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Contributions to the single-inclusive cross section for quasi-real photoproduction of a hadron $h$ into direct (left) and resolved (right) subprocesses according to Ref.~\cite{Jager:2005uf}. The internal lines represent the photon $\gamma^*$ and partons $\{a, b,c\} = \{q, \bar{q}, g\}$. The central blob describes the hard scattering cross section $\hat{\sigma}$. The peripheral blobs describe the non-perturbative objects: parton distributions of the nucleon, $ f_b^N$, and of the photon, $f_{\protect\rule{0pt}{1.2ex}a}^{\gamma^*}$, and the fragmentation functions of the produced hadron, $D_c^h$.

Contributions to the single-inclusive cross section for quasi-real photoproduction of a hadron $h$ into direct (left) and resolved (right) subprocesses according to Ref.~\cite{Jager:2005uf}. The internal lines represent the photon $\gamma^*$ and partons $\{a, b,c\} = \{q, \bar{q}, g\}$. The central blob describes the hard scattering cross section $\hat{\sigma}$. The peripheral blobs describe the non-perturbative objects: parton distributions of the nucleon, $ f_b^N$, and of the photon, $f_{\protect\rule{0pt}{1.2ex}a}^{\gamma^*}$, and the fragmentation functions of the produced hadron, $D_c^h$.

The asymmetry $A_{LL}$ as a function of $p_{T}$ for charged hadron quasi-real photoproduction on the proton for three rapidity bins. The bands at the bottom indicate the systematic uncertainties, which are dominated by time dependent fluctuations (see \secref{sec:asymmetries_and_systematics}.) Top: positive hadron production; bottom: negative hadron production.

Same as \figref{all_prot}, but for the deuteron.

Fractions of the total cross section at NLO for a deuteron target for the six subprocesses $a+b \rightarrow c+X$ described in \secref{sec:Introduction} versus $p_T$ (left), and corresponding analysing power (right).

Fractions of the total cross section at NLO for a deuteron target for the six subprocesses $a+b \rightarrow c+X$ described in \secref{sec:Introduction} versus $p_T$ (left), and corresponding analysing power (right).

COMPASS asymmetries $A_{LL}$ for a proton target as a function of $p_{T}$ and in three rapidity bins, compared to NLO calculations based on Ref.~\cite{Jager:2005uf} for three different choices for the polarised gluon distribution (see text). Only statistical uncertainties are shown. Error bands on the theory curves represent the uncertainties due to the polarised parton distribution of the photon. Top: positive hadron production; bottom: negative hadron production.

Same as \figref{fig:all_prot_theo}, but for a deuteron target.