For line-of-sight purposes would the Sanctuary radius be like the BC/GM standing in the center of a 6" circular template?

For the daemons being unable to draw line of sight through it, yes. However, it is important to note that this area is not blocked by terrain in any way -- the psyker can stand on one side of a wall and prevent daemons from shooting lengthwise down its other side.

I shall quote the rules as written in DH codex.
This is gw copywright and i wright it in educatory purposes, if gw complains i will remove the quote.

"Sanctuary is a psychic power that may be used at the beginning of the psyker's turn. Deamons may not move within 3" of the psyker for any reason- they treat this area as impassable and cannot draw line of sight through it. Deamons already within this radius are pushed directly away from him until they are 3" distant, and must retain unit coherency if possible. This can effectively end a combat. Any Deamon that enters play within 3" of the psyker whilst he is using sanctuary is automatically destroyed. The effects of this power last until the psyker moves, shoots or uses another psychic power, although he can fight as normal in close combat."

Damn, that one is nice.

I would measure it 3" from his base so if he is on a 60mm base it would be...... wait a moment..... 4.5" from the centre of the base in a circle.

A 9" big solid block, impassible for the deamonkind. I'm coming up with some nasty tactics for this baby when i'm gooing too face a friends future Slaneesh army.

I'm asking this now because I think most players will be adding Sanctuary if we see a lot of Daemon armies in the near future. And if what I'm reading on the B&C forum turns out to be the norm those Daemons are gonna be sick.

yess I will be a great help, however your GM won't be able to shoot, so don't tool him up too much since he will be a standing wall in front of your army and he will be using his power nearly every turn.

So lets think this through.

My BC and 3 termy squad is in combat with a squad of Daemons. At the start of the turn I cast Sanctuary pushing them away- ending combat. I'm then free to move shoot and assault at will?

I just need to find how many points for this? WoooHooo!!!

15, and i would put it on a brother captain or inquisitor standing with the heavy guys.

Deamons i cc, inquisitor casts sanctuary, cc ends, grand master with grey knight termies fire and then charge.

Repeat!

Hehehe. enemy=owned!

How about this one Inquisitor with sanctuary and a pair of mystics with a minimum sized purgatorian squad packed with psycannons.
Turn 1:Cast sanctuary, pack both squads inside the radius. Enemy begins deep striking letting you fire at each squad within 4D6". They cant hit back unless the soul grinder has an orderance weapon weapon.

They can't hit back full stop as they have NO guess range weapons.

My HQ BC is geting this and maybe an incinerator.

This thing is fat nice against deamons, no argue, totally missed its usefullness.

Could be that i have never met a deamon and so have never used anything else than stuff that does direct damage to enemies, in str!