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perimental analysis of the process is presented. Theσ(−)/σ(+) ratio has been measured in the photon energy interval (170÷230) MeV and Lab. angles 45°, 75°, 105°, 150°. The results are interpreted on the base of the impulse approximation with the aim of getting information on the processhv+n →π −+p.

6 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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Cross section measurements of charged pion photoproduction in hydrogen and deuterium from 1.1-GeV to 5.5-GeV.

The Jefferson Lab Hall A & Jefferson Lab E94-104 collaborations Zhu, L.Y. ; Arrington, J. ; Averett, T. ; et al.

Phys.Rev.C 71 (2005) 044603, 2005.

Inspire Record 659852 DOI 10.17182/hepdata.31680

The differential cross section for the gamma +n --> pi- + p and the gamma + p --> pi+ n processes were measured at Jefferson Lab. The photon energies ranged from 1.1 to 5.5 GeV, corresponding to center-of-mass energies from 1.7 to 3.4 GeV. The pion center-of-mass angles varied from 50 degree to 110 degree. The pi- and pi+ photoproduction data both exhibit a global scaling behavior at high energies and high transverse momenta, consistent with the constituent counting rule prediction and the existing pi+ data. The data suggest possible substructure of the scaling behavior, which might be oscillations around the scaling value. The data show an enhancement in the scaled cross section at center-of-mass energy near 2.2 GeV. The differential cross section ratios at high energies and high transverse momenta can be described by calculations based on one-hard-gluon-exchange diagrams.

14 data tables

Table 1

Differential cross section for the process GAMMA N --> PI- P for an incident electron energy of 5.614 GeV.

Table 2

Differential cross section for the process GAMMA N --> PI- P for an incident electron energy of 4.236 GeV.

Table 3

Differential cross section for the process GAMMA N --> PI- P for an incident electron energy of 3.400 GeV.

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DIFFERENTIAL CROSS-SECTION FOR PI- P ---> GAMMA N FROM 427-MEV/C TO 625-MEV/C

Kim, G.J. ; Arends, J. ; Briscoe, W.J. ; et al.

Phys.Rev.D 40 (1989) 244-247, 1989.

Inspire Record 285141 DOI 10.17182/hepdata.23110

Differential cross sections for π−p→γn have been determined from 427 to 625 MeV/c, mainly at 90° and 110° c.m. The data were obtained by combining measurements of the Panofsky ratio in flight with known charge-exchange cross sections. The results are compared with γn→π−p data derived from γd experiments; the difference is typically 30%. The radiative decay amplitudes of neutral πN resonances are therefore uncertain by at least 30%.

3 data tables

Table 1

Charge exchange cross section from PWA.

Table 2

PI- P --> GAMMA N cross section.

Table 3

GAMMA N --> PI- P cross section calculated using detailed balance.

PHOTOPRODUCTION OF CHARGED PIONS FROM DEUTERIUM AT GAMMA ENERGIES FROM 900-MEV TO 1800-MEV AND PION ANGLES BETWEEN 65-DEGREES AND 125-DEGREES

Besch, H.j. ; Krautschneider, F. ; Sternemann, K.p. ; et al.

Z.Phys.C 16 (1982) 1-6, 1982.

Inspire Record 184969 DOI 10.17182/hepdata.16386

π−-photoproduction cross sections from neutrons have been measured with a deuterium target at effective γ-energies from 900 to 1,800 MeV and pion centre-of-mass angles 65 to 125°. The outgoing pion and proton were detected in coincidence, the pion with a magnetic spectrometer and the proton with a time-of-flight system. To test the reliability of the analysis method, a comparison of π+-photoproduction from protons and deuterons was made with a slightly modified apparatus. It was found adequate to use the spectator model with a Huthèn wave function.

1 data table

Table 1

No description provided.

Measurement of Polarized Target Asymmetry on $\gamma n \to \pi^- p$ Around the Second Resonance Region

Fujii, K. ; Hayashii, H. ; Iwata, S. ; et al.

Nucl.Phys.B 187 (1981) 53-70, 1981.

Inspire Record 156223 DOI 10.17182/hepdata.34260

The polarized target asymmetry for γ n→ π − p was measured over the second resonance region from 0.55 to 0.9 GeV at pion c.m. angles between 60° and 120°. A double-arm spectrometer was used with a deuterated butanol target to detect both the pion and the proton, thus considerably improving the data quality. Including the new data in the amplitude analysis, the radiative decay widths of three resonances were determined more accurately than before. The results are compared with various quark models.

8 data tables

Table 1

PHOTON ENERGY IS IN THE NEUTRON REST FRAME.

Table 2

PHOTON ENERGY IS IN THE NEUTRON REST FRAME.

Table 3

PHOTON ENERGY IS IN THE NEUTRON REST FRAME.

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PHOTOPRODUCTION OF PI- MESONS ON NEUTRONS INDUCED BY POLARIZED PHOTONS IN THE ENERGY INTERVAL 0.9-GEV - 1.65-GEV. (IN RUSSIAN)

Abramian, L.O. ; Aganyants, Aleksandr O. ; Adamian, F.V. ; et al.

Yad.Fiz. 32 (1980) 133-140, 1980.

Inspire Record 159786 DOI 10.17182/hepdata.18933

None

6 data tables

Table 1

Axis error includes +- 10./10. contribution (DUE TO BEAM POLARIZATION UNCERTAINTY).

Table 2

D(SIG)/D(OMEGA)=(D(SIG(O))/D(OMEGA)+D(SIG(C))/D(OMEGA))/2, WHERE (O) AND (C) DENOTES GAMMA POLARIZATION ORTHOGONAL AND COPLANAR TO THE REACTION PLANE.

Table 3

Axis error includes +- 10./10. contribution (DUE TO BEAM POLARIZATION UNCERTAINTY).

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Measurement of Recoil Proton Polarization in the Process of $\pi^-$ Photoproduction From Neutrons in the Energy Range Between 700-{MeV} and 1200-{MeV}

Takeda, H. ; Arai, I. ; Fujii, T. ; et al.

Nucl.Phys.B 168 (1980) 17-31, 1980.

Inspire Record 131380 DOI 10.17182/hepdata.34512

The recoil proton polarization for γ n → π − p was measured around the third resonance region. Both momentum vectors of the proton and the pion were determined by the magnetic spectrometers. The proton polarization was measured by means of proton-carbon scattering in the polarization analyzer located behind the proton spectrometer. Below 900 MeV incident photon energy, our data are consistent with the other existing experimental data ( θ π ∗ = 90° ) and the predictions of partial-wave analyses. Above 1000 MeV, however, a large discrepancy was observed between our data and the predictions of the partial-wave analyses. The discrepancy stands out as the pion c.m. angle increases. A new partial-wave analysis was made for γ n → π − p including our polarization data, and the accuracy of the experimentally determined electromagnetic coupling constant of the third resonances were greatly improved. In particular, a finite amount of the helicity 3 2 amplitude for the γ n → F 15 (1688) resonance was obtained against the predictions of the quark models, by Copley, Karl and Obryk and by Feynman, Kislinger and Ravendal but in agreement with the relativistic quark models of Sugimoto and Toya, and Kubota and Ohta.

1 data table

Table 1

No description provided.

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Total cross-section measurement of $\pi^{-}$ photoproduction on deuteron in the first-resonance region.

Photoproduction of charged pions near threshold

Determination of the γ - π - ρ coupling constant from the −/+ ratio for photoproduction from deuterium

Photoproduction of charged pions in deuterium

Cross section measurements of charged pion photoproduction in hydrogen and deuterium from 1.1-GeV to 5.5-GeV.

DIFFERENTIAL CROSS-SECTION FOR PI- P ---> GAMMA N FROM 427-MEV/C TO 625-MEV/C

PHOTOPRODUCTION OF CHARGED PIONS FROM DEUTERIUM AT GAMMA ENERGIES FROM 900-MEV TO 1800-MEV AND PION ANGLES BETWEEN 65-DEGREES AND 125-DEGREES

Measurement of Polarized Target Asymmetry on $\gamma n \to \pi^- p$ Around the Second Resonance Region

PHOTOPRODUCTION OF PI- MESONS ON NEUTRONS INDUCED BY POLARIZED PHOTONS IN THE ENERGY INTERVAL 0.9-GEV - 1.65-GEV. (IN RUSSIAN)

Measurement of Recoil Proton Polarization in the Process of $\pi^-$ Photoproduction From Neutrons in the Energy Range Between 700-{MeV} and 1200-{MeV}