dissecting Mg II, optical Fe II, and UV Fe II emission regions

Povzetek

Context. We present the wavelength-resolved reverberation mapping (RM) of combined Mg II and UV Fe II broad-line emissions for two intermediate-redshift (z ∼ 1), luminous quasars, HE 0413-4031 and HE 0435-4312, monitored by the Southern African Large Telescope (SALT) and 1m class telescopes between 2012 and 2022. Aims. Using a wavelength-resolved technique, we aim to disentangle the Mg II and Fe II emission regions and to build a radius–luminosity (R–L) relation for UV Fe II emission, which has so far remained unconstrained. Methods. We applied several time-delay methodologies to constrain the time delays for total Mg II and Fe II emissions. In addition, wavelength-resolved RM is performed to quantify the inflow or outflow of broad-line region (BLR) gas around the supermassive black hole and to disentangle the emission and the emitting regions based on lines produced in proximity to each other. Results. The mean total FeII time delay is nearly equal to the mean total MgII time delay for HE 0435-4312, suggesting the co-spatiality of their emission regions. However, in HE 0413-4031, the mean FeII time delay is found to be longer than the mean MgII time delay, suggesting that FeII emission is produced at greater distances from the black hole. The UV FeII R–L relation is updated with these two quasars (now four in total) and compared with the optical FeII relation (20 sources), which suggests that the optical FeII emission region is located further than the UV FeII region by a factor of 1.7–1.9, that is, RFeII-opt ∼ (1.7 − 1.9)RFeII-UV. Conclusion. Wavelength-resolved reverberation is an efficient way to constrain the geometry and structure of the BLR. We detected a weak pattern in the time delay versus wavelength relation, suggesting that the MgII broad line originates from a region slightly closer to the SMBH than the UV FeII pseudo continuum, although the difference is not very significant. Comparison of MgII, UV, and optical FeII R–L relations suggests that the difference may be greater for lower-luminosity sources, possibly with the MgII emission originating further from the SMBH. In the future, more RM data will be acquired, allowing better constraints on these trends, in particular the UV FeII R–L relation.

Ključne besede

accretion;accretion disks;emission lines;photometric;spectroscopic;

Podatki

Jezik: Angleški jezik
Leto izida:
Tipologija: 1.01 - Izvirni znanstveni članek
Organizacija: UNG - Univerza v Novi Gorici
UDK: 52
COBISS: 171872259 Povezava se bo odprla v novem oknu
ISSN: 1432-0746
Št. ogledov: 562
Št. prenosov: 4
Ocena: 0 (0 glasov)
Metapodatki: JSON JSON-RDF JSON-LD TURTLE N-TRIPLES XML RDFA MICRODATA DC-XML DC-RDF RDF

Ostali podatki

Vrsta dela (COBISS): Delo ni kategorizirano
Strani: str. 1-22
Letnik: ǂVol. ǂ678
Zvezek: ǂ[article no.] ǂA189
Čas izdaje: 2023
DOI: 10.1051/0004-6361/202346738
ID: 21815739
Priporočena dela:
, dissecting Mg II, optical Fe II, and UV Fe II emission regions
, systematic selection of tidal disruption events in iPTF
, ǂa ǂpopulation of extreme emission line galaxies at 1.7 [lesssim] z [lesssim] 6.7 selected with JWST medium band filters