The last decade showed an impressive observational effort from the photometric and spectroscopic point of view for ancient stellar clusters in our Galaxy and beyond. The theoretical interpretation of these new observational results requires updated evolutionary models and isochrones spanning a wide range of chemical composition. With this aim we built the new "Pisa Stellar Evolution Database" of stellar models and isochrones by adopting a well-tested evolutionary code (FRANEC) implemented with updated physical and chemical inputs. In particular, our code adopts realistic atmosphere models and an updated equation of state, nuclear reaction rates and opacities calculated with recent solar elements mixture. A total of 32646 models have been computed in the range of initial masses 0.30 - 1.10 Msun for a grid of 216 chemical compositions with the fractional metal abundance in mass, Z, ranging from 0.0001 to 0.01, and the original helium content, Y, from 0.25 to 0.42. Models were computed for both solar-scaled and alpha-enhanced abundances with different external convection efficiencies. Correspondingly, 9720 isochrones were computed in the age range 8 - 15 Gyr, in time steps of 0.5 Gyr. The whole database is available to the scientific community on the web. Models and isochrones were compared with recent calculations available in the literature and with the color-magnitude diagram of selected Galactic globular clusters. The dependence of relevant evolutionary quantities on the chemical composition and convection efficiency were analyzed in a quantitative statistical way and analytical formulations were made available for reader's convenience.
Two stellar clocks, one history: a Gaia colour-magnitude-diagram reconstruction of the solar-neighbourhood star-formation history tested against white dwarfs
Università di Pisa（比萨大学）；INFN（意大利国家核物理研究所）；INAF - Osservatorio di Astrofisica e Scienza dello Spazio di Bologna（博洛尼亚天体物理学与空间科学天文台）
The Hypatia Catalog Database: A Web-Based Interface for Exploring Stellar Abundances
Hypatia星表数据库（www.hypatiacatalog.com）是最大的太阳附近恒星高分辨率恒星丰度数据库。它目前在5，986颗恒星中提供了72种元素和物种，其中347颗恒星拥有行星。Hypatia目录数据库具有交互式表格和多个绘图界面，可以轻松访问和探索Hypatia目录中的恒星丰度数据和属性（Hinkel et al. 2014，2016，2017）。Hypatia星表是一个多维的、融合的数据集，包括从仔细挑选的文献来源中对距离太阳150 pc以内的FGKM型恒星的恒星丰度测量，目前共有161个数据集，测量了[Fe/H]和至少一个其他元素。除了丰度外，在适用的情况下，在线Hypatia目录数据库还提供了恒星属性和行星属性。数据和图表也可以通过网站下载，分别用于个人代码或演示文稿。Hypatia目录和Hypatia目录数据库将继续定期更新，以纳入文献中发布的最新恒星丰度数据。
Measurements of the magnetic field strengths at the bases of stellar coronae using the magnetic-field-induced transition theory
测量恒星日冕中的磁场是极其困难的。最近，有人提出利用Fe X 257超导线的磁场感生跃迁（MIT）来测量太阳日冕磁场。我们进行了一系列的全球恒星磁流体动力学模型的正演模拟，探讨这种方法扩展到其他晚型恒星的可能性。我们首先合成了每个恒星模型的几条Fe X线的发射，然后根据MIT理论，利用Fe X 257的强度与其他几条Fe X线的强度比计算了磁场强度。最后，我们将导出的场强与模型中的场强进行了比较，并得出结论，该方法至少可以用于测量表面平均磁通量密度比太阳高一个数量级的恒星冕底的磁场强度。我们的研究表明，需要一个极紫外光谱仪进行日常测量的恒星日冕磁场。
Age Gradients in the Stellar Populations of Massive Star Forming Regions Based on a New Stellar Chronometer
理解大质量恒星形成区（MSFR）恒星形成的一个主要障碍是缺乏可靠的恒星计时器来解开它们复杂的恒星形成历史。我们提出了一个新的估计恒星年龄的新方法，采用近红外（NIR）和X射线光度学，XNUJX。恒星的质量是从金牛座云的X射线光度中使用Lx -质量关系推导出来的。J-波段光度进行比较，以质量依赖的主序前的演化模型来估计年龄。BJX对广泛的演化阶段都很敏感，从嵌入云中的盘状恒星到广泛分散的较老的前主序星。MYStIX（Massive Young Star-Forming Complex Study in Infrared and X-ray）计划使用X-射线、中红外和NIR星表描述了20个OB-dominated MSFR。MYSTIX可能的复杂成员31，784人中，有5525人使用了MYSTIX方法。我们提供了一个均匀的一组中位数年龄超过100个子集群在15 MSFR，中位数子集群年龄范围在0.5百万年和5百万年之间。重要的科学成果是发现了MYStIX地区的年龄梯度。MSFR的年龄分布呈空间分异结构，年龄分布较宽。在分子云中的模糊位置，年龄最小，在显示的星团中居中，在分布的种群中最老。近红外颜色指数J-H，一个替代措施的灭绝，可以作为一个近似的年龄预测年轻的嵌入集群。
The Stellar Abundances and Galactic Evolution Survey (SAGES). II. Machine Learning-Based Stellar parameters for 21 million stars from the First Data Release
