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arXiv · 2408.09905

Observation of the $\gamma$-ray Emission from W43 with LHAASO

Zhen Cao·F. Aharonian·Y. X. Bai·Y. W. Bao·D. Bastieri·X. J. Bi·Y. J. Bi·W. Bian·J. Blunier·A. V. Bukevich·C. M. Cai·Y. Y. Cai·W. Y. Cao·Zhe Cao·J. Chang·J. F. Chang·E. S. Chen·G. H. Chen·H. K. Chen·L. F. Chen·Liang Chen·Long Chen·M. J. Chen·M. L. Chen·Q. H. Chen·S. Chen·S. H. Chen·S. Z. Chen·T. L. Chen·X. B. Chen·X. J. Chen·X. P. Chen·Y. Chen·N. Cheng·Q. Y. Cheng·Y. D. Cheng·M. Y. Cui·S. W. Cui·X. H. Cui·Y. D. Cui·B. Z. Dai·H. L. Dai·Z. G. Dai·Danzengluobu·Y. X. Diao·A. J. Dong·X. Q. Dong·K. K. Duan·J. H. Fan·Y. Z. Fan·J. Fang·J. H. Fang·K. Fang·C. F. Feng·H. Feng·L. Feng·S. H. Feng·X. T. Feng·Y. Feng·Y. L. Feng·S. Gabici·B. Gao·Q. Gao·W. Gao·W. K. Gao·M. M. Ge·T. T. Ge·L. S. Geng·G. Giacinti·G. H. Gong·Q. B. Gou·M. H. Gu·F. L. Guo·J. Guo·K. J. Guo·X. L. Guo·Y. Q. Guo·Y. Y. Guo·R. P. Han·O. A. Hannuksela·M. Hasan·H. H. He·H. N. He·J. Y. He·X. Y. He·Y. He·S. Hernández-Cadena·B. W. Hou·C. Hou·X. Hou·H. B. Hu·S. C. Hu·C. Huang·D. H. Huang·J. J. Huang·X. L. Huang·X. T. Huang·X. Y. Huang·Y. Huang·Y. Y. Huang
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Abstract

In this paper, we report the detection of the very-high-energy (VHE, $ 100{\rm\ GeV} < E < 100{\rm\ TeV} $) and ultra-high-energy (UHE, $E > 100\rm\ TeV$) $\gamma$-ray emissions from the direction of the young star-forming region W43, observed by the Large High Altitude Air Shower Observation (LHAASO). The extended $\gamma$-ray source was detected with a significance of ${\sim}16\,\sigma$ by KM2A and ${\sim}17\,\sigma$ by WCDA, respectively. The angular extension of this $\gamma$-ray source is about 0.5 degrees, corresponding to a physical size of about 50 pc. We discuss the origin of the $\gamma$-ray emission and possible cosmic ray acceleration in the W43 region using multi-wavelength data. Our findings suggest that W43 is likely another young star cluster capable of accelerating cosmic rays (CRs) to at least several hundred TeV.

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Zhen Cao, F. Aharonian, Y. X. Bai, Y. W. Bao, D. Bastieri, X. J. Bi, Y. J. Bi, W. Bian, J. Blunier, A. V. Bukevich, C. M. Cai, Y. Y. Cai, W. Y. Cao, Zhe Cao, J. Chang, J. F. Chang, E. S. Chen, G. H. Chen, H. K. Chen, L. F. Chen, Liang Chen, Long Chen, M. J. Chen, M. L. Chen, Q. H. Chen, S. Chen, S. H. Chen, S. Z. Chen, T. L. Chen, X. B. Chen, X. J. Chen, X. P. Chen, Y. Chen, N. Cheng, Q. Y. Cheng, Y. D. Cheng, M. Y. Cui, S. W. Cui, X. H. Cui, Y. D. Cui, B. Z. Dai, H. L. Dai, Z. G. Dai, Danzengluobu, Y. X. Diao, A. J. Dong, X. Q. Dong, K. K. Duan, J. H. Fan, Y. Z. Fan, J. Fang, J. H. Fang, K. Fang, C. F. Feng, H. Feng, L. Feng, S. H. Feng, X. T. Feng, Y. Feng, Y. L. Feng, S. Gabici, B. Gao, Q. Gao, W. Gao, W. K. Gao, M. M. Ge, T. T. Ge, L. S. Geng, G. Giacinti, G. H. Gong, Q. B. Gou, M. H. Gu, F. L. Guo, J. Guo, K. J. Guo, X. L. Guo, Y. Q. Guo, Y. Y. Guo, R. P. Han, O. A. Hannuksela, M. Hasan, H. H. He, H. N. He, J. Y. He, X. Y. He, Y. He, S. Hernández-Cadena, B. W. Hou, C. Hou, X. Hou, H. B. Hu, S. C. Hu, C. Huang, D. H. Huang, J. J. Huang, X. L. Huang, X. T. Huang, X. Y. Huang, Y. Huang, Y. Y. Huang. 2024-08-19. Observation of the $\gamma$-ray Emission from W43 with LHAASO. https://doi.org/10.1007/s11433-024-2477-9

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