Updated Cosmological Constraints from 2D BAO Measurements: A New Compilation and Comparison with DESI DR2

Abstract

We investigate and update observational constraints on cosmological parameters within the $\Lambda$CDM and dynamical dark energy frameworks, using a new compilation of the transverse (or 2D) BAO data, measurements that provide a relatively model-independent estimate of the BAO angular scale at a given redshift. Firstly, we assess the consistency of this compilation with CMB-Planck data and recent BAO results from the DESI collaboration. After confirming minimal tension with CMB data, we perform a series of joint analyses combining CMB data with the 2D~BAO compilation, as well as with several recent Type Ia supernova (SNIa) samples. In all cases, we compare the constraining power of the 2D~BAO data with that of DESI~DR2 data (3D~BAO). Our results indicate that combining 2D~BAO with CMB and SNIa data provides observational constraints that are in agreement with those obtained using DESI~DR2 data. Although the precision of DESI~DR2 results remains higher, as expected due to the more accurate 3D measurements, the 2D~BAO compilation combined with other probes yields strong constraints. For example, in the $\Lambda$CDM context, we find (CMB + 2D~BAO): $H_0 = 68.16^{+0.41}_{-0.37} \,\,\, \text{km s}^{-1}\,\text{Mpc}^{-1}$ and $\Sigma m_{\nu} < 0.081~\mathrm{eV}$ (95\%~CL). These results are consistent with analogous analyses using DESI~DR2. Several other cases are investigated and discussed in the main text. Our results show that this new 2D~BAO compilation is robust and delivers meaningful cosmological constraints. Parameters from 2D~BAO alone agree with CMB-only results, with no significant tension. Overall, 2D and 3D BAO provide consistent and complementary information when combined with other probes.