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731. HIJASS HI survey in the Ursa Major region
ID:
ivo://CDS.VizieR/J/MNRAS/428/1790
Title:
HIJASS HI survey in the Ursa Major region
Short Name:
J/MNRAS/428/1790
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have conducted the first blind HI survey covering 480deg^2^ and a heliocentric velocity range from 300 to 1900km/s to investigate the HI content of the nearby spiral-rich Ursa Major region and to look for previously uncatalogued gas-rich objects. Here we present the catalogue of HI sources. The HI data were obtained with the four-beam receiver mounted on the 76.2-m Lovell telescope [full width at half-maximum (FWHM) 12-arcmin] at the Jodrell Bank Observatory (UK) as part of the HI Jodrell All Sky Survey (HIJASS). We use the automated source finder DUCHAMP and identify 166 HI sources in the data cubes with HI masses in the range of 107-1010.5M_{sun}_. Our Ursa Major HI catalogue includes 10 first-time detections in the 21-cm emission line. We identify optical counterparts for 165 HI sources (99%). For 54 HI sources (~33%) we find numerous optical counterparts in the HIJASS beam, indicating a high density of galaxies and likely tidal interactions. Four of these HI systems are discussed in detail. We find only one HI source (1%) without a visible optical counterpart out of the 166 HI detections. Green Bank Telescope (FWHM 9-arcmin) follow-up observations confirmed this HI source and its HI properties. The nature of this detection is discussed and compared to similar sources in other HI surveys.
732. HI lines in 586 galaxies
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/
733. HI Nearby Galaxy Survey, THINGS
ID:
ivo://CDS.VizieR/J/AJ/136/2563
Title:
HI Nearby Galaxy Survey, THINGS
Short Name:
J/AJ/136/2563
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present "The HI Nearby Galaxy Survey (THINGS)," a high spectral (<=5.2km/s) and spatial (~6") resolution survey of HI emission in 34 nearby galaxies obtained using the NRAO Very Large Array (VLA). The overarching scientific goal of THINGS is to investigate fundamental characteristics of the interstellar medium (ISM) related to galaxy morphology, star formation, and mass distribution across the Hubble sequence. Unique characteristics of the THINGS database are the homogeneous sensitivity as well as spatial and velocity resolution of the HI data, which is at the limit of what can be achieved with the VLA for a significant number of galaxies. A sample of 34 objects at distances 2<~D>~15Mpc (resulting in linear resolutions of ~100 to 500pc) are targeted in THINGS, covering a wide range of star formation rates (~10^-3^ to 6M_{sun}_/yr), total HI masses MHI (0.01 to 14x10^9^M_{sun}_), absolute luminosities MB (-11.5 to -21.7mag), and metallicities (7.5 to 9.2 in units of 12+log[O/H]). We describe the setup of the VLA observations, the data reduction procedures, and the creation of the final THINGS data products. We present an atlas of the integrated HI maps, the velocity fields, the second moment (velocity dispersion) maps and individual channel maps of each THINGS galaxy. The THINGS data products are made publicly available through a dedicated webpage (http://www.mpia.de/THINGS). Accompanying THINGS papers (in this issue of the Astronomical Journal) address issues such as the small-scale structure of the ISM, the (dark) matter distribution in THINGS galaxies, and the processes leading to star formation.
734. HI observations of AT 2018cow
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.
735. HI observations of 2MASS galaxies in ZoA
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.
736. HIPASS in Fornax
ID:
ivo://CDS.VizieR/J/MNRAS/337/641
Title:
HIPASS in Fornax
Short Name:
J/MNRAS/337/641
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using data from the HI Parkes All Sky Survey (HIPASS), we have searched for neutral hydrogen in galaxies in a region <25x25{deg}^2^ centred on NGC 1399, the nominal centre of the Fornax cluster. Within a velocity search range of 300-3700km/s and to a 3 lower flux limit of ~40mJy, 110 galaxies with HI emission were detected, one of which is previously uncatalogued. None of the detections has early-type morphology. Previously unknown velocities for 14 galaxies have been determined, with a further four velocity measurements being significantly dissimilar to published values. Identification of an optical counterpart is relatively unambiguous for more than ~90 per cent of our HI galaxies. The galaxies appear to be embedded in a sheet at the cluster velocity which extends for more than 30across the search area. At the nominal cluster distance of ~20Mpc, this corresponds to an elongated structure more than 10Mpc in extent. A velocity gradient across the structure is detected, with radial velocities increasing by ~500km/s from south-east to north-west. The clustering of galaxies evident in optical surveys is only weakly suggested in the spatial distribution of our HI detections. Of 62 HI detections within a 10{deg} projected radius of the cluster centre, only two are within the core region (projected radius <1{deg}) and less than 30 per cent are within 3.5{deg}, suggesting a considerable deficit of HI-rich galaxies in the centre of the cluster. However, relative to the field, there is a 3(+/-1)-fold excess of HI-rich galaxies in the outer parts of the cluster where galaxies may be infalling towards the cluster for the first time.
737. HIPASS-ZoA HII regions
ID:
ivo://CDS.VizieR/J/MNRAS/450/2025
Title:
HIPASS-ZoA HII regions
Short Name:
J/MNRAS/450/2025
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a Radio Recombination Line (RRL) survey of the Galactic plane from the Hi Parkes All-sky Survey and associated Zone of Avoidance survey, which mapped the region l=196{deg}-0{deg}-52{deg} and |b|<=5{deg} at 1.4GHz and 14.4-arcmin resolution. We combine three RRLs, H168{alpha}, H167{alpha}, and H166{alpha} to derive fully sampled maps of the diffuse ionized emission along the inner Galactic plane. The velocity information, at a resolution of 20km/s, allows us to study the spatial distribution of the ionized gas and compare it with that of the molecular gas, as traced by CO. The longitude-velocity diagram shows that the RRL emission is mostly associated with CO gas from the molecular ring and is concentrated within the inner 30{deg} of longitude. A map of the free-free emission in this region of the Galaxy is derived from the line-integrated RRL emission, assuming an electron temperature gradient with Galactocentric radius of 496+/-100K/kpc. Based on the thermal continuum map, we extracted a catalogue of 317 compact (<~15-arcmin) sources, with flux densities, sizes, and velocities. We report the first RRL observations of the southern ionized lobe in the Galactic Centre. The line profiles and velocities suggest that this degree-scale structure is in rotation. We also present new evidence of diffuse ionized gas in the 3-kpc arm. Helium and carbon RRLs are detected in this survey. The He line is mostly observed towards HII regions, whereas the C line is also detected further away from the source of ionization. These data represent the first observations of diffuse C RRLs in the Galactic plane at a frequency of 1.4GHz.
738. HI survey of AGNs
ID:
ivo://CDS.VizieR/J/ApJS/177/103
Title:
HI survey of AGNs
Short Name:
J/ApJS/177/103
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have conducted a new Arecibo survey for HI emission for 113 galaxies with broad-line (type 1) active galactic nuclei (AGNs) out to recession velocities as high as ~35000km/s. The primary aim of the study is to obtain sensitive HI spectra for a well-defined, uniformly selected sample of active galaxies that have estimates of their black hole masses in order to investigate correlations between HI properties and the characteristics of the AGNs. HI emission was detected in 66 out of the 101 (65%) objects with spectra uncorrupted by radio frequency interference, among which 45 (68%) have line profiles with adequate signal-to-noise ratio and sufficiently reliable inclination corrections to yield robust deprojected rotational velocities. This paper presents the basic survey products, including an atlas of HI spectra, measurements of HI flux, line width, profile asymmetry, optical images, optical spectroscopic parameters, as well as a summary of a number of derived properties pertaining to the host galaxies. To enlarge our primary sample, we also assemble all previously published HI measurements of type 1 AGNs for which we can estimate black hole masses, which total an additional 53 objects. The final comprehensive compilation of 154 broad-line active galaxies, by far the largest sample ever studied, forms the basis of our companion paper, which uses the HI database to explore a number of properties of the AGN host galaxies.
739. HI survey of polar ring galaxies. IV.
ID:
ivo://CDS.VizieR/J/A+A/386/140
Title:
HI survey of polar ring galaxies. IV.
Short Name:
J/A+A/386/140
Date:
21 Oct 2021
Publisher:
CDS
Description:
A total of 33 polar ring galaxies and polar ring galaxy candidates were observed in the 21-cm HI line with the 64-m Parkes radio telescope. The objects, selected by their optical morphology, are all south of declination -39{deg} and in only 5 of them had been reported previously. HI line emission was detected towards 18 objects, though in 3 cases the detection may be confused by another galaxy in the telescope beam, and one is a marginal detection. Eight objects were detected for the first time in HI, of which 5 did not have previously known redshifts.
740. H I Survey of the Galactic Center Region
ID:
ivo://CDS.VizieR/J/A+AS/52/63
Title:
H I Survey of the Galactic Center Region
Short Name:
J/A+AS/52/63
Date:
21 Oct 2021
Publisher:
CDS
Description:
Presented here are 21-cm (1.42GHz) observations of neutral hydrogen emission from the core of our Galaxy made over a period of several years with the 140-foot telescope of the National Radio Astronomy Observatory. The survey covers the region 348 < l < 10, -10 < b < 10 with an angular resolution of 21' and a grid spacing of 0.5 degrees in both l and b, and the velocity range |v| < 310 km/s with a kinematic resolution of 5.5 km/s. The sensitivity of the data generally corresponds to an antenna-temperature rms level of 0.02 K or better. The H I spectra from the survey are archived in a single three-dimensional (v, l, b) data cube in FITS image format. There are 224 velocity channels with a step of 2.75 km/s between channels. The intensities are given in units of antenna temperature and can be converted to brightness temperature units by multiplying by a factor of (1.52).