Berkeley Nuclear Research Center

... energy for tomorrow

BNRC Researchers

BNRC Researchers

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Visiting Scholars

Marija Pavlovic

Visiting Scholar



Yasmina Rharade

Visiting Scholar



Dr. Tetsushi Hino

Visiting Industrial Fellow


Dr. Michel Kireeff Covo photo_placeHolder

Dr. Dan Chivers

  • Email: This email address is being protected from spambots. You need JavaScript enabled to view it.
    Phone: 510-643-2065
    Fax: 510-643-9685

    UCB Department of Nuclear Engineering
    4109 Etcheverry Hall
    MC 1730
    Berkeley, CA 94720-1730

  • Current Research Activities

    Investigation of electron-track Compton Imaging using high spatial resolution silicon detectors
    Principal Investigator: Dr. Kai Vetter, University of California, Berkeley

    The current limitation in Compton imaging systems is the inability to measure Compton electron trajectories. Using only the knowledge of only the angle of ?-ray scatter, a cone of possible incident trajectories is created by a lack of knowledge of the electron scatter angle. Since the incident photon, scattered photon, and scattered electron are co-planar, sensing the electron trajectory can greatly reduce the systematic background that exists in Compton gamma-ray imaging systems.

    Machine Vision Radiation Detection
    Principle Investigator: Dr. James Siegrist, University of California, Berkeley

    There are many situations where radiation detectors are implemented alongside real-time video streams. This research seeks to identify a methodology of combining visual and spectroscopic data in ways that increase detection sensitivity.

    Pre-detonation Nuclear Forensics

    The standards for security of nuclear materials have been written such that a high degree of interpretation of the standards exist based in part by individual states’ perception of the nuclear terrorist risk and the cost/benefit of implementing higher standards. It is clear from the amount of interdicted materials on the black market that nuclear facilities exist under the Nuclear Nonproliferation Regime that are most likely not secure enough. Pre-detonation nuclear forensics promises to hold states accountable for a lack of security by the attribution of interdicted materials to a state or facility combined with an expectation of international action. The first step in the realization of a global nuclear forensics effort is the development of domestic unclassified nuclear forensics laboratories that work to build a database of signatures and perform research and new signature development.

  • Education

    Doctorate of Philosophy
    Nuclear Engineering
    Dissertation: “Advanced Modeling Techniques for Signal Decomposition of Planar Double-Sided Strip Detectors”
    Research Advisor: Dr. Kai Vetter, Lawrence Livermore National Laboratory
    Academic Advisor: Dr. Stanley Prussin, Nuclear Engineering Department

    Minor Concentrations:
    Complex System Risk Assessment & Management
    -Terrorist Network Emergence: A Study in Risk Management

    Energy and National Security Policy
    -Proliferation Security Initiative: A Policy Analysis
    -Market Based Approaches to Energy and Environmental Protection

    Bachelor of Science
    Nuclear and Electrical Engineering

    Areas of Concentration:
    -Interaction of radiation with matter
    -Signal processing and control systems
    -Particle transport modeling

    Compton Imaging using Time Projection Chambers
    Design of Neutron Beam Shaping Assembly using MCNP

    United States Navy
    Naval Nuclear Power School, Orlando, FL 1993

    Areas of Concentration:
    Nuclear physics
    Reactor operations
    Reactor Instrumentation

  • Teaching Experience

    University of California, Berkeley
    Graduate Lecturer – “Neutron Transport”
    Developed additional lectures for undergraduate course in neutron transport.

    Naval Nuclear Staff Instructor, Idaho National Laboratory
    Developed seminars on physics of a naval nuclear power plant.
    Trained nuclear power pipeline students in operation & maintenance procedures.

  • Publications

    “Before the Day After: Using Pre-Detonation Nuclear Forensics to Improve Fissile Material Security”, July, 2008, Arms Control Today.
    “Advanced Modeling Techniques for Signal Decomposition of Planar HPGe Double-Sided Strip Detectors”, 2006, IEEE Nuclear Science Symposium San Diego
    “Model Simulations of 3D Gamma-Ray Imaging for Nuclear Safeguards”, 2006 ,INMM Annual Meeting, Nashville, TN.
    “First-Generation Hybrid Compact Compton Imager”, 2005, IEEE Nuclear Science Symposium, Fajardo, PR.
    “Imaging Performance of the Si/Ge Hybrid Compton Imager”, 2005, IEEE Nuclear Science Symposium, Fajardo, PR.
    “A Compact BNCT Facility using a Fusion Neutron Source and a Fission Multiplier”, presented at 2002 ANS, Washington D.C. (2002). Awarded Winner of the ANS National Student Design Competition.

Jor-Shan Choi

BNRC Researchers | BNRC | Table

choiDr. Jor-Shan Choi is a Project Professor for the Global Center-of-Excellence (G-COE) Program at the Department of Nuclear Engineering and Management, the University of Tokyo (UT), Japan. His areas of research and study include non-proliferation policy, proliferation-resistant technologies, 3S (safety, security, and safeguards), internationalization of nuclear fuel cycle, and regional cooperation on peaceful use of nuclear energy. Before joining UT in 2008, Dr. Choi worked for Lawrence Livermore National Laboratory (LLNL) in California, USA for 21 years, developing novel fuels for advanced small reactors and novel corrosion-resistant material for spent-fuel waste containers. He was a delegation member for the HEU blend-down program, the weapons-plutonium disposition program, and the proliferation-resistance and physical protection (PR&PP) international working group. He was also responsible for fissile material safety, security and vulnerability in his role as criticality-safety officer for LLNL’s Plutonium Facility.

Dr. Choi was a Science Fellow at the Center for International Security and Cooperation (CISAC), Stanford University in 1995-96. He worked at the International Atomic Energy Agency (IAEA) in Vienna from 1998-2001. Prior to joining LLNL in 1987, Dr. Choi had 13 years of industrial experience working for Bechtel. He has a BSEE in Electrical Engineering and Computer Science, a MS and a PhD in Nuclear Engineering, all from the University of California at Berkeley. He is also a registered Professional Engineer (PE) in California

Researchers at BNRC



Dr. Bethany Lyles Goldblum Assistant Director Dr_Lyles
Dr. Robert Angelo Borelli photo_placeHolder

Affiliated Researchers

Nick Brickner

 UC Berkeley  Nick Brickner
Dr. Robert Budnitz LBNL Budnitz
Dr. Bernhard Ludewigh LBNL photo_placeHolder
Dr. David McCallen LLNL McCallen
Dr. Kathryn McCarthy INL photo_placeHolder
Dr. Nan Sauer LANL photo_placeHolder
Dr. Nicholas Scielzo Physics and Life Sciences Divison at LLNL photo_placeHolder
Dr. Sara Scott LANL Sara_Scott


Dr. Steve Tobin
LANL photo_placeHolder

Vladimir Mozin



International Affiliated Researchers

Dr. Yongsoo Hwang

KAERI, Korea


Ryan Yee

Yee_Ryan Ryan Yee

Graduate Student Research Assistant

Ryan Yee received a B.Sc. in Engineering Physics from Queen’s University in Kingston, Ontario, Canada in 2006 and a M.S. in Nuclear Engineering from UC Berkeley in 2009. Prior to entering graduate school, he was a Scientist at Rapiscan Labs working on neutron-based active interrogation systems for homeland security. His current interests are beta-delayed neutron spectroscopy using trapped radioactive ions, and other applications of radiation detection systems.

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