Two sets of multiple-color ($B, V, R_c, I_c$) light curves of PZ UMa were observed in dependently with the 2.4 meter telescope at the Thai National Observatory and the 1 meter telescope at Yunnan Observatories. The light curves were analyzed with the Wilson-Devinney program and the two sets of light curves produced consistent results, which show that PZ UMa is a W-subtype contact binary with an extreme mass ratio ($M_{1}/M_{2} = 0.18)$. The basic physical parameters of PZ UMa were determined to be $M_{2} = 0.77(2)M_\odot$, $M_{1} = 0.14(1)M_\odot$, $R_{2} = 0.92(1)R_\odot$, $R_{1} = 0.43(1)R_\odot$, $L_{2} = 0.46(2)L_\odot$ and $L_{1} = 0.15(3)L_\odot$. The orbital period analysis of PZ UMa revealed a 13.22 year periodicity, which implies that there may be a tertiary component orbiting around the binary system. The mass and orbital radius of the tertiary component were calculated to be $M_{3} = 0.88 M_\odot$ and $a_{3} = 3.67 AU$, if the orbit was coplanar with the central binary system. It is interesting that the minimum mass of the tertiary was calculated to be $M_{3min} = 0.84 M_\odot$, which means the tertiary component is even larger than the primary star and the secondary one of PZ UMa. PZ UMa is a late-type contact binary with stellar activity. The O'Connell effect appeared on its light curves when it was observed on April 2016. However, the O'Connell effect reversed when the target was observed again on December 2016. The changes of the O'Connell effect in such a short time-scale strongly support the occurrence of rapidly changing magnetic activity on this W UMa binary.
On the origin of W UMa type Contact binaries - a new method for computation of initial masses
WUMa型二进制有两个定义特征。它们是（i）两个成分的有效温度非常相似，（ii）次级（目前质量较轻）成分相对于其当前质量而言过于明亮。我们认为后者是一个指示其质量之前的质量转移事件。对于这些恒星，我们定义了一个质量差（$δM$），这个质量差是由光度确定的质量和由拟合双星轨道确定的当前质量之间的差。我们比较了观测值的质量差与恒星模型的质量损失。我们发现观测到的W UMa型双星的初始次级质量范围为1.3-2.6 M $_{\odot}$。我们发现，A-和W-亚型接触双星有不同的范围内的初始次级质量。初始质量高于$1.8 \pm 0.1$ M $_{\odot}$的二元系统成为A-亚型，而初始质量低于此的系统成为W-亚型。只有6%的系统违反了这一行为。我们还使用以下初始质量比的倒数的约束条件获得了原色的初始质量：$0 < 1/q_i < 1$。除了两个系统外，我们发现原色的初始质量范围为0.2-1.5 M $_{\odot}$。最后，在比较我们的模型观察到的系统，我们发现的证据表明，传质过程是不保守的。我们发现，只有34%的质量从次级转移到初级。其余部分从系统中丢失。
Detailed TESS-Based Light Curve Modeling and Fundamental Parameter Estimation of 27 W UMa-Type Contact Binaries
LUX, Observatoire de Paris, CNRS, PSL（巴黎天文台，法国国家科学研究中心，巴黎文理研究大学）；Astronomy Department of the Raderon AI Lab.（拉德罗恩人工智能实验室天文学系）；Yazd Branch of the National Organization for Development of Exceptional Talents (SAMPAD)（伊朗特殊天赋人才开发组织亚兹德分校）；Yazd Desert Night Sky Astronomy Institute（亚兹德沙漠夜空天文研究所）
Photometric investigation and orbital period analyses of the W UMa binaries FP Lyn, FV CVn and V354 UMa
给出了FP Lyn、FV CVn和V354 UMa的新光变曲线和光度解。发现这三个系统都是W型浅接触双星。此外，很明显，FP Lyn和V354 UMa的光变曲线是不对称的。因此，在主星FP Lyn上增加了一个热点，而在副星V354 UMa上增加了一个暗点。与此同时，我们在FP Lyn的光度解决方案中添加了第三盏灯，以获得最终结果。对于FP Lyn，获得的质量比和填充因子为$q=1.153$和$f=13.4\%$，对于FV CVn，获得的质量比和填充因子为$q=1.075$和$f=4.6\%$，对于V354 UMa，获得的质量比和填充因子为$q=3.623$和$f=10.7\%$。对这三个系统轨道周期的研究表明，它们的轨道周期是变化的。发现FP Lyn和V 354 Uma分别存在着长期增长的组分，其增长率分别为$dp/dt=4.19\times10^{-7}$ d yr $^{-1}$和$dp/dt=7.70\times10^{-7}$ d yr $^{-1}$，这可能是由质量较小的组分向质量较大的组分的守恒质量转移引起的。此外，还发现了FV CVn的一些可变成分，即频率为$dp/dt=-1.13\times10^{-6}$ d yr $^{-1}$，伴随着振幅和周期分别为0.0069天和10.65年的周期振荡。长期下降的最可能的解释是角动量损失。而附加分量的存在是对周期性变化的最合…
BSN-VI: Multiband Light Curve Modeling of Four W UMa-Type Contact Binaries I. Revisiting Energy Transfer Mechanisms and Luminosity Behavior
BSN Project（BSN项目）；Independent researcher（独立研究者）；LUX, Observatoire de Paris, CNRS, PSL（巴黎天文台，法国国家科学研究中心，巴黎文理研究大学）；Department of Astronomy, Raderon AI Lab（天文学系，拉德伦人工智能实验室）；Instituto de Astronomía, UNAM（墨西哥国立自治大学天文学研究所）；European Southern Observatory（欧洲南方天文台）；Department of Astronomy and Space Science, Faculty of Science, Erciyes University（埃尔吉耶斯大学理学院天文学与空间科学系）；Erciyes University, Astronomy and Space Science Observatory Application and Research Center（埃尔吉耶斯大学天文与空间科学观测应用与研究中心）；Department of Physics, Faculty of Arts and Sciences, Çanakkale Onsekiz Mart University（恰纳卡莱18三月大学文理学院物理系）；Astrophysics Research Center and Observatory, Çanakkale Onsekiz Mart University（恰纳卡莱18三月大学天体物理学研究中心和天文台）；Variable Stars South (VSS), Congarinni Observatory（南变星组织（VSS），康加里尼天文台）
BSN-VII: Photometric Light Curve Study of Three Cool, Large-Amplitude, Low Mass, W-Subtype Contact Binaries
LUX, Observatoire de Paris, CNRS, PSL（巴黎天文台）；Astronomy Department, Raderon AI Lab.（拉德伦人工智能实验室天文学系）；Instituto de Astronomía, UNAM（墨西哥国立自治大学天文学研究所）；Farzanegan Institute（法尔扎内甘学院）；Farhangian Institute（法尔洪吉安学院）；Damghan Branch of the National Organization for Development of Exceptional Talents (SAMPAD)（国家特殊才能发展组织达姆甘分部）；IPSA Institut Polytechnique des Sciences Avancées（高级科学理工学院）；Çanakkale Onsekiz Mart University, Faculty of Science, Department of Physics（恰纳卡莱18三月大学理学院物理学系）；Çanakkale Onsekiz Mart University, Astrophysics Research Center and Ulupnar Observatory（恰纳卡莱18三月大学天体物理研究中心和乌鲁普纳观测站）
Mass-transfer properties of overcontact systems in the Kepler eclipsing binary catalog
我们从开普勒食双星目录中选择了质量转移双星候选者，并研究了质量转移速率对几个天体物理量的依赖性，包括轨道周期，半长轴，质量比，填充因子，温度和质量。我们选择这些候选人使用$O-C$图和计算它们的传质速率。初级质量是从质量-温度关系中获得的，组成星的温度是从克卜勒食联星的温度目录中提取的。过度接触系统的质量传递速率与天体物理量的关系似乎与半分离或分离系统的不同。这些关联表明，随着质量交换的发展，从质量较大的组分到质量较小的组分（从质量较小的组分到质量较大的组分）的质量交换通常会变得快速（缓慢）。然而，对于质量从大到小的组分的质量交换，这种趋势对于具有短周期（$P<0.4$ d）和低质量（$M_1<1.2$ M $_\odot$）的双星是不合理的，因为这些双星的相关性与具有长周期和高质量的双星相反。这些不同的相关性可能是由WUMa系统的亚型之间的相关性差异引起的（即，W型和A型）。或者，当质量比反转后，质量从大到小的组分再次发生质量交换时，其性质可能与第一次质量交换的性质不同。
Multicolor study of V1009 Per, a close binary system at the beginning of the overcontact phase, and of CRTS J031642.2+332639, a new binary system in the same field
CW Cas: A solar-type contact binary system with an unseen third companion in a hierarchical quadruple system
Yunnan Observatories, Chinese Academy of Sciences（中国科学院云南天文台）；University of Chinese Academy of Sciences（中国科学院大学）；Ulugh Beg Astronomical Institute, Uzbekistan Academy of Sciences（乌兹别克斯坦科学院乌鲁格别克天体物理研究所）
Spectroscopic and Decade-long Photometric Observations of the Contact Binary V2790 Ori: Evidence for a Brown Dwarf Companion and a Solar-like Magnetic Activity Cycle
