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AX J1745.6-2901 is a high-inclination (eclipsing) transient neutron star (NS)Low Mass X-ray Binary (LMXB) showcasing intense ionised Fe K absorption. Wepresent here the analysis of 11 XMM-Newton and 15 NuSTAR new data-sets(obtained between 2013-2016), therefore tripling the number of observations ofAX J1745.6-2901 in outburst. Thanks to simultaneous XMM-Newton and NuSTARspectra, we greatly improve on the fitting of the X-ray continuum. During thesoft state the emission can be described by a disk black body ($kT\sim1.1-1.2$keV and inner disc radius $r_{DBB}\sim14$ km), plus hot ($kT\sim2.2-3.0$ keV)black body radiation with a small emitting radius ($r_{BB}\sim0.5-0.8$ km)likely associated with the boundary layer or NS surface, plus a faintComptonisation component. Imprinted on the spectra are clear absorptionfeatures created by both neutral and ionised matter. Additionally, positiveresiduals suggestive of an emission Fe K$\alpha$ disc line and consistent withrelativistic ionised reflection are present during the soft state, while suchresiduals are not significant during the hard state. The hard state spectra arecharacterised by a hard ($\Gamma\sim1.9-2.1$) power law, showing no evidencefor a high energy cut off ($kT_e>60-140$ keV) and implying a small opticaldepth ($\tau<1.6$). The new observations confirm the previously witnessed trendof exhibiting strong Fe K absorption in the soft state, that significantlyweakens during the hard state. Optical (GROND) and radio (GMRT) observationssuggest for AX J1745.6-2901 a standard broad band SED as typically observed inaccreting neutron stars.

NuSTAR + XMM-Newton monitoring of the neutron star transient AX J1745.6-2901