Abstract
An automated method to search for metal line absorption systems in low and medium resolution QSO spectra is presented. The method is based on pattern recognition in noisy data: it compares rectified QSO spectra with an input absorption line pattern minimizing X 2 between model and data. The best candidate for a z system is chosen among the minima of the curve x 2=x 2(z) and can be subtracted if weaker systems are to be searched for. A modified version of the X 2 test has been developed in order to compute the probability of finding a system by chance. The method has proved to be successful by detecting 43 metal absorption systems in about 200 low resolution (FWHM≈25Å) QSO spectra of the Hamburg-ESO Survey with S/N≈40–50 and emission redshifts 0.33 ≤ zem ≤ 3.06.
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© 1995 Springer-Verlag Berlin Heidelberg
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López, S., Wisotzki, L. (1995). Automated Search for Absorption Systems in Low Resolution QSO Spectra. In: Meylan, G. (eds) QSO Absorption Lines. ESO Astrophysics Symposia. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-49458-4_34
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DOI: https://doi.org/10.1007/978-3-540-49458-4_34
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-662-22373-4
Online ISBN: 978-3-540-49458-4
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