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Scientists discover vast intergalactic cloud of plasma
05/07/2007
From Spaceflightnow.com
Los Alamos National Laboratory News Release
(Additional comments below)
LOS ALAMOS, New Mexico - Combining the
world's largest radio telescope at Arecibo, Puerto Rico with a
precision imaging, seven-antenna synthesis radio telescope at the
Dominion Radio Astrophysical Observatory (DRAO), a team of
researchers led by Los Alamos scientist Philipp Kronberg have
discovered a new giant in the heavens, a giant in the form of a
previously undetected cloud of intergalactic plasma that stretches
more than 6 million light years across. The diffuse, magnetized
intergalactic zone of high energy electrons may be evidence for
galaxy-sized black holes as sources for the mysterious cosmic rays
that continuously zip though the Universe.
In research reported in the April issue of Astrophysical Journal,
the team of researchers from Los Alamos, Arecibo, and DRAO in
Penticton, British Columbia describe their discovery of a 2-3
megaparsec zone of diffuse, intergalactic plasma located beside the
Coma cluster of galaxies. The combined use of the 305 meter Arecibo
radio telescope to make a base scan of 50 square degrees of sky, and
the DRAO, making 24 separate 12 hour observations over 24 days of
the same sky area, resulted in an image comparable to that of a 1000
meter diameter radio telescope. After Arecibo mapped the larger
cloud structure, DRAO data was used to enhance the resolution of the
image.
According to Kronberg, "One of the most exciting aspects of the
discovery is the new questions it poses. For example, what kind of
mechanism could create a cloud of such enormous dimensions that does
not coincide with any single galaxy, or galaxy cluster? Is that same
mechanism connected to the mysterious source of the ultra high
energy cosmic rays that come from beyond our galaxy? And separately,
could the newly discovered fluctuating radio glow be related to
unwanted foregrounds of the Cosmic Microwave Background (CMB)
radiation?"
The synchrotron-radiating plasma cloud is spread across a vast
region of space that may contain several black hole harboring radio
galaxies. The cloud may be evidence that black holes in galaxies
convert and transfer their enormous gravitational energy, by a yet
unknown process, into magnetic fields and cosmic rays in the vast
intergalactic regions of the Universe.
Kronberg's work also provides the first preview of small (arc minute
- level) features that could be associated with unwanted and
confusing foregrounds to the CMB radiation. Because these same
radiation frequencies are to be imaged by the PLANCK CMB Explorer,
corrections to the observed CMB for foreground fluctuations (the
so-called microwave "cirrus clouds") are vitally important to using
CMB fluctuations as a probe of the early Universe.
In addition to Kronberg, other members of the research team
included, Roland Kothes from DRAO, and Christopher Salter and Phil
Perillat from Arecibo and the National Astronomy and Ionosphere
Center. The DRAO is operated by the Herzberg Institute of
Astrophysics and the National Research Council of Canada.
Los Alamos National Laboratory, a multidisciplinary research
institution engaged in strategic science on behalf of national
security, is operated by Los Alamos National Security, LLC, a team
composed of Bechtel National, the University of California, BWX
Technologies, and Washington Group International for the Department
of Energy's National Nuclear Security Administration.
Los Alamos enhances national security by ensuring the safety and
reliability of the U.S. nuclear stockpile, developing technologies
to reduce threats from weapons of mass destruction, and solving
problems related to energy, environment, infrastructure, health, and
global security concerns.
Full story
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