  Aims. In this work, we characterize the low mass companion of the A0 field
star HR3549. Methods. We observed HR3549AB in imaging mode with the the NIR
branch (IFS and IRDIS) of SPHERE@VLT, with IFS in YJ mode and IRDIS in the H
band. We also acquired a medium resolution spectrum with the IRDIS long slit
spectroscopy mode. The data were reduced using the dedicated SPHERE GTO
pipeline, purposely designed for this instrument. We employed algorithms such
as PCA and TLOCI to reduce the speckle noise. Results. The companion was
clearly visible both with IRDIS and IFS.We obtained photometry in four
different bands as well as the astrometric position for the companion. Based on
our astrometry, we confirm that it is a bound object and put constraints on its
orbit. Although several uncertainties are still present, we estimate an age of
~100-150 Myr for this system, yielding a most probable mass for the companion
of 40-50MJup and T_eff ~300-2400 K. Comparing with template spectra points to a
spectral type between M9 and L0 for the companion, commensurate with its
position on the color-magnitude diagram.
