Updated observational constraints on φCDM dynamical dark energy cosmological models

We present updated observational constraints on the spatially flat ϕ CDM cosmological model, in which dark energy is described by a minimally coupled scalar field ϕ with an inverse power-law potential energy density V = V₀ϕ−α. Using a combination of Planck 2018 cosmic microwave background (CMB) temperature, polarization (P18), and lensing power spectra (lensing), along with a comprehensive compilation of non-CMB data including baryon acoustic oscillation, type Ia supernova, Hubble parameter and growth rate measurements, we analyze parameter constraints of the ϕ CDM and ϕ CDM+ A L models where A_L models where A_L is the CMB lensing consistency parameter. We find that the scalar field parameter α, which governs dark energy dynamics, is more tightly constrained by non-CMB data than by CMB data alone. From P18+lensing+nonCMB data, we obtain α 0.055±0.041 in the ϕ CDM model and α = 0.095± 0.056 in the ϕ CDM+ A_L model, mildly favoring evolving dark energy over a cosmological constant by 1.3 σ and 1.7σ. The estimated Hubble constant is H₀ = 67:55_-0.46^+0.53 km s¹ Mpc¹ for P18+lensing +non-CMB data in the ϕ CDM model, consistent with median statistics and some local determinations, but in tension with other local determinations. The constraints for matter density and clustering amplitude (Ω_m=0.3096±0.0055, σ₈ = 0:8013_-0.0067^+0.0077) of the ϕCDM model statistically agree with CDM model values. Allowing the CMB lensing consistency parameter A_L to vary reduces tensions between CMB and non-CMB data, although we find A_L = 1:105±0:037, 2:8σ higher than unity, consistent with the excess smoothing seen in Planck data. Model comparison using AIC and DIC shows that the ϕCDM model provides a fit comparable to CDM, with the ϕCDM+A_L extension slightly preferred in some cases. Overall, our results indicate that while the CDM model remains an excellent fit, current data leave open the possibility of mildly evolving quintessence-like dynamical dark energy, without a phantom-divide crossing.