A5000033778- Gamma-ray bursts and supernovae
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysical Phenomena and Observations
- Astrophysics and Cosmic Phenomena
- Galaxies: Formation, Evolution, Phenomena
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Climate variability and models
- Pulsars and Gravitational Waves Research
- Astro and Planetary Science
- Influenza Virus Research Studies
- Cryospheric studies and observations
- Scientific Research and Discoveries
- Radioactivity and Radon Measurements
- Meteorological Phenomena and Simulations
- Arctic and Antarctic ice dynamics
- Geophysics and Gravity Measurements
- Geophysics and Sensor Technology
- Nuclear Physics and Applications
- Quantum and Classical Electrodynamics
- Hydrology and Watershed Management Studies
- Atomic and Subatomic Physics Research
- Medical Imaging Techniques and Applications
- Magnetic confinement fusion research
California Institute of Technology
2024
Nanjing University of Information Science and Technology
2022-2024
University of Arizona
2018-2023
Shanghai Astronomical Observatory
2013-2017
University of Chinese Academy of Sciences
2015
Abstract We present volume-limited samples of cataclysmic variables (CVs) and AM CVn binaries jointly selected from SRG/eROSITA eRASS1 Gaia DR3 using an X-ray + optical color–color diagram (the “X-ray Main Sequence”). This tool identifies all CV subtypes, including magnetic low-accretion rate systems, in contrast to most previous surveys. find 23 CVs, 3 which are CVns, out 150 pc the Western Galactic Hemisphere. Our sample is spectroscopically verified complete down L X = 1.3 × 10 29 erg s...
Abstract We identify the progenitor star of SN 2023ixf in Messier 101 using Keck/NIRC2 adaptive optics imaging and pre-explosion HST/ACS images. The supernova, localized with diffraction spikes high-precision astrometry, unambiguously coincides a candidate mF814W = 24.87 ± 0.05 (AB). Given its reported infrared excess semi-regular variability, we fit time-dependent spectral energy distribution (SED) model dusty red supergiant (RSG) to combined dataset HST optical, ground-based near-infrared,...
We explore a second-order Hamiltonian vertical resonance model for X-shaped or peanut-shaped galactic bulges. The X- peanut-shape is caused by the 2:1 Lindblad with bar, two oscillation periods per orbital period in bar frame. examine N-body simulations and find that due to slowing down disc thickening during buckling, associated moves outward. consistent location of resonance, independent whether buckled not. estimate width from potential m = 4 Fourier component narrow, affecting orbits...
Abstract High-cadence, multiwavelength observations have continuously revealed the diversity of tidal disruption events (TDEs), thus greatly advancing our knowledge and understanding TDEs. In this work, we conducted an intensive optical-UV X-ray follow-up campaign TDE AT 2023lli found a remarkable month-long bump in its UV/optical light curve nearly 2 months prior to maximum brightness. The represents longest separation time from main peak among known TDEs date. outburst declines as t −4.10...
Obtaining spectroscopic observations of the progenitors core-collapse supernovae is often unfeasible, due to an inherent lack knowledge as what stars experience and when they will explode. In this Letter we present photometric progenitor activity SN 2023fyq before He-rich explodes a Type Ibn supernova. The shows exponential rise in flux prior core collapse. Complex He I emission line features are observed spectra, with P Cygni-like profile, well evolving broad base velocities order 10 000 km...
Abstract Multipeaked supernovae with precursors, dramatic light-curve rebrightenings, and spectral transformation are rare, but being discovered in increasing numbers by modern night-sky transient surveys like the Zwicky Transient Facility. Here, we present observations analysis of SN 2023aew, which showed a increase brightness following an initial luminous (−17.4 mag) long (∼100 days) unusual first peak (possibly precursor). 2023aew was classified as Type IIb supernova during changed its...
Abstract The Bright Transient Survey (BTS) aims to obtain a classification spectrum for all bright ( m peak ≤ 18.5 mag) extragalactic transients found in the Zwicky Facility (ZTF) public survey. BTS critically relies on visual inspection (“scanning”) select targets spectroscopic follow-up, which, while effective, has required significant time investment over past ∼5 yr of ZTF operations. We present BTSbot , multimodal convolutional neural network, which provides transient score individual...
We present observations of the Type IIP supernova (SN) 2024jlf, including spectroscopy beginning just 0.7 days ($\sim$17 hours) after first light. Rapid follow-up was enabled by new $\texttt{BTSbot-nearby}$ program, which involves autonomously triggering target-of-opportunity requests for transients in Zwicky Transient Facility data that are coincident with nearby ($D<60$ Mpc) galaxies and identified $\texttt{BTSbot}$ machine learning model. Early photometry non-detections shortly prior to...
Abstract We present the luminosity function and volumetric rate of a sample Type IIP supernovae (SNe) from Zwicky Transient Facility Census Local Universe survey (CLU). This is largest SNe systematic volume-limited to-date. The final includes 330 36 low-luminosity II (LLIIP) with M r ,peak > −16 mag, which triples literature LLIIP SNe. fraction <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mn>1</mml:mn> <mml:msubsup> <mml:mrow> <mml:mn>9</mml:mn>...
We present a detailed study of the Planck-selected binary galaxy cluster PLCK G165.7+67.0 (G165; $z$=0.348). A multiband photometric catalog is generated that incorporates new imaging from Large Binocular Telescope/Large Camera and Spitzer/IRAC to existing imaging. To cope with different image characteristics, robust methods are applied in extraction matched-aperture photometry. Photometric redshifts estimated for 143 galaxies 4 arcmin$^{2}$ field overlap covered by all these data. confirm...
The Legacy Survey of Space and Time (LSST) at the Vera C. Rubin Observatory will discover tens thousands extragalactic transients each night. high volume alerts demands immediate classification transient types in order to prioritize observational follow-ups before events fade away. We use host galaxy features classify transients, thereby providing upon discovery. In contrast past work that focused on distinguishing Type Ia core-collapse supernovae (SNe) using are not always accessible (e.g.,...
In late July 2018, a compound drought and heat event (CDHE) occurred in the middle of Yangtze River basin (MYRB) caused great damage to national economy. The CDHE over MYRB has been documented be linked with intraseasonal oscillations (ISOs) from different regions. However, specific roles ISOs on development cannot separated observational analysis. By using partial lateral forcing experiments driven by ISO Weather Research Forecasting (WRF) model, we found that midlatitude generated westerly...
Abstract Understanding the preferences of transient types for host galaxies with certain characteristics is key to studies physics and galaxy evolution, as well identification classification in LSST era. Here we describe a value-added database extragalactic transients—supernovae, tidal disruption events, gamma-ray bursts, other rare events—and their properties. Based on reported coordinates, redshifts, (if known) cross-identify or most likely candidates various survey catalogs, compile...
We explore the kinematics (both radial velocity and proper motion) of vertical X-shaped feature in Milky Way with an N-body bar/bulge model. From solar perspective, distance distribution particles is double-peaked fields passing through X-shape. The separation amplitude ratio between two peaks qualitatively match observed trends towards Galactic bulge. confirm clear signatures cylindrical rotation pattern mean across region. also find possible imprints coherent orbital motion inside bar...
Multi-peaked supernovae with precursors, dramatic light-curve rebrightenings, and spectral transformation are rare, but being discovered in increasing numbers by modern night-sky transient surveys like the Zwicky Transient Facility (ZTF). Here, we present observations analysis of SN 2023aew, which showed a increase brightness following an initial luminous (-17.4 mag) long (~100 days) unusual first peak (possibly precursor). 2023aew was classified as Type IIb supernova during changed its type...
ABSTRACT Transient surveys routinely detect supernovae (SNe) without obvious host galaxies. To understand the demographics of these ‘hostless’ SNe and to constrain possible properties, we identify 161 reported Name Server since 2016 that do not have hosts catalogued from pre-explosion wide-field galaxy surveys. Using forced aperture photometry, excess flux around only 56 SNe. Both thermonuclear core-collapse (CC) are present in our sample. Compared flux-limited samples with known hosts,...
Having completed its commissioning phase, the Advanced Rayleigh guided Ground-layer adaptive Optics System (ARGOS) facility is coming online for scientific observations at Large Binocular Telescope (LBT). With six laser guide stars in two constellations and corresponding wavefront sensing, ARGOS corrects ground-layer distortions both LBT 8.4m eyes with their secondary mirrors. Under regular observing conditions, this set-up delivers a point spread function (PSF) size reduction by factor of...
We identify the progenitor star of SN 2023ixf in nearby galaxy Messier 101 using Keck/NIRC2 adaptive optics imaging and pre-explosion HST/ACS images. The supernova position, localized with diffraction-spike pattern high precision relative astrometry, unambiguously coincides a single candidate m_F814W=24.96(-0.04)(+0.05). Forced photometry further recovers 2-sigma detections F673N F675W bands imposes robust flux limits on bluer bands. Given reported infrared excess semi-regular variability...
Using the LAMOST-Gaia common stars, we demonstrate that in-plane velocity field for nearby young stars are significantly different from old ones. For probably perturbed velocities similar to population mostly removed maps in $X$--$Y$ plane. The residual shows consistently move along $Y$ with faster $v_\phi$ at trailing side of local arm, while leading side, they slower azimuth direction. At both sides, averagely inward $v_R$ $-5\sim-3$ km s$^{-1}$. divergence direction implies associated a...
Abstract Cold fronts often bring catastrophic weather events, which are exacerbated under global warming. Thus, the automatic and objective identification of cold will be helpful for accurate forecasting comprehensive analysis fronts. Recently, machine learning methods have been applied to meteorological study. In this study, a front method based on deep model Mask R‐CNN is proposed automatically identify from massive data. The shows high accuracy after comparison with traditional effective...
We present the first homogeneous release of several thousand Type Ia supernovae (SNe Ia), all having spectroscopic classification, and redshifts for half sample. This release, named "DR2", contains 3628 nearby (z < 0.3) SNe discovered, followed classified by Zwicky Transient Facility survey between March 2018 December 2020. Of these, 3000 have good-to-excellent sampling 2667 pass standard cosmology light-curve quality cuts. is thus largest SN to date, increasing an order magnitude number...
Accurate classification of transients obtained from spectroscopic data are important to understand their nature and discover new classes astronomical objects. For supernovae (SNe), SNID, NGSF (a Python version SuperFit), DASH widely used in the community. Each tool provides its own metric help determine classification, such as rlap chi2/dof NGSF, Probability DASH. However, we do not know how accurate these tools are, they have been tested with a large homogeneous dataset. Thus, this work,...