Ballam, Joseph
nucl-ex
[1.0, 2.0]
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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
Table 1

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

Table 2

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

Table 3

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

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Differential cross section of the pion nucleon charge-exchange reaction pi- p --> pi0 n in the momentum range from 148-MeV/c to 323-MeV/c.

The Crystal Ball collaboration Sadler, M.E. ; Kulbardis, A. ; Abaev, V. ; et al.
Phys.Rev.C 69 (2004) 055206, 2004.
Inspire Record 646714 DOI 10.17182/hepdata.31725

Measured values of the differential cross section for pion-nucleon charge exchange are presented at momenta 148, 174, 188, 212, 238, 271, 298, and 323 MeV/c, a region dominated by the Delta resonance. Complete angular distributions were obtained using the Crystal Ball detector at the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL). Statistical uncertainties of the differential cross sections are typically 2-6%, exceptions being the results at the lowest momentum and at the most forward measurements of the five lowest momenta. We estimate the systematic uncertainties to be 3-6%.

3 data tables
Table 1

The errors shown are statistical only.

Table 2

The errors shown are statistical only.

Table 3

The total charge-exchange reaction cross section as a function of pion momentum obtained by integrating the differential cross sections. The errors shown are the total and statistical errors.


Measurement of K- p --> eta Lambda near threshold

The Crystal Ball collaboration Starostin, A. ; Nefkens, B.M.K. ; Berger, E. ; et al.
Phys.Rev.C 64 (2001) 055205, 2001.
Inspire Record 569202 DOI 10.17182/hepdata.25269

We present measurements of the differential and total cross sections and the Λ polarization for the reaction K−p→ηΛ from threshold to pK−=770MeV/c, with much better precision than previous measurements. Our cross-section data show a remarkable similarity to the SU(3) flavor-related π−p→ηn cross-section results. The reaction K−p→ηΛ at threshold is dominated by formation of the intermediate Λ(1670)12− state.

5 data tables
Table 1

Total cross section measurement for K- P --> ETA LAMBDA. Errors shown are statistical only.

Table 2

Differential cross sections DSIG/DOMEGA for K- P --> ETA LAMBDA. Errors shown are statistical only.

Table 3

Differential cross sections DSIG/DOMEGA for K- P --> ETA LAMBDA. Errors shown are statistical only.

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Analyzing powers for the pi- p(pol.) --> pi0 n reaction across the Delta(1232) resonance.

Gaulard, C.V. ; Riedel, C.M. ; Comfort, Joseph R. ; et al.
Phys.Rev.C 60 (1999) 024604, 1999.
Inspire Record 483795 DOI 10.17182/hepdata.51678

High quality analyzing powers for the π−p→→π0n reaction have been obtained with a polarized proton target over a broad angular range at incident kinetic energies of 98.1, 138.8, 165.9, and 214.4 MeV. This experiment nearly doubled the existing πN single-charge-exchange database for energies ranging from 10 to 230 MeV, with 36 new analyzing powers. The Neutral Meson Spectrometer was used to detect the outgoing neutral pions. The data are well described by recent phase-shift analyses. When combined with high-precision and accurate cross section data at the same energies, the data can provide a good test of the degree of isospin breaking in the region of the Δ(1232) resonance. They will also be helpful for constraining the evaluation of the pion-nucleon σ term from the scattering amplitudes.

4 data tables
Table 1

First error is total uncertainty.

Table 2

First error is total uncertainty.

Table 3

First error is total uncertainty.

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DIFFERENTIAL CROSS-SECTIONS FOR RADIATIVE CAPTURE OF PIONS ON HYDROGEN IN THE DELTA (1232) REGION: A TEST OF THE ISOSPIN STRUCTURE AND T SYMMETRY OF HADRONIC ELECTROMAGNETIC INTERACTIONS

Tran, M.T. ; Guex, L.H. ; Alder, J.C. ; et al.
Nucl.Phys.A 324 (1979) 301-334, 1979.
Inspire Record 147550 DOI 10.17182/hepdata.37080

Radiation capture of π − on hydrogen has been measured in the momentum range from p π − = 210 MeV/ c to p π − = 385 MeV/ c and for c.m. angles between 30° and 120°, covering the Δ (1232) resonance. The unambiguous separation of the events from the charge exchange background is based on precise neutron time-of-flight measurements. Detector efficiencies were carefully determined in separate experiments. The experimental results are in good agreement with those of the inverse reaction and with most recent multipole analyses. An upper limit of ±2% can be set on the contribution of the isotensor term to the transition amplitude. A time reversal violating phase, when added to the resonant M 1+ 3 amplitude in the Donnachie-Shaw model, is found to be consistent with zero.

1 data table
Table 1

This results was extracted from the cross sections for the inverse reactionPI- P --> GAMMA N via detailed balance by applying relation: D(SIG(GAMMA))/D(OM EGA)=D(SIG(PI-))/D(OMEGA)*P(PI)**2/2/P(GAMMA)**2.