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Winds in ultraluminous X‐ray sources: New challenges
Astronomische Nachrichten, Volume 344, Issue 4, May 2023., 2023 Abstract Ultraluminous X‐ray sources (ULXs) are extreme X‐ray binaries shining above 1039 erg/s, in most cases as a consequence of super‐Eddington accretion onto neutron stars and stellar‐mass black holes accreting above their Eddington limit. This was understood after the discovery of coherent pulsations, cyclotron lines, and powerful winds.
C. Pinto, P. Kosec
wiley +1 more source
The Astrophysical Journal Letters, 2023 Pulsar timing array collaborations, such as the North American Nanohertz Observatory for Gravitational Waves (NANOGrav), are seeking to detect nanohertz gravitational waves emitted by supermassive black hole binaries formed in the aftermath of galaxy ...
Zaven Arzoumanian +78 more
doaj +1 more source
Black Hole Spin Properties of 130 AGN [PDF]
, 2013 Supermassive black holes may be described by their mass and spin. When supermassive black holes are active, the activity provides a probe of the state of the black hole system.
Daly, Ruth A., Sprinkle, Trevor B.
core +1 more source
Supermassive black holes in BCGs [PDF]
Proceedings of the International Astronomical Union, 2006 AbstractWe observed a sample of three Brightest Cluster Galaxies (BCGs), Abell 1836-BCG, Abell 2052-BCG, and Abell 3565-BCG, with the Advanced Camera for Surveys (ACS) and the Imaging Spectrograph (STIS) on board the Space Telescope. For each target galaxy we obtained high-resolution spectroscopy of the Hα and [N II] λ6583 emission lines at three slit ...
Bontá, E. D. +5 more
openaire +3 more sources
High-energy signatures of binary systems of supermassive black holes [PDF]
, 2016 Context. Binary systems of supermassive black holes are expected to be strong sources of long gravitational waves prior to merging. These systems are good candidates to be observed with forthcoming space-borne detectors.
Pérez, Daniela +2 more
core +3 more sources
Oscillating axion bubbles as alternative to supermassive black holes at galactic centers [PDF]
, 2006 Recent observations of near-infrared and X-ray flares from Sagittarius A*, which is believed to be a supermassive black hole at the Galactic center, show that the source exhibits about 20-minute periodic variability.
Anatoly A Svidzinsky +9 more
core +2 more sources
Growth of Supermassive Black Holes, Galaxy Mergers and Supermassive Binary Black Holes [PDF]
Proceedings of the International Astronomical Union, 2015 AbstractThe study of galaxy mergers and supermassive binary black holes (SMBBHs) is central to our understanding of the galaxy and black hole assembly and (co-)evolution at the epoch of structure formation and throughout cosmic history. Galaxy mergers are the sites of major accretion episodes, they power quasars, grow supermassive black holes (SMBHs ...
Komossa, S., Baker, J. G., Liu, F. K.
openaire +2 more sources
Extreme Mass Ratio Binary: Radiation reaction and gravitational waveform [PDF]
, 2005 For a successful detection of gravitational waves by LISA, it is essential to construct theoretical waveforms in a reliable manner. We discuss gravitational waves from an extreme mass ratio binary system which is expected to be a promising target of the ...
Barack L +8 more
core +2 more sources
Supermassive black hole demographics: evading M − σ [PDF]
Monthly Notices of the Royal Astronomical Society, 2019 We consider black hole - galaxy coevolution using simple analytic arguments. We focus on the fact that several supermassive black holes are known with masses significantly larger than suggested by the $M - $ relation, sometimes also with rather small stellar masses.
Andrew King, Rebecca Nealon
openaire +4 more sources
Key Science Goals for the Next-Generation Event Horizon Telescope
Galaxies, 2023 The Event Horizon Telescope (EHT) has led to the first images of a supermassive black hole, revealing the central compact objects in the elliptical galaxy M87 and the Milky Way.
Michael D. Johnson +44 more
doaj +1 more source