Understanding micro-image configurations in quasar microlensing
نویسندگان
چکیده
منابع مشابه
Quasar Image Shifts due to Gravitational Microlensing
Gravitational microlensing of quasars by stars in external galaxies can introduce fluctuations in the centroid of the “point-like” macro–images. The induced shifts are extremely small, on micro–arcsecond scales, below the limits of current optical observations. However, such shifts will become measurable with the proposed “Space Interferometry” mission, due to fly in 2005. The degree of the cen...
متن کاملUnambiguous quasar microlensing
Microlensing studies of quasars can reveal dark matter lumps over a broad mass spectrum; we highlight the importance of monitoring quasars which are seen through the halos of low-redshift galaxies. For these configurations microlensing by planetary-mass objects will manifest itself as isolated events which are only weakly chromatic. Statistical comparison of the observed optical depths with the...
متن کاملAbsorbing “Cloudlets” with Quasar Microlensing
Intergalactic Mg II absorbers are known to have structures down to scales ∼ 10pc, and there are now indications that they may be fragmented on scales . 10pc (Hao et al., astro-ph/0612409). I show that quasar microlensing can effectively probe Mg II and other absorption “cloudlets” with sizes ∼ 10 − 10pc by inducing significant spectral variability on the timescales of months to years. With nume...
متن کاملSignatures of Accretion Disks in Quasar Microlensing
We propose that relative variability on short time-scales of the multiple images of a lensed quasar, after removal of the time delay, may be caused by hot spots or other moving structures in the accretion disk crossing microlens caustics caused by stellar mass objects in the lensing galaxy. Such variability has been reported in the two images of 0957+561. The short durations would be due to the...
متن کاملImaging a Quasar Accretion Disk with Microlensing
We show how analysis of a quasar high-magnification microlensing event may be used to construct a map of the frequency-dependent surface brightness of the quasar accretion disk. The same procedure also allows determination of the disk inclination angle, the black hole mass (modulo the caustic velocity), and possibly the black hole spin. This method depends on the validity of one assumption: tha...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2010
ISSN: 0035-8711
DOI: 10.1111/j.1365-2966.2010.17797.x