Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Evidence for Ultra-Energetic Particles in Jet from Black Hole

21.06.2006
An international team of astronomers, led by Dr Sebastian Jester from the University of Southampton, has obtained key X-ray observations that reveal the nature of quasar particle jets which originate just outside super-massive black holes at the centre of galaxies and radiate across the spectrum from radio to X-ray wavelengths. A complementary study of jet infrared emission, led by astronomers at Yale University, reaches the same conclusion.

Both studies involve the jet of the quasar 3C273, famous since its identification in 1963 as the first quasar. It now appears that the most energetic radiation from this jet arises through direct radiation from extremely energetic particles, and not in the way expected by most astronomers based on the previously available data. The two reports, available now online in the Astrophysical Journal, will appear in print in the September 10 issue.

"Quasar jets attain nearly the speed of light and emit infrared-visible light and X-rays. But the jets have been too distant and faint to collect sufficient data to decide the nature of the emission until now," said Sebastian Jester, working at the University of Southampton with funding from an Otto Hahn fellowship from Germany's Max Planck Society, the leader of one study and a co-author on the other. "These data are a significant advance in what we know about jets, and the results clearly suggest ultra-energetic particles are emitting synchrotron radiation in 3C273."

There have been two competing theories of how X-ray emission arises from the particles - the "Inverse-Compton" theory proposing that the emissions occur when jet particles scatter cosmic microwave background photons, and the "Synchrotron Radiation" theory postulating a separate population of extremely energetic electrons or protons that cause the high-energy emission.

Dr Jester led a team of collaborators at MIT and the Smithsonian Astrophysical Observatory (SAO) in Cambridge, MA, and at the Max Planck Institute for Astronomy in Heidelberg, to observe the 3C273 jet with the Chandra X-ray Observatory. Their more detailed Chandra data allowed the first in-depth study of the energy distribution of the X-rays from the jet, which supported the synchrotron theory.

In a complementary study, a team led by Dr Yasunobu Uchiyama, former postdoctoral fellow at the Yale Center for Astronomy, observed the 3C273 jet with the Spitzer Space Telescope, "because it is located in space and is more sensitive to faint infrared jet emission than any previous telescope," said Uchiyama. Spitzer observations enabled the team, with collaborators at Stanford, the University of Southampton, Goddard Space Flight Center, and the Brera Observatory in Milan, to determine the infrared spectrum for the first time and thus to deduce the origin of the radio through X-ray emission.

Both teams also used data from the third of NASA's Great Observatories, the Hubble Space Telescope, and the radio telescopes of the Very Large Array (VLA). The three space telescopes and the VLA "see" emission of different wavelengths from celestial objects, and the combination is essential to reveal a new comprehensive perspective on the jets.

"The new multiwavelength data clearly show the emission at radio, infrared, optical and X-ray wavelengths is linked," said C. Megan Urry, Israel Munson Professor of Physics and Astronomy at Yale, and an author on the Uchiyama study. "This strongly suggests that ultra-energetic particles in the 3C273 jet are producing all their light via synchrotron radiation."

According to the researchers, while the lifetime of the X-ray producing particles is only about 100 years, the data indicate that the visibly brightest part of the jet has a length of about 100,000 light years. Since there would be insufficient time for the particles to shoot out from the black hole at close to the speed of light and then release their energy as radiation as far out as they are seen, the particles have to be accelerated locally, where they produce their emission.

"Our results call for a radical rethink of the physics of relativistic jets that black holes drive," said Uchiyama. "But we now have a crucial new clue to solving one of the major mysteries in high-energy astrophysics." Sebastian Jester adds: "The new observations show that the flow structure of this jet is more complicated than had been assumed previously. That the present evidence favors the synchrotron model deepens the mystery of how jets produce the ultra-energetic particles that radiate at X-ray wavelengths. Fermilab, CERN and DESY would be jealous!"

Other authors on the Uchiyama paper include Jeffrey Van Duyne and Paolo Coppi from Yale; C.C. Cheung, Stanford University; Rita Sambruna, NASA/GSFC, Greenbelt, MD; Tadayuki Takahashi, ISAS/JAXA, Japan; and Laura Maraschi and Fabrizio Tavecchio, Osservatorio Astronomico di Brera, Milan. Other authors on the Jester paper include Dan Harris from the Smithsonian Astrophysical Observatory (SAO), Herman Marshall from the MIT Kavli Institute for Astrophysics and Space Research; and Klaus Meisenheimer, Max Planck Institute for Astronomy in Heidelberg. Grant and contract funding from NASA supported the research.

Sarah Watts | alfa

More articles from Physics and Astronomy:

nachricht Engineering team images tiny quasicrystals as they form
18.08.2017 | Cornell University

nachricht Astrophysicists explain the mysterious behavior of cosmic rays
18.08.2017 | Moscow Institute of Physics and Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

A Map of the Cell’s Power Station

18.08.2017 | Life Sciences

Engineering team images tiny quasicrystals as they form

18.08.2017 | Physics and Astronomy

Researchers printed graphene-like materials with inkjet

18.08.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>