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: http://hea-www.harvard.edu/CHAMP/IMAGES_DATA/XRAY/index.html
Дата изменения: Unknown Дата индексирования: Tue Oct 2 07:31:01 2012 Кодировка: Поисковые слова: п п р р р р р р р р р р р р р р |
There are jpeg images of the full field in broad band (B) and of individual chips in each band. The file names are of the format
OBSID{obsid}_ccdid{ccdid}_{energyband}_ext.jpg eg., OBSID00914_ccdid0_B_ext.jpg"ext" indicates that circles plotted in the figure are used for count extraction (i.e., 95% encircled energy)
There are smoothed broad band images of each chip in FITS format.
The source properties table has the following columns:
Plots of count rate vs time for each chip. The average count rate and 3-sigma limits are marked. Points which fall outside the 3-sigma limits are marked by red crosses. The blue line segments at the bottom show the Good Time Interval (GTI).
A color-color plot for sources with more than 50 counts. A grid is overlaid for reference, showing expected positions on the plot for various power-law spectra and absorbing column densities.
srcid = XS{obsid}{energyband}{ccdid}_srcno eg., XS12345B9_001 energy band: B : 0.3 - 8.0 keV S : 0.3 - 2.5 keV S1 : 0.3 - 0.9 keV S2 : 0.9 - 2.5 keV H : 2.5 - 8.0 keV HR = H-S / H+S C21 = -logS2+logS1 C32 = -logH+logS2 netB = srcB - bkgB * barea_ratio error_netB = [ (1.0+sqrt(srcB +0.75))^2 + ((1.0+sqrt(bkgB+0.75))/barea_ratio)^2 ]^0.5 SNR = netB/error_netB rateB = 1000.0 * neB / exposure * [max_ea / mean_ea] [exposure and max_ea from "xfield_exposure"] error_rateB = 1000.0 * error_netB / exposure * [max_ea / mean_ea] (max_ea = maximum effective area for a given CCD) (mean_ea = mean effective area within the source extraction radius determined from an exposure map) HR = netH-netS / netH+netS error_HR = (4.0 / netB**4 * (netS**2 * error_netH**2 + netH**2 * error_netS**2))**0.5 C21 = -log(netS2)+log(netS1) error_C21 = ((1.0/netS1/2.302585*error_netS1)**2 + (1.0/netS2/2.302585*error_netS2)**2)**0.5 C32 = -log(netH)+log(netS2) error_C32 = ((1.0/netS2/2.302585*error_netS2)**2 + (1.0/netH/2.302585*error_netH)**2)**0.5