1302.2785
Extraordinary magnification of the ordinary type Ia supernova PS1-10afx
Quimby, ... Oguri, More, More, Tanaka, ... et al
SNIa 20x too bright to be at specz=1.3883, but lack obvious lens candidate. Lens is a SMBH of a low-mass DM halo?
Nature v595 n7438
A rapidly spinning supermassive black hole at the centre of NGC 1365
Broad X-ray emission lines from neutral and partially ionized Fe observed in active galaxies have been interpreted as fluorescence produced by the reflection of hard -rays off the inner edge of an accretion disk. In this model, line broadening and distortion result from rapid rotation and relativistic effects near the BH, the line shape being sensitive to its spin. Alternative models in which the distortions result from absorption by intervening structures provide an equally good description of the data, and there has been no general agreement on which is correct. Use NGC 1365, whose SMBH has recently been claimed to have maximum possible rotation (from relativistic reflection). Report X-ray observations of NGC 1365 that reveal the relativistic disk features through broadened Fe-line emission and an associated Compton scattering excess of 10-30 keV. Using temporal and spectral analysis, disentangle continuum changes due to time-variable absorption from reflection, ... [I don't understand the physical reasoning how reflection can be distinguished from absorption, except for the model fitting in the paper]
1302.3243
The cosmic evolution of faint satellite galaxies as a test of galaxy formation and the nature of dark matter
Nierenberg, Treu, Menci, Lu, Wang
LCDM predicts a large number of subhaloes for each galaxy-size halo; observations vs simulation poses challenges to astrophysics of galaxy formation. Show that cosmic evolution and host mass dependence of the luminosity function of satellite provides a powerful new diagnostic to disentangle astrophysical effects from variations in the underlying DM mass function.
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