Experimental Progress and Results of a Visible Nulling Coronagraph

摘要: The crux of visible exoplanet detection is overcoming significant star-planet contrast ratios on the order 10-7 to 10-10 - at very small angular separations. We are developing a nulling interferometer coronagraph designed achieve 10-6 ratio working science bandpass 20% light using pseudo-achromatic phase flip. Recent results yield level with 15% averaged over three seconds. Further broadening will require hardware modifications, although argument made that should not adversely affect null depth until beyond light. current testbed configuration has reached monochromatic depths 1.11times10-7 (lambda = 638 nm) This paper describe experimental approach for achieving broadband nulls, as well error considerations and limitations, most recent testbed.