energies spanning the Delta resonance.

Pavan, M.M. ; Brack, J.T. ; Duncan, F. ; et al.
Phys.Rev.C 64 (2001) 064611, 2001.
Inspire Record 554203 DOI 10.17182/hepdata.31782

A precision measurement of absolute pi+p and pi-p elastic differential cross sections at incident pion laboratory kinetic energies from T_pi= 141.15 to 267.3 MeV is described. Data were obtained detecting the scattered pion and recoil proton in coincidence at 12 laboratory pion angles from 55 to 155 degrees for pi+p, and six angles from 60 to 155 degrees for pi-p. Single arm measurements were also obtained for pi+p energies up to 218.1 MeV, with the scattered pi+ detected at six angles from 20 to 70 degrees. A flat-walled, super-cooled liquid hydrogen target as well as solid CH2 targets were used. The data are characterized by small uncertainties, ~1-2% statistical and ~1-1.5% normalization. The reliability of the cross section results was ensured by carrying out the measurements under a variety of experimental conditions to identify and quantify the sources of instrumental uncertainty. Our lowest and highest energy data are consistent with overlapping results from TRIUMF and LAMPF. In general, the Virginia Polytechnic Institute SM95 partial wave analysis solution describes our data well, but the older Karlsruhe-Helsinki PWA solution KH80 does not.

18 data tables

Centre of mass absolute differential cross sections at pion kinetic energy 141.15 MeV using the liquid H2 target and single arm pion detection. There is an additional systematic error of 1.1 PCT for PI+ beams which is not included in the errors shown in the table.

Centre of mass absolute differential cross sections at pion kinetic energy 141.15 MeV using the liquid H2 target and two arm pion detection. There is an additional systematic error of 1.3 PCT for PI+ beams which is not included in the errors shown in the table.

Centre of mass absolute differential cross sections at pion kinetic energy 141.15 MeV using the liquid H2 target and two arm pion detection. There is an additional systematic error of 1.3 PCT (1.6 PCT) for PI+ (PI-) beams which is not included in the errors shown in the table.

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Analyzing powers for pi+- p(pol.) elastic scattering between 87-MeV and 263-MeV.

Hofman, G.J. ; Smith, G.R. ; Ambardar, T. ; et al.
Phys.Rev.C 58 (1998) 3484-3493, 1998.
Inspire Record 483008 DOI 10.17182/hepdata.25722

Analyzing powers for πp elastic scattering were measured using the CHAOS spectrometer at energies spanning the Δ(1232) resonance. This work presents π+ data at the pion kinetic energies 117, 130, 139, 155, 169, 180, 193, 218, 241, and 267 MeV and π− data at 87, 117, 193, and 241 MeV, covering an angular range of 50°<~θc.m.<~180° at the higher energies and 90°<~θc.m.<~180° at the lower energies. Unique features of the spectrometer acceptance were employed to reduce systematic errors. Single-energy phase shift analyses indicate the resulting S11 and S31 phases favor the results of the SM95 phase shift analysis over that of the older KH80 analysis.

18 data tables

Measurement of the PI+ analysing power at 117 MeV.. The data were collected in the conventional mode and may be independently floated within the systematic error.

Measurement of the PI+ analysing power at 139 MeV.. The data were collected in the conventional mode and may be independently floated within the systematic error.

Measurement of the PI- analysing power at 87 MeV.. The data were collected in the conventional mode and may be independently floated within the systematic error.

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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

No description provided.


Comparison of Exclusive Reactions at Large $T$

Baller, B.R. ; Blazey, G.C. ; Courant, H. ; et al.
Phys.Rev.Lett. 60 (1988) 1118-1121, 1988.
Inspire Record 264273 DOI 10.17182/hepdata.3063

Cross sections or upper limits are reported for 12 meson-baryon and two baryon-baryon reactions for an incident momentum of 9.9 GeV/c, near 90° c.m.: π±p→pπ±,pp±,π+°±,K+Σ±, (Λ0/Σ0)K0; K±p→pK±; p±p→pp. By studying the flavor dependence of the different reactions, we have been able to isolate the quark-interchange mechanism as dominant over gluon exchange and quark-antiquark annihilation.

2 data tables

No description provided.

No description provided.