Prof. Dr. rer. nat. Imam Fachruddin, S.Si., M.Si. was inaugurated as a Permanent Professor of the Faculty of Mathematics and Natural Sciences (FMIPA) University of Indonesia (UI) in the field of Mathematics. Few-Body Nuclear Physics by the Chancellor of UI, Prof. Dr. Ir. Heri Hermansyah, S.T., M.Eng., IPU., on Wednesday (12/2), at the UI Depok Campus Convention Hall.
In a scientific speech entitled “Calculations without Partial Wave Decomposition for Multiple Hadron Systems”, Prof. Imam said that in the field of Nuclear Physics, Few-Body Nuclear Physics taking a system consisting of several hadrons as the object of research. Hadrons are subatomic particles that contain quark, antiquark, And gluon, which are used in radiotherapy and particle physics research. The system of several hadrons is studied, both in the bound state (bound state), and scattering (scattering) which includes elastic scattering and rupture processes (breakup).
High energy scattering studies are needed to reveal the nature of interactions in systems of several hadrons with very small distances. Calculations for long-range interactions are needed to see electromagnetic effects in such systems. At high energies and/or for long-range interactions the number of partial waves to be considered is very large. This causes great complexity and workload, both analytically and numerically.
For that, Prof. Imam offers calculations without partial wave decomposition as an alternative. With this technique, all partial waves are included, so that the calculation does not depend on the energy and range of interaction. The calculation results show agreement between calculations without and with partial wave decomposition.
In his research, he showed the convergence process of partial wave decomposition calculations with increasing energy for scattering cross-sections with a total spin of ½. At higher energies more partial waves are needed. The convergence process can also be seen from the difference between partial wave decomposition calculations and those without partial wave decomposition.
In addition, variations of partial waveless calculation techniques have also been developed and applied to various systems and processes. These techniques have shown good results. One example is the system kaon-nukleon.
“We have succeeded in developing a partial waveless calculation technique for such systems. With this technique, we are trying to obtain one-hadron-exchange-potential For kaon-nukleon, inspired by success one-boson-exchange-potential For nukleon-nukleon, although it has not been successful. At the same time, we are also working on a partial waveless calculation technique for a system of two spin ½ particles, whether the two particles are identical or not,” said Prof. Imam.
From this research, he found that calculations without partial wave decomposition were in good agreement with calculations with partial wave decomposition, especially at low energies and for
short-range interactions. This calculation can also be used for both low and high energy regions. In addition, this technique is indispensable for calculations of high-energy scattering and/or scattering triggered by long-range interactions, as well as scattering of more than two particles.
Prof. Imam’s research on calculations without partial wave decomposition shows expertise in the field of Science. Few-Body Nuclear Physics. Some of his research related to this topic, including: An Approach without Partial Wave Expansion to Calculate Scattering of Spin-0 and Spin-1/2 Particles in High Energy Regions and Those Governed by Long Range Interactions (2024); Effect of Spin-5/2 Propagator on Η-Photoproduction on Proton (2024); dan One-Hadron-Exchange K^-p Interaction Model in Nonrelativistic Energy Region (2021).
Before being inaugurated as a professor, Prof. Imam graduated from FMIPA UI for the Bachelor of Physics program in 1992 and Master of Science in Physics in 1996. In 2003, he obtained the title Dr. rer. nat. from the Faculty of Physics and Astronomy, Ruhr-Universität Bochum, Bochum, Germany. Prof. Imam also served as the Head of the Undergraduate Physics Study Program in 2014–2018; and is currently active as a Member of the Ad Hoc Team for the Evaluation of Physics Curriculum and Physics Education of the Physical Society of Indonesia (PSI) and the Management of the Physical Society of Indonesia (PSI) Jakarta-Banten Branch.
The inauguration ceremony of Prof. Imam was also attended by several invited guests. Among them were Professor of Physics, FMIPA, Bandung Institute of Technology, Prof. Drs. Triyanta, M.S., Ph.D and Prof. Dr. Widayani; Professor of Physics, FMIPA, Jakarta State University, Prof. Dr. Iwan Sugihartono, M.Sc.; Professor Emeritus of the Department of Physics, FMIPA UI, Prof. Dr. Djarwani Soeharso.
