  The young open cluster NGC 6611 includes among its candidate members a class
of peculiar objects with interesting properties: blue stars with infrared IR
excesses. These stars show excesses in IR bands, signature of the presence of a
circumstellar disk, but optical colors typical of older field stars. In order
to confirm their membership to the cluster, it is therefore important to use
new spectroscopic observations, together with previous photometric data. We aim
at confirming the membership of these objects and at investigating their
physical properties to verify whether the observed colors are intrinsic or
altered by the presence of the disk or by the accretion processes. We analyze
the intermediate resolution spectroscopic data obtained for a subsample of blue
stars in NGC 6611 with FLAMES. In particular, we focus on the study of: 1) the
profile of the Ha emission line, to select stars with accretion and outflow
activity; 2) the Li absorption line, used as a youth indicator; 3) the radial
velocity. Using the spectroscopic analysis, it has been possible to investigate
the presence of the Li absorption line as well as to discriminate between stars
with inert or active disk. In particular, from the analysis of the Ha emission
line we were able to infer the activity due to the accretion and outflow
processes and the variability of the emission. We also investigated the
binarity of the blue stars and their membership to NGC 6611.
