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The Local Volume HI Survey (LVHIS) 3 Mon. Not. R. Astron. Soc. 000, 000–000 (0000) Printed 23 April 2019 (MN LATEX style file v2.2) The Local Volume HI Survey (LVHIS)⋆ B¨arbel S. Koribalski1, Jing Wang1,6, P. Kamphuis1,7, T. Westmeier2, L. Staveley-Smith2, S.-H. Oh2,8, A.R.´ L´opez-S´anchez3, O. I. Wong2, J. Ott4, W.J.G. de Blok5, and L. Shao1 1Australia Telescope National Facility, CSIRO Astronomy & Space Science, P.O. Box 76, Epping, NSW 1710, Australia 2International Centre for Radio Astronomy Research (ICRAR), University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia 3Australian Astronomical Observatory, 105 Delhi Road, North Ryde, NSW 2113, Australia 4National Radio Astronomy Observatory, P.O. Box O, 1003 Lopezville Road, Socorro, NM 87801, USA 5Netherlands Institute for Radio Astronomy, Postbus 2, 7990 AA Dwingeloo, The Netherlands 6Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, China 7National Centre for Radio Astrophysics, TIFR, Ganeshkhind, Pune 411007, India 8Korea Astronomy and Space Science Institute (KASI), Daedeokdae-ro 776, Yuseong-gu, Daejeon 34055, Republic of Korea Received date; accepted date ABSTRACT The ‘Local Volume HI Survey’ (LVHIS) comprises deep H i spectral line and 20-cm radio continuum observations of 82 nearby, gas-rich galaxies, supplemented by multi- wavelength images. Our sample consists of all galaxies with Local Group velocities vLG < 550 kms−1 or distances D < 10 Mpc that are detected in the H i Parkes All Sky Survey (HIPASS). Using full synthesis observations in at least three configurations of the Australia Telescope Compact Array (ATCA), we obtain detailed H i maps for a ◦ complete sample of gas-rich galaxies with δ ∼< − 30 . Here we present a comprehen- sive LVHIS galaxy atlas, including the overall gas distribution, mean velocity field, velocity dispersion and position-velocity diagrams, together with a homogeneous set of measured and derived galaxy properties. Our primary goal is to investigate the H i morphologies, kinematics and environment at high resolution and sensitivity. LVHIS galaxies represent a wide range of morphologies and sizes; our measured H i masses 7 10 range from ∼10 to 10 M⊙, based on independent distance estimates. The LVHIS galaxy atlas (incl. FITS files) is available on-line. Key words: surveys — galaxies: dwarf — galaxies: kinematics and dynamics — galaxies: spiral — galaxies: structure — radio lines: galaxies. arXiv:1904.09648v1 [astro-ph.GA] 21 Apr 2019 1 INTRODUCTION namics and star formation with respect to their surround- ings. The ‘Local Volume’ (LV), defined here as the sphere of ra- dius 10 Mpc centered on the Local Group (LG), includes Our long-term aim is to obtain high-resolution H i maps more than 500 known galaxies, many of which congregate in of all LV galaxies and measure their properties in a homo- well-known groups. Most prominent in the southern hemi- geneous and unbiased way. Wang et al. (2016), for exam- sphere are the relatively loose Sculptor Group and the more ple, present H i diameters (DHI) of over 500 nearby galaxies compact Centaurus A Group. Together, their gas-rich mem- −2 measured out to an H i mass (MHI) density of 1 M⊙ pc bers comprise about half of the ‘Local Volume HI Sur- and discuss the tightness of the MHI-DHI relation. Large H i vey’ (LVHIS) galaxy sample presented here. With accu- projects with radio interferometers, which have targeted LV rate distances available for the majority of the LV galax- galaxies, are listed in Table 1. The ‘Faint Irregular Galax- ies (Karachentsev et al. 2013, hereafter K13, and references ies GMRT Survey’ (FIGGS) by Begum et al. (2008), which therein), it is now possible to study their morphologies, dy- contains H i results for ∼60 dwarf irregular LV galaxies, is the largest H i study of nearby galaxies with the Gi- ant Meterwave Radio Telescope (GMRT). The most promi- i ⋆ The observations were obtained with the Australia Telescope nent Very Large Array (VLA) H projects are ‘The HI which is funded by the Commonwealth of Australia for oper- Nearby Galaxy Survey’ (THINGS; Walter et al. 2008), Little ations as a National Facility managed by CSIRO. - E-mail: THINGS (Hunter et al. 2012), and VLA-ANGST (Ott et al. [email protected] 2012). H i galaxy surveys with the Westerbork Synthesis Ra- c 0000 RAS 2 B.S. Koribalski et al. dio Telescope (WSRT) include the ‘Westerbork HI Survey of Furthermore, three tidal dwarf galaxy candidates with H i 7 Irregular and Spiral Galaxies’ (WHISP; van der Hulst et al. masses around 10 M⊙ have been discovered within the ex- 2001) and HALOGAS (Heald et al. 2011). Interferometric trapolated spiral/tidal arm of NGC 1512. Another example H i surveys of galaxies beyond the Local Volume include the is the multi-wavelength study of the dIrr galaxies NGC 5408 VLA Imaging of Virgo in Atomic Gas (VIVA; Chung et al. and IC 4662 by van Eymeren et al. (2010), who find H i discs 2009), ATLAS-3D, targeting 166 early-type galaxies (Serra extending well beyond their stellar extent. et al. 2012), and BlueDisks (Wang et al. 2013). The LVHIS project comprises the largest number of Our paper is structured as follows: in Section 2 we in- nearby galaxies studied with the Australia Telescope Com- troduce the LVHIS galaxy sample, followed by a description pact Array (ATCA); an overview and H i galaxy atlas are of the ATCA observations and data reduction in Section 3. presented in this paper. Previous publications based on Our results are presented in Sections 4 & 5 with the lat- LVHIS include Koribalski (2008, 2010, 2015, 2017), Bonne ter containing short paragraphs for all LVHIS galaxies and (2008), Koribalski & L´opez-S´anchez (2009), van Eymeren et associated galaxies. This is followed by our summary and al. (2008, 2009c, 2010), Kirby et al. (2012), L´opez-S´anchez outlook in Section 6. In the on-line Appendix we present et al. (2008, 2012, 2015), Johnson et al. (2015), Kamphuis the H i moment maps and position-velocity (pv) diagrams et al. (2015), Wang et al. (2016, 2017), and Oh et al. (2018). for the majority of LVHIS galaxies. The first catalog of LV galaxies was presented by Kraan- Korteweg & Tammann (1979) and contained 179 galaxies −1 2 THE LVHIS GALAXY SAMPLE with Local Group velocities, vLG, less than 500 km s . More recently, the LV sample defined by Karachentsev et The ‘Local Volume HI Survey’ (LVHIS)1 comprises deep in- −1 i al. (2004) included 451 galaxies with vLG < 550 km s or terferometric H spectral line and 20-cm radio continuum independent distance D < 10 Mpc. A further expansion observations of a complete sample of nearby, gas-rich galax- −1 of the volume (vLG < 600 km s or D < 11 Mpc) led to ies and their surroundings. Following Karachentsev et al. −1 the most recent nearby galaxy catalog (K13; available at (2004), we selected galaxies with vLG < 550 km s or, when www.sao.ru/lv/lvgdb) which contains 869 galaxies. Of these, available, independently determined distances of D < 10 only 261 galaxies (30%) lie in the southern sky. Fig. 1 shows Mpc. To enable high-resolution H i studies of LV galax- the locations of the LVHIS galaxies in the southern sky. ies with the Australia Telescope Compact Array (ATCA), we also require the selected galaxies to have declinations < ◦ i The H i sizes of known LV galaxies cover more than two δ ∼ − 30 and be detected in the H Parkes All Sky Survey orders of magnitude, ranging from low-mass dwarf galax- (HIPASS). This ensures that our target galaxies are bright ies with diameters of less than 500 pc (e.g., Leo T, Ryan- enough for a detailed study of their H i gas distribution and Weber et al. 2008) to grand-design spirals with H i diameters dynamics with a reasonably symmetric synthesized beam. of nearly 100 kpc, e.g., Circinus (For et al. 2012) and M 83 Applying these criteria leads to an ATCA sample of 82 LV (Koribalski 2015, 2017). Consequently, their H i masses span galaxies. Fig. 2 shows the HIPASS vLG of all LVHIS galaxies more than four orders of magnitudes, ranging from a few against their best available distances. 5 10 times 10 M⊙ to 10 M⊙ (Wang et al. 2016). The major- ity of LV galaxies are dwarf galaxies; their morphologies — usually defined in the optical regime — range from the typ- 2.1 LVHIS — Optical Galaxy Properties ically gas-poor elliptical (dE) and spheroidal (dSph) dwarfs The optical properties of LVHIS galaxies, as obtained from to gas-rich irregular (dIrr), Magellanic (dM) and blue com- the literature, are given in Table 2. Once multi-wavelength pact dwarfs (BCD). In between sit the class of dwarf tran- images from the SkyMapper Southern Sky Survey and the sitional galaxies (dSph/dIrr), many of which show H i gas Large Synoptic Survey Telescope (LSST) are available, it offset from their stellar disc (e.g., Phoenix, St-Germain et will be possible to obtain a homogeneous set of optical prop- al. 1999). erties to complement the H i properties of all LVHIS galaxies. The Table 2 columns are: Col. (1+2) HIPASS and optical Our primary goal is to obtain detailed H i gas distribu- galaxy name; Col. (3) best available galaxy distance, D, with tions of LV galaxies, analyse their structure and gas kine- the reference given in Section 5 (also available from K13 and matics, measure their overall H i extent, and search for com- references therein); Col. (4) morphological type (from RC3, panions. Furthermore, we investigate the influence of the de Vaucouleurs et al.
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