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Optical interferometry is a powerful technique to achieve high angular resolution. However, its main issue is its lack of sensitivity, compared to other observation techniques. Efforts have been made in the previous decade to improve the…

Instrumentation and Methods for Astrophysics · Physics 2022-08-30 Cyprien Lanthermann , Theo ten Brummelaar , Peter Tuthill , Marc-Antoine Martinod , E. Robert Ligon , Douglas Gies , Gail Schaefer , Matthew Anderson

Determining the extrinsic parameter between multiple LiDARs and cameras is essential for autonomous robots, especially for solid-state LiDARs, where each LiDAR unit has a very small Field-of-View (FoV), and multiple units are often used…

Robotics · Computer Science 2022-09-27 Xiyuan Liu , Chongjian Yuan , Fu Zhang

We investigate blending, binarity and photometric biases in crowded-field CCD imaging. For this, we consider random blend losses, which correspond to the total number of stars left undetected in unresolved blends. We present a simple…

Astrophysics · Physics 2009-11-10 L. L. Kiss , T. R. Bedding

Sensor setups consisting of a combination of 3D range scanner lasers and stereo vision systems are becoming a popular choice for on-board perception systems in vehicles; however, the combined use of both sources of information implies a…

Computer Vision and Pattern Recognition · Computer Science 2017-07-28 Carlos Guindel , Jorge Beltrán , David Martín , Fernando García

Accurate alignment of the radio and optical celestial reference frames requires detailed understanding of physical factors that may cause offsets between the positions of the same object measured in different spectral bands. Opacity in…

Astrophysics · Physics 2008-07-21 Y. Y. Kovalev , A. P. Lobanov , A. B. Pushkarev , J. A. Zensus

The Very Small Array (VSA) is a synthesis telescope designed to image faint structures in the cosmic microwave background on degree and sub-degree angular scales. The VSA has key differences from other CMB interferometers with the result…

Vision-Language Models (VLMs) have emerged as the dominant approach for zero-shot recognition, adept at handling diverse scenarios and significant distribution changes. However, their deployment in risk-sensitive areas requires a deeper…

Computer Vision and Pattern Recognition · Computer Science 2024-06-17 Weijie Tu , Weijian Deng , Dylan Campbell , Stephen Gould , Tom Gedeon

A method of absolute calibration for large aperture optical systems is presented, using the example of the Pierre Auger Observatory fluorescence detectors. A 2.5 m diameter light source illuminated by an ultra--violet light emitting diode…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 J. T. Brack , R. Cope , A. Dorofeev , B. Gookin , J. L. Harton , Y. Petrov , A. C. Rovero

We present an assessment of the accuracy of common operations performed in $21$-cm spectral line stacking experiments. To this end, we generate mock interferometric data surveying the 21-cm emission at frequency $1310<\nu<1420$ MHz…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-22 Francesco Sinigaglia , Ed Elson , Giulia Rodighiero , Mattia Vaccari

The calibration and analysis of polarization observations in Very Long Baseline Interferometry (VLBI) requires the use of specific algorithms that suffer from several limitations, closely related to assumptions in the data properties that…

Instrumentation and Methods for Astrophysics · Physics 2021-02-10 Ivan Marti-Vidal , Alejandro Mus , Michael Janssen , Pablo de Vicente , Javier Gonzalez

The implementation of computational sensing strategies often faces calibration problems typically solved by means of multiple, accurately chosen training signals, an approach that can be resource-consuming and cumbersome. Conversely, blind…

Information Theory · Computer Science 2017-02-17 Valerio Cambareri , Laurent Jacques

The Shear TEsting Programme, STEP, is a collaborative project to improve the accuracy and reliability of all weak lensing measurements in preparation for the next generation of wide-field surveys. In this first STEP paper we present the…

Due to the large dynamic ranges involved with separating the cosmological 21-cm signal from the Cosmic Dawn from galactic foregrounds, a well-calibrated instrument is essential to avoid biases from instrumental systematics. In this paper we…

With the availability of thousands of type Ia supernovae in the near future the magnitude scatter induced by lensing will become a major issue as it affects parameter estimation. Current N-body simulations are too time consuming to be…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-10 Valerio Marra , Miguel Quartin , Luca Amendola

In order for Wide-Field Infrared Survey Telescope (WFIRST) and other Stage IV dark energy experiments (e.g., Large Synoptic Survey Telescope; LSST, and Euclid) to infer cosmological parameters not limited by systematic errors, accurate…

Strong gravitational lensing of active galactic nuclei (AGN) enables measurements of cosmological parameters through time-delay cosmography (TDC). With data from the upcoming LSST survey, we anticipate using a sample of O(1000) lensed AGN…

We present a new empirical method for fitting multicolor light curves of Type Ia supernovae. Our method combines elements from two widely used techniques in the literature: the delta_m15 template fitting method and the Multicolor…

Astrophysics · Physics 2008-11-26 Jose Luis Prieto , Armin Rest , Nicholas B. Suntzeff

Current optical interferometers are affected by unknown turbulent phases on each telescope. In the field of radio-interferometry, the self-calibration technique is a powerful tool to process interferometric data with missing phase…

Optics · Physics 2009-11-13 Serge Meimon , Laurent M. Mugnier , Guy Le Besnerais

Twilight/night sky images are often used for flat-fielding CCD images, but the brightness gradient in twilight/night sky causes problems of accurate flat-field correction in astronomical images for wide-field telescopes. Using data from the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Peng Wei , Zhaohui Shang , Bin Ma , Cheng Zhao , Yi Hu , Qiang Liu
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