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arXiv · 1601.07162

NIR Tully-Fisher in the Zone of Avoidance. - II. 21 cm HI-line spectra of southern ZOA galaxies

Khaled Said·Renée C. Kraan-Korteweg·Lister Staveley-Smith·Wendy L. Williams·T. H. Jarrett·Christopher M. Springob
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Abstract

High-accuracy HI profiles and linewidths are presented for inclined ($(b/a)^o < 0.5$) spiral galaxies in the southern Zone of Avoidance (ZOA). These galaxies define a sample for use in the determinations of peculiar velocities using the near-infrared Tully-Fisher (TF) relation. The sample is based on the 394 HI-selected galaxies from the Parkes HI Zone of Avoidance survey (HIZOA). Follow-up narrow-band Parkes HI observations were obtained in 2010 and 2015 for 290 galaxies, while for the further 104 galaxies, sufficiently high signal-to-noise spectra were available from the original HIZOA data. All 394 spectra are reduced and parameterized in the same systematic way. Five different types of linewidth measurements were derived, and a Bayesian mixture model was used to derive conversion equations between these five widths. Of the selected and measure galaxies, 342 have adequate signal-to-noise (S/N $\geq$ 5) for use in TF distance estimation. The average value of the signal-to-noise ratio of the sample is 14.7. We present the HI parameters for these galaxies. The sample will allow a more accurate determination of the flow field in the southern ZOA which bisects dynamically important large-scale structures such as Puppis, the Great Attractor, and the Local Void.

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Khaled Said, Renée C. Kraan-Korteweg, Lister Staveley-Smith, Wendy L. Williams, T. H. Jarrett, Christopher M. Springob. 2016-01-26. NIR Tully-Fisher in the Zone of Avoidance. - II. 21 cm HI-line spectra of southern ZOA galaxies. https://doi.org/10.1093/mnras/stw105

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