TY  - JOUR
AU  - Di Valentino, E.
AU  - Gariazzo, S.
AU  - Giare, W.
AU  - Melchiorri, A.
AU  - Mena, O.
AU  - Renzi, F.
PY  - 2023
DA  - 2023//
TI  - Novel model-marginalized cosmological bound on the QCD axion mass
T2  - Phys. Rev. D
JO  - Physical Review D
SP  - 103528
EP  - 16pp
VL  - 107
IS  - 10
PB  - Amer Physical Soc
AB  - We present model-marginalized limits on mixed hot dark matter scenarios, which consider both thermal neutrinos and thermal QCD axions. A novel aspect of our analyses is the inclusion of small-scale cosmic microwave background (CMB) observations from the Atacama Cosmology Telescope (ACT) and the South Pole Telescope (SPT), together with those from the Planck satellite and baryon acoustic oscillation (BAO) data. After marginalizing over a number of well-motivated nonminimal background cosmologies, the tightest 95% Confidential Level (CL) upper bound we obtain is 0.21 eV, both for P m nu and ma, from the combination of ACT, Planck and BAO measurements. Restricting the analyses to the standard ?CDM picture, we find P m nu < 0.16 eV and ma < 0.18 eV, both at 95% CL Interestingly, the best background cosmology is never found within the minimal ?CDM plus hot relics, regardless of the datasets exploited in the analyses. The combination of Planck with either BAO, SPT or ACT prefers a universe with a nonzero value of the running in the primordial power spectrum with strong evidence. Small-scale CMB probes, both alone and combined with BAO, either prefer, with substantial evidence, nonflat universes (as in the case of SPT) or a model with a time varying dark energy component (as in the case of ACT).
SN  - 2470-0010
UR  - https://arxiv.org/abs/2212.11926
UR  - https://doi.org/10.1103/PhysRevD.107.103528
DO  - 10.1103/PhysRevD.107.103528
LA  - English
N1  - WOS:000999454300009
ID  - DiValentino_etal2023
ER  -