Multi-phase investigation of outflows in the circumgalactic and interstellar media of luminous quasars at <i>z</i> ∼ 5
Bibliographic record
Abstract
Aims. Outflows from active galactic nuclei are invoked as the principal feedback process regulating the co-evolution of supermassive black holes and their host galaxies. Because of their multi-phase and multi-scale nature, an exhaustive description of these winds should exploit multiple tracers. However, connecting various outflow features remains a challenge. The aim of this work is to provide a complete characterisation of outflows in a sample of z ∼ 5 quasars, by exploiting the combination of different emission and absorption tracers. Methods. We analysed the UV/optical and FIR continuum, line emission, and absorption in a sample of 39 z ∼ 5 quasars observed with VLT/X-Shooter and ALMA (available for six objects). We identified broad and narrow absorption lines associated with the quasar and emission lines to determine black hole masses and bolometric luminosities. Results. Our sample encompasses massive (MBH,Mg II = 108.5−10 M⊙) and luminous (Lbol = 1046.9 − 48 erg/s) quasars at redshift 5 − 5.7. They display powerful ionised outflows detected in both emission and absorption, with velocities exceeding 48 000 km s−1 in some cases, and lie above the local black hole – host galaxy mass relation, exhibiting a behaviour similar to that of z ≳ 6 quasars. These findings suggest a phase of efficient black hole feedback occurring at redshift z ≳ 6 and likely persisting down to z ∼ 5, characterised by rapid black hole growth exceeding that of the host galaxy. The fraction of quasars with outflow detections in absorption is higher for larger C IV-Mg II velocity shifts, suggesting that while the physical mechanisms powering the two outflow phenomena detected in emission and absorption may differ, a correlation exists between them.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".