Large High Altitude Air Shower Observatory
The Large High Altitude Air Shower Observatory (LHAASO) is a gamma-ray and cosmic-ray observatory in Daocheng, in the Garzê Tibetan Autonomous Prefecture in Sichuan, China. It is designed to observe air showers triggered by gamma rays and cosmic rays.[1] The observatory is at an altitude of 4,410 metres (14,470 ft) above sea level.[2] Observations started in April 2019.[3]
The observatory covers an area of some 145 hectares (360 acres). It has three underground observing pools, each “more than triple the size of the Water Cube (National Aquatic Center) in Beijing”. One of the pools is designed to contain 100,000 tonnes (98,000 long tons; 110,000 short tons) of water. The pools will contain 12 telescopes to capture high-energy photons. Cherenkov radiation detectors are used. Research teams from Australia and Thailand will participate in the project directly, with others expressing interest.[4]
The observatory works essentially as the CASA-MIA observatory did but with a bigger surface array, better muon detectors, improved designed layout and at higher altitude.[5]
Scientific results
[edit]On 17 May, 2021, LHAASO Discovers a Dozen PeVatrons and Photons Exceeding 1 PeV including one at 1.4 PeV.[6][7]
On 26 February, 2024, LHAASO reported the discovery of "a giant ultra-high-energy gamma-ray bubble structure in the Cygnus star-forming region." It contains multiple photons exceeding 1 PeV and at least one reaching 2.5 PeV, leading scientists to identify the presence of a "super cosmic ray accelerator" within the structure.[8][9]
See also
[edit]References
[edit]- ^ Vernetto, S; LHAASO Collaboration (May 2016). "Gamma Ray Astronomy with LHAASO". Journal of Physics: Conference Series. 718 (5): 052043. Bibcode:2016JPhCS.718e2043V. doi:10.1088/1742-6596/718/5/052043. ISSN 1742-6588.
- ^ Zhu, H.; Zhu, F. R.; Zhou, X. X.; Zhao, Y.; Zhang, X.; Zhang, S. S.; Zhang, M. F.; Zhang, L.; Zhang, B. (2019-05-07). "The Large High Altitude Air Shower Observatory (LHAASO) Science White Paper". arXiv:1905.02773v1 [astro-ph.HE].
- ^ Cyranoski, David (2019-05-08). "China's mountain observatory begins hunt for origins of cosmic rays". Nature. doi:10.1038/d41586-019-01467-1. PMID 32376923. S2CID 165029766.
- ^ Chinese scientists' pursuit of cosmic rays opens windows on universe, [SpaceDaily.com], 2019-10-24
- ^ Xin, Ling. "Highest-Energy Particles Yet Arrive from Ancient Crab Nebula". Scientific American. Retrieved 2021-07-14.
- ^ Physics, Institute of High Energy (2021-05-18). "LHAASO Discovers a Dozen PeVatrons and Photons Exceeding 1 PeV and Launches Ultra-High-Energy Gamma Astronomy Era ----Institute of High Energy Physics". english.ihep.cas.cn (in Chinese). Archived from the original on 2022-01-20. Retrieved 2022-10-17.
- ^ Cao, Z.; Aharonian, F.A.; An, Q.; et al. (2021-05-17). "Ultrahigh-energy photons up to 1.4 petaelectronvolts from 12 γ-ray Galactic sources". Nature. 594 (7861): 33–36. Bibcode:2021Natur.594...33C. doi:10.1038/s41586-021-03498-z. PMID 34002091. S2CID 234768604.
- ^ LHAASO Collaboration (2024-02-26). "An ultrahigh-energy γ-ray bubble powered by a super PeVatron". Science Bulletin. 69 (4): 449–457. arXiv:2310.10100. doi:10.1016/j.scib.2023.12.040. ISSN 2095-9273.
- ^ Sciences, Chinese Academy of. "LHAASO discovers giant ultra-high-energy gamma-ray bubble, identifying the first super PeVatron". phys.org. Retrieved 2024-02-26.