We present a data-driven method to estimate absolute magnitudes for O- and B-type stars from the LAMOST spectra, which we combine with Gaia DR2 parallaxes to infer distance and binarity. The method applies a neural network model trained on stars with precise Gaia parallax to the spectra and predicts K _s-band absolute magnitudes with a precision of 0.25 mag, which corresponds to a precision of 12% in spectroscopic distance. For distant stars (e.g., >5 kpc), the inclusion of constraints from spectroscopic significantly improves the distance estimates compared to inferences from Gaia parallax alone. Our method accommodates for emission-line stars by first identifying them via principal component analysis reconstructions and then treating them separately for the estimation. We also take into account unresolved binary/multiple stars, which we identify through deviations in the spectroscopic from the geometric inferred from Gaia parallax. This method of binary identification is particularly efficient for unresolved binaries with near equal-mass components and thus provides a useful supplementary way to identify unresolved binary or multiple-star systems. We present a catalog of spectroscopic , extinction, distance, flags for emission lines, and binary classification for 16,002 OB stars from LAMOST DR5. As an illustration, we investigate the of the enigmatic LB-1 system, which Liu et al. had argued consists of a B star and a massive stellar-mass black hole. Our results suggest that LB-1 is a binary system that contains two luminous stars with comparable brightness, and the result is further supported by parallax from the Gaia eDR3.

我们提出了一种数据驱动的方法，可根据LAMOST光谱估算O型和B型恒星的绝对大小，并结合Gaia DR2视差来推断距离和二值性。该方法将在具有精确盖亚视差的恒星上训练的神经网络模型应用于光谱，并以0.25 mag的精度预测K _s波段绝对大小，这对应于光谱距离的精度为12％。对于遥远的恒星（例如，> 5 kpc），与仅根据盖亚视差得出的推断相比，包含光谱的约束条件显着改善了距离估计。我们的方法通过首先通过主成分分析重建来识别发射线恒星，然后针对它们分别处理来适应发射线恒星。估计。我们还考虑了未解析的双星/多星，这些星是通过光谱中与Gaia视差推断出的几何形状的偏差来识别的。这种二进制识别方法对于质量近似相等的未解析二进制特别有效，因此提供了一种有用的补充方式来识别未解析二进制或多星系统。我们提供了LAMOST DR5的光谱，消光，距离，发射线标记和16,002 OB星的二分类的目录。作为说明，我们调查了神秘的LB-1系统，刘等人。争论的焦点包括一颗B星和一个巨大的恒星质量黑洞。我们的结果表明LB-1是一个双星系统，其中包含两个亮度相当的发光恒星，而Gaia eDR3的视差进一步支持了这一结果。