Related papers: Circularly Symmetric Apodization via Starshaped Ma…
The realization that direct imaging of extrasolar planets could be technologically feasible within the next decade or so has inspired a great deal of recent research into high-contrast imaging. We ourselves have contributed several design…
External occulters, otherwise known as starshades, have been proposed as a solution to one of the highest priority yet technically vexing problems facing astrophysics - the direct imaging and characterization of terrestrial planets around…
In this paper, an alternative to the classical pupil apodization techniques (use of an amplitude pupil mask) is proposed. It is shown that an apodized pupil suitable for imaging of Extrasolar planets can be obtained by reflection of an…
We present the concept of a binary shaped mask coronagraph applicable to a telescope pupil including obscuration, based on previous works on binary shaped pupil mask by \citet{Kasdin2005} and \citet{Vanderbei1999}. Solutions with…
Spectrophotometric stability, which is crucial in the spectral characterization of transiting exoplanets, is affected by photometric variations arising from field-stop loss in space telescopes with pointing jitter or primary mirror…
Motivated by the desire to image exosolar planets, recent work by us and others has shown that high-contrast imaging can be achieved using specially shaped pupil masks. To date, the masks we have designed have been symmetric with respect to…
We present here fully optimized two-dimensional pupil apodizations for which no specific geometric constraints are put on the pupil plane apodization, apart from the shape of the aperture itself. Masks for circular and segmented apertures…
Coronagraphs of the apodized pupil and shaped pupil varieties use the Fraunhofer diffraction properties of amplitude masks to create regions of high contrast in the vicinity of a target star. Here we present a hybrid coronagraph…
Direct detection of extrasolar planets will require imaging systems capable of unprecedented contrast. Apodized pupils provide an attractive way to achieve such contrast but they are difficult, perhaps impossible, to manufacture to the…
With a clear circular aperture, the vortex coronagraph perfectly cancels an on-axis point source and offers a 0.9 or 1.75 lambda/D inner working angle for topological charge 2 or 4, respectively. Current and near-future large telescopes are…
This paper presents a scheme to deal accurately and efficiently with complex angular masks, such as occur typically in galaxy surveys. An angular mask is taken to be an arbitrary union of arbitrarily weighted angular regions bounded by…
We present the results of the first laboratory experiment of checkerboard shaped pupil binary mask coronagraphs using visible light, in the context of the R&D activities for future mid-infrared space missions such as the 3.5 m SPICA…
Several coronagraph designs have been proposed over the last two decades to directly image exoplanets. Among these designs, the vector vortex coronagraphs provide theoretically perfect starlight cancellation along with small inner working…
Direct observation of extra-solar planets (exoplanets) is essential to understand how planetary systems were born, how they evolve, and ultimately, to identify biological signatures on these planets. However, the enormous contrast in flux…
Pupil-mapping is a technique whereby a uniformly-illuminated input pupil, such as from starlight, can be mapped into a non-uniformly illuminated exit pupil, such that the image formed from this pupil will have suppressed sidelobes, many…
We present the fabrication and experimental demonstration of three free-standing binary shaped pupil mask coronagraphs, which are applicable for telescopes with partially obscured pupils. Three masks, designed to be complementary (labeled…
Phase apodization coronagraphs are implemented in a pupil plane to create a dark hole in the science camera focal plane. They are successfully created as "Apodizing Phase Plates" (APPs) using classical optical manufacturing, and as…
The performance of pre-trained masked diffusion models is often constrained by their sampling procedure, which makes decisions irreversible and struggles in low-step generation regimes. We introduce a novel sampling algorithm that works…
Pupil-mapping is a technique whereby a uniformly-illuminated input pupil, such as from starlight, can be mapped into a non-uniformly illuminated exit pupil, such that the image formed from this pupil will have suppressed sidelobes, many…
We estimate the distribution of intrinsic shapes of the APM galaxy clusters from their corresponding distribution of projected shapes. We smooth the discrete galaxy distribution and define the cluster shape by fitting the best ellipse to…