Interferometer - sensitivity trade
Case of faint, diffuse object seen against sky background,e.g. galaxies. How does sensitivity of dilute aperture compare to filled?
RULE 1: For different filled apertures, time for given signal/noise in diffraction limited element is independent of aperture.
RULE 2: For dilute aperture, integration time scales as:
T~4 hours for 5? measure of K=19th mag/arcsec2 (z=3, HDF)
b=baseline, d=single element aperture