AA no hearts against three hearts on turn, opponent bets 1/2 pot

[CmnDwnWrkn]

Full Tilt No-Limit Hold'em, $0.50 BB (5 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

Hero ($49.50)
UTG ($50)
MP ($32.55)
Button ($25.60)
SB ($26.50)

Preflop: Hero is BB with A[img]/images/graemlins/club.gif[/img], A[img]/images/graemlins/diamond.gif[/img].
<font color="#CC3333">MP raises to $1</font>, <font color="#666666">2 folds</font>, <font color="#CC3333">Hero raises to $4.5</font>, MP calls $3.

Flop: ($8.75) 5[img]/images/graemlins/diamond.gif[/img], 6[img]/images/graemlins/heart.gif[/img], J[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
<font color="#CC3333">Hero bets $6</font>, MP calls $6.

Turn: ($20.75) 4[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
Hero checks, <font color="#CC3333">MP bets $10</font>, Hero???


Thoughts on how to best play Turn please...