Chuan-Jui Li (李傳睿)

Projects

中文

Type Ia Supernova Remnants

SNR 0509-68.7 (N103B)

Credit: NASA, ESA and Y.-H. Chu, Judy Schmidt/CXC/SAO

Physical Structures of the Type Ia Supernova Remnant N103B

Li, C.-J., Chu, Y.-H., Gruendl, R. A., et al., The Astrophysical Journal, 836, 85 (2017)

N103B is a young Type Ia supernova remnant (SNR Ia) in the Large Magellanic Cloud (LMC). Using Hubble Space Telescope images of N103B, I constructed color-magnitude diagrams of the underlying stellar population and compared the locations of stars in the color-magnitude diagrams with the models of surviving companions.

Over the past decades, no surviving companion has been unambiguously identified within SNRs Ia in the Milky Way Galaxy. In this work, I photometrically identified a surviving companion candidate within a SNR Ia outside the Milky Way Galaxy for the first time!

The Physical Society of Taiwan (TPS) Excellent Postgraduates Student Thesis Award 2018

(台灣物理學會研究生優良論文獎)

Search for Surviving Companions of Progenitors of Young LMC SN Ia Remnants

Li, C.-J., Kerzendorf, W. E., Chu, Y.-H., et al., The Astrophysical Journal, 886, 99 (2019)

Advancing forward from previous work, I used the Very Large Telescope (VLT) Multi-Unit Spectroscopic Explorer (MUSE) observations to carry out spectroscopic analyses of stars within SNRs Ia in the LMC.

In this work, I found more candidates of surviving companions within SNRs Ia. In astronomy, it has been said that a picture is worth a thousand words but a spectrum is worth a thousand images. It is the first time that candidates of surviving companions of SN Ia progenitors are spectroscopically identified near the centers of SNRs Ia outside the Milky Way Galaxy; furthermore, I found that 20%– 60% of young LMC Type Ia SNRs may have single-degenerate origins, significantly higher than the 20% that people previously suggested in the Milky Way Galaxy.

Ministry of Science and Technology (MoST) Postdoctoral Fellow Academic Research Award 2020

(科技部博士後研究人員學術研究獎)

SNR 0519-69.0

Credit: X-ray: NASA/CXC/Rutgers/J.Hughes; Optical: NASA/STScI

Referee: ``This work is a significant step in improving the knowledge of surviving companions of SNe Ia explosions. Due to the limited number of supernova remnants explored for the determination of nature of SNe Ia, the work presented here exploring SNe Ia in the LMC expands substantially the knowledge in this field of research.''

SNR 0509-67.5

Credit: Optical: NASA/ESA/Hubble Heritage Team (STScI/AURA) X-ray: NASA/CXC/SAO/J.Hughes et al

SNR 0505-67.9 (DEM L71)

Credit: X-ray: NASA/CXC/Rutgers/J.Hughes et al; Optical: ESA/Hubble & NASA and Y. H. Chu Judy Schmidt

SNR 0548-70.4

Credit: Y. H. Chu

Forbidden Line Emission from Type Ia Supernova Remnants Containing Balmer-Dominated Shells

Li, C.-J., Chu, Y.-H., John C. Raymond, et al., The Astrophysical Journal, 923,141 (2021)

Young SNRs Ia show filamentary shells with optical spectra dominated by Balmer lines without forbidden-line counterparts; however, I was pleasantly surprised to find that bright forbidden line emission from dense circumstellar medium in 4 out of 5 young LMC SNRs Ia containing Balmer-dominated shells. Dense forbidden-line-emitting circumstellar medium was discovered in 0519-69.0, DEM L71, and 0548-70.4 for the first time!

It indicates that 80% of these five young LMC SNRs Ia may originate from single-degenerate progenitors, consistent with my previous findings based on the search for surviving companions in 2017 and 2019. In this work, the proportion of single-degenerate to double-degenerate origins of young LMC SNRs Ia is firstly given by searching for the circumstellar medium. Furthermore, physical property variations of the circumstellar medium in the SNRs appear to reflect an evolutionary effect. It indicates that the presence of circumstellar medium in SNRs Ia could be more prevalent than people previously thought in the Milky Way.

ASIAA January Science Highlights 2022

(中研院天文所一月研究成果發表 2022)

HST Hα and VLT MUSE Hα, [O III], [Fe XIV], [O I], and [S II] images of SNR 0509–67.5. No dense circumstellar medium inside the Hα shell was detected, consistent with our expectation for its confirmed double-degenerate origin.

HST Hα and VLT MUSE Hα, [O III], [Fe XIV], [O I], and [S II] images of N103B. Dense forbidden-line-emitting circumstellar medium is detected in each image. Its SN progenitor is likely a single-degenerate origin.

Searching For Surviving Companion In The Young SMC Supernova Remnant 1E 0102.2-7219

Li, C.-J., Seitenzahl, I. R., Ishioka, R., Chu, Y.-H., et al., The Astrophysical Journal, 915, 20 (2021)

1E 0102.2–7219 (hereafter E0102) is a young supernova remnant (SNR) in the Small Magellanic Cloud (SMC). It contains oxygen-rich SN ejecta, a possible neutron star (NS), and a small amount of fast-moving H-rich ejecta material. These properties are also seen in the galactic Type IIb SNR Cas A, it has thus been suggested that E0102 is also a Type IIb SNR.

The discovery of the fast-moving H-rich material implies that the SN progenitor‘s hydrogen envelope was stripped off possibly via interactions with a companion star. In the Milky Way, searches for companions of SN progenitors in the Cas A have not found a surviving companion. It is thus worthwhile searching for a surviving companion of E0102’s SN progenitor outside the Milky Way.