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In order to understand the gluon contribution to the nucleon spin, someexperiments can study the production of hadrons at high transverse momemtumfrom lepton-nucleon or nucleon-nucleon scattering. RHIC has recently measuredsuch double spin asymmetries $A_{LL}(p_T)$ for pion production at high centerof mass energies, and inclusion of its data to global fits based on NLOcollinear pQCD calculations gives some constraints on the gluon polarization inthe range $0.05<x_g<0.2$.  To complement these results at COMPASS range, we will present preliminaryCOMPASS results on double longitudinal spin asymmetries $A_{LL}(p_T)$ forsingle hadron production measured on deuteron and proton target at $Q^2<1$GeV$^2$, $p_T>1$ GeV/c and center of mass energy $\sqrt{s}\approx 18$ GeV. AllCOMPASS data taken from 2002 to 2011 by scattering 160 GeV polarized muons onlongitudinally polarized $^6$LiD and NH$_3$ targets have been used, and thenumber of hadrons collected with $p_T>1$ GeV/c for this analysis amounts toabout 10 millions. The obtained asymmetries will be compared to theoreticalpredictions of at NLO without gluon resummation calculation.

$A_{LL}(p_T)$ for single hadron photoproduction at high $p_T$