Division of Science, NAOJ

TBD

================= May. 7 Wed ================= Campus: Mitaka Seminar: NAOJ Science Colloquium Date and time: 2025 May 7 (Wed.), 15:30-16:30 JST Place: The large seminar room  / Zoom (hybrid) Speaker: Masafumi Niwano Affiliation: NAOJ ADC/DoS Title: Study of the relationship between circumstellar disc evolution and Be donor activities in BeXBs Abstract: The mechanism of X-ray outbursts in Be X-ray binaries remains a mystery, and understanding their circumstellar discs is crucial for a solution of the mass-transfer problem. In particular, it is important to identify the Be star activities (e.g. pulsations) that cause mass ejection and, hence, disc formation. Therefore, we investigated the relationship between optical flux oscillations and the infrared (IR) […]

================= Apr. 23 Wed ================= Campus: Mitaka Seminar: NAOJ Science Colloquium Date and time: 2025 April 23 (Wed.), 15:30-16:30 JST Place: The insei seminar room of Subaru Building / Zoom (hybrid) Speaker: Kazunori Kohri Affiliation: DoS, NAOJ Title: Is Stephen Hawking's evaporation of black holes wrong? - Black Hole as a new candidate for dark matter - Abstract: Last year, Prof. Gia Dvali, an expert in quantum gravity theory, criticized Stephen Hawking's proposal for calculating the evaporation of black holes due to Hawking radiation, insisting that the initial conditions assumed were not appropriate, and if he added the back reaction (the Memory Burden Effect) from the entropy of Hawking radiation […]