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Star distribution around a massive black hole in a globular cluster
To predict the likely distribution of stars around a massive black hole in the core of a cluster of stars, an equation of the Fokker-Planck type is derived that describes the diffusion of stars in
Models for the Galaxy and the Predicted Star Counts
A detailed model is constructed for the disk and spheroid components of the Galaxy from which the distribution of visible stars and mass in the Galaxy is calculated. The application of star counts to
Solar Models: Current Epoch and Time Dependences, Neutrinos, and Helioseismological Properties
We calculate accurate solar models and report the detailed time dependences of important solar quantities. We use helioseismology to constrain the luminosity evolution of the Sun and report the
Hubble Space Telescope Images of a Sample of Twenty Nearby Luminous Quasars
Observations with the Wide-Field Camera of the Hubble Space Telescope are presented for a representative sample of 20 intrinsically luminous quasars with redshifts smaller than 0.30. These
Observations suggest that {gamma}-ray bursts (GRBs) are produced by the dissipation of the kinetic energy of a relativistic fireball. We show that a large fraction, {ge}10{percent}, of the fireball
Star distribution around a massive black hole in a globular cluster. II. Unequal star masses
The steady-state distribution of stars around a massive black hole in a globular cluster is determined by solving numerically the coupled time-dependent Boltzmann equations for a system containing
On the simultaneous analysis of several complete samples - The V/Vmax and Ve/Va variables, with applications to quasars
We derive methods for applying the V/V/sub max/ variable when several complete samples are analyzed simultaneously. A new, related, variable, V/sub e//V/sub a/, which is superior to V/V/sub max/ when
Solar models with helium and heavy-element diffusion
Helium and heavy-element diffusion are both included in precise calculations of solar models. In addition, improvements in the input data for solar interior models are described for nuclear reaction
Element Diffusion in the Solar Interior
We study the diffusion of helium and other heavy elements in the solar interior by solving exactly the set of flow equations developed by Burgers for a multi-component fluid, including the residual
Helioseismological Implications of Recent Solar Abundance Determinations
We show that standard solar models are in good agreement with the helioseismologically determined sound speed and density as a function of solar radius, the depth of the convective zone, and the