Separated structure functions for the exclusive electroproduction of K+ Lambda and K+ Sigma0 final states.

The CLAS collaboration Ambrozewicz, P. ; Carman, D.S. ; Feuerbach, R.J. ; et al.
Phys.Rev.C 75 (2007) 045203, 2007.
Inspire Record 732363 DOI 10.17182/hepdata.4994

We report measurements of the exclusive electroproduction of $K^+\Lambda$ and $K^+\Sigma^0$ final states from a proton target using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The separated structure functions $\sigma_T$, $\sigma_L$, $\sigma_{TT}$, and $\sigma_{LT}$ were extracted from the $\Phi$- and $\epsilon$-dependent differential cross sections taken with electron beam energies of 2.567, 4.056, and 4.247 GeV. This analysis represents the first $\sigma_L/\sigma_T$ separation with the CLAS detector, and the first measurement of the kaon electroproduction structure functions away from parallel kinematics. The data span a broad range of momentum transfers from $0.5\leq Q^2\leq 2.8$ GeV$^2$ and invariant energy from $1.6\leq W\leq 2.4$ GeV, while spanning nearly the full center-of-mass angular range of the kaon. The separated structure functions reveal clear differences between the production dynamics for the $\Lambda$ and $\Sigma^0$ hyperons. These results provide an unprecedented data sample with which to constrain current and future models for the associated production of strangeness, which will allow for a better understanding of the underlying resonant and non-resonant contributions to hyperon production.

531 data tables

Cross sections for incident energy 2.567 GeV for the Q**2 range 0.5 to 0.8 GeV**2 and W range 1.6 to 1.7 GeV.

Cross sections for incident energy 2.567 GeV for the Q**2 range 0.5 to 0.8 GeV**2 and W range 1.70 to 1.75 GeV.

Cross sections for incident energy 2.567 GeV for the Q**2 range 0.5 to 0.8 GeV**2 and W range 1.75 to 1.80 GeV.

More…

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

No description provided.

No description provided.

No description provided.

More…

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

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

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.

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

More…

ASYMMETRY OF THE REACTION CROSS-SECTION FOR PI+ MESON PHOTOPRODUCTION ON HYDROGEN INDUCED BY POLARIZED PHOTONS IN THE RESONANCE ENERGY REGION. (IN RUSSIAN)

Abramian, L.O. ; Aganyants, Aleksandr O. ; Adamian, F.V. ; et al.
Yad.Fiz. 32 (1980) 128-132, 1980.
Inspire Record 159785 DOI 10.17182/hepdata.18977

None

2 data tables

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

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


Measurement of the polarization of the recoil proton in $\gamma+p \to p + \pi^{0}$ using a propane-ethane bubble chamber

Bertanza, L. ; Mannelli, I. ; Santucci, S. ; et al.
Nuovo Cim. 24 (1962) 734-745, 1962.
Inspire Record 1187694 DOI 10.17182/hepdata.37757

The polarization of the recoil proton in γ + p → p + π0 has been measured at photon energies of 725 MeV and 900 MeV for centerof-mass angles near 90° using a small propane-ethane gas bubble chamber. Protons emerging from a liquid hydrogen target are momentum-analysed with a magnet, and the scattering from carbon observed in the bubble chamber. A counter telescope rejects pions and electrons, and protons from multiple pion processes are discriminated against by keeping the peak bremsstrahlung energy just above the mean photon energy. The visual method of observing scattering asymmetries has the advantage of being insensitive to systematic asymmetries in the incoming proton flux. It also quickly eliminates strongly inelastic scatters (stars), and provides a complete angular distribution from which the fraction of scatters which are inelastic can be deduced. The effect of inelastic scatters upon the scattering asymmetry is large when the energy-loss resolution is poor, an inherent problem with bremsstrahlung beams. The counting rate for this small chamber (3.4g/cm2 carbon scatterer) was 11 scatters/hour using every 5th synchrotron pulse; larger chambers with more dense scatterers (such as Freon) could give higher counting rates. Results are fork = 725MeV and ϑ (pion) = 87° (cm.), P=0.74±0.20, and for k=900MeV and ϑ (pion) = 70°, P=.51±.7. P is taken to be positive along the directionK xp, wherep is the momentum of the outgoing proton.

1 data table

No description provided.