A5026512679- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astrophysical Phenomena and Observations
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Astrophysics and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Analog and Mixed-Signal Circuit Design
- Phase Equilibria and Thermodynamics
- Wood Treatment and Properties
- Natural Fiber Reinforced Composites
- Advanced Cellulose Research Studies
- Ocular Surface and Contact Lens
- Calibration and Measurement Techniques
- Adaptive optics and wavefront sensing
- Pulsars and Gravitational Waves Research
- Advanced Chemical Sensor Technologies
- Sensor Technology and Measurement Systems
- High voltage insulation and dielectric phenomena
- Photocathodes and Microchannel Plates
- Astronomical Observations and Instrumentation
- Advancements in PLL and VCO Technologies
- Quantum-Dot Cellular Automata
- Conservation Techniques and Studies
Beihang University
2024
Peking University
2017-2023
Kavli Institute for Theoretical Sciences
2017-2023
Max Planck Institute for Radio Astronomy
2020-2022
Center Point
2022
Oceaneering International (United States)
2022
Bridge University
2022
National Institute for Astrophysics
2021
Diego Portales University
2021
New Mexico Institute of Mining and Technology
2021
Until recently, determining the rotational properties of galaxies in early universe (z>4, Universe age <1.5Gyr) was impractical, with exception a few strongly lensed systems. Combining high resolution and sensitivity ALMA at (sub-) millimeter wavelengths typically strength [CII] 158um emission line from long-developed dynamical modeling tools raises possibility characterizing gas dynamics both extreme starburst normal star forming disk z~4-7. Using procedure centered around GIPSY's ROTCUR...
We report Atacama Large Millimeter/submillimeter Array (ALMA) observations of CO $(8-7)$, $(9-8)$, $\rm H_{2}O (2_{0,2}-1_{1,1})$ and OH^{+} (1_{1}-0_{1})$ NOrthern Extended Millimeter (NOEMA) $(5-4)$, $(6-5)$, $(12-11)$ $(13-12)$ towards the $z = 6.003$ quasar SDSS J231038.88+185519.7, aiming to probe physical conditions molecular gas content this source. present best sampled spectral line energy distribution (SLED) at 6.003$, analyzed it with radiative transfer code MOLPOP-CEP. Fitting...
Abstract We carry out a series of deep Karl G. Jansky Very Large Array (VLA) S -band observations sample 21 quasars at z ∼ 6. The new expand the searches radio continuum emission to optically faint quasar population highest redshift with rest-frame <?CDATA $4400\,\mathring{\rm A} $?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>4400</mml:mn> <mml:mspace width="0.25em" /> <mml:mi>Å</mml:mi> </mml:math> luminosities down $3\times {10}^{11}\ {L}_{\odot...
Abstract Observing the interstellar medium (ISM) in z ≳ 6 quasar host galaxies is essential for understanding coevolution between supermassive black holes and their hosts. To probe gas physical conditions search imprints of active galactic nuclei (AGNs) on ISM, we report ALMA observations [N ii ] 122 μ m [O i 146 lines underlying continuum from = 6.003 SDSS J231038.88+185519.7. Together with previous [C 158 iii 88 observations, use ratios these fine-structure to ISM properties. Similar other...
Abstract We present observations using the Northern Extended Millimetre Array (NOEMA) of CO and H 2 O emission lines underlying dust continuum in two quasars at z ∼ 6, i.e., P215−16 = 5.78 J1429+5447 6.18. Notably, among all published spectral line energy distributions (SLEDs) systems reveal highest lowest levels excitation, respectively. Our radiative transfer modeling SLED suggests that molecular gas heated by active galactic nuclei could be a plausible origin for high excitation. For...
JINGLE is a new JCMT legacy survey designed to systematically study the cold interstellar medium of galaxies in local Universe. As part we perform 850 µm continuum measurements with SCUBA-2 for representative sample 193 Herschel-selected M* > 109 M⊙, as well integrated CO(2–1) line fluxes RxA3m subset 90 these galaxies. The selected from fields covered by Herschel-ATLAS that are also targeted MaNGA optical integral-field spectroscopic survey. observations combined multiwavelength ancillary...
We present ALMA sub-kpc- to kpc-scale resolution observations of the [CII], CO(9-8), and OH$^{+}$\,($1_{1}$--$0_{1}$) lines along with their dust continuum emission toward FIR luminous quasar SDSS J231038.88+185519.7 at $z = 6.0031$. The [CII] brightness follows a flat distribution Sersic index 0.59. CO(9-8) line can be fit an unresolved nuclear component extended ~1. temperature drops distance from center. effective radius is smaller than that mass surface density, but consistent star...
We present new Atacama Large Millimeter/submillimeter Array (ALMA) observations of the dust continuum and [C II] 158 $\mu$m fine structure line emission towards a far-infrared-luminous quasar, ULAS J131911.29$+$095051.4 at $z=6.13$, combine Cycle 1 data with ALMA 0 data. The combined have an angular resolution $\sim$ $0.3$, resolve both on few kpc scales. is more irregular than which suggests different distributions between II]-emitting gas. confirm velocity gradient that we previously...
Abstract The Beijing–Arizona Sky Survey (BASS) is a wide and deep imaging survey that covers 5400 deg 2 area in the northern Galactic cap with 2.3 m Bok telescope using two filters ( g r bands). Mosaic z -band Legacy (MzLS) same band 4 Mayall telescope. These surveys will be used for spectroscopic targeting by Dark Energy Spectroscopic Instrument (DESI) northernmost portion of DESI footprint. This paper describes third data release (DR3) BASS, which contains photometric from all BASS MzLS...
ABSTRACT The nature of the newly discovered fast blue optical transients (FBOTs) is still puzzling astronomers. In this paper, we carry out a comprehensive analysis molecular gas, ionized and stellar populations in environment nearby FBOT AT2018cow based on ALMA, VLT/MUSE, HST/WFC3 observations. A prominent concentration 6 (± 1) × 106 M⊙ found vicinity AT2018cow, which has given rise to two active star-forming complexes with ages 4 ± 1 ≲2.5 Myr, respectively. Each complex mass 3 105 M⊙,...
Abstract We use Atacama Large Millimeter/submillimeter Array CO (2–1) observations of six low-redshift Palomar-Green quasars to study the distribution and kinematics molecular gas their host galaxies at kiloparsec-scale resolution. While content, fraction, star formation rates are similar those nearby massive, star-forming galaxies, quasar possess exceptionally compact, disky distributions with a median half-light radius 1.8 kpc mass surface densities ≳22 M ⊙ pc −2 . overall velocity field...
The Beijing-Arizona Sky Survey (BASS) is a new wide-field legacy imaging survey in the northern Galactic cap using 2.3m Bok telescope. will cover about 5400 deg$^2$ $g$ and $r$ bands, expected 5$\sigma$ depths (corrected for extinction) two bands are 24.0 23.4 mag, respectively. BASS started observations January 2015, has completed 41% of whole area as July 2016. first data release contains both calibrated images photometric catalogs obtained 2015 single-epoch 22.9 full three epochs 24.1 23.5
Abstract We present ALMA observations of the [C ii ] 158 μ m fine structure line and dust continuum emission from two quasars, SDSS J104433.04−012502.2 J012958.51−003539.7, at z = 5.78. The 0.″2 resolution map gas on kiloparsec scales. spatially resolved shows a similar trend decreasing ]–far-infrared (FIR) ratios with increasing FIR surface brightnesses as was found in infrared luminous galaxies intense star formation. confirm velocity gradients previously J0129−0035. No clear evidence...
We present Karl G. Jansky Very Large Array (VLA) S- (2--4 GHz), C- (4--8 and X-band (8--12 GHz) continuum observations toward seven radio-loud quasars at $z>5$. This sample has previously been found to exhibit spectral peaks observed-frame frequencies above $\sim$1 GHz. also upgraded Giant Metrewave Radio Telescope (uGMRT) band-2 (200 MHz), band-3 (400 band-4 (650 MHz) radio eight $z>5$, selected from our previous GMRT survey, in order their low-frequency synchrotron emission. Combined with...
We present Karl G. Jansky Very Large Array (VLA) observations of the CO (2$-$1) line emission towards three far-infrared luminous quasars at $z\sim6$: SDSS J231038.88$+$185519.7 and J012958.51$-$003539.7 with $\sim0\farcs6$ resolution J205406.42$-$000514.8 $\sim2\farcs1$ resolution. All sources are detected in -- one source is marginally resolved, other two appear as point sources. Measurements allow us to calculate molecular gas mass even without a excitation model. The inferred masses...
Abstract The formation of the first supermassive black holes is expected to have occurred in some most pronounced matter and galaxy overdensities early universe. We conducted a submillimeter wavelength continuum survey 54 z ∼ 6 quasars using Submillimeter Common-User Bolometre Array-2 on James Clerk Maxwell Telescope study environments around quasars. identified 170 galaxies (SMGs) with above 3.5 σ detections 450 or 850 μ m maps. Their far-IR luminosities are (2.2–6.4) × 10 12 L ⊙ , their...
Abstract We present NOrthern Extended Millimeter Array observations of CO(8–7), (9–8), and (10–9) lines, as well the underlying continuum for two far-infrared luminous quasars: SDSS J2054-0005 at z = 6.0389 J0129-0035 5.7788. Both quasars were previously detected in CO (2–1) (6–5) transitions, making them candidates studying spectral line energy distribution (SLED) ∼ 6. Utilizing radiative transfer code CLOUDY, we fit SLED with heating mechanisms, including photodissociation region (PDR)...
We present Giant Metrewave Radio Telescope (GMRT) 323 MHz radio continuum observations toward 13 radio-loud quasars at $z>5$, sampling the low-frequency synchrotron emission from these objects. Among 12 targets successfully observed, we detected 10 above $4σ$ significance, while 2 remain undetected. All of sources appear as point sources. Combined with previous detections literature, 9 have power-law spectral energy distributions throughout range; for some flux density drops increasing...
Transparent jute fiber (TJF) was prepared from delignified (DJF) and subjected to various surface knitting densities (190 340 g/m2) before epoxy resin (ER) impregnation under vacuum. The preparation process properties of TJF were evaluated. mechanical morphology the samples also studied. compared with transparent coir (TCF) balsa wood (TBW). Optical properties, such as color, optical transmittance, visual haze, natural (JF) measured better understand influence delignification. experimental...
The power supply rejection (PSR) based on closed-loop low-dropout regulator (LDO) is analyzed to achieve high PSR in LDO, and help the designer meet requirement when considering other performances of LDO. Using small signal model MOS transistor, Kirchhoff's current/voltage law, tool Mathematica, with DC gain, poles, zeros stage six kinds basic amplifiers LDO theoretically, proved by simulation Cadence Spectre. By tabling eight error amplifier (EA) composite structures two stages, best...
In this study, we expand the coverage and improve homogeneity of distribution MILES template stars in parameter space, as well extend wavelength spectra to far red beyond Ca ii triplet. To achieve this, have carried out a major observational campaign using two long-slit spectrographs: OMR mounted on National Astronomy Observatory China (NAOC) 2.16-m telescope Yunnan Faint Object Spectrograph Camera (YFOSC) Astronomical (YNAO) 2.4-m telescope. The original sample is based library,...
We report deep Karl G. Jansky Very Large Array (VLA) observations of the optically ultraluminous and radio-quiet quasar SDSS J010013.02 + 280225.8 (hereafter J0100+2802) at redshift $z=$6.3. detected radio continuum emission 1.5 GHz, 6 10 GHz. This leads to a power-law spectral index $\alpha = -0.52\pm0.18$ ($S \propto \nu^{\alpha}$). The source is unresolved in all VLA bands with an upper limit size $0.2^{\prime \prime}$ (i.e., $\sim$ 1.1 kpc) find variability flux density (increase by...