Measuring the dynamical state of Planck SZ-selected clusters

In this project, I studied the dynamical state of a representative subsample of galaxy clusters detected by Planck with the SZ effect. I use as a dynamical indicator the projected offset between the peak of the X-ray emission and the brightest cluster galaxy (BCG) which is expected to be small for relaxed objects and larger for merging objects. I studied the distribution of our indicator in this sample and compare it to its distribution in X-ray selected samples (HIFLUGCS, MACS and REXCESS). The distributions are significantly different and the fraction of relaxed objects is smaller in the Planck sample (52±4%) than in X-ray selected samples (≃74%). I interpret this result as an indication of different selection effects affecting X-rays (e.g. "cool core bias") and SZ surveys of galaxy clusters.

The paper has been submitted to MNRAS. It is available on astro-ph.

Table 1 is available in machine readable formats:

Table 1 of the paper in .fits format (gzipped)

Table 1 - VOtable (gzipped)

Below some slides about this project: my presentation at the weekly group meeting of the Cosmology Group at Unimi (January 2016) and my Astrosiesta talk at IASF-Milano (September, early results: be careful, numbers and statistics have changed!)

Group Meeting Slides

Astrosiesta Slides

Per gli studenti di fisica (for students only):

tutto è iniziato con una tesi di laurea triennale nel 2012. Altre opportunità di tesi sono possibili su questo argomento.

 

The feelings I had when working in this project. (see Astrosiesta slides) 

when you play the game of thrones you win or you die 3