相关论文: Detection of a slow HI bar in the dwarf irregular …
We examine the bar instability in galactic models with an exponential disk and a cuspy dark matter (DM) halo with a Navarro-Frenk-White (NFW) cosmological density profile. We construct equilibrium models from a 3-integral composite…
We estimate the power spectrum of HI intensity fluctuations for a sample of 8 galaxies (7 dwarf and one spiral). The power spectrum can be fitted to a power law P_HI(U) = A U^\alpha for 6 of these galaxies, indicating turbulence is…
Here we present a kinematic study of the Galactic halo out to a radius of $\sim$ 60 kpc, using 4664 blue horizontal branch (BHB) stars selected from the SDSS/SEGUE survey, to determine key dynamical properties. Using a maximum likelihood…
The thickness of the neutral hydrogen layer, coupled with the rotation curve, traces the outer dark matter potential. We estimate the amplitude of the flaring in spiral galaxies from a 3D model of the HI gas. Warps in particular are…
We present the HI galaxy observation results of the FATHOMER (FAst neuTral HydrOgen intensity Mapping ExpeRiment), a pilot drift scan survey by the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The survey comprises 28 hours…
The unusually large "dwarf" galaxy Crater II, with its small velocity dispersion, $\simeq 3$ km/s, defies expectations that low mass galaxies should be small and dense. We combine the latest stellar and velocity dispersion profiles finding…
We present new constraints on the density profiles of dark matter (DM) halos in seven nearby dwarf galaxies from measurements of their integrated stellar light and gas kinematics. The gas kinematics of low mass galaxies frequently suggest…
Abridged. Context. The metal content of dwarf galaxies and the metal enrichment of the intergalactic medium both suggest that mass loss from galaxies is a significant factor for the chemical evolution history of galaxies, in particular of…
We present a detailed analysis of the neutral hydrogen kinematics of 12 nearby dwarf irregular galaxies observed as part of the Local Volume HI Survey (LVHIS) conducted at the Australia Telescope Compact Array. For each galaxy we measure…
Stellar bars are the most common non-axisymmetric structures in galaxies and their impact on the evolution of disc galaxies at all cosmological times can be significant. Classical theory predicts that stellar discs are stabilized against…
Among the most fundamental properties of a dark matter halo is its density profile. Motivated by the recent proposal by Garc\'ia et al. [R. Garc\'ia et. al., MNRAS 521, 2464 (2023)] to define a dynamical halo as the collection of orbiting…
DDO68 (UGC5340) is an unusual dwarf galaxy with extremely low gas metallicity (12+log(O/H) = 7.14) residing in the nearby Lynx-Cancer void. Despite its apparent isolation, it shows both optical and HI morphological evidence for strong tidal…
(abridged) DYNAMO is a multi-wavelength, spatially-resolved survey of local ($z \sim 0.1$) star-forming galaxies designed to study evolution through comparison with samples at z~2. Half of the sample has integrated H-alpha luminosities of…
Current theories of dynamical friction on galactic bars are based either on linear perturbation theory, which is valid only in the fast limit where the bar changes its pattern speed rapidly, or on adiabatic theory, which is applicable only…
A population of discrete HI clouds in the halo of the inner Galaxy has been discovered in 21cm observations made with the Green Bank Telescope. The halo clouds are seen up to 1.5 kpc from the Galactic plane at many longitudes. Their…
The MaNGA project has obtained IFU data for several thousand nearby galaxies, including barred galaxies. With the two dimensional spectral and kinematic information provided by IFUs, we can measure the pattern speed of a barred galaxy,…
NGC 2915 is a blue compact dwarf galaxy embedded in an extended, low surface brightness HI disk exhibiting a two-armed spiral structure and a central bar-like component. Commonly accepted mechanisms are unable to explain the existence of…
We investigate the velocity field derived from HI measurements of the irregular galaxy ESO 358-60 using the Velocity Ring Model (VRM) method. This technique, which assumes a coplanar disk, allows us to reconstruct coarse-grained maps of…
The dynamical stability of disk galaxies is sensitive to whether their anomalous rotation curves are caused by dark matter halos or Milgromian Dynamics (MOND). We investigate this by setting up a MOND model of M33. We first simulate it in…
An accurate knowledge of the dark matter distribution in the Milky Way is of crucial importance for galaxy formation studies and current searches for particle dark matter. In this paper we set new dynamical constraints on the Galactic dark…