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Kinematically complete measurements for Coulomb dissociation of n Li into 9 Li + 2« were made at 28 MeV/nucleon. The n-n correlation function suggests a large source size for the two-neutron emission. The electromagnetic excitation spectrum of n Li has a peak, as anticipated in low-energy dipole resonance models, but a large post-breakup Coulomb acceleration of the 9 Li fragment is observed, indicating a very short lifetime of the excited state and favoring direct breakup as the dissociation mechanism.

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The PHENIX experiment at the BNL Relativistic Heavy Ion Collider (RHIC) has measured electrons with 0:3 < p T < 9 GeV=c at midrapidity (jyj < 0:35) from heavy-flavor (charm and bottom) decays in Au Au collisions at s NN p 200 GeV. The nuclear modification factor R AA relative to p p collisions shows a strong suppression in central Au Au collisions, indicating substantial energy loss of heavy quarks in the medium produced at RHIC energies. A large azimuthal anisotropy v 2 with respect to the reaction plane is observed for 0:5 < p T < 5 GeV=c indicating substantial heavy-flavor elliptic flow. Both R AA and v 2 show a p T dependence different from those of neutral pions. A comparison to transport models which simultaneously describe R AA p T and v 2 p T suggests that the viscosity to entropy density ratio is close to the conjectured quantum lower bound, i.e., near a perfect fluid.