发表机构
Newcastle University; Durham University; University of Southampton; Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences; The Open University; Michigan State University; University of Washington（纽卡斯尔大学; 杜伦大学; 南安普顿大学; 波兰科学院尼古拉·哥白尼天文学中心; 开放大学; 密歇根州立大学; 华盛顿大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
COBALT-BLUE模型快速精确模拟含致密天体双星的光变，整合自透镜、多普勒聚束等效应，多波段自洽计算，拟合ZTF候选源表明观测耀发多为恒星耀发，为未来巡天搜索奠定基础。
AI 中文摘要
我们提出了COBALT-BLUE，这是一个用于非吸积双星系统中发光恒星光学光变的快速公开模型，该双星系统包含一个致密天体。该模型包含了引力自透镜效应、多普勒聚束效应、椭球变化、偏心轨道几何以及随波长变化的临边昏暗效应。在足够侧向的系统里，它预测出尖锐的周期性自透镜耀发，以及耀发之外的相位锁定轨道调制。我们通过纳入基于恒星大气模拟的非线性临边昏暗定律来计算自透镜耀发轮廓，从而改进了早期模型。这使得光变曲线能够从一组物理参数出发，在多个波段上自洽地计算出来，因此为仅通过测光来约束双星参数（如致密天体质量）提供了前景，前提是观测到多个自透镜耀发。我们还提供了使用更简单临边昏暗方案的选项以节省计算开销。作为原理验证，我们将模型拟合到ZTF的14个候选自透镜源的数据上。该模型对大多数候选源的耀发形态描述良好，但我们发现最佳拟合参数在物理上不合理。我们得出结论，观测到的耀发很可能是恒星耀发而非自透镜事件。未来，我们计划利用该模型系统地搜索光学巡天数据中的双星运动特征。
英文摘要
We present COBALT-BLUE, a fast public model for the optical light curve of a luminous star in a non-accreting binary with a compact object. The model includes gravitational self-lensing, Doppler beaming, ellipsoidal variations, eccentric orbital geometry, and wavelength-dependent limb darkening. In sufficiently edge-on systems, it predicts sharp periodic self-lensing flares together with phase-locked orbital modulation outside the flare. We improve upon earlier models by including non-linear limb darkening laws based on stellar atmosphere simulations to calculate the self-lensing flare profile. This enables light curves to be self-consistently calculated in multiple wavebands from one set of physical parameters, thus offering the prospect of constraining binary parameters such as compact object mass from photometry alone if multiple self-lensing flares are observed. We also include the option to utilise simpler limb darkening prescriptions to save computational expense. As a proof of principle, we fit our model to ZTF data of 14 candidate self-lensing sources. The model describes the flare morphology well for most candidates, but we find that the best fitting parameters are not physically plausible. We conclude that the observed flares are most likely stellar flares and not self-lensing events. In future, we plan to use the model to systematically search optical survey data for signatures of binary motion.
