Rear turret is probably an SGreen. The lower beam on the front looks like a BGreen but slashes across the hull.
That's a negatory. One BGreen, four TerSlashers.
Whomever designed the Hecate severely overestimated the effectiveness of the Terslash.......
Well, yeah, but it's still pretty well-gunned; More so than the Typhon and the Hatshepsut (Hatshep using more efficient beams, though.)
I'd wager a Hecate being able to take down a Typhon, but the Hatshepsut has better accuracy, and the Orion simply mounts a better array of weapons.
Well, at least there's one consolation: The TerSlash is way better than the SGreen.
Way better.
It'd be a much better beam if the re-fire time was fifteeen seconds vs. 45. You can at least claim at that point that balance would have a SGreen do low sustained damage. The SGreen as is right now a terribly inefficient weapon. It's good for raiding and getting the first shot in (Smashing another cruiser initialy or at least badly damaging a freighter.), but for not a whole lot else. SVas Mounted on the Hatshepsut is much better. (It works wonderfully if you replace the Subach Turret on the Mentu with a SVas, though that's uncanonical)
Terran beams do have the advantage of being mounted in more numbers than their Vasudan and Shivan counterparts.