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Дата индексирования: Tue Oct 2 08:04:27 2012
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Поисковые слова: dwarf spheroidal

Quick guide for ChaMPlane Database

Searching sources by coordinates
[left   panel]: select the coordinate 
		(e.g RA=337.3831880°, Dec=61.2185250°, Radius=2′)
[right  panel]: display the results

Browsing by ObsID
[left   panel]: list available observations by ObsID
[middle panel]: list available data product for the selected ObsID
[upper right panel]: list the data by srcid
[lower right panel]: show the data for a selected srcid

Table display option
[rdb]  or [r]: RDB format table (TAB based text table)
[txt]  or [t]: simple text table
[list] or [l]: listing mode, easy to find column definition 
	       and view everything per each item
[html] or [h]: HTML table format
[cust] or [c]: customize output format, allows to choose
	       specific columns and sort by a certain column
[reg]        : region files

Source ID and source name
The chandra sources in ChaMPlane can be uniquely addressed by their
source ID (srcid).  X-ray source ID is defined as XS + x-ray ObsID +
energy band + CCD ID + source number. For example, XS02787B3_015 is
the 15th source in CCD 3 of Obs. ID 2787 detected in B (Bx) band.  
The optical source ID (optid) is defined as OS + optical ObsID +
source number.  For example, OS001_0014482 is the 14482nd source of
Obs. ID 1.  The name convention of the ChaMPlane chandra source is
CXOPS Jhhmmss.s+-ddmmss, and the prefix of optical source names is ChOPS J.

Source coordinates 
Two sets of coordinates are given for each source; one is before aspect
correction and the other is after aspect correction. For example, in
the source position table of "browsing by ObsID" mode, "ra" and "dec"
columns are before aspect correction, and "ac_ra" and "ac_dec" columns
are after aspect correction. This is true for "gl", "gb", "srcname",
"ac_gl", "ac_gb", and "ac_srcname" columns. In "selecting sources by
coordinates" mode, the user defined coordinates are matched against
aspected corrected coordinates (ac_*).

Energy bands used in ChaMPlane 
   Name	 Range
   Bx	0.3 - 8.0 keV : wavdetect band (also used as B)
   Sx	0.3 - 2.5 keV : used only in XPIPE
   Hx	2.5 - 8.0 keV : used only in XPIPE
   Bc	0.5 - 8.0 keV 
   Sc	0.5 - 2.0 keV
   Hc	2.0 - 8.0 keV

Level
A "level" is assigned to each source for 
confirming validity of the source and making the analysis convenient. 

  Level ≥ 0: wavdetect
            everything detected by wavdetect
  Level ≥ 1: valid sources after V&V and source flag based cut
            flag ≠ 11x, 12x, 146
  Level ≥ 2: CCD selection
            sources in CCD 0, 1, 2, 3 for ACIS-I obs.
            sources in CCD 2, 3, 6, 7 for ACIS-S obs.
  Level ≥ 3: Off-axis limit
            sources within 400″ from the aimpoint for ACIS-I obs.
            sources in CCD 7 for ACIS-S obs.


Flag definition
 False sources by V&V
 	111 	False source by hot pixels or by bad bias values 
 	112 	False source by bad columns 
 	113 	False source due to readout streaks by a very strong source 
 	114 	False source by the FEP 0/3 problem
 	115 	Double source detected by the PSF effect
 	121 	Other spurious sources 
 Valid sources but source properties may be subject to a large uncertainty
 	141	Source region overlaps with neighbors' source regions 
 	142	No refinement on source region due to severe source region overlap 
 	143	Background region overlaps with neighbors' source regions
 	146	Source at the chip boundary 
 	147	Pile-up candidate (> 100 cts/ksec)	
 	148	Uncertain source position by flag = 115
 Other cases
 	151	Source is extended 
 	153	Target of the observation
 	154	Sources in the target region (e.g. point sources in a target cluster) 
 	157	The same source is found in other observations	
 	158	The same source is found in the stacked image


Flux estimation
For each source in a given energy band, multiple flux estimations are 
given from a few spectral and extinction models.
   extinction models
	nh1 : Drimmel et al. 2003, ApJ, 409, 205.
		assume  NH/E(B-V) = 5.8×1021 cm-2/mag
	nh2 : Schlegel et al. 1998, ApJ, 500, 525
		assume  NH/A(V) = 1.79×1021 cm-2/mag
   spectral models
	sp1 : Powerlaw 1.7
	sp2 : Powerlaw 1.4

References
Survey   Overview: Grindlay J. et al., 2005, submitted to ApJ (astro-ph/?) 
X-ray    analysis: Hong, J. et al., 2005, submitted to ApJ (astro-ph/?) 
Optical  analysis: Zhao, P. et al., 2005, submitted to ApJ (astro-ph/?) 
Quantile analysis: Hong, J. et al., 2004, ApJ, 614, 508 (astro-ph/0406463)(software)