Exploring neutrino mass and mass hierarchy in the scenario of vacuum energy interacting with cold dark matte

We investigate the constraints on total neutrino mass in the scenario of vacuum energy interacting with cold dark matter. We focus on two typical interaction forms, i.e., Q=βHρc and Q=βHρΛ. To avoid the occurrence of large-scale instability in interacting dark energy cosmology, we adopt the parameterized post-Friedmann approach to calculate the perturbation evolution of dark energy. We employ observational data, including the Planck cosmic microwave background temperature and polarization data, baryon acoustic oscillation data, a JLA sample of type Ia supernovae observation, direct measurement of the Hubble constant, and redshift space distortion data. We find that, compared with those in the ΛCDM model, much looser constraints onstraints are obtained in the Q=βHρΛ mode mν are obtained in the Q = βHρc model, whereas slightly tighter conl. Consideration of the possible mass hierarchies of neutrinos reveals that the smallest upper limit ofarchy mν appears in the degenerate hierarchy case. By comparing the values of χ~2 min, we find that the normal hiercase is favored over the inverted one. In particular,we find that the difference ？χ22 min ≡χIH;min-χ~2 NH;min〉 2 in the Q = βHρc model. In addition, we find that β = 0 is consistent with the current observations in the Q=βHρc model, and β 〈0 is favored at more than the 1σ level in the Q=βHρΛ model.

Exploring neutrino mass and mass hierarchy in interacting dark energy models

We investigate how the dark energy properties impact the constraints on the total neutrino mass in interacting dark energy（IDE）models. In this study, we focus on two typical interacting dynamical dark energy models, i.e., the interacting w cold dark matter（IwCDM） model and the interacting holographic dark energy（IHDE） model. To avoid the large-scale instability problem in IDE models, we apply the parameterized post-Friedmann approach to calculate the perturbation of dark energy. We employ the Planck 2015 cosmic microwave background temperature and polarization data, combined with low-redshift measurements on baryon acoustic oscillation distance scales, type Ia supernovae, and the Hubble constant, to constrain the cosmological parameters. We find that the dark energy properties could influence the constraint limits on the total neutrino mass. Once dynamical dark energy is considered in the IDE models, the upper bounds of ∑mν will be changed. By considering the values of χmin2 , we find that in these IDE models the normal hierarchy case is slightly preferred over the inverted hierarchy case; for example, ?χ2= 2.720 is given in the IHDE+∑mν model. In addition, we also find that in the Iw CDM+∑mν model β = 0 is consistent with current observational data inside the 1σ range, and in the IHDE+∑mν model β > 0 is favored at more than 2σ level.

Constraints on the sum of neutrino masses using cosmological data including the latest extended Baryon Oscillation Spectroscopic Survey DR14 quasar sample

We investigate the constraints on the sum of neutrino masses（Σmv） using the most recent cosmological data, which combines the distance measurement from baryonic acoustic oscillation in the extended Baryon Oscillation Spectroscopic Survey DR14 quasar sample with the power spectra of temperature and polarization anisotropies in the cosmic microwave background from the Planck 2015 data release. We also use other low-redshift observations,including the baryonic acoustic oscillation at relatively low redshifts, Type la supernovae, and the local measurement of the Hubble constant. In the standard cosmological constant A cold dark matter plus massive neutrino model,we obtain the 95% upper limit to be Σmv 〈0.129 eV for the degenerate mass hierarchy,Σmv 〈0.159 eV for the normal mass hierarchy, and Σmv 〈0.189 eV for the inverted mass hierarchy. Based on Bayesian evidence, we find that the degenerate hierarchy is positively supported, and the current data combination cannot distinguish between normal and inverted hierarchies. Assuming the degenerate mass hierarchy, we extend our study to non-standard cosmological models including generic dark energy, spatial curvature, and extra relativistic degrees of freedom, but find these models are not favored by the data.

Constraints on neutrino mass in the scenario of vacuum energy interacting with cold dark matter after Planck 2018

In this work,we investigate the constraints on the total neutrino mass in the scenario of vacuum energy interacting with cold dark matter(abbreviated as IACDM)by using the latest cosmological observations.We consider four typical interaction forms,i.e.Q=βHρde,Q=βHρc,Q=βH0ρde,and Q=βH0ρc,in the IACDM scenario.To avoid the large-scale instability problem in interacting dark energy models,we employ the extended parameterized post-Friedmann method for interacting dark energy to calculate the perturbation evolution of dark energy in these models.The observational data used in this work include the cosmic microwave background(CMB)measurements from the Planck 2018 data release,the baryon acoustic oscillation(BAO)data,the type Ia supernovae(SN)observation(Pantheon compilation),and the 2019 local distance ladder measurement of the Hubble constant H0 from the Hubble Space Telescope.We find that,compared with those in the ACDM+∑mv model,the constrains on∑mv are looser in the four IACDM+∑mv models.When considering the three mass hierarchies of neutrinos,the constraints on∑mv are tightest in the degenerate hierarchy case and loosest in the inverted hierarchy case.In addition,in the four IACDM+∑mv models,the values of coupling parameterβare larger using the CMB+BAO+SN+H0 data combination than that using the CMB+BAO+SN data combination,andβ>0 is favored at more than 1σlevel when using CMB+BAO+SN+H0 data combination.The issue of the H0 tension is also discussed in this paper.We find that,compared with the ACDM+∑mv model,the H0 tension can be alleviated in the IACDM+∑mv model to some extent.

Impacts of dark energy on constraining neutrino mass after Planck 2018

Considering the mass splittings of three active neutrinos,we investigate how the properties of dark energy affect the cosmological constraints on the total neutrino mass∑mv using the latest cosmological observations.In this paper,several typical dark energy models,including ACDM,wCDM,CPL,and HDE models,are discussed.In the analysis,we also consider the effects from the neutrino mass hierarchies,i.e.the degenerate hierarchy(DH),the normal hierarchy(NH),and the inverted hierarchy(IH).We employ the current cosmological observations to do the analysis,including the Planck 2018 temperature and polarization power spectra,the baryon acoustic oscillations(BAO),the type Ia supernovae(SNe),and the Hubble constant H0 measurement.In the ACDM+∑mv model,we obtain the upper limits of the neutrino mass∑mv<0.123 eV(DH),∑mv<0.156 eV(NH),and∑mv<0.185 eV(IH)at the 95%C.L.,using the Planck+BAO+SNe data combination.For the wCDM+∑mv model and the CPL+∑mv model,larger upper limits of∑mv are obtained compared to those of the ACDM+∑mv model.The most stringent constraint on the neutrino mass,∑mv<0.080 eV(DH),is derived in the HDE+∑mv model.In addition,we find that the inclusion of the local measurement of the Hubble constant in the data combination leads to tighter constraints on the total neutrino mass in all these dark energy models.