Chandra X-Ray Observatory
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Last modified: 26 October 2016

URL: http://cxc.harvard.edu/ciao/data_products_guide/image.html

Images

Data Products Guide

Filename Description Content SDP Pipeline
acis_cntr_img2.fits high-resolution image
of the center of the field
HIRESIMG ACIS2
hrc_cntr_img2.fits high-resolution image
of the center of the field
HIRESIMG HRC2
acis_full_img2.fits full-field sky image LORESIMG ACIS2
hrc_full_img2.fits full-field sky image LORESIMG HRC2

The creation process for the two types of images in the same for ACIS and HRC.


High-resolution Image

Filename Description Content SDP Pipeline
acis_cntr_img2.fits high-resolution image
of the center of the field
HIRESIMG ACIS2
hrc_cntr_img2.fits high-resolution image
of the center of the field
HIRESIMG HRC2

Description:

A 1024x1024 pixel image of the center of the field at full resolution (~0.5 arcsec/pixel). The field is centered at the target position of the observation. This image is created from the level=2 event file, which is filtered for bad pixels, bad times, etc. The array axes are specified in sky(x,y) coordinates (for more information, see the coords ahelp file).

Creator pipeline: acis_L2

dmcopy - the image may be recreated by using dmcopy on the level=2 event file with a region of 1024x1024 pixels centered at the target position.

unix% dmcopy "evt2.fits[sky=region(field.reg)]" image.fits

IMAGE-specific columns:

Column Name Units Description
IMAGE[1024,1024] counts an array of the counts

Full-field Sky Image

Filename Description Content SDP Pipeline
acis_full_img2.fits full-field sky image LORESIMG ACIS2
hrc_full_img2.fits full-field sky image LORESIMG HRC2

Description:

An image of the whole field of an observation, centered at the target position of the observation. The image size depends on the detector:

Detector Bin Factor Image Size (pixels)
ACIS 8 1024x1024
HRC-I 32 1024x1024
HRC-S 32 2048x2048

The array axes are specified in sky(x,y) coordinates (for more information, see the coords ahelp file).

Creator pipeline: acis_L2

dmcopy - the image may be recreated by using dmcopy on the level=2 event file with the binning from the table, above.

unix% dmcopy "acis_evt2.fits[bin sky=8]" acis_image.fits

IMAGE-specific columns:

Column Name Units Description
IMAGE[1024,1024] counts an array of the counts

Last modified: 26 October 2016
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