Double Fourier Modulation for THz spectral-spatial interferometry

by Giorgio Savini (University College London, UK)

Aula Careri (Dip. di Fisica - Edificio G. Marconi)

Aula Careri

Dip. di Fisica - Edificio G. Marconi

Prompted by the future needs of THz astronomy to achieve high angular observations while performing spectroscopy of the same astronomical sources, spectral-spatial interferometry was first achieved in the Near Infrared. This achievement was followed by others at different wavelengths (optical and mm-wave) and with different technologies as it was recognized that at frequencies much higher than those that could be digitized in a heterodyne system this technique named Double Fourier Modulation would promise substantial gains in delivering good spectral and spatial perfo! rmance. Future space far-infrared observatories will not be able to achieve spatial resolution comparable to their optical space telescope counter parts ~0.1" or that of ground based radio interferometers due to the limitation imposed by diffraction limit and by the limited volume of the vector fairing which in turn can accommodate a mirror of limited size.In this seminar I will discuss the spectro-spatial interferometer built with two telescopes at sub-mm wavelengths and first light measurements in the lab and discuss future plans for a mid-infrared thermal testbed.