phil armitage, stony brook


WELCOME to the web site of Phil Armitage at Stony Brook University. I'm interested in using numerical simulations to understand the physics of protoplanetary disks, the formation of extrasolar planets, and the astrophysics of black holes. Topics of recent interest incude the formation of planetesimals, the accretion of planetary envelopes, and the use of machine learning for theoretical studies of planetary dynamics. I currently divide my time between Stony Brook, working with Sabina Sagynbayeva, and the Center for Computational Astrophysics at the Flatiron Institute, where I lead the planet formation group. Collaborations include the EU-funded DUSTBUSTERS network, studying dust and gas in protoplanetary disks, which Stony Brook is part of.

Simulation of circumplanetary disk formation, by Leo Krapp
Recent papers
A thermodynamic criterion for the formation of circumplanetary disks, L. Krapp, K.M. Kratter, A.N. Youdin, P. Benítez-Llambay, F. Masset & Philip J. Armitage, ApJ, submitted

Streaming instability and turbulence: Conditions for planetesimal formation, J. Lim, J.B. Simon, R. Li, P.J. Armitage, D. Carrera, W. Lyra, D.G. Rea, C.-C. Yang & A.N. Youdin, ApJ, submitted

Particle clustering in turbulence: Prediction of spatial and statistical properties with deep learning, Y.-M. Chan, N. Manger, Y. Li, C.-C. Yang, Z. Zhu, P.J. Armitage & S. Ho, ApJ, 960, article id. 19 (2024)

Tidal truncation of circumplanetary disks fails above a critical disk aspect ratio, R.G. Martin, P.J. Armitage, S.H. Lubow & D.J. Price, ApJ, 953, article id. 2 (2023)

The distribution of accretion rates as a diagnostic of protoplanetary disc evolution, R. Alexander, G. Rosotti, P.J. Armitage, G.J. Herczeg, C.F. Manara & B. Tabone, MNRAS, 524, 3948 (2023)

The role of the drag force in the gravitational stability of dusty planet-forming disc - II. Numerical simulations, C. Longarini, P.J. Armitage, G. Lodato, D.J. Price & S. Ceppi, MNRAS, 522, 6217 (2023)

Revisiting collisional dust growth in Class 0/I protostellar disks: Sweep-up can convert a few x 10 Earth masses of dust into kg pebbles in 0.1 Myr, W. Xu & P.J. Armitage, ApJ, 946, article id. 94 (2023)

The role of the drag force in the gravitational stability of dusty planet forming disc - I. Analytical theory, C. Longarini, G. Lodato, G. Bertin & P.J. Armitage, MNRAS, 519, 2017 (2023)

Saturation of the magnetorotational instability and the origin of magnetically elevated accretion discs, M.C. Begelman & P.J. Armitage, MNRAS, 521, 5952 (2023)

Reviews and notes
Demographics of young stars and their protoplanetary disks (C.F. Manara et al., review for Protostars and Planets VII)

Lecture notes on accretion disk physics (arXiv only)

Visualizing the kinematics of planet formation, Disk Dynamics Collaboration

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)

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

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


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.

Philip Armitage