- ID:
- ivo://CDS.VizieR/J/A+A/113/61
- Title:
- HI data for 392 spiral galaxies
- Short Name:
- J/A+A/113/61
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 392 spiral galaxies with type Sb or later have been detected in the 21-cm line of neutral hydrogen with the Nancay radiotelescope, and among them 172 HI fluxes are obtained for the first time. The source of any possible bias has been carefully analyzed and only the Malmquist bias appears to be significant. In order to obviate this observational effect, the range of radial velocities has been properly truncated for all statistical studies. A mean value of each global parameter has been determined for each morphological type and compared to previous results.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/434/887
- Title:
- HI data of blue compact dwarf galaxies
- Short Name:
- J/A+A/434/887
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present HI-observations of 56 blue compact dwarf (BCD) galaxies of which 44 have been detected in the 21-cm line from neutral hydrogen with the 100-m radiotelescope at Effelsberg. Optical data (e.g., from NED) and HI data from other observers and telescopes are used to estimate the likelihood of confusion from other galaxies within the Effelsberg beam. The selected 29 BCD galaxies without any sign of confusion are used to infer several characteristic properties of the BCD galaxy population. In some respects, they resemble normal galaxies: e.g., the relations between global parameters like linear diameter A0 versus blue luminosity LB and the M_HI_/LB ratio vs. LB. At least five of these BCDGs emit milli-Jansky level radio continuum emission.
- ID:
- ivo://CDS.VizieR/J/A+A/435/459
- Title:
- HI data of edge-on spiral galaxies
- Short Name:
- J/A+A/435/459
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Neutral hydrogen observations with the 100-m Effelsberg radio telescope are presented for 268 spiral galaxies from the Revised Flat Galaxy Catalog (<VII/219>). Fluxes, radial velocities and line widths are given for 121 detected galaxies, as well as search parameters for 147 undetected objects. Most of the detected galaxies are late type (Sbc -- Sdm) spirals with a mean M_25_/L_B ratio of 2.5 in solar units. (M_25_ is the total mass within the 25mag/arcsec^2^ isophote) and a mean hydrogen mass fraction M_HI_/M_25_=0.13. Correlations between global parameters are discussed briefly. A comparison with a sample of nearby galaxies (within 10Mpc) demonstrates the validity of the same linear relation between the optical luminosity (L_B_) and the linear diameter (A_25_) down to the smallest galaxies.
- ID:
- ivo://CDS.VizieR/J/A+AS/126/471
- Title:
- HI data of galaxies from Kazarian's lists
- Short Name:
- J/A+AS/126/471
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The 21-cm neutral hydrogen line has been measured for the first time in 39 non-Seyfert type galaxies from Kazarian list, with the Nancay radiotelescope. The line profiles, widths at 20% and 50% of the peak intensity, radial velocities as well as total fluxes are presented. The values of radial velocity are in fairly good agreement with those obtained from optical spectra. The width values at 20% of the peak vary in wide range from 113km/s (KAZ 579) to 608km/s for KAZ 566. Nine of our objects remained undetected, whether their HI-flux was too faint, the integration time too short, or the frequency sighted wrong. However, for part of them, there were positive hint of detection. Comments on individual objects are given.
- ID:
- ivo://CDS.VizieR/J/MNRAS/307/236
- Title:
- HI data of Puppis galaxies
- Short Name:
- J/MNRAS/307/236
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report 21-cm H I line observations of 161 galaxies located behind the Milky Way, in the Puppis region. The observations have been carried out with the Nancay radio telescope, resulting in 101 detections. Most of the galaxies observed appear in the ESO catalogue, and present apparent diameters larger than 1.6arcmin. We show that the detection rate is strongly related to the apparent diameter; it is as high as 76 per cent for diameters larger than 1.6arcmin. Half of the non-detections result, in fact, from an insufficient velocity coverage. Global parameters of the detected galaxies are computed, after a careful discussion of the correction for Galactic absorption.
116. HIDEEP survey
- ID:
- ivo://CDS.VizieR/J/MNRAS/346/787
- Title:
- HIDEEP survey
- Short Name:
- J/MNRAS/346/787
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have carried out an extremely long integration time (9000s/beam) 21-cm blind survey of 60deg^2^ in Centaurus using the Parkes multibeam system. We find that the noise continues to fall as sqrt(t_obs_) throughout, enabling us to reach an H I column-density limit of 4.2x10^18^cm^-2^ for galaxies with a velocity width of 200km/s in the central 32deg^2^ region, making this the deepest survey to date in terms of column density sensitivity. The H I data are complemented by very deep optical observations from digital stacking of multi-exposure UK Schmidt Telescope R-band films, which reach an isophotal level of 26.5Rmag/arcsec^2^ (27.5Bmag/arcsec^2^). 173 H I sources have been found, 96 of which have been uniquely identified with optical counterparts in the overlap area.
- ID:
- ivo://CDS.VizieR/J/A+A/659/A94
- Title:
- HI-detected Coma and field galaxies properties
- Short Name:
- J/A+A/659/A94
- Date:
- 14 Mar 2022 06:46:08
- Publisher:
- CDS
- Description:
- We present the blind Westerbork Coma Survey probing the HI content of the Coma galaxy cluster with the Westerbork Synthesis Radio Telescope. The survey covers the inner ~1Mpc around the cluster centre, extending out to 1.5Mpc towards the south-western NGC 4839 group. The survey probes the atomic gas in the entire Coma volume down to a sensitivity of ~10^19^cm^-2^ and 10^8^M_{sun}_. Combining automated source finding with source extraction at optical redshifts and visual verification, we obtained 40 HI detections of which 24 are new. Over half of the sample displays perturbed HI morphologies indicative of an ongoing interaction with the cluster environment. With the use of ancillary UV and mid-IR, data we measured their stellar masses and star formation rates and compared the HI properties to a set of field galaxies spanning a similar stellar mass and star formation rate range. We find that ~75% of HI-selected Coma galaxies have simultaneously enhanced star formation rates (by ~0.2dex) and are HI deficient (by ~0.5dex) compared to field galaxies of the same stellar mass. According to our toy model, the simultaneous HI deficiency and enhanced star formation activity can be attributed to either HI stripping of already highly star forming galaxies on a very short timescale, while their H_2_ content remains largely unaffected, or to HI stripping coupled to a temporary boost of the HI-to-H_2_ conversion, causing a brief starburst phase triggered by ram pressure before eventually quenching the galaxy.
- ID:
- ivo://CDS.VizieR/J/AJ/128/2080
- Title:
- HI emission observations
- Short Name:
- J/AJ/128/2080
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have taken advantage of the improved baselines and higher sensitivity available with the upgraded Arecibo 305m telescope to create a new HI spectral line catalog of disk galaxies that can be used as a reference catalog for anyone interested in 21cm spectral line work. In all, 108 galaxies were observed, covering 24hr of the sky at declinations between 0{deg} and 36{deg} and velocities between 0 and 25,000km/s. The majority of the galaxies were observed at least two times on different nights to avoid problems with radio frequency interference, baseline fluctuations, etc. Comparing our measured values with all those available in the literature shows that although large individual variations may exist, the average difference between the measurements is zero. In all we have considerable confidence in our measurements, and the resulting catalog should be extremely useful as a well-defined reference catalog for anyone interested in 21cm spectral line work.
- ID:
- ivo://CDS.VizieR/J/MNRAS/437/2017
- Title:
- HI-galaxy cross-correlation at z<~1
- Short Name:
- J/MNRAS/437/2017
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new optical spectroscopic survey of 1777 'star-forming' ('SF') and 366 'non-star-forming' ('non-SF') galaxies at redshifts z~0-1 (2143 in total), 22 AGN and 423 stars, observed by instruments such as the Deep Imaging Multi-Object Spectrograph, the Visible Multi-Object Spectrograph and the Gemini Multi-Object Spectrograph, in three fields containing five quasi-stellar objects (QSOs) with Hubble Space Telescope (HST) ultraviolet spectroscopy. We also present a new spectroscopic survey of 173 'strong' (10^14^<=N_HI_<~10^17^cm^-2^) and 496 'weak' (10^13^<~N_HI_<10^14^cm^-2^) intervening HI (Ly{alpha}) absorption-line systems at z<~1 (669 in total), observed in the spectra of eight QSOs at z~1 by the Cosmic Origins Spectrograph and the Faint Object Spectrograph on the HST. Combining these new data with previously published galaxy catalogues such as the Very Large Telescope Visible Multi-Object Spectrograph Deep Survey and the Gemini Deep Deep Survey, we have gathered a sample of 654 HI absorption systems and 17509 galaxies at transverse scales <~50Mpc, suitable for a two-point correlation function analysis. We present observational results on the HI-galaxy ({xi}_ag_) and galaxy-galaxy ({xi}_gg_) correlations at transverse scales r_perp_<~10Mpc, and the HI-HI autocorrelation ({xi}_aa_) at transverse scales r_perp_<~2Mpc.
- ID:
- ivo://CDS.VizieR/J/MNRAS/464/3796
- Title:
- HI gas mass fraction estimations
- Short Name:
- J/MNRAS/464/3796
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The application of artificial neural networks (ANNs) for the estimation of HI gas mass fraction (M_HI_/M*) is investigated, based on a sample of 13 674 galaxies in the Sloan Digital Sky Survey (SDSS) with HI detections or upper limits from the Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA). We show that, for an example set of fixed input parameters (g-r colour and i-band surface brightness), a multidimensional quadratic model yields M_HI_/M* scaling relations with a smaller scatter (0.22dex) than traditional linear fits (0.32dex), demonstrating that non-linear methods can lead to an improved performance over traditional approaches. A more extensive ANN analysis is performed using 15 galaxy parameters that capture variation in stellar mass, internal structure, environment and star formation. Of the 15 parameters investigated, we find that g-r colour, followed by stellar mass surface density, bulge fraction and specific star formation rate have the best connection with M_HI_/M*. By combining two control parameters, that indicate how well a given galaxy in SDSS is represented by the ALFALFA training set (PR) and the scatter in the training procedure ({sigma}_fit_), we develop a strategy for quantifying which SDSS galaxies our ANN can be adequately applied to, and the associated errors in the M_HI_/M* estimation. In contrast to previous works, our M_HI_/M* estimation has no systematic trend with galactic parameters such as M*, g-r and star formation rate. We present a catalogue of M_HI_/M* estimates for more than half a million galaxies in the SDSS, of which ~150000 galaxies have a secure selection parameter with average scatter in the M_HI_/M* estimation of 0.22dex.
