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arXiv · 1902.07300

A treatment procedure for GMOS/IFU data cubes: application to NGC 2835

Abstract

We present a set of treatment techniques for GMOS/IFU data cubes, including: correction of the differential atmospheric refraction; Butterworth spatial filtering, to remove high spatial-frequency noise; instrumental fingerprint removal; Richardson-Lucy deconvolution, to improve the spatial resolution of the observations. A comparison with HST images shows that the treatment techniques preserve the morphology of the spatial structures in the data cubes, without introducing distortions or ghost features. The treatment procedure applied to the data cube of the central region of the late-type galaxy NGC 2835 allowed the detection of a nuclear emitting region with emission-line ratios indicating a probable LINER, although the classifications of Transition Object or Seyfert galaxy cannot be discarded. Such a detection was not possible without the data treatment. This shows that the benefits provided by this treatment procedure are not merely cosmetic, but actually affect the quality of different types of analyses, like the determination of the fraction of galaxies, of different morphological types, with a central Seyfert/LINER/Transition object emission.

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R. B. Menezes, T. V. Ricci, J. E. Steiner, Patrícia da Silva, Fabricio Ferrari, B. W. Borges. 2019-02-19. A treatment procedure for GMOS/IFU data cubes: application to NGC 2835. https://doi.org/10.1093/mnras%2Fsty3337

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