Double or Nothing: Astronomers Rethink Quasar Environment
March 12, 2018
Using Hyper Suprime-Cam mounted on the Subaru Telescope, astronomers have identified nearly 200 protoclusters, the progenitors of galaxy clusters, in the early Universe, about 12 billion years ago, about ten times more than previously known. They also found that quasars don't tend to reside in protoclusters; but if there is one quasar in a protocluster, there is likely a second nearby. This result raises doubts about the relation between protoclusters and quasars...
Unprecedentedly Wide and Sharp Dark Matter Map
March 1, 2018
A research team of researchers released an unprecedentedly wide and sharp dark matter map based on the newly obtained imaging data by Hyper Suprime-Cam on the Subaru Telescope. The dark matter distribution is estimated by the weak gravitational lensing technique. The team located the positions and lensing signals of the dark matter halos and found indications that the number of halos could be inconsistent with what the simplest cosmological model suggests...