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- ID:
- ivo://CDS.VizieR/J/A+AS/139/1
- Title:
- HI in Byurakan blue compact galaxies
- Short Name:
- J/A+AS/139/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a neutral hydrogen survey of 79 galaxies from a statistical sample of 88 Blue Compact Galaxies (BCGs) selected from the First and Second Byurakan objective prism surveys to have a HII region-like spectrum, an equivalent width of the [O III] {lambda}5007 line larger than ~50{AA}, and a velocity <=6000km/s. The detection rate for the statistical sample is 74%. HI masses range between 4x10^7^M_{sun}_ and 5x10^9^M_{sun}_ with the HI mass distribution peaking at 3x10^8^M_{sun}_. The full width at half-maximum of the HI profile varies between ~30km/s and 160km/s, with a mean of ~92km/s. These small widths are characteristic of dwarf galaxies. For comparison, we have also observed an additional 92 BCGs with weaker star formation and/or larger distances, and/or interesting astrophysical properties. These in general have larger widths and HI masses.
- ID:
- ivo://CDS.VizieR/J/A+A/506/677
- Title:
- HI in Local Supercluster dwarf galaxies
- Short Name:
- J/A+A/506/677
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have observed 71 dwarf galaxies of low surface brightness using the 100-m radio telescope at Effelsberg in a search for new members of 27 northern galaxy groups with characteristic distances of 8 to 15Mpc. We present radial velocities, HI-fluxes, and HI line widths for 17 detected galaxies as well as upper limits for the remaining undetected objects.
- ID:
- ivo://CDS.VizieR/J/A+A/604/A43
- Title:
- HI in nearby radio sources
- Short Name:
- J/A+A/604/A43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of the properties of neutral hydrogen (HI) in 248 nearby (0.02<z<0.25) radio galaxies with S_1.4GHz_>30mJy and for which optical spectroscopy is available. The observations were carried out with the Westerbork Synthesis Radio Telescope as the last large project before the upgrade of the telescope with phased array feed receivers (Apertif). The sample covers almost four orders of magnitude in radio power from logP_1.4GHz_=22.5W/Hz and 26.2W/Hz. We detect HI in absorption in 27%+/-5.5% of the objects. The detections are found over the full range of radio power. However, the distribution and kinematics of the absorbing HI gas appear to depend on radio power, the properties of the radio continuum emission, and the dust content of the sources. Among the sources where HI is detected, gas with kinematics deviating from regular rotation is more likely found as the radio power increases.In the great majority of these cases, the HI profile is asymmetric with a significant blue-shifted component. This is particularly common for sources with logP_1.4GHz_>24W/Hz, where the radio emission is small, possibly because these radio sources are young. The same is found for sources that are bright in the mid-infrared, i.e. sources rich in heated dust.In these sources, the HI is outflowing likely under the effect of the interaction with the radio emission. Conversely, in dust-poor galaxies, and in sources with extended radio emission, at all radio powers we only detect HI distributed in a rotating disk. Stacking experiments show that in sources for which we do not detect HI in absorption directly, the HI has a column density that is lower than 3.5x10^17^(T_spin_/c_f_)cm^-2^. We use our results to predict the number and type of HI absorption lines that will be detected by the upcoming surveys of the Square Kilometre Array precursors and pathfinders (Apertif, MeerKAT, and ASKAP).
- ID:
- ivo://CDS.VizieR/J/A+A/430/373
- Title:
- HI lines in 586 galaxies
- Short Name:
- J/A+A/430/373
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents 586 new 21-cm neutral hydrogen line measurements carried out with the FORT receiver of the meridian transit Nancay radiotelescope in the period July 2000 - March 2003. This observational programme is part of a larger project aiming at collecting an exhaustive and magnitude-complete HI extragalactic catalogue for Tully-Fisher applications. It is associated with the building of the MIGALE spectroscopic archive and database. http://klun.obs-nancay.fr, http://http://www.sai.msu.su/migale/
- ID:
- ivo://CDS.VizieR/J/A+A/627/A106
- Title:
- HI observations of AT 2018cow
- Short Name:
- J/A+A/627/A106
- Date:
- 23 Mar 2022 16:27:48
- Publisher:
- CDS
- Description:
- Unusual stellar explosions represent an opportunity to learn about both stellar and galaxy evolution. Mapping the atomic gas in host galaxies of such transients can lead to an understanding of the conditions triggering them. We provide resolved atomic gas observations of the host galaxy, CGCG137-068, of the unusual, poorly-understood transient AT2018cow searching for clues to understand its nature. We test whether it is consistent with a recent inflow of atomic gas from the intergalactic medium, as suggested for host galaxies of gamma-ray bursts (GRBs) and some supernovae (SNe). We observed the HI hyperfine structure line of the AT2018cow host with the Giant Metrewave Radio Telescope. There is no unusual atomic gas concentration near the position of AT2018cow. The gas distribution is much more regular than those of GRB/SN hosts. The AT2018cow host has an atomic gas mass lower by 0.24dex than predicted from its star formation rate (SFR) and is at the lower edge of the galaxy main sequence. In the continuum we detected the emission of AT2018cow and of a star-forming region in the north-eastern part of the bar (away from AT2018cow). This region hosts a third of the galaxy's SFR. The absence of atomic gas concentration close to AT2018cow, along with a normal SFR and regular HI velocity field, sets CGCG137-068 apart from GRB/SN hosts studied in HI. The environment of AT2018cow therefore suggests that its progenitor may not have been a massive star. Our findings are consistent with an origin of the transient that does not require a connection between its progenitor and gas concentration or inflow: an exploding low-mass star, a tidal disruption event, a merger of white dwarfs, or a merger between a neutron star and a giant star. We interpret the recently reported atomic gas ring in CGCG137-068 as a result of internal processes connected with gravitational resonances caused by the bar.
- ID:
- ivo://CDS.VizieR/J/A+A/449/929
- Title:
- HI observations of Coma Supercluster
- Short Name:
- J/A+A/449/929
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High sensitivity 21-cm HI line observations with an rms noise level of ~0.5mJy were made of 35 spiral galaxies in the Coma Supercluster, using the refurbished Arecibo telescope, leading to detection of 25 objects. These data, combined with the measurements available in the literature, provide the set of HI data for 94% of all late-type galaxies in the Coma Supercluster with an apparent photographic magnitude m_p_<=15.7mag. We confirm that the typical scale of HI deficiency around the Coma cluster is 2Mpc, i.e. one virial radius. Comparing the HI mass function (HIMF) of cluster with non-cluster members of the Coma Supercluster we detected a shortage of high HI mass galaxies among cluster members that can be attributed to the pattern of HI deficiency found in rich clusters.
- ID:
- ivo://CDS.VizieR/J/A+A/365/1
- Title:
- HI observations of LSB galaxies
- Short Name:
- J/A+A/365/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used the Nancay Radio Telescope to obtain new global HI data for 16 giant low surface brightness (LSB) galaxies. Our targets have optical luminosities and disk scale lengths at the high end for spiral galaxies (L_B_~10^10^L_{sun}_ and h_r_>6kpc for H_0_=75km/s/Mpc), but they have diffuse stellar disks, with mean disk surface brightnesses >1 magnitude fainter than normal giant spirals. Thirteen of the galaxies previously had been detected in HI by other workers, but the published HI observations were either confused, resolved by the telescope beam, of low signal-to-noise, or showed significant discrepancies between different authors. For the other 3 galaxies, no HI data were previously available. Several of the galaxies were resolved by the Nancay 3.6' E-W beam, so global parameters were derived from multiple-point mapping observations. Typical HI masses for our sample are >10^10^M_{sun}_, with M_HI_/L_B_=0.3-1.7 (in solar units). All of the observed galaxies have published optical surface photometry, and we have compiled key optical measurements for these objects from the literature. We frequently find significant variations among physical parameters of giant LSB galaxies reported by various workers.
- ID:
- ivo://CDS.VizieR/J/A+A/505/29
- Title:
- HI observations of 2MASS galaxies in ZoA
- Short Name:
- J/A+A/505/29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A pilot survey has been made to obtain 21cm HI emission line profiles for 197 objects in the zone of avoidance (ZoA) that were classified as galaxies in the 2MASS all-sky near-infrared Extended Source Catalog (2MASX), as well as a further 16 2MASS pre-release working database sources that did not make it into 2MASX. One hundred sixteen of the 2MASX sources and the 16 working database sources were observed using the Nancay radio telescope, usually in the 325 to 11825km/s range, and the other 81 2MASX sources were observed with the Arecibo radio telescope in the -500 to 11000km/s range, and for 9 also in the 9500 to 21000km/s range.
- ID:
- ivo://CDS.VizieR/J/A+A/659/A14
- Title:
- HI observations of the MATLAS dwarfs
- Short Name:
- J/A+A/659/A14
- Date:
- 25 Feb 2022 07:33:51
- Publisher:
- CDS
- Description:
- The presence of HI gas in galaxies is inextricably linked to their morphology and evolution. This paper aims to understand the HI content of the already identified 2210 dwarfs located in the low-to-moderate density environments of the MATLAS deep imaging survey. We combine the HI observations from the ATLAS3D survey, with the extragalactic HI sources from the ALFALFA survey, to extract the HI line width, velocity and mass of the MATLAS dwarfs. From the 1773 dwarfs in our sample with available HI observations, 8% (145) have an HI line detection. The majority of the dwarfs show irregular morphology, while 29% (42) are ellipticals, the largest sample of HI-bearing dwarf ellipticals (dEs) to date. Of the HI dwarf sample, 2% (3) are ultra-diffuse galaxies (UDGs), 12% have a transition-type morphology, 5% are tidal dwarf candidates, and 10% appear to be disrupted objects. In our optically selected sample, 9.5% of the dEs, 7% of the UDGs and 10% of the classical dwarfs are HI-bearing. The HI-bearing dwarfs have on average bluer colors than the dwarfs without detected HI. We find relations between the stellar and HI masses, gas fraction, color and absolute magnitude consistent with previous studies of dwarfs probing similar masses and environments. For 79% of the dwarfs identified as satellites of massive early-type galaxies, we find that the HI mass increases with the projected distance to the host. Using the HI line width, we estimate dynamical masses and find that 5% (7) of the dwarfs are dark matter deficient.
