Gluon depletion and J/psi suppression in pA collisions
The gluon distribution of a nucleon propagating through a nucleus can change depending on how far the penetration depth is. It is a nonperturbative process that we describe by an evolution equation. The kernel of the integral equation is to be determined by a phenomenological study of J/psi suppression in pA collision. The data of E866 on alpha(x_F) shows significant dependence on x_F at large x_F. It presents a feature that has not been explained by any hadronic absorption model. We show that gluon depletion is a simple mechanism that can account for it. The result has far-reaching implications on the role of partons in nuclear collisions.
Abstract A model reduction for a compressible flow with combustion is performed using the POD-Galerkin procedure. The model parameters are determined by an optimization. The obtained reduced-order model is incorporated in a model predictive controller and results are shown from a closed-loop CFD-simulation. The controller influences the fuel mass-flow boundary condition to control the temperature at a certain point within the computational domain.