... This paper describes the main algorithms used by the Einstein Level One processing to create the exposure masks and the background maps for Einstein IPC images, and how these algorithms were recreated in the IRAF environment. Our goal was to recreate the algorithms used by the Level One Processing to create exposure masks and background maps for Einstein Image Proportional Counter (IPC) data (cf. sections 2.5 and 2.7 of Harnden et al. ...

Next: Implementation Up: Compensation for Read-Out Noise Previous: Compensation for Read-Out Noise . Various methods are being used to compensate for the resolution loss that is present in image data acquired by the Hubble Space Telescope. ... There are a variety of noise sources present in HST image data acquired with a CCD camera. ... We use the term background counts for the cumulative effect of these extraneous electrons. Background counts are Poisson distributed. ...

... Meta Index / Home Page / Background image The alogorithm works as follows. Compute the mean value of the whole image, using a clipping algorithm. Divided the image into boxes of size 100 by 100 pixels. For each box . Obtain a list of pixels with a value less than maxheight . loop through all the pixels in the box and obtain a list of the ``usable'' background pixels within a box of size 100 . ... Find the median of the list of pixels and set the background pixel to this value . ...

... RJMCMC Similar to Richardson Green 1997 Knowledge of the PSF makes things easier Insensitive to e.g. posterior for ten sources with = 3: Number of Components 9 10 11 12 0.141 0.222 0.220 0.157 0.022 0.029 0.027 0.021 Mean SD 7 0.029 0.018 8 0.058 0.019 13 0.082 0.014 Simulated Data Source region (2 SD) is about 28% of the area and contains about 41% of the observations Positions (-2, 0), (0, 1), (1.5, 0) with intensities ... Approximate the number of sources (2 in this case) 2. ...

Next: Online Reduction Up: IRAC2 Online and Previous: IRAC2 Online and . In many ways, IR array data is similar to that taken with optical CCDs; however, there are a number of important differences that are mainly due to the large, variable sky and instrumental backgrounds that arise at these longer wavelengths. ... The IRAC2 context in MIDAS includes a number of commands that are most useful at the telescope. ... The IRAC2 context can be activated by the command SET/CONTEXT IRAC2 . ...

Understanding Europa's Radiation Environment and How it Influences Landing Site Characterization G.W. Patterson, L.M. Prockter, C. Paranicas Applied Physics Laboratory Introduction · The surface of Europa is weathered by charged and neutral particles, micrometeroids, and photons. ... Background · Criteria for characterizing potential landing sites [e.g., Figueredo et al., ... 2004) Background · Criteria for characterizing potential landing sites [e.g., Figueredo et al., ... Figueredo et al., ...

SiD Tracking using VXD Nick Sinev, University of Oregon Plan Motivation Track reconstruction algorithm Performance for single tracks Does it have any limits ? With backgrounds To do Motivation Tracking in SiD is a challenge, especially pattern recognition. ... Limitations caused by reconstruction speed consideration In the presence of high number of background hits, number of 3-point combinations used as track seed became enormous if we consider all combinations. ...

Next: Basic Properties Up: R Coronae Borealis Stars Previous: Introduction . RCB stars are named after a star just visible to the naked eye in the constellation of Corona Borealis. RCrB was discovered by Edward Pigott, an English amateur astronomer, who had been observing a star in the `Northern Crown' for over a decade. ... Since 1795, other RCB stars have been discovered and their properties have been carefully observed. ...

T he Siding Spring Survey (SSS) is a Near-Earth Object search program that utilises the 0.5-m Uppsala Schmidt Telescope at Siding Spring Observatory, N.S.W., Australia. ... The mission of the Siding Spring Survey is to contribute to the inventory of near-earth objects (NEOs), or more specifically, the potentially hazardous asteroids (PHAs) and comets (PHOs) that may pose a threat of impact and thus harm to civilization. ... Based on the CSS Mission page . ... Siding Spring Survey Main Page . ...

Next: The STScI NICMOS Calibration Up: No Title Previous: CONICA: The high resolution . The STScI NICMOS Calibration Pipeline . Introduction . ... Dark Current Subtraction . ... Input Data . ... Scalar Background Subtraction . 2-D Background Subtraction . ... Status and Goals of the NICMOS Calibration Plan . ... Photometry . ... Photometric Performance of NICMOS . ... NICMOS Photometry. ... ST-ECF Grism Spectrum Software for NICMOS Grism Data . ... Analysis . ... STScI NICMOS Software . ...

Creating A Drop Shadow . This is our layer of text. Try clicking on the little eye icon in the background layer. ... When you're finished experimenting, make sure to highlight the text layer again. ... Gaussian Blur (either IIR or RLE is fine). The default value of 5.0 produces a nice, fuzzy blur. Fuzzy layer below the solid one . Offset, and offset the blurred layer 2x and 2y. See how it makes the shadow stand out? ... Our layered, drop-shadowed text . Step 1 | ...

View Edit Attributes History Attach Print Search . ... Science . ... Observing . ... Internal . ... Editing this wiki . ... The aim of this document will be to describe to non pulsar astronomers the science obtainable from the PPTA and related projects . The Parkes pulsar timing array (PPTA) has three main aims. ... The purpose here is to document the scientific results being obtained by the PPTA (and other related timing array projects) in a way that is understandable to non-pulsar astronomers. ...

... Using the DRAO Synthesis Telescope (Landecker et al. 2000), the Canadian Galactic Plane Survey ( CGPS ; Taylor et al. 2002) has captured a multitude of HISA features, the majority of which are invisible in prior surveys at lower resolution. ... Since the HISA gas temperature must be less than the background brightness temperature, all the H I shown in this poster has T ~ 100 K. Figure 1 provides panoramic views of the cold H I visible as HISA in the CGPS. ... GIFs: HISA + CO | HISA only | ...

... Report on Cosmic Call 1999 . ... Cosmic Call Sessions . ... This Report outlines methodology, hard- and software, which were developed to transmit first public Interstellar messages from Evpatoria Deep Space Center (EDSC), and describes four Cosmic Call Sessions, which were fulfilled in EDSC on May 24 and June 30 - July 1, 1999. ... Each Cosmic Call consists of two parts. ... Dutil Message, . ... The software for gathering all messages and creating the Cosmic Call stream, was written on C language. ...

Next: Observational Zoo of Binaries Up: No Title Previous: Contents . In the early 1980s, our understanding of binary star evolution љ based on the pioneer work by Paczynski (1971)[ 150 ], Tutukov and Yungelson (1973)[ 195 ], van den Heuvel and Heise (1972)[ 201 ], allowed us to construct a general evolutionary scenario љ which successfully explained the genesis of well-studied normal stars and offered potential explanation for new X-ray sources discovered in space experiments. ...

Proceedings of the Particle Physics and Early Universe Conference (PPEUC). For this paper: postscript PPEUC CMB index 1 Introduction .. ... A new statistic is discussed, designed to detect isolated coherent step-like discontinuities produced by cosmic strings present at late times. ... The statistical variable considered is the Sample Mean Difference (SMD) between large neighbouring sectors of CMB maps, separated by straight lines in two dimensional maps and points in one dimensional maps. ...

This diagram shows the six superimposed "layers" of the CSS table model. This diagram illustrates the algorithm for calculating a cell's final background. ... The diagram shows how, looking down on the six rectangles, one may compute the background color of each cell. ... A cell without a background color in the top layer is depicted as a "window" onto the lower layers, which give its final background color. ...

... If, like me, you want to really understand your system rather than just knowing how to use it, this document should be a good place to start. ... I hope some readers will undertake the best Linux learning exercise that I know of, which is building a system from source code. ... The instructions that used to be part of this document are now in a separate document ``Building a Minimal Linux System from Source Code'', and can be found at From PowerUp to Bash Prompt home page . ...

... Science Activities > PhD Thesis Topics offered by ESO Faculty Members > Thesis Topic: Foreground emission and Cosmic Microwave background intrinsic anisotropies . ... Since its discovery the Cosmic Microwave Radiation (CMB) has been one of the pillars of modern Cosmology. ... Further development of this work is the application of already tested algorithms to disentangle the foreground emission from the CMB maps and the determination of the CMB intrinsic emission. ... Return to list of thesis topics ...

Geometric group theory is the study of groups from the geometric viewpoint. ... Background from group and graph theories. Word problem. Cayley graphs. The word problem and Cayley graphs. Dehn's solution to the word problem for the hyperbolic surface groups. Coxeter groups. Tits' solution to the word problem for Coxeter groups. Cayley graphs and group actions. ... Introduction to Gromov hyperbolicity. ... P. Scott, T. Wall, Topological methods in group theory, London Math. ...