Source:   Brookhaven National Laboratory (http://www.bnl.gov/)


Date:   Posted 8/21/2000

Free Electron Laser Demonstrated At Brookhaven Lab

The first step in developing a leading-edge research tool that may open up
new fields of science
UPTON, NY -- Researchers from two U.S. Department of Energy laboratories --
Brookhaven National Laboratory and Argonne National Laboratory -- have taken
an important first step in creating a very powerful new tool to generate
extremely intense, coherent pulses of light.

Called the high gain harmonic generation free electron laser (HGHG FEL), this
leading-edge technology's unique capabilities will open up new research
opportunities in chemistry, biology and materials science. The work is
reported in the August 11 edition of the journal Science.

Light is one of the most important investigative tools for science. The
Brookhaven/Argonne team is developing a means to combine the advantages of
two very important light tools: lasers and accelerators.

Physicist Li Hua Yu, the principal investigator from Brookhaven on the
project, explained, "The HGHG FEL offers the possibility of combining the
intensity and coherence of a laser with the broad spectrum of light available
in a synchrotron, a type of accelerator. The invention of the laser provided
a revolutionary source of coherent light that created many new fields of
scientific research. The development of the HGHG FEL may extend the reach of
lasers to much shorter wavelengths, thus opening new research opportunities."

In a proof-of-principle experiment at Brookhaven's Accelerator Test Facility,
the researchers verified the theoretical foundation of the HGHG FEL operating
in the infrared region of the light spectrum. To extend its usefulness in a
wide range of scientific investigations, work is now focused on refining the
technique to produce pulses of shorter wavelength light in the deep
ultraviolet spectral region, with the ultimate goal of extending the approach
to generate coherent, high-intensity pulses of X-rays.

There is great interest around the world in producing coherent X-rays using
FEL techniques. The Brookhaven/Argonne team is unique in investigating the
HGHG approach, which will produce much sharper, short bursts of coherent
emissions.

An HGHG FEL would be a complementary research tool to Brookhaven's National
Synchrotron Light Source (NSLS), a facility used by approximately 2,500
researchers from around the world each year for a wide range of experiments.
The NSLS generates high-intensity light -- from infrared to ultraviolet and
X-rays -- for investigating materials as diverse as catalysts used in
refining petroleum, proteins important in drug design, microcircuits in
computers, and moon rocks.

Both the FEL and the NSLS are based on accelerator technology, but the light
pulses produced by a synchrotron are non-coherent, which means the electrons
that emit the light are unorganized, like musicians playing discordantly
while warming up before a concert. On the other hand, like musicians playing
together in a symphony following a conductor's lead, the HGHG FEL emits
coherent light, which makes the light more useful for experiments. This
coherent emission process facilitates the production of shorter and more
intense pulses of light than can be provided by a synchrotron. These intense
mini-pulses of light allow researchers to follow a time-dependent process,
such as a chemical reaction as it occurs in a tiny fraction of a second.

The success of the current HGHG FEL investigation provides a promising
roadmap towards using the technique with shorter wavelengths of light, which
will open up ever wider ranges of experiments. A deep ultraviolet FEL capable
of vacuum ultraviolet operation is now being assembled at Brookhaven. The
proof-of-principle experiments in the ultraviolet range are expected to take
place within two years, and, within the decade, the goal is to operate a HGHG
FEL in the X-ray range.





------------------------------------------------------------------------------
--

Note: This story has been adapted from a news release issued by Brookhaven
National Laboratory for journalists and other members of the public. If you
wish to quote from any part of this story, please credit Brookhaven National
Laboratory as the original source. You may also wish to include the following
link in any citation:

http://www.sciencedaily.com/releases/2000/08/000811065505.htm

<A HREF="http://www.ctrl.org/">www.ctrl.org</A>
DECLARATION & DISCLAIMER
==========
CTRL is a discussion & informational exchange list. Proselytizing propagandic
screeds are unwelcomed. Substance�not soap-boxing�please!  These are
sordid matters and 'conspiracy theory'�with its many half-truths, mis-
directions and outright frauds�is used politically by different groups with
major and minor effects spread throughout the spectrum of time and thought.
That being said, CTRLgives no endorsement to the validity of posts, and
always suggests to readers; be wary of what you read. CTRL gives no
credence to Holocaust denial and nazi's need not apply.

Let us please be civil and as always, Caveat Lector.
========================================================================
Archives Available at:
http://peach.ease.lsoft.com/archives/ctrl.html
 <A HREF="http://peach.ease.lsoft.com/archives/ctrl.html">Archives of
[EMAIL PROTECTED]</A>

http:[EMAIL PROTECTED]/
 <A HREF="http:[EMAIL PROTECTED]/">ctrl</A>
========================================================================
To subscribe to Conspiracy Theory Research List[CTRL] send email:
SUBSCRIBE CTRL [to:] [EMAIL PROTECTED]

To UNsubscribe to Conspiracy Theory Research List[CTRL] send email:
SIGNOFF CTRL [to:] [EMAIL PROTECTED]

Om

Reply via email to