Clusters of Galaxies

Coma cluster as seen by RoSat (from http://www.usm.uni-muenchen.de/people/saglia/dm/galaxien/alldt/node38.html)

Rosat PSPC details and curious story.

As seen by XMM (from http://xmm.esac.esa.int/external/xmm_science/gallery/public/level3.php?id=47&td='y')

See A comparison on the same scale.

Core as seen by Chandra

Virgo as seen by RoSat (note "relaxed" vs "unrelaxed")

Typical clusters not so impressive compared to Coma at z=0.023 (convert redshift to distance here or here).

NED

Coma spectrum from HEAO-1 (Henriksen and Mushotsky 1986).

Temperature maps:

• Temp. map of Fornax cluster (scroll down).
• Temp. map of Abell 2255 (scroll downto Abell 2255).
• Perseus temp. map
• same with a colorbar.

Simulations of merging clusters.

Most famous merging cluster.

Shocks and cold fronts in galaxy clusters, a rewview by Markevitch and Vikhlinin (2007), see esp. pp. 10 and 14.

cD galaxies: picture of Abell 740 on wikipedia. Can be Mpc across! Light profile at NED.

What about non-merging clusters? See LoCUSS paper p. 32ff

Cosmology with Clusters

Cluster Mass Function

Cluster mass function growth with redshift from Vikhlinin et al (2007). Black: 0.025

Cluster constraints on dark energy from Majumdar and Mohr (2004). Their caption: Fig. 2.-- Constraints on w and M for an SZE SPT survey (top), SZE Planck survey (middle) and an X-ray DUET survey (bottom). Contours denote joint 1- constraints in five scenarios: constraints from dN/dz for `Only Cosmology' case (i­dotted) ; constraints from dN/dz for `Non-Std Evol' case (ii­long­dashed); constraints from ¯ dN/dz + Pcl , (iii­dot­dashed); dN/dz + 100 cluster follow-up (iv­ ¯ short­dashed) and the finally constraints from dN/dz+ Pcl + follow- up (v­solid). Note, that for the Planck survey, for the `Non-Std Evol' scenario (i.e long­dashed), the constraint ellipse is too large and lies outside the range for the two axes. A flat universe is assumed for all the cases. The different terms are described in the text.

Aside on SZE

From http://astro.uchicago.edu/sza/primer.html, a nice primer on SZE.

Shift in spectrum, from same site.

Residual spectrum from bolo.berkeley.edu.

(Almost) redshift independence! From chicago.edu site (and Carlstrom et al ARAA 2002).

End of aside on SZE

Cluster constraints on sigma8 from Majumdar and Mohr (2004).

Caution: must know selection function very well!

Cosmology with f_gas

f_gas(z) for two cosmologies from Allen et al (2004). Which one is the true cosmology?

Caution! from the same paper.

Cosmological constraints from the same paper. "Breaking degeneracies, checking foundations."

X-ray Scaling Relations

From Rosati et al 2002, ARAA 40, 539, Fig 2.

Also from Rosati et al 2002, ARAA, Fig 2.

From same paper, Fig 3, simulated effect of preheating.

Scaling relations from Dave' et al (2002, ApJ 579, 23) hydro simulations, Fig. 1 (zero metallicity).

Scaling relations from Dave' et al (2002, ApJ 579, 23) hydro simulations, Fig. 8 (cosmic metallicity).

Dave' et al Fig. 3 shows effect of clumping (dotted segement connecting points) and hot gas fraction (solid segments). Dotted line: self-similar prediction. Solid line: best fit to open points (corrected for clumping/hot gas fraction effects), slope 2.4.

X-ray Selected Cluster Samples

MACS, Ebeling et al