- ID:
- ivo://CDS.VizieR/J/A+A/558/A18
- Title:
- HI spectra of extremely metal-poor (XMP) galaxies
- Short Name:
- J/A+A/558/A18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Extremely metal-poor (XMP) galaxies are chemically, and possibly dynamically, primordial objects in the local Universe. Our objective is to characterize the HI content of the XMP galaxies as a class, using as a reference the list of 140 known local XMPs compiled by Morales-Luis et al. (2011, Cat. J/ApJ/743/77). We have observed 29 XMPs, which had not been observed before at 21 cm, using the Effelsberg radio telescope. This information was complemented with Hi data published in literature for a further 53 XMPs. In addition, optical data from the literature provided morphologies, stellar masses, star-formation rates and metallicities.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/566/A71
- Title:
- HI study of 18 nearby dwarf galaxies
- Short Name:
- J/A+A/566/A71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the dynamics of starbursting dwarf galaxies, using both new and archival HI observations. We consider 18 nearby galaxies that have been resolved into single stars by HST observations, providing their star-formation history and total stellar mass. We find that 9 objects have a regularly rotating HI disk, 7 have a kinematically disturbed HI disk, and 2 show unsettled HI distributions. Two galaxies (NGC 5253 and UGC 6456) show a velocity gradient along the minor axis of the HI disk, which we interpret as strong radial motions. For galaxies with a regularly rotating disk we derive rotation curves, while for galaxies with a kinematically disturbed disk we estimate the rotation velocities in their outer parts. We derive baryonic fractions within about 3 optical scale lengths and find that, on average, baryons constitute at least 30% of the total mass. Despite the star formation having injected 10^56^ergs in the ISM in the past 500 Myr, these starbursting dwarfs have both baryonic and gas fractions similar to those of typical dwarf irregulars, suggesting that they did not eject a large amount of gas out of their potential wells.
- ID:
- ivo://CDS.VizieR/J/A+A/564/A116
- Title:
- HI supershells catalogue
- Short Name:
- J/A+A/564/A116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The HI supershells catalogue was carried out making use of the Leiden-Argentine-Bonn (LAB) HI survey in the outer part of the Galaxy. The identification of the supershell candidates was made using a combination of two techniques: a visual inspection one plus an automatic searching algorithm. A total of 566 supershell candidates were identified. Most of them (347) are located in the second galactic quadrant, while 219 were found in the third one.
164. 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.
- ID:
- ivo://CDS.VizieR/J/A+A/319/401
- Title:
- HI survey of polar ring galaxies. II.
- Short Name:
- J/A+A/319/401
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a neutral hydrogen survey conducted with the 100-m radiotelescope at Effelsberg of 44 northern objects in the polar-ring galaxy atlas of Whitmore et al. (1990AJ....100.1489W). These observations were performed to complement the Green Bank observations of polar-ring galaxies (Paper I, 1994AJ....107...99R). We detected 29 of these above our detection limit of a few mJy. The relative content of neutral hydrogen (M_HI_/L_B_) of the early-type galaxies (E, S0) in this sample is significantly higher than for galaxies of the same morphological types from comparison samples, i.e. for elliptical galaxies M_HI_/L_B_=0.17+/-0.09 and for S0 galaxies M_HI_/L_B_=0.75+/-0.13 which is about 6 times the mean value from the comparison samples for the same morphological types.
- 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.
- 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).
- ID:
- ivo://CDS.VizieR/VIII/75
- Title:
- HI survey of the sky DE<+25{deg}
- Short Name:
- VIII/75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the final data release of the high sensitivity {lambda}21-cm neutral hydrogen survey of the sky south of {delta}<=-25{deg}. A total of 50980 positions lying on a galactic coordinate grid with points spaced by ({Delta}l, {Delta}b)=(0.5{deg}/cosb, 0.5{deg}) were observed with the 30m dish of the Instituto Argentino de Radioastronomica (IAR). The angular resolution of the survey is HPBW=0.5{deg} and the velocity coverage spans the interval -450km/s to +400km/s (LSR). The velocity resolution is 1.27km/s and the final rms noise of the entire database is 0.07K. The data are corrected for stray radiation and converted to brightness temperatures.
- ID:
- ivo://CDS.VizieR/J/A+A/370/765
- Title:
- HI synthesis observations in UMa cluster
- Short Name:
- J/A+A/370/765
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this data paper we present the results of an extensive 21 cm-line synthesis imaging survey of 43 spiral galaxies in the nearby Ursa Major cluster using the Westerbork Synthesis Radio Telescope. Detailed kinematic information in the form of position-velocity diagrams and rotation curves is presented in an atlas together with HI channel maps, 21 cm continuum maps, global HI profiles, radial HI surface density profiles, integrated HI column density maps, and HI velocity fields. The relation between the corrected global HI linewidth and the rotational velocities Vmax and Vflat as derived from the rotation curves is investigated. Inclination angles obtained from the optical axis ratios are compared to those derived from the inclined HI disks and the HI velocity fields. The galaxies were not selected on the basis of their HI content but solely on the basis of their cluster membership and inclination which should be suitable for a kinematic analysis. The observed galaxies provide a well-defined, volume limited and equidistant sample, useful to investigate in detail the statistical properties of the Tully-Fisher relation and the dark matter halos around them.
- ID:
- ivo://CDS.VizieR/J/MNRAS/476/3744
- Title:
- HIX galaxy survey. II.
- Short Name:
- J/MNRAS/476/3744
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- By analysing a sample of galaxies selected from the HI Parkes All Sky Survey (HIPASS) to contain more than 2.5 times their expected HI content based on their optical properties, we investigate what drives these HI eXtreme (HIX) galaxies to be so HI-rich. We model the HI kinematics with the Tilted Ring Fitting Code TiRiFiC and compare the observed HIX galaxies to a control sample of galaxies from HIPASS as well as simulated galaxies built with the semi-analytic model DARK SAGE. We find that (1) HI discs in HIX galaxies are more likely to be warped and more likely to host HI arms and tails than in the control galaxies, (2) the average HI and average stellar column density of HIX galaxies is comparable to the control sample, (3) HIX galaxies have higher HI and baryonic specific angular momenta than control galaxies, (4) most HIX galaxies live in higher spin haloes than most control galaxies. These results suggest that HIX galaxies are HI-rich because they can support more HI against gravitational instability due to their high specific angular momentum. The majority of the HIX galaxies inherits their high specific angular momentum from their halo. The HI content of HIX galaxies might be further increased by gas-rich minor mergers. This paper is based on data obtained with the Australia Telescope Compact Array through the large program C2705.
