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arXiv · 2506.14346

Measurements of the Diffuse Interstellar Bands at 5780, 5797, and 6614 Å in the Hot Stellar Spectra of the LAMOST LRS DR10

Abstract

Diffuse Interstellar Bands (DIBs) are crucial tracers of the interstellar medium (ISM), yet their carriers remain poorly understood. While large-scale surveys have advanced DIB studies in cool stellar spectra, measurements in hot stellar spectra are still limited. Using 287 277 high signal-to-noise (S/N $>$ 50) hot stellar spectra from the tenth data release of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope low-resolution spectroscopic survey (LAMOST LRS DR10), we systematically measured the three prominent optical DIBs at 5780, 5797, and 6614 Å. We published three catalogs containing 285 103, 279 195, and 281 146 valid measurements for the DIBs at 5780, 5797, and 6614 Å, respectively. Among them, 112 479, 25 232, and 71 048 are high-quality samples after rigorous quality control. To our knowledge, these are the largest hot-star DIB datasets in the northern sky. The catalogs provide spectral metadata, added astrometeric information, DIB profiles, and quality metrics. Our methodology and open-source pipeline ensure reproducibility, while the scale and precision of the data support future statistical studies. We anticipate that these catalogs will highlight the LAMOST's role in advancing DIB research and deepening our understanding of the ISM.

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Xiao-Xiao Ma, A-Li Luo, Jian-Jun Chen, Jing Chen, Jun-Chao Liang. 2025-06-17. Measurements of the Diffuse Interstellar Bands at 5780, 5797, and 6614 Å in the Hot Stellar Spectra of the LAMOST LRS DR10. https://arxiv.org/abs/2506.14346

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