Chuan-Jui Li
A5010265202- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Astrophysical Phenomena and Observations
- Pulsars and Gravitational Waves Research
- Radio Astronomy Observations and Technology
- Stellar, planetary, and galactic studies
- Neutrino Physics Research
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Cryospheric studies and observations
- Superconducting Materials and Applications
- Climate change and permafrost
- Solar and Space Plasma Dynamics
- Galaxies: Formation, Evolution, Phenomena
- High-Energy Particle Collisions Research
- Atmospheric Ozone and Climate
- Particle accelerators and beam dynamics
- Magnetic confinement fusion research
- Geology and Paleoclimatology Research
- Radio Wave Propagation Studies
- Soil Moisture and Remote Sensing
- Winter Sports Injuries and Performance
Institute of Astronomy and Astrophysics, Academia Sinica
2017-2023
University of Chicago
2023
National Taiwan University
2015-2020
The Ohio State University
2019
Ultrahigh energy neutrinos are interesting messenger particles since, if detected, they can transmit exclusive information about ultrahigh processes in the Universe. These particles, with energies above ${10}^{16}\text{ }\text{ }\mathrm{eV}$, interact very rarely. Therefore, detectors that instrument several gigatons of matter needed to discover them. The ARA detector is currently being constructed at South Pole. It designed use Askaryan effect, emission radio waves from neutrino-induced...
The Askaryan Radio Array (ARA) is an ultra-high energy (UHE, $>10^{17}$ eV) neutrino detector designed to observe neutrinos by searching for the radio waves emitted relativistic products of neutrino-nucleon interactions in Antarctic ice. In this paper, we present constraints on diffuse flux between $10^{16}-10^{21}$ eV resulting from a search two complementary analyses, both analyzing four years data (2013-2016) deep stations (A2, A3) operating at that time. We place 90 % CL upper limit all...
Abstract Supergiant shells (SGSs) are the largest interstellar structures in galaxies and inject hot enriched gas into galactic halos. We have studied SGS LMC 1 to determine quantitatively whether stellar energy feedback is adequate power formation of an SGS. The Gaia EDR3 photometric data OB association LH15 inside used construct color–magnitude diagrams, evolutionary tracks isochrones assess masses ages. observed present-day mass function compared with Salpter initial estimate number...
Abstract We have used two methods to search for surviving companions of Type Ia supernova progenitors in three Balmer-dominated remnants the Large Magellanic Cloud: 0519–69.0, 0505–67.9 (DEM L71), and 0548–70.4. In first method, we use Hubble Space Telescope photometric measurements stars construct color–magnitude diagrams (CMDs) compare positions CMDs with those expected from theoretical post-impact evolution main-sequence or helium star companions. No obvious candidates are identified this...
Abstract The geometric structure of supernova remnants (SNR) provides a clue to unveiling the pre-explosion evolution their progenitors. Here we present an X-ray study N103B (0509–68.7), Type Ia SNR in Large Magellanic Cloud, that is known be interacting with dense circumstellar matter (CSM). Applying our novel method for feature extraction deep Chandra observations, have successfully resolved CSM, Fe-rich ejecta, and intermediate-mass element (IME) ejecta components, revealed each spatial...
N103B is a Type Ia supernova remnant (SNR) projected in the outskirts of superbubble around rich cluster NGC 1850 Large Magellanic Cloud (LMC). We have obtained Hα and continuum images with Hubble Space Telescope (HST) high-dispersion spectra 4 m 1.5 telescopes at Cerro Tololo Inter-American Observatory. The HST image exhibits complex system nebular knots inside an incomplete filamentary elliptical shell that opens to east, where X-ray radio emission extends farther out. Electron densities...
We report on analysis of englacial radio-frequency (RF) pulser data received over horizontal baselines 1–5 km, based broadcasts from two sets transmitters deployed to depths up 1500 meters at the South Pole. First, we analyze collected using RF bicone 1400 below ice surface, and frozen into boreholes drilled for IceCube experiment in 2011. Additionally, Dec., 2018, a fat-dipole antenna, fed by one three high-voltage ((1 kV)), fast ((1-5 ns risetime)) signal generators was lowered 1700-m deep...
Abstract We examine a diffuse emission region near the center of SNR 0509−67.5 to determine its nature. Within this we observe point-like source that is bright in near-IR, but not visible B and V bands. consider an line observed at 6766 Å possibilities it Ly α , H [O ii ] λ 3727. spectral energy distribution (SED) source, comprised Hubble Space Telescope I J bands addition Spitzer /IRAC 3.6, 4.5, 5.8, 8 μ m The peak SED consistent with background galaxy z ≈ 0.8 ± 0.2 possible Balmer jump...
Abstract Supergiant shells (SGSs) are the largest interstellar structures where heated and enriched gas flows into host galaxy’s halo. The SGSs in Large Magellanic Cloud (LMC) so close that their stars can be resolved with ground-based telescopes to allow studies of star-formation history. Aiming study star formation history energy budget LMC 4, we have conducted a pilot cluster NGC 2021 OB associations its vicinity near south rim 4. We use Photometric Survey data establish methodology...
Abstract We have used the Dark Energy Camera (DECam) on CTIO Blanco 4 m telescope to perform a new emission-line survey of Large Magellanic Cloud (LMC) using narrowband H α and [S ii ] filters in addition continuum band create pure images. refer this as DeMCELS, distinguish it from earlier Emission-line Survey (MCELS). DeMCELS covers ∼54 deg 2 , encompassing most bright optical disk LMC. With DECam's pixel size only 0.″27, our provides seeing-limited improvement 3–5 times over MCELS is...
Abstract Balmer-dominated shells in supernova remnants (SNRs) are produced by collisionless shocks advancing into a partially neutral medium and most frequently associated with Type Ia supernovae. We have analyzed Hubble Space Telescope (HST) images Very Large (VLT)/Multi-Unit Spectroscopic Explorer (MUSE) or AAT/Wide Field Integral Spectrograph observations of five SNRs containing the LMC: 0509–67.5, 0519–69.0, N103B, DEM L71, 0548–70.4. Contrary to expectations, we find bright...
Abstract The Large Magellanic Cloud (LMC) has ∼60 confirmed supernova remnants (SNRs). Because of the known distance, 50 kpc, SNRs’ angular sizes can be converted to linear sizes, and their X-ray observations used assess luminosities ( L X ). We have critically examined LMC reported in literature determine most plausible sizes. These determined from XMM-Newton are investigate relationship explore environmental evolutionary effects on properties SNRs. Our research provides following three...
We searched for Balmer-dominated Type Ia supernova remnants (SNRs) in M33 by selecting thermal X-ray sources with erg s−1, identifying associated Hα emission features, and checking their [S ii] [O iii] properties. Our search did not find any SNRs M33. This result is puzzling because 2–3 times more massive than the Large Magellanic Cloud (LMC), yet LMC hosts five has none. have considered observational biases; interstellar densities ionization conditions; SN rate expected from star formation...
The Askaryan Radio Array (ARA) is searching for high-energy neutrinos (>10 PeV) from the cosmos using clusters of antennas buried under South Pole ice sheet at a maximum depth 200 m. ARA looking radio Cherenkov emission generated when interact with surrounding medium. array consists 5 stations, each them monitoring an independent portion to maximize detector effective volume. stations use combination vertically polarized (VPol) and horizontally (HPol) antennas, as well in-ice calibration...
The Askaryan Radio Array (ARA) is an in-ice radio detector at the South Pole that targets emission from neutrino-induced particle cascades. Designed to detect neutrinos above 10 PeV, ARA has been taking data for over ten years and includes five independent stations. newest station equipped with a phased array trigger, which lowers trigger threshold compared previous stations thus increases neutrino sensitivity. In this contribution, we discuss analysis results show corresponding improvement...
Abstract The supernova remnant (SNR) 30 Dor B is associated with the H ii region ionized by OB association LH99. complex interstellar environment has made it difficult to study physical structure of this SNR. We have used Hubble Space Telescope α images identify SNR shocks and deep Chandra X-ray observations detect faint diffuse emission. find that hosts three zones very different surface brightnesses nebular kinematics are characteristic SNRs in environments and/or evolutionary stages....
Supergiant shells (SGSs) are the largest interstellar structures where heated and enriched gas flows into host galaxy's halo. The SGSs in Large Magellanic Cloud (LMC) so close that their stars can be resolved with ground-based telescopes to allow studies of star formation history. Aiming study history energy budget LMC 4, we have conducted a pilot cluster NGC 2021 OB associations its vicinity near south rim 4. We use Photometric Survey data establish methodology examine stellar population...
Using data collected by the Askaryan Radio Array (ARA) experiment at South Pole, we have used long-baseline propagation of radio-frequency signals to extract information on index-of-refraction in Polar ice. Owing increasing ice density over upper 150--200 meters, rays are observed along two, nearly parallel paths, one which is direct and a second refracts through an inflection point, with differences both arrival time angle that can be constrain neutrino properties. We also observe...
Abstract 1E 0102.2–7219 (hereafter E0102) is a young supernova remnant (SNR) in the Small Magellanic Cloud. It contains oxygen-rich SN ejecta, possible neutron star (NS), and small amount of fast-moving H-rich ejecta material. These properties are also seen Cas A; it has thus been suggested that E0102 Type IIb SNR, whose progenitor’s hydrogen envelope was stripped off possibly via interactions with companion star. To search for surviving E0102's progenitor, we have used archival Hubble Space...
Abstract We investigate the thermal emission and extinction from dust associated with nearby superluminous supernova (SLSN) 2018bsz. Our dataset has daily cadence simultaneous optical near-infrared coverage up to ~ 100 days, together late time (+1.7 yr) MIR observations. At 230 days after light curve peak SN is not detected in optical, but shows a surprisingly strong excess, r - J > 3 mag K s 5 mag. The evolution of infrared enables us if mid-infrared newly formed inside ejecta,...
Abstract The supernova remnant (SNR) B0532−67.5 in the Large Magellanic Cloud (LMC) was first diagnosed by its nonthermal radio emission, and SNR nature confirmed observation of diffuse X-ray emission; however, no optical shell is detected. OB association LH75, or NGC 2011, projected within boundary this SNR. We have analyzed massive star population around using photometric data to construct color–magnitude diagrams, stellar evolutionary tracks estimate masses, isochrones assess ages. From...