AA question for the math guys

[grjr]

No reads on anyone.

When the K hit the turn here and the Button went off I figured he either had AK or KK. I assumed it was close to 50/50 either way so I kept betting.

Could anyone tell me the exact odds between the two once we see the K on the turn?

Also, would you cap the river on a blank if UTG+1 dropped out early?

Party Poker 0.5/1 Hold'em (9 handed) converter

Preflop: Hero is UTG with A[img]/images/graemlins/spade.gif[/img], A[img]/images/graemlins/diamond.gif[/img].
<font color="#CC3333">Hero raises</font>, <font color="#CC3333">UTG+1 3-bets</font>, <font color="#666666">4 folds</font>, <font color="#CC3333">Button caps</font>, <font color="#666666">2 folds</font>, Hero calls, UTG+1 calls.

Flop: (13.50 SB) 3[img]/images/graemlins/spade.gif[/img], 2[img]/images/graemlins/club.gif[/img], 7[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, <font color="#CC3333">UTG+1 bets</font>, <font color="#CC3333">Button raises</font>, Hero calls, UTG+1 calls.

Turn: (9.75 BB) K[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, UTG+1 checks, <font color="#CC3333">Button bets</font>, <font color="#CC3333">Hero raises</font>, UTG+1 calls, <font color="#CC3333">Button 3-bets</font>, <font color="#CC3333">Hero caps</font>, UTG+1 calls, Button calls.