标题： SPT和XMM-Newton联合分析限制星系团外围非热压力 显示英文标题

标题： Constraints on Non-Thermal Pressure at galaxy cluster outskirts from a Joint SPT and XMM-Newton Analysis

摘要： 我们展示了南极望远镜（SPT）和XMM-Newton联合观测的8个质量较大的星系团（质量范围为0.8–1.7$\times$10$^{15}$M$_{\odot}$），红移范围从0.16到0.35。 采用一种新颖的SZ+X射线拟合技术，我们有效地约束了这些星系团直至引力半径处的热动力学性质。 得到的最佳拟合电子密度、去投影温度以及去投影压力剖面与之前对大质量星系团的观测结果一致。 对于样本中的大多数星系团（5/8个），熵剖面在引力半径附近表现出自相似行为。 我们进一步推导出所有星系团直至引力半径内的水动力质量、气体质量和气体分数剖面。 通过比较封闭气体分数剖面与宇宙平均气体分数剖面，我们得到了样本星系团在$>$$R_{500}$ 处的非热压力分数剖面，显示在$R_{500}$和$R_{200}$之间有一致于流体力学模拟结果的陡峭增长趋势。 我们的分析得出非热压力分数范围为 8%–28%（中位数：15 $\pm$ 11%）在$R_{500}$和 21%–35%（中位数：27 $\pm$ 12%）在$R_{200}$。 值得注意的是，在我们的样本中，只有四个星团可以获得弱引力透镜质量测量值，而在考虑了非热压力后我们恢复的总星团质量与这些测量结果一致。 显示英文摘要

摘要： We present joint South Pole Telescope (SPT) and XMM-Newton observations of 8 massive galaxy clusters (0.8--1.7$\times$10$^{15}$ M$_{\odot}$) spanning a redshift range of 0.16 to 0.35. Employing a novel SZ+X-ray fitting technique, we effectively constrain the thermodynamic properties of these clusters out to the virial radius. The resulting best-fit electron density, deprojected temperature, and deprojected pressure profiles are in good agreement with previous observations of massive clusters. For the majority of the cluster sample (5 out of 8 clusters), the entropy profiles exhibit a self-similar behavior near the virial radius. We further derive hydrostatic mass, gas mass, and gas fraction profiles for all clusters up to the virial radius. Comparing the enclosed gas fraction profiles with the universal gas fraction profile, we obtain non-thermal pressure fraction profiles for our cluster sample at $>$$R_{500}$, demonstrating a steeper increase between $R_{500}$ and $R_{200}$ that is consistent with the hydrodynamical simulations. Our analysis yields non-thermal pressure fraction ranges of 8--28% (median: 15 $\pm$ 11%) at $R_{500}$ and 21--35% (median: 27 $\pm$ 12%) at $R_{200}$. Notably, weak-lensing mass measurements are available for only four clusters in our sample, and our recovered total cluster masses, after accounting for non-thermal pressure, are consistent with these measurements.