CCD Images (ccd + image)

Distribution by Scientific Domains
Physics and Astronomy75%

Selected Abstracts

An ATCA radio-continuum study of the Small Magellanic Cloud , IV.

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2006
A multifrequency analysis of the N 66 region
ABSTRACT Traditional identification of supernova remnants (SNRs) include the use of radio spectral index, optical spectral studies (including strong [S ii], [N ii], [O i], [O ii] and [O iii] lines) and X-ray co-identifications. Each of these can have significant limitations within the context of a particular SNR candidate and new identification methods are continually sought. In this paper, we explore subtraction techniques by Ye, Turtle and Kennicutt to remove thermal emission estimated from H, flux from radio-continuum images. The remaining non-thermal emission allows the identification of SNRs embedded within these H ii regions. Subtraction images of the N 66 region in the Small Magellanic Cloud (SMC) using H, wide-field optical CCD images from the Curtis Schmidt Telescope and the recent Australia Telescope Compact Array (ATCA)/Parkes radio-continuum (1420, 2370, 4800 and 8640 MHz) data are presented as an example. These show three SNRs (B0057 , 724, B0056 , 724 and B0056 , 725) separated from their surrounding H ii radio emission. 2.3-m dual-beam spectrograph long-slit spectra from selected regions within N 66 suggest the presence of an additional SNR with no radio or X-ray emission. Radio spectral index, [S ii]/H, ratio and archived Chandra images of N 66 combine to give a more coherent picture of this region, confirming B0057 , 724 as an SNR. The N 66 nebula complex is divided into 10 components, composed separately of these SNRs and H ii regions. [source]

A Simple Optical Monitoring Technique for Determining the Geometrical Characteristics of a Plasma Jet

PLASMA PROCESSES AND POLYMERS, Issue 2 2006
Boyan E. Djakov
Abstract Summary: A sensor device is proposed to evaluate the location, size, and shape of a plasma jet. It consists of a small number (e.g., six) of photodetectors arranged in a cross-sectional plane of the jet. Tests of the technique are made by simulations based on CCD images of a plasma jet taken simultaneously from three different angles of view. Photodiode configuration [source]

Cosmic-ray rejection for single spectroscopic CCD images by means of template matching

ASTRONOMISCHE NACHRICHTEN, Issue 7 2009
C. Wang
Abstract This article describes a novel algorithm for cosmic-ray rejection in single spectroscopic CCD images. This algorithm is based on a variation of template matching. It focuses on identifying those pixels belong to spectra, while other conventional algorithms tried to locate the cosmic-ray hits directly. The main principle is applying template matching to find suspicious blocks, which is followed by surface patching to locate the legitimate pixels accurately. Therefore, the rest pixels are the ones corrupted by cosmic-ray hits. Meanwhile, almost all the parameters are automatically extracted from the images. Examples of its performance are given for both simulated and observed images. It shows an advantage of significantly low false alarm rate with relatively high detection rate (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]