Searcharxiv⌕ Search
Home/Archive/arXiv

arXiv · 2610.10267

A relativistic inflow candidate in a quasar at cosmic noon

Yerong Xu·Xiurui Zhao·Elena Bertola·Valentina Braito·Francesca Civano·Luca Comisso·Luigi Gallo·Vittoria E. Gianolli·Elias Kammoun·Giorgio Lanzuisi·Stefano Marchesi·Mar Mezcua·Ciro Pinto·James N. Reeves·Daniele Rogantini·Núria Torres-Albà·Lizhong Zhang
View original source ↗Read source document ↗Export metadata ↓

Abstract

Cosmic noon ($z\sim2$) marks the peak epoch of cosmic star formation and black hole accretion activity, where strong accretion and outflows are expected. We report two candidate absorption features in the \textit{XMM-Newton} spectrum of the quasar WISEA~J094835.95+432302.6 at $z=1.893$. Two redshifted features occur at rest-frame energies of $\sim4.65$ and $\sim5.75$keV with confidence levels of 99.3% and 94.1%, respectively, estimated from Monte Carlo (MC) simulations considering the look-elsewhere effect. These features can be explained by the Fe XXV/XXVI K-shell transitions from one ultra-fast inflow (UFI) with an apparent velocity of $0.37^{+0.02}_{-0.01}c$. If confirmed by follow-up \textit{XMM-Newton} observations, these detections would extend reported UFI candidates from the local Universe to cosmic noon, offering a rare laboratory for black hole accretion at the peak of their growth.

Explore related subjects

astro-ph.HE

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Yerong Xu, Xiurui Zhao, Elena Bertola, Valentina Braito, Francesca Civano, Luca Comisso, Luigi Gallo, Vittoria E. Gianolli, Elias Kammoun, Giorgio Lanzuisi, Stefano Marchesi, Mar Mezcua, Ciro Pinto, James N. Reeves, Daniele Rogantini, Núria Torres-Albà, Lizhong Zhang. 2026-10-07. A relativistic inflow candidate in a quasar at cosmic noon. https://arxiv.org/abs/2610.10267

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Revising the Spin and Kick Connection in Isolated Binary Black Holes

The origin of black hole (BH) spins remains one of the least understood aspects of BHs. Despite many uncertainties, it is commonly assumed that if BHs originated from isolated massive star binaries, their spins should be aligned with the orbital angular momentum of the binary system. This assumption stems from the notion that BHs inherit their spins from their progenitor stars. In this study, we relax this long-held viewpoint and explore various mechanisms that can spin up BHs before or during their formation. In addition to natal spins, we discuss physical processes that can spin BHs isotropically, parallel to natal kicks, and perpendicular to natal kicks. These different mechanisms leave behind distinct imprints on the observable distributions of spin magnitudes, spin-orbit misalignments and the effective inspiral spin of merging binaries. In particular, these mechanisms allow even the binaries originating in the field to exhibit precession and retrograde spin ($χ_{\rm eff}<0$). This broadens the parameter space allowed for isolated binary evolution into regimes which were previously thought to be exclusive to dynamically assembled binaries.

astro-ph.HE↗
arXiv2026

Collisionless Accretion of Finite-Angular-Momentum Plasma onto a Spinning Black Hole

In low-luminosity active galactic nuclei like M87* and Sgr A*, the accretion disk around the central supermassive black hole is tenuous and collisionless. As a result, the usual ideal magnetohydrodynamics (MHD) approximation may not be applicable. In this Letter, we report on the first fully kinetic simulations of the accretion process where the plasma initially has finite angular momentum, focusing on the case of axisymmetry. The simulated accretion flow behaves remarkably similarly to the magnetically arrested disk (MAD) regime of ideal MHD, reproducing episodes of magnetic flux saturation and eruption typical of MADs. The resemblance to fluid models owes largely to kinetic instabilities, which regulate pressure anisotropy in the disk, allowing fluid terms to dominate the angular momentum transfer. In addition, by handling vacuum regions effectively, our kinetic approach probes the matter supply to the jet funnel. We observe no efficient penetration of the accreting material into this region, suggesting that a pair discharge may be required to sustain the Blandford-Znajek process. These initial findings represent important groundwork to be checked and built upon by future kinetic accretion simulations, especially in 3D.

astro-ph.HE↗
arXiv2026

Relaxation of a Vlasov gas to an inhomogeneous state due to phase space mixing in an axisymmetric potential: A Newtonian analogy of the Kerr orbital motion

We explore the dynamics of a Vlasov gas propagating in an external axisymmetric potential consisting of a central potential with an additional quadrupolar component which gives rise to two potential wells along the symmetry axis. Employing independently $N$-particle simulations and statistical methods, we show that an initially homogeneous and isotropic configuration evolves to an inhomogeneous final state with overdensities located at the wells. The quadrupolar component is chosen such that the equations of motion form an integrable Hamiltonian system, which allows one to compute the final state of the gas analytically. On the one hand, this allows one to compare the late-time behaviour of the simulations with an analytic prediction and on the other hand to understand the relaxation process through phase space mixing. Our model constitutes a Newtonian analogue of the particle motion in a Kerr spacetime, and we discuss possible applications to recently observed astrophysical phenomena.

astro-ph.HE↗