Search Publications

The nongravitational interactions of dark matter in colliding galaxy clusters

Massey, Richard; Harvey, David; Tittley, Eric +2 more

Collisions between galaxy clusters provide a test of the nongravitational forces acting on dark matter. Dark matter’s lack of deceleration in the “bullet cluster” collision constrained its self-interaction cross section σ_DM/m < 1.25 square centimeters per gram (cm²/g) [68% confidence limit (CL)] (σ_DM, self-inter…

Multiple images of a highly magnified supernova formed by an early-type cluster galaxy lens

Fontana, Adriano; Weiner, Benjamin J.; Schmidt, Kasper B. +28 more

In 1964, Refsdal hypothesized that a supernova whose light traversed multiple paths around a strong gravitational lens could be used to measure the rate of cosmic expansion. We report the discovery of such a system. In Hubble Space Telescope imaging, we have found four images of a single supernova forming an Einstein cross configuration around a r…

Evidence for mature bulges and an inside-out quenching phase 3 billion years after the Big Bang

Wuyts, S.; Förster Schreiber, N. M.; Genzel, R. +14 more

Most present-day galaxies with stellar masses ≥10¹¹ solar masses show no ongoing star formation and are dense spheroids. Ten billion years ago, similarly massive galaxies were typically forming stars at rates of hundreds solar masses per year. It is debated how star formation ceased, on which time scales, and how this “quenching” relate…

The bubble-like interior of the core-collapse supernova remnant Cassiopeia A

Milisavljevic, Dan; Fesen, Robert A.

The death of massive stars is believed to involve aspheric explosions initiated by the collapse of an iron core. The specifics of these catastrophic explosions remain uncertain, due partly to limited observational constraints on asymmetries deep inside the star. Here we present near-infrared observations of the young supernova remnant Cassiopeia A…