can't find an official documentation however i can say it's omnidirectional as for MSM APs.
here is the 560 specifications if you want a better understand of power/sensitivity based on band and data rates: http://www8.hp.com/h20195/v2/GetPDF.aspx%2F4AA5-1459ENN.pdf
the quick start guide shows how to install it on a wall, a wall-mounted electrical box, or a suspended ceiling, in case: http://h20564.www2.hpe.com/hpsc/doc/public/display?docId=c04895616