Search Publications
The Large, Oxygen-Rich Halos of Star-Forming Galaxies Are a Major Reservoir of Galactic Metals
Sembach, K. R.; Davé, R.; Prochaska, J. X. +11 more
The circumgalactic medium (CGM) is fed by galaxy outflows and accretion of intergalactic gas, but its mass, heavy element enrichment, and relation to galaxy properties are poorly constrained by observations. In a survey of the outskirts of 42 galaxies with the Cosmic Origins Spectrograph onboard the Hubble Space Telescope, we detected ubiquitous, …
An Extremely Luminous Panchromatic Outburst from the Nucleus of a Distant Galaxy
Cenko, S. B.; Sánchez-Ramírez, R.; Cooper, M. C. +60 more
Variable x-ray and γ-ray emission is characteristic of the most extreme physical processes in the universe. We present multiwavelength observations of a unique γ-ray-selected transient detected by the Swift satellite, accompanied by bright emission across the electromagnetic spectrum, and whose properties are unlike any previously observed source.…
Discovery of Powerful Gamma-Ray Flares from the Crab Nebula
Bignami, G. F.; Costa, E.; Mereghetti, S. +65 more
The well-known Crab Nebula is at the center of the SN1054 supernova remnant. It consists of a rotationally powered pulsar interacting with a surrounding nebula through a relativistic particle wind. The emissions originating from the pulsar and nebula have been considered to be essentially stable. Here, we report the detection of strong gamma-ray (…
The Hidden Mass and Large Spatial Extent of a Post-Starburst Galaxy Outflow
Bowen, David V.; Tripp, Todd M.; Jenkins, Edward B. +9 more
Outflowing winds of multiphase plasma have been proposed to regulate the buildup of galaxies, but key aspects of these outflows have not been probed with observations. By using ultraviolet absorption spectroscopy, we show that “warm-hot” plasma at 105.5 kelvin contains 10 to 150 times more mass than the cold gas in a post-starburst gala…
A Reservoir of Ionized Gas in the Galactic Halo to Sustain Star Formation in the Milky Way
Lehner, Nicolas; Howk, J. Christopher
Without a source of new gas, our Galaxy would exhaust its supply of gas through the formation of stars. Ionized gas clouds observed at high velocity may be a reservoir of such gas, but their distances are key for placing them in the galactic halo and unraveling their role. We have used the Hubble Space Telescope to blindly search for ionized high-…