WCSTools

imtmc
Find 2MASS Point Sources in an Image Region

 WCSTools programs
imtmc is a link to the WCSTools imcat utility which finds all of the 2MASS Point Source Catalog objects in a FITS or IRAF image and lists their sky and image positions. World coordinate system (WCS) information must be present in the image header to describe, in a standard way, the relationship between sky coordinates and image pixels. This information is used by the program to find the region in the sky to search and to transform right ascension and declination sky coordinate pairs to image coordinate (X,Y) pairs. Output is sent to a file called filename.tmc and to standard output if the -v flag is set.

For the All-Sky Data Release, the 2MASS ID number is the 2MASS declination zone, starting with 0 at the South Pole and moving north 0.1 degree at a time, followed by the sequence number of the star within the RA-sorted zone catalog.

For the Second Incremental Data Release data, the 2MASS ID number is the 2MASS region number, which is not the RA in hours because some one-hour bands have multiple regions, followed by by the sequence number of the star within the region, to fill seven decimal places. The relationship between region number, catalog file, and RA is shown in this table.

Set the environment variable TMC_PATH or the variable tmccd in libwcs/tmcread.c. to the directory containing the region files

To search a rectangular or circular region on the sky, use stmc.

The minimum command line is 

imtmc FITS or IRAF filename
The same effect can be obtained by running 
imcat -c tmc FITS or IRAF filename

Command Line Arguments

Examples

List the 10 brightest 2MASS Point Source Catalog stars in a FITS image
List the 2MASS Point Source Catalog stars in a FITS image to a file
Plot 2MASS Point Source Catalog stars onto a FITS image

Last updated 18 June 2003 by Doug Mink dmink@cfa.harvard.edu

Telescope Data Center