Featured Research

from universities, journals, and other organizations

Evidence For Ultra-energetic Particles In Jet From Black Hole

Date:
June 21, 2006
Source:
Yale University
Summary:
An international team of astronomers led by researchers at Yale has obtained key infrared observations that reveal the nature of quasar particle jets that originate just outside super-massive black holes at the center of galaxies and radiate across the spectrum from radio to X-ray wavelengths; a complementary study of jet X-ray emission led by astronomers at the University of Southampton, reaches the same conclusion.

False-colour composite showing the relation between the quasar 3C273 (top left; the quasar is really just a very small and bright source, the fuzz apparently surrounding it is an artifact that appears when taking a picture of a very bright source with a camera and telescope for very faint things) and the jet.
Credit: Image S. Jester, D.E. Harris, H.L. Marshall, K. Meisenheimer, H.-J. Rφser, and R. Perley

An international team of astronomers led by researchers at Yale has obtained key infrared observations that reveal the nature of quasar particle jets that originate just outside super-massive black holes at the center of galaxies and radiate across the spectrum from radio to X-ray wavelengths; a complementary study of jet X-ray emission led by astronomers at the University of Southampton, 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, although extremely luminous, are so distant as to be relatively faint and difficult to observe. Thanks to the sensitivity of NASA's Great Observatories, we have been able to map the 3C273 jet in infrared, visible light and X-rays," said C. Megan Urry, Israel Munson Professor of Physics and Astronomy at Yale, and an author on one study. "These combined data strongly suggest that ultra-energetic particles in the 3C273 jet are producing their light via synchrotron radiation."

There have been two competing theories of how emissions arise 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.

"The Yale team used the Spitzer Space Telescope to observe 3C273 because it is located in space and is more sensitive to faint infrared jet emission than any previous telescope," said Yasunobu Uchiyama, a team leader and former postdoctoral fellow at the Yale Center for Astronomy. Spitzer observations enabled the team, with collaborators at Stanford, 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 realize its close connection to the X-ray emission.

Sebastian Jester, now at the University of Southampton, led a complementary study that used the Chandra X-ray Observatory. This team, with collaborators at MIT Kavli Institute for Astrophysics and Space Research and the Smithsonian Astrophysical Observatory (SAO) in Cambridge, MA, and at the Max Planck Institute for Astronomy in Heidelberg, obtained the first detailed study of energy distribution of X-rays from the jet, which also supported the synchrotron theory.

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.

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 combined data was essential to reveal the new comprehensive perspective on the jets.

"The new observations show that the flow structure of this jet is more complicated than had been assumed previously," Jester explains. "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."

"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."

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


Story Source:

The above story is based on materials provided by Yale University. Note: Materials may be edited for content and length.


Cite This Page:

Yale University. "Evidence For Ultra-energetic Particles In Jet From Black Hole." ScienceDaily. ScienceDaily, 21 June 2006. <www.sciencedaily.com/releases/2006/06/060621083047.htm>.
Yale University. (2006, June 21). Evidence For Ultra-energetic Particles In Jet From Black Hole. ScienceDaily. Retrieved August 27, 2014 from www.sciencedaily.com/releases/2006/06/060621083047.htm
Yale University. "Evidence For Ultra-energetic Particles In Jet From Black Hole." ScienceDaily. www.sciencedaily.com/releases/2006/06/060621083047.htm (accessed August 27, 2014).

Share This




More Space & Time News

Wednesday, August 27, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

SpaceX’s Falcon 9 Rocket Explodes After Liftoff

SpaceX’s Falcon 9 Rocket Explodes After Liftoff

Newsy (Aug. 23, 2014) — The private spaceflight company says it is preparing a thorough investigation into Friday's mishap. Video provided by Newsy
Powered by NewsLook.com
Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Did Russia Really Find Plankton On The ISS? NASA Not So Sure

Newsy (Aug. 21, 2014) — Russian cosmonauts say they've found evidence of sea plankton on the International Space Station's windows. NASA is a little more skeptical. Video provided by Newsy
Powered by NewsLook.com
Space to Ground: Hello Georges

Space to Ground: Hello Georges

NASA (Aug. 18, 2014) — Europe's ATV-5 delivers new science and the crew tests smart SPHERES. Questions or comments? Use #spacetoground to talk to us. Video provided by NASA
Powered by NewsLook.com
Tiny Satellites, Like The One Tossed From ISS, On The Rise

Tiny Satellites, Like The One Tossed From ISS, On The Rise

Newsy (Aug. 18, 2014) — The Chasqui I, hand-delivered into orbit by a Russian cosmonaut, is one of hundreds of small satellites set to go up in the next few years. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



    Save/Print:
    Share:  

    Free Subscriptions


    Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

    Get Social & Mobile


    Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

    Have Feedback?


    Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
    Mobile iPhone Android Web
    Follow Facebook Twitter Google+
    Subscribe RSS Feeds Email Newsletters
    Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins