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Related papers: Cosmic Ray Removal in Fiber Spectroscopic Image

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We present a method for detecting cosmic rays in single images. The algorithm is based on simple analysis of the histogram of the image data and does not use any modeling of the picture of the object. It does not require a good signal to…

Astrophysics · Physics 2009-11-10 Wojtek Pych

We present a convolution-based algorithm for finding cosmic rays in single well-sampled astronomical images. The spatial filter used is the point spread function (approximated by a Gaussian) minus a scaled delta function, and cosmic rays…

Astrophysics · Physics 2009-10-31 James E. Rhoads

Conventional algorithms for rejecting cosmic-rays in single CCD exposures rely on the contrast between cosmic-rays and their surroundings, and may produce erroneous results if the Point Spread Function (PSF) is smaller than the largest…

Astrophysics · Physics 2011-08-01 Pieter G. van Dokkum

As a space telescope, the China Space Station Survey Telescope (CSST) will face significant challenges from cosmic ray (CR) contamination. These CRs will severely degrade image quality and further influence scientific analysis. Due to the…

Instrumentation and Methods for Astrophysics · Physics 2025-11-04 Yan Yu , Bin Ma , Tianmeng Zhang , Yi Hu , Yajie Zhang

We present an algorithm to optimally process uniformly sampled array image data obtained with a nondestructive readout. The algorithm discards full wells, removes cosmic ray (particle) hits and other glitches, and makes a nearly optimum…

To maximise data output from single-shot astronomical images, the rejection of cosmic rays is important. We present the results of a benchmark trial comparing various cosmic ray rejection algorithms. The procedures assess relative…

Astrophysics · Physics 2009-11-13 Catherine L. Farage , Kevin A. Pimbblet

Cosmic rays are a known problem in astronomy, causing both loss of data and data inaccuracy. The problem becomes even more extreme when considering data from a high-radiation environment, such as in orbit around Earth or outside the Earth's…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 Rachel E. Anderson , Karl D. Gordon

Due to limited size and imperfect of the optical components in a spectrometer, aberration has inevitably been brought into two-dimensional multi-fiber spectrum image in LAMOST, which leads to obvious spacial variation of the point spread…

Instrumentation and Methods for Astrophysics · Physics 2020-10-28 Jiali Xu , Qian Yin , Ping Guo , Xin Zheng

The results of recognition of cosmic ray (CR) signatures on a single image were analyzed for several codes written by several authors. For most visual images made during low solar activity at exposure time t>4 s, the number of clusters of…

Astrophysics · Physics 2008-11-26 S. I. Ipatov , M. F. A'Hearn , K. P. Klaasen

A cosmic ray observatory with full-sky coverage can exploit standard anisotropy analysis methods that do not work if part of the celestial sphere is never seen. In particular, the distribution of arrival directions can be fully…

Astrophysics · Physics 2009-10-31 Paul Sommers

In the last years the direct measurement of cosmic rays received a push forward by the possibility of conducting experiments on board long duration balloon flights, satellites and on the International Space Station. The increase in the…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Emiliano Mocchiutti

We examine cosmic ray rejection methodology on data collected from InSb and Si:As detectors. The application of an Up-the-Ramp sampling technique with cosmic ray identification and mitigation is the focus of this study. This technique is…

The sky subtraction performances of multi-fiber spectrographs are discussed, analysing in detail the case of the OPTOPUS system at the 3.6 meter ESO telescope at La Silla. A standard technique, based on flat-fields obtained with a uniformly…

Astrophysics · Physics 2009-10-22 C. Lissandrini , S. Cristiani , F. La Franca

We describe a new algorithm for the "perfect" extraction of one-dimensional spectra from two-dimensional (2D) digital images of optical fiber spectrographs, based on accurate 2D forward modeling of the raw pixel data. The algorithm is…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Adam S. Bolton , David J. Schlegel

Astronomical images often show sharp features that are caused by cosmic ray (CR) hits, hot pixels, or non-Gaussian noise. L.A.Cosmic (van Dokkum 2001) is a widely used edge detection algorithm that identifies and replaces such features.…

Instrumentation and Methods for Astrophysics · Physics 2026-02-23 Carter Lee Rhea , Pieter van Dokkum , Steven R. Janssens , Imad Pasha , Roberto Abraham , William P. Bowman , Deborah Lokhorst , Seery Chen

Traditional cosmic ray filtering algorithms used in X-ray imaging detectors aboard space telescopes perform event reconstruction based on the properties of activated pixels above a certain energy threshold, within 3x3 or 5x5 pixel sliding…

Cosmic ray astronomy attempts to identify and study the sources of ultrahigh energy cosmic rays. It is unique in its reliance on charged particles as the information carriers. While no discrete source of ultrahigh energy cosmic rays has…

Astrophysics · Physics 2010-01-15 Paul Sommers , Stefan Westerhoff

We propose easy ways of correcting for the systematic errors caused by the photon noise and the pixelation effect in cosmic shear measurements. Our treatment of noise can reliably remove the noise contamination to the cosmic shear even when…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-16 Jun Zhang

Photometric surveys have provided incredible amounts of astronomical information in the form of images. However, astronomical images often contain artifacts that can critically hinder scientific analysis by misrepresenting intensities or…

Instrumentation and Methods for Astrophysics · Physics 2020-06-03 Suchetha Cooray , Tsutomu T. Takeuchi , Moe Yoda , Kazuo Sorai

Reviews statistical methods for 1- and 2-dimensional analysis of cosmic ray data including recent Bayesian analyses.

Astrophysics · Physics 2009-10-31 K. J. Orford
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