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arXiv · 1210.1837

Improved astrometry for the Bohannan & Epps catalogue

Ian D. Howarth
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Abstract

Aims: Accurate astrometry is required to reliably cross-match 20th-century catalogues against 21st-century surveys. The present work aims to provide such astrometry for the 625 entries of the Bohannan & Epps (BE74) catalogue of H$α$ emission-line stars. Methods: BE74 targets have been individually identified in digital images and, in most cases, unambiguously matched to entries in the UCAC4 astrometric catalogue. Results: Sub-arcsecond astrometry is now available for almost all BE74 stars. Several identification errors in the literature illustrate the perils of relying solely on positional coincidences using poorer-quality astrometry.

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Ian D. Howarth. 2012-10-05. Improved astrometry for the Bohannan & Epps catalogue. https://doi.org/10.1051/0004-6361%2F201220250

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