S E M I N A R I

Departament d'Astronomia i Astrofísica
Universitat de València

    Radio and Optical Interferometry

Bill Cotton

National Radio Astronomy Observatory, Charlottesville, EE.UU


Seminari del departament d'Astronomia i AstrofĂ­sca

Dimarts 17 juny 2008

16:00


Resum

This talk will cover the basics of astronomical interferometry. The underlying basic physical principles are developed by a comparison of the more widely understood radio interferometry with the use of currently developing optical/IR arrays. The implementation technology and practical constraints of radio and optical/IR interferometry are quite different, largely due to the Heisenberg Uncertainty Principle which imposes a huge sensitivity penalty on the detection of the phase of a photon at high frequencies. This leads to "direct" interferometry in the optical/IR where the photons are first interfered and then the interference pattern detected, and "heterodyne" interferometry in the radio where the electric field of the incoming waves is detected and then fringes formed electronically. These and other practical technical details are explored.