Astrophysics

The magnetospheres and jets of black holes host collisionless and highly magnetized plasmas. In such plasmas, relativistic magnetic reconnection may catalyze the release of free magnetic energy, powering quiescent and – especially – flaring emission...

The Atacama Cosmology Telescope is a ground-based CMB survey that has mapped half the millimeter sky at significantly higher resolution and sensitivity than the Planck satellite. I will present new ACT results from a 9400 sq.deg. gravitational...

Driven by gravity, galaxies continuously grow through accretion of smaller systems. Stellar streams are nice illustrations of this hierarchical build-up, but the accreted stars quickly disperse. I will present advanced dynamical models that can...

Abstract: The Atacama Cosmology Telescope is a ground-based CMB survey that has mapped half the millimeter sky at significantly higher resolution and sensitivity than the Planck satellite. I will present new ACT results from a 9400 sq.deg...

The Bahcall Lunch follows the astrophysics colloquium lecture. 

The birth of stars is one of the most complex problems challenging modern astrophysics. Understanding their origins is of fundamental importance to many areas of astronomy, from exoplanet studies to cosmology. While the study of the initial...

While models of dark energy can be tuned to match the observed late-time accelerated expansion of the universe, similar to a cosmological constant, they at the same time also change the relationship between the gravitational potentials. The E_G...

The very first step in planet formation is to build planetesimals out of dust particles in protoplanetary disks. The origin and demographics of planetesimals are crucial to understanding the Solar System, exoplanetary systems, and circumstellar...