Abstract
Taking into account the mass splittings between three active neutrinos, we investigate the impacts of dark energy on constraining the total neutrino mass by using recent cosmological observations. We consider two typical dark energy models, namely, the model and the holographic dark energy (HDE) model, which both have an additional free parameter compared with the model. We employ the Planck 2015 data of CMB temperature and polarization anisotropies, combined with low-redshift measurements on BAO distance scales, type Ia supernovae, the Hubble constant, and Planck lensing. Compared to the model, our study shows that the upper limit on becomes much looser in the model but much tighter in the HDE model. In the HDE model, we obtain the 95% confidence level upper limit for three degenerate neutrinos. This might be the most stringent constraint on by far, and it is on the verge of diagnosing the neutrino mass hierarchies in the HDE model. However, the difference of is still not significant enough to distinguish the neutrino mass hierarchies, even though the minimal of the normal hierarchy is slightly smaller than that of the inverted hierarchy.
- Received 2 August 2016
DOI:https://doi.org/10.1103/PhysRevD.94.083519
© 2016 American Physical Society