To explore the mechanism responsible for the generation of observed matter-antimatter asymmetry in the Universe, the research on fundamental symmetry violations and various fundamental interactions using the laser cooled and trapped atoms is being promoted. The understanding of how the symmetry between the matter and antimatter was broken during the evolution of the early universe requires laboratory experiments which search for symmetry violations in the elementary particles such as quarks and leptons; one such phenomenon of our interest is the intrinsic electric dipole moment (EDM) of either elementary or composite systems. In our laboratory, we produce extremely heavy radioactive elements from nuclear fusion reactions. We trap the heavy unstable atoms and cool them using intense laser beams in order to realize the extreme quantum state of matter such as the Bose-Einstein condensate (BEC), which will be used later for the detection of the EDM signal. The construction of a facility containing high density of laser cooled radioactive atoms is in progress, and it serves as a center for carrying out several studies on fundamental symmetries and their violations including the EDMs which arise due to the CP (combined charge parity symmetry) violating interactions between quarks and leptons and between quarks themselves. Furthermore, the non-zero observation of EDMs provide the direct and conclusive signatures of the violation of time-reversal symmetry. The study of EDMs also paves a way for the continuing quest for the ultimate theory of the Universe and it has a great potential in uncovering many mysteries which have been puzzling the mankind for ages such as the very survival of ourselves amidst many cosmic catastrophes such as a complete annihilation of matter and antimatter in the Universe. Another challenge being pursued in our lab is the realization of extreme quantum state known as the alpha particle condensate, in which the alpha particles being Bosons condense into the same exotic excited state of the nucleus. This is reminiscent with the BEC state of the atoms but it is in nuclear matter. The structure of this exotic state is being studied using the high quality ion beam and it has a significant bearing on the nucleosynthesis. Using these extreme quantum states of matter at the low-energy scales we study the high-energy physics related to the phenomena which are thought to have happened in various epochs in the very early Universe.
Fundamental Symmetry / Fundamental Interaction, Nuclear force, CP violation, Super symmetry, Laser cooled radioactive atom, Bose Einstein Condensation, Alpha particle condensation, Cluster structure
Professor Atsuki Terakawa
Research Professor/Visiting Professor Yasuhiro SAKEMI
- Experimental Nuclear Physics