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The five globular clusters (GCs) of the Fornax dSph are puzzling for tworeasons; the mass in GCs is high with respect to the galaxy's old stellar mass,and their survival and large distance (> 1 kpc) is at odds with naiveexpectations of dynamical friction. We present here a semi-analytic model,simultaneously addressing both problems in a comprehensive evolutionaryframework for Fornax. Key to the model is inclusion of: 1) hydrodynamicalconstraints on the GC formation locations, 2) self-consistent velocitydistribution functions in the dynamical friction calculations and 3) expansionof GC orbits due to a past dwarf-dwarf merger in the orbit integrations. Thelatter is crucial for reconciling the dynamical survival of the clusters, andtheir chemical properties with respect to the Fornax field stars. We find thatin order for four of the GCs to survive at their observed projected location, adark matter core of radius > 1.5 kpc and a dwarf merger with dynamical massratio of 1:5 to 1:2 with Fornax is required. We support the merger scenario byshowing that aspects of the field star metallicity distribution function andanomalous chemical properties of GC5, are representative of a merging galaxywhich is ~1/3 less massive than Fornax. Together the chemical and dynamicalmodels suggest a scenario where three in-situ GCs in proto-Fornax were ejectedto the outskirts during the merger, a GC4 formed during the merger at about 10Gyrs ago, with GC5 being brought in by the merging galaxy to Fornax.

A dwarf-dwarf merger and dark matter core as a solution to the Globular Cluster problems in the Fornax dSph