1 research outputs found
Fringe Visibility Estimators for the Palomar Testbed Interferometer
Visibility estimators and their performance are presented for use with the
Palomar Testbed Interferometer (PTI). One operational mode of PTI is
single-baseline visibility measurement using pathlength modulation with
synchronous readout by a NICMOS-3 infrared array. Visibility is estimated from
the fringe quadratures, either incoherently, or using source phase referencing
to provide a longer coherent integration time. The visibility estimators differ
those used with photon-counting detectors in order to account for biases
attributable to detector offsets and read noise. The performance of these
estimators is affected not only by photon noise, but also by the detector read
noise and errors in estimating the bias corrections, which affect the
incoherent and coherent estimators differently. Corrections for visibility loss
in the coherent estimators using the measured tracking jitter are also
presented.Comment: PASP in press (Jan 99). 13 Pages, no figure