... QSO spectra in the ROSAT band are steeper than the background at harder energies, and furthermore at fluxes below 1E-14 ergs/(s cmќ) the quasar source counts flatten off and are replaced by more numerous populations of relatively low red-shift objects, apparently Narrow Emission Line Galaxies (NELG). ... We extracted the luminosity function from ROSAT Deep Survey results, and extrapolated by a factor of 2 - 3 to account for changes expected in the harder XMM band. ...

Photon Scattering: Basic Principle of Photon Scattering . Audio Narration is available . No Scattering: Photon Source and Detector . ... For optical photons, scattering goes as wavelength to the -4 power. In the case of blue photons compared to red photons, this means that blue photons are about 10 times more likely to get scattered than red photons. ... Watch the blue photons scatter away from the detector . ... Interstellar dust make stars appear redder than they really are . ...

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. ...

... Data . ... In general, Dolphin finds good agreement with the Whitmore, Heyer, and Casertano results, and the longer baseline and more extensive data set used by Dolphin result in less scatter in the residuals. ... In these case the Dolphin corrections are larger than the Whitmore et al. corrections. ... Figure 1 shows the ratio of counts from a 14 second exposure of Omega Cen in August, 2000 to the counts in a 100 second exposure, vs. the Y position on the chip (WF2 in this case with gain=15). ...

... User Guide ] Task: gpnorm Purpose: Correct the polarisation leakage terms for an offset. Categories: calibration GpNorm is a MIRIAD task which corrects gains and polarisation leakage tables for XYphase and leakage offsets. ... GpNorm compares the leakage terms with nominally correct terms, and determines an leakage and XY phase offset to add which will minimise the difference between the two sets of leakages. ... No default. Key: cal The data-set containing the nominally correct leakage table. ...

... Exposure Time Calculator (ETC) . Survey processing . ... VISTA is a 4-m class wide field survey telescope for the southern hemisphere, equipped with a near infrared camera (1.65 degree diameter field of view at VISTA's nominal pixel size) containing 67 million pixels of mean size 0.34 arcsec and available broad band filters at Z,Y,J,H,K s and a narrow band filter at 1.18 micron. A wide field visible camera, if constructed, could also be used on VISTA. ... Tile . ... ESO VISTA Public Surveys . ...

... Apache HTTP Server Version 2.2 . ... Authorization based on file ownership . ... This module authorizes access to files by comparing the userid used for HTTP authentication (the web userid) with the file-system owner or group of the requested file. ... file-owner . ... The name of the system group that owns the file must be present in a group database, which is provided, for example, by mod_authz_groupfile or mod_authz_dbm , and the web-username must be a member of that group. ... Require file-group...

... Take a particularly simple signal: a cosine wave. ... Now, we are going to stretch and shrink the wavelet along the time axis (we assume the data is in the time domain), and at each time compare the shape of the signal to that of the wavelet. ... Figure 3: The wavelet (dotted line) is translated rela tive to the signal (solid line). ... Figure 4: The dashed line plots the `match' between the wavelets (dotted line) and the signal (solid line) as a function of time. ...

Peremennye Zvezdy", . ... Star Name: . GSC 3710-00312, USNO-A2.0 1425-04252279 . ... Variability type: . ... USNO-A2.0 1425-04252279 is located at the distance of 15?.7 from the X-ray source 1RXS J031707.9+572942, which is larger than the position error of the source (12?), but its hardness ratio HR1 = 0.03 0.29, typical of chromospherically active stars, and its character of variability allow us to assume that the star is related to the X-ray source. ... Eclipsing variability . Sine wave 1 . ...

SAI 175 anniversary . ... Moscow University . Search for in SAI Moscow University Search for in Russian astronomical resources . ... SAI Astronomical Databases . ... Browse SAI Software archive(ftp.sai.msu.su) . ASTRONET.RU - Russian Astronomical Network (available in translit also) . ... SAI Supernovae Research Group . ... Department of the Galaxy and Variable Stars (in Russian) . Sternberg Astronomical Institute Seminars . ... All-Russian Astronomical Olympiad (in Russian) . ...

... We compare our results with the GRANAT X-ray observations of the Galactic center (Churazov et al. ... It is instructive to compare our results for the Galactic center starburst with what might be expected for a continuous star formation, with the average rate characteristic for the whole Galaxy. For this continuous star formation model, we would expect to observe in the region of around the Galactic center about 10% of the total number of X-ray sources in the Galaxy. ...

... Einstein data for SNR are available as images on magnetic tape or diskette and as tables of counting rates. ... In seven cases, with coverage from 35% to 90%, we have calculated an HRI rate for the entire SNR by using the observed IPC data and assuming the ratio of HRI to IPC rates was the same for the observed and the unobserved parts of the remnant. ... Positions of the bright bulge sources and remnants in the galactic plane are known and the rates in table 2 are free of the effects of these. ...

... L-Wide . ... Receiver History . ... Available Filters: . ... Use with e.g. filter 5) NOTE 2 1120-1220 3 1230-1470 4 1550-1820 5 1100-1800 6 1360-1470 7 1320 hipass NOTE 8 1180-1280 9 1280 hipass (ext Output unit. ... Consequently, the calibration for data collected using the hipass 1320 and the hipass 1370 filters only will be mis-calibrated (i.e. by using the opposite polarisation calibration data). ... It is now possible to select any bandpass filter that is not in the 1320 hipass band. ...

... Problem 5. ... See figure 1 for the light curve of these narrow Nitrogen lines. ... Figure out the behaviour of each parcel of gas, and then add them all up to find the light curve. 5.4 (3pts) Using expression from problem 5.2, derive the expression for the time after SN explosion date, when the first light from the ionised ring reaches Earth. Using the expression from problem 5.2, derive the expression for the time after SN explosion date when the maximum brightness of the ring occurs. ...

... The standard science quicklook processing produces over a dozen sky maps at each downlink, and these maps are automatically searched for potential transient point sources. ... We have found that a heuristic modification of a formula derived by Li & Ma (1983) provides reasonably accurate estimates of p -values for point source detections even for very low p -value detections. ... Case 1u. The most straightforward approach uses the signal , where . ... To get a p -value, use . ...

Next: Identifications and Efficiency Up: THE DEEP X-RAY RADIO Previous: Source Classification . ... For some sources which did not have NVSS positions before the time of optical observations, arcsecond positions from the Texas survey (Douglas et al. 1996) and NED (typically based on VLA data) were used. ... All X-ray/radio sources without counterparts on the survey plates were imaged at either the KPNO 0.9m or the CTIO 0.9m telescopes. ... Previously Identified Sources . Sample Properties . ...

... The hotter the gas, the faster they move, and the more energy each of them holds. The free ions and electrons in a plasma behave the same way. Knowing the temperature of the high atmosphere of Earth, or that of the Sun, we can calculate energies expected of ions and electrons found there. However, ions and electrons actually observed in space are often much , much more energetic, and may move at a respectable fraction of the velocity of light (300,000 km/sec or 186,000 miles/sec). ...

2014 May version . ... Green D. A., 2014 , Bulletin of the Astronomical Society of India, 42 , 47-58. ( .pdf , or arXiv.org:1409.0637 ) If you make use of the detailed version of the catalogue, then plaese also cite: . Green D. A., 2014, `A Catalogue of Galactic Supernova Remnants (2014 May version)' , Cavendish Laboratory, Cambridge, United Kingdom (available at "http://www.mrao.cam.ac.uk/surveys/snrs/" ). ... Copyright D. A. Green 2014. 25872nd access to this version of the catalogue. ...

STEP INTO THE BLUE - MEADE INSTRUMENTS PRODUCT GUIDE . ... Telescopes . LX850 Series . ... Superb optical performance coupled with time proven computerized pointing and tracking has made the LX200 ACF series a best-seller in the high-performance telescope class. ... Meade's revolutionary LS LightSwitchтДв series of telescopes use advanced technologies to do what no other consumer telescopes have done before: take all the hassle out of using a telescope. ... PST . ... Hard case for PST . ...

... The sample of the Local Volume galaxies (distance smaller than 10 Mpc) gives a unique opportunity to study the properties of galaxies including the weakest objects: the absolute magnitude M B -10 and the virial mass M vir 10 9 M x263C;. ... Luminosity function of the Local Volume galaxies. ... The luminosity functions for galaxies are presented: red dashed line - from the 2dFGRS survey (Norberg et al. 2002); blue dash-dotted line - from the SDSS survey (Blanton et al. ...