Research Papers in Physics and Astronomy


Date of this Version



Physics 5, 88 (2012).

DOI: 10.1103/Physics.5.88



Copyright (c) 2012 American Physical Society. Used by permission.


Experimental measurements with an x-ray laser test models of how ions behave in plasmas, like those found in stars and laser fusion research.

It takes a strong electric field to ionize atoms or ions in the creation of plasmas. These fields can be generated in lightning bolts (electric discharges), neon light bulbs, at the focus of a laser, and in the path of particle beams. It is perhaps less obvious that plasma itself can also have sufficiently strong fields within it to further ionize ions, since one might expect equal amounts of positive and negative charge would cancel each other out. In Physical Review Letters, Orlando Ciricosta at the University of Oxford, UK, and colleagues make use of the world’s brightest x-ray laser source, the Linac Coherent Light Source (LCLS) at the Stanford Linear Accelerator [1], to create a plasma dense enough to test models of how ionization occurs in matter approaching that found in astrophysical bodies or created in thermonuclear fusion [2].