ABSTRACT An investigation of the kinematics of the M31 globular cluster system (GCS) yields clues... more ABSTRACT An investigation of the kinematics of the M31 globular cluster system (GCS) yields clues as to the mechanisms which may have been involved in its formation. There are signs of a kinematically distinct, metal-rich subsystem which is concentrated towards the center of the galaxy. In addition, a search for substructure in position and velocity parameter space reveals the presence of several groups of globular clusters in the M31 GCS. Numerical simulations indicate that it is possible that such groups may represent the remnants of recent satellite galaxy mergers with M31.
ABSTRACT Terrestrial WIMP and axion detection experiments probe the local velocity-space distribu... more ABSTRACT Terrestrial WIMP and axion detection experiments probe the local velocity-space distribution of dark matter particles. We review the theoretical approaches that have been used to model this distribution. We then describe a new method, to be combined with standard cosmological N-body simulations, that allows one to extract a local velocity-space distribution function in exquisite detail. Preliminary results and implications for direct detection experiments are discussed.
ABSTRACT An investigation of the kinematics of the M31 globular cluster system (GCS) yields clues... more ABSTRACT An investigation of the kinematics of the M31 globular cluster system (GCS) yields clues as to the mechanisms which may have been involved in its formation. There are signs of a kinematically distinct, metal-rich subsystem which is concentrated towards the center of the galaxy. In addition, a search for substructure in position and velocity parameter space reveals the presence of several groups of globular clusters in the M31 GCS. Numerical simulations indicate that it is possible that such groups may represent the remnants of recent satellite galaxy mergers with M31.
The Milky Way may have formed through the aggregation of many small, dark matter dominated object... more The Milky Way may have formed through the aggregation of many small, dark matter dominated objects. If this process is still on going, there is the possibility that a subhalo will be passing through our location in the Galaxy today. Such an event may have important implications for dark matter search experiments and in particular, leave a unique signature in the energy spectrum of dark matter particles detected in terrestrial search experiments. We calculate the probability distribution function (PDF) for the local dark matter density including the effects of recently merged subhalos. An analytic model is used to estimate the accretion rate of subhalos while N-body simulations incorporate the effects of tidal disruption.
ABSTRACT An investigation of the kinematics of the M31 globular cluster system (GCS) yields clues... more ABSTRACT An investigation of the kinematics of the M31 globular cluster system (GCS) yields clues as to the mechanisms which may have been involved in its formation. There are signs of a kinematically distinct, metal-rich subsystem which is concentrated towards the center of the galaxy. In addition, a search for substructure in position and velocity parameter space reveals the presence of several groups of globular clusters in the M31 GCS. Numerical simulations indicate that it is possible that such groups may represent the remnants of recent satellite galaxy mergers with M31.
ABSTRACT Terrestrial WIMP and axion detection experiments probe the local velocity-space distribu... more ABSTRACT Terrestrial WIMP and axion detection experiments probe the local velocity-space distribution of dark matter particles. We review the theoretical approaches that have been used to model this distribution. We then describe a new method, to be combined with standard cosmological N-body simulations, that allows one to extract a local velocity-space distribution function in exquisite detail. Preliminary results and implications for direct detection experiments are discussed.
ABSTRACT An investigation of the kinematics of the M31 globular cluster system (GCS) yields clues... more ABSTRACT An investigation of the kinematics of the M31 globular cluster system (GCS) yields clues as to the mechanisms which may have been involved in its formation. There are signs of a kinematically distinct, metal-rich subsystem which is concentrated towards the center of the galaxy. In addition, a search for substructure in position and velocity parameter space reveals the presence of several groups of globular clusters in the M31 GCS. Numerical simulations indicate that it is possible that such groups may represent the remnants of recent satellite galaxy mergers with M31.
The Milky Way may have formed through the aggregation of many small, dark matter dominated object... more The Milky Way may have formed through the aggregation of many small, dark matter dominated objects. If this process is still on going, there is the possibility that a subhalo will be passing through our location in the Galaxy today. Such an event may have important implications for dark matter search experiments and in particular, leave a unique signature in the energy spectrum of dark matter particles detected in terrestrial search experiments. We calculate the probability distribution function (PDF) for the local dark matter density including the effects of recently merged subhalos. An analytic model is used to estimate the accretion rate of subhalos while N-body simulations incorporate the effects of tidal disruption.
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Papers by David Stiff