The Lockman-SpReSo Project. Spectroscopic Analysis of Type 1 Active Galactic Nuclei

Negrete, Castalia Alenka; Ibarra-Medel, Héctor J.; Benítez, Erika; Cruz-González, Irene; Krongold, Yair; González, J. Jesús; Cepa, Jordi; Padilla-Torres, Carmen; Cerviño, Miguel; Povic, Mirjana; Herrera-Endoqui, Martín; Jenaro-Ballesteros, Nancy; Miyaji, Takamitsu; Elías-Chávez, Mauricio; Sánchez-Portal, Miguel; Cedrés, Bernabé; Nadolny, Jakub; González-Otero, Mauro; Assefa, Bereket; Hernández-Toledo, Héctor; de Diego, J. Antonio; González-Serrano, J. Ignacio; Pérez-García, A. M.
Bibliographical reference

The Astrophysical Journal

Advertised on:
9
2025
Number of authors
23
IAC number of authors
4
Citations
0
Refereed citations
0
Description
We present the first optical-UV spectral systematic analysis of 30 Type 1 active galactic nuclei selected in the far-infrared and X-ray in the Lockman-SpReSO Survey. The sample of faint objects (mB = 19.6–21.8) covers a large redshift range of 0.33 >z > 4.97 with a high signal-to-noise ratio (∼21 on average). A detailed spectral analysis based on the quasar main-sequence phenomenology prescription was applied to deblend the principal optical-UV emitting regions. Our sample spans a bolometric luminosity range of 44.85 < logLbol < 47.87, absolute B-magnitude of 20.46 >MB > –26.14, BH mass of 7.59 < logMBH < 9.80, and Eddington ratio of –1.70 < logREdd < 0.56. The analysis shows that 18 high-z objects correspond to Population (Pop) B, whereas three low-z fall in Pop A2, B1, and B1+. The remaining eight are candidates to be Pop B and one Pop A object. None of them is an extreme accretor. We looked for tendencies in our sample and compared them with other samples with different selection criteria. Evidence for winds was explored using the C IVλ1549 line half-height centroid c(1/2), finding wind velocities between 941 and ‑1587 km s‑1. This result is consistent with samples with similar ranges of z and MB. The Baldwin effect showed a slope of –0.23 ± 0.03 dex consistent with previous studies. Spectra from 12 objects in our sample were found in the Sloan Digital Sky Survey Data Release 17 database. We applied the same methodology to compare them to our spectra, finding no evidence of variability.