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arXiv · 1603.09438

MARZ: Manual and Automatic Redshifting Software

Samuel R. Hinton·Tamara M. Davis·Chris Lidman·Karl Glazebrook·Geraint F. Lewis
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Abstract

The Australian Dark Energy Survey (OzDES) is a 100-night spectroscopic survey underway on the Anglo-Australian Telescope using the fibre-fed 2-degree-field (2dF) spectrograph. We have developed a new redshifting application Marz with greater usability, flexibility, and the capacity to analyse a wider range of object types than the Runz software package previously used for redshifting spectra from 2dF. Marz is an open-source, client-based, Javascript web-application which provides an intuitive interface and powerful automatic matching capabilities on spectra generated from the AAOmega spectrograph to produce high quality spectroscopic redshift measurements. The software can be run interactively or via the command line, and is easily adaptable to other instruments and pipelines if conforming to the current FITS file standard is not possible. Behind the scenes, a modified version of the Autoz cross-correlation algorithm is used to match input spectra against a variety of stellar and galaxy templates, and automatic matching performance for OzDES spectra has increased from 54% (Runz) to 91% (Marz). Spectra not matched correctly by the automatic algorithm can be easily redshifted manually by cycling automatic results, manual template comparison, or marking spectral features.

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Samuel R. Hinton, Tamara M. Davis, Chris Lidman, Karl Glazebrook, Geraint F. Lewis. 2016-03-31. MARZ: Manual and Automatic Redshifting Software. https://doi.org/10.1016/j.ascom.2016.03.001

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