Re: NCTS Astrophysics Student Lunch Seminars [July to December 2025]
Dear colleagues,
We will have our monthly NCTS Astrophysics Student Lunch Seminars next Friday, 9/26, from 12pm in the 4F lecture room in the Cosmology Hall. Talk details are appended below. You can sign up for lunch boxes here:
https://forms.gle/ABb2VD3hd2vxTYqAA
Please come and support our students.
Cheers, Min-Kai
*1. From Simulations to Spectra: Investigating AGN Wind-Disk Interactions and Asymmetric Galactic Outflows *
Chiung-Yin Chan (NTHU, supervisor: Karen Yang)
We use 3D special relativistic hydrodynamic (SRHD) simulations to study AGN-driven winds in a disk galaxy. Our results reveal an early-stage (t ~ 0.1 Myr) asymmetry in bubble formation, with one bubble reaching velocities up to 2000 km/s while the other remains underdeveloped due to interactions with the clumpy disk. This aligns with JWST observations of NGC 7469, which show a circumnuclear starburst ring and one-sided high-velocity outflows. To explore observational signatures, we generate mock spectra using TRIDENT, finding that the asymmetry is detectable in the [NeV] line at optical wavelengths, as TRIDENT produces spectra comparable to HST rather than JWST. Phase diagrams suggest that matching observed emission requires the disk density in our simulations to be at least an order of magnitude lower. These findings provide insight into AGN wind-disk interactions and offer a potential explanation for the asymmetric outflows in NGC 7469.
2. Irradiation Bias in Dynamical Mass Determination
Huan-Ping Chao (NCKU, supervisor: Kwan-Lok Li)
We have developed a Python tool to simulate the optical observations of tidally locked companions in compact binary systems, based on the Roche potential and the Göttingen spectral library. The tool generates phase-resolved spectra from arbitrary viewing angles. With these simulations, we investigate the impact of irradiation on the observed center of light and assess the resulting biases in dynamical mass measurements of the compact primary. For a system analogous to PSR J0952−0607, our results show that irradiation shifts the center of light inward, reducing its effective radius by about 6.3% compared to a non-irradiated model. This bias indicates that fitting observations of irradiated systems with non-irradiated models systematically underestimates the mass of the compact primary. Min-Kai Lin mklin@asiaa.sinica.edu.tw於 2025年7月14日 週一，下午12:41寫道：
Dear colleagues,
The NCTS Astrophysics group is resuming our monthly student seminar series. These provide opportunities for our domestic students to share their work and practice giving live talks. The schedule for the rest of the year is appended below. Seminars begin at 12pm in the 4F lecture room in the Cosmology Hall on the NTU campus. Talks are open to all.
Sign up links for lunch boxes will become available from the NCTS seminar list a week before the talks:
https://phys.ncts.ntu.edu.tw/en/act/Seminars/seminars_TG2
Cheers, Min-Kai
Date Speaker 1 Affiliation Supervisor Speaker 2 Affiliation Supervisor 2025/7/24 Pon-Yin Wang TKU Hsi-An Pan 2025/8/22 Tsung-Han Chuang NTNU Yueh-Ning Lee 2025/9/26 Chiung-Yin Chang NTHU Hsiang-Yi Karen Yang Huan-Ping Chao NCKU Kwan-Lok Li 2025/10/31 Yi-Yang Lee NTHU Hsiang-Yi Karen Yang Prangsutip Cherdwongsung NTHU Ing-Guey Jiang 2025/11/28 Yu-Xuan Nancy Lin NYCU Shih-Ping Lai Tz-En Gau NTU Chia-Yu Hu 2025/12/26 Szu-Ting Chen NTHU Shin-Ping Lai Afif Ismail NTNU Hung-Yi Pu