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A Catalogue of Field Horizontal Branch Stars Aligned with High Velocity Clouds

Christopher Thom·Brad K. Gibson·Norbert Christlieb
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Abstract

We present a catalogue of 430 Field Horizontal Branch (FHB) stars, selected from the Hamburg/ESO Survey (HES), which fortuitously align with high column density neutral hydrogen (HI) High-Velocity Cloud (HVC) gas. These stars are ideal candidates for absorption-line studies of HVCs, attempts at which have been made for almost 40 years with little success. A parent sample of 8321 HES FHB stars was used to extract HI spectra along each line-of-sight, using the HI Parkes All-Sky Survey. All lines-of-sight aligned with high velocity HI emission with peak brightness temperatures greater than 120mK were examined. The HI spectra of these 430 probes were visually screened and cross-referenced with several HVC catalogues. In a forthcoming paper, we report on the results of high-resolution spectroscopic observations of a sample of stars drawn from this catalogue.

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Christopher Thom, Brad K. Gibson, Norbert Christlieb. 2005-06-27. A Catalogue of Field Horizontal Branch Stars Aligned with High Velocity Clouds. https://doi.org/10.1086/444414

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