In bounds/jump ball question

[John Schaefferkoetter]

Team A takes the ball out of bounds at half court to start the second half. The inbounder throws the ball clear under his own bucket where a team A player and a team B player both catches the ball and come down with it simultaneously. A jump ball is called.

Who should get the ball? Is it alternating possession and team B gets the ball or does team A get the ball again because there is no possession yet?

Thanks in advance