A5091418967- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Pulsars and Gravitational Waves Research
- Dark Matter and Cosmic Phenomena
- Radio Astronomy Observations and Technology
- Neutrino Physics Research
- Solar and Space Plasma Dynamics
- Astrophysical Phenomena and Observations
- Particle Detector Development and Performance
- Geophysics and Gravity Measurements
- Particle physics theoretical and experimental studies
- Astrophysics and Star Formation Studies
- Ionosphere and magnetosphere dynamics
- Cosmology and Gravitation Theories
- Radiation Detection and Scintillator Technologies
- Radiomics and Machine Learning in Medical Imaging
- Radiation Therapy and Dosimetry
- Galaxies: Formation, Evolution, Phenomena
- Particle Accelerators and Free-Electron Lasers
- Calibration and Measurement Techniques
- Scientific Research and Discoveries
Zhejiang Lab
2025
Yunnan University
2015-2024
Campbell Collaboration
2023
Chinese Academy of Sciences
2012-2020
Institute of High Energy Physics
2020
Abstract We present the first catalog of very-high-energy and ultra-high-energy gamma-ray sources detected by Large High Altitude Air Shower Observatory. The was compiled using 508 days data collected Water Cherenkov Detector Array from 2021 March to 2022 September 933 recorded Kilometer Squared 2020 January September. This represents main result most sensitive large coverage survey sky above 1 TeV, covering decl. −20° 80°. In total, contains 90 with an extended size smaller than 2° a...
The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of distribution, propagation, interaction in Milky Way. In this Letter, we report measurements γ from plane 10 TeV 1 PeV energies, with square kilometer array Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions inner (15°<l<125°, |b|<5°) outer (125°<l<235°, are detected 29.1σ 12.7σ significance,...
We present the first catalog of very-high energy and ultra-high gamma-ray sources detected by Large High Altitude Air Shower Observatory (LHAASO). The was compiled using 508 days data collected Water Cherenkov Detector Array (WCDA) from March 2021 to September 2022 933 recorded Kilometer Squared (KM2A) January 2020 2022. This represents main result most sensitive large coverage survey sky above 1 TeV, covering declination $-$20$^{\circ}$ 80$^{\circ}$. In total, contains 90 with an extended...
We study the nonthermal emission of pulsar wind nebulae (PWNe) from radio to TeV γ-ray energies with a simplified time-dependent injection model. In this model, relativistic particles driven by central spin-down power L(t) is blown into ambient medium and shock wave formed, which accelerates very high through Fermi acceleration mechanism in PWN. The PWN therefore consist two components, one coming directly magnetosphere other model spectra follow broken law different indices break energy Eb....
Aims. The nonthermal radiative properties of 18 pulsar wind nebulae (PWNe) are studied in the 1D leptonic model. Methods. dynamical and evolution a PWN nonradiative supernova remnant self-consistently investigated this leptons (electrons/positrons) injected with broken power-law form, emission from is mainly produced by time-dependent relativistic through synchrotron radiation inverse Compton process. Results. Observed spectral energy distributions (SEDs) all PWNe reproduced well, where...
Abstract A sub-array of the Large High Altitude Air Shower Observatory (LHAASO), KM2A is mainly designed to observe a large fraction northern sky hunt for γ-ray sources at energies above 10 TeV. Even though detector construction still underway, half array has been operating stably since end 2019. In this paper, we present data analysis pipeline and first observation Crab Nebula, standard candle in very high energy astronomy. We detect signals from Nebula both ranges 100 TeV with...
1LHAASO J0249+6022 is an extended very-high-energy gamma-ray source discovered by the Large High-Altitude Air Shower Observatory. Based on nearly 16.1 years of data from Fermi Area Telescope, we report probable emission in 0.03-1 TeV energy range. The results show that its spectrum can be well fitted a single power law with index 1.54 $\pm$ 0.17, and integral photon flux (4.28 1.03) $\times$ 10$^{-11}$ photons cm$^{-2}$ s$^{-1}$. We also considered theoretically whether non-thermal could...
The core-collapse supernova remnant (SNR) Cassiopeia A (Cas A) is one of the brightest galactic radio sources with an angular radius $\sim$ 2.5 $\arcmin$. Although no extension this source has been detected in $\gamma$-ray band, using more than 1000 days LHAASO data above $\sim 0.8$ TeV, we find that its spectrum significantly softer those obtained Imaging Air Cherenkov Telescopes (IACTs) and flux near 1$ TeV about two times higher. In combination analyses 16 years \textit{Fermi}-LAT...
Abstract 1LHAASO J0249+6022 is an extended very-high-energy γ -ray source discovered by the Large High-Altitude Air Shower Observatory. Based on nearly 16.1 yr of data from Fermi Area Telescope, we report probable emission in 0.03–1 TeV energy range. The results show that its spectrum can be well fitted a single power law with index 1.54 ± 0.17, and integral photon flux (4.28 1.03) × 10 −11 photons cm −2 s −1 . We also considered theoretically whether nonthermal could originate pulsar wind...
Abstract The pulsar wind nebula CTB 87 (G74.9+1.2) is one of the sources emitting γ -rays with energies higher than 10 TeV, as measured by Very Energetic Radiation Imaging Telescope Array System telescope. In this study, we undertake a reanalysis GeV emission from region, utilizing ∼16 yr high-energy -ray data collected Fermi Large Area Telescope. energy range 0.03–1 spectrum can be adequately described power-law model an index 1.34 ± 0.18, and integral flux calculated to (7.25 1.36) × −13...
Abstract Galaxy clusters act as reservoirs of high-energy cosmic rays (CRs). As CRs propagate through the intracluster medium, they generate diffuse γ -rays detectable by arrays such LHAASO. These result from proton–proton (pp) collisions very or inverse Compton (IC) scattering positron-electron pairs created pγ interactions ultra-high-energy (UHECRs). We analyzed -ray emission Coma, Perseus, and Virgo using LHAASO data. Diffuse was modeled a disk radius R 500 for each cluster while...
Abstract The core-collapse supernova remnant (SNR) Cassiopeia A (Cas A) is one of the brightest galactic radio sources with an angular radius <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo>∼</mml:mo> <mml:mn>2</mml:mn> <mml:mover accent="true"> <mml:mrow> <mml:mi>.</mml:mi> </mml:mrow> <mml:mi>′</mml:mi> </mml:mover> <mml:mn>5</mml:mn> </mml:math> . Although no extension this source has been detected in γ -ray band, using more than 1000 days LHAASO data...
A recent research shows that particles with a spectrum of relativistic Maxwellian plus high-energy tail can be accelerated by collisionless shocks. We investigate the possibility this new injected in pulsar wind nebulae (PWNe) from terminate shock based on study multiwavelength emission PWNe.} {The dynamics supernova remnant (SNR) and multiband nonthermal PWN inside are investigated using dynamical model electrons/positrons spectrum. In model, radiative evolution nebula non-radiative...
For decades, supernova remnants (SNRs) have been considered the prime sources of Galactic Cosmic rays (CRs). But whether SNRs can accelerate CR protons to PeV energies and thus dominate flux up knee is currently under intensive theoretical phenomenological debate. The direct test ability operate as PeVatrons be provided by ultrahigh-energy (UHE; $E_\gamma \geq 100$~TeV) $\gamma$-rays. In this context, historical SNR Cassiopeia A (Cas A) one most promising target for UHE observations. This...
ABSTRACT We report a detection of GeV γ-ray emission potentially originating from the pulsar wind nebula in CTA 1 by analysing about 15 yr Fermi Large Area Telescope data. By selecting an energy range 50 to TeV remove contamination PSR J0007+7303, we have discovered extended source with test statistic value ∼44.94 region 1. The obtained flux is measured be 6.71 ± 2.60 × 10−12 erg cm−2 s−1 spectral index 1.61 0.36, which allows for smooth connection band. also considered associated 1LHAASO...
Abstract In this study, we report the likely GeV γ -ray emissions originating from pulsar PSR J1849-0001's wind nebula (PWN) G32.64+0.53. Our analysis covers approximately 14.7 yr of data Fermi Large Area Telescope Pass 8. The position source and its spectrum matches those in X-ray TeV energy bands, so propose that is indicative PWN We interpret broadband spectral distribution (SED) using a time-dependent one-zone model, which assumes multiband nonthermal emission target can be generated by...
Abstract We analyze the quasiperiodic oscillation (QPO) of historical light curve flat-spectrum radio quasars PKS 0405-385 detected by Fermi Large Area Telescope from 2008 August to 2021 November. To identify and determine QPO signal in γ -ray curve, we use four time series analysis techniques based on frequency domains, i.e., Lomb–Scargle periodogram (LSP), weighted wavelet z -transform (WWZ), REDFIT, epoch folding. The results show that has a behavior ∼2.8 yr with significance ∼4.3 σ...
Abstract In this work, we report periodicity search analyses in the gamma-ray light curve of blazar S4 0954+658 monitoring undertaken by Fermi Large Area Telescope. Four analytical methods and a tool are adopted to detect any periodic flux modulation corresponding significance level, revealing: (i) quasi-periodic oscillation (QPO) 66 days with level >5 σ spanning over 600 from 2015 2016 (MJD 57,145–57,745), resulting continuous observation nine cycles, which is one longest cycles...
The morphology of the middle-aged supernova remnant, Cygnus Loop, seen in X-rays, is peculiar, with a blowout south region and other irregular features, such as bump west, limb planar east asymmetry between west shock profiles blowout. detailed process formation peculiar profile still unclear. We perform three-dimensional hydrodynamical simulations for remnant to revisit its evolution. In simulations, progenitor ejects an anisotropic, latitude-dependent wind, travels direction that not...
Using two-dimensional magnetohydrodynamics (MHD) simulations, we investigate the dynamical properties of Type Ia supernova remnants (SNRs) evolved either in a uniform ambient medium or from an interaction with dense clump. The initial conditions assume that expansion ejecta is free inertia power-law density distribution outer part ejecta. To include effects diffusive shock acceleration process and escape accelerated particles front, use different adiabatic indices simulations to study...
eHWC J2019+368 is one of the sources emitting $\gamma$-rays with energies higher than 100 TeV based on recent measurement High Altitude Water Cherenkov Observatory (HAWC), and origin still in debate. The pulsar PSR J2021$+$3651 spatially coincident source. We investigate theoretically whether multiband nonthermal emission can originate from wind nebula (PWN) G75.2$+$0.1 powered by J2021$+$3651. In model, spin-down power transferred to high-energy particles magnetic field nebula. As an energy...