SAMI-HI: the connection between global asymmetry in the ionised and neutral atomic hydrogen gas in galaxies

Abstract

Observations of the neutral atomic hydrogen (HI) gas in galaxies are predominantly spatially unresolved, in the form of a global HI spectral line. There has been substantial work on quantifying asymmetry in global HI spectra (`global HI asymmetry'), but due to being spatially unresolved, it remains unknown what physical regions of galaxies the asymmetry traces, and whether the other gas phases are affected. Using optical integral field spectrograph (IFS) observations from the Sydney AAO Multi-object IFS (SAMI) survey for which global HI spectra are also available (SAMI-HI), we study the connection between asymmetry in galaxies' ionised and neutral gas reservoirs to test if and how they can help us better understand the origin of global HI asymmetry. We reconstruct the global H$\alpha$ spectral line from the IFS observations and find that, while some global H$\alpha$ asymmetries can arise from disturbed ionised gas kinematics, the majority of asymmetric cases are driven by the distribution of H$\alpha$-emitting gas. When compared to the HI, we find no evidence for a relationship between the global H$\alpha$ and HI asymmetry. Further, a visual inspection reveals that cases where galaxies have qualitatively similar H$\alpha$ and HI spectral profiles can be spurious, with the similarity originating from an irregular 2D H$\alpha$ flux distribution. Our results highlight that comparisons between global H$\alpha$ and HI asymmetry are not straightforward, and that many global HI asymmetries trace disturbances that do not significantly impact the central regions of galaxies.

arXiv comment11 pages, 6 figures, 1 appendix, accepted for publication in MNRAS

References in corpus (72)

• The Sloan Digital Sky Survey: Technical Summary
• Galactic Stellar and Substellar Initial Mass Function
• The Dust Content and Opacity of Actively Star-Forming Galaxies
• The Seventh Data Release of the Sloan Digital Sky Survey
• Theoretical Modeling of Starburst Galaxies
• Parametric Recovery of Line-of-Sight Velocity Distributions from Absorption-Line Spectra of Galaxies via Penalized Likelihood
• Overview of the SDSS-IV MaNGA Survey: Mapping Nearby Galaxies at Apache Point Observatory
• A simple model to interpret the ultraviolet, optical and infrared emission from galaxies
• Galaxy and Mass Assembly (GAMA): survey diagnostics and core data release
• Evolutionary Stellar Population Synthesis with MILES. Part I: The Base Models and a New Line Index System
• Galaxy And Mass Assembly: Stellar Mass Estimates
• The Sydney-AAO Multi-object Integral field spectrograph (SAMI)
• The SAMI Galaxy Survey: instrument specification and target selection
• The Arecibo Legacy Fast ALFA Survey: The ALFALFA Extragalactic HI Source Catalog
• xGASS: Total cold gas scaling relations and molecular-to-atomic gas ratios of galaxies in the local Universe
• Little Things
• Evolutionary Stellar Population Synthesis at High Spectral Resolution: Optical Wavelengths
• New Lessons from the HI Size-Mass Relation of Galaxies
• WALLABY -- An SKA Pathfinder HI Survey
• The Dawes Review 9: The role of cold gas stripping on the star formation quenching of satellite galaxies
• Performance of AAOmega: the AAT multi-purpose fibre-fed spectrograph
• The cold interstellar medium of galaxies in the Local Universe
• A Universal Neutral Gas Profile for Nearby Disk Galaxies
• Lopsided spiral galaxies: evidence for gas accretion
• The SAMI Galaxy Survey: Early Data Release
• GAMA/H-ATLAS: A meta-analysis of SFR indicators - comprehensive measures of the SFR-M* relation and Cosmic Star Formation History at z < 0.4
• Jellyfish galaxies with the IllustrisTNG simulations: I. Gas-stripping phenomena in the full cosmological context
• Galaxy And Mass Assembly (GAMA): The galaxy stellar mass function to $z=0.1$ from the r-band selected equatorial regions
• Focal ratio degradation in lightly-fused hexabundles
• An observational and theoretical view of the radial distribution of HI gas in galaxies
• The Arecibo Legacy Fast ALFA Survey: IV. Strategies for Signal Identification and Survey Catalog Reliability
• The SAMI Galaxy Survey: the third and final data release
• The KMOS Redshift One Spectroscopic Survey (KROSS): the origin of disk turbulence in z~0.9 star-forming galaxies
• The SAMI Galaxy Survey: Cubism and covariance, putting round pegs into square holes
• NGC 4569: recent evidence for a past ram pressure stripping event
• LZIFU: an emission-line fitting toolkit for integral field spectroscopy data
• The environmental dependence of HI in galaxies in the EAGLE simulations
• The SAMI Galaxy Survey: The cluster redshift survey, target selection and cluster properties
• HI-MaNGA: HI Followup for the MaNGA Survey
• The busy function: a new analytic function for describing the integrated 21-cm spectral profile of galaxies
• The AMIGA sample of isolated galaxies: VIII. The rate of asymmetric HI profiles in spiral galaxies
• The SAMI Galaxy Survey: Stellar and gas misalignments and the origin of gas in nearby galaxies
• HI-MaNGA: Tracing the physics of the neutral and ionized ISM with the second data release
• Lopsidedness in WHISP galaxies: II. Morphological lopsidedness
• The SAMI Galaxy Survey: stellar population and structural trends across the Fundamental Plane
• WALLABY Pilot Survey: Public release of HI data for almost 600 galaxies from phase 1 of ASKAP pilot observations
• The Photometric and Kinematic Structure of Face-On Disk Galaxies. I. Sample Definition, H-alpha Integral Field Spectroscopy, and HI Line-Widths
• Origin of Disc Lopsidedness in the Eridanus Group of Galaxies
• Lopsidedness in WHISP galaxies: I. Rotation curves and kinematic lopsidedness
• Abell 1367: a high fraction of late-type galaxies displaying HI morphological and kinematic perturbations
• Tidally induced warps of spiral galaxies in IllustrisTNG
• xGASS: Robust quantification of asymmetries in global HI spectra and their relationship to environmental processes
• The SAMI Galaxy Survey: Asymmetry in Gas Kinematics and its links to Stellar Mass and Star Formation
• SDSS-IV MaNGA: Kinematic Asymmetry as An Indicator of Galaxy Interaction in Paired Galaxies
• On the Determination of Rotation Velocity and Dynamical Mass of Galaxies Based on Integrated H I Spectra
• Spatial and Kinematical Lopsidedness of Atomic Hydrogen in the Ursa Major Group of Galaxies
• Enhanced HI profile asymmetries in close galaxy pairs
• Global HI asymmetries in IllustrisTNG: a diversity of physical processes disturb the cold gas in galaxies
• The SAMI Galaxy Survey: gas content and interaction as the drivers of kinematic asymmetry
• The SAMI Galaxy Survey: The Low-Redshift Stellar Mass Tully-Fisher Relation
• WALLABY Pilot Survey: First Look at the Hydra I Cluster and Ram Pressure Stripping of ESO 501-G075
• Systematically Asymmetric: A comparison of \hi\ profile asymmetries in real and simulated galaxies
• Genesis of morpho-kinematic lopsidedness in minor merger of galaxies
• The major mechanism to drive turbulence in star-forming galaxies
• Massive Galaxy Mergers Have Distinctive Global HI Profiles
• Lopsided galactic disks in IllustrisTNG
• On the relationship between gas content, star-formation, and global HI asymmetry of galaxies on the star-forming main-sequence
• HI Deficiencies and Asymmetries in HIPASS Galaxies
• Unveiling the environment and faint features of the isolated galaxy CIG 96 with deep optical and HI observations
• SAMI-HI: The HI view of the H$\alpha$ Tully-Fisher relation and data release
• ASymba: HI global profile asymmetries in the Simba simulation
• Using EAGLE simulations to study the effect of observational constraints on the determination of HI asymmetries in galaxies

Cited by in corpus (3)

• IllustrisTNG in the HSC-SSP: image data release and the major role of mini mergers as drivers of asymmetry and star formation
• WALLABY Pilot Survey & ASymba: Comparing HI Detection Asymmetries to the SIMBA Simulation
• Comparison of Global HI and H$\alpha$ Line Profiles in MaNGA Galaxy Pairs with FAST