Y. L. Feng
A5101729414- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Radio Astronomy Observations and Technology
- Black Holes and Theoretical Physics
- Radiation Therapy and Dosimetry
- Noncommutative and Quantum Gravity Theories
- Advanced Optical Sensing Technologies
- Pulsars and Gravitational Waves Research
- Surface Roughness and Optical Measurements
- Astro and Planetary Science
- Cosmology and Gravitation Theories
- Optical Systems and Laser Technology
- Advanced X-ray and CT Imaging
- Particle Detector Development and Performance
Tibet University
2019-2025
Shandong University
2023-2024
Zhejiang Lab
2024
Purple Mountain Observatory
2022
Chinese Academy of Sciences
2019
Institute for Nuclear Research
2019
Institute of High Energy Physics
2019
University of Chinese Academy of Sciences
2019
Sichuan University
2019
Hebei Normal University
2019
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 measurements of all-particle energy spectrum and mean logarithmic mass cosmic rays in range 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 December 2022, which is based on a nearly composition-independent reconstruction method, achieving unprecedented accuracy. Our analysis reveals position knee at 3.67±0.05±0.15 PeV. Below knee, spectral index found to be -2.7413±0.0004±0.0050, while above it -3.128±0.005±0.027, with sharpness transition measured...
Recently, the LHAASO Collaboration published detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with highest energy photon reaching 1.4 PeV. The first PeV γ rays from astrophysical may provide a very sensitive probe effect Lorentz invariance violation (LIV), which results in decay high-energy superluminal scenario and hence sharp cutoff spectrum. Two are studied this work. No signature existence LIV is found their spectra, lower limits on scale derived. Our show that first-order...
Abstract The first source catalog of the Large High Altitude Air Shower Observatory (LHAASO) reported detection a very high energy gamma-ray source, 1LHAASO J1219+2915. This Letter presents further detailed study spectral and temporal behavior this pointlike source. best-fit position TeV (R.A. = 185.°05 ± 0.°04, decl. 29.°25 0.°03) is compatible with NGC 4278 within ∼0.°03. Variation analysis shows an indication variability on timescale few months in band, which consistent low-frequency...
The diffuse Galactic gamma-ray emission is a very important tool used to study the propagation and interaction of cosmic rays in Milky Way. In this Letter, we report measurements from plane---covering longitudes 15\ifmmode^\circ\else\textdegree\fi{} 235\ifmmode^\circ\else\textdegree\fi{} latitudes $\ensuremath{-}5\ifmmode^\circ\else\textdegree\fi{}$ $+5\ifmmode^\circ\else\textdegree\fi{}$, an energy range 1 25 TeV---made with Water Cherenkov Detector Array (WCDA) Large High Altitude Air...
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 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...
On 9 October 2022, the Large High Altitude Air Shower Observatory (LHAASO) reported observation of very early TeV afterglow brightest-of-all-time gamma-ray burst 221009A, recording highest photon statistics in band ever obtained from a burst. We use this unique to place stringent constraints on energy dependence speed light vacuum, manifestation Lorentz invariance violation (LIV) predicted by some quantum gravity (QG) theories. Our results show that 95% confidence level lower limits QG...
Abstract The observation of short gamma ray bursts (SGRBs) in the TeV energy range plays an important role understanding radiation mechanism and probing potential new physics, such as Lorentz invariance violation (LIV). However, no SGRBs have been observed this owing to duration weakness current experiments. New experiments with technology are required detect very high (VHE) emission SGRBs. In study, we simulate VHE γ -ray emissions from calculate annual detection rate High Altitude...
The High Altitude Detection of Astronomical Radiation (HADAR) experiment is a refracting terrestrial telescope array based on the atmospheric Cherenkov imaging technique. It hybrid consisting four water-lens telescopes and surrounding scintillation detector for observing light induced by 10 GeV–10 TeV cosmic rays gamma in atmosphere. mainly consists hemispherical lens with diameter 5 m acting as collector, cylindrical metal tank 4 radius 7 height, an system at bottom tank. sky region covered...
The detection of GW170817/GRB170817A implied the strong association between short gamma-ray bursts (SGRBs) and binary neutron star (BNS) mergers which produce gravitational waves (GWs). More evidence is needed to confirm reveal physical processes BNS mergers. upcoming High Altitude Detection Astronomical Radiation (HADAR) experiment, excelling in a wide field view (FOV) large effective area above tens GeV, hope for prompt very-high-energy (VHE; > 10 GeV) SGRBs. aim this paper simulate...
Abstract The High Altitude Detection of Astronomical Radiation (HADAR) is a novel wide-field Cherenkov Telescope. It designed for gamma-ray astronomy in the energy range 10 GeV to 100 TeV, with bursts (GRBs) being one its primary research focuses. To assess complementary capabilities, this study first presents Crab sensitivity HADAR. Then, compare GRBs, observation time all experiments standardized s. clearly demonstrate HADAR’s advantages, we estimate observational results 221009A-like GRB....
The attenuation length of the muon content in extensive air showers provides important information regarding generation and development showers. This can be used not only to improve description such but also test fundamental models hadronic interactions. Using data from LHAASO-KM2A experiment, high-energy was studied. measured experimental energy range 0.3 30 PeV using constant intensity cut method. By comparing with predictions interaction (-II-04, 2.3d, -), it is evident that LHAASO...
In gamma ray astronomy, the energy range from sub-100GeV to TeV is crucial due where there a gap between space experiments and ground-based ones. addition, observations in this are expected provide more details about high emission GRBs,and thus understand EBL. Based on observation results related knowledge, scientists may be able unveil mysteries of galaxy formation evolution early universe. One principal issues for next generation Imaging Atmospheric Cherenkov Telescopes (IACT) achieve...
EN-detectors (Electron-Neutron Detector) can provide detection of both electrons and thermal neutrons generated in ground by secondary hadrons extensive air shower (EAS). The 400 EN-detector array, so called ENDA Detector Array), was proposed to add into the LHAASO (Large High Altitude Air Shower Observatory) project improve its capability EAS hybrid detection. will be located at center first 1/4 KM2A surface scintillator array. Supported Tibet University, Institute Energy Physics Chinese...
The observation of short gamma ray bursts (SGRBs) in the TeV energy range plays an important role understanding radiation mechanism and probing new areas physics such as Lorentz invariance violation. However, no SGRB has been observed this due to duration SGRBs weakness current experiments. New experiments with technology are required detect sub-TeV SGRBs. In work, we observe very high (VHE) $γ$-ray emissions from calculate annual detection rate High Altitude Detection Astronomical Radiation...