... One important issue for the spectral analysis with X-ray detectors is the treatment of background for extended sources. ... To deal with the particle background (more or less constant outside proton flares), one should assign weights to the reference event list and extract images or spectra using the same spectral or spatial (in detector coordinates) selection as the source. The original spatial selection (on the source) is usually applied to sky coordinates (not detector coordinates). ...

Next: Background Definition Up: Echelle Spectra Previous: Order Definition . ... Their removal is a rather delicate step, because in high-contrast images (such as well-exposed echelle spectra) there is always a danger of damaging the scientific contents of the frame. Particle hits can be removed from scientific exposures by splitting the exposure and comparing spectra of the same target obtained under the same instrumental configuration. ... Note that the background has been subtracted already. ...

Next: Error Determination Up: *qpspec* - Extraction of Previous: Spectral Extraction of Extended . Charged particles can be removed from the source and background spectra using the master veto (MV) rate. ... For example, if MV rate = 100, the following command will remove the charged particles in the background and source spectra before determining the net spectrum. xs > qpspec vign_corr=yes avg_mvr=100 . ...

... Limitations on the Calibration Accuracy for COS/FUV Observations of Extended Targets and for COS/FUV BOA Observations in Cycle 23 . ... Cycle 23 Results . ... Extended targets with COS/FUV . ... Combined with the aperture vignetting, these effects may result in an unreliable flux calibration for COS/FUV/LP3 observations of extended targets (larger than 0.6? ... Users should make themselves aware of the limitations in the calibration of COS/FUV observations of extended targets or with the BOA at LP3....

This page will present a review with brief descriptions (incl. refs) of different methods. differential equation methods: . ... extended boundary condition method (EBCM): . homogeneous and multilayered) spheres, finite cylinders, spheroids, Chebyshev particles and so on, incl. non-axisymmetric particles (refs) . ... Rayleigh one (conditions + refs) . Rayleigh-Gans one (conditions + refs) . Anomalous Diffraction one (conditions + refs) . Geometrical Optics one (conditions + refs) . ...

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 . ...

... self-absorption - the absorption of light shining on an object by a process similar to that which produced the light originally; if a cloud emits less light than it absorbs from other clouds behind it, this net loss of light, termed self-absorption , causes the foreground cloud to appear darker than the background field (the term is from spectroscopy, where small absorption dips sometimes occur in larger emission lines, making the latter look as if it is absorbing part of itself) . ... HISA Main ...

Proceedings of the Particle Physics and Early Universe Conference (PPEUC). ... M.P. Hobson & A.W. Jones . ... A maximum entropy method (MEM) is presented for separating the emission due to different foreground components from simulated satellite observations of the cosmic microwave background radiation (CMBR). In Jones & Hobson (1998, these proceedings) , the method is applied to simulated observations by the proposed Planck Surveyor satellite. ... 1 Introduction . ... PPEUC Proceedings . ...

... Duchamp | ... Top | Duchamp is a solution to this problem of three-dimensional source finding. ... A list of the detections and their properties, as well as the input parameters that were used. [text file] . ... It can be downloaded in source format, in a gzipped tar archive. ... Changes from the previous version can be seen here (this file is included in the tar archive), while the archive files and documentation from the previous release versions are here , if you are really interested. ...

IRAF/STECF 2-D spectrum point source / background decomposition package . ... The general problem is one of spectral decomposition - of separating the spectra of the point sources from the background. ... The STECF IRAF layered package "specres" provides two tasks to extract point source spectra from 2-D images (either longslit, multislit or cross-dispersed) and decompose the full background over the image. ... A Point Source Function spectrum image is required as a 2-D spectrum. ...

This diagram shows the effect of the 'separate' value of the 'border-collapse' property. The diagram shows a three column, two row table whose cells are subject to the separated borders model. The cells themselves have a grey background color and an 'inset' border style, which makes them appear to sink into the page. ... The table itself has a 10pt 'outset' border that gives one the impression the table is rising out of the page. ...

... public class EDM . ... Euclidean Distance Map: The value of each pixel is the distance to the nearest background pixel (for background pixels, the EDM is 0) - Ultimate Eroded Points (UEPs) are maxima of the EDM. ... static int . ... Unit in old make16bitEDM: this pixel value corresponds to a distance of one pixel. static int . ... int . ... For compatibility with previous versions of ImageJ only. public FloatProcessor makeFloatEDM ( ImageProcessor ip, int backgroundValue, boolean edgesAreBackground)...

... In brief: the frequency-dependent radiative transfer equation is solved for a dust under assumption of spherically-symmetric geometry for its distribution taking into account particle size distribution and quantum heating effects for the very small dust particles. ... Table: Model parameters for IRAS04296+3429. ... parameter . ... hot dust shell) . ... The best fit to the spectral energy distribution of IRAS04296 is shown by heavy solid line (see Table2 for details concerning parameters of the model...

Fermions (particles that obey Fermi statistics) come in generations with each generation heavier than the preceding one. electron neutrinos interact with protons and neutrons; in the early universe this set of reactions keeps the protons and neutrons in balance: . ... Let's assume that the Universe, for no apparent reason, knows about these three constants at arbitrarily early times: . ... However, in the early universe there is an additional source of "pressure" and that is radiation pressure. ...

... Moscow, Russia E-mail: krivosheev@iki.rssi.ru Notes: · · The Monte Carlo method (s) is also called the statistical test method An innumerable number of processes can be listed the outcome of which is not determined and has probabilistic nature, but these processes obey statistical laws, so to obtain the result we have to make multiple similar tests, i.e. to use the MC method Because probabilistic processes are widely spread in nature, the MC ...

Next: Critical Frequencies and Gravitational Previous: Extragalactic Gravitational Wave Background . The number of binaries per frequency decade per solid angle from a separate stellar system (galaxy or cluster of galaxies) is . ... For example, for the Andromeda galaxy M31 ( rad, ) one gets . ... If the angular size of the galaxy is less than the angular resolution of the detector, the critical frequency is independent of the angular resolution, . ...

... Observations of precipitating (Jp) and trapped (Jt) energetic (> 30 keV) particle fluxes at the ionospheric altitudes within the auroral oval region has revealed the existence of a sharp boundary separating the poleward zone of isotropic precipitation (Jp = Jt) from the equatorward zone of weak loss cone filling (Jp << Jt) at all local times (Sergeev and Malkov, 1988). ... boundaries for higher energy particles are located at lower latitudes than boundaries for lower energy particles . ...

... 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. ...

... The Swift X-ray Cluster Survey (SXCS) is an ongoing project aimed at finding serendipitously galaxy clusters in the Swift X-ray Telescope (XRT) archive. ... ROSAT . ... 600 km Here SXCS is compared with other X-ray cluster surveys based on Chandra or XMM data (please refer to Tundo et al. 2012 for detailed discussion). ... We are currently working to a second data release, based on a larger set of XRT fields, and on the use of a Voronoi-based algorithm "EXSdetect" tailored to the XRT data. ...

Disastrous earthquakes happen 100 to 200 times a year. ... There is a chance that the data of ionospheric plasma observations hold an answer to the latter question. Satellites and ground-based facilities may detect earthquake precursors in the ionosphere a few hours or days before the main shock. ... ULF "Hz"-oscillations have been recorded several hours before the main shock in a narrow magnetic field tube (40...100 km along the satellite trajectory) conjugated with epicenter of the earthquake. ...