- ID:
- ivo://CDS.VizieR/J/MNRAS/400/1962
- Title:
- Southern GEMS groups. II.
- Short Name:
- J/MNRAS/400/1962
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the neutral hydrogen (HI) content of 16 groups for which we have multiwavelength data including X-ray observations. Wide-field imaging of the groups was obtained with the 20cm multibeam system on the 64m Parkes telescope. We have detected 10 previously uncatalogued HI sources, one of which has no visible optical counterpart. We examine the HI properties of the groups, compared to their X-ray characteristics, finding that those groups with a higher X-ray temperature and luminosity contain less HI per galaxy.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/81/413
- Title:
- Southern sky survey of 1355 spiral galaxies
- Short Name:
- J/ApJS/81/413
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The data from photometric and spectroscopic observations of 1355 southern spiral galaxies are presented and used to determine their distances and peculiar velocities via the Tully-Fisher (TF) relation. I-band CCD surface photometry was carried out using the 1-m and 3.9-m telescopes at Siding Spring Observatory. H-alpha rotation curves for 965 galaxies and 551 H I profiles are presented. The physical parameters, photometric and velocity data, distances, and peculiar velocities of the galaxies are presented in tabular form. The mean distance, systemic velocity, and average peculiar velocity of 24 clusters in the sample are given. TF diagrams are presented for each cluster.
- ID:
- ivo://CDS.VizieR/J/MNRAS/457/2366
- Title:
- Southern ZOA galaxies 21cm HI-line
- Short Name:
- J/MNRAS/457/2366
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-accuracy HI profiles and linewidths are presented for inclined ((b/a)^o^<0.5) spiral galaxies in the southern Zone of Avoidance (ZOA). These galaxies define a sample for use in the determinations of peculiar velocities using the near-infrared Tully-Fisher (TF) relation. The sample is based on the 394 HI-selected galaxies from the Parkes HI Zone of Avoidance survey (HIZOA). Follow-up narrow-band Parkes HI observations were obtained in 2010 and 2015 for 290 galaxies, while for the further 104 galaxies, sufficiently high signal-to-noise (S/N) spectra were available from the original HIZOA data. All 394 spectra are reduced and parametrized in the same systematic way. Five different types of linewidth measurements were derived, and a Bayesian mixture model was used to derive conversion equations between these five widths. Of the selected and measure galaxies, 342 have adequate signal to noise (S/N>=5) for use in TF distance estimation. The average value of the S/N ratio of the sample is 14.7. We present the HI parameters for these galaxies. The sample will allow a more accurate determination of the flow field in the southern ZOA which bisects dynamically important large-scale structures such as Puppis, the Great Attractor, and the Local Void.
- ID:
- ivo://CDS.VizieR/J/A+A/416/515
- Title:
- Starbursts in barred spiral galaxies. VI.
- Short Name:
- J/A+A/416/515
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper reports a study of the effect of a bar on the neutral hydrogen (HI) content of starburst and Seyfert galaxies. We also make comparisons with a sample of "normal" galaxies and investigate how well starburst and Seyfert galaxies follow the fundamental scaling Tully-Fisher (TF) relation defined for normal galaxies. 111 Markarian (Mrk) IRAS galaxies were observed with the Nancay radiotelescope, and HI data were obtained for 80 galaxies, of which 64 are new detections. We determined the (20 and 50%) linewidths, the maximum velocity of rotation and total HI flux for each galaxy. These measurements are complemented by data from the literature to form a sample of Mrk IRAS (74% starburst, 23% Seyfert and 3% unknown) galaxies containing 105 unbarred and 113 barred ones. Barred galaxies have lower total and bias-corrected HI masses than unbarred galaxies, and this is true for both Mrk IRAS and normal galaxies. This robust result suggests that bars funnel the HI gas toward the center of the galaxy where it becomes molecular before forming new stars. The Mrk IRAS galaxies have higher bias-corrected HI masses than normal galaxies. They also show significant departures from the TF relation, both in the B and K bands. The most deviant points from the TF relation tend to have a strong far-infrared luminosity and a low oxygen abundance. These results suggest that a fraction of our Mrk IRAS galaxies are still in the process of formation, and that their neutral HI gas, partly of external origin, has not yet reached a stationary state.
- ID:
- ivo://CDS.VizieR/J/AJ/136/2782
- Title:
- Star formation efficiency in nearby galaxies
- Short Name:
- J/AJ/136/2782
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We measure the star formation efficiency (SFE), the star formation rate (SFR) per unit of gas, in 23 nearby galaxies and compare it with expectations from proposed star formation laws and thresholds. We use HI maps from The HI Nearby Galaxy Survey (THINGS) and derive H_2_ maps of CO measured by HERA CO-Line Extragalactic Survey and Berkeley-Illinois-Maryland Association Survey of Nearby Galaxies. We estimate the SFR by combining Galaxy Evolution Explorer (GALEX) far-ultraviolet maps and the Spitzer Infrared Nearby Galaxies Survey (SINGS) 24um maps, infer stellar surface density profiles from SINGS 3.6um data, and use kinematics from THINGS.
- ID:
- ivo://CDS.VizieR/J/ApJ/708/841
- Title:
- Star formation in E/S0 galaxies
- Short Name:
- J/ApJ/708/841
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recent work has identified a population of low-redshift E/S0 galaxies that lie on the blue sequence in color versus stellar mass parameter space, where spiral galaxies typically reside. While high-mass blue-sequence E/S0s often resemble young merger or interaction remnants likely to fade to the red sequence, we focus on blue-sequence E/S0s with lower stellar masses (M_*_<a fewx10^10^M_{sun}_), which are characterized by fairly regular morphologies and low-density field environments where fresh gas infall is possible. This population may provide an evolutionary link between early-type galaxies and spirals through disk regrowth. Focusing on atomic gas reservoirs, we present new GBT HI data for 27 E/S0s on both sequences as well as a complete tabulation of archival HI data for other galaxies in the Nearby Field Galaxy Survey. Normalized to stellar mass, the atomic gas masses for 12 of the 14 blue-sequence E/S0s range from 0.1 to >1.0, demonstrating that morphological transformation is possible if the detected gas can be converted into stars. These gas-to-stellar mass ratios are comparable to those of spiral and irregular galaxies and have a similar dependence on stellar mass.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/68.243
- Title:
- Star formation in isolated galaxies
- Short Name:
- J/other/AstBu/68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use the FUV fluxes measured with the GALEX to study the star formation properties of galaxies collected in the Local Orphan Galaxies catalog (LOG, 2011AstBu..66....1K). Among 517 LOG galaxies having radial velocities V_LG_<3500km/s and Galactic latitudes |b|>15{deg}, 428 objects have been detected in FUV. We briefly discuss some scaling relations between the specific star formation rate (SSFR) and stellar mass, HI-mass, morphology, and surface brightness of galaxies situated in extremely low density regions of the Local Supercluster. Our sample is populated with predominantly late-type, gas-rich objects with the median morphological type of Sdm. Only 5% of LOG galaxies are classified as early types: E, S0, S0/a, however, they systematically differ from normal E and S0 galaxies by lower luminosity and presence of gas and dust. We find that almost all galaxies in our sample have their SSFR below 0.4Gyr^-1^. This limit is also true even for a sample of 260 active star-burst Markarian galaxies situated in the same volume. The existence of such a quasi-Eddington limit for galaxies seems to be a key factor which characterizes the transformation of gas into stars at the current epoch.
- ID:
- ivo://CDS.VizieR/J/AJ/130/2613
- Title:
- The Arecibo Legacy Fast ALFA survey. II
- Short Name:
- J/AJ/130/2613
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In preparation for the full Arecibo Legacy Fast ALFA (ALFALFA) extragalactic HI survey, precursor observations were carried out in 2004 August-September with the seven-beam Arecibo L-band Feed Array (ALFA) receiver system and the Wideband Arecibo Pulsar Processor spectral processors. While these observations were geared mainly at testing and debugging survey strategy, hardware, and software, approximately 48hr of telescope time yielded science-quality data. To test our ability to discriminate cosmic signals from radio-frequency interference and noise, 165 candidates ranging in reliability likelihood were reobserved with the single-beam L-band wide system at Arecibo in 2005 January-February. Of those, 41% were confirmed as real. We present the results of both the ALFA and the single-beam observations for the sample of 166 confirmed HI sources, as well as our assessment of their optical counterparts.
- ID:
- ivo://CDS.VizieR/J/AJ/157/81
- Title:
- The Arecibo PPS Survey. I. Harvesting ALFALFA
- Short Name:
- J/AJ/157/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a multi-objective campaign of targeted 21 cm H I line observations of sources selected from the Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) survey and galaxies identified by their morphological and photometric properties in the Sloan Digital Sky Survey. The aims of this program have been (1) to confirm the reality of some ALFALFA sources whose enigmatic nature suggest additional multiwavelength observations; (2) to probe the low signal-to-noise ratio (S/N) regime, below the ALFALFA reliability limit; and (3) to explore the feasibility of using optical morphology, color, and surface brightness to identify gas-rich objects in the region of the Pisces-Perseus Supercluster (PPS) whose H I fluxes are below the ALFALFA sensitivity limit at that distance. As expected, the reliability of ALFALFA detections depends strongly on the S/N of the H I line signal and its coincidence with a probable stellar counterpart identified by its optical properties, suggestive of ongoing star formation. The identification of low-mass, star-forming populations enables targeted H I line observations to detect galaxies with H I line fluxes below the ALFALFA sensitivity limits in fixed local volumes (D<100 Mpc). The method explored here serves as the basis for extending the sample of gas-bearing objects as part of the ongoing Arecibo Pisces-Perseus Supercluster Survey (APPSS).
- ID:
- ivo://CDS.VizieR/J/ApJ/872/81
- Title:
- The COS CGM Compendium (CCC). II. Lyman limit syst.
- Short Name:
- J/ApJ/872/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results from our COS circumgalactic medium (CGM) compendium (CCC), a survey of the CGM at z<~1 using HI-selected absorbers with 15<logN_HI_<19. We focus here on 82 partial Lyman limit systems (pLLSs, 16.2<=logN_HI_<17.2) and 29 LLSs (17.2<=logN_HI_<19). Using Bayesian techniques and Markov Chain Monte Carlo sampling of a grid of photoionization models, we derive the posterior probability distribution functions (PDFs) for the metallicity of each absorber in CCC. We show that the combined pLLS metallicity PDF at z<~1 has two main peaks at [X/H]~-1.7 and -0.4, with a strong dip at [X/H]~-1. The metallicity PDF of the LLSs might be more complicated than a unimodal or bimodal distribution. The pLLSs and LLSs probe a similar range of metallicities -3<~[X/H]<~+0.4, but the fraction of very metal-poor absorbers with [X/H]<~-1.4 is much larger for the pLLSs than the LLSs. In contrast, absorbers with logN_HI_>=19 have mostly -1<~[X/H]<~0 at z<~1. The metal-enriched gas probed by pLLSs and LLSs confirms that galaxies that have been enriching their CGM over billions of years. Surprisingly, despite this enrichment, there is also abundant metal-poor CGM gas (41%-59% of the pLLSs have [X/H]<~-1.4), representing a reservoir of near-pristine gas around z<~1 galaxies. We compare our empirical results to recent cosmological zoom simulations, finding some discrepancies, including an overabundance of metal- enriched CGM gas in simulations.
