Planck 2015 results
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Table 1

Summary of SZ-mass scaling-law parameters (see Eq. (7)).

Parameter Value

log Y −0.19 ± 0.02
α a 1.79 ± 0.08
β b 0.66 ± 0.50
σ lnY c 0.173 ± 0.023



Except when specified, α is constrained by this prior in our one-dimensional likelihood over N(z), but left free in our two-dimensional likelihood over N(z,q).


We fix β to its central value throughout, except when examining modelling uncertainties in the Appendix.


The value is the same as in our 2013 analysis, given here in terms of the natural logarithm and computed from σlog Y = 0.075 ± 0.01.

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