2XMMp clusters in the SDSS

Georg Lamer

Axel Schwope

Jan Kohnert

Extended sources in 2XMMp

• Total extended sources: 6271• Selections:

– offax > 4 arcmin, all EPIC full frame– abs (bII) > 20o , ext_ml > 5

• Remaining: 2136 • In SDSS DR5 footprint: 867• Unique: 569• After visual screening: 411

Correlation with SDSS

• Select SDSS galaxies within 1 arcmin of 411 X-ray positions– photometry (ugriz), photometric redshifts– spectra, spectroscopic redshifts– colour thumbnail images

• Visual inspection of images, spectroscopic and photoscopic redshifts

Correlation with SDSS

Spectroscopic z = 0.223

Correlation with SDSS

photometric < z > = 0.38 (11 galaxies)

Results

• Sources investigated: 411

• No SDSS products: 12

• Spectroscopic redshifts: 116

• Photometric redshifts: 131

• Total SDSS redshifts: 247

photo-z / spectroscopic z

BCG colours

X-ray luminosities

Hardness ratios

Redshift distribution

Effects of large scale structure?

0.2

0.4

z

R.A.

120O

180O

240O