Searching for non gaussian signals in the boomerang 2003 cmb maps

We analyze the BOOMERanG 2003 (B03) 145 GHz temperature map t o constrain the amplitude of a non Gaussian, primordial contribution to CMB fluctuatio ns. We perform a pixel space analysis restricted to a portion of the map chosen in view of high sensi tivity, very low foreground contamina- tion and tight control of systematic effects. We set up an esti mator based on the three Minkowski functionals which relies on high quality simulated data, in cluding non Gaussian CMB maps. We find good agreement with the Gaussian hypothesis and derive the fi rst limits based on BOOMERanG data for the non linear coupling parameter f NL as − 300 < f NL < 650 at 68% CL and − 800 < f NL < 1050 at 95% CL.