Search Publications
A dynamic black hole corona in an active galaxy through X-ray reverberation mapping
Fabian, Andrew C.; Middleton, Matthew J.; Walton, Dominic J. +18 more
X-ray reverberation echoes are assumed to be produced in the strongly distorted spacetime around accreting supermassive black holes. This signal allows us to spatially map the geometry of the inner accretion flow1,2—a region that cannot yet be spatially resolved by any telescope—and provides a direct measure of the black hole mass and s…
Direct evidence for shock-powered optical emission in a nova
Wade, Gregg A.; Moffat, Anthony F. J.; Izzo, Luca +39 more
Classical novae are thermonuclear explosions that occur on the surfaces of white dwarf stars in interacting binary systems1. It has long been thought that the luminosity of classical novae is powered by continued nuclear burning on the surface of the white dwarf after the initial runaway2. However, recent observations of giga…
Resolving the Crab pulsar wind nebula at teraelectronvolt energies
H. E. S. S. Collaboration
The Crab nebula is one of the most-studied cosmic particle accelerators, shining brightly across the entire electromagnetic spectrum up to very-high-energy gamma rays1,2. It is known from observations in the radio to gamma-ray part of the spectrum that the nebula is powered by a pulsar, which converts most of its rotational energy losse…
Diffuse X-ray emission around an ultraluminous X-ray pulsar
Wolter, Anna; Pintore, Fabio; Mereghetti, Sandro +17 more
Ultraluminous X-ray sources (ULXs) are extragalactic X-ray emitters located off-centre of their host galaxy and with a luminosity in excess of a few 1039 erg s-1, if emitted isotropically1,2. The discovery of periodic modulation revealed that in some ULXs the accreting compact object is a neutron star3-7…
X-ray astronomy in 2019
Elvis, Martin
Every 10 years, X-ray astronomers gather in Bologna, Italy, to review the state of the field. After 30 years of these meetings, is there really still a separate field of X-ray astronomy?