We use single-epoch spectroscopy of three gravitationally lensed quasars , HE0435-1223 , WFI2033-4723 , and HE2149-2745 , to study their inner structure ( BLR and continuum source ) .
We detect microlensing-induced magnification in the wings of the broad emission lines of two of the systems ( HE0435-1223 and WFI2033-4723 ) .
In the case of WFI2033-4723 , microlensing affects two “ bumps ” in the spectra which 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 ^ { +15 } _ { -7 } \sqrt { M / M _ { \odot } } light-days ( red wing of C iv in HE0435-1223 ) and r _ { s } = 11 ^ { +28 } _ { -7 } \sqrt { M / M _ { \odot } } light-days ( C iii ] bumps in WFI2033-4723 ) with the sizes inferred from the continuum emission , r _ { s } = 13 ^ { +5 } _ { -4 } \sqrt { M / M _ { \odot } } light-days ( HE0435-1223 ) and r _ { s } = 10 ^ { +3 } _ { -2 } \sqrt { M / M _ { \odot } } light-days ( WFI2033-4723 ) .
For HE2149-2745 we measure an accretion disk size r _ { s } = 8 ^ { +11 } _ { -5 } \sqrt { M / M _ { \odot } } light-days .
The estimates of p , the exponent of the size vs. wavelength ( r _ { s } \propto \lambda ^ { p } ) , are 1.2 \pm 0.6 , 0.8 \pm 0.2 , and 0.4 \pm 0.3 for HE0435-1223 , WFI2033-4723 , and HE2149-2745 , respectively .
In conclusion , the continuum microlensing amplitude in the three quasars and chromaticity in WFI2033-4723 and HE2149-2745 are below expectations for the thin disk model .
The disks are larger and their temperature gradients are flatter than predicted by this model .