Identifying spurious reduction artefacts in galaxy spectra is a challenge for large surveys. We present an algorithm for identifying and repairing residual spurious features in sky-subtracted galaxy spectra with application to the VIPERS survey. The algorithm uses principal component analysis (PCA) applied to the galaxy spectra in the observed frame to identify sky line residuals imprinted at characteristic wavelengths. We further model the galaxy spectra in the rest-frame using PCA to estimate the most probable continuum in the corrupted spectral regions, which are then repaired. We apply the method to 90,000 spectra from the VIPERS survey and compare the results with a subset where careful editing was performed by hand. We find that the automatic technique does an extremely good job in reproducing the time-consuming manual cleaning and does it in a uniform and objective manner across a large data sample. The mask data products produced in this work are released together with the VIPERS second public data release (PDR-2).
@article{arxiv.1612.01825,
title = {The VIMOS Public Extragalactic Redshift Survey (VIPERS): PCA-based automatic cleaning and reconstruction of survey spectra},
author = {A. Marchetti and B. Garilli and B. R. Granett and L. Guzzo and A. Iovino and M. Scodeggio and M. Bolzonella and S. de la Torre and U. Abbas and C. Adami and D. Bottini and A. Cappi and O. Cucciati and I. Davidzon and P. Franzetti and A. Fritz and J. Krywult and V. Le Brun and O. Le Fèvre and D. Maccagni and K. Małek and F. Marulli and M. Polletta and A. Pollo and L. A. M. Tasca and R. Tojeiro and D. Vergani and A. Zanichelli and S. Arnouts and J. Bel and E. Branchini and J. Coupon and G. De Lucia and O. Ilbert and T. Moutard and L. Moscardini and G. Zamorani},
journal= {arXiv preprint arXiv:1612.01825},
year = {2017}
}
Comments
Find the VIPERS data release at http://vipers.inaf.it