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Local kinematics and the local standard of rest
We re-examine the stellar kinematics of the solar neighbourhood in terms of the velocity υ� of the Sun with respect to the local standard of rest. We show that the classical determination of its
Local stellar kinematics from Hipparcos data
From the parallaxes and proper motions of a kinematically unbiased subsample of the Hipparcos Catalogue, it is re-determined as a function of colour the kinematics of main-sequence stars that spiral arms are responsible for the non-axisymmetry and that R0/Rd ≃ 3 to 3, where Rd is the scalelength of the disc.
Mass models of the Milky Way
The proposition that flat rotation curves arise because galaxies have physically distinct haloes rather than outwards-increasing mass-to-light ratios is called into question.
Radial mixing in galactic discs
We show that spiral waves in galaxy discs churn the stars and gas in a manner that largely preserves the overall angular momentum distribution and leads to little increase in random motion. Changes
Chemical evolution with radial mixing
Models of the chemical evolution of our Galaxy are extended to include radial migration of stars and flow of gas through the disc. The models track the production of both iron and α-elements. A model
The Theory of critical phenomena
Here is a much-needed basic text that covers a vital area in physics for beginning graduate students.
Understanding the kinematics of Galactic Centre gas
A coherent picture is constructed on the Galaxy's H I, CO and CS emissions in the region |l| ≤ 10°, |b| ≤ 0.5°. The flow of gas at the Galactic Centre is dominated by a bar that has corotation at r =
Kinematics and history of the solar neighbourhood revisited
We use proper motions and parallaxes from the new reduction of Hipparcos data and Geneva-Copenhagen radial velocities for a complete sample of ∼15 000 main-sequence and subgiant stars, and new Padova