Multiple parton interactions and forward double pion production in pp and dA scattering

Understand

We estimate the contributions by double-parton interactions to the cross sections for pp->pi^0 pi^0 X and dA->pi^0 pi^0 X at RHIC.

• We find that such contributions become important at large forward rapidities of the produced pions.
• This is in particular the case for dA scattering, where they strongly enhance the azimuthal-angular independent "pedestal" component of the cross section, providing a natural explanation of this feature of the RHIC dA data.
• We argue that the discussed processes open a window to studies of double quark distributions in nucleons.