IN a paper on secondary radiation from gases subject to X-rays (Phil. Mag ... More recently I have found that from light solids which emit a secondary radiation differing little from the primary ...

Generating X-rays that have the properties of laser light has been a long-standing goal for experimental science. Here we describe the emission of highly collimated, spatially coherent X-rays ...

The direction of the ray may also change. This property of waves is called refraction and commonly occurs with light rays. A normal is a dotted line drawn perpendicular to the surface of the ...