Phil Armitage, Theoretical Astrophysics at the University of Colorado

WELCOME! to the web site of Phil Armitage at JILA, where I am an Adjoint Fellow with interests in theoretical and computational astrophysics. Current areas of interest include the dynamics of strongly magnetized disks around black holes, the formation of planetesimals, the accretion of planetary envelopes, and the use of machine learning to study planetary system evolution. I am based at Stony Brook University and at the Flatiron Institute's Center for Computational Astrophysics. At JILA I collaborate closely with Mitch Begelman and his group.

Simulation of accretion disk turbulence, by Jake Simon

Recent papers
Local simulations of heating torques on a luminous body in an accretion disk, A. Hankla, Y.-F. Jiang, & P.J. Armitage, ApJ, submitted

Turbulence regulates the rate of planetesimal formation via gravitational collapse, D.A. Gole, J.B. Simon, R. Li, A.N. Youdin, & P.J. Armitage, ApJ, submitted

Simulation of a compact object with outflows moving through a gaseous background, X. Li, P. Chang, Y. Levin, C.D. Matzner, & P.J. Armitage, MNRAS, 494, 2327 (2020)

Strongly magnetized accretion disks: structure and accretion from global magnetohydrodynamic simulations, B. Mishra, M.C. Begelman, P.J. Armitage, & J.B. Simon, MNRAS, 492, 1855 (2020)

The mass and size distribution of planetesimals formed by the streaming Instability. II. The effect of the radial gas pressure gradient, C.P. Abod, J.B. Simon, R. Li, P.J Armitage, A.N. Youdin, & K.A. Kretke, ApJ, 883, article id. 192 (2019)

Reviews and notes
The influence of black hole binarity on Tidal Disruption Events (Coughlin et al., chapter for Springer Space Science Reviews volume)

Physical processes in protoplanetary disks (Armitage, 45th Saas-Fee Advanced Course "From Protoplanetary Disks to Planet Formation")

A brief overview of planet formation (Armitage, short introduction for the Handbook of Exoplanets)

The dispersal of protoplanetary disks (Alexander et al., Protostars and Planets VI, 2014)

The long-term dynamical evolution of planetary systems (Davies et al., Protostars and Planets VI, 2014)

Dynamics of protoplanetary disks (Armitage, ARA&A, 2011)

Lecture notes on the formation and early evolution of planetary systems (arXiv only)

Textbook

Personal I did my undergraduate and graduate work at the University of Cambridge, working with Cathie Clarke at the Institute of Astronomy as my primary advisor. I was a postdoc at CITA and MPA, a lecturer at St Andrews, and a professor at the University of Colorado (2002-2018) before moving to New York.

Beyond work I enjoy hiking, often combined with photography. My main focus is landscapes, but over the years I've also made trips to photograph bears in some spectacular spots in Alaska.