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Astrometric demands of fibre-input spectrographs for wide-field quasar redshift surveys

Peter R Newman
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Abstract

A potential problem with using wide-field multi-object spectrographs for quasar redshift surveys is the introduction of position-dependent selection effects into the survey catalogue because of variations in the observed signal-to-noise ratio (SNR) across the survey area. A function relating signal losses in instruments using optical fibre input to the fibre-to-image position error, the fibre diameter and the seeing conditions is given and plotted for a range of typical values of fibre sizes and seeing found in current instruments.

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Peter R Newman. 2000-09-18. Astrometric demands of fibre-input spectrographs for wide-field quasar redshift surveys. https://arxiv.org/abs/astro-ph/0009278

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