Volume 565, May 2014
|Number of page(s)||6|
|Published online||27 May 2014|
Scientific observations of HE0435-1223.
Flux ratios of the HE0435-1223 components measured at several epochs (compiled from the literature).
For MD/B ~ 0.7 (and μ ~ 1.1 in the continuum), the whole line profile would be affected by microlensing so that a rigorous MmD cannot be performed. Simultaneous micro-magnification of the Hα red wing (although to a lesser extent than for MD/B ~ 0.5) and micro-de-magnification of the blue wing would reproduce the distortions observed in the Hα line profile of image D (red curve in Fig. A.1). Caustics can cause such microlensing effect since they can delineate magnification and de-magnification areas.
For MD/B ~ 0.8, only the blue wing of Hα is micro-de-magnified (magenta curve in Fig. A.1) and the continuum is not microlensed (μ ~ 1 in the continuum). A similar microlensing effect that magnifies only the broad emission line region, has presumably been observed for the system J1004-4142 (Richards et al. 2004). In that interpretation, a de-magnification area stands close enough to affect the BLR but far enough not to affect the continuum source. This agrees with the stability of the D/B flux ratio over time and wavelength (see Table 3). However, considering the unification model for active galactic nuclei, in which a dusty torus surrounds the BLR (regardless of its geometry), we would expect a broad de-magnification region to de-magnify the dusty torus as well. Thus, the L′-band flux should be affected, which is not observed.
Ratio between the Hα line profiles observed in the spectrum of image D and the spectrum of image B, corrected for the macro-magnification ratio. The continua that compose the spectra of images B and D were previously subtracted. This ratio is a proxy for the effect of microlensing on the Hα line profile in D. At a given wavelength, a ratio higher than unity corresponds to the micro-magnification of the BLR emission. Conversely, a lower ratio indicates a micro-de-magnification. The spectra were smoothed with a fifteen-pixel-wide median filter for clarity.
|Open with DEXTER|
© ESO, 2014
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.