AI 中文总结
本研究利用SRG/eROSITA数据与SLOW模拟，探究A3266外围至3R₁₀₀区域，发现其与西北向星系群间的X射线纤维结构，揭示A3266沿宇宙网的持续并合过程。
AI 中文摘要
阿贝尔3266（A3266）是一个动力学活跃的星系团，嵌在红移相近的星系群与星系团构成的致密环境中。Spektrum Roentgen Gamma（SRG）/eROSITA全天巡天数据为研究星系团外围的暗弱X射线辐射提供了可能。我们探究了此前未被研究的A3266外围区域，直至$3R_{100}$，表征其最近的邻近星系群，并利用X射线辐射与星系数密度搜寻连接纤维结构。我们在选定的区域与扇区开展了X射线成像、表面亮度及光谱分析，辅以NASA/IPAC河外数据库（NED）的成员星系分布，并与宇宙学模拟Simulating the LOcal Web（SLOW）进行对比。我们探测到一条连接A3266与其最近西北向星系群的X射线纤维结构，其三维长度为$L_{R_{200}\text{--}R_{200}} = {1.1}_{-0.1}^{+0.5}\\,\mathrm{Mpc}$，显著性为$3.6\\,\sigma$。该星系群呈现冷核特性，嵌在纤维结构中。该纤维结构的温度为$T={1.2}_{-0.2}^{+0.3}\\,\mathrm{keV}$，金属丰度为$Z={0.07}_{-0.05}^{+0.09}\\,Z_{\odot}$，假设几何结构简单，其电子数密度为$n_{\rm e}={8}_{-2}^{+1}\times 10^{-5}\\,\mathrm{cm}^{-3}$。我们的发现揭示了A3266周围连贯的星系群网络，追踪其沿大尺度结构的持续并合过程。该纤维结构比原始暖热星系际介质更热、更致密，符合经星系团环境处理、受西北向星系群下落影响的气体特征。与SLOW的对比显示，观测到的星系群分布与纤维连接，与嵌在宇宙网中、正活跃吸积的星系团定性一致。
英文摘要
Abell 3266 (A3266) is a dynamically active galaxy cluster embedded in a dense environment of galaxy groups and clusters at similar redshift. Data from the Spektrum Roentgen Gamma (SRG)/eROSITA all-sky survey enable the study of faint X-ray emission in cluster outskirts. We investigate the previously unexplored outskirts of A3266 out to $3R_{100}$, characterize its nearest neighboring galaxy group, and search for connecting filaments using X-ray emission and galaxy number density. We performed X-ray imaging, surface brightness, and spectral analyses in selected regions and sectors. These were complemented by the distribution of member galaxies from the NASA/IPAC Extragalactic Database NED and by comparison with the cosmological simulation Simulating the LOcal Web (SLOW). We detect an X-ray filament connecting A3266 to its nearest northwestern group over a 3D length of $L_{R_{200}\text{--}R_{200}} = {1.1}_{-0.1}^{+0.5},\mathrm{Mpc}$ with a significance of $3.6,σ$. The group exhibits cool-core properties and is embedded within the filament. The filament has a temperature of $T={1.2}_{-0.2}^{+0.3},\mathrm{keV}$, metallicity $Z={0.07}_{-0.05}^{+0.09},Z{\odot}$, and, assuming a simple geometry, an electron number density of $n_{\rm e}={8}_{-2}^{+1}\times 10^{-5},\mathrm{cm}^{-3}$. Our findings reveal a coherent network of galaxy groups around A3266, tracing its ongoing assembly along the large-scale structure. The filament is hotter and denser than expected for pristine warm-hot intergalactic medium, consistent with gas processed in the cluster environment and influenced by the infall of the northwestern group. Comparison with SLOW shows that the observed group distribution and filamentary connections are qualitatively consistent with an actively accreting cluster embedded in the cosmic web.
Comments10 pages and 13 figures in the main text plus 2 pages and 2 figures as appendix. Astronomy & Astrophysics, accepted on June 29, 2026
DOI：10.1051/0004-6361/202660862
