... 172 ] Briefly, the count rate at the detector from a source at a redshift z is . ... Figure 55 shows the ``Green functions'' for the double compact binary merging rate   evolution assuming no collapse anisotropy. ... Another way that diverse peculiarities in the - distribution induced by the sources evolution could arise is connected with a possible non-monotonic character of the star formation rate in galaxies. ... 22 ] Figure  56 shows two-dimensional cuts through the parameter space. ...

... 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. ...

... GPI Data Pipeline 1.0 documentation . ... Thermal/Sky Backgrounds . ... Using Thermal/Sky Backgrounds in GPI Data Reduction: . Creating Calibrations: . ... Thermal emission (from sky or telescope) becomes an important background source for wavelengths longer than 2 microns. ... The pipeline treats thermal/sky backgrounds similar to dark frames and is designed to subtract a thermal/sky background, scaled to the integration time of the science image, from K-band observations. ...

Next: Catalog Construction Up: Observations and Analysis Previous: Source Detections . ... It was assumed that the highest signal gives the most likely position of the source. ... Comparing the summed map with the maps from the individual energy ranges, the one which produced the smallest error box was chosen to represent the source position, as long as was greater than 4, a level chosen to reflect a reasonable degree of confidence in the detection. ...

... Where we have just a single image we assume a probabilistic mode of source detection such that, at a given image pixel, if the probability that the observed value at that pixel could have arisen through statistical fluctuation of the background at that pixel lies below a certain limiting probability , the pixel is considered to contain a source. In XMM practice it is likelihood rather than itself which is employed; in this case the detection criterion is for to exceed the cutoff . ...

The process of determining the number and characteristics of sources in astronomical images is so fundamental to a large range of astronomical problems that it is perhaps surprising that no standard procedure has ever been defined that has well understood properties with a high degree of statistical rigour on completeness and reliability. ... In this analysis we present results from testing such algorithms as implemented in the SExtractor, Selavy (Duchamp), and sfind tools on simulated data. ...

... Next: The PROS Big Up: Software Systems Previous: Data Reduction Software . ... The srcinten task provides PROS users with a tool to compute count rates for point sources in the ROSAT High Resolution Imager (HRI). ... Corrected upper limits are cited at locations where the count rate falls below the source detection threshold. ... Srcinten is a new PROS task that computes and applies the above correction factors to the net counts in a user-specified aperture. ...

... Galaxy Evolution home . ... The origin and evolution of radio sources . Radio sources and their environments . ... We are investigating how this interaction effects galaxy evolution in general as well as the feedback effect of the radio source on its host galaxy and AGN. ... One direct observational manifestation of this interaction is the existence of extended regions of emission-line gas which show a clear spatial relationship to the radio source itself. ...

... LABORATORY OF RADIO ASTRONOMICAL OBSERVATIONS . Radio sources identification is one of the most important tasks of the current radio astrophysics. ... Optical idetification. ... Optical identifications of subsample of steep spectra radio sources from RC catalog using 6m SAO telescope of SAO RAS: optical observations. ... Astronomy Reports. ... Identification of radio sources with data of various radio catalogs allows one to construct continual spectrum of the object and its radio structure. ...

... The J, H and K bands are characterized by a bright background, such a background is mainly due to the emission of atmospheric lines and of thermal radiation. ... If the source cover a large fraction of the slit, spectra off-source must be observed to adequately sample the sky background. ... The on chip integration time (time spent in each position of the slit) must not exceed 40 seconds in J and H bands and 60 seconds in K band. ... We suggest a sequence of 10 for each elementary integration time. ...

... There is no question about the source of ionospheric plasma , since it is created from the ambient neutral atmosphere by ionization. However, the source of magnetospheric plasma is a much more complicated question: although it seems obvious that both solar wind and ionosphere feed it, the relative importance of these two sources is unclear. ... Protons (H + ) are the primary ions in solar wind and one of the major components in ionospheric outflows, and thus not good indicators of their source. ...

Next: Conclusions Up: Selection Effects Previous: Inconsistent (or Inconsistently Applied) . Another possible bias, present in this as well as all other surveys which use spectral indices based upon nonsimultaneous data in their selection process, is due to variability. ... In order to minimize the effect of non-simultaneous radio survey data upon our samples, we decided to expand the common definition of flat-spectrum radio sources to extend to (instead of 0.5). ...

... a) As source material for the high-school or college curriculum, especially in physics. astronomy and their history. (b) As a source of supplemental projects by high school students or by undergraduates. (c) As material for independent studies, In particular by motivated students who seek to know more about space . ... Those wishing to look up specific topics are advised to use the index file, accessible from the end of any "Exploration" file. ... files not listed and at other resource material. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Quasi-stationary electron distributions for the different values of the particle escape time. ... The electron-cyclotron maser instability is widespread in the Universe, producing, e.g., radio emission of the magnetized planets and cool substellar objects. ... The model used takes into account the radiation escape from the source region and the particle flow through this region. ...

Family ASTRO Event Leaders can follow the links below to find a number of resources and more background reading to help them with their Astronomy Events and expand their knowledge on the topics covered in our series of Leader Kits for educators. ... Print and Web Resources on the Night Sky . ... If you have questions about Family ASTRO, see our Frequently Asked Questions for Educators and Astronomers page , or our Frequently Asked Questions for Families and Friends page. ...

... During the analysis of the surveys carried out on RATAN-600, it was found that almost one fifth of the detected sources shows significant radio flux variations. ... We used the data from "Cold" radio surveys carried out with RATAN-600 in 1980-1994 to search for radio sources with significant flux variability. ... On possibility of detection of variable sources using the data of Cold surveys carried out on RATAN-600. ... Detection of Variable Sources Using the Data of "Cold" Surveys. ...

Links and Resources for Energy and the Environment . The world is finally becoming globally aware that exponential resource usage in combination with finite reserves is a recipe that ensures our great grandchildren won't be born. ... National Environmental Information Service . ... Electronic Energy Journal . ... Sustainable Development Dimensions , including sections on Environmental information , Environmental policy, planning and management and Energy for development . ... Acid Rain Resource . ...

... The VSOP Survey Continuum Source List . The radio sample for the VSOP continuum survey was defined to include all extragalactic radio sources with: . a total flux density at 5 GHz, S>=1.0 Jy . ... The sample also included all sources in the sky with a 5 GHz flux density S>5 Jy, regardless of spectral index and galactic latitude. ... The source would then be included in the VSOP sample (three of the sources were found with a flux density above 1 Jy and added to the sample). ...

In calculating the NIFS sensitivity, we adopt a read noise of 5 e - , a dark current of 0.01 e - s -1 pix -1 , and a maximum exposure time of 3600 s. Grating . ... e/pix) . ... OH Cont. (e/pix) . ... NIFS should achieve signal-to-noise ratios of ~ 10 per spectral pixel in a 0.1" 0.1" aperture for single 1800 s exposures on uniform, extended, continuum sources with surface brightnesses of J = 15.4, J = 15.0, H = 14.8, and K = 13.5 mag arcsec -2 using the Z , J , H , and K gratings, respectively. ...

Plans are under way to create a new way of performing non-interactive observations which will be called auto-observing . ... Non-interactive observing with CIMA has for a long time been available with the use of CIMA command files. Contrary to normal command file observing which requires a command file with a set of commands to be executed sequentially, auto-observing will use a list of sources and a list of instructions on how to observe each of the sources. ...