D - boom chuck, D and rock your pinky up and down on the 1st string 3rd fret. I don't know what that chord is called
Check out my tab on
http://bobwolford.com/ I play it in C but that boom chick sound is going between (In your case) D and D6.
I you don't have TablEdit on your computer you can download a free viewer at,
http://www.tabledit.com/download/downlo_e.shtml and download the "TEFview". You will see this "boom-chick in measures 7 and 8.