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Related papers: Positioning errors and efficiency in fiber spectro…

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The performance of highly-multiplexed spectrographs is limited by focal degradation (FRD) in the optical fibres. It has already been shown that this is caused mainly by processes concentrated around the mounting points at the ends of the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Jeremy Allington-Smith , Colin Dunlop , Graham Murray , Ulrike Lemke

For fiber-fed spectrographs with a stable external wavelength source, scrambling properties of optical fibers and, homogeneity and stability of the instrument illumination are important for the accuracy of radial-velocimetry. Optical…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 I. Boisse , F. Bouchy , B. Chazelas , S. Perruchot , F. Pepe , C. Lovis , G. Hebrard

The influence of low-spatial frequency errors of an optical component of an imaging system on the point spread function can be quantified using Zernike polynomials. High-spatial frequency errors cause strong scattering due to which the…

Optics · Physics 2026-04-03 Luuk Zonneveld , Paul Urbach , Aurèle Adam

The current methods available to estimate gravitational shear from astronomical images of galaxies introduce systematic errors which can affect the accuracy of weak lensing cosmological constraints. We study the impact of KSB shape…

We study the impact of systematic errors on planned weak lensing surveys and compute the requirements on their contributions so that they are not a dominant source of the cosmological parameter error budget. The generic types of error we…

Astrophysics · Physics 2010-04-06 Dragan Huterer , Masahiro Takada , Gary Bernstein , Bhuvnesh Jain

Wide field-of-view (FOV) cameras, which capture a larger scene area than narrow FOV cameras, are used in many applications including 3D reconstruction, autonomous driving, and video surveillance. However, wide-angle images contain…

Computer Vision and Pattern Recognition · Computer Science 2021-12-02 Jinlong Fan , Jing Zhang , Stephen J. Maybank , Dacheng Tao

Many lens surveys have hitherto used observations of large samples of background sources to select the small minority which are multiply imaged by lensing galaxies along the line of sight. Recently surveys such as SLACS and OLS have…

Astrophysics · Physics 2008-11-26 N. Jackson , I. W. A. Browne

The ambitious science goals of the Large Synoptic Survey Telescope (LSST) have motivated a search for new and unexpected sources of systematic error in the LSST camera. Flat-field images are a rich source of data on sensor anomalies,…

Instrumentation and Methods for Astrophysics · Physics 2015-04-24 Michael Baumer , Aaron Roodman

The knowledge of the exact structure of the optical system PSF enables a high-quality image reconstruction in fluorescence microscopy. Accurate PSF models account for the vector nature of light and the phase and amplitude modifications.…

In this work, we present an analysis of the influence of the geometrical parameters on the sensitivity and linear range of the fiber optic angular displacement sensor, through computational simulations and experiments. The geometrical…

Deterministic sources of quantum light are becoming increasingly relevant in the development of quantum communication, particularly in deployed fiber networks. Therefore, efficient fiber-coupled sources at telecom wavelength are highly…

Scientists use imaging to identify objects of interest and infer properties of these objects. The locations of these objects are often measured with error, which when ignored leads to biased parameter estimates and inflated variance.…

This paper addresses the issue of detecting point objects in a clutter background and estimating their position by image processing. We are interested in the specific context where the object signature significantly varies with its random…

Applications · Statistics 2009-11-09 Vincent Samson , Frédéric Champagnat , Jean-François Giovannelli

The extraction of fibers from dMRI data typically produces a large number of fibers, it is common to group fibers into bundles. To this end, many specialized distance measures, such as MCP, have been used for fiber similarity. However,…

Computer Vision and Pattern Recognition · Computer Science 2017-09-20 Kuldeep Kumar , Pietro Gori , Benjamin Charlier , Stanley Durrleman , Olivier Colliot , Christian Desrosiers

Optimizing on-sky single-mode fiber (SMF) injection is an essential part of developing precise Doppler spectrometers and new astrophotonics technologies. We installed and tested a prototype SMF injection system at the Large Binocular…

Instrumentation and Methods for Astrophysics · Physics 2020-05-22 Andrew J. Bechter , Jonathan Crass , Jonathan Tesch , Justin R. Crepp , Eric B. Bechter

Despite their ability to represent highly expressive functions, deep learning models seem to find simple solutions that generalize surprisingly well. Spectral bias -- the tendency of neural networks to prioritize learning low frequency…

Machine Learning · Computer Science 2022-09-30 Sara Fridovich-Keil , Raphael Gontijo-Lopes , Rebecca Roelofs

The constructive and destructive interference in different layers of the James Webb Space Telescope (JWST) Mid-Infrared Instrument (MIRI) detector arrays modulate the detected signal as a function of wavelength. Additionally, sources of…

Systems in nature are stochastic as well as nonlinear. In traditional applications, engineered filters aim to minimize the stochastic effects caused by process and measurement noise. Conversely, a previous study showed that the process…

Systems and Control · Electrical Eng. & Systems 2024-07-11 Burak Boyacıoğlu , Mahnoush Babaei , Amanuel H. Mamo , Sarah Bergbreiter , Thomas L. Daniel , Kristi A. Morgansen

Most studies that consider the problem of estimating the location of a point source in wireless sensor networks assume that the source location is estimated by a set of spatially distributed sensors, whose locations are fixed. Motivated by…

Information Theory · Computer Science 2016-11-18 Mohammad Fanaei , Matthew C. Valenti , Natalia A. Schmid

Focal Ratio Degradation (FRD) in fibres is a crucial factor to control in astronomical instruments in order to minimize light loss. As astronomical instrumentation has advanced, the integration of large populations of fibres has become…

Instrumentation and Methods for Astrophysics · Physics 2023-06-30 Weimin Sun , Xudong Chen , Jiabin Wang , Hang Jiang , Anzhi Wang , Qi Yan , Zhenyu Ma , Shengjia Wang , Tao Geng , Yue Zhong , Zhongquan Qu , Yunxiang Yan