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The total cross sections for pionic charge exchange on hydrogen were measured using a transmission technique on thin CH2 and C targets. Data were taken for pi- lab energies from 39 to 247 MeV with total errors of typically 2% over the Delta-resonance and up to 10% at the lowest energies. Deviations from the predictions of the SAID phase shift analysis in the 60 to 80 MeV region are interpreted as evidence for isospin-symmetry breaking in the s-wave amplitudes. The charge dependence of the Delta-resonance properties appears to be smaller than previously reported.

1 data table

Table 1

Measured total charge exchange cross sections. The errors are the combined statistical and ststematic errors including normalisation uncertainties.

Measurement of pi- p ---> pi0 n in the vicinity of the eta threshold

Starostin, A. ; Prakhov, S. ; Nefkens, B.M.K. ; et al.

Phys.Rev.C 72 (2005) 015205, 2005.

Inspire Record 688197 DOI 10.17182/hepdata.25171

We report a new measurement of the differential cross section for π−p→π0n from pπ=649 to 752 MeV/c, which is around the opening of the η channel (685 MeV/c). Our data support the main features of the π−p charge-exchange differential cross sections generated by the SAID πN partial-wave analysis. The opening of the η channel has a clear effect on the shape of the excitation function for dσ(π−p→π0n), which is most noticeable in the backward direction.

9 data tables

Table 1

Differential cross section for incident pion momentum 649, 654 and 657 MeV.

Table 2

Differential cross section for incident pion momentum 661, 666 and 669 MeV.

Table 3

Differential cross section for incident pion momentum 673, 678 and 681 MeV.

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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.

Integral cross-sections for pi- p interaction in the 3,3 resonance region

Friedman, E. ; Paul, M. ; Schechter, M. ; et al.

Phys.Lett.B 302 (1993) 18-22, 1993.

Inspire Record 362059 DOI 10.17182/hepdata.28945

Total cross sections for the π − p single charge exchange and 20° “partial-total” cross sections have been measured between 126 and 202 MeV pion energy. The former are about 4% below similar results of Bugg et al. and (5–10)% below predictions made with currently accepted phase shifts. The latter agree quite well with calculations.

1 data table

Table 1

No description provided.

Analyzing power for pi- p charge exchange in the backward hemisphere from 301-MeV/c to 625-MeV/c and a test of pi N partial wave analyses

Kim, G.J. ; Arends, J. ; Engelage, J. ; et al.

Phys.Rev.D 41 (1990) 733-743, 1990.

Inspire Record 301242 DOI 10.17182/hepdata.22935

The analyzing power of π−p→π0n has been measured for pπ=301−625 MeV/c with a transversely polarized target, mainly in the backward hemisphere. The final-state neutron and a γ from the π0 were detected in coincidence with two counter arrays. Our results are compared with predictions of recent πN partial-wave analyses by the groups of Karlsruhe-Helsinki, Carnegie-Mellon University-Lawrence Berkeley Laboratory (CMU-LBL), and Virginia Polytechnic Institute (VPI). At the lower incident energies little difference is seen among the three analyses, and there is excellent agreement with our data. At 547 MeV/c and above, our data strongly favor the VPI phases, and disagree with Karlsruhe-Helsinki and CMU-LBL analyses, which are the source of the πN resonance parameters given in the Particle Data Group table.

7 data tables

Table 1

Axis error includes +- 5/5 contribution (Uncertainty in background normalisation).

Table 2

Axis error includes +- 5/5 contribution (Uncertainty in background normalisation).

Table 3

Axis error includes +- 5/5 contribution (Uncertainty in background normalisation).

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CROSS-SECTIONS FOR PI- + P ---> N + (K) PI0 (K = 1 TO 5) AND PI- + P ---> N + ETA0 (ETA0 ---> 2 GAMMA) FOR INCIDENT PION MOMENTA BETWEEN 1.3-GEV/C AND 3.8-GEV/C

Crouch, H.R. ; Hargraves, R. ; Lanou, R.E. ; et al.

Phys.Rev.D 21 (1980) 3023-3058, 1980.

Inspire Record 158169 DOI 10.17182/hepdata.4334

This paper presents the results of a study of the dominant neutral final states from π−p interactions. The data were obtained in an experiment performed at the Brookhaven National Laboratory Alternating Gradient Synchrotron, using a set of steel-plate optical spark chambers surrounding a liquid-hydrogen target. We present differential and total cross sections for the reactions (1) π−p→n+π0 and (2) π−p→n+η0(η0→2γ) and total cross sections for the reactions (3) π−p→n+kπ0 (k=2, 3, 4, and 5) and (4) π−p→all neutrals for eighteen values of beam momentum in the interval 1.3 to 4.0 GeV/c. The angular distributions for (1) and (2) have been analyzed in terms of expansions in Legendre polynomials, the coefficients for which are also given.

41 data tables

Table 1

No description provided.

Table 2

SIG = 4*PI*LEG(L=0).

Table 3

FORWARD DIFFERENTIAL CROSS SECTION CALCULATED FROM LEGENDRE POLYNOMIAL COEFFICIENTS AND ERROR MATRICES.

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Polarization Measurements in $\pi^- p$ Charge Exchange Scattering From 617-{MeV}/$c$ to 2267-{MeV}/$c$

Brown, Robert M. ; Clark, A.G. ; Davies, J.K. ; et al.

Nucl.Phys.B 144 (1978) 287-311, 1978.

Inspire Record 130405 DOI 10.17182/hepdata.8173

Results are presented of polarization parameter measurements for the reaction π − p→ π 0 n at 22 momenta between 617 and 2267 MeV/ c . These results are generally in agreement with those of previous measurements and in qualitative agreement with predictions of phase-shift analyses. Together with the recently published differential cross-section measurements, they provide a comprehensive set of data for this reaction in the resonance region.

22 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Differential Cross-Section Measurements in $\pi^{-}$p Charge Exchange Scattering from 620 to 2730-MeV/c

Brown, Robert M. ; Clark, A.G. ; Davies, J.K. ; et al.

Nucl.Phys.B 117 (1976) 12-49, 1976.

Inspire Record 110001 DOI 10.17182/hepdata.8341

Results are presented of differential cross-section measurements for the reaction π − p→ π 0 n; π 0 → γγ at 22 incident pion momenta between 618 and 2724 MeV/ c . The results are in good agreement with those of other experiments. They represent the first comprehensive set of high statistics measurements of the π − p charge-exchange differential cross section at closely spaced momenta in the resonance region.

31 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.