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)