Last modified: 09 Dec 2021

URL: https://cxc.cfa.harvard.edu/ciao/threads/csccli/

Simple Command Line Access to the Chandra Source Catalog

CIAO 4.17 Science Threads


Overview

Synopsis:

The Chandra Source Catalog (CSC) , version 2, contains properties for nearly 317,000 point like sources observed by Chandra during its first 14 years. This includes source positions, fluxes, count rates, hardness ratios (colors), extent, and measures of variability in multiple energy bands; all of which are reported for each individual observation as well as merged properties for overlapping datasets.

The primary interface to query the source catalog is CSCView a Java-based graphical user interface (GUI). There is also a web based command line interface (CLI) that is available for users who experience problems running the Java application.

The CIAO contributed scripts search_csc and obsid_search_csc provide simple wrappers around the CLI interface for the two most common and simple searches: a radius search around a position and a search by a Chandra OBS_ID

They also provide access to the catalog data products and can optionally query the CSC Limiting Sensitivity service for upper limits when a source is not detected. This service is currently only available for Release 1 of the Chandra Source Catalog.

Purpose:

To show how to perform a simple search of the CSC catalog using either a Chandra OBS_ID or a position with radius.

Users who require more filtering and sorting capabilities should use the CSCView application.

Related Links:

  • For details on the Chandra Source Catalog, the properties, and data products, users should visit the Chandra Source Catalog web site.

Last Update: 09 Dec 2021 - Review for CIAO 4.14. Removed prism for CIAO 4.14.


Contents


Getting Started

To get started will assume that a user knows the position or name of a source of interest. As an example we will use the source

SDSS J1004+4112

from the Sload Digitial Sky Survey catalog.


Search by Position

We begin our search by simply using the search_csc script and providing the name of the object and a search radius (in the default units of arc-minutes). Since the name has a space it needs to be quoted.

unix% search_csc "SDSS J1004+4112" radius=1 outfile=none cat=csc2
search_csc
             pos = SDSS J1004+4112
          radius = 1
         outfile = none
         radunit = arcmin
         columns = INDEF
     sensitivity = no
        download = none
            root = ./
           bands = broad,wide
       filetypes = regevt,pha,arf,rmf,lc,psf,regexp
         catalog = csc2
         verbose = 1
         clobber = no
            mode = ql


89 rows returned by query
10 Different Master Source(s).
9 Different Observation(s).

name                	ra          	dec         	sepn	obsid	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	 5794	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	11546	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	11547	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	11548	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	11549	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	14495	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	14496	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	14498	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	14497	
 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	0.25'	 5794	
 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	0.25'	11546	
 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	0.25'	11547	
 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	0.25'	11548	
 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	0.25'	11549	
 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	0.25'	14495	
 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	0.25'	14496	
 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	0.25'	14498	
 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	0.25'	14497	
 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	0.19'	 5794	
 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	0.19'	11546	
 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	0.19'	11547	
 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	0.19'	11548	
 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	0.19'	11549	
 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	0.19'	14495	
 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	0.19'	14496	
 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	0.19'	14498	
 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	0.19'	14497	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	0.14'	 5794	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	0.14'	11546	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	0.14'	11547	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	0.14'	11548	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	0.14'	11549	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	0.14'	14495	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	0.14'	14496	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	0.14'	14498	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	0.14'	14497	
 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	0.4'	 5794	
 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	0.4'	11546	
 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	0.4'	11547	
 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	0.4'	11548	
 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	0.4'	11549	
 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	0.4'	14495	
 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	0.4'	14496	
 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	0.4'	14498	
 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	0.4'	14497	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	0.14'	11546	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	0.14'	11547	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	0.14'	11548	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	0.14'	11549	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	0.14'	14495	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	0.14'	14496	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	0.14'	14498	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	0.14'	14497	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	0.063'	 5794	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	0.063'	11546	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	0.063'	11547	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	0.063'	11548	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	0.063'	11549	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	0.063'	14495	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	0.063'	14496	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	0.063'	14498	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	0.063'	14497	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.00051'	 5794	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.00051'	11546	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.00051'	11547	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.00051'	11548	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.00051'	11549	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.00051'	14495	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.00051'	14496	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.00051'	14498	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.00051'	14497	
 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	0.46'	 5794	
 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	0.46'	11546	
 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	0.46'	11547	
 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	0.46'	11548	
 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	0.46'	11549	
 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	0.46'	14495	
 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	0.46'	14496	
 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	0.46'	14498	
 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	0.46'	14497	
 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	0.72'	 5794	
 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	0.72'	11546	
 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	0.72'	11547	
 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	0.72'	11548	
 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	0.72'	11549	
 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	0.72'	14495	
 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	0.72'	14496	
 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	0.72'	14498	
 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	0.72'	14497	

The results are printed to the screen. There are 10 sources in the CSC within 1 arcmin of the location SDSS J1004+4112. The script uses the NED name resolver to translate the name into a position. Setting the verbose level to 2 or higher displays the position.

unix% search_csc "SDSS J1004+4112" radius=1 outfile=none verbose=2 cat=csc2
...

Resolved SDSS J1004+4112 to ra=151.14557 dec=41.21185

The separation between the detected sources and the input coordinates are provided in the sepn (separation) column in the same units at the radius (default is arcmin).

Additional source properties can be requested by adding them to the columns parameter.

unix% search_csc "SDSS J1004+4112" radius=1 outfile= \
  columns=m.significance,m.flux_aper_b,o.theta,o.cnts_aper_b cat=csc2
...
name                	ra          	dec         	sepn	obsid	significance	flux_aper_b	theta	cnts_aper_b	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	 5794	     4.78	3.771e-15	    0.841	         31	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	11546	     4.78	3.771e-15	    0.639	          2	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	11547	     4.78	3.771e-15	    0.682	          4	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	11548	     4.78	3.771e-15	    0.219	          4	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	11549	     4.78	3.771e-15	    0.395	          1	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	14495	     4.78	3.771e-15	    0.435	          9	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	14496	     4.78	3.771e-15	    0.563	          7	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	14498	     4.78	3.771e-15	    0.245	          7	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	0.47'	14497	     4.78	3.771e-15	    0.206	          5	
...
 

Here we ask, for example, for the source significance [m.significance], the broad band (0.5-7.0 keV) flux [m.flux_aper_b], the location of the source relative to the optical axis [o.theta], and the number of broad band counts [o.cnts_aper_b]. The list of columns is quite extensive and includes all the columns discussed in the CSC pages. The o denotes an "observation" source property, computed from a single OBS_ID and m denotes a "master" source property which is computed from data from all the OBS_IDs a source was detected.

We can change the units of the search radius and it will change the units of the sepn values

unix% search_csc "SDSS J1004+4112" radius=10 radunit=arcsec out= cat=csc2
search_csc
             pos = SDSS J1004+4112
          radius = 10
         outfile = 
         radunit = arcsec
         columns = INDEF
     sensitivity = no
        download = none
            root = ./
           bands = broad,wide
       filetypes = regevt,pha,arf,rmf,lc,psf,regexp
         catalog = csc2
         verbose = 1
         clobber = no
            mode = ql


35 rows returned by query
4 Different Master Source(s).
9 Different Observation(s).

name                	ra          	dec         	sepn	obsid	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	8.4"	 5794	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	8.4"	11546	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	8.4"	11547	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	8.4"	11548	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	8.4"	11549	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	8.4"	14495	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	8.4"	14496	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	8.4"	14498	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	8.4"	14497	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	8.1"	11546	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	8.1"	11547	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	8.1"	11548	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	8.1"	11549	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	8.1"	14495	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	8.1"	14496	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	8.1"	14498	
2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	8.1"	14497	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	3.8"	 5794	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	3.8"	11546	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	3.8"	11547	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	3.8"	11548	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	3.8"	11549	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	3.8"	14495	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	3.8"	14496	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	3.8"	14498	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	3.8"	14497	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.031"	 5794	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.031"	11546	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.031"	11547	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.031"	11548	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.031"	11549	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.031"	14495	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.031"	14496	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.031"	14498	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	0.031"	14497	

When the output file is "none" or left blank, the source properties are only printed to the screen (with verbose >0). We can set the output file and it will save the Tab Separated Value (TSV) format results.

unix% search_csc "SDSS J1004+4112" radius=1 outfile=sdss_j1004+4112.tsv  \
  columns=m.significance,m.flux_aper_b,o.theta,o.cnts_aper_b verbose=0 cat=csc2

unix% cat sdss_j1004+4112.tsv
#Column	sepn	(E9.6)		(.sepn)	[""]	[]
#Column	name	(A22)	Source name in the format '2CXO Jhhmmss.s{+|-}ddmmss[X]'	(master_source.name)	[""]	[]
#Column	ra	(E9.6)	Source position, ICRS right ascension	(master_source.ra)	["deg"]	[pos.eq.ra;meta.main]
#Column	dec	(E9.6)	Source position, ICRS declination	(master_source.dec)	["deg"]	[pos.eq.dec;meta.main]
#Column	instrument	(A4)	Instrument used for the observation; 'ACIS' or 'HRC'	(observation_source.instrument)	[""]	[]
#Column	obsid	(I5)	Observation identifier	(observation_source.obsid)	[""]	[]
#Column	obi	(I3)	Observation interval number	(observation_source.obi)	[""]	[]
#Column	region_id	(I4)	Detection region identifier (component number)	(observation_source.region_id)	[""]	[]
#Column	match_type	(A11)	Type of match	(master_stack_assoc.match_type)	[""]	[meta.code]
#Column	detect_stack_id	(A24)	Detect stack identifier (designation of observation stack used for source detection) in the format '{acis|hrc}fJhhmmsss{+|-}ddmmss_nnn'	(stack_source.detect_stack_id)	[""]	[]
#Column	significance	(F9.2)	Highest flux significance (S/N) across all stacked observations and energy bands	(master_source.significance)	[""]	[]
#Column	flux_aper_b	(E9.3)	Aperture-corrected net energy flux inferred from the source region aperture, best estimate derived from the longest block of a multi-band, flux-ordered Bayesian Block analysis of the contributing observations, and calculated by counting X-ray events; ACIS broad (0.5-7.0 keV) energy band	(master_source.flux_aper_b)	["erg/s/cm^2"]	[]
#Column	theta	(F9.3)	PSF 90% ECF aperture off-axis angle	(observation_source.theta)	["arcmin"]	[]
#Column	cnts_aper_b	(I11)	Total counts observed in the modified source region aperture; ACIS broad (0.5-7.0 keV) energy band	(observation_source.cnts_aper_b)	["count"]	[]
sepn	name	ra	dec	instrument	obsid	obi	region_id	match_type	detect_stack_id	significance	flux_aper_b	theta	cnts_aper_b
2.819357e+01	 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	ACIS	 5794	  0	  26	          u	acisfJ1004335p411357_001	     4.78	3.771e-15	    0.841	         31
2.819357e+01	 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	ACIS	11546	  0	  37	          u	acisfJ1004338p411243_001	     4.78	3.771e-15	    0.639	          2
2.819357e+01	 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	ACIS	11547	  0	  37	          u	acisfJ1004338p411243_001	     4.78	3.771e-15	    0.682	          4
2.819357e+01	 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	ACIS	11548	  0	  37	          u	acisfJ1004338p411243_001	     4.78	3.771e-15	    0.219	          4
2.819357e+01	 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	ACIS	11549	  0	  37	          u	acisfJ1004338p411243_001	     4.78	3.771e-15	    0.395	          1
2.819357e+01	 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	ACIS	14495	  0	  37	          u	acisfJ1004338p411243_001	     4.78	3.771e-15	    0.435	          9
2.819357e+01	 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	ACIS	14496	  0	  37	          u	acisfJ1004338p411243_001	     4.78	3.771e-15	    0.563	          7
2.819357e+01	 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	ACIS	14498	  0	  37	          u	acisfJ1004338p411243_001	     4.78	3.771e-15	    0.245	          7
2.819357e+01	 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	ACIS	14497	  1	  37	          u	acisfJ1004338p411243_001	     4.78	3.771e-15	    0.206	          5
1.474465e+01	 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	ACIS	 5794	  0	  19	          u	acisfJ1004335p411357_001	    37.23	1.016e-13	    1.382	       1275
1.474465e+01	 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	ACIS	11546	  0	  31	          u	acisfJ1004338p411243_001	    37.23	1.016e-13	    0.123	         66
1.474465e+01	 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	ACIS	11547	  0	  31	          u	acisfJ1004338p411243_001	    37.23	1.016e-13	    0.239	         93
1.474465e+01	 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	ACIS	11548	  0	  31	          u	acisfJ1004338p411243_001	    37.23	1.016e-13	    0.454	         60
1.474465e+01	 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	ACIS	11549	  0	  31	          u	acisfJ1004338p411243_001	    37.23	1.016e-13	    0.303	        110
1.474465e+01	 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	ACIS	14495	  0	  31	          u	acisfJ1004338p411243_001	    37.23	1.016e-13	    0.158	        328
1.474465e+01	 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	ACIS	14496	  0	  31	          u	acisfJ1004338p411243_001	    37.23	1.016e-13	    0.033	        342
1.474465e+01	 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	ACIS	14498	  0	  31	          u	acisfJ1004338p411243_001	    37.23	1.016e-13	    0.299	        376
1.474465e+01	 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	ACIS	14497	  1	  31	          u	acisfJ1004338p411243_001	    37.23	1.016e-13	    0.340	        343
1.151900e+01	 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	ACIS	 5794	  0	  23	          u	acisfJ1004335p411357_001	    27.73	6.231e-14	    1.149	        722
1.151900e+01	 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	ACIS	11546	  0	  36	          u	acisfJ1004338p411243_001	    27.73	6.231e-14	    0.354	         79
1.151900e+01	 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	ACIS	11547	  0	  36	          u	acisfJ1004338p411243_001	    27.73	6.231e-14	    0.375	         61
1.151900e+01	 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	ACIS	11548	  0	  36	          u	acisfJ1004338p411243_001	    27.73	6.231e-14	    0.221	         48
1.151900e+01	 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	ACIS	11549	  0	  36	          u	acisfJ1004338p411243_001	    27.73	6.231e-14	    0.274	         83
1.151900e+01	 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	ACIS	14495	  0	  36	          u	acisfJ1004338p411243_001	    27.73	6.231e-14	    0.197	        193
1.151900e+01	 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	ACIS	14496	  0	  36	          u	acisfJ1004338p411243_001	    27.73	6.231e-14	    0.257	        164
1.151900e+01	 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	ACIS	14498	  0	  36	          u	acisfJ1004338p411243_001	    27.73	6.231e-14	    0.106	        228
1.151900e+01	 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	ACIS	14497	  1	  36	          u	acisfJ1004338p411243_001	    27.73	6.231e-14	    0.107	        143
8.367418e+00	 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	ACIS	 5794	  0	  22	          u	acisfJ1004335p411357_001	     5.18	3.521e-15	    1.240	         86
8.367418e+00	 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	ACIS	11546	  0	  34	          u	acisfJ1004338p411243_001	     5.18	3.521e-15	    0.285	          0
8.367418e+00	 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	ACIS	11547	  0	  34	          u	acisfJ1004338p411243_001	     5.18	3.521e-15	    0.290	          0
8.367418e+00	 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	ACIS	11548	  0	  34	          u	acisfJ1004338p411243_001	     5.18	3.521e-15	    0.290	          6
8.367418e+00	 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	ACIS	11549	  0	  34	          u	acisfJ1004338p411243_001	     5.18	3.521e-15	    0.298	          4
8.367418e+00	 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	ACIS	14495	  0	  34	          u	acisfJ1004338p411243_001	     5.18	3.521e-15	    0.179	         12
8.367418e+00	 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	ACIS	14496	  0	  34	          u	acisfJ1004338p411243_001	     5.18	3.521e-15	    0.175	         17
8.367418e+00	 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	ACIS	14498	  0	  34	          u	acisfJ1004338p411243_001	     5.18	3.521e-15	    0.182	          6
8.367418e+00	 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	ACIS	14497	  1	  34	          u	acisfJ1004338p411243_001	     5.18	3.521e-15	    0.194	         20
2.376900e+01	 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	ACIS	 5794	  0	  17	          u	acisfJ1004335p411357_001	    31.20	1.096e-13	    1.629	        888
2.376900e+01	 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	ACIS	11546	  0	  28	          u	acisfJ1004338p411243_001	    31.20	1.096e-13	    0.216	         59
2.376900e+01	 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	ACIS	11547	  0	  28	          u	acisfJ1004338p411243_001	    31.20	1.096e-13	    0.200	         53
2.376900e+01	 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	ACIS	11548	  0	  28	          u	acisfJ1004338p411243_001	    31.20	1.096e-13	    0.673	         73
2.376900e+01	 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	ACIS	11549	  0	  28	          u	acisfJ1004338p411243_001	    31.20	1.096e-13	    0.541	         64
2.376900e+01	 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	ACIS	14495	  0	  28	          u	acisfJ1004338p411243_001	    31.20	1.096e-13	    0.405	        204
2.376900e+01	 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	ACIS	14496	  0	  28	          u	acisfJ1004338p411243_001	    31.20	1.096e-13	    0.230	        212
2.376900e+01	 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	ACIS	14498	  0	  28	          u	acisfJ1004338p411243_001	    31.20	1.096e-13	    0.554	        266
2.376900e+01	 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	ACIS	14497	  1	  28	          u	acisfJ1004338p411243_001	    31.20	1.096e-13	    0.586	        241
8.124405e+00	2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	ACIS	11546	  0	9001	          u	acisfJ1004338p411243_001	    30.08	      NaN	    0.274	        155
8.124405e+00	2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	ACIS	11547	  0	9001	          u	acisfJ1004338p411243_001	    30.08	      NaN	    0.273	        191
8.124405e+00	2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	ACIS	11548	  0	9001	          u	acisfJ1004338p411243_001	    30.08	      NaN	    0.304	        155
8.124405e+00	2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	ACIS	11549	  0	9001	          u	acisfJ1004338p411243_001	    30.08	      NaN	    0.307	        154
8.124405e+00	2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	ACIS	14495	  0	9001	          u	acisfJ1004338p411243_001	    30.08	      NaN	    0.182	        591
8.124405e+00	2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	ACIS	14496	  0	9001	          u	acisfJ1004338p411243_001	    30.08	      NaN	    0.161	        588
8.124405e+00	2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	ACIS	14498	  0	9001	          u	acisfJ1004338p411243_001	    30.08	      NaN	    0.199	        551
8.124405e+00	2CXO J100434.2+411242X	1.511426e+02	4.121192e+01	ACIS	14497	  1	9001	          u	acisfJ1004338p411243_001	    30.08	      NaN	    0.212	        550
3.773882e+00	 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	ACIS	 5794	  0	  20	          u	acisfJ1004335p411357_001	    29.67	1.029e-13	    1.329	       1184
3.773882e+00	 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	ACIS	11546	  0	  32	          u	acisfJ1004338p411243_001	    29.67	1.029e-13	    0.311	         63
3.773882e+00	 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	ACIS	11547	  0	  32	          u	acisfJ1004338p411243_001	    29.67	1.029e-13	    0.173	         43
3.773882e+00	 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	ACIS	11548	  0	  32	          u	acisfJ1004338p411243_001	    29.67	1.029e-13	    0.352	         47
3.773882e+00	 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	ACIS	11549	  0	  32	          u	acisfJ1004338p411243_001	    29.67	1.029e-13	    0.431	         30
3.773882e+00	 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	ACIS	14495	  0	  32	          u	acisfJ1004338p411243_001	    29.67	1.029e-13	    0.296	        206
3.773882e+00	 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	ACIS	14496	  0	  32	          u	acisfJ1004338p411243_001	    29.67	1.029e-13	    0.183	        211
3.773882e+00	 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	ACIS	14498	  0	  32	          u	acisfJ1004338p411243_001	    29.67	1.029e-13	    0.318	        190
3.773882e+00	 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	ACIS	14497	  1	  32	          u	acisfJ1004338p411243_001	    29.67	1.029e-13	    0.313	        224
3.073585e-02	 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	ACIS	 5794	  0	  21	          u	acisfJ1004335p411357_001	    38.10	1.241e-13	    1.275	       1521
3.073585e-02	 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	ACIS	11546	  0	  33	          u	acisfJ1004338p411243_001	    38.10	1.241e-13	    0.363	         87
3.073585e-02	 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	ACIS	11547	  0	  33	          u	acisfJ1004338p411243_001	    38.10	1.241e-13	    0.229	         43
3.073585e-02	 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	ACIS	11548	  0	  33	          u	acisfJ1004338p411243_001	    38.10	1.241e-13	    0.297	         65
3.073585e-02	 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	ACIS	11549	  0	  33	          u	acisfJ1004338p411243_001	    38.10	1.241e-13	    0.439	         43
3.073585e-02	 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	ACIS	14495	  0	  33	          u	acisfJ1004338p411243_001	    38.10	1.241e-13	    0.316	        437
3.073585e-02	 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	ACIS	14496	  0	  33	          u	acisfJ1004338p411243_001	    38.10	1.241e-13	    0.235	        444
3.073585e-02	 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	ACIS	14498	  0	  33	          u	acisfJ1004338p411243_001	    38.10	1.241e-13	    0.298	        377
3.073585e-02	 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	ACIS	14497	  1	  33	          u	acisfJ1004338p411243_001	    38.10	1.241e-13	    0.280	        362
2.745783e+01	 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	ACIS	 5794	  0	  18	          u	acisfJ1004335p411357_001	    11.20	1.236e-14	    1.584	        165
2.745783e+01	 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	ACIS	11546	  0	  30	          u	acisfJ1004338p411243_001	    11.20	1.236e-14	    0.705	         14
2.745783e+01	 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	ACIS	11547	  0	  30	          u	acisfJ1004338p411243_001	    11.20	1.236e-14	    0.412	         17
2.745783e+01	 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	ACIS	11548	  0	  30	          u	acisfJ1004338p411243_001	    11.20	1.236e-14	    0.666	         12
2.745783e+01	 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	ACIS	11549	  0	  30	          u	acisfJ1004338p411243_001	    11.20	1.236e-14	    0.891	         19
2.745783e+01	 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	ACIS	14495	  0	  30	          u	acisfJ1004338p411243_001	    11.20	1.236e-14	    0.755	         14
2.745783e+01	 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	ACIS	14496	  0	  30	          u	acisfJ1004338p411243_001	    11.20	1.236e-14	    0.602	         18
2.745783e+01	 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	ACIS	14498	  0	  30	          u	acisfJ1004338p411243_001	    11.20	1.236e-14	    0.754	         21
2.745783e+01	 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	ACIS	14497	  1	  30	          u	acisfJ1004338p411243_001	    11.20	1.236e-14	    0.722	         16
4.343332e+01	 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	ACIS	 5794	  0	  24	          u	acisfJ1004335p411357_001	     2.49	1.406e-15	    1.497	         10
4.343332e+01	 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	ACIS	11546	  0	 221	          n	acisfJ1004338p411243_001	     2.49	1.406e-15	    1.055	          0
4.343332e+01	 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	ACIS	11547	  0	 221	          n	acisfJ1004338p411243_001	     2.49	1.406e-15	    0.783	          0
4.343332e+01	 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	ACIS	11548	  0	 221	          n	acisfJ1004338p411243_001	     2.49	1.406e-15	    0.781	          1
4.343332e+01	 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	ACIS	11549	  0	 221	          n	acisfJ1004338p411243_001	     2.49	1.406e-15	    1.149	          1
4.343332e+01	 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	ACIS	14495	  0	 221	          n	acisfJ1004338p411243_001	     2.49	1.406e-15	    1.039	          0
4.343332e+01	 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	ACIS	14496	  0	 221	          n	acisfJ1004338p411243_001	     2.49	1.406e-15	    0.934	          3
4.343332e+01	 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	ACIS	14498	  0	 221	          n	acisfJ1004338p411243_001	     2.49	1.406e-15	    0.965	          0
4.343332e+01	 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	ACIS	14497	  1	 221	          n	acisfJ1004338p411243_001	     2.49	1.406e-15	    0.907	          1

Users will notice that some additional columns are also included: obi, region_id, match_type, and instrument. These columns are required by the script and are always included in the results. Also users should be aware that - contrary to what happens when the results are just printed to the screen - the sepn value is always saved in units of arcsec regardless of the radunit value.

When the default columns=INDEF is set, many of the most common columns are retrieved and saved to the output file; however, only a few are printed to the screen.


Search by OBS_ID

After reviewing the above results, we notice that most of the sources belong to the same Chandra obsid: 5794. Let us now widen our search and see which other sources were also detected in this observation. To do this we switch to use the obsid_search_csc tool

unix% obsid_search_csc 5794 out="" cat=csc2\
  column=o.theta,o.cnts_aper_b,o.ks_prob_b,o.flux_significance_b

obsid_search_csc
           obsid = 5794
         outfile = 
         columns = o.theta,o.cnts_aper_b,o.ks_prob_b,o.flux_significance_b
        download = none
            root = ./
           bands = broad,wide
       filetypes = regevt,pha,arf,rmf,lc,psf,regexp
         catalog = csc2
         verbose = 1
         clobber = no
            mode = ql


58 rows returned by query
58 Different Master Source(s).
1 Different Observation(s).

name                	ra          	dec         	obsid	theta	cnts_aper_b	ks_prob_b	flux_significance_b	
 2CXO J100414.3+411259	1.510597e+02	4.121642e+01	 5794	    3.737	         93	    0.808	     8.30	
 2CXO J100415.2+411155	1.510634e+02	4.119875e+01	 5794	    3.995	        152	    0.959	    10.55	
 2CXO J100416.6+410813	1.510695e+02	4.113695e+01	 5794	    6.563	         48	    0.988	     4.78	
 2CXO J100416.7+411204	1.510700e+02	4.120118e+01	 5794	    3.665	         21	    0.216	     3.35	
 2CXO J100419.0+411029	1.510792e+02	4.117492e+01	 5794	    4.408	         47	    0.269	     5.33	
 2CXO J100419.4+411024	1.510811e+02	4.117344e+01	 5794	    4.428	         70	    0.895	     6.95	
 2CXO J100419.4+411355	1.510810e+02	4.123209e+01	 5794	    2.643	          4	      NaN	     0.00	
 2CXO J100419.9+411154	1.510829e+02	4.119836e+01	 5794	    3.279	         18	    0.532	     3.35	
 2CXO J100420.3+411414	1.510847e+02	4.123735e+01	 5794	    2.495	        100	    0.466	     8.87	
 2CXO J100421.3+411054	1.510888e+02	4.118180e+01	 5794	    3.816	          5	      NaN	     0.00	
 2CXO J100423.9+411428	1.510997e+02	4.124119e+01	 5794	    1.872	         14	    0.800	     2.94	
 2CXO J100424.1+410828	1.511005e+02	4.114139e+01	 5794	    5.753	         13	      NaN	     0.00	
 2CXO J100425.2+411158	1.511054e+02	4.119969e+01	 5794	    2.506	         49	    0.381	     5.98	
 2CXO J100427.5+411057	1.511146e+02	4.118252e+01	 5794	    3.213	          9	      NaN	     2.16	
 2CXO J100427.5+411232	1.511149e+02	4.120905e+01	 5794	    1.803	          4	      NaN	     0.00	
 2CXO J100428.3+411128	1.511183e+02	4.119131e+01	 5794	    2.657	         20	    0.489	     3.59	
 2CXO J100428.5+411229	1.511189e+02	4.120824e+01	 5794	    1.738	          3	      NaN	     0.00	
 2CXO J100429.2+411354	1.511217e+02	4.123187e+01	 5794	    0.807	          9	    0.296	     2.61	
 2CXO J100430.1+410944	1.511258e+02	4.116224e+01	 5794	    4.269	         72	    0.735	     7.22	
 2CXO J100430.3+411414	1.511266e+02	4.123737e+01	 5794	    0.649	         18	    0.015	     3.53	
 2CXO J100430.5+411056	1.511275e+02	4.118250e+01	 5794	    3.059	          3	      NaN	     0.00	
 2CXO J100430.6+411322	1.511276e+02	4.122298e+01	 5794	    0.787	          7	    0.763	     2.26	
 2CXO J100430.6+411405	1.511275e+02	4.123491e+01	 5794	    0.560	         29	    0.449	     4.70	
 2CXO J100431.6+410936	1.511319e+02	4.116013e+01	 5794	    4.363	        456	    0.624	    18.35	
 2CXO J100433.4+411019	1.511394e+02	4.117216e+01	 5794	    3.630	         15	    0.986	     2.79	
 2CXO J100433.6+411307	1.511404e+02	4.121864e+01	 5794	    0.841	         31	    1.000	     4.78	
 2CXO J100433.8+411018	1.511411e+02	4.117177e+01	 5794	    3.652	         97	    0.410	     8.39	
 2CXO J100433.8+411234	1.511410e+02	4.120961e+01	 5794	    1.382	       1275	    0.303	    30.92	
 2CXO J100434.0+411248	1.511420e+02	4.121356e+01	 5794	    1.149	        722	    0.373	    23.05	
 2CXO J100434.1+410840	1.511424e+02	4.114457e+01	 5794	    5.301	         28	    0.167	     2.32	
 2CXO J100434.1+411243	1.511425e+02	4.121211e+01	 5794	    1.240	         86	    0.782	     5.18	
 2CXO J100434.2+411220	1.511429e+02	4.120557e+01	 5794	    1.629	        888	    0.232	    25.85	
 2CXO J100434.8+411239	1.511451e+02	4.121087e+01	 5794	    1.329	       1184	    0.047	    29.67	
 2CXO J100434.9+411242	1.511456e+02	4.121186e+01	 5794	    1.275	       1521	    0.625	    33.72	
 2CXO J100436.3+410946	1.511514e+02	4.116301e+01	 5794	    4.212	         38	    0.724	     4.72	
 2CXO J100437.0+411109	1.511544e+02	4.118588e+01	 5794	    2.877	         17	    0.073	     3.14	
 2CXO J100437.0+411532	1.511543e+02	4.125896e+01	 5794	    1.713	         19	    0.304	     3.53	
 2CXO J100437.1+411231	1.511549e+02	4.120887e+01	 5794	    1.584	        165	    0.846	    11.20	
 2CXO J100437.2+410838	1.511554e+02	4.114396e+01	 5794	    5.370	         15	      NaN	     0.00	
 2CXO J100437.2+410936	1.511553e+02	4.116015e+01	 5794	    4.408	          8	      NaN	     0.00	
 2CXO J100437.2+411445	1.511552e+02	4.124585e+01	 5794	    1.061	        162	    0.499	    11.20	
 2CXO J100438.1+411004	1.511591e+02	4.116789e+01	 5794	    3.985	         11	      NaN	     0.00	
 2CXO J100438.3+411124	1.511598e+02	4.119010e+01	 5794	    2.711	          3	      NaN	     0.00	
 2CXO J100438.7+411249	1.511614e+02	4.121385e+01	 5794	    1.497	         10	    0.873	     2.49	
 2CXO J100438.8+411507	1.511618e+02	4.125195e+01	 5794	    1.531	          6	    0.822	     2.06	
 2CXO J100439.5+411446	1.511649e+02	4.124622e+01	 5794	    1.403	          7	    0.029	     2.16	
 2CXO J100441.0+410943	1.511709e+02	4.116218e+01	 5794	    4.457	        500	    0.305	    19.82	
 2CXO J100441.3+411110	1.511723e+02	4.118616e+01	 5794	    3.157	         20	    0.467	     3.70	
 2CXO J100442.0+411059	1.511753e+02	4.118321e+01	 5794	    3.373	         79	    0.623	     7.55	
 2CXO J100442.8+411400	1.511785e+02	4.123357e+01	 5794	    1.759	          0	      NaN	     0.00	
 2CXO J100443.0+411342	1.511796e+02	4.122847e+01	 5794	    1.821	          9	    0.841	     2.61	
 2CXO J100444.9+411348	1.511873e+02	4.123015e+01	 5794	    2.159	         98	    0.800	     8.85	
 2CXO J100445.8+411246	1.511911e+02	4.121297e+01	 5794	    2.607	          9	    0.507	     2.32	
 2CXO J100446.0+411215	1.511918e+02	4.120429e+01	 5794	    2.909	         28	    0.597	     4.49	
 2CXO J100446.4+411447	1.511934e+02	4.124666e+01	 5794	    2.572	        113	    0.673	     9.39	
 2CXO J100451.7+410831	1.512157e+02	4.114204e+01	 5794	    6.426	        123	    0.918	     7.45	
 2CXO J100451.9+410911	1.512165e+02	4.115311e+01	 5794	    5.898	         43	    0.155	     2.50	
 2CXO J100454.7+411231	1.512282e+02	4.120870e+01	 5794	    4.250	          6	      NaN	     0.00	

We see that there were a total of 58 sources covered by this observation. In CSC2: sources are detected on combined datasets; but source properties are computed for all sources in each individual obsid. The columns parameter accepts the same inputs as the search_csc script and the screen and file outputs behave the same. The only difference is that there is no sepn column returned: since we are searching by observation there is no distance to compute.

Other Observations?

One might wonder if the original position was observed multiple times? We can try the find_chandra_obsid tool

unix% find_chandra_obsid "SDSS J1004+4112"
# obsid  sepn   inst grat   time    obsdate   piname            target
5794      0.2 ACIS-S NONE   80.1 2005-01-01    Inada "SDSS J1004+4112"
11546     0.1 ACIS-S NONE    6.0 2010-03-08 Kochanek     SDSS1004+4112
11547     0.1 ACIS-S NONE    6.0 2010-06-19 Kochanek     SDSS1004+4112
11548     0.1 ACIS-S NONE    6.0 2010-09-23 Kochanek     SDSS1004+4112
11549     0.1 ACIS-S NONE    6.0 2011-01-30 Kochanek     SDSS1004+4112
14495     0.1 ACIS-S NONE   24.7 2013-01-27 Kochanek     SDSS1004+4112
14496     0.1 ACIS-S NONE   24.7 2013-03-01 Kochanek     SDSS1004+4112
14497     0.1 ACIS-S NONE   24.1 2013-10-05 Kochanek     SDSS1004+4112
14498     0.1 ACIS-S NONE   23.8 2013-11-16 Kochanek     SDSS1004+4112
14499     0.1 ACIS-S NONE   23.3 2014-04-29 Kochanek     SDSS1004+4112
14500     0.1 ACIS-S NONE   24.7 2014-06-02 Kochanek     SDSS1004+4112
19632     0.1 ACIS-S NONE   40.1 2017-01-23  Chartas     SDSS1004+4112
19633     0.1 ACIS-S NONE   39.5 2017-04-16  Chartas     SDSS1004+4112
19634     0.1 ACIS-S NONE   35.9 2017-06-27  Chartas     SDSS1004+4112
19635     0.1 ACIS-S NONE   38.4 2017-10-01  Chartas     SDSS1004+4112
19636     0.1 ACIS-S NONE   36.0 2018-01-17  Chartas     SDSS1004+4112
19637     0.1 ACIS-S NONE   39.5 2018-04-19  Chartas     SDSS1004+4112

We can see that there are 17 other observations that imaged our source. Why where not all of these our original search results? Without doing much analysis, the easiest thing to notice is that the dates of the observations are in 2017 and 2018. Version 2 of the catalog only includes data through 2014.


Retrieve Data Products

[NOTE]
Slow downloads

The CXC is aware that file downloads using the command line interface (used by these scripts) is running very slowly. We are working to improve the performance.

The data products used to create the source properties are also available for each source. This includes both observation level products, like full field event files, exposure maps, and background images, as well as per source products such as PSFs, ARF, RMF, spectra, and light-curves.

Both search_csc and obsid_search_csc have a download parameter. If set to none (default) no data products are retrieved. If set to ask or all then data products for each source and each observation will be downloaded as specified in the bands and filetypes parameters. To retrieve all the default data products for a small search would look something like this:

unix% search_csc "SDSS J1004+4112" radius=1 radunit=arcsec outfile= download=ask verbose=0 cat=csc2
Download data for  2CXO J100434.9+411242 in 05794_000 [y,n,a,q]: y
Download data for  2CXO J100434.9+411242 in 11546_000 [y,n,a,q]: y
Download data for  2CXO J100434.9+411242 in 11547_000 [y,n,a,q]: q
Skipping remaining sources

unix% /bin/ls -F 2CXOJ100434.9+411242/
05794_000/
11546_000/

unix% find 2CXOJ100434.9+411242 -type f | sort
2CXOJ100434.9+411242/05794_000/acisf05794_000N020_evt3.fits.gz
2CXOJ100434.9+411242/05794_000/acisf05794_000N021_r0021_regevt3.fits.gz
2CXOJ100434.9+411242/05794_000/acisf05794_000N022_r0021_arf3.fits.gz
2CXOJ100434.9+411242/05794_000/acisf05794_000N022_r0021_rmf3.fits.gz
2CXOJ100434.9+411242/05794_000/acisf05794_000N022_r0021b_lc3.fits.gz
2CXOJ100434.9+411242/05794_000/acisf05794_000N022_r0021b_regexp3.fits.gz
2CXOJ100434.9+411242/05794_000/acisf05794_000N023_r0021_pha3.fits.gz
2CXOJ100434.9+411242/05794_000/acisf05794_000N025_r0021b_psf3.fits.gz
2CXOJ100434.9+411242/11546_000/acisf11546_000N020_evt3.fits.gz
2CXOJ100434.9+411242/11546_000/acisf11546_000N020_r0033_regevt3.fits.gz
2CXOJ100434.9+411242/11546_000/acisf11546_000N021_r0033_arf3.fits.gz
2CXOJ100434.9+411242/11546_000/acisf11546_000N021_r0033_rmf3.fits.gz
2CXOJ100434.9+411242/11546_000/acisf11546_000N021_r0033b_lc3.fits.gz
2CXOJ100434.9+411242/11546_000/acisf11546_000N021_r0033b_regexp3.fits.gz
2CXOJ100434.9+411242/11546_000/acisf11546_000N022_r0033_pha3.fits.gz
2CXOJ100434.9+411242/11546_000/acisf11546_000N025_r0033b_psf3.fits.gz
2CXOJ100434.9+411242/11547_000/acisf11547_000N020_evt3.fits.gz
2CXOJ100434.9+411242/11547_000/acisf11547_000N021_r0033b_lc3.fits.gz

The search_csc script organizes the files into directories based on the source name, then OBS_ID or detect stack ID. All the files are returned gzip'ed.

If we use the obsid_search_csc script the same data products can be retrieved, but they are stored in a slightly different directory structure

unix% obsid_search_csc 5794 download=ask outfile="" col=INDEF filetypes=evt,pha,arf,rmf verb=0
Download data for  2CXO J100414.3+411259 in 05794_000 [y,n,a,q]: y
Download data for  2CXO J100415.2+411155 in 05794_000 [y,n,a,q]: y
Download data for  2CXO J100416.6+410813 in 05794_000 [y,n,a,q]: q
Skipping remaining sources

unix% /bin/ls -F 5794/
acisf05794_000N020_evt3.fits.gz
r0013/
r0025/

unix % find 5794 -type f | sort
5794/acisf05794_000N020_evt3.fits.gz
5794/r0013/acisf05794_000N022_r0013_arf3.fits.gz
5794/r0013/acisf05794_000N022_r0013_rmf3.fits.gz
5794/r0013/acisf05794_000N023_r0013_pha3.fits.gz
5794/r0025/acisf05794_000N021_r0025_arf3.fits.gz
5794/r0025/acisf05794_000N021_r0025_rmf3.fits.gz
5794/r0025/acisf05794_000N022_r0025_pha3.fits.gz

Now the directory structure starts with the OBS_ID and with a sub directory for each source. Since the evt file is common to all the sources, it is stored in the OBS_ID directory. Note: by entering 'q' when prompted we quit out of downloading any more data products, so only the files for the first two sources were retrieved.


Using results with CIAO

DM ASCII Kernel

To use the output with CIAO tools you must explicitly specify that the file is in TSV format using the [opt kernel=text/tsv] directive as part of the virtual file syntax.

unix% obsid_search_csc 5794 out=5794.tsv cat=csc2\
  column=o.theta,o.cnts_aper_b,o.ks_prob_b,o.flux_significance_b verb=0 clob+

unix% dmlist "5794.tsv[opt kernel=text/tsv]" cols
--------------------------------------------------------------------------------
Columns for Table Block 5794.tsv
--------------------------------------------------------------------------------
 
ColNo  Name                 Unit        Type             Range
   1   name                              String[22]                          Source name in the format '2CXO Jhhmmss.s{+|-}ddmmss[X]'
   2   ra                   deg          Real4          -Inf:+Inf            Source position, ICRS right ascension
   3   dec                  deg          Real4          -Inf:+Inf            Source position, ICRS declination
   4   instrument                        String[4]                           Instrument used for the observation; 'ACIS' or 'HRC'
   5   obsid                             Int4           -                    Observation identifier
   6   obi                               Int4           -                    Observation interval number
   7   region_id                         Int4           -                    Detection region identifier (component number)
   8   match_type                        String[11]                          Type of match
   9   detect_stack_id                   String[24]                          Detect stack identifier (designation of observation stack used for source detect
  10   theta                arcmin       Real4          -Inf:+Inf            PSF 90% ECF aperture off-axis angle
  11   cnts_aper_b          count        Int4           -                    Total counts observed in the modified source region aperture; ACIS broad (0.5-7.
  12   ks_prob_b                         Real4          -Inf:+Inf            Intra-observation Kolmogorov-Smirnov test variability probability (highest value
  13   flux_significance_b               Real4          -Inf:+Inf            Significance of the single-observation detection determined from the ratio of th

unix% dmstat "5794.tsv[opt kernel=text/tsv][cols ks_prob_b]" sig+ med+
ks_prob_b
    min:	0.014999999665 	      @:	20 
    max:	1 	      @:	26 
   mean:	0.54813333632 
 median:	0.53200000525 
  sigma:	0.28815139674 
    sum:	24.666000134 
   good:	45 
   null:	13 

unix% dmsort "5794.tsv[opt kernel=text/tsv]" sort_by_theta.fits theta cl+

See also ahelp dmascii


Using with SAOImage ds9

The TSV file can be loaded directly into SAOImage ds9. You can load it via the command line

unix% ds9 5794/acisf05794_000N001_evt3.fits.gz -catalog import tsv 5794.tsv

Or the file can be loaded from with the GUI itself. Once the event file is loaded you can goto: Analysis → Catalog Tool ... then in the catalog tool window goto File → Import → Tab-Separated-Value → 5794.tsv

ds9 catalog display

Users can then use the catalog tool to interact with the catalog table and source properties. The data can also be transmitted to other SAMP enabled applications such as TOPCAT.


Upper Limits

[NOTE]
CSC2 upper limits not currently accessible

Upper limits for catalog=csc2 are not currently accessible via these command line scripts. The examples below are for catalog=csc1.

If a source is not detected, but an observation covering that part of the sky is included in the catalog, then an upper limit on the source flux (in photon units) is also available.

unix% search_csc "10 04 34.2 +41 12 40" radius=1 radunit=arcsec outfile= cat=csc1
search_csc
             pos = 10 04 34.2 +41 12 40
          radius = 1
         outfile = 
         radunit = arcsec
         columns = INDEF
     sensitivity = no
        download = none
            root = ./
           bands = broad,wide
       filetypes = regevt,pha,arf,rmf,lc,psf,regexp
         catalog = csc1
         verbose = 1
         clobber = no
            mode = ql


0 rows returned by query
0 Different Master Source(s).
0 Different Observation(s).

unix% search_csc "10 04 34.2 +41 12 40" radius=1 radunit=arcsec outfile= sensitivity=yes cat=csc1
search_csc
             pos = 10 04 34.2 +41 12 40
          radius = 1
         outfile = 
         radunit = arcsec
         columns = INDEF
     sensitivity = yes
        download = none
            root = ./
           bands = broad,wide
       filetypes = regevt,pha,arf,rmf,lc,psf,regexp
         catalog = csc1
         verbose = 1
         clobber = no
            mode = ql

CSC Sensitivity for position: 151.1426,41.2112
  broad band : 3.3601e-7 [photons/cm^2/s]
  wide band : NaN [photons/cm^2/s]

0 rows returned by query
0 Different Master Source(s).
0 Different Observation(s).

In this example, a source at 10:04:34.2 +41:12:40, would need to have been brighter than 3.36 e-7 photon/cm^2/sec in the broad band to be included in the catalog. If there is no sensitivity in the catalog then a value of NaN is returned. This does not mean that the part of the sky was not observed by Chandra at all, just that, if it was observed, the data were not included in the catalog. To determine if a point was observed use the find_chandra_obsid tool


More options?

Users who need to construct more complicated queries (eg variable sources with some range of hardness ratios etc.) or who need to perform cross matches, must use the CSCView application or use the CSCCLI interface directly.

Research that makes use of the data in the catalog should site Evans et al 2010, ApJS 189, 37.


History

25 Jul 2013 Initial version.
25 Nov 2013 Review for CIAO 4.6. No changes.
16 Dec 2014 Review for CIAO 4.7. No changes.
24 Oct 2019 Added banner with CSC2 incompatibility.
29 Oct 2019 Updated with CSC2 example.
09 Dec 2021 Review for CIAO 4.14. Removed prism for CIAO 4.14.