Prof. Alireza Haghighat

Affiliation: Professor and Director of the Virginia Tech Nuclear Engineering Program, Mechanical Engineering Department, and Director of Nuclear Science and Engineering Lab (NSEL) and the Mechanical Engineering Program at the National Capital Region (NCR) Campus, Arlington, VA

Prof. Alireza Haghighat Short bio

Dr. Haghighat is professor and Director of the Virginia Tech Nuclear Engineering Program, Mechanical Engineering Department.  He is also the Director of Nuclear Science and Engineering Lab (NSEL) and the Mechanical Engineering Program at the National Capital Region (NCR) Campus, Arlington, VA. In addition to graduate degrees, at VT has contributed to a new graduate Certificate in Nuclear Science, Technology and Policy (NuSTEP), and accelerated program for the US Naval Academy. Prof. Haghighat is the former (2001-2009) Chair of the University of Florida (UF) Nuclear & Radiological Engineering (NRE) Department and former (2008-2010) Director of UF Training Reactor. Prior to Florida, Prof. Haghighat was a faculty member at the Pennsylvania State University for 15 years. Prof. Haghighat is a fellow of the American Nuclear Society (ANS). He leads the Virginia Tech Theory Transport Group (VT3G). Over the past 32 years, Prof. Haghighat has been involved in the development of new particle transport methodologies and large computer codes for modeling and simulation of nuclear systems including reactors, nuclear security and safeguards systems and medical devices. His efforts has resulted in the development of several advanced computer programs including PENTRAN, A3MCNP, TITAN, INSPCT-s, AIMS, TITAN-IR, and RAPID. For the latter code system, a virtual reality system (VRS) web application has been developed. To learn more about VRS-RAPID, view a demo at He has published over 250 papers, received several best paper awards, and presented numerous invited workshops, seminars and papers nationally and internationally. In Dec 2014, he published a textbook entitled ‘Monte Carlo Methods for Particle Transport’, CRC Press Taylor & Francis Group; currently, he is working on the 2nd edition of his book. He is recipient of the 2011 Radiation Protection Shielding Division’s Professional Excellence Award, and recognition award from Office of Global Threat Reduction for his leadership & contributions to design and analysis for the University of Florida Training Rector HEU to LEU fuel conversion, 2009. Prof. Haghighat is an active member of the American Nuclear Society, and has served at various leadership positions. He has served as Chair of the Reactor Physics Division (2012-13) and the Mathematics and Computation Division (2005-06), was co-founder of the Computational Medical Physics Working Group, and served as Chair of NEDHO (Nuclear Engineering Department Heads Organization) (2006-07). Prof. Haghighat contributed to the formation of the SUNRISE (Southeast Universities Nuclear Reactors Institute for Science and Education) not-for-profit organization, and served as Chairman of the Board of SUNRISE since June 2010-2013. In 2015, he contributed to the formation of the Virginia Nuclear Energy Consortium (VNEC) nonprofit organization; he is the founding Chairman of the board of this organization (2015-2016), and Vice-chair (2017-2018). Currently, he serves as the Chairman of the Board for the second time (for further information on VNEC, visit

Presentation Title: High Fidelity Neutronics Software, uncertainty quantification, and Research Reactors

Abstract of presentation:

Particle transport simulation of nuclear systems is essential for their design, optimization, operation and monitoring. Fast and accurate high fidelity calculation methodologies that are well benchmarked against experimental systems are needed. In the past, i.e., existing reactor technology, simulation tools have relied on somewhat coarse models with approximate methodologies that benefited from two main factors: i) allowance for large margins and tolerances; ii) ability to construct test reactors for adjustment of approximate methodologies. Neither factor can be expected for the development of high fidelity software that are needed for the design, analysis, licensing of the advanced nuclear technologies. This paper argues the need for new computational paradigms, e.g., the MRT (Multi-stage, Response-function Transport) methodology which has resulted in the development of the novel high-fidelity RAPID (Real-time Analysis for Particle-transport and In-situ Detection) code system. Such code systems have to be robust in modeling any complex system, and should be fast and accurate, henceforth their uncertainties can be quantified at reasonable costs. Due to the lack of access to test reactors, well-characterized and robust research reactors with appropriate environments and high-fidelity, high-precision measurements capability are needed. Such robust facility is offered by the Josef Stefan Institute (JSI) TRIGA reactor and its unique experimental capabilities. Examples of the high fidelity benchmarking studies of RAPID using the JSI’s TRIGA will be discussed.