A5066945189- Gamma-ray bursts and supernovae
- SAS software applications and methods
- Astrophysical Phenomena and Observations
- Astronomical Observations and Instrumentation
- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Pulsars and Gravitational Waves Research
- Astrophysics and Cosmic Phenomena
- Astro and Planetary Science
- Galaxies: Formation, Evolution, Phenomena
- Solar and Space Plasma Dynamics
- Nuclear Physics and Applications
- Thyroid Cancer Diagnosis and Treatment
- Spacecraft and Cryogenic Technologies
- Neutrino Physics Research
- Particle Detector Development and Performance
- Spectroscopy and Chemometric Analyses
- Methane Hydrates and Related Phenomena
- Statistical and numerical algorithms
- Domain Adaptation and Few-Shot Learning
- Radiation Therapy and Dosimetry
- Underwater Acoustics Research
- Connective Tissue Growth Factor Research
- Mitochondrial Function and Pathology
- Adaptive optics and wavefront sensing
Chinese Academy of Sciences
2015-2024
National Astronomical Observatories
2015-2024
Zhejiang Cancer Hospital
2021-2024
University of Hong Kong
2024
National Institute for Astrophysics
2024
University of Chinese Academy of Sciences
2016-2023
Australian Astronomical Observatory
2023
Macquarie University
2023
Cancer Hospital of Chinese Academy of Medical Sciences
2020-2022
Shaoxing People's Hospital
2022
We present the results of a Palomar Transient Factory (PTF) archival search for blue transients which lie in magnitude range between "normal" core-collapse and superluminous supernovae (i.e. with $-21\,{\leq}M_{R\,(peak)}\,{\leq}-19$). Of six events found after excluding all interacting Type~IIn Ia-CSM supernovae, three (PTF09ge, 09axc 09djl) are coincident centers their hosts, one (10iam) is offset from center, two (10nuj 11glr) precise can not be determined. All central have similar rise...
We report the discovery by Swift hard X-ray monitor of transient source J2058.4+0516 (Sw J2058+05). Our multi-wavelength follow-up campaign uncovered a long-lived (duration ≳ months), luminous (LX, iso ≈ 3 × 1047 erg s−1) and radio (νLν, 1042 counterpart. The associated optical emission, however, from which we measure redshift 1.1853, is relatively faint, this not due to large amount dust extinction in host galaxy. Based on numerous similarities with recently discovered GRB 110328A/Swift...
Variable X-ray and gamma-ray emission is characteristic of the most extreme physical processes in Universe, studying sources these energetic photons has been a major driver astronomy for past 50 years. Here we present multiwavelength observations unique selected transient, discovered by Swift, which was accompanied bright across electromagnetic spectrum, whose properties are unlike any previously observed source. We pinpoint event to center small, star-forming galaxy at redshift z=0.3534....
We have gathered optical photometry data from the literature on a large sample of Swift-era gamma-ray burst (GRB) afterglows including GRBs up to September 2009, for total 76 GRBs, and present an additional three pre-Swift not included in earlier sample. Furthermore, we publish 840 new points 42 GRB afterglows, sets 050319, 050408, 050802, 050820A, 050922C, 060418, 080413A 080810. analyzed light curves all derived spectral energy distributions with best quality, allowing us estimate host...
Stellar Explosions Stars that are born with masses greater than eight times of the Sun end their lives in luminous explosions known as supernovae. Over past decade, access to improved sky surveys has revealed rare types supernovae much more any those were before. Gal-Yam (p. 927 ) reviews these superluminous events and groups them into three classes share common observational physical characteristics. Gamma-ray bursts another type extreme explosive related death massive stars, which occur...
(Abridged). We present a sample of 77 optical afterglows (OAs) Swift detected GRBs for which spectroscopic follow-up observations have been secured. provide linelists and equivalent widths all lines redward Ly-alpha. discuss to what extent the current bursts with OA spectroscopy is biased subsample GRBs. For that purpose we define an X-ray selected optimal conditions ground-based follow up from period March 2005 September 2008; 146 fulfill our criteria. derive redshift distribution this...
From the first two seasons of Palomar Transient Factory, we identify three peculiar transients (PTF 09dav, PTF 10iuv, and 11bij) with five distinguishing characteristics: peak luminosity in gap between novae supernovae (MR ≈ −15.5 to −16.5 mag), rapid photometric evolution (trise 12–15 days), large photospheric velocities (≈6000–11,000 km s−1), early spectroscopic into nebular phase (≈1–3 months), spectra dominated by calcium. We also culled extensive decade-long Lick Observatory Supernova...
An Eγ, jet ∝ E relationship with a small scatter for current gamma-ray burst (GRB) data was recently reported, where is the beaming-corrected energy and νFν peak in local observer frame. By considering this sample of 12 GRBs known redshift, energy, break time afterglow light curves, we constrain mass density universe nature dark energy. We find that ΩM = 0.35 (at 1 σ confidence level) flat cosmological constant, w parameter an assumed static equation state -0.84 (1 σ). Our results are...
On May 31, 2011 UT a supernova (SN) exploded in the nearby galaxy M51 (the Whirlpool Galaxy). We discovered this event using small telescopes equipped with CCD cameras, as well by Palomar Transient Factory (PTF) survey, and rapidly confirmed it to be Type II supernova. Our early light curve spectroscopy indicates that PTF11eon resulted from explosion of relatively compact progenitor star evidenced rapid shock-breakout cooling seen curve, low temperature early-time spectra prompt appearance...
We present data and initial results from VLT/X-Shooter emission-line spectroscopy of 96 galaxies selected by long γ-ray bursts (GRBs) at 0.1 <z< 3.6, the largest sample GRB host spectra available to date. Most our GRBs were detected Swift 76% are 0.5 2.5 with a median zmed ~ 1.6. Based on Balmer and/or forbidden lines oxygen, nitrogen, neon, we measure systemic redshifts, star formation rates (SFR), visual attenuations (AV), oxygen abundances (12 + log (O/H)), widths (σ). study hosts up z...
The supernova (SN) PTF11iqb was initially classified as a Type IIn event caught very early after explosion. It showed narrow Wolf–Rayet (WR) spectral features on day 2 (as in SN 1998S and 2013cu), but the emission weakened quickly spectrum morphed to resemble Types II-L II-P. At late times, Hα exhibited complex, multipeaked profile reminiscent of 1998S. In terms spectroscopic evolution, we find that near twin 1998S, although with somewhat weaker interaction circumstellar material (CSM) at...
Owing to their utility for measurements of cosmic acceleration, Type Ia supernovae (SNe) are perhaps the best-studied class SNe, yet progenitor systems these explosions largely remain a mystery. A rare subclass SNe show evidence strong interaction with circumstellar medium (CSM), and in particular, hydrogen-rich CSM; we refer them as Ia-CSM. In first systematic search such systems, have identified 16 Ia-CSM, here present new spectra 13 them. Six Ia-CSM been well-studied previously, three...
Abstract We report our identification of the optical afterglow and host galaxy short-duration gamma-ray burst sGRB 160821B. The spectroscopic redshift is z = 0.162, making it one lowest bursts (sGRBs) identified by Swift . Our intensive follow-up campaign using a range ground-based facilities as well Hubble Space Telescope , XMM-Newton shows evidence for late-time excess near-infrared emission in addition to complex afterglow. light curve at X-ray frequencies reveals narrow jet, <?CDATA...
The nearby Type Ia supernova (SN Ia) SN 2011fe in M101 (cz = 241 km s−1) provides a unique opportunity to study the early evolution of "normal" Ia, its compositional structure, and elusive progenitor system. We present 18 high signal-to-noise spectra during first month beginning 1.2 days post-explosion with an average cadence 1.8 days. This gives clear picture how various line-forming species are distributed within outer layers ejecta, including that unburned material (C+O). follow C ii...
We present spectroscopic observations of the host galaxies 82 low-redshift Type Ia supernovae (SNe Ia) discovered by Palomar Transient Factory. determine star formation rates, gas-phase/stellar metallicities, and stellar masses ages these objects. As expected, strong correlations between SN light-curve width (stretch) age/mass/metallicity are found: fainter, faster declining events tend to be hosted older/massive/metal-rich galaxies. There is some evidence that redder SNe explode in higher...
Abstract We present James Webb Space Telescope (JWST) and Hubble (HST) observations of the afterglow GRB 221009A, brightest gamma-ray burst (GRB) ever observed. This includes first mid-IR spectra any GRB, obtained with JWST/Near Infrared Spectrograph (0.6–5.5 micron) Mid-Infrared Instrument (5–12 micron), 12 days after burst. Assuming that intrinsic spectral slope is a single power law, F ν ∝ − β , we obtain ≈ 0.35, modified by substantial dust extinction A V = 4.9. suggests above notional...
Abstract The milestone discovery of GW170817-GRB 170817A-AT 2017gfo has shown that gravitational waves (GWs) could be produced during the merger a neutron star–neutron star/black hole and in electromagnetic (EM) waves, gamma-ray burst (GRB) kilonova (KN) are generated sequence after merger. Observationally, however, EM properties before phase still unclear. Here we report peculiar precursor KN-associated long-duration GRB 211211A, providing evidence This lasts ∼0.2 s, waiting time between...
Abstract The flat segment, lasting ∼104 s, in the X-ray afterglow of GRB 051221A represents first clear case strong energy injection external shock a short gamma-ray burst (GRB) afterglow. In this work, we show that millisecond pulsar with dipole magnetic field ∼1014 Gauss could well account for injection. good quality segment thus suggests central engine may be magnetar.
We have studied the afterglow of gamma-ray burst (GRB) February 18, 2006. This is a nearby long GRB, with very low peak energy, and therefore classified as an X-ray Flash (XRF). XRF 060218 clearly associated supernova -- dubbed SN 2006aj. present early spectra for 2006aj well optical lightcurves reaching out to 50 days past explosion. Our define rise times, lightcurve shapes absolute magnitudes in U, V R bands, we compare these data other relevant supernovae. evolved quite fast, somewhat...
We show that the peculiar early optical and in particular X-ray afterglow emission of short duration burst GRB 130603B can be explained by continuous energy injection into blastwave from a supra-massive magnetar central engine. The observed energetics temporal/spectral properties late infrared bump (i.e., "kilonova") are also found consistent with ejecta launched during an NS-NS merger powered isotropic-equivalent kinetic energies both kilonova about $E_{\rm k}\sim 10^{51}$ erg, being...