Related papers: HI in Group Interactions: HCG 44
We apply a spectral stacking technique to Westerbork Synthesis Radio Telescope observations to measure the neutral atomic hydrogen content (HI) of nearby galaxies in and around galaxy groups at $z < 0.11$. Our sample includes 577…
We present 21-cm observations and models of the neutral hydrogen in NGC 4565, a nearby, edge-on spiral galaxy, as part of the Westerbork Hydrogen Accretion in LOcal GAlaxieS (HALOGAS) survey. These models provide insight concerning both the…
Here I present a brief review of interacting galaxy systems with extended low surface brightness (LSB) hydrogen tails and similar structures. Typically found in merging pairs, galaxy groups and clusters, HI features in galaxy surroundings…
Models of hierarchical galaxy formation predict that large numbers of low-mass, dark matter halos remain around galaxies today. These models predict an order of magnitude more halos than observed stellar satellites in the Local Group. One…
We present new Gemini spectra of 14 new objects found within the HI tails of Hickson Compact Groups 92 and 100. Nine of them are GALEX Far-UV (FUV) and Near-UV (NUV) sources. The spectra confirm that these objects are members of the compact…
Galaxies in compact groups tend to be deficient in neutral hydrogen compared to isolated galaxies of similar optical properties. In order to investigate the role played by a hot intragroup medium (IGM) for the removal and destruction of HI…
We present preliminary results from a study of the neutral hydrogen (HI) properties of an X-ray selected sample of nearby loose galaxy groups. This forms part of a multi-wavelength investigation (X-ray, optical and radio) of the formation…
Five galaxy groups with properties similar to those of the Local Group have been surveyed for HI clouds with the Arecibo Telescope. In total 300 pointings have been observed on grids of approximately 2.5 x 1.5 Mpc centred on the groups. The…
The dynamical evolution of the large (> 100 kpc), barred spiral galaxy NGC 6872 and its small companion IC 4970 in the southern group Pavo is investigated. We present N-body simulations with stars and gas and 21 cm HI observations carried…
A head-tail high-velocity cloud (HVC) is a neutral hydrogen halo cloud that appears to be interacting with the diffuse halo medium as evident by its compressed head trailed by a relatively diffuse tail. This paper presents a sample of 116…
We have observed the NGC 2403 group of galaxies using the Robert C. Byrd Green Bank Telescope (GBT) in a search for faint, extended neutral hydrogen clouds similar to the clouds found around the M81/M82 group, which is located approximately…
In a new HI imaging survey of Virgo galaxies (VIVA: VLA Imaging of Virgo galaxies in Atomic gas), we find 7 spiral galaxies with long HI tails. The morphology varies but all the tails are extended well beyond the optical radii on one side.…
We analyze line-of-sight atomic hydrogen (HI) line profiles of 31 nearby, low-mass galaxies selected from the Very Large Array - ACS Nearby Galaxy Survey Treasury (VLA-ANGST) and The HI Nearby Galaxy Survey (THINGS) to trace regions…
We study the hot and cold circum-galactic medium (CGM) of 86 galaxies of the cosmological, hydrodynamical simulation suite NIHAO. NIHAO allows a study of how the $z=0$ CGM varies across 5 orders of magnitude of stellar mass using OVI and HI…
The consortium for Galactic studies with the Arecibo L-band Feed Array (ALFA) is conducting a neutral hydrogen (HI) survey of the whole Arecibo sky (declination range from -1 to 38 degrees), with high angular (3.5') and velocity resolution…
Using archival data from ATCA, WSRT, and the VLA, we have analyzed the HI emission of 22 tidal tail regions of the Mullan et al. sample of pairwise interacting galaxies. We have measured the column densities, line-of-sight velocity…
We present a comprehensive study on the impact of the environment of compact galaxy groups on the evolution of their members using a multi-wavelength analysis, from the UV to the infrared, for a sample of 32 Hickson compact groups (HCGs)…
We present initial results from a deep neutral hydrogen (HI) survey of the HALOGAS galaxy sample, which includes the spiral galaxies NGC891, NGC925, NGC4414, and NGC4565, performed with the Robert C. Byrd Green Bank Telescope (GBT). The…
We have used V- and I- band images from the Hubble Space Telescope (HST) to identify compact stellar clusters within the tidal tails of twelve different interacting galaxies. The seventeen tails within our sample span a physical parameter…
Nearby Compact Groups of Galaxies (CGs) are very complex systems, tracing their history is a challenge (e.g. Stephan's Quintet). The presence of a diffuse X-rays emission that often peaks in the center of CGs shows that CGs are bound…