Deuteron Photodisintegration at Photon Energies Between 200-{MeV} and 700-{MeV} in Backward Direction

Althoff, K.H. ; Anton, G. ; Bour, D. ; et al.
Z.Phys.C 21 (1983) 149, 1983.
Inspire Record 192906 DOI 10.17182/hepdata.50170

The differential cross section of the deuteron photodisintegration was measured at a protion c.m. angle of 180 degrees and for photon energies between 180 and 730 MeV. The protons were detected in a magnetic spectrometer. The proton energy resolution varied between 30 MeV and 50 MeV FWHM. Since these are the first data at 180 degrees in this energy range a comparison can only be done with data from other laboratories extrapolated to 180 degrees and with theoretical predictions. The agreement with existing calculations is poor. Contributions of dibaryons to the cross section seem not to improve the situation.

1 data table match query

BEAM ERROR D(E) = 50.000 MEV.


Measurement of the Target Asymmetry for the Reaction gamma p --> pi+ n at Photon Energies Between 0.7-GeV and 2.2-GeV and a Pion CM Angle of 65-Degrees

Althoff, K.H. ; Conrad, R. ; Herr, H. ; et al.
Phys.Lett.B 59 (1975) 93-94, 1975.
Inspire Record 104242 DOI 10.17182/hepdata.5536

At the Bonn 2.5.GeV electron synchrotron the target asymmetry for the photoproduction of positive pions has been measured. Data were taken at photon energies between 0.7 and 2.2 GeV and a pion CM-angle of 65°.

2 data tables match query

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

No description provided.


TARGET ASYMMETRY MEASUREMENT OF DEUTERON PHOTODISINTEGRATION AT A PHOTON ENERGY OF 550-MEV

Althoff, K.H. ; Anton, G. ; Bock, B. ; et al.
Z.Phys.C 26 (1984) 175-179, 1984.
Inspire Record 214987 DOI 10.17182/hepdata.16199

The target asymmetry of the deuteron photodisintegration was measured at a photon energy of 550±50 MeV and at proton center-off-mass angles between 25 and 155 degrees.D-butanol andND3 were used as target material yielding a maximum deuteron polarization of 41%. Proton and neutron were detected in coincidence. The data show a structure which cannot be described by the existing analyses.

1 data table match query

Axis error includes +- 8/8 contribution (UNCERTAINTY IN THE DETERMINATION OF THE TARGET POLARIZATION//OTHER SYSTEMATIC ERRORS ARE FROM COMPETING PROCESSES (<2 PCT) AND OTHERS (<1 PCT)).


Measurement of the polarization of the recoil neutron from the photoproduction of charged pions on hydrogen

Althoff, K.H. ; Piel, H. ; Wallraff, W. ; et al.
Phys.Lett.B 26 (1968) 640-641, 1968.
Inspire Record 1099537 DOI 10.17182/hepdata.29335

The polarization of the recoil neutron in the reaction γ + p → π + + n has been measured for a pion c.m.-angle of 90° and a photon energy of 390 MeV. Hydrogen was used as the polarization analyser.

1 data table match query

No description provided.


Measurement of the polarization of the recoil protons from the reaction $\gamma + \rho \rightarrow \rho + \pi^0$ in the region of the second resonance at low pion center of mass angles

Trines, Dieter ; Althoff, K.H. ;
PhD Thesis, Bonn U., Math. Inst., 1972.
Inspire Record 1396209 DOI 10.17182/hepdata.37154

None

1 data table match query

No description provided.


Photoproduction of Negative Pions on a Polarized Neutron Target in the Resonance Region

Althoff, K.H. ; Beckschulze, H. ; Conrad, R. ; et al.
Nucl.Phys.B 96 (1975) 497-508, 1975.
Inspire Record 99642 DOI 10.17182/hepdata.31932

At the Bonn 2.5 GeV electron synchrotron the first measurements of the target asymmetry for the reaction γ + n ↑ → π − + p have been performed. The negative pions were detected in a magnetic spectrometer at a constant pion c.m. angle of 40° and photon energies between 0.45 GeV and 2.0 GeV. Deuterated butanol was used as target material. The polarization of the deuterons was about 16%. The results show a significant difference from the previously measured π + asymmetry.

1 data table match query

No description provided.


Photoproduction of pi+ mesons on polarized protons at photon energies between 0.5 and 2.2 gev

Althoff, K.H. ; Feller, P. ; Herr, H. ; et al.
Nucl.Phys.B 53 (1973) 9-18, 1973.
Inspire Record 84220 DOI 10.17182/hepdata.32593

The target asymmetry T = ( σ ↑ − σ ↓)/( σ ↑ + σ ↓) for the reaction γ p → π + n has been measured at the Bonn 2.5 GeV electron synchrotron for a pion c.m. angle of 40° and γ energies between 0.5 and 2.2 GeV. Butanol was used as the target material. About 35% of the protons could be polarized using the dynamic-polarization method in a continuous-flow cryostat operating at 1°K and 25 kG. The π + mesons were detected in a magnetic-spectrometer system. Considerable structure in the asymmetry was observed.

1 data table match query

Axis error includes +- 11/11 contribution.


Photodisintegration of Polarized Deuterons: Measurement of Angular Distributions at $e (\gamma$) = 450-{MeV}, 550-{MeV} and 650-{MeV}

Althoff, K.H. ; Anton, G. ; Bock, B. ; et al.
Z.Phys.C 43 (1989) 375, 1989.
Inspire Record 277082 DOI 10.17182/hepdata.15455

At the Bonn 2.5 GeV electron synchrotron an angular distribution of the target asymmetry of the reaction γ+d↑→p+n has been measured at photon-lab-energies of 450 and 650 MeV and at proton-CM-angles between 25° and 155°. At 550 MeV the data of our previous run [1] have been improved. Using deuterated ammonia as material for the polarized deuteron target a maximum vector polarization of 44% could be achieved. At 450 and 650 MeV the data are consistent with a smooth sin 2Θ-like distribution. The evidence for a structure around 90° at 550 Mev remains. This might be due to the influence of a higher momentum state (like a dibaryon). The feasibility of measuring the tensor asymmetry of the deuteron photodisintegration with a polarized target has been shown for the first time. Data were taken in a short run for one kinematical setting.

1 data table match query

Errors contain both statistics and systematics.


Positive Pion Photoproduction From Hydrogen at Photon Energies Between 500-{MeV} and 1400-{MeV} in Forward Direction

Althoff, K.H. ; Anton, G. ; Bock, B. ; et al.
Z.Phys.C 18 (1983) 199, 1983.
Inspire Record 189703 DOI 10.17182/hepdata.16352

The differential cross section of the reactionγ+p→π+ was measured at pion CM-angles of 20° and 30° for photon energies between 500 MeV and 1,400 MeV. The pions were detected in a magnetic spectrometer. By measuring each pion trajectory and by offline calculation of the initial pion parameters an energy resolution of about 2.5% FWHM was achieved. The results complete a set of data which were measured in recent years at the Bonn 2.5 GeV synchrotron. In comparison to photoproduction analyses two effects were revealed: The η cusp appears in the energy dependence of the cross section as a sharp drop atKγ=710 MeV. In the region of the third resonance the data show a greater enhancement than predicted by most of the analyses.

1 data table match query

No description provided.


Measurement of the polarization of the recoil proton from the photoproduction of neutral pions on hydrogen in the region of the first resonance. I

Althoff, K.H. ; Kramp, K. ; Matthay, H. ; et al.
Z.Phys. 194 (1966) 135-143, 1966.
Inspire Record 1385256 DOI 10.17182/hepdata.16667

The polarization of the recoil proton from the reaction 7+p--->~pi0+p has been measured using liquid helium as polarization analyser. The photon energy has been varied between 250 and 360 MeV, the pion angle (CM) between 58 and 100.

1 data table match query

No description provided.