- ID:
- ivo://CDS.VizieR/J/MNRAS/437/1070
- Title:
- DYNAMO. H{alpha} luminous galaxies sample
- Short Name:
- J/MNRAS/437/1070
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- DYNAMO is a multiwavelength, spatially resolved survey of local (z~0.1) star-forming galaxies designed to study evolution through comparison with samples at z=~2. Half of the sample has integrated H{alpha luminosities of >10^42^erg/s, the typical lower limit for resolved spectroscopy at z=~2. The sample covers a range in stellar mass (10^9^-10^11^M_{sun_) and star formation rate (0.2-100M_{sun}_/yr). In this first paper of a series, we present integral-field spectroscopy of H{alpha emission for the sample of 67 galaxies. We infer gas fractions in our sample as high as =~0.8, higher than typical for local galaxies. Gas fraction correlates with stellar mass in galaxies with star formation rates below 10M_{sun}_/yr, as found by COLDGASS, but galaxies with higher star formation rates have higher than expected gas fractions. There is only a weak correlation, if any, between gas fraction and gas velocity dispersion. Galaxies in the sample visually classified as disc-like are offset from the local stellar mass Tully-Fisher relation to higher circular velocities, but this offset vanishes when both gas and stars are included in the baryonic Tully-Fisher relation. The mean gas velocity dispersion of the sample is =~50km/s, and V/{sigma} ranges from 2 to 10 for most of the discs, similar to 'turbulent' galaxies at high redshift. Half of our sample show disc-like rotation, while ~20 percent show no signs of rotation. The division between rotating and non-rotating is approximately equal for the sub-samples with either star formation rates >10M_{sun}_/yr, or specific star formation rates typical of the star formation 'main sequence' at z=~2. Across our whole sample, we find good correlation between the dominance of `turbulence' in galaxy discs (as expressed by V/{sigma}) and gas fraction as has been predicted for marginally stable Toomre discs. Comparing our sample with many others at low- and high-redshift reveals a correlation between gas velocity dispersion and star formation rate. These findings suggest the DYNAMO discs are excellent candidates for local galaxies similar to turbulent z=~2 disc galaxies.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/390/383
- Title:
- E+A and companion galaxies
- Short Name:
- J/MNRAS/390/383
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on our intensive spectroscopic campaign with the GoldCam spectrograph on the Kitt Peak National Observatory (KPNO) 2.1-m telescope, we have constructed the first catalogue of E+A galaxies with spectroscopic companion galaxies, and investigated a probability that an E+A galaxy has close companion galaxies. We selected 660 E+A galaxies with 4.0{AA}<H{delta} EW at a redshift of <0.167 from the Data Release 5 of the Sloan Digital Sky Survey (SDSS). We selected their companion candidates from the SDSS imaging data, and classified them into true companions, fore/background galaxies and companion candidates using the SDSS and our KPNO spectra. We observed 26 companion candidates of E+A galaxies at the KPNO to measure their redshifts. Their spectra showed that 17 targets are true companion galaxies.
- ID:
- ivo://CDS.VizieR/J/other/RAA/15.1414
- Title:
- E+A galaxy candidates in LAMOST DR2
- Short Name:
- J/other/RAA/15.1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A sample of 70 E+A galaxies is selected from 37206 galaxies in the second data release of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST). This sample is selected according to the criteria for E+A galaxies defined by Goto, and each of these objects is further visually identified. In this sample, most objects are low redshift E+A galaxies with z<0.25, and are located in an area of the sky with high Galactic latitude and magnitude from 14 to 18mag in the g, r and i bands. A stellar population analysis of the whole sample indicates that the E+A galaxies are characterized by both young and old stellar populations (SPs), and the metal-rich SPs have relatively higher contributions than the metal-poor ones. Additionally, a morphological classification of these objects is performed based on images taken from the Sloan Digital Sky Survey.
- ID:
- ivo://CDS.VizieR/J/MNRAS/444/2571
- Title:
- Early-Tyoe Galaxies in SDSS and GALEX
- Short Name:
- J/MNRAS/444/2571
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use the Hernandez-Perez and Bruzual stellar population synthesis models to study the role of interacting binary pairs as progenitors of extreme horizontal branch (EHB) stars. We assemble a sample of 3417 early-type galaxies observed both in the optical (SDSS-DR8) and the UV (GALEX-GR6). The galaxies in our sample can be classified according to their position in the colour-colour diagram as UV-weak or red-sequence galaxies (~48%), UV-strong or UVX galaxies (~9%), and recent star-forming galaxies (~43%). Analysing this sample using the models for various choices of basic model parameters, we conclude that (a) the UVr colours of UV-weak and UV-strong galaxies are reproduced by the models as long as the fraction of binary stars is at least 15%. (b) Higher metallicity models (Z=0.02 and 0.03) reproduce the colours of UV-weak and UV-strong galaxies better than lower Z models. The Z=0.03 model is slightly bluer than the Z=0.02 model in the UV-strong region, indicating a weak relationship between UVX and Z. (c) The strength of UVX increases with age in the model population. This is at variance with the results of other models that include binary stars as progenitors of EHB stars.
- ID:
- ivo://CDS.VizieR/J/A+A/509/A3
- Title:
- Earth Orientation Catalog 4 (EOC-4)
- Short Name:
- J/A+A/509/A3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The astrometric ground-based observations of latitude / universal time variations, covering the interval 1899.7-2003.0, were used in combination with Hipparcos / Tycho positions and some older ground-based catalogs to construct a family of catalogs, tailored for long-term Earth rotation studies. These catalogs, called Earth Orientation Catalogs (EOC-1 through EOC-3) yielded more accurate proper motions than the original Hipparcos Catalogue, and its latest version, EOC-3, even periodic motions for a large portion of the stars. About 4.5 million observations made at 33 observatories are combined with the catalogs ARIHIP, TYCHO-2 etc... in order to obtain EOC-4. Spectral analysis of ground-based data and comparison with the USNO Sixth Catalog of Orbits of Visual Binary Stars are used to discover which of the observed objects display periodic motions, and improved combination procedures are used. The catalog contains 4418 different objects (i.e., stars, components of double stars, photocenters), out of which 599 have significant orbital motions.
- ID:
- ivo://CDS.VizieR/J/AJ/138/1938
- Title:
- EDD: All Digital HI profile catalog
- Short Name:
- J/AJ/138/1938
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An important component of the Extragalactic Distance Database is a group of catalogs related to the measurement of HI line profile parameters. One of these is the All Digital HI catalog which contains an amalgam of information from new data and old. The new data result from observations with Arecibo and Parkes Telescopes and with the Green Bank Telescope, including continuing input since the award of the NRAO Cosmic Flows Large Program. The old data have been collected from archives, wherever available, particularly the Cornell University Digital HI Archive, the Nancay Telescope extragalactic HI archive, and the Australia Telescope HI archive. The catalog currently contains information on ~15000 profiles relating to ~13000 galaxies. The channel-flux per channel files, from whatever source, is carried through a common pipeline. The derived parameter of greatest interest is W_m50_, the profile width at 50% of the mean flux. After appropriate adjustment, the parameter W_mx_ is derived, the line width that statistically approximates the peak-to-peak maximum rotation velocity before correction for inclination, 2V_max_sini.
- ID:
- ivo://CDS.VizieR/J/A+A/578/A105
- Title:
- EELGs out to z~1 in zCOSMOS
- Short Name:
- J/A+A/578/A105
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present line measurements and physical properties of a sample of 165 extreme emission-line galaxies (EELGs) in the zCOSMOS 20k-Bright Survey (Lilly et al., 2009, Cat. J/ApJS/184/218). The zCOSMOS spectra consist of ~1h integrations in the medium resolution LRRED grism setting (R~600 with 2.5{AA}/pixel), covering a wavelength range 5550<{lambda}<9650{AA}. Measured emission-line fluxes are given in units of 10^-17^erg/s/cm^2^. Flux errors have been derived following Perez-Montero et al. (2013A&A...549A..25P) and Amorin et al. (2012ApJ...749..185A and 2012ApJ...754L..22A). No extinction correction has been applied to these fluxes. For each galaxy the reddening constant, c(H{beta}), is presented. These values and their corresponding uncertainties have been derived from the H{alpha}/H{beta} or H{gamma}/H{beta} ratios, whenever possible. A reddening constant derived from the SED best-fitting was adopted for (a) those galaxies where the computation of c(H{beta}) from emission lines is not possible because of the lack of lines, or (b) the corresponding line ratio produces a negative extinction correction (i.e., Ha/Hb<2.82 or Hg/Hb<0.47, assuming Case B recombination with T_e_=2*10^4K, n_e_=100cm^-3^). Stellar mass and 1{sigma} uncertainties have been obtained from SED fitting (Bolzonella et al., 2010A&A...524A..76B) after removal of the flux contribution from strong emission lines.
- ID:
- ivo://CDS.VizieR/J/A+A/599/A83
- Title:
- ELG and AGN in WINGS clusters
- Short Name:
- J/A+A/599/A83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the analysis of the emission line galaxies members of 46 low-redshift (0.04<z<0.07) clusters observed by WINGS (WIde-field Nearby Galaxy cluster Survey; Fasano et al., 2006A&A...445..805F). Emission line galaxies were identified following criteria that are meant to minimize biases against non-star-forming galaxies and classified employing diagnostic diagrams. We examined the emission line properties and frequencies of star-forming galaxies, transition objects, and active galactic nuclei (AGNs: LINERs and Seyferts), unclassified galaxies with emission lines, and quiescent galaxies with no detectable line emission. A deficit of emission line galaxies in the cluster environment is indicated by both a lower frequency, and a systematically lower Balmer emission line equivalent width and luminosity with respect to control samples; this implies a lower amount of ionized gas per unit mass and a lower star formation rate if the source is classified as Hii region. A sizable population of transition objects and of low-luminosity LINERs (~10-20% of all emission line galaxies) are detected among WINGS cluster galaxies. These sources are a factor of 1.5 more frequent, or at least as frequent, as in control samples with respect to Hii sources. Transition objects and LINERs in clusters are most affected in terms of line equivalent width by the environment and appear predominantly consistent with so-called retired galaxies. Shock heating can be a possible gas excitation mechanism that is able to account for observed line ratios. Specific to the cluster environment, we suggest interaction between atomic and molecular gas and the intracluster medium as a possible physical cause of line-emitting shocks.
- ID:
- ivo://CDS.VizieR/J/A+AS/116/43
- Title:
- Emission-line galaxies nearby voids.
- Short Name:
- J/A+AS/116/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the observational results of our search for emission-line galaxies (ELG) towards nearby voids. In order to find ELG, we started a survey using the IIIa-J objective prism plates from the Hamburg QSO Survey. The plates are digitized and an automatic procedure was applied to select the candidates. Digitized direct plates were used to determine coordinates and to reject overlaps between spectra. The accuracy of the coordinates is +/-2". A total area of 1248deg^2^ was scanned, distributed in four different regions. All the selected objects were observed with follow-up spectroscopy. We have obtained a final sample of 203 objects, of which 196 are emission-line galaxies, four are galaxies with absorption lines and three are QSOs. Almost half of our objects are newly discovered ones and three quarters of the given redshifts are new. Our sample contains mainly high ionization galaxies and is less sensitive in the detection of low-ionization objects. The apparent magnitudes, as derived from the objective prism plates, range between 15.0<=B<=19.5. The sample is dominated by nearby galaxies, with a peak in the redshift distribution at cz=4500 km/s.
- ID:
- ivo://CDS.VizieR/J/ApJ/812/89
- Title:
- Environmental COntext (ECO) catalog
- Short Name:
- J/ApJ/812/89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the relationships between galaxy environments and galaxy properties related to disk (re)growth, considering two highly complete samples that are approximately baryonic mass limited into the high-mass dwarf galaxy regime, the Environmental COntext (ECO) catalog (data release herein) and the B-semester region of the REsolved Spectroscopy Of a Local VolumE (RESOLVE) survey. We quantify galaxy environments using both group identification and smoothed galaxy density field methods. We use by-eye and quantitative morphological classifications plus atomic gas content measurements and estimates. We find that blue early-type (E/S0) galaxies, gas-dominated galaxies, and UV-bright disk host galaxies all become distinctly more common below group halo mass ~10^11.5^M_{sun}_, implying that this low group halo mass regime may be a preferred regime for significant disk growth activity. We also find that blue early-type and blue late-type galaxies inhabit environments of similar group halo mass at fixed baryonic mass, consistent with a scenario in which blue early-types can regrow late-type disks. In fact, we find that the only significant difference in the typical group halo mass inhabited by different galaxy classes is for satellite galaxies with different colors, where at fixed baryonic mass red early- and late-types have higher typical group halo masses than blue early- and late-types. More generally, we argue that the traditional morphology-environment relation (i.e., that denser environments tend to have more early-types) can be largely attributed to the morphology-galaxy mass relation for centrals and the color-environment relation for satellites.
