The SPARC_LAB Thomson source is presently under
commissioning at LNF. An electron beam of energy
between 30-150 MeV collides head-on with the laser
pulse provided by the Ti:Sapphire laser FLAME,
characterized in this phase by a length of 6 ps FWHM and
by an energy ranging between 1 and 5 J. The key features
of this system are the wide range of tunability of the Xrays
yield energy, i.e. 20-500 keV, and the availability of a
coupled quadrupole and solenoid focusing system,
allowing to reach an electron beam size of 10-20 microns
at the interaction point. The experimental results obtained
in the February 2014 shifts are presented
