Susan A. Lamb

Associate Professor of Physics and of astronomy

Professor Susan Lamb received her bachelor's degree in physics and applied mathematics from Queen Mary College, London University, in 1969 and her D. Phil. in astrophysics from Oxford University in 1973. She is presently an associate professor of physics and of astronomy at the University of Illinois.

A theoretical astrophysicist, Professor Lamb studies the conditions under which stars may form from the collision of galaxies in distant space. In her most recent work, she used images of galaxy collisions obtained from the Hubble Space Telescope and several ground-based telescopes, together with supercomputer simulations conducted at the National Center for Supercomputing Applications on campus, to show for the first time a link between the progression of star formation across a colliding galaxy and the regions of dense gas formed after the collision.

Research Area : Theoretical astrophysics; galaxy collisions and star formation

Description of Current Research

Global Star Formation in Impact-induced Starburst Galaxies
The first impact of two colliding galaxies takes place on a time scale of approximately 108 years, the dynamical time scale. Within this period it is anticipated that much star formation will be triggered as a result of density increases and shocks in the gas which are produced by inflow to the nuclear regions. We are currently comparing our array of simulations of galaxy collisions to observations of collisionally produced starburst galaxies (both our own observations and those of others) and investigating the resulting implications for both the stellar and gaseous components.

Active Galactic Nuclei, Dense Stellar Systems, and Galactic Environment
We are investigating a self-consistent model on a large range of scales to understand the processes leading to nuclear activity in galaxies. Current observations support the view that interactions between galaxies may be crucial in triggering episodes of activity in some active galactic nuclei. Interactions also trigger some starbursts, and we are investigating the relationship between these two phenomena. We employ numerical simulations of colliding galaxies and analytical studies of the physics of the central regions of galaxies to obtain a detailed model that can be compared to observations of these systems.

Lamb Research Group

Selected Publications

L. M. Young, E. Rosolowsky, J. H. van Gorkom, and S. A. Lamb, "The Evolution of the Interstellar Medium in the Mildly Disturbed Spiral Galaxy NGC 4647," Ap. J. 650, 166-179 (2006).

S.A. Lamb and N.C. Hearn "Collisions and mergers of disk galaxies: Hydrodynamics of star forming gas," Astrophys. & Space Sci. 284, 479-482 (2003).

J.C. McDowell et al., " Chandra observations of extended X-ray emission in Arp 220," Ap. J. 591, 154-166 (2003).

D.L. Clements et al., "Chandra observations of ARP 220: The nuclear source," Ap. J. 581, 974-980 (2002).

N.C. Hearn and S.A. Lamb, " ARP 119: A high-speed galaxy collision with episodic star formation," Ap. J. 551, 651-670 (2001).