Probing the Broad-line Region and the Accretion Disk in the Lensed Quasars HE 0435-1223, WFI 2033-4723, and HE 2149-2745 Using Gravitational Microlensing

Motta, V.; Mediavilla, E.; Rojas, K.; Falco, E. E.; Jiménez-Vicente, J.; Muñoz, J. A.
Referencia bibliográfica

The Astrophysical Journal, Volume 835, Issue 2, article id. 132, 13 pp. (2017).

Fecha de publicación:
2
2017
Número de autores
6
Número de autores del IAC
1
Número de citas
35
Número de citas referidas
33
Descripción
We use single-epoch spectroscopy of three gravitationally lensed quasars, HE 0435-1223, WFI 2033-4723, and HE 2149-2745, to study their inner structure (broad-line region [BLR] and continuum source). We detect microlensing-induced magnification in the wings of the broad emission lines of two of the systems (HE 0435-1223 and WFI 2033-4723). In the case of WFI 2033-4723, microlensing affects two “bumps” in the spectra that are almost symmetrically arranged on the blue (coincident with an Al iii emission line) and red wings of C iii]. These match the typical double-peaked profile that follows from disk kinematics. The presence of microlensing in the wings of the emission lines indicates the existence of two different regions in the BLR: a relatively small one with kinematics possibly related to an accretion disk, and another one that is substantially more extended and insensitive to microlensing. There is good agreement between the estimated size of the region affected by microlensing in the emission lines, {r}s={10}-7+15\sqrt{M/{M}ȯ } lt-day (red wing of C iv in HE 0435-1223) and {r}s={11}-7+28\sqrt{M/{M}ȯ } lt-day (C iii] bumps in WFI 2033-4723), and the sizes inferred from the continuum emission, {r}s={13}-4+5\sqrt{M/{M}ȯ } lt-day (HE 0435-1223) and {r}s={10}-2+3\sqrt{M/{M}ȯ } lt-day (WFI 2033-4723). For HE 2149-2745 we measure an accretion disk size {r}s={8}-5+11\sqrt{M/{M}ȯ } lt-day. The estimates of p, the exponent of the size versus wavelength ({r}s\propto {λ }p), are 1.2 ± 0.6, 0.8 ± 0.2, and 0.4 ± 0.3 for HE 0435-1223, WFI 2033-4723, and HE 2149-2745, respectively. In conclusion, the continuum microlensing amplitude in the three quasars and chromaticity in WFI 2033-4723 and HE 2149-2745 are below expectations for the thin-disk model. The disks are larger and their temperature gradients are flatter than predicted by this model.
Proyectos relacionados
Imagen del Proyecto
Astrofísica Relativista y Teórica
El estudio de las lentes gravitatorias proporciona poderosas herramientas en Astrofísica y Cosmología. Las principales aplicaciones de las lentes gravitatorias en las que se centra este proyecto son las siguientes: (i) estudiar la presencia de subestructura de materia obscura en las galaxias lente a partir de las anomalías en la magnificación de
Evencio
Mediavilla Gradolph