These super-massive black holes at the center of galaxies are called active galactic nuclei. For the first time, the team observed a quasar with an active galactic nucleus, as part of the group of four, which is located more than a billion light years from Earth. The scientists used the two Keck telescopes on top of Mauna Kea in Hawaii. These are the largest optical/infrared telescopes in the world.
The team also used the United Kingdom Infrared Telescope (UKIRT) to follow up the Keck observations, to obtain current near-infrared images of the target galaxies.
"Astronomers have been trying to see directly what exactly is going on in the vicinity of these accreting super-massive black holes," said co-author Robert Antonucci, a UC Santa Barbara astrophysicist.
To observe such a distant object sharply enough in infrared wavelengths requires the use of a telescope having a diameter of about 100 meters or more. Instead of building such a large infrared telescope, which is currently impossible, a more practical way is to combine the beams from two or more telescopes that are roughly 100 meters apart. This method, used in radio astronomy for decades, is new for the infrared part of the spectrum. This type of instrument is called a long-baseline interferometer.
The Keck telescopes are separated by 85 meters and can be used as an interferometer. Combining the light from the telescopes allows astronomers to detect an interference pattern of the two beams and infer what the black hole vicinity looks like, explained first author Makoto Kishimoto, of the Max Planck Institute for Radio Astronomy in Bonn, Germany.
Kishimoto and Antonucci have a longstanding research collaboration, which began with Kishimoto's post-doctoral fellowship with Antonucci in the UCSB Department of Physics a decade ago. Antonucci points out that most of the credit for this current work goes to Kishimoto.
In 2003, astronomer Mark Swain at the Jet Propulsion Laboratory and his collaborators used the Keck Interferometer to observe the material accreting around one super-massive black hole, called NGC 4151. This is one of the brightest black holes in the optical and infrared wavelengths. The observations provided astronomers with the first direct clue about the inner region of a super-massive black hole system, said Antonucci.
"The results looked puzzling in 2003," said Kishimoto. "But with the new data and with more external information, we are quite sure of what we are seeing." According to the team's results, the Keck Interferometer has just begun to resolve the outer region of an active galactic nucleus's accreting gas, where co-existing dust grains are hot enough to evaporate, transitioning directly from a solid to a gas.
The W. M. Keck Observatory is a scientific partnership of the California Institute of Technology, the University of California, and NASA.
Gail Gallessich | EurekAlert!
Move over, lasers: Scientists can now create holograms from neutrons, too
21.10.2016 | National Institute of Standards and Technology (NIST)
Finding the lightest superdeformed triaxial atomic nucleus
20.10.2016 | The Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences
Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.
"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...
In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.
A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...
By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.
"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...
COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.
In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...
'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.
Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...
14.10.2016 | Event News
14.10.2016 | Event News
12.10.2016 | Event News
21.10.2016 | Health and Medicine
21.10.2016 | Information Technology
21.10.2016 | Materials Sciences