Il-Gyo Jeong
A5066719696- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- Atmospheric Ozone and Climate
- Solar and Space Plasma Dynamics
- Electrowetting and Microfluidic Technologies
- Microfluidic and Bio-sensing Technologies
- Astrophysical Phenomena and Observations
- Micro and Nano Robotics
- Radio Astronomy Observations and Technology
- Astronomical Observations and Instrumentation
- Microfluidic and Capillary Electrophoresis Applications
- Cultural and Historical Studies
- Galaxies: Formation, Evolution, Phenomena
- Astronomy and Astrophysical Research
- Superconducting Materials and Applications
- Ferroelectric and Negative Capacitance Devices
- Nuclear physics research studies
- High-pressure geophysics and materials
- Ionosphere and magnetosphere dynamics
- Innovative Microfluidic and Catalytic Techniques Innovation
- Magnetic and Electromagnetic Effects
- Fault Detection and Control Systems
Kyungpook National University
2021-2024
Korea Astronomy and Space Science Institute
2016-2024
Seoul National University
2009-2016
Chungnam National University
2012
We present the first results from B-fields In STar-forming Region Observations (BISTRO) survey, using Sub-millimetre Common-User Bolometer Array 2 (SCUBA-2) camera, with its associated polarimeter (POL-2), on James Clerk Maxwell Telescope (JCMT) in Hawaii. discuss survey's aims and objectives. describe rationale behind questions which survey will aim to answer. The most important of these is role magnetic fields star formation process scale individual filaments cores dense regions. data...
Context. Molecular filaments and hubs have received special attention recently thanks to new studies showing their key role in star formation. While the (column) density velocity structures of both been carefully studied, magnetic field (B-field) properties yet be characterized. Consequently, B-fields formation evolution hub-filament systems is not well constrained. Aims. We aim understand B-field its interplay with turbulence gravity dynamical NGC 6334 filament network that harbours...
We present the results of dust emission polarization measurements Ophiuchus-B (Oph-B) carried out using Submillimetre Common-User Bolometer Array 2 (SCUBA-2) camera with its associated polarimeter (POL-2) on James Clerk Maxwell Telescope (JCMT) in Hawaii. This work is part B-fields In Star-forming Region Observations (BISTRO) survey initiated to understand role magnetic fields star formation for nearby star-forming molecular clouds. a first look at geometry and strength Oph-B. The field...
Abstract We present 850 μ m imaging polarimetry data of the ρ Oph-A core taken with Submillimeter Common-User Bolometer Array-2 (SCUBA-2) and its polarimeter (POL-2) as part our ongoing survey project, <?CDATA ${\boldsymbol{B}}$?> -fields In STar forming RegiOns (BISTRO). The polarization vectors are used to identify orientation magnetic field projected on plane sky at a resolution 0.01 pc. 10 subregions distinct fractions angles in 0.2 pc core; some them can be coherent structure Oph...
We present new observations of the active star-formation region NGC 1333 in Perseus molecular cloud complex from James Clerk Maxwell Telescope B-Fields In Star-forming Region Observations (BISTRO) survey with POL-2 instrument. The BISTRO data cover entire (~1.5 pc x 2 pc) at 0.02 resolution and spatially resolve polarized emission individual filamentary structures for first time. inferred magnetic field structure is as a whole, each filament aligned different position angles relative to...
We report 850~$\mu$m dust polarization observations of a low-mass ($\sim$12 $M_{\odot}$) starless core in the $\rho$ Ophiuchus cloud, C, made with POL-2 instrument on James Clerk Maxwell Telescope (JCMT) as part JCMT B-fields In STar-forming Region Observations (BISTRO) survey. detect an ordered magnetic field projected plane sky core. The across $\sim$0.1~pc shows predominant northeast-southwest orientation centering between $\sim$40$^\circ$ to $\sim$100$^\circ$, indicating that is well...
Abstract We present 850 μ m polarimetric observations toward the Serpens Main molecular cloud obtained using POL-2 polarimeter on James Clerk Maxwell Telescope as part of B-fields In STar-forming Region Observations survey. These probe magnetic field morphology about 6000 au scales, which consists cores and six filaments with different physical properties such density star formation activity. Using histogram relative orientation (HRO) technique, we find that fields are parallel to in...
Abstract We report 850 μ m continuum polarization observations toward the filamentary high-mass star-forming region NGC 2264, taken as part of B -fields In STar forming Regions Observations large program on James Clerk Maxwell Telescope. These data reveal a well-structured nonuniform magnetic field in 2264C and 2264D regions with prevailing orientation around 30° from north to east. Field strength estimates virial analysis major clumps indicate that is globally dominated by gravity, while...
Abstract We have obtained sensitive dust continuum polarization observations at 850 μ m in the B213 region of Taurus using POL-2 on SCUBA-2 James Clerk Maxwell Telescope as part B -fields STar-forming Region Observations (BISTRO) survey. These allow us to probe magnetic field ( -field) high spatial resolution (∼2000 au or ∼0.01 pc 140 pc) two protostellar cores (K04166 and K04169) one prestellar core (Miz-8b) that lie within filament. Using Davis–Chandrasekhar–Fermi method, we estimate...
Abstract We report the first high spatial resolution measurement of magnetic fields surrounding LkH α 101, part Auriga–California molecular cloud. The observations were taken with POL-2 polarimeter on James Clerk Maxwell Telescope within framework B-fields In Star-forming Region Observations (BISTRO) survey. Observed polarization thermal dust emission at 850 μ m is found to be mostly associated redshifted gas component field displays a relatively complex morphology. Two variants...
We study the HII regions associated with NGC 6334 molecular cloud observed in sub-millimeter and taken as part of B-fields In STar-forming Region Observations (BISTRO) Survey. particular, we investigate polarization patterns magnetic field morphologies these regions. Through pattern pressure calculation analyses, several bubbles indicate that gas lines have been pushed away from bubble, toward an almost tangential (to bubble) morphology. densest 6334, where morphology is similar to...
We have investigated the molecular environment of semicircular composite supernova remnant (SNR) 3C 396 and performed a Chandra spatially resolved thermal X-ray spectroscopic study this young SNR. With our CO millimeter observations, we find that clouds (MCs) at VLSR∼ 84 km s−1 can better explain multiwavelength properties than VLSR = 67–72 MCs are suggested by Lee et al. At around s−1, western boundary SNR is perfectly confined wall. The emission fades out from west to east, indicating...
The young composite supernova remnant (SNR) Kesteven 75 (Kes 75), with a pulsar wind nebula at its center, has an unusual morphology bright southern half-shell structure in multiwavelengths. distance to Kes long been uncertain. Aiming address these issues, we have made millimeter spectroscopic observations of the molecular gas toward remnant. VLSR∼ 83–96 km s−1 clouds (MCs) are found overlap large northwestern region and suggested be located front SNR along line sight. Also area, VLSR =...
ABSTRACT Recent high-resolution infrared space missions have revealed supernova remnants (SNRs) of diverse morphology in (IR) dust emission that are often very different from their X-ray appearance. The observed range infrared-to-X-ray (IRX) flux ratios SNRs is also wide. For a sample 20 Galactic SNRs, we obtain IR and properties investigate the physical causes for such large differences. We find IRX ( <?CDATA ${R}_{{\rm{IRX,obs}}}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"...
We present 850 $\mu$m dust polarization observations of the massive DR21 filament from B-fields In STar-forming Region Observations (BISTRO) survey, using POL-2 polarimeter and SCUBA-2 camera on James Clerk Maxwell Telescope. detect ordered magnetic fields perpendicular to parsec-scale ridge main filament. sub-filaments, are mainly parallel filamentary structures smoothly connect compare Planck study field 0.1--10 pc scales. The revealed in data well aligned with those data, indicating a...
We present and analyze observations of polarized dust emission at 850 $\mu$m towards the central 1 pc $\times$ hub-filament structure Monoceros R2 (Mon R2). The data are obtained with SCUBA-2/POL-2 on James Clerk Maxwell Telescope (JCMT) as part BISTRO (B-fields in Star-forming Region Observations) survey. orientations magnetic field follow spiral Mon R2, which well-described by an axisymmetric model. estimate turbulent component using angle difference between our best-fit model underlying...
Abstract We present observations of polarized dust emission at 850 μ m from the L43 molecular cloud, which sits in Ophiuchus cloud complex. The data were taken using SCUBA-2/POL-2 on James Clerk Maxwell Telescope as a part BISTRO large program. is dense ( <?CDATA ${N}_{{{\rm{H}}}_{2}}\sim {10}^{22}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msub> <mml:mrow> <mml:mi>N</mml:mi> </mml:mrow> <mml:mi mathvariant="normal">H</mml:mi> <mml:mn>2</mml:mn>...
Abstract We present the 850 μ m polarization observations toward IC 5146 filamentary cloud taken using Submillimetre Common-User Bolometer Array 2 (SCUBA-2) and its associated polarimeter (POL-2), mounted on James Clerk Maxwell Telescope, as part of B -fields In STar forming Regions Observations. This work is aimed at revealing magnetic field morphology within a core-scale (≲1.0 pc) hub-filament structure (HFS) located end parsec-scale filament. To investigate whether observed traces in HFS,...
We present the results of simultaneous 450 $\mu$m and 850 polarization observations toward massive star forming region NGC 2071IR, a target BISTRO (B-fields in Star-Forming Region Observations) Survey, using POL-2 polarimeter SCUBA-2 camera mounted on James Clerk Maxwell Telescope. find pinched magnetic field morphology central dense core region, which could be due to rotating toroidal disk-like structure bipolar outflow originating from young stellar object, IRS 3. Using modified...
We present the POL-2 850 $\mu$m linear polarization map of Barnard 1 clump in Perseus molecular cloud complex from B-fields In STar-forming Region Observations (BISTRO) survey at James Clerk Maxwell Telescope. find a trend decreasing fraction as function total intensity, which we link to depolarization effects towards higher density regions cloud. then use data infer plane-of-sky orientation large-scale magnetic field 1. This runs North-South across most cloud, with exception B1-c where it...
In this study, we fabricate an integrated microfluidic chip with a planar Hall effect (PHE) sensor for single magnetic bead detection. The PHE was constructed junction size of <TEX>$10{\mu}m{\times}10{\mu}m$</TEX> using trilayer structure Ta(3 nm)/NiFe(10 nm)/Cu(1.2 nm)/IrMn(10 nm)/Ta(3 nm). sensitivity the 19.86 <TEX>${\mu}V/Oe$</TEX>. A diameter 8.18 <TEX>${\mu}m$</TEX> beads used, which saturation magnetization ~2.1 emu/g. susceptibility <TEX>${\chi}$</TEX> these calculated to be ~0.14....
Abstract We present BISTRO Survey 850 μ m dust emission polarization observations of the L1495A-B10 region Taurus molecular cloud, taken at James Clerk Maxwell Telescope (JCMT). observe a roughly triangular network dense filaments. detect nine starless cores embedded within these filaments in polarization, finding that plane-of-sky orientation core-scale magnetic field lies perpendicular to almost all cases. also find large-scale measured by Planck is not correlated with any core or filament...
We have designed, fabricated and tested an integrated microfluidic chip with a Planar Hall Effect (PHE) sensor. The sensor was constructed by sequentially sputtering Ta/NiFe/Cu/NiFe/IrMn/Ta onto glass. channel poly(dimethylsiloxane) (PDMS) using soft lithography. Magnetic nanoparticles suspended in hexadecane were used as ferrofluid, of which the saturation magnetisation 3.4 emu/cc. Droplets ferrofluid generated T-junction after hydrophilic modification PDMS. size interval droplets regulated...