相关论文: KAT-7 Science Verification: Using HI Observations …

We present HI observations of the Sculptor Group starburst spiral galaxy NGC 253, obtained with the Karoo Array Telescope (KAT-7). KAT-7 is a pathfinder for the SKA precursor MeerKAT, under construction. The short baselines and low system…

New high resolution CFHT Fabry-Perot data, combined with published VLA 21 cm observations are used to determine the mass distribution of NGC 3109 and IC 2574. The multi-wavelength rotation curves allow to test with confidence different dark…

We present high sensitivity HI observations of NGC 6822, obtained with the Karoo Array Telescope (KAT-7). We study the kinematics, the mass distribution, and the star formation thresholds. The KAT-7 short baselines and low system…

We present early observations of 20 galaxies in the MHONGOOSE survey galaxies using KAT-7, the GBT, and MeerKAT. We present the best calibrators for five of the MHONGOOSE galaxies observed with the KAT-7, and search for signs of gas…

We present new KAT-7 observations of the neutral hydrogen (HI) spectral line, and polarized radio continuum emission, in the grand design spiral M83. These observations provide a sensitive probe of the outer disk structure and kinematics,…

The seven-dish KAT-7 array was built as an engineering test-bed for the 64-dish Karoo Array Telescope, known as MeerKAT, which is the South African precursor of the Square Kilometre Array (SKA). KAT-7 and MeerKAT are located close to the…

MHONGOOSE is a deep survey of the neutral hydrogen distribution in a representative sample of 30 nearby disk and dwarf galaxies with HI masses from 10^6 to ~10^{11} M_sun, and luminosities from M_R ~ -12 to M_R ~ -22. The sample is selected…

We present HI observations of the elliptical galaxy NGC 2974, obtained with the Very Large Array. These observations reveal that the previously detected HI disc in this galaxy (Kim et al. 1988) is in fact a ring. By studying the harmonic…

As part of a long-term project to revisit the kinematics and dynamics of the large disc galaxies of the Local Group, we present the first deep, wide-field (42' x 56') 3D-spectroscopic survey of the ionized gas disc of Messier 33.…

We present 21-cm observations and models of the HI kinematics and distribution of NGC 4244, a nearby edge-on Scd galaxy observed as part of the Westerbork Hydrogen Accretion in LOcal GAlaxieS (HALOGAS) survey. Our models give insight into…

We test cosmological models of structure formation using the rotation curve of the nearest spiral galaxy, M31, determined using a recent deep, full-disk 21-cm imaging survey smoothed to 466 pc resolution. We fit a tilted ring model to the…

We present new HI observations of the nearby dwarf galaxy NGC 3741. This galaxy has an extremely extended HI disk, which allows us to trace the rotation curve out to unprecedented distances in terms of the optical disk: we reach 42 B-band…

As part of a continuing survey of nearby galaxies, we have mapped the neutral gas content of the low surface brightness, Magellanic-type galaxy NGC 3109 --- and its environment, including the Antlia dwarf galaxy --- at unprecedented…

We use recent very extended HI kinematics (out to 48 kpc) along with previous H$\alpha$ kinematics of the spiral galaxy NGC 3198 in order to derive its distribution of dark matter (DM). First, we used a chi-square method to model the…

Mass models of 15 nearby dwarf and spiral galaxies are presented. The galaxies are selected to be homogeneous in terms of the method used to determine their distances, the sampling of their rotation curves (RCs) and the mass-to-light ratio…

We present the analysis of new, deep HI observations of the spiral galaxy NGC 3198, as part of the HALOGAS (Westerbork Hydrogen Accretion in LOcal GAlaxieS) survey, with the main aim of investigating the presence, amount, morphology and…

Using the example of the Sd galaxy NGC 5585, it is shown that high resolution 2-D HII kinematical data are necessary to determine accurately the parameters of the mass distribution in spirals. New CFHT Fabry-Perot Halpha observations are…

We map the Hi distribution of galaxies in a $\sim 1.5^\circ \times 2.5^\circ$ region located at the virial radius south of the Virgo cluster using the KAT$-$7 and the WSRT interferometers. Because of the different beam sizes of the two…

We propose a complementary and fast approach to study galaxy rotation curves directly from the sample data, instead of individual fits. With this approach, some relevant tests can be done analytically. It is based on a dimensionless…

We construct a mass model for the spiral lens galaxy 2237+0305, at redshift z_l=0.04, based on gravitational-lensing constraints, HI rotation, and new stellar-kinematic information, based on data taken with the ESI spectrograph on the 10m…