Articles tagged with Accretion Discs
Researchers from USTC discovered the acceleration of quasar outflows at tens of parsecs, exceeding traditional accretion disk wind model predictions. The findings suggest a key role for interstellar dust in facilitating this acceleration.
A new simulation suggests that energy released near a black hole's event horizon during magnetic field line reconnection powers the intense flares. The process involves interactions between the magnetic field and material falling into the black hole, releasing hot plasma particles that radiate away as photons.
Researchers discovered that a large cavity in the discs surrounding evolved binary stars could be evidence of planet formation. The presence of heavy elements on the surface of dying stars suggests that dust particles rich in these elements were trapped by planets, supporting this hypothesis.
Researchers use ALMA and VLA to detect chaotic dust and gas streams caused by an intruder object interacting with the binary protostar. The study provides evidence of flyby events in nature, which can dramatically perturb circumstellar disks and impact planet formation.
A new study by Rice University astrophysicist André Izidoro suggests that the sun had rings before planets formed, explaining many solar system features. The model simulates the solar system's formation hundreds of times and reproduces several features missed by previous models, including pressure bumps and rings.
Researchers at the DOE's Princeton Plasma Physics Laboratory discovered a process in plasma swirling around black holes that causes previously unexplained emissions of light and heat. The process, known as magnetic reconnection, also jettisons huge plumes of plasma billions of miles in length.
Researchers used computer simulations to investigate the conversion rates of neutrons and protons in accretion disks surrounding black holes, finding that disks with masses between 0.01 to 0.1 solar masses are optimal for heavy element production. This suggests that neutron star mergers producing such disks could be the origin of a lar...
Theoretical physicists modelled the region around M87's supermassive black hole, confirming that gravity plays a key role in accelerating particles out to thousands of light years. The findings provide further evidence for Einstein's theory of general relativity and its application to astrophysical phenomena.
The study reveals that supermassive black holes exhibit accretion states similar to those seen in stellar mass black holes, with properties including thermal emission by the plasma disc and intense radio emission. This new understanding helps clarify the activity cycles of supermassive black holes in galaxy centers.
A new NASA visualization reveals the hypnotic pas de deux of two orbiting black holes, distorting and redirecting light from their accretion disks. The system's unique features, including relativistic aberration and Doppler boosting, create striking images of each black hole.
A new model integrates two phases of matter accumulation in active galaxies, revealing a universal mechanism for ejection of matter by black holes. The research suggests that the molecular phase is part of the outflow, blowing away more matter than previously thought.
Astronomers have provided clear evidence for the formation of an accretion disk around a supermassive black hole during a tidal disruption event. The new findings support theoretical predictions and provide unprecedented insights into these unusual events.
Scientists have detected a mysterious gamma-ray heartbeat from a cosmic gas cloud in the constellation Aquila, powered by a neighbouring precessing black hole. The research team analysed over ten years of data from NASA's Fermi gamma-ray space telescope, revealing a consistent period between the cloud's emission and the black hole's jets.
Astronomers have detected a supermassive black hole's heartbeat, which has been ongoing for over ten years. The signal was spotted again in 2018 using X-ray satellite observations, providing valuable information about the black hole's event horizon.
Astronomers have observed a confirmed heartbeat in a supermassive black hole for over ten years, with the signal repeating every hour. The research provides new insights into the black hole's size and structure close to its event horizon.
Researchers observed an accreting neutron star entering an outburst phase, studying its structure and material movement. The observation revealed a 12-day process, contradicting previous theories of two- to three-day timescales.
Astronomers using ALMA have spotted quasi-periodic flickers in millimeter-waves from the center of the Milky Way, suggesting a rotating radio spot circling a supermassive black hole. The findings provide insight into space-time with extreme gravity and may shed light on the behavior of gas around the black hole.
Researchers combined data from radio and optical telescopes to determine the origins and nature of quasar light. By measuring the polarization, they can tell which part of radiation came from the jet and determine its direction.
Researchers propose a new theory on how massive, spinning black holes form near supermassive black holes at the centers of active galactic nuclei. This 'Pac-Man-like' behavior offers a natural explanation for high-mass binary black hole mergers and could help understand galaxy growth.
NICER detected a record-breaking X-ray burst from pulsar SAX J1808.4-3658, revealing a two-step change in brightness caused by the ejection of separate layers from the pulsar surface. The observations also show X-rays reflecting off of the accretion disk and burst oscillations.
Astronomers using ALMA have imaged a cosmic pretzel, a network of gas and dust surrounding two young binary stars. The structure is similar to the asteroid belt in our Solar System, with spiral shapes displaying complex dynamics.
A team of researchers has observed the rapid fuel consumption of eight quasars, revealing the role of strong gravity in feeding massive black holes. The study's findings provide new insights into the behavior of supermassive black holes at the center of quasars.
Researchers used reverberation mapping to determine the mass of NGC 4395's black hole, finding it to be about 10,000 times the mass of our sun. This is the smallest black hole found via this technique and provides new insights into dwarf galaxies and their nuclear black holes.
Researchers create most detailed simulation of black hole, proving theoretical predictions about accretion disks. The inner-most region of an accretion disk aligns with its black hole's equator, solving a longstanding mystery from 1975.
Astronomers have discovered rapidly swinging jets from a black hole in V404 Cygni, behaving in a way never seen before. The jets are thought to be caused by the misalignment of the accretion disk and the black hole, resulting in a wobble-like motion.
The first real image of a black hole, obtained by EHT telescopes, confirms the predictions made in Jean-Pierre Luminet's 1979 simulation. The image shows an extraordinary accuracy, with characteristics such as the Einstein effect and Doppler shift clearly visible.
A novel experiment at PPPL has demonstrated the validity of magnetorotational instability (MRI) theory, which explains how stars and planets form from accretion disks. The study found that weakly tethered rotating balls gained angular momentum and shifted outward, consistent with MRI predictions.
Researchers have charted the environment surrounding a stellar-mass black hole using NASA's NICER payload. The study reveals changes in the environment's size and shape, including the corona contracting vertically from 100 to 10 miles at vast distances.
Researchers detected 'echoes' within an X-ray burst from a black hole, suggesting the corona shrinks as it feeds. The corona, halo of highly-energized electrons, significantly contracts from 100km to 10km in just over a month.
Researchers used NASA's NICER payload to detect X-ray light from a small black hole (J1820) consuming material from a companion star. Light echoes revealed changes in the environment's size and shape, providing new insights into stellar-mass black holes' behavior.
Researchers used a rotating water-filled device to simulate the magnetorotational instability, which helps explain how matter falls inward to form planets in a reasonable time. The experiment confirmed the strong impact of magnetic forces on metal behavior, paving the way for a clearer understanding of accretion disk dynamics.
Astronomers detected a fast-moving jet from a neutron star with a strong magnetic field, challenging the long-held idea that magnetic fields prevent jets from forming. The discovery was made using the VLA, which revealed radio waves produced by the jet, characteristic of other jet-producing systems.
Statistical analysis suggests that supermassive black hole spin plays a role in generating high-speed jets and powerful radio waves. Nearly 8000 quasars were analyzed, with O III oxygen emissions found to be stronger in radio loud quasars, implying spin's importance.
Astronomers measured the magnetic field of a black hole in a binary system using data from a sudden flare. The field was found to be substantially weaker than expected, providing new insights into how black holes consume material.
Researchers at Sandia National Laboratories have challenged long-standing theories on black holes using hands-on experiments at the Z machine. The study found that certain ionization stages of iron are not present in a black hole's accretion disk, contradicting previous assumptions.
Astronomers study properties of debris disk around sun-like star by analyzing light passing through it. The transit allows scientists to infer characteristics of the disk and potentially discover analogues in our Solar System.
Scientists develop rigorous new method for modeling the accretion disk that feeds the supermassive black hole at the center of the Milky Way galaxy. This approach replaces traditional formulas with a kinetic method to trace collisionless particles, improving understanding of plasma behavior and radiative efficiency.
Researchers modeled massive star formation using high-performance computers, discovering episodic luminosity bursts that outshine the collective effect of 100,000 Suns. These bursts are thought to be caused by the migration of dense clumps through accretion disks, offering new insights into the birth process of massive stars.
A team of OU researchers collaborated with citizen scientists to discover a rare circumstellar disk, the oldest of its kind, around a red dwarf star. The discovery provides insights into why M dwarf disks appear so rare and may hold clues about the possibility of extrasolar planets.
A team of citizen scientists and professional astronomers have discovered an unusual exoplanet hunting ground, finding the oldest known circumstellar disk orbiting a young star. The discovery, led by Steven Silverberg, reveals a red dwarf star with a warm disk that has sustained its disk for an exceptionally long time.
Astronomers have detected superhot blobs of gas being ejected near the dying star V Hydrae, with each blob twice as massive as Mars and traveling at half-million miles per hour. The plasma balls are thought to be launched by an unseen companion star in an elliptical orbit, shedding new light on planetary nebulae.
The TW Hydrae system shows a prominent gap that is unlikely to be caused by an actively accreting protoplanet. Instead, researchers attribute the feature to photoevaporation, which heats gas and allows it to fly away from the disk. This process may disperse the disk before planets can form.
Astronomers from UMD and Michigan document X-rays bouncing off inner accretion disk near dormant black hole Swift J1644+57. The study reveals the shape and activity of the accretion disk, opening a door to reliable measurements of black hole spin.
New computer simulations from Georgia Tech investigate the possibility that red giant stars were dimmed after collisions with a gaseous accretion disk at the galactic center. The simulations suggest that these collisions could have caused significant damage to the red giant stars, stripping away mass and lowering their kinetic energy.
Researchers at the IAC discovered a powerful wind of neutral material in the outer layers of V404 Cygni's accretion disc. This wind regulates accretion, causing shorter outbursts, and has been detected for the first time in a black hole system.
A team of astrophysicists has detected an intense wind in the neighborhood of a black hole, which is formed in the outer layers of the accretion disc. The wind has a high velocity of 3,000 km/s and plays a crucial role in regulating the accretion of material by the black hole.
Researchers discovered that stars undergo sharp stellar brightening caused by gravitational instabilities in massive gaseous disks, leading to a new understanding of star formation and evolution. The discovery may imply that our Sun experienced several such episodes, affecting the formation of giant planets.
Astronomers suggest that large spiral patterns in circumstellar disks around young stars may indicate the presence of giant unseen planets. Computer simulations support this idea by showing how gas-and-dust disks evolve and how planets can modify disk structures, revealing their mass and position.
Astronomers have discovered unexplained wave-like structures in the dusty disk surrounding the young star AU Mic, moving at speeds of up to 22,000 miles per hour. The features, resembling ripples in water, are unlike anything ever observed or predicted and may provide valuable clues about planet formation.
Astronomers have found evidence that two classes of blazars represent different sides of the same cosmic coin, with one class being a gas-guzzling car and the other an energy-efficient electric vehicle. The team's redshift survey revealed that FSRQs began to decline while BL Lacs increased in numbers around 5.6 billion years ago.
Astronomers at Durham University developed a new way to measure supermassive black holes' spin, which is linked to their role in driving galaxy growth. The technique uses the distance between a black hole and its feeding disc to estimate spin.
Recent supercomputer simulations on XSEDE provide new insights into the interaction between jets, accretion disks, and magnetic fields around black holes. The findings challenge the long-held simplistic view of these phenomena, revealing a more complex and dynamic relationship between the jet, disk, and gravitational forces.
Astronomers have measured the closest distance that matter can approach a black hole without being pulled in. The findings suggest that the accretion disk is spinning in the same direction as the black hole, providing new insights into gravity and space.
Astronomers use XMM-Newton data to detect X-ray 'echoes' from a distant galaxy, revealing a new way to study supersized black holes and their accretion disks. The echoes, which lag behind AGN flares by up to 30 minutes, provide insights into the environment around these massive black holes.
An international team of astronomers identified the moment when a black hole launched super-fast knots of gas into space using NASA's RXTE and NSF's VLBA radio telescope. The 'bullets' of ionized gas were thought to arise from a region outside the event horizon, where they were associated with changes signaling the start of the process.
A gamma-ray flash was detected coming from a distant galaxy, suggesting a massive black hole is consuming a star. The long-duration event produced an enormous amount of energy and appears to be emanating from the center of the galaxy.
Researchers analyzed X-ray data from space telescopes to understand the relationship between a black hole's accretion rate and ionization state of its surrounding disk. The study found a linear dependence on the rate of accretion, contradicting theoretical predictions.
A study by researchers at The University of Nottingham reveals the devastating impact of supermassive black holes on galaxies. These behemoths strip massive galaxies of cool gases required for new stars, causing ageing red giants to dwindle in existence.
Astronomers study the galaxy's most active black-hole binary, revealing a dramatic change in the accretion disk's behavior. The Suzaku observations show that at low brightness, the inner edge of the disk retreats up to 600 miles from the black hole.
Astronomers have discovered a unique double-star system that represents a 'missing link' stage in the birth process of millisecond pulsars. The system, J1023, shows evidence for an accretion disk surrounding the neutron star before it disappeared and the pulsar emerged.