Abell 2147
This galaxy cluster contains mostly faint, small and scattered galaxies.
Radial Profile
The extraction regions were chosen based on an exposure corrected, combined GIS-2 and GIS-3 sky image. Reference sky coordinates from the literature were used as input to a centroid routine to determine the cluster center right ascension and declination. A radial emission profile was then constructed from this position. Note that this radial profile does not reflect the true cluster profile given the complicated PSF of the ASCA mirrors and the GIS detector. The background (and sigma of the background) was iterative determined by stepping inward from the end of the profile and averaging (using a three sigma clipping algorithm). The extraction region was chosen to be the radius at which the radial profile reached 5*sigma times the background level.
The radial profile is shown below. The red line is the background level. The blue line is the 5*sigma level. SIS extaction radii were set at 0.70 times the GIS extraction radius.
See also
References
- ^ "NED results for object ABELL 2147". NASA/IPAC Extragalactic Database (NED). Retrieved March 15, 2012.
- ^ Abell, George O.; Corwin, Harold G. Jr.; Olowin, Ronald P. (May 1989). "A catalog of rich clusters of galaxies". Astrophysical Journal Supplement Series. 70 (May 1989): 1–138. Bibcode:1989ApJS...70....1A. doi:10.1086/191333. ISSN 0067-0049.
- ^ ABELL 2147 Archived 2012-03-20 at the Wayback Machine, Archive of Chandra Cluster Entropy Tables, Michigan State University, retrieved 2012-03-31.
- ^ Notes on Obscure Galaxy Clusters, San Francisco Amateur Astronomers, retrieved 2012-03-31.
- ^ Bautz, L. P. (June 1972). "Redshifts for galaxies in and near Abell 2147" (PDF). Astronomical Journal. 77: 331–332, 401–402. Bibcode:1972AJ.....77..331B. doi:10.1086/111287. AAA007.160.030. Retrieved April 1, 2012.
- ^ "ABELL 2147 in 83074000". Archived from the original on 2016-03-06.
External links
- Image
- Numerous images Archived 2012-03-20 at the Wayback Machine from the Chandra X-ray Observatory
- Image showing location relative to other Abell clusters