We test the viability of the Higgs-dilaton model ( HDM ) compared to the evolving dark energy ( w _ { 0 } w _ { a } CDM ) model , in which the cosmological constant model \Lambda CDM is also nested , by using the latest cosmological data that includes the cosmic microwave background temperature , polarization and lensing data from the Planck satellite ( 2015 data release ) , the BICEP and Keck Array experiments , the Type Ia supernovae from the JLA catalog , the baryon acoustic oscillations from CMASS , LOWZ and 6dF , the weak lensing data from the CFHTLenS survey and the matter power Spectrum measurements from the SDSS ( data release 7 ) .
We find that the values of all cosmological parameters allowed by the Higgs-dilaton inflation model are well within the Planck satellite ( 2015 data release ) constraints .
In particular , we have that w _ { 0 } = -1.0001 ^ { +0.0072 } _ { -0.0074 } , w _ { a } = 0.00 ^ { +0.15 } _ { -0.16 } , n _ { s } = 0.9693 ^ { +0.0083 } _ { -0.0082 } , \alpha _ { s } = -0.001 ^ { +0.013 } _ { -0.014 } and r _ { 0.05 } = 0.0025 ^ { +0.0017 } _ { -0.0016 } ( 95.5 % C.L . ) .
We also place new stringent constraints on the couplings of the Higgs-dilaton model and we find that \xi _ { \chi } < 0.00328 and \xi _ { h } / \sqrt { \lambda } = 59200 ^ { +30000 } _ { -20000 } ( 95.5 % C.L . ) .
Furthermore , we report that the HDM is at a slightly better footing than the w _ { 0 } w _ { a } CDM model , as they both have practically the same chi-square , i.e . \Delta \chi ^ { 2 } = \chi ^ { 2 } _ { w _ { 0 } w _ { a } \mathrm { CDM } } - \chi ^ { 2 } _ { \mathrm { HDM } } = 0.18 , with the HDM model having two fewer parameters .
Finally Bayesian evidence favors equally the two models , with the HDM being preferred by the AIC and DIC information criteria .