* West fears research reactor could yield bomb material
* Iran says heavy-water plant to produce medical isotopes
* Sticking point in nuclear talks between Iran and powers
* Princeton experts say proposal would reduce plutonium
By Fredrik Dahl
VIENNA, April 2 Changes to the design of Iran's
planned Arak research reactor could drastically reduce its
output of potential nuclear weapon material, U.S. experts said
in a proposal.
How to deal with Arak is one of several issues that must be
tackled in negotiations between Iran and six global powers that
got under way in February with the aim of reaching a long-term
deal on the decade-old nuclear dispute by late July.
Princeton University academics said that annual production
of plutonium could be cut to less than a kilogram - well below
the roughly eight kg needed for an atomic bomb - if Iran altered
the way the plant is fuelled and lowers its power capacity.
"These redesigns would not reduce the usefulness of the
reactor for making radioisotopes and conducting research,"
wrote Ali Ahmad, Frank von Hippel, Alexander Glaser and Zia Mian
- members of Princeton's Program on Science and Global Security.
"This approach would meet Iran's needs and would address the
concerns of the international community," said their article,
due to be published on Wednesday by the on-line journal of the
Arms Control Association, a U.S. research and advocacy group.
Iran denies Western allegations that it is seeking the
capability to make nuclear bombs, saying its programme is aimed
at generating electricity and carrying out peaceful research.
Experts from Iran and the United States, Russia, France,
Germany, Britain and China are due to meet in Vienna for three
days from Thursday to be followed by a third round of
political-level talks next week.
Western powers fear Arak could provide a supply of plutonium
- one of two materials, along with highly enriched uranium, that
can trigger a nuclear explosion - once operational.
The Islamic Republic has said that the 40-megawatt,
heavy-water reactor is intended to produce isotopes for cancer
and other medical treatments. Iran agreed to halt installation
work at Arak under an interim deal reached with the powers last
Their positions seem far apart. Iran has ruled out shutting
down any nuclear site, including Arak, which has been under
construction for years. The United States says it sees no need
for Arak as part of a civilian nuclear programme.
WIN-WIN SOLUTION FOR ARAK?
However, the head of Iran's atomic energy organisation, Ali
Akbar Salehi, in February signalled some flexibility, saying it
was prepared to modify Arak to help allay any concerns.
Heavy-water reactors, fuelled by natural uranium, are seen
as especially suitable for yielding plutonium. To do so,
however, a nuclear reprocessing plant would also be needed to
extract the plutonium. Iran is not known to have any such plant.
If operating optimally, Arak could produce about nine kg of
plutonium annually, the U.S. Institute for Science and
International Security says.
Any long-term deal must lower that amount, experts say.
The Princeton University experts said that changing Arak's
fuelling and operating power would make it less of a
proliferation concern, even if it were to remain a heavy
"The conversion steps described above are technically
feasible," they said in the article titled "A Win-Win Solution
for Iran's Arak Reactor".
Robert Einhorn, a former U.S. State Department official on
Iran, said that at a minimum using enriched uranium fuel and
reducing the power level would be required for Arak. But he said
it would preferably also be converted to a light-water reactor,
a more extensive reconfiguration step that Iran may resist.
Arak was still a less immediate concern than Iran's existing
uranium enrichment programme, which gives it the ability to
produce enough weapons-grade uranium for a bomb in a couple of
months, Einhorn said in a new report.
(Editing by Angus MacSwan)