Abstract: A method and apparatus for increasing the coherence and reducing the emittance of a beam-shaped pulse operates by splitting the pulse into multiple sub-beams, delaying the propagation of the various sub-beams by varying amounts, and then recombining the sub-beams by means of a rotating optical element to form a pulse of longer duration with improved transverse coherence.

Abstract: Micropole undulators for use in the generation of x-rays from moving charged particles are disclosed. Two rows of spaced apart poles are arranged so that each pole produces a magnetic field aligned with all other similar fields. The poles are the ends of "C"-shaped magnets. In each row, adjacent poles are separated by spacers made of a superconducting material.

Abstract: Micropole undulators for use in the generation of x-rays from moving charged particles and methods for manufacturing such undulators are disclosed.One type of micropole undulator has two jaws containing rows of spaced apart poles arranged so that each pole produces a magnetic field aligned with all other similar fields. An external biasing field extends through the jaws so that an overall undulator field of substantially sinusoidal shape and substantially zero average value extends along the undulator axis. Preferably, the poles are bars formed of a magnetizable, but unmagnetized, material so that, after the jaws are assembled, all of the bars can be magnetized simultaneously in a uniform magnetic field of suitable strength.

Abstract: The instant invention comprises a method for freely suspending without any solid material support, a platform in an atmosphere by atmospheric-particle-momentum transfer having opposite surface portions which are structured to have different atmospheric-particle-momentum-transfer characteristics determined by temperature and surface structure. Electromagnetic radiation is transmitted from an antenna with the platform disposed in the atmosphere so that the radiation impinges the platform. A temperature difference between at least one surface portion of the platform and the atmosphere adjacent that surface portion is established by regulating the temperature distribution on the surface of the platform by heating at least one surface portion by the impinging radiation. The net force produced on the platform freely suspends the platform in the atmosphere.

Abstract: A method and system are described for transmitting electromagnetic radiation by using a communications mirror located between about 100 kilometers and about 200 kilometers above ground. The communications mirror is kept aloft above the atmosphere by the pressure of the electromagnetic radiation which it reflects, and which is beamed at the communications mirror by a suitably constructed transmitting antenna on the ground. The communications mirror will reflect communications, such as radio, radar, or television waves up to about 1,100 kilometers away when the communications mirror is located at a height of about 100 kilometers.