時間：9月17日(四) 13：20 ~ 15：10

題目：A Search for Planet Nine with IRAS and AKARI Data

講者：後藤友嗣 教授

服務單位：國立清華大學 物理學系

地點：本校科學三館1樓 SC157

摘要：The outer solar system is theoretically predicted to harbour an undiscovered planet, often referred to as P9. Simulations suggest that its gravitational influence could explain the unusual clustering of minor bodies in the Kuiper Belt. However, no observational evidence for P9 has been found so far, as its predicted orbit lies far beyond Neptune, where it reflects only a faint amount of Sunlight. This work aims to find P9 candidates by taking advantage of two far-infrared all-sky surveys, which are IRAS and AKARI. The epochs of these two surveys were separated by 23 years, which is large enough to detect the ~3’/year orbital motion of P9. We use a dedicated AKARI Far-Infrared point source list for our P9 search – AKARI Monthly Unconfirmed Source List, which includes sources detected repeatedly only in hours timescale, but not after months. We search for objects that moved slowly between IRAS and AKARI detections given in the catalogues. First, we estimated the expected flux and orbital motion of P9 by assuming its mass, distance, and effective temperature to ensure it can be detected by IRAS and AKARI, then applied the positional and flux selection criteria to narrow down the number of sources from the catalogues. Next, we produced all possible candidate pairs whose angular separations were limited between 42′ and 69.6′, corresponding to the heliocentric distance range of 500 – 700 AU and the mass range of 7 – 17 Earth masses. There are 13 pairs obtained after the selection criteria. After image inspection, we found one good candidate, of which the IRAS source is absent from the same coordinate in the AKARI image after 23 years and vice versa. However, AKARI and IRAS detections are not enough to determine the full orbit of this candidate. This issue leads to the need for follow-up observations, which will determine the Keplerian motion of our candidate.

時間：6月4日(四) 13：20 ~ 15：10

題目：Probing Magnetar Science in the NICER Era

講者：胡欽評 副教授

服務單位：國立彰化師範大學 物理學系

地點：本校科學三館1樓 SC157

時間：4月30日(四) 13：20 ~ 15：10

題目：New Frontiers in Characterizing Exoplanet Atmospheres

講者：蔡尚旻 助研究員

服務單位：中央研究院 天文及天文物理研究所

地點：本校科學三館1樓 SC157

摘要：

Exoplanet science has made remarkable progress. With advancements in high-resolution spectroscopy and the launch of JWST, the field has transitioned from detection to detailed atmospheric characterization.
The diversity of exoplanets presents intriguing puzzles that challenge our theoretical understanding.
In this talk, I will review progress in exoplanet research, with an emphasis on atmospheric characterization. I will highlight some recent JWST observations, including the first evidence of photochemistry on an exoplanet. I will present the enigmatic nature of intermediate-sized planets and share insights from our recent study on temperate sub-Neptunes. I will conclude with key open questions in exoplanet characterization that are within reach of upcoming capabilities.

時間：4月9日(四) 13：20 ~ 15：10

題目：Device-Independent Quantum Rigidity for Secure Global Positioning

講者：郭恩瑞 助理教授

服務單位：國立陽明交通大學 電子物理系

地點：本校科學三館1樓 SC157

摘要：

Device-independent (DI) protocols provide the strongest form of security by removing trust assumptions on quantum devices and relying solely on observed nonlocal correlations and quantum rigidity. In this talk, I will discuss how multipartite Bell nonlocality and self-testing can be leveraged to secure distributed positioning tasks, using a quantum-secured global positioning system (GPS) as a concrete case study.

We consider a protocol based on a five-qubit entangled state shared among four satellites and one ground station, where correct state preparation and measurement behavior are certified solely from Bell inequality violations. I will explain how rigidity guarantees enable device-independent authentication against spoofing and cyberattacks, and discuss practical considerations in the NISQ era, including implementation trade-offs between superconducting and trapped-ion platforms, as well as constraints arising from long-distance photonic distribution.

The emphasis of the talk will be on conveying the core ideas of device-independence and self-testing, with sufficient background to make the discussion accessible to a broad quantum information audience.

For reference, the related paper of mine is available here:
https://link.springer.com/article/10.1140/epjqt/s40507-026-00470-6