Electron density and temperature profiles have been measured in a large-facility beam-plasma-discharge (VB=1.3 KeV, IB=63 ma) at low pressure (P=2--4(10-6)Torr) and low magnetic fields (B=1.2 G). The results follow an exponential behavior and are found to be in good agreement with a simple diffusion model. The favorable comparison between theory and experiment yields the first estimate of cross-field electron diffusion (D⊥e (nom) =2.2 (106) cm2/sec) under conditions intended to simulate Spacelab-borne beam-plasma investigations. This value for D⊥e is orders of magnitude larger than would be expected for a cross-field collisional diffusion process, a result which is identified with the turbulent state of collective beam-plasma interactions.