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ω photoproduction off hydrogen and deuterium has been studied with the tagged photon beam of the ELSA accelerator in Bonn for photon energies up to 2.0 GeV. The ω meson has been identified via the ω → π$^{0}$ γ → γγγ decay mode, using the combined setup of the Crystal Barrel/TAPS detector systems. Both inclusive and exclusive analyses have been carried out. Differential and total cross-sections have been derived for ω mesons produced off free protons and off protons and neutrons bound in deuterium. The cross-section for the production off the bound neutron is found to be a factor of ≈ 1.3 larger than the one off the bound proton in the incident beam energy region 1.2 GeV < E$_{γ}$ < 1.6 GeV. For higher incident beam energies this factor goes down to ≈ 1.1 at 2.0 GeV. The cross-sections of this work have been used as normalization for transparency ratio measurements.

85 data tables

Table 1

Differential cross-sections of $\omega$ mesons produced off the free proton versus $\cos(\theta^\omega_{\mathrm{c.m.}})$ and versus the momentum transfer to the nucleon, $t$, for incident photon energy $E_\gamma$ = 1.125-1.150 GeV.

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Inclusive differential cross-sections of $\omega$ mesons produced off the free proton versus $\cos(\theta^\omega_{\mathrm{c.m.}})$ and versus the momentum transfer to the nucleon, $t$, for incident photon energy $E_\gamma$ = 1.125-1.150 GeV.

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Table 33

Total cross-section as a function of the incident photon energy for $\omega$ mesons produced off the free proton obtained from exclusive and inclusive analysis$.

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Slope parameter and horizontal level from the fits to the differential cross-sections $d\sigma/dt$ for $\omega$ mesons produced off the free proton.

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Differential cross-sections of $\omega$ mesons produced off the bound proton versus $\cos(\theta^\omega_{\mathrm{c.m.}})$ and versus the momentum transfer to the nucleon, $t$, for incident photon energy $E_\gamma$ = 1.158-1.208 GeV.

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Table 47

Differential cross-sections of $\omega$ mesons produced off the bound neutron versus $\cos(\theta^\omega_{\mathrm{c.m.}})$ and versus the momentum transfer to the nucleon, $t$, for incident photon energy $E_\gamma$ = 1.158-1.208 GeV.

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Table 59

Slope parameter and horizontal level from the fits to the differential cross-sections $d\sigma/dt$ for $\omega$ mesons produced off the bound proton.

Table 60

Slope parameter and horizontal level from the fits to the differential cross-sections $d\sigma/dt$ for $\omega$ mesons produced off the bound neutron.

Table 61

Inclusive differential cross-sections of $\omega$ mesons produced off deuterium versus $\cos(\theta^\omega_{\mathrm{c.m.}})$ and versus the momentum transfer to the nucleon, $t$, for incident photon energy $E_\gamma$ = 1.158-1.208 GeV.

Table 62

Inlusive differential cross-sections of $\omega$ mesons produced off deuterium versus $\cos(\theta^\omega_{\mathrm{c.m.}})$ and versus the momentum transfer to the nucleon, $t$, for incident photon energy $E_\gamma$ = 1.208-1.233 GeV.

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Table 73

Sum of the exclusive differential cross-sections of $\omega$ mesons produced off the bound proton and off the bound neutron versus $\cos(\theta^\omega_{\mathrm{c.m.}})$ and versus the momentum transfer to the nucleon, $t$, for incident photon energy $E_\gamma$ = 1.158-1.208 GeV.

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Total cross-section as a function of the incident photon energy for $\omega$ mesons produced off the bound proton $\sigma_p^{\mathrm{bound}}$, off the bound neutron $\sigma_n^{\mathrm{bound}}$, the sum of the two exclusive cross-sections $\sigma_p^{\mathrm{bound}}+\sigma_n^{\mathrm{bound}}$, the quasi-free inclusive cross-section $\sigma_{\mathrm{incl}}$ and the cross-section off the neutron calculated by $\sigma_{\mathrm{incl}}-\sigma_p^{\mathrm{bound}}$.

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