Capacity building in neutron and reactor physics


  • Alvie Asuncion-Astronomo ⋅ PH Philippine Nuclear Research Institute, Department of Science and Technology


Neutrons interact with matter in ways that make them ideal for applications in various fields like nuclear physics, environmental science, biomedical research, material science, and reactor physics among others. Most of these applications require high neutron fluences that are generated by nuclear facilities such as a research reactor. However, there has been no operating nuclear facility in the Philippines for more than three decades. This resulted in the decline of expertise in nuclear science and neutron physics as well as the limited availability of neutron applications in the country. To address this challenge, the Philippine Nuclear Research Institute (PNRI) has been implementing capacity building activities by establishing facilities and utilizing existing radiation sources and nuclear materials in the Institute.

Isotopic neutron sources (INS) that were previously disused were characterized using a Monte Carlo radiation transport code. Calculated results were complemented by measurements that utilize both active and passive neutron detectors. INS that are completely characterized will then be repurposed for optimized use. On the radiation safety aspect, neutron spectrometry and dosimetry are revived by establishing a neutron laboratory and developing an in-house neutron spectrometry system (NSS). The neutron laboratory has been hosting students and researchers since 2017, while the NSS has been deployed to assess neutron fields in medical accelerators. Another major activity is the reoperation of the Philippine Research Reactor-1 (PRR-1) by reusing the existing nuclear fuel in a subcritical assembly (SCA). SCAs contain a reactor core that produce neutrons without achieving criticality or self-sustained chain fission reaction. Although it will have limited capabilities, SCAs are flexible and can be utilized for applications that are ideal for countries (re)starting a nuclear science and technology program like the Philippines.

In this talk, major milestones of the PNRI capacity building activities will be presented with emphasis on the establishment of the PRR-1 Subcritical Assembly for Training, Education, and Research (SATER). The corresponding challenges and opportunities will be described as well as the potential contribution of the Philippines as a developing country in the field of neutron and reactor physics.

About the Speaker

Alvie Asuncion-Astronomo, Philippine Nuclear Research Institute, Department of Science and Technology

Alvie Asuncion-Astronomo is the Head of the Nuclear Reactor Operations Section of the DOST-Philippine Nuclear Research Institute (PNRI). Her current research activities focus on characterization of neutron fields and reactor core configurations. She is the lead person implementing the project to re-establish the Philippine Research Reactor-1 (PRR-1) as a Subcritical Assembly for Training, Education, and Research (SATER). She is also the lead developer of a novel design for a neutron spectrometry system that is used to characterize neutron fields in medical accelerators. Alvie obtained her B.Sc. in Physics for Teachers from the Philippine Normal University (PNU) where she graduated batch valedictorian in 2005. Her M.Sc. and Ph.D. in Physics degrees were both obtained from Ateneo De Manila University in 2010 and 2017, respectively.



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Invited Presentations



How to Cite

A Asuncion-Astronomo, Capacity building in neutron and reactor physics, Proceedings of the Samahang Pisika ng Pilipinas 38, SPP-2020-INV-3B-01 (2020). URL: