README

ENTER THE XXLDB

(Last update December 2021)

Contact

Contact for the XXL DB (all matters): Tatyana.Sadibekova at cea.fr

Note

Before retrieving a cluster sample, please read:

• the general documentation on the DB,
• the description of the catalogue columns.

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Energy Conversion Factors

We provide below ECFs to convert the measured count-rates into fluxes for the [0.5-2] keV band.
Warning: given the mild ECF dependence on cluster spectrum or redshift, these values are sufficient for the purpose of proposal writing but not for scientific publications.

Proposed mean conversion factors (F. Pacaud - January 2013)
Assuming z=0.3, T=2 keV, Abundances =0.3 (APEC model)

• LSS [Nh=2.3 E+20]
  0.002015 MOS c/s  ==> 1e-14 erg/cm2/s   and   0.007031 PN c/s  ==> 1e-14 erg/cm2/s

• BCS [Nh=1.25 E+20]
  0.002008 MOS c/s  ==> 1e-14 erg/cm2/s   and  0.007045 PN c/s  ==> 1e-14 erg/cm2/s

NB the count-rate is for MOS1.
Hence, as a rule of thumb: a total count-rate of ~ 0.01 c/s in the [0.5-2] keV band corresponds to a flux of  ~ 1e-14 erg/s/cm2 in the same band; that is ~ 100 photons for 10 ks.

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README archive

June 2014
June 2013
December 2012
August 2011