TEHRAN – More than 90 top U.S. nuclear scientists have written a letter to Congress urging it to protect the 2015 nuclear agreement with Iran.

The letter reads as follows:

October 30, 2017

Senator Bob Corker, Chairman, Senate Foreign Relations Committee
Senator Ben Cardin, Ranking Member, Senate Foreign Relations Committee
Representative Ed Royce, Chairman, House Foreign Affairs Committee
Representative Eliot Engel, Ranking Member, House Foreign Affairs Committee
Dear Senators Corker and Cardin, and Representatives Royce and Engel

The United States Congress has momentous responsibilities with regard to the nuclear agreement with Iran. As scientists who understand the physics and technology of nuclear power, of nuclear explosives, and of long-range missiles; and who collectively bring experience with nuclear nonproliferation, we would like to provide you with our perspective on the wisest path forward.

Recent statements by the United Kingdom, France, Germany, the European Union, and Iran make clear that renegotiation of the Joint Comprehensive Plan of Action (JCPoA) is an unrealistic objective. Since the JCPoA imposes strict restrictions and strong verification on Iran’s nuclear program, Congress should act to ensure that the United States remains a party to the agreement. Along with assuring the continuation of the agreement, this will allow the United States to influence its implementation, including inspections at military installations, through its position on the Joint Commission.

The JCPoA does not cover non-nuclear activities by Iran; any such issues could be addressed separately. For example, recent reports suggest that Iran might be open to mutually respectful negotiations addressing limits to Iran’s missile program. We encourage you to recommend that the United States pursue this potential opportunity.

President Trump has expressed concerns about the long-term implications of the JCPoA for Iran’s nuclear program. The severe restrictions on Iran’s stockpile of low-enriched uranium remain in place through 2030, and continuous surveillance of Iran’s centrifuge production through 2035. Surveillance of uranium mines and mills remains through 2040. Thereafter, Iran returns fully to International Atomic Energy Agency (IAEA) safeguards under the “Additional Protocol,” the strongest set of generally applicable safeguards implemented by the IAEA. In contrast, during most of its prior history, Iran’s nuclear program was subject only to the minimum level of IAEA safeguards.

There are additional measures that would make it more difficult for any country with enrichment facilities to produce secretly material for weapons. First, it would be valuable to have stronger verification procedures at uranium enrichment plants worldwide. In particular, the IAEA should implement real-time verification at large-scale uranium enrichment plants in non-nuclear weapon states where the IAEA is unable to reach a “Broader Conclusion” of the absence of undeclared nuclear materials and activities.

Second, multi-national control of uranium enrichment plants—such as a strengthened version of the arrangements within the European company URENCO—could provide an extra layer of security against their misuse to produce material for nuclear weapons, due to oversight by officials of multiple nationalities. Congress should recommend that the Executive Branch, in collaboration with all other member states of the IAEA and the IAEA itself, work to strengthen uranium enrichment plant safeguards worldwide, and implement multi-national control of uranium enrichment capabilities. Continuation of the JCPoA is necessary to provide the time needed to develop and implement these initiatives.

We hope that you will take into account the perspectives presented here. We stand ready to discuss these matters in more detail with you at your request.

Sincerely

Richard L. Garwin
Member of the National Academies of Sciences, Engineering and Medicine
National Medal of Science (2002)
Presidential Medal of Freedom (2016)

Robert J. Goldston
Professor, Astrophysical Sciences, Princeton University

Rush Holt
Chief Executive Officer, American Association for the Advancement of Science

R. Scott Kemp
Associate Professor, Nuclear Science and Engineering, MIT
Director, MIT Laboratory for Nuclear Security and Policy

Frank von Hippel
Senior Research Physicist and Professor of Public and International Affairs, Emeritus,
Princeton University
(Affiliations for identification only)
All communications should be addressed to Robert Goldston at rjg@Princeton.edu
Additional signatories on the following pages:
October 30, 2017 Scientist’s Letter to Congress on Iran Deal 3

Also signed by:

Elihu Abrahams
Department of Physics and Astronomy, UCLA
Member of the National Academy of Sciences

James Acton
Co-director, Nuclear Policy Program, Carnegie Endowment for International Peace
Stephen L. Adler Professor Emeritus, School of Natural Sciences, Institute for Advanced Study Member of the National Academy of Sciences

Peter Agre
Bloomberg Distinguished Professor and Director, Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health
Member of the National Academy of Sciences
Nobel Prize (Chemistry, 2003)
Barry C. Barish Linde Professor of Physics, Emeritus, California Institute of Technology
Member of the National Academy of Sciences Nobel Prize (Physics, 2017)

R. Stephen Berry
James Franck Distinguished Service Professor Emeritus, Department of Chemistry, The University of Chicago Member of the National Academy of Sciences
William Bialek John Archibald Wheeler/Battelle Professor in Physics, Princeton University Visiting Presidential Professor of Physics, The Graduate Center, City University of New York Member of the National Academy of Sciences

Steven M. Block
S.W. Ascherman Professor of Sciences, Stanford University
Member of the National Academy of Sciences

William F. Brinkman
Senior Physicist, Physics Department, Princeton University
Vice President of Research, retired, Bell Laboratories
Member of the National Academy of Sciences
October 30, 2017 Scientist’s Letter to Congress on Iran Deal 4
Matthew Bunn Professor of Practice, John F. Kennedy School of Government, Harvard University

Claude R. Canizares
Rossi Professor of Physics, MIT Member of the National Academy of Sciences

Roberto Car
Ralph W. Dornte '31 Professor in Chemistry, Princeton University Member of the National Academy of Sciences

Moses H. Chan
Evan Pugh University Professor of Physics, Penn State University Member of the National Academy of Sciences

Christopher F. Chyba
Professor of Astrophysical Sciences and International Affairs, Princeton University
George W. Clark Breene M. Kerr Professor of Physics, Emeritus, MIT Member of the National Academy of Sciences

Morrel H. Cohen
Department of Physics and Astronomy, Rutgers University
Department of Chemistry and Chemical Biology, Princeton University
Member of the National Academy of Sciences

Leon N. Cooper
Thomas J. Watson, Professor of Science, Brown University
Member of the National Academy of Sciences Nobel Prize (Physics, 1972)

Susan N. Coppersmith
Robert E. Fassnacht Professor of Physics, University of Wisconsin at Madison
Member of the National Academy of Sciences

Pierce S. Corden
Former Director, Office of International Security Negotiations, Department of State
John M. Cornwall Distinguished Professor of Physics, Emeritus, UCLA

Stanley Deser
Senior Research Associate, California Institute of Technology Member of the National Academy of Sciences
October 30, 2017 Scientist’s Letter to Congress on Iran Deal 5

Bruce T. Draine
Professor of Astrophysical Sciences, Princeton University Member of the National Academy of Sciences

Freeman Dyson
Professor Emeritus, Institute for Advanced Study
Member of the National Academy of Sciences Enrico Fermi Award (1995)

James P. Eisenstein
Roshek Professor of Physics and Applied Physics, California Institute of Technology Member of the National Academy of Sciences

Harold A. Feiveson
Program on Science and Global Security, Princeton University

Steve Fetter
Professor, School of Public Policy, University of Maryland

Daniel S. Fisher
Professor of Applied Physics, Stanford University Member of the National Academy of Sciences

Eduardo Fradkin
Donald Biggar Willett Professor of Physics and Director, Institute for Condensed Matter Theory, University of Illinois at Urbana-Champaign
Member of the National Academy of Sciences
Jerome I. Friedman Institute Professor and Professor of Physics Emeritus, MIT Member of the National Academy of Sciences
Nobel Prize (Physics, 1990)

Mary K. Gaillard
Professor of the Graduate School, University of California at Berkeley Member of the National Academy of Sciences

Howard M. Georgi
Mallinckrodt Professor of Physics, Harvard University
Member of the National Academy of Sciences
Subrata Ghoshroy Research Affiliate, Program in Science, Technology, and Society, MIT
October 30, 2017 Scientist’s Letter to Congress on Iran Deal 6

Sheldon Lee Glashow
Arthur G.B. Metcalf Professor of Mathematics and the Sciences, Boston University
Member of the National Academy of Sciences
Nobel Prize (Physics, 1979)

Roy Glauber
Mallinckrodt Professor of Physics Emeritus, Harvard University
Member of the National Academy of Sciences Nobel Prize (Physics, 2005)

Allen M. Goldman
Regents Professor of Physics, University of Minnesota
Member of the National Academy of Sciences

Kurt Gottfried
Professor of Physics, Emeritus, Cornell University

Lisbeth Gronlund
Senior Scientist and Co-Director, Global Security Program, Union of Concerned Scientists

David Gross
Chancellor’s Chair Professor of Theoretical Physics, University of California at Santa Barbara
Member of the National Academy of Sciences
Nobel Prize (Physics, 2004)

Stephen E. Harris
Professor of Electrical Engineering and Applied Physics, Emeritus, Stanford University Member of the National Academies of Sciences and Engineering
Siegfried S. Hecker
Center for International Security and Cooperation, Stanford University Former Director of the Los Alamos National Laboratory
Member of the National Academy of Engineering

Martin E. Hellman
Professor Emeritus of Electrical Engineering, Stanford University Member of the National Academy of Engineering
Dudley Herschbach
Professor of Physics and Chemistry, Texas A&M University at College Station
Member of the National Academy of Sciences National Medal of Science (1991)
Nobel Prize (Chemistry, 1986)
October 30, 2017 Scientist’s Letter to Congress on Iran Deal 7

Roald Hoffmann
Frank H.T. Rhodes Professor of Humane Letters, Emeritus, Cornell University
Member of the National Academy of Sciences
National Medal of Science (1983)
Nobel Prize (Chemistry, 1981)

Pierre C. Hohenberg
Professor Emeritus of Physics, New York University
Member of the National Academy of Sciences

John P. Holdren
Science and Technology Advisor to President Obama (2009–2017) Professor, Kennedy School of Government and Department of Earth and Planetary Sciences, Harvard University
Member of the National Academy of Sciences

Raymond Jeanloz
Professor of Earth and Planetary Sciences and Astronomy, University of California at Berkeley
Chair, National Academy of Sciences Committee on International Security and Arms Control
Member of the National Academy of Sciences

Steven Kivelson
Prabhu Goel Family Professor of Physics, Stanford University
Member of the National Academy of Sciences

Daniel Kleppner
Lester Wolfe Professor of Physics Emeritus, MIT
Member of the National Academy of Sciences
National Medal of Science (2006)

Lawrence M. Krauss
Foundation Professor, School of Earth and Space Exploration, Arizona State University

Don Q. Lamb
Robert A. Millikan Distinguished Service Professor Emeritus, Department of Astronomy & Astrophysics and Harris School of Public Policy, University of Chicago
Frederick K. Lamb Research Professor of Physics; Core Faculty Member, Program in Arms Control & Domestic and International Security; Brand and Monica Fortner Endowed Chair of Theoretical Astrophysics Emeritus; Professor of Physics and Professor of Astronomy Emeritus, University of Illinois at Urbana-Champaign
October 30, 2017 Scientist’s Letter to Congress on Iran Deal 8

Neal Lane
Senior Fellow, Baker Institute for Public Policy; University Professor Emeritus, and Professor of Physics and Astronomy Emeritus, Rice University
National Academy of Sciences Public Welfare Medal (2009)

David M. Lee
Distinguished Professor of Physics and Astronomy, Texas A&M University at College Station
Member of the National Academy of Sciences Nobel Laureate (Physics, 1996)

Anthony J. Leggett
Professor of Physics, University of Illinois
Member of the National Academy of Sciences Nobel Prize (Physics, 2003)

Elliott Lieb
Higgins Professor of Physics and Professor of Mathematics, Princeton University
Member of the National Academy of Sciences
Gregory A. Loew Emeritus Deputy Director and Professor, SLAC National Accelerator Laboratory

Edwin Lyman
Senior Scientist, Global Security Program, Union of Concerned Scientists

John C. Mather
Member of the National Academy of Sciences Nobel Prize (Physics, 2006)

M. Brian Maple
Distinguished Professor of Physics, University of California at San Diego
Member of the National Academy of Sciences

Nergis Mavalvala
Professor of Physics, MIT
Member of the National Academy of Sciences

N. David Mermin
Horace White Professor of Physics Emeritus, Cornell University
Member of the National Academy of Sciences

Marvin Miller
Science, Technology, and Society Program, MIT
October 30, 2017 Scientist’s Letter to Congress on Iran Deal 9
William E. Moerner Professor of Chemistry and Applied Physics, Stanford University
Member of the National Academy of Sciences Nobel Laureate (Chemistry, 2014)
Norman P. Neureiter Senior Advisor, International, American Association for the Advancement of Science
National Academy of Sciences Public Welfare Medal (2008)

David Nygren
Presidential Distinguished Professor, University of Texas at Arlington Member of the National Academy of Sciences

John A. Parmentola
Former Director for Research and Laboratory Management, U.S. Army Former Senior Vice President for Energy and Advanced Concepts, General Atomics

C. Kumar N. Patel
Professor Emeritus, Department of Physics and Astronomy, UCLA
Member of the National Academies of Sciences and Engineering

Claudio Pellegrini
Distinguished Professor of Physics and Astronomy, Emeritus, UCLA
Member of the National Academy of Sciences

William D. Phillips
Professor of Physics, University of Maryland at College Park
Member of the National Academy of Sciences
Nobel Prize (Physics, 1997)

David Pines
Distinguished Research Professor of Physics, University of California at Davis; Research Professor of Physics, University of Illinois at Urbana-Champaign; Founder-in-Residence, Santa Fe Institute Member of the National Academy of Sciences

Theodore A. Postol
Professor Emeritus of Science, Technology, and National Security Policy, MIT

David E. Pritchard
Cecil and Ida Green Professor of Physics, MIT
Member of the National Academy of Sciences

Helen R. Quinn
Professor Emerita, Particle Physics and Astrophysics, Stanford University
Member of the National Academy of Sciences
October 30, 2017 Scientist’s Letter to Congress on Iran Deal 10

John D. Reppy
John L. Wetherill Professor Emeritus of Physics, Cornell University
Member of the National Academy of Sciences

Burton Richter
Paul Pigott Professor of Physical Sciences Emeritus, Stanford University
Member of the National Academy of Sciences
National Medal of Science (2014)
Nobel Laureate (Physics, 1976)

Myriam P. Sarachik
Distinguished Professor of Physics, City College of New York, City University of New York
Member of the National Academy of Sciences

John H. Schwarz
Harold Brown Professor of Theoretical Physics Emeritus, California Institute of Technology Member of the National Academy of Sciences

Roy F. Schwitters
S. W. Richardson Regents Professor of Physics, The University of Texas at Austin

Frank Sciulli
Pupin Professor of Physics Emeritus, Columbia University
Member of the National Academy of Sciences

Stephen Shenker
Richard Herschel Weiland Professor of Physics, Stanford University
Member of the National Academy of Sciences

Melvyn Shochet
Kersten Distinguished Service Professor of Physics, University of Chicago
Member of the National Academy of Sciences

Joseph H. Taylor, Jr.
James S. McDonnell Distinguished University Professor of Physics, Emeritus, Princeton University Member of the National Academy of Sciences
Nobel Prize (Physics, 1993)

Max Tegmark
Professor of Physics, Massachusetts Institute of Technology
October 30, 2017 Scientist’s Letter to Congress on Iran Deal 11

Kip S. Thorne
Feynman Professor of Theoretical Physics Emeritus, California Institute of Technology
Member of the National Academy of Sciences Nobel Prize (Physics, 2017)

Maury Tigner
Director Emeritus, Laboratory of Nuclear Studies, Cornell University
Member of the National Academy of Sciences
Scott Tremaine Professor, Institute for Advanced Study, Princeton Member of the National Academy of Sciences

George H. Trilling
Professor of Physics Emeritus, University of California at Berkeley
Member of the National Academy of Sciences

Rainer Weiss
Professor of Physics Emeritus, MIT Member of the National Academy of Sciences Nobel Prize (Physics, 2017)
Ray J. Weymann Director Emeritus, Carnegie Observatories, Carnegie Institution for Science
Member of the National Academy of Sciences

David J. Wineland
Member of the National Academy of Sciences
National Medal of Science (2007)
Nobel Prize (Physics, 2012)

David Wright

Senior Scientist and Co-Director, Global Security Program, Union of Concerned Scientists

(Affiliations for identification only)