Systems for Simultaneous Image Formation with Radio Telescopes

Simultaneous multicolor image formation with a single diffractive optical element.

A design for a novel diffractive optical element (DOE) that can reconstruct three different intensity patterns when it is illuminated by three different wavelengths is presented. If the chosen wavelengths are red, green, and blue, full-color reconstruction capability is obtained. Reconstruction is achieved in the near field (Fresnel domain). Computer simulation results as well as experimental e...

Fish-Eye Observing with Phased Array Radio Telescopes

Radio telescopes of large resolving power.

It was not until 1958 that It could be shown with some certainty that most of the radio sources were powerful extragalactic objects, but the possi­ bilities were so exciting even in 1952 that my colleagues and I set about the task of designing instruments capable of extending the observation to weaker and weaker sources, and of exploring their internal structure. Early observations of radio sou...

Surface figure measurements of radio telescopes with a shearing interferometer.

A new technique for determining the surface figure of large submillimeter wavelength telescopes is presented, which is based on measuring the telescope's focal plane diffraction pattern with a shearing interferometer. In addition to the instrumental theory, results obtained using such an interferometer on the 10.4-m diam telescope of the Caltech Submillimeter Observatory are discussed. Using wa...

Magnetic fields in nearby galaxies: prospects with future radio telescopes

The origin of magnetic fields in the Universe is an open problem in astrophysics and fundamental physics. Our present-day knowledge is limited to regions of strong magnetic fields and to starforming disks of galaxies. Cosmic-ray electrons emitting at high (GHz) radio frequencies can propagate only a few kpc from their places of origin due to their lifetime limited by energy losses. Low-energy e...