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arXiv · 2510.25871

New Pipeline for Efficient Analysis of Large Spectroscopic Samples of OB Stars

PA Crowther·JM Bestenlehner
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Abstract

We present a new spectroscopic pipeline designed to analyse large numbers of hot massive stars homogeneously. The pipeline has been developed to utilise large grids of FASTWIND non-LTE, line blanketed models in which spherical geometry is adopted, and uniquely incorporates model errors. The pipeline has been applied to three contemporary datasets involving Very Large Telescope spectroscopy of OB stars in the Magellanic Clouds, namely the VLT FLAMES Tarantula Survey (VFTS), XShooting-ULLYSES (XShootU) and Binaries at Low Metallicity (BLOeM). We find satisfactory agreement with previous detailed temperatures and surface gravities, although strong nebular contamination, binarity and disk emission from OBe stars are problematic for automatic pipelines, requiring visual inspection of fits. The tool has been incorporated into the pipeline for the VISTA/4MOST pipeline.

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PA Crowther, JM Bestenlehner. 2025-10-29. New Pipeline for Efficient Analysis of Large Spectroscopic Samples of OB Stars. https://arxiv.org/abs/2510.25871

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