Search Publications
Birth of a relativistic outflow in the unusual γ-ray transient Swift J164449.3+573451
Berger, E.; Frail, D. A.; Kulkarni, S. R. +24 more
Active galactic nuclei, which are powered by long-term accretion onto central supermassive black holes, produce relativistic jets with lifetimes of at least one million years, and the observation of the birth of such a jet is therefore unlikely. Transient accretion onto a supermassive black hole, for example through the tidal disruption of a stray…
Exclusion of a luminous red giant as a companion star to the progenitor of supernova SN 2011fe
Kulkarni, S. R.; Filippenko, Alexei V.; Cenko, S. Bradley +26 more
Type Ia supernovae are thought to result from a thermonuclear explosion of an accreting white dwarf in a binary system, but little is known of the precise nature of the companion star and the physical properties of the progenitor system. There are two classes of models: double-degenerate (involving two white dwarfs in a close binary system) and si…
A candidate redshift z~10 galaxy and rapid changes in that population at an age of 500Myr
Trenti, M.; Oesch, P. A.; Carollo, C. M. +9 more
Searches for very-high-redshift galaxies over the past decade have yielded a large sample of more than 6,000 galaxies existing just 900-2,000million years (Myr) after the Big Bang (redshifts 6>z>3 ref. 1). The Hubble Ultra Deep Field (HUDF09) data have yielded the first reliable detections of z~8 galaxies that, together with reports of a γ-r…
An actively accreting massive black hole in the dwarf starburst galaxy Henize2-10
Johnson, Kelsey E.; Reines, Amy E.; Sivakoff, Gregory R. +1 more
Supermassive black holes are now thought to lie at the heart of every giant galaxy with a spheroidal component, including our own Milky Way. The birth and growth of the first `seed' black holes in the earlier Universe, however, is observationally unconstrained and we are only beginning to piece together a scenario for their subsequent evolution. H…
The unusual γ-ray burst GRB 101225A from a helium star/neutron star merger at redshift 0.33
Im, M.; Fryer, C. L.; Choi, C. +31 more
Long γ-ray bursts (GRBs) are the most dramatic examples of massive stellar deaths, often associated with supernovae. They release ultra-relativistic jets, which produce non-thermal emission through synchrotron radiation as they interact with the surrounding medium. Here we report observations of the unusual GRB 101225A. Its γ-ray emission was exce…
Supermassive black holes do not correlate with dark matter haloes of galaxies
Kormendy, John; Bender, Ralf
Supermassive black holes have been detected in all galaxies that contain bulge components when the galaxies observed were close enough that the searches were feasible. Together with the observation that bigger black holes live in bigger bulges, this has led to the belief that black-hole growth and bulge formation regulate each other. That is, blac…
A close nuclear black-hole pair in the spiral galaxy NGC3393
Elvis, M.; Fabbiano, G.; Wang, Junfeng +1 more
The current picture of galaxy evolution advocates co-evolution of galaxies and their nuclear massive black holes, through accretion and galactic merging. Pairs of quasars, each with a massive black hole at the centre of its galaxy, have separations of 6,000 to 300,000 light years (refs 2 and 3; 1parsec = 3.26light years) and exemplify the first st…
X-ray illumination of the ejecta of supernova 1987A
Panagia, N.; Larsson, J.; Sollerman, J. +25 more
When a massive star explodes as a supernova, substantial amounts of radioactive elements--primarily 56Ni, 57Ni and 44Ti--are produced. After the initial flash of light from shock heating, the fading light emitted by the supernova is due to the decay of these elements. However, after decades, the energy powering a s…
Black hole growth in the early Universe is self-regulated and largely hidden from view
Schawinski, Kevin; Gawiser, Eric; Volonteri, Marta +2 more
The formation of the first massive objects in the infant Universe remains impossible to observe directly and yet it sets the stage for the subsequent evolution of galaxies. Although some black holes with masses more than 109 times that of the Sun have been detected in luminous quasars less than one billion years after the Big Bang, thes…
A distortion of very-high-redshift galaxy number counts by gravitational lensing
Yan, Haojing; Windhorst, Rogier A.; Mao, Shude +1 more
The observed number counts of high-redshift galaxy candidates have been used to build up a statistical description of star-forming activity at redshift z>~7, when galaxies reionized the Universe. Standard models predict that a high incidence of gravitational lensing will probably distort measurements of flux and number of these earliest galaxie…