Cross Section for $\gamma n \to \pi^0 n$ measured at Mainz/A2

The A2 collaboration Briscoe, W.J. ; Hadžimehmedović, M. ; Kudryavtsev, A.E. ; et al.
Phys.Rev.C 100 (2019) 065205, 2019.
Inspire Record 1748263 DOI 10.17182/hepdata.116236

The $\gamma n \to \pi^0 n$ differential cross section evaluated for 27 energy bins span the photon-energy range 290-813 MeV (W = 1.195-1.553 GeV) and the pion c.m. polar production angles, ranging from 18 deg to 162 deg, making use of model-dependent nuclear corrections to extract pi0 production data on the neutron from measurements on the deuteron target. Additionally, the total photoabsorption cross section was measured. The tagged photon beam produced by the 883-MeV electron beam of the Mainz Microtron MAMI was used for the 0-meson production. Our accumulation of 3.6 x 10^6 $\gamma n \to \pi^0 n$ events allowed a detailed study of the reaction dynamics. Our data are in reasonable agreement with previous A2 measurements and extend them to lower energies. The data are compared to predictions of previous SAID, MAID, and BnGa partial-wave analyses and to the latest SAID fit MA19 that included our data. Selected photon decay amplitudes $N^* \to \gamma n$ at the resonance poles are determined for the first time.

21 data tables

Excitation function at pion c.m. angle THETA=18 deg as function of incident photon energy E. The uncertainties are statistical and systematic, combined in quadrature.

Excitation function at pion c.m. angle THETA=32 deg as function of incident photon energy E. The uncertainties are statistical and systematic, combined in quadrature.

Excitation function at pion c.m. angle THETA=41 deg as function of incident photon energy E. The uncertainties are statistical and systematic, combined in quadrature.

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Reanalysis of Rosenbluth measurements of the proton form factors

Gramolin, A.V. ; Nikolenko, D.M. ;
Phys.Rev.C 93 (2016) 055201, 2016.
Inspire Record 1431987 DOI 10.17182/hepdata.77063

We present a reanalysis of the data from Stanford Linear Accelerator Center (SLAC) experiments E140 [R. C. Walker et al., Phys. Rev. D 49, 5671 (1994)] and NE11 [L. Andivahis et al., Phys. Rev. D 50, 5491 (1994)] on elastic electron-proton scattering. This work is motivated by recent progress in calculating the corresponding radiative corrections and by the apparent discrepancy between the Rosenbluth and polarization transfer measurements of the proton electromagnetic form factors. New, corrected values for the scattering cross sections are presented, as well as a new form factor fit in the $Q^2$ range from 1 to 8.83 $\text{GeV}^2$. We also provide a complete set of revised formulas to account for radiative corrections in single-arm measurements of unpolarized elastic electron-proton scattering.

3 data tables

Radiative corrections and differential cross sections obtained by reanalysis of the measurements.

Radiative corrections and differential cross sections obtained by reanalysis of the measurements.

Radiative corrections and differential cross sections obtained by reanalysis of the measurements.


REACTION OF QUASIELASTIC CHARGE EXCHANGE P HE-3 ---> N(F) P P P AT MEDIUM-ENERGIES. (IN RUSSIAN)

Blinov, A.V. ; Vanyushin, I.A. ; Grechko, V.E. ; et al.
Sov.J.Nucl.Phys. 47 (1988) 594, 1988.
Inspire Record 253277 DOI 10.17182/hepdata.9993

None

8 data tables

N IS FAST IN LABORATORY SYSTEM. CUT FOR 'FAST' SELECTION WAS:. PLAB(P=3) > PMIN(P=3), WHERE PMIN IS DETERMINED FROM ALL EVENTS.

N IS FAST IN LABORATORY SYSTEM. CUT FOR 'FAST' SELECTION WAS:. PLAB(P=3) > PMIN(P=4,5,6), WHERE PMIN IS DETERMINED FROM ALL EVENTS.

No description provided.

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DIFFERENTIAL CROSS-SECTIONS FOR pi PRODUCTION AT THETA (pi) = 60-degrees in 1-GeV PROTON INTERACTION WITH NUCLEI

Abaev, V.V. ; Gridnev, A.B. ; Koptev, V.P. ; et al.
LENINGRAD-84-1009, 1984.
Inspire Record 210113 DOI 10.17182/hepdata.9418

None

4 data tables

No description provided.

No description provided.

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Investigation of energy spectra of Z=1 and 2 particles from deuteron reactions on $^{58}$Ni, $^{64}$Ni nuclei

Kondrat'ev, V.P. ; Krasnov, L.V. ; Litvin, V.F. ; et al.
JINR-1-84-778, 1984.
Inspire Record 1387707 DOI 10.17182/hepdata.1113

The experimental energy, angular and isotopic distributions for hydrogen and helium nuclei produced in 6.7 GeV deuteron interactions with 58Ni and 64Ni isotopes are presented. The data obtained by using the multichannel E-E semiconductor spectrometer in the 3-50 MeV energy range. Energy spectra are very close to Maxwell distribution, angular distributions are isotropic, isotopic ratios do not depend on emission angle of fragments but depend on a projectile mass

3 data tables

No description provided.

No description provided.

No description provided.


Measurement of small angle elastic scattering of pions and protons by nuclei

Blieden, H.R. ; Finocchiaro, G. ; Goldhaber, A.S. ; et al.
Phys.Rev.D 11 (1975) 14, 1975.
Inspire Record 90186 DOI 10.17182/hepdata.4892

Targets made of C, Al, Cu, Pb, and U were exposed to π+, π−, and proton beams of 9.92 and 19.85 GeV/c (for p-Pb only) at the Brookhaven AGS. A magnetic spectrometer with spark chambers was used to detect elastically scattered particles in the Coulomb-nuclear interference region (5-35 mrad). Differential cross sections are presented and compared with an optical model, taking full account of multiple scattering in the target.

15 data tables

X ERROR TARG.THICKN. = 0.10 RAD.LENGTH. X ERROR D(THETA) = 0.3000 MRAD.

X ERROR TARG.THICKN. = 0.10 RAD.LENGTH. X ERROR D(THETA) = 0.3000 MRAD.

X ERROR TARG.THICKN. = 0.10 RAD.LENGTH. X ERROR D(THETA) = 0.3000 MRAD.

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The yields of particles of 1 and 2 charges from proton interactions on $^{58}Ni$ and $^{64}Ni$ targets at 7.54 GeV energy

Krasnov, L.V. ; Lakomkin, Yu.A. ; Litvin, V.F. ; et al.
JINR-1-84-225, 2016.
Inspire Record 1501543 DOI 10.17182/hepdata.76287

None

11 data tables

Axis error includes +- 20/20 contribution.

Axis error includes +- 20/20 contribution.

Axis error includes +- 20/20 contribution.

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K- p Cross-Sections Between 1.1-GeV/c and 1.4-GeV/c

Griselin, J. ; Givernaud, A. ; Barloutaud, R. ; et al.
Nucl.Phys.B 93 (1975) 189-216, 1975.
Inspire Record 99412 DOI 10.17182/hepdata.6708

K − p reactions have been studied at 13 different incident momenta between 1138 and 1434 MeV/ c . This interval corresponds to a mass of the K − p system varying from 1858 to 1993 MeV. About 300 000 photographs were taken in the 81 cm Saclay hydrogen bubble chamber exposed to a separated K − beam at the CERN proton-synchrotron. A total of about 44 000 events were analyzed, from which partial and differential cross sections were determined. Polarizations were obtained for the two-body reactions where the decay of the Λ or Σ hyperon allowed their measurement. Data for the two-body channels are presented here as well as for the main quasi-two-body reactions.

9 data tables

PARTIAL CROSS SECTIONS. DATA AT 1.305 TO 1.434 GEV/C FOR FINAL STATES K- P, K- P PI0 AND K- N PI+ COME FROM THE HAIFA GROUP, S. DADO ET AL.

No description provided.

No description provided.

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Two-body strange-particle final states in pi- p interactions at 4.5 and 6 gev/c

Crennell, D.J. ; Gordon, H.A. ; Lai, Kwan-Wu ; et al.
Phys.Rev.D 6 (1972) 1220-1254, 1972.
Inspire Record 73936 DOI 10.17182/hepdata.3601

Results on the following π−p reactions involving a hyperon are studied at 4.5 and 6.0 GeV/c from a high-statistics bubble-chamber experiment. (1) π−p→(Λ, Σ0)K0: Differential cross sections and hyperon polarizations are presented. Comparison with the line-reversed reactions K¯N→(Λ, Σ0)π indicates the failure of the predictions of K*(890) and K*(1420) exchange degeneracy. Effective trajectories for these two reactions are compared. Shrinkage is observed in K¯N→Λπ and not in π−p→ΛK0. (2) π−p→(Λ, Σ0)K*(890)0: Differential cross sections, hyperon polarizations, and K*(890)0 density-matrix elements are determined. ΛK*(890)0 decay correlations are found to impose strong constraints on the scattering amplitudes. The data indicate that both natural- and unnatural-parity exchanges contribute large, but opposite, Λ polarizations. This behavior cannot be explained by a simple exchange model utilizing K and the exchange-degenerate K*(890) and K*(1420) only. Additional trajectories or absorption effects are required to obtain the observed Λ-polarization effects. Comparison of ΛK*(890)0 and Σ0K*(890)0 indicates the greater importance of unnatural-parity exchange in the former reaction. We observe no evidence for deviations from isospin predictions in ΛK*(890)0 production where K*(890)0→K+π− and KS0π0. (3) π−p→ΛK*(1420)0 and ΛK*(1300)0: K*(1420)0 density-matrix elements satisfying positivity constraints are determined allowing for s-wave interference effects. Evidence of the existence of a narrow K*(1300)0→Kππ with a dominant K+ρ− decay mode is observed in the 4.5- and 6-GeV/c data. (4) Σ(1385), Λ(1405), Λ(1520) production: Differential cross sections for the quasi-two-body reactions π−p→Y0K0, where Y0 is Λ(1405), Λ(1520), or Σ(1385)0, are presented and found to have a very similar flat slope in the forward direction. Data for forward K+ scattering in the reaction π−p→Σ(1385)−K+ are presented and discussed. It is argued that this forward peak cannot be explained by kinematic reflection or an s-channel effect and therefore must be due to either two-particle exchange or a single exotic exchange in the t channel.

39 data tables

No description provided.

No description provided.

FIT FOR FORWARD CROSS SECTION AND SLOPE.

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The pi+ p interaction at 1.2 gev/c

Berthon, A. ; Mas, J. ; Narjoux, J.L. ; et al.
Nucl.Phys.B 81 (1974) 431-444, 1974.
Inspire Record 93412 DOI 10.17182/hepdata.7945

Experimental results are presented for the available channels in the 1.2 GeV/ c π + p interaction. An isobaric model with incoherent addition of the amplitudes is used to determine the π, Δ and N ∗ abundance rates in the π + π o p final state. The multipole parameters in the density matrix of the Δ ++ are determined as functions of its production angle.

7 data tables

No description provided.

LEGENDRE POLYNOMIAL FIT USED TO CORRECT FOR ELASTIC EVENTS LOST FROM THE FORWARD BIN.

No description provided.

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