A new BeppoSAX broad-band ( 0.6–150 keV ) spectrum of the Seyfert 2 galaxy Mkn 3 is presented .
The spectrum provides a direct measurement of a large , neutral column of gas with N _ { H } \sim 10 ^ { 24 } cm ^ { -2 } in the source direction .
The source , as bright as 3C 273 above 10 keV , has a steep ( \Gamma \sim 1.8 ) spectrum without any evidence of a high-energy cutoff up to at least 150 keV .
At lower energies , the data are best modeled with the addition of an unabsorbed reflection component .
Combining these data with previous Ginga and ASCA observations , the Fe K _ { \alpha } and reflection continuum indicate that the reprocessed emission is responding slower than the intrinsic continuum variations suggesting a size of the reprocessor > \lower 4.558 pt \hbox { $ \kern - 10.7 pt { \sim } $ } 2 pc .
Identifying such a reprocessor with a ( close to edge-on ) obscuring torus , the overall result fits well into unified models since , presumably , one can interpret the strong absorption as due to transmission through the rim of the torus and the unabsorbed ( directly viewed ) reflection component as due to reprocessing from the torus inner surface .