Junhao Liu
A5100725200- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Solar and Space Plasma Dynamics
- Atmospheric Ozone and Climate
- Galaxies: Formation, Evolution, Phenomena
- Astrophysical Phenomena and Observations
- Cardiac Imaging and Diagnostics
- Molecular Spectroscopy and Structure
- Advanced Combustion Engine Technologies
- Acute Myocardial Infarction Research
- Atomic and Subatomic Physics Research
- Ionosphere and magnetosphere dynamics
- Molecular spectroscopy and chirality
- Magnetic and Electromagnetic Effects
- Spectroscopy and Laser Applications
- High-pressure geophysics and materials
- Adaptive optics and wavefront sensing
- Geomagnetism and Paleomagnetism Studies
- Coronary Interventions and Diagnostics
- Advanced NMR Techniques and Applications
- Data Quality and Management
- Ocean Waves and Remote Sensing
- Gout, Hyperuricemia, Uric Acid
- Heart Failure Treatment and Management
East Asian Observatory
2021-2024
National Astronomical Observatory of Japan
2023-2024
National Institutes of Natural Sciences
2024
Chinese Academy of Medical Sciences & Peking Union Medical College
2018-2023
Nanjing University
2017-2023
University of Toronto
2023
Center for Astrophysics Harvard & Smithsonian
2019-2022
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...
The Davis-Chandrasekhar-Fermi (DCF) method provides an indirect way to estimate the magnetic field strength from statistics of orientations. We compile all previous DCF estimations polarized dust emission observations and re-calculate selected samples with new correction factors in Liu et al. (2021). find scales volume density as $B \propto n^{0.57}$. However, estimated power-law index observed $B-n$ relation has large uncertainties may not be comparable theoretical models. A clear trend...
Abstract Magnetic fields of molecular clouds in the central zone (CMZ) have been relatively under-observed at sub-parsec resolution. Here, we report JCMT/POL2 observations polarized dust emission CMZ, which reveal magnetic field structures dense gas ∼0.5 pc The 11 our sample include two western part CMZ (Sgr C and a farside cloud candidate), four around Galactic longitude 0 (the 50 km s −1 cloud, CO 0.02−0.02, Stone , Sticks Straw among Three Little Pigs), five along Dust Ridge...
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...
Risk assessment and treatment stratification for three-vessel disease (3VD) remain challenging. N-terminal pro-B-type natriuretic peptide (NT-proBNP) is an established biomarker prognostication in heart failure. The present study aimed to evaluate the prognostic value of NT-proBNP beyond SYNTAX score II (SSII), its association with long-term outcome after three strategies [percutaneous coronary intervention (PCI), artery bypass grafting (CABG), medical therapy (MT)] a cohort patients 3VD.A...
Abstract We present the B -fields mapped in IRDC G34.43+0.24 using 850 μ m polarized dust emission observed with POL-2 instrument at James Clerk Maxwell telescope. examine magnetic field geometries and strengths northern, central, southern regions of filament. The overall geometry is ordered aligned closely perpendicular to filament’s main axis, particularly containing central clumps MM1 MM2, whereas MM3 north has orientations its major axis. are uniform large (POL-2 14″ SHARP 10″) small...
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 Theoretical and numerical works indicate that a strong magnetic field should suppress fragmentation in dense cores. However, this has never been tested observationally relatively large sample of fragmenting massive Here, we use the polarization data obtained Submillimeter Array Legacy Survey Zhang et al. to build 18 cores where both properties are studied uniform way. We measured level, N mm , within view common all regions ∼0.15 pc, with mass sensitivity ∼0.5 M ☉ spatial resolution...
The Davis-Chandrasekhar-Fermi (DCF) method is widely used to indirectly estimate the magnetic field strength from plane-of-sky orientation. In this work, we present a set of 3D MHD simulations and synthetic polarization images using radiative transfer clustered massive star-forming regions. We apply DCF on maps investigate its reliability in high-density molecular clumps dense cores where self-gravity significant. validity assumptions step by compare model estimated derive correction factors...
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 report on Atacama Large Millimeter/submillimeter Array observations of polarized dust emission at 1.2 mm from NGC6334I, a source known for its significant flux outbursts. Between five months, our data show no substantial change in total intensity and modest 8% variation linear polarization, suggesting phase stability or the conclusion outburst. The magnetic field, inferred this emission, displays predominantly radial pattern northwest to southeast with intricate disturbances...
Abstract A complete understanding of the initial conditions high-mass star formation and what processes determine multiplicity requires study magnetic field in young massive cores. Using Atacama Large Millimeter/submillimeter Array (ALMA) 250 GHz polarization observations (0 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mover accent="true"> <mml:mrow> <mml:mi>.</mml:mi> </mml:mrow> <mml:mi>″</mml:mi> </mml:mover> </mml:math> 3 = 1000 au) ALMA 220...
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...
We present ALMA dust polarization and molecular line observations toward 4 clumps (I(N), I, IV, V) in the massive star-forming region NGC 6334. In conjunction with large-scale data from JCMT, Planck, NANTEN2, we make a synergistic analysis of relative orientations between magnetic fields ($\theta_{\mathrm{B}}$), column density gradients ($\theta_{\mathrm{NG}}$), local gravity ($\theta_{\mathrm{LG}}$), velocity ($\theta_{\mathrm{VG}}$) to investigate multi-scale (from $\sim$30 pc 0.003 pc)...
We present 1.3 mm ALMA dust polarization observations at a resolution of $\sim$0.02 pc three massive molecular clumps, MM1, MM4, and MM9, in the infrared dark cloud G28.34+0.06. With sensitive high-resolution continuum data, MM1 is resolved into cluster condensations. The magnetic field structure each clump revealed by polarized emission. found trend decreasing emission fraction with increasing Stokes $I$ intensities MM4. Using angular dispersion function method (a modified...
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...
Abstract We observe the magnetic field morphology toward a nearby star-forming filamentary cloud, G202.3+2.5, using James Clerk Maxwell Telescope/POL-2 850 μ m thermal dust polarization observations with an angular resolution of 14.″4 (∼0.053 pc). The average orientation is found to be perpendicular filaments, while showing different behaviors in four subregions, suggesting various effects from filaments’ collision these subregions. With kinematics obtained by <?CDATA...
Abstract We have comprehensively studied the multiscale physical properties of massive infrared dark cloud G28.34 (the Dragon cloud) with dust polarization and molecular line data from Planck, FCRAO-14 m, James Clerk Maxwell Telescope, Atacama Large Millimeter/submillimeter Array. find that averaged magnetic fields clumps tend to be either parallel or perpendicular cloud-scale fields, while cores in clump MM4 aligned fields. Implementing relative orientation analysis (for column density...