Astronomy and Astrophysics – Astrophysics
Scientific paper
1996-08-29
Astronomy and Astrophysics
Astrophysics
34 pages text, 17 figures, figures also available at http://lheawww.gsfc.nasa.gov/~caleb/warps/warps.html Accepted for publica
Scientific paper
10.1086/303698
We have embarked on a survey of ROSAT PSPC archival data with the aim of detecting all significant surface brightness enhancements due to sources in the innermost 15 arcmin of the PSPC field of view (0.5-2.0 keV). This project is part of the Wide Angle ROSAT Pointed Survey (WARPS) and is designed primarily to measure the low luminosity, high redshift, X-ray luminosity function of galaxy clusters and groups. The approach we have chosen for source detection [Voronoi Tessellation and Percolation (VTP)] represents a significant advance over conventional methods and is particularly suited for the detection and accurate quantification of extended and/or low surface brightness emission. In an extensive optical follow-up programme we are identifying galaxies, groups and clusters at redshifts ranging from z~0.1 to z~0.7. We present first results for an initial 17.2 deg^2 at detected fluxes > 3.5 x 10^-14 erg s^-1 cm^-2. We find the sky density of extended objects to be in the range 2.8 to 4.0 (+- 0.4) deg^-2. A comparison with a point source detection algorithm demonstrates that our VTP approach typically finds 1-2 more objects deg^-2 to this detected flux limit. The surface brightness limit of the WARPS cluster survey is ~1x10^-15 erg sec^-1 cm^-2 arcmin^-2, approximately 6 times lower than the EMSS. The WARPS LogN-LogS shows a significant excess over previous measurements for S > 8 x 10^-14 erg sec^-1 cm^-2.
Ebeling Harald
Jones Robert L.
Malkan Matthew
Perlman Eric
Scharf Caleb. A.
No associations
LandOfFree
The WARPS X-ray survey of galaxies, groups and clusters I: Method and first results does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The WARPS X-ray survey of galaxies, groups and clusters I: Method and first results, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The WARPS X-ray survey of galaxies, groups and clusters I: Method and first results will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-81669