Related papers: NGC 3310, a galaxy merger?
Hubble Space Telescope images of the galaxies NGC 2207 and IC 2163 show star formation and dust structures in a system that has experienced a recent grazing encounter. Tidal forces from NGC 2207 compressed and elongated the disk of IC 2163,…
Can the present dynamics of spiral galaxies tell us something about the merging history, the formation and evolution of disks? Galaxy interactions thicken or destroy disks; the simultaneous presence of thick and thin disks is a tracer of…
Mass estimates of a spiral galaxy derived from its rotation curve must account for the galaxy's past accretion history. There are several lines of evidence indicating that M31 experienced a major merger 2 to 3 Gyr ago. Here, we have…
We report a new high-sensitivity HI mapping observation of the NGC 5055 galaxy group over an area of $1.^\circ5\times0.^\circ75$ with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). Our observation reveals that the warped…
Star counts, obtained from a 2 x 2 degree area centered on NGC 6822 have revealed an optical image of this galaxy composed of two components: in addition to the well-known HI disk with its young stellar component, there is a spheroidal…
We revealed the detailed structure of a vastly extended H$\alpha$-emitting nebula ("H$\alpha$ nebula") surrounding the starburst/merging galaxy NGC 6240 by deep narrow-band imaging observations with the Subaru Suprime-Cam. The extent of the…
We present matched-resolution maps of HI and CO emission in the Virgo Cluster spiral NGC 4647. The galaxy shows a mild kinematic disturbance in which one side of the rotation curve flattens but the other side continues to rise. This…
We present high-quality aperture synthesis observations of the neutral hydrogen distribution in a sample of five galactic systems believed to be involved in progressive stages of merging: Arp295, NGC4676, NGC520, NGC3921, and NGC7252. These…
We present a new scenario in which massive intragroup HI clouds are the high-density parts of large HI rings/arcs formed by dynamical interaction between galaxy groups and gas-rich, low surface brightness (LSB) galaxies with extended gas…
We present results from GMRT HI 21 cm line observations of the interacting galaxy pair Arp 181 (NGC 3212 and NGC 3215) at z =0.032. We find almost all of the detected HI (90%) displaced well beyond the optical disks of the pair with the…
Taking a clue from the pair of HI supershells found in the Scd galaxy NGC 3556 (M 108), we propose a new mechanism for the origin of HI supershells in gas-rich massive galaxies. In this scenario, the two supershells were inflated out of the…
Extended HI structures around galaxies are of prime importance to probe galaxy formation scenarios. The giant HI ring in the Leo group is one of the largest and most intriguing HI structures in the nearby Universe. Whether it consists of…
As part of an on-going radio supernova monitoring program, we have discovered a variable, compact steep spectrum radio source ~65 arcsec (~4 kpc) from the centre of the starburst galaxy NGC 3310. If the source is at the distance of NGC…
We numerically investigate stellar and gaseous dynamical evolution of mergers between five identical late-type disk galaxies with the special emphasis on star formation history and chemical evolution of multiple galaxy mergers. We found…
Numerical simulations of minor mergers predict little enhancement in the global star formation activity. However, it is still unclear the impact they have on the chemical state of the whole galaxy and on the mass build-up in the galaxy…
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…
We present VLA \ion{H}{1} and optical spectra of the peculiar galaxy Arp~10. Originally believed to be an example of a classical colliding ring galaxy with multiple rings, the new observations show a large disturbed neutral hydrogen disk…
New ALMA CO, HCO+, and 100 GHz continuum observations and Gemini NIFS K-band spectra are combined with previous radio to X-ray data to study Feature i, a highly luminous starburst clump on an outer arm of the interacting galaxy NGC 2207.…
We present the first 3D spectroscopic observations of a nearby HI detected poststarburst, or E+A, galaxy, SDSS J230743.41+152558.4, obtained with the VIMOS IFU spectrograph at ESO VLT. Using the NBursts full spectral fitting technique, we…
We present our multiwavelength analysis of a prototype \HI-excess galaxy, GASS 3505, selected based on having a large gas content ($M_{\rm HI} = 10^{9.9}$ \msun) compared to its little associated star formation activity ($\sim$0.1 \msun\…