Diffuse γ-ray emission toward the massive star-forming region, W40 Xiao-Na Sun, Rui-Zhi Yang, Yun-Feng Liang, Fang-Kun Peng, Hai-Ming Zhang, Xiang-Yu Wang and Felix Aharonian A&A, 639 (2020) A80 Published online: 13 July 2020 DOI: 10.1051/0004-6361/202037580