NuSTAR Reveals Relativistic Reflection But No Ultra-Fast Outflow In The Quasar PG 1211+143

TL;DR

This study used NuSTAR to observe quasar PG 1211+143, revealing relativistic disk reflection but no evidence of ultra-fast outflows, providing insights into black hole accretion and feedback mechanisms.

Contribution

First detailed NuSTAR observation of PG 1211+143 showing relativistic reflection without detecting ultra-fast outflows, refining understanding of quasar accretion processes.

Findings

Relativistic disk reflection spectrum clearly detected.

No significant ultra-fast outflow absorption features found.

Constraints on black hole spin are weak.

Abstract

We report on four epochs of observations of the quasar PG 1211+143 using NuSTAR. The net exposure time is 300 ks. Prior work on this source found suggestive evidence of an 'ultra-fast outflow' (or, UFO) in the Fe K band, with a velocity of approximately 0.1c. The putative flow would carry away a high mass flux and kinetic power, with broad implications for feedback and black hole-galaxy co-evolution. NuSTAR detects PG 1211+143 out to 30 keV, meaning that the continuum is well-defined both through and above the Fe K band. A characteristic relativistic disk reflection spectrum is clearly revealed, via a broad Fe K emission line and Compton back-scattering curvature. The data offer only weak constraints on the spin of the black hole. A careful search for UFO's show no significant absorption feature above 90% confidence. The limits are particularly tight when relativistic reflection is included. We discuss the statistics and the implications of these results in terms of connections between accretion onto quasars, Seyferts, and stellar-mass black holes, and feedback into their host environments.