The Pulsation-Rotation Interaction: Greatest Hits and the B-Side

It has long been known that rotation can have an appreciable impact on stellar pulsation --- by modifying the usual p and g modes found in the non-rotating case, and by introducing new classes of mode. However, it's only relatively recently that advances in numerical simulations and complementary theoretical treatments have enabled us to model these phenomena in any great detail. In this talk I'll review highlights in this area (the 'Greatest Hits'), before considering the flip side (or the 'B-side', for those of us old enough to remember vinyl records) of the pulsation-rotation interaction: how pulsation can itself influence internal rotation profiles.Comment: 8 pages; to appear in Proc. IAU Symposium 301: Precision Asteroseismolog

GYRE: A New Open-Source Stellar Oscillation Code

We introduce GYRE, a new open-source stellar oscillation code which solves the adiabatic/non-adiabatic pulsation equations using a novel Magnus Multiple Shooting (MMS) numerical scheme. The code has a global error scaling of up to 6th order in the grid spacing, and can therefore achieve high accuracy with few grid points. It is moreover robust and efficiently makes use of multiple processor cores and/or nodes. We present an example calculation using GYRE, and discuss recent work to integrate GYRE into the asteroseismic optimization module of the MESA stellar evolution code.Comment: 2 pages; to appear in Proc. IAU Symposium 301: Precision Asteroseismolog

The coupling between pulsation and mass loss in massive stars

To what extent can pulsational instabilities resolve the mass-loss problem of massive stars? How important is pulsation in structuring and modulating the winds of these stars? What role does pulsation play in redistributing angular momentum in massive stars? Although I cannot offer answers to these questions, I hope at the very least to explain how they come to be asked.Comment: 12 pages, 1 figure, to appear in proceedings of "Unsolved Problems in Stellar Physics" conference (Cambridge, UK, July 2007

Can pulsational instabilities impact a massive star's rotational evolution?

We investigate whether angular momentum transport due to unstable pulsation modes can play a significant role in the rotational evolution of massive stars. We find that these modes can redistribute appreciable angular momentum, and moreover trigger shear-instability mixing in the molecular weight gradient zone adjacent to stellar cores, with significant evolutionary impact.Comment: 6 pages, to appear in Proc. IAU Symposium 250: Massive Stars as Cosmic Engine

06-16-1972 Perliminary Memorandum

Question presented: Whether Texas statutes are unconstitutional as violating due process and equal protection insofar as they permit a legitimate child to require support and maintenance from his natural father, while denying an illegitimate child the right to require his natural father to support and maintain him