A - is captured by a deuteron d (J P = 1 + ) and produces

A π^- is captured by a deuteron d (J^P = 1⁺) and produces the reaction π^-+ d→n + n.

(a) If the capture is from an S wave, what is the total spin of the two neutrons and what is their orbital momentum? 

(b) Show that if the capture is from a P state, the neutrons are in a singlet.