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Дата изменения: Tue Nov 23 00:04:58 2004
Дата индексирования: Sat Dec 22 09:28:07 2007
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XMM-Newton Science Analysis System


omdetect (omdetect-4.19.5) [xmmsas_20041122_1834-6.1.0]

Meta Index / Home Page

SourceListFile

• COLUMN NO NAME UNITS DESCRIPTION
• 1 SRCNUM none

• 2 XPOS pixels x-coordinate of centroided source centre
• 3 YPOS pixels y-coordinate of centroided source centre
• 4 POSERR pixels error in x and y centroided position
• 5 RATE counts/sec Total measured source counts within measurement aperture divided by exposure time
• 6 RATE_ERR counts/sec
• 7 BACKGROUND_RATE counts/sec Total measured background counts within measurement aperture divided by exposure time
• 8 SIGNIFICANCE sigma source counts / sqrt(background counts) (ie signal-to-noise ratio)
• 9 CORR_RATE counts/sec RATE after extrapolating (if neccesary) to an aperture radius of 12 unbinned pixels and correcting for coincidence losses.
• 10 CORR_RATE_ERR counts/sec
• 11 CORR_BACKGROUND_RATE counts/sec BACKGROUND_RATE after extrapolating (if neccesary) to an aperture radius of 12 unbinned pixels and correcting for coincidence losses.

• 12 PSF1_CORR percentage Point-spread function correction applied to extrapolate RATE from measurement aperture area to area of 12 unbinned pixels
• 13 COINCLOSS_CORR percentage Coincidence-loss correction applied - (RATE - CORR_RATE) * 100.0 / RATE
• 14 NOPIXELS none Number of pixels contained by an extended source (EFLAG=1). Point-sources (EFLAG=1) will have this value set to zero.
• 15 APERTURE unbinned pixels For point sources (EFLAG=0), the aperture radius (unbinned pixels) used in the photometry. For extended-sources (EFLAG=1) this value will be set to NULL.
• 16 FWHM_MAJ arcsecs The full-width-at-half-maximum of the semi-major of the ellipse describing the shape of the source (computed by moments)
• 17 FWHM_MIN arcsecs The full-width-at-half-maximum of the semi-major of the ellipse describing the shape of the source (computed by moments)
• 18 PA degrees The postion-angle (referred to the x-axis) of the semi-major of the ellipse describing the shape of the source (computed from moments)
• 19 QFLAG none (source quality flag) Can be either 0 or 1. Set to 0 if all the image pixels used to obtain the counts for the source were good, 1 otherwise.
• 20 CFLAG none (source confusion flag) Can be either 1, 2, 3 or 4. 1 means that the nearest source is at a distance of greater than twice the aperture radius. 2 means that there are one or more sources within a distance of twice the aperture radius, but at a distance greater than the aperture radius. 3 means that there are one or more sources within a distance of the aperture radius. 4 means that the source lies near an edge of the image

• 21 EFALG none (source extension flag) Either 0 point-source (none-extended) or 1 extended.