HEPData Search

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Forward peak in $\pi^+$ photoproduction

Buschhorn, G. ; Heide, P. ; Kötz, U. ; et al.

Phys.Lett.B 25 (1967) 622-623, 1967.

Inspire Record 1392927 DOI 10.17182/hepdata.29549

The π+—photoproduction cross section is found to have a peak in the forward direction in disagreement with simple Regge pole models.

1 data table

Table 1

No description provided.

Cross section measurement of charged pion photoproduction from hydrogen and deuterium.

The Jefferson Lab Hall A collaboration Zhu, L.Y. ; Arrington, J. ; Averett, T. ; et al.

Phys.Rev.Lett. 91 (2003) 022003, 2003.

Inspire Record 601768 DOI 10.17182/hepdata.31722

We have measured the differential cross section for the gamma n --> pi- p and gamma p --> pi+ n reactions at center of mass angle of 90 degree in the photon energy range from 1.1 to 5.5 GeV at Jefferson Lab (JLab). The data at photon energies greater than 3.3 GeV exhibit a global scaling behavior for both pi- and pi+ photoproduction, consistent with the constituent counting rule and the existing pi+ photoproduction data. Possible oscillations around the scaling value are suggested by these new data The data show enhancement in the scaled cross section at a center-of-mass energy near 2.2 GeV. The cross section ratio of exclusive pi- to pi+ photoproduction at high energy is consistent with the prediction based on one-hard-gluon-exchange diagrams.

1 data table

Table 1

Differential cross section at THETA(CM) = 90 degrees.

Threshold structure of the quasifree p + n --> d + eta reaction.

Calen, H. ; Dyring, J. ; Fransson, K. ; et al.

Phys.Rev.Lett. 80 (1998) 2069-2072, 1998.

Inspire Record 468434 DOI 10.17182/hepdata.19524

The quasifree p+n→d+η reaction cross section has been measured at the threshold using 1295 MeV protons in the CELSIUS storage ring and an internal cluster-jet deuterium target. The kinematics is chosen such that the target proton can be assumed to be a spectator. The Fermi momentum of the target neutron is used to extract the energy dependence of the cross section by reconstructing the kinematics on an event-by-event basis. The data cover excess energies from threshold to 10 MeV in the center of mass of the final dη system. Approaching the threshold the cross section is enhanced compared to what is expected from phase space. This behavior is typical for a strong final-state interaction.

1 data table

Table 1

Cross section as a function of the C.M. excess energy.

CROSS-SECTION ASYMMETRY OF THE gamma n ---> pi- p REACTION BY POLARIZED PHOTONS IN THE THIRD AND FOURTH RESONANCE REGIONS

Adamian, F.V. ; Akopian, G.G. ; Galumian, P.I. ; et al.

EFI-722-37-84-YEREVAN, 1984.

Inspire Record 206944 DOI 10.17182/hepdata.18433

None

5 data tables

Table 1

No description provided.

Table 2

No description provided.

Table 3

No description provided.

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MEASUREMENTS OF SHADOWING IN LOW Q**2 ELECTROPRODUCTION ON NUCLEI

Bailey, J. ; Botterill, D.R. ; Montgomery, Hugh E. ; et al.

Nucl.Phys.B 151 (1979) 367-388, 1979.

Inspire Record 132234 DOI 10.17182/hepdata.34763

Measurements of inelastic electron scattering have been made in the range 2.2 < ν < 3.8 GeV and 0.1 < | Q 2 | < 0.3 (GeV/ c ) 2 , on a selection of nuclei ranging from hydrogen and deuterium to uranium, by measuring the scattered electron only. Detailed calculations have been made of the contribution of radiative tails to the measured yield. The results show a small ‘shadowing’ consistent with other electroproduction experiments, and also with photoproduction experiments in this ν range, but the shadowing decreases rapidly as | Q 2 | increases.

4 data tables

Table 1

DEUTERIUM TO HYDROGEN CROSS SECTION RATIO (PER NUCLEON). FOR E(P=3) = 2.25 AND THETA = 8.5, THE RATIO IS 0.911 +- 0.037 (DSYS = 0.040).

Table 2

No description provided.

Table 3

No description provided.

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Experimental Study of Nuclear Shadowing in Photoproduction

Michalowski, S. ; Andrews, D. ; Eickmeyer, J. ; et al.

Phys.Rev.Lett. 39 (1977) 737-740, 1977.

Inspire Record 124559 DOI 10.17182/hepdata.20970

The total cross section for hadron production by high-energy photons has been measured from a number of nuclei ranging from hydrogen to uranium. Some shadowing is observed at a level considerably less than predicted by conventional vector-meson dominance but consistent with a modified theory. The energy dependence predicted by vectormeson dominance is observed. The shadowing in heavy nuclei shows a smooth transition from electroproduction to photoproduction.

1 data table

Table 1

No description provided.

Measurement of the Total Cross-Section Difference for p p Scattering in Longitudinal Spin States

Auer, I.P. ; Colton, E. ; Hill, D. ; et al.

Phys.Lett.B 67 (1977) 113-116, 1977.

Inspire Record 4411 DOI 10.17182/hepdata.27581

We have measured the total cross-section difference for pp scattering in initial spin states parallel to the beam direction at beam momenta of 1.17, 1.47, 1.69, 1.97 and 2.49 GeV/ c . This measurement was done in a standard transmission experiment. A striking energy dependence is observed with a maximum difference of −16.9 mb at P lab = 1.47 GeV/ c .

2 data tables

Table 1

PRELIMINARY RESULTS.

Table 2

PRELIMINARY RESULTS.

Resonance Production in pi- n Interactions at 5-GeV (Four Particle Final States)

Amaglobeli, N.S. ; Budagov, Yu.A. ; Vinogradov, V.B. ; et al.

Yad.Fiz. 23 (1976) 378-382, 1976.

Inspire Record 112763 DOI 10.17182/hepdata.19076

None

1 data table

Table 1

CORRESPONDING PI+ P CROSS SECTIONS QUOTED. SECONDARY INTERACTIONS OF RHO0 AND DEL- WITH INTRANUCLEAR NUCLEONS SUPPRESSES SIG COMPARED WITH PI+ P DATA.

$\pi^+$ production with linearly polarized photons

Geweniger, C. ; Heide, P. ; Kötz, U. ; et al.

Phys.Lett.B 29 (1969) 41-44, 1969.

Inspire Record 56795 DOI 10.17182/hepdata.29060

Single π + production on protons by linearly polarized photons of 2.5 to 5 GeV was measured at squared four momentum transfers t between −0.01 and −0.6 (GeV/ c ) 2 . The results show that the differential cross section d σ ⊥ d t with the electric vector of the photon perpendicular to the reaction plane is much larger than d σ ‖ d t with the electric vector parallel to the reaction plane. The predictions of Regge models and of the vector meson dominance model are briefly discussed.

3 data tables

Table 1

Axis error includes +- 0.0/0.0 contribution (?////).

Table 2

Axis error includes +- 0.0/0.0 contribution (?////).

Table 3

Axis error includes +- 0.0/0.0 contribution (?////).