Seminar: Nuclear Security: detection and verification of nuclear materials

In its list of Grand Engineering Challenges for 21st century, the National  Academy of Engineering lists Nuclear Security, along with developing fusion energy, among its fourteen challenges. If the peaceful use of fission energy is to continue taking place, then we are faced with issues of proliferation, arms control, as well as the dangers of nuclear terrorism.

Monochromatic sources for cargo inspection

A common method of inspecting commercial cargoes for the presence of fissile materials involves the use of 1-10MeV bremsstrahlung photon beams. While simple and reliable, this technique has significant limitations, such as the high doses necessary to achieve Z-discrimination. Much progress in the field of active interrogation can be achieved by developing monoenergetic sources, as these will allow for lower dose radiography and photofission based active interrogation. Currently, a collaboration lead by MIT is researching a
new technique which uses proton and deuteron beams in ¹¹B(d,nγ)¹²C and ¹²C(p,p’γ)¹² C reactions, which produce highly monoenergetic photons.This program makes use of a 3MeV deuteron source at MIT-Bates linear accelerator to experiment with (d,nγ) reactions. This approach can be used to achieve low dose dual energy radiography, as well as enable fissionable material detection via photofission.

Nuclear arms reduction and treaty verification

Arms reduction is an important part of improving global security. The New START treaty limits the number of warheads to 1550. The participant states will then be required to demonstrate compliance, while retaining the secrecy of weapons’ design. This will involve proving to an inspection crew that the warheads being dismantled are real, without releasing any direct nuclear or physical information about the weapon structure. Our group is working on a physical cryptography system, which uses transmission NRF (tNRF) to produce a physical “hash” of the weapon. This physically encrypted data is then compared to that from measurements taken on a warhead of known authenticity. This comparison tests the hypothesis that the two weapons
are identical. A successful comparison will help verify the authenticity of the first weapon, and since the comparison is done in cryptographic domain no direct information about the weapon is revealed. The technique, and some of the early results will be presented and discussed.

About the Speaker

Professor Areg Danagoulian is an assistant professor at MIT's Department of Nuclear Science and Engineering.  His background is in experimental nuclear physics. After having completed his PhD at UIUC, Areg moved to Los Alamos National Laboratory, where he worked on a variety of research programs.  These included stockpile stewardship, physics beyond the standard model, and nuclear security. Afterwards, he worked for six years at a private company, Passport Systems, Inc.. Here he developed an award winning active interrogation technique which used fast neutrons for the detection of shielded fissionable materials hidden in cargo containers.  Currently Areg is working on two major programs at MIT:  the monochromatic radiography program, which is funded via DHS’ Academic Research Initiative (ARI);  and physical cryptography for weapons verification, which involved the development of techniques for authentication of nuclear warheads, and is supported by DOE’s Consortium of Verification Technologies (CVT).   

Hosted by Professor Lei R. Cao