Authors note a new phenomenon: linear portions of quasar lightcurves have gradients that appear vary systematically with quasar redshift (higher z quasars have steeper gradients). Interesting if real: it could sharpen up QSO redshift estimation in cadenced imaging surveys beyond what you can do with the QSO colours.
Epic paper by Sluse et al, on high precision astrometry in lensed quasar systems. Attention optical astronomers! They deconvolve their images! And get very small error bars as a result. Interesting claim about being able to quantify the lens environment (the dreaded "external covergence"). This is the biggest systematic error in H0/w determination - great if we can reduce it further through improved lens modelling.
Daniel Mortlock talked me through this when I visited ICL recently, its a nice result, especially the deep GP trough. The survey paper (that preceded this one) was interesting too, for its treatment of detection probablity and completeness, worth a look for anyone interesting in finding (and not finding) things.
Discovery of a group of quasars which appear to form a structure over 1 Gpc across. This is much larger than any previously-suggested homogeneity scale in LambdaCDM.
Andy Lawrence suggests that the unaccounted for UV flux in AGN spectra could be coming from "clouds" of gas orbiting the black hole at ~10 Schwarzschild radii, and reflecting light as UV line emission which all gets blurred together to make a broad continuum due to the insane speeds involved.
I saw Andy yesterday at the Edinburgh sims workshop - he agreed that his clouds were probably shreds, but all that really matters is the filling factor and ionisation state, and the code he used to play around with it all is called "cloudy"... I told him we found the model pretty plausible (stuff comes off accretion disks and stays in orbit, absorbing and emitting, fine), his hope is that someone makes a more detailed model, checks his results and does some inference. That'll be Lance then...
There's been quite a bit of discussion about this issue this summer, it came up at the Bologna dark matter meeting as well as the Aosta strong lensing workshop. Basically, in strong lens systems we infer *more* subhalos/satellites than CDM predicts for massive lens galaxies (the satellites cause "millilensing", where the quasar/radio source image fluxes are affected by the small amounts of additional magnification and demagnification). One suggested resolution to this problem is to include all the subhalos along the line of sight - Metcalf (2008) claimed this was the answer, and now Dan Dan Xu has tested this claim using the Millenium Simulation, and various assumptions for the satellite subhalo density profile.
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