Tootfinder

Quasar Main Sequence unfolded by 2.5D FRADO (Natural expression of Eddington ratio, black hole mass, and inclination)
M. H. Naddaf, M. L. Mart\'inez-Aldama, P. Marziani, B. Czerny, D. Hutsem\'ekers
https://arxiv.org/abs/2510.01092

Quasar Main Sequence unfolded by 2.5D FRADO (Natural expression of Eddington ratio, black hole mass, and inclination)
The quasar main sequence (QMS), characterized by the Eigenvector 1 (EV1), serves as a unifying framework for classifying type-1 active galactic nuclei (AGNs) based on their diverse spectral properties. Although a fully self-consistent physical interpretation has long been lacking, our physically motivated 2.5D FRADO (Failed Radiatively Accelerated Dusty Outflow) model naturally predicts that the Eddington ratio ($\dot{m}$) is the primary physical driver of the QMS, with black hole mass ($M_{\rm…

Probing the H0 Tension with Holographic Dark Energy in Unimodular Gravity: Insights from DESI DR2
Francisco Plaza, Gabriel Le\'on, Lucila Kraiselburd
https://arxiv.org/abs/2508.21175

Probing the H0 Tension with Holographic Dark Energy in Unimodular Gravity: Insights from DESI DR2
Motivated by the recent baryon acoustic oscillation measurements of DESI DR2 collaboration, this works presents an extended analysis of a cosmological model based on holographic dark energy within the framework of Unimodular Gravity. We probe the model with an extensive set of observations: cosmic chronometers, Pantheon Plus$+$SH0ES Type Ia supernovae, DESI DR2 BAO distances, quasar X-ray/UV fluxes (two independent calibrations), and Planck 2018 CMB data. The results are analyzed to assess the …

First constraints on the local ionization topology in front of two quasars at z ~ 7.5
Timo Kist, Joseph F. Hennawi, Frederick B. Davies, Eduardo Ba\~nados, Sarah E. I. Bosman, Zheng Cai, Anna-Christina Eilers, Xiaohui Fan, Zolt\'an Haiman, Hyunsung D. Jun, Yichen Liu, Jinyi Yang, Feige Wang
https://arxiv.org/abs/2508.21818

First constraints on the local ionization topology in front of two quasars at z ~ 7.5
Thus far, Lyman-$α$ damping wings towards quasars have been used to probe the \textit{global} ionization state of the foreground intergalactic medium (IGM). A new parameterization has demonstrated that the damping wing signature also carries \textit{local} information about the distribution of neutral hydrogen (HI) in front of the quasar before it started shining. Leveraging a recently introduced Bayesian \texttt{JAX}-based Hamiltonian Monte Carlo (HMC) inference framework, we derive constrain…