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The Pentagon's pursuit of a new kind of nonnuclear super-weapon has sparked a behind-the-scenes revolt among its elite scientific advisers, some of whom reject the scheme as pseudoscience. The military's goal is to develop a bomb that might be far more powerful
than existing conventional weapons of the same size. Precisely targeted, such
a weapon could take out targets -- such as underground caverns that conceal
weapons of mass destruction -- without posing the severe political risks of
using nuclear bombs.
The key to the concept is a little known element called hafnium. By
figuring out how to unleash the abundant energy from a hafnium isotope, called
hafnium-178, the military hopes to develop a new generation of weapons.
According to a Defense Department Web site, such a weapon might "revolutionize
all aspects of warfare."
The Pentagon is now quietly investigating ways to mass produce the isotope.
Late last year, it created the 12-member Hafnium Isomer Production Panel
(HIPP). Its purpose: to assess ways to mass-produce the isotope for military
uses ranging from bombs to advanced forms of propulsion.
Yet some of the nation's most distinguished scientists and military advisers say that such futuristic dreams of tomorrow's battlefields are premature at best and nonsense at worst. For four years, working largely behind the scenes, they have advised the Pentagon that claims by hafnium-178 enthusiasts -- led by physicist Carl Collins of the University of Texas -- defy sound physical theory and have not been reproduced in lab experiments by other researchers. For the first time, some of these skeptics are going public with their concerns. Last month, in a memorandum to Pentagon and Energy Department officials obtained by The Chronicle, five of the 12 members of the military's own advisory panel on mass producing hafnium-178 and other top experts warned against prematurely proceeding to develop weapons "applications that may not make physical sense." "In my opinion, this matter is worse than cold fusion," said panel member Bill Herrmannsfeldt, referring to unconfirmed claims by scientists in the 1980s that they had generated nuclear fusion energy at low temperatures. Herrmannsfeldt, a physicist at the Stanford Linear Accelerator Center, is leading a revolt against hafnium-178 weapons work within HIPP itself. Although Herrmannsfeldt regards claims for hafnium-178's super-energy
powers as nonsense, he fears that other nations will take them seriously,
triggering a new arms race. Recently, he successfully urged numerous top
scientists to co-sign a letter to Washington officials citing experts'
reservations about the scientific credibility of hafnium-178 claims and asking
for a review of those claims by independent experts.
HIGHLY RESPECTED SKEPTICS
Among the signatories to the Aug. 13 letter to officials at the Defense
Advanced Research Projects Agency (DARPA) and the U.S. Energy Department are
Stanford's Wolfgang Panofsky and Sidney Drell, both grand old men of the
American weapons advisory establishment.
The letter urges the federal government to create an independent panel to
resolve the scientific community's dispute over claims made for the hafnium-
178 "nuclear isomer," as it's called. The government should do so, they stress,
before spending any more money to develop weapons "applications that may not
make physical sense."
Jan Walker, a spokeswoman for DARPA at its Arlington, Va., headquarters,
said the agency is reviewing the letter but declined to discuss the issue.
Walker noted that in conducting advanced research and technology
development for the Defense Department, DARPA has been involved in producing
the technical underpinnings of the Internet, the stealth fighter and bomber,
and unmanned air vehicles such as Global Hawk and Predator.
Some isotopes can experience high-energy, or "nuclear isomer," states in
which they retain abnormal amounts of energy. One of these isotopes is hafnium-
178; its nuclear-isomer state is technically known as hafnium-178m2.
Normally, this nuclear isomer has a half-life of 31 years, meaning half of
it decays away in 31 years. That's way too slow to heat and ignite a
firecracker, much less a super-bomb.
Hafnium is a bright, natural metal. For weapons purposes, the Pentagon
would need large quantities of the particular type called hafnium-178. The
known amount of hafnium-178 nuclear isomer in the world is so small that the
Pentagon would have to mass produce it. No one has a good idea how. The
Pentagon appointed the HIPP panel to try to find out.
One possible way would involve bombarding elements in a giant particle
accelerator, then developing a tedious process for extracting the hafnium-178
nuclear isomer. Some scientists are skeptical that such a technique could be
developed cost effectively -- even if hafnium-178 nuclear isomer proves to be
an exotic energy source as Collins and his colleagues have speculated.
STARTLING ANNOUNCEMENT
In January 1999, an international team led by Collins claimed it had
unleashed startling amounts of energy -- far more than theoretically expected -
- from the hafnium-178 isomer. They did so, they reported in the journal
Physical Review Letters, by bombarding the isotope with X-rays from an
ordinary dental X-ray machine.
(JPM Note: Physical Review Letters allows postings of preliminary reports of experimental results that are startling or novel---these are referreed, but with rapid turnaround...and, occasionally, with only one referee. Thus, the review process is not as stringent...often resulting in controversial, unreproduced results being published).
Besides Collins, the article's 13 co-authors included scientists at the U.S.
Air Force Research Laboratory in Albuquerque; Russia's Joint Institute for
Nuclear Research; and Sandia National Laboratories, a nuclear weapons lab in
New Mexico. Collins himself has a weighty reputation. A decade earlier, the
Texas Academy of Sciences had named him "Distinguished Texas Scientist" of the
year for his research on high-energy lasers.
Elsewhere, other scientists tried to replicate Collins' work by bombarding the isotope with radiation from large particle accelerators, which are far more powerful than the Collins team's dental X-ray machine. Results: negative. One of Collins' original collaborators on the 1999 paper, nuclear physicist James Carroll of Youngstown State University, has since been unable to replicate the Collins experiment on his own. He suspects the energy-unleashing process "is more complex than (Collins) originally thought and needs further study," Carroll said in an interview. Furthermore, scientists from Lawrence Livermore National Laboratory, Los
Alamos National Laboratory and Argonne National Laboratory found "no evidence"
of unusual energy emissions from hafnium-178 exposed to X-rays at Argonne's
hefty Advanced Photon Source accelerator, they reported in Physical Review
Letters in 2001.
The hafnium-178 controversy was also investigated by the members of "Jason,
" which has functioned for decades as a kind of supreme advisory council of
military science. Mostly distinguished physical scientists based at
universities and private companies, these scholars -- often collectively known
as "the Jasons" -- use their expertise to critique the Pentagon's more
ambitious schemes for expensive, futuristic weapons.
CLAIMS CHALLENGED
Claims that hafnium-178 can unleash intense energy are based on experiments that are "poorly characterized and ill-described," Jason member Steve Koonin wrote in 1999, summarizing the group's findings in a letter to the U.S. Arms Control and Disarmament Agency. The claims are "a priori implausible -- extraordinary claims demand extraordinary proof," but that's lacking so far, added Koonin, a nuclear physicist and provost of the California Institute of Technology. "It is extraordinarily unlikely that there is something here" that portends
a new generation of futuristic weapons, Koonin said in a phone interview.
However, he noted that Collins and others have reported new results since 1999,
and that he'd support a new Jason analysis if the Pentagon or Energy
Department requested it.
Collins has stuck to his guns. In a number of e-mail responses to a
Chronicle inquiry, he compared the critics to early 20th century naysayers who
denied the feasibility of atomic energy.
Collins insists his findings have "been confirmed at about all of the
world's third-generation (most advanced) synchrotron radiation sources, except
the DOE facility at Argonne. . . . Naturally, that causes controversy, but it
is a strength of the scientific method that continued study and measurement
will resolve the controversy."
One reason some critics have been unable to verify his original claim,
Collins said, is that their instrument was "blind" to one of the spectral
lines, the so-called 130 line, that he used in measuring energy from hafnium-
178. Hence, "they could not possibly have seen the results" even "if they had
succeeded in doing it."
But physicist John Becker of Lawrence Livermore said that to the best of
his knowledge, no scientist has verified Collins' claim except Pat McDaniel, a
researcher at Sandia who was one of Collins' original collaborators. McDaniel
has not published his results, Becker said. McDaniel could not be reached for
an interview.
"I don't think there's any controversy at all: We've done two experiments, and we cannot reproduce his (Collins') results," Becker said in an interview. The Becker team has used instruments that are "a hundred thousand times more sensitive" than Collins' dental X-ray machine, and "in spite of our best efforts, we cannot reproduce those results." The Pentagon isn't discouraged by skeptics' doubts about the hafnium-178
isomer. In fact, it's trying to figure out how to mass produce the stuff.
According to one knowledgeable source who insisted on anonymity, a full-scale
hafnium-178 facility, if approved, "would probably (cost) tens to hundreds of
millions of dollars."
At one Pentagon Web site, dubbed the Military Critical Technologies List,
under the section titled "Armaments and Energetic Materials," the text
explains that hafnium-178's reported "extraordinary energy density has the
potential to revolutionize all aspects of warfare."
Recently, amid their post-Iraq-war anxieties over U.S. military and foreign
policy, European media have sounded an alarm about possible hafnium-178
weapons. New Scientist, a respected popular science journal in England, ran a
story on Aug. 13 declaring, "Gamma-ray Weapons Could Trigger Next Arms Race."
By coincidence, that same day, five members of the HIPP panel and 10 other experts signed a letter to federal officials citing "the numerous objections raised by the (Jasons) and others over any projected use of the hafnium isomer. " The letter urged the officials to launch an independent scientific review of the subject "before proceeding to study (military) applications that may not make physical sense." E-mail Keay Davidson at kdavidson@sfchronicle.com.
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