标题： X射线$-$紫外光度关系 eROSITA类星体 显示英文标题

标题： The X-ray$-$UV Luminosity Relation of eROSITA Quasars

摘要： 类星体中紫外线和X射线光度之间的非线性关系已经研究了几十年。然而，由于缺乏能够解释它的综合模型，其研究仍然依赖于观测努力。这项工作专注于由eROSITA检测到的光学选择的类星体。我们介绍了在eROSITA早期数据发布（eFEDS）中收集的源以及来自eROSITA全天调查前六个月的结果（eRASS1）。我们关注在光学/紫外线波段足够明亮的类星体子集，以避免对X射线比平均光谱能量分布更亮的“爱丁顿偏差”。最终样本分别包括eFEDS和eRASS1的1,248和519个源，红移分别为$z\approx3$和$z\approx1.5$。我们发现X射线$-$紫外线光度关系在红移上没有显著演化，其斜率与以前的类星体样本汇编完全一致。该关系的固有分散约为0.2 dex，这对于可能的宇宙学应用来说足够小。然而，当前样本的有限红移范围和统计数据尚不足以获得显著的宇宙学约束。我们展示了随着eROSITA数据未来发布的变化情况。 显示英文摘要

摘要： The non-linear relation between the UV and X-ray luminosity in quasars has been studied for decades. However, as we lack a comprehensive model able to explain it, its investigation still relies on observational efforts. This work focuses on optically selected quasars detected by eROSITA. We present the properties of the sources collected in the eROSITA early data release (eFEDS) and those resulting from the first six months of eROSITA all-sky survey (eRASS1). We focus on the subset of quasars bright enough in the optical/UV band to avoid an ''Eddington bias'' towards X-ray brighter-than-average spectral energy distributions. The final samples include 1,248 and 519 sources for eFEDS and eRASS1, up to redshift $z\approx3$ and $z\approx1.5$, respectively. We found that the X-ray$-$UV luminosity relation shows no significant evolution with redshift, and its slope is in perfect agreement with previous compilations of quasar samples. The intrinsic dispersion of the relation is about 0.2 dex, which is small enough for possible cosmological applications. However, the limited redshift range and statistics of the current samples do not allow us to obtain significant cosmological constraints yet. We show how this is going to change with the future releases of the eROSITA data.