Hee-Weon Yi
A5015394228- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Molecular Spectroscopy and Structure
- Astro and Planetary Science
- Atmospheric Ozone and Climate
- Advanced Combustion Engine Technologies
- Spectroscopy and Laser Applications
- Plant biochemistry and biosynthesis
- Astronomy and Astrophysical Research
- Effects of Environmental Stressors on Livestock
- Adipose Tissue and Metabolism
- Microbial Natural Products and Biosynthesis
- Ruminant Nutrition and Digestive Physiology
- Satellite Communication Systems
- Mobile Agent-Based Network Management
- Carbohydrate Chemistry and Synthesis
- Phase Equilibria and Thermodynamics
- Advanced Optical Network Technologies
- Computational Drug Discovery Methods
- Agriculture and Biological Studies
- Space Exploration and Technology
- Galaxies: Formation, Evolution, Phenomena
- Atomic and Molecular Physics
- Dietary Effects on Health
Jiangnan University
2024
Korea Astronomy and Space Science Institute
2022-2024
Jiangxi Normal University
2024
Anhui Agricultural University
2024
Beijing University of Posts and Telecommunications
2024
Kyung Hee University
2016-2022
Abstract Protostellar outflows and jets are almost ubiquitous characteristics during the mass accretion phase encode history of stellar accretion, complex organic molecule (COM) formation, planet formation. Episodic likely connected to episodic through disk. Despite importance, studies on ejection links have not been done yet in a systematic fashion using high-sensitivity high-resolution observations. To explore mechanisms chronologies events, we investigated 39 fields containing protostars...
The "ATOMS," standing for {\it ALMA Three-millimeter Observations of Massive Star-forming regions}, survey has observed 146 active star forming regions with Band 3, aiming to systematically investigate the spatial distribution various dense gas tracers in a large sample Galactic massive clumps, study roles stellar feedback formation, and characterize filamentary structures inside clumps. In this work, observations, data analysis, example science "ATOMS" are presented, using case G9.62+0.19...
The low dust temperatures (<14 K) of Planck Galactic cold clumps (PGCCs) make them ideal targets to probe the initial conditions and very early phase star formation. "TOP-SCOPE" is a joint survey program targeting ∼2000 PGCCs in J = 1–0 transitions CO isotopologues ∼1000 850 μm continuum emission. objective surveys (SMT 10 m, KVN 21 NRO 45 m) statistically study occurring during formation evolution molecular clouds, across wide range environments. observations, data analysis, example science...
We have identified 453 compact dense cores in 3 mm continuum emission maps the ATOMS (ALMA Three-millimeter Observations of Massive Star-forming regions) survey, and compiled three catalogues high-mass star forming cores. One catalogue, referred to as H/UC-HII includes 89 that enshroud hyper/ultra (H/UC) HII regions characterized by associated H40alpha emission. A second pure s-cHMC, 32 candidate Hot Molecular Cores (HMCs) showing rich spectra (N>20lines) complex organic molecules (COMs) but...
Magnetic field is one of the key agents that play a crucial role in shaping molecular clouds and regulating star formation, yet complete information on magnetic not well constrained due to limitations observations. We study massive infrared dark cloud G035.39-00.33 from dust continuum polarization observations at 850 $\micron$ with SCUBA-2/POL-2 JCMT. The tends be perpendicular densest part main filament (F$_{M}$), whereas it has less defined relative orientation rest structure, where...
ABSTRACT We are performing a series of observations with ground-based telescopes toward Planck Galactic cold clumps (PGCCs) in the λ Orionis complex order to systematically investigate effects stellar feedback. In particular case PGCC G192.32–11.88, we discovered an extremely young Class 0 protostellar object (G192N) and proto-brown dwarf candidate (G192S). G192N G192S located gravitationally bound bright-rimmed clump. The velocity temperature gradients seen line emission CO isotopologues...
Based on the 850 $\mu$m dust continuum data from SCUBA-2 at James Clerk Maxwell Telescope (JCMT), we compare overall properties of Planck Galactic Cold Clumps (PGCCs) in $\lambda$ Orionis cloud to those PGCCs Orion A and B clouds. The clouds are well known active star-forming regions, while has a different environment as consequence interaction with prominent OB association giant Hii region. have higher temperatures ($Td=16.13\pm0.15$ K) lower values emissivity spectral index ($...
We report studies of the relationships between total bolometric luminosity ($L_{\rm bol}$ or $L_{\rm TIR}$) and molecular line luminosities $J=1-0$ transitions H$^{13}$CN, H$^{13}$CO$^+$, HCN, HCO$^+$ with data obtained from ACA observations in "ATOMS" survey 146 active Galactic star forming regions. The correlations $L'_{\rm mol}$ four all appear to be approximately linear. Line emission isotopologues shows as large scatters bol}$-$L'_{\rm relations their main emission. log($L_{\rm...
Analysis of all-sky Planck submillimetre observations and the IRAS 100um data has led to detection a population Galactic cold clumps. The clumps can be used study star formation dust properties in wide range environments. Our aim is measure spectral energy distribution (SED) variations as function spatial scale wavelength. We examine SEDs at large scales using IRAS, Planck, Herschel data. At smaller scales, we compare with JCMT/SCUBA-2 850um maps that are filtered SCUBA-2 pipeline. Clumps...
Abstract We present the results of a single-pointing survey 207 dense cores embedded in Planck Galactic Cold Clumps distributed five different environments ( λ Orionis, Orion A, B, plane, and high latitudes) to identify on verge star formation for study initial conditions formation. observed these eight molecular lines at 76–94 GHz using Nobeyama 45 m telescope. find that early-type molecules (e.g., CCS) have low detection rates late-type N 2 H + c-C 3 ) deuterated D DNC) rates, suggesting...
Abstract Protostellar outflows and jets play a vital role in star formation as they carry away excess angular momentum from the inner disk surface, allowing material to be transferred toward central protostar. Theoretically, low-velocity poorly collimated appear beginning of collapse at first hydrostatic core (FHSC) stage. With growing protostellar mass, high-density are launched, entraining an outflow infalling envelope. Until now, molecular have been observed high velocity (≳100 km s −1 )...
Stellar kinematics is a powerful tool for understanding the formation process of stellar associations. Here, we present kinematic study young population in Rosette nebula using recent Gaia data and high-resolution spectra. We first isolate member candidates published mid-infrared photometric list X-ray sources. A total 403 stars with similar parallaxes proper motions are finally selected as members. The spatial distribution members shows that this star-forming region highly substructured....
Massive stars have a strong impact on their local environments. However, how stellar feedback regulates star formation is still under debate. In this context, we studied the chemical properties of 80 dense cores in Orion molecular cloud complex composed A (39 cores), B (26 and lambda Orionis (15 cores) clouds using multiple line data taken with Korean Very Long Baseline Interferometry Network (KVN) 21-m telescopes. The has an H ii bubble surrounding O-type Ori, hence it exposed to...
We present the results of on-the-fly mapping observations 44 fields containing 107 SCUBA-2 cores in emission lines molecules, N$_2$H$^+$, HC$_3$N, and CCS at 82$-$94 GHz using Nobeyama 45-m telescope. This study aimed investigating physical properties that show high deuterium fractions might be close to onset star formation. found distributions N$_2$H$^+$ HC$_3$N line emissions are approximately similar 850-$\mu$m dust continuum emission, whereas is often undetected or distributed a clumpy...
In this study, 36 cores (30 starless and 6 protostellar) identified in Orion were surveyed to search for inward motions. We used the Nobeyama 45 m radio telescope, mapped $J = 1\rightarrow0$ transitions of HCO$^+$, H$^{13}$CO$^+$, N$_2$H$^+$, HNC, HN$^{13}$C. The asymmetry parameter $\delta V$, which was ratio difference between HCO$^+$ H$^{13}$CO$^+$ peak velocities line width, biased toward negative values, suggesting that motions more dominant than outward Three (10% all surveyed) as with...
Abstract Gas at high Galactic latitude is a relatively little noticed component of the interstellar medium. In an effort to address this, 41 Planck Cold Clumps (HGal; ∣ b > 25°) were observed in 12 CO, 13 and C 18 O J = 1−0 lines, using Purple Mountain Observatory 13.7 m telescope. CO (1−0) emission was detected all clumps, while only seen 16 clumps. The highest average latitudes are 71.°4 37.°8, respectively. Fifty-one velocity components obtained, then each identified as single clump....
Protostellar outflows and jets are almost ubiquitous characteristics during the mass accretion phase, encode history of stellar accretion, complex-organic molecule (COM) formation, planet formation. Episodic likely connected to episodic through disk. Despite importance, there is a lack studies statistically significant sample protostars via high-sensitivity high-resolution observations. To explore mechanisms chronologies events, we investigated 42 fields containing with ALMA observations CO,...
Heat stress (HS) has become a common stressor, owing to the increasing frequency of extreme high-temperature weather triggered by global warming, which seriously affected reproductive capacity important livestock such as sheep. However, little is known about whether HS reduces sperm motility inducing circadian rhythm disorders in rumen microorganisms and metabolites In this study, year-round reproduction two-year-old Hu rams was selected, samples were collected May July 2022 at average...
Sleep deprivation (SD) disrupts circadian rhythms; however, its effects on SD and the mechanisms involved require further investigation. Previous studies were mainly conducted rodents, such as mice, with few liver of large diurnal animals, sheep. In this study, we used a Tibetan sheep model for first time to investigate by exposing (
A chemical synthetic strategy toward chartreusin derivatives has been established for the first time, facilitating detailed bioactivity investigations.