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Related papers: Circularly Symmetric Apodization via Starshaped Ma…

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In principle, suppression of on-axis stellar light by a coronagraph is easier on an unobscured aperture telescope than on one with an obscured aperture. Recent designs such as the apodized pupil Lyot coronagraph, the `band-limited' Lyot…

Astrophysics · Physics 2009-11-13 Anand Sivaramakrishnan , James P. Lloyd

In this paper we present the first on-sky results with the fibered aperture masking instrument FIRST. Its principle relies on the combination of spatial filtering and aperture masking using single-mode fibers, a novel technique that is…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 E. Huby , G. Perrin , F. Marchis , S. Lacour , T. Kotani , G. Duchêne , E. Choquet , E. L. Gates , J. M. Woillez , O. Lai , P. Fédou , C. Collin , F. Chapron , V. Arslanyan , K. J. Burns

Weakly supervised methods usually generate localization results based on attention maps produced by classification networks. However, the attention maps exhibit the most discriminative parts of the object which are small and sparse. We…

Computer Vision and Pattern Recognition · Computer Science 2018-08-07 Xiaolin Zhang , Yunchao Wei , Guoliang Kang , Yi Yang , Thomas Huang

Camera calibration is fundamental to 3D vision, and the choice of calibration pattern greatly affects the accuracy. To address aberration issue, star-shaped pattern has been proposed as alternatives to traditional checkerboard. However,…

Computer Vision and Pattern Recognition · Computer Science 2025-05-13 Zezhun Shi

We present yet another new family of masks for high-contrast imaging as required for the to-be-built terrestrial planet finder space telescope. The ``best'' design involves a square entrance pupil having a 4-vane spider, a square…

Astrophysics · Physics 2009-11-10 Robert J. Vanderbei , N. Jeremy Kasdin , David N. Spergel

In this paper, we introduce and explore a new class of starlike functions denoted by $\mathcal{S}^*_{\mathfrak{B}}$, defined as follows: $$\mathcal{S}^*_{\mathfrak{B}}=\{f\in \mathcal{A}:zf'(z)/f(z)\prec…

Complex Variables · Mathematics 2024-03-22 S. Sivaprasad Kumar , Pooja Yadav

We introduce polystar bodies: compact starshaped sets whose gauge or radial functions are expressible by polynomials, enabling tractable computations, such as that of intersection bodies. We prove that polystar bodies are uniformly dense in…

Optimization and Control · Mathematics 2025-06-02 Chiara Meroni , Jared Miller , Mauricio Velasco

Aims. We present pyUPMASK, an unsupervised clustering method for stellar clusters that builds upon the original UPMASK package. Its general approach makes it plausible to be applied to analyses that deal with binary classes of any kind, as…

Astrophysics of Galaxies · Physics 2021-06-16 M. S. Pera , G. I. Perren , A. Moitinho , H. D. Navone , R. A. Vazquez

One of two approaches to implementing NASA's Terrestrial Planet Finder is to build a space telescope that utilizes the techniques of coronagraphy and apodization to suppress diffraction and image exo-planets. We present a method for…

Astrophysics · Physics 2009-11-07 R. Gonsalves , P. Nisenson

We prove a result about producing new frames for general spline-type spaces by piecing together portions of known frames. Using spline-type spaces as models for the range of certain integral transforms, we obtain results for time-frequency…

Classical Analysis and ODEs · Mathematics 2015-04-27 José Luis Romero

High contrast coronagraphic imaging is challenging for telescopes with central obstructions and thick spider vanes, such as the Subaru Telescope. We present in this paper the first laboratory demonstration of a high efficiency PIAA-type…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Julien Lozi , Frantz Martinache , Olivier Guyon

In recent years, there has been a proliferation of wide-field sky surveys to search for a variety of transient objects. Using relatively short focal lengths, the optics of these systems produce undersampled stellar images often marred by a…

Astrophysics · Physics 2009-11-13 Fang Yuan , Carl W. Akerlof

Weak gravitational lensing by the large scale structure can be used to probe the dark matter distribution in the Universe directly and thus to probe cosmological models. The recent detection of cosmic shear by several groups has…

Astrophysics · Physics 2011-05-23 P. Schneider , L. van Waerbeke , Y. Mellier

A new window to observing individual stars and other small sources at cosmological distances was opened recently, with the detection of several caustic-crossing events in galaxy cluster fields. Many more such events are expected soon from…

Instrumentation and Methods for Astrophysics · Physics 2022-08-15 Ashish Kumar Meena , Ofir Arad , Adi Zitrin

Sensitive measurements of the linearly polarized spectra of stars can be used to deduce geometric properties of their otherwise unresolved circumstellar environments. This paper describes some of the evidence for optical pumping and…

Solar and Stellar Astrophysics · Physics 2015-03-17 J. R. Kuhn , B Geiss , D. M. Harrington

Close binary stars are binary stars where the component stars are close enough such that they can exchange mass and/or energy. They are subdivided into semi-detached, overcontact or ellipsoidal binary stars. A challenging problem in the…

Solar and Stellar Astrophysics · Physics 2020-01-08 Sandip V. George , R. Misra , G. Ambika

We present a comparative study of the manufacture of binary pupil masks for coronagraphic observations of exoplanets. A checkerboard mask design, a type of binary pupil mask design, was adopted, and identical patterns of the same size were…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Keigo Enya , Kanae Haze , Takayuki Kotani , Lyu Abe

Linearly polarized, non-masing, rotational lines have been detected for the first time in the interstellar medium. This effect occurs in molecular clouds with a magnetic field, and traces the field direction, offering an alternative…

Astrophysics · Physics 2009-10-31 J. S. Greaves , W. S. Holland , P. Friberg , W. R. F. Dent

We present a novel method to generate a synthetic distribution of objects (mock) on a spherical surface (i.e. a sky), by using a real distribution. The resulting surrogate map mimics the clustering features of the real data, including the…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-09 M. De Domenico , H. Lyberis

In this paper we are exploring the possibilities of 3D printing in the fabrication of mirrors for astronomy. Taking the advantages of 3D printing to solve the existing problems caused by traditional manufacturing, two proof-of-concept…

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