134 citations · 259 across the 3 of their papers we have counts for
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HST Observations of the White Dwarf Cooling Sequence of M4
Brad Hansen, Harvey Richer, Greg Fahlman +7
We investigate in detail the white dwarf cooling sequence of the globular cluster Messier 4. In particular we study the influence of various systematic uncertainties, both observat…
Early planet formation as a trigger for further planet formation
Philip J. Armitage, Brad M. S. Hansen
Recent discoveries of extrasolar planets at small orbital radii, or with significant eccentricities, indicate that interactions between massive planets and the disks of gas and dus…
Isochrones and Luminosity Functions for Old White Dwarfs
Harvey B. Richer, Brad Hansen, Marco Limongi +3
Using a new grid of models of cooling white dwarfs, we calculate isochrones and luminosity functions in the Johnson-Kron/Cousins and HST filter sets for systems containing old whit…