- 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.
Number of results to display per page
Search Results
- 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/AJ/89/53
- Title:
- E and SO galaxies survey at 2.7 and 5.0 GHz
- Short Name:
- J/AJ/89/53
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper presents results from a continuum radio survey of a complete sample of 248 southern E and S0 galaxies. All the galaxies were observed at 2.7GHz (11cm) with the Parkes radio telescope, and those detected were reobserved at 5.0 GHz (6 cm). Thirty-seven galaxies were detected above a level of 25-30mJy, and a consideration of the background source density at 2.7GHz indicates that no more than two or three of these detections are due to background sources.
- 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/MNRAS/406/382
- Title:
- Early-type galaxies in the SDSS Stripe82
- Short Name:
- J/MNRAS/406/382
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We explore the properties of "peculiar" early-type galaxies (ETGs) in the local Universe that show (faint) morphological signatures of recent interactions such as tidal tails, shells and dust lanes. Standard-depth (~51s exposure) multicolour galaxy images from the Sloan Digital Sky Survey (SDSS) are combined with the significantly (~2mag) deeper monochromatic images from the public SDSS Stripe82 (-50{deg}<{alpha}<59{deg}, -1.25{deg}<{delta}<1.25{deg}) to extract, through careful visual inspection, a robust sample of nearby (z<0.05), luminous (M_r_<-20.5) ETGs, including a subset of ~70 peculiar systems. ~18% of ETGs exhibit signs of disturbed morphologies (e.g. shells), while ~7% show evidence of dust lanes and patches. An analysis of optical emission-line ratios indicates that the fraction of peculiar ETGs that are Seyferts or LINERs (19.4%) is twice the corresponding values in their relaxed counterparts (10.1%). LINER-like emission is the dominant type of nebular activity in all ETG classes, plausibly driven by stellar photoionization associated with recent star formation. An analysis of ultraviolet-optical colours indicates that, regardless of the luminosity range being considered, the fraction of peculiar ETGs that have experienced star formation in the last Gyr is a factor of ~1.5 higher than that in their relaxed counterparts. The spectrophotometric results strongly suggest that the interactions that produce the morphological peculiarities also induce low-level recent star formation which, based on the recent literature, are likely to contribute a few per cent of the stellar mass over the last ~1Gyr. Peculiar ETGs preferentially inhabit low-density environments (outskirts of clusters, groups or the field), either due to high peculiar velocities in clusters making merging unlikely or because shell systems are disrupted through frequent interactions within a cluster crossing time.
- ID:
- ivo://CDS.VizieR/J/A+A/330/423
- Title:
- Early-type galaxies kinematics
- Short Name:
- J/A+A/330/423
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present data on the stellar kinematics of the brightest ellipticals in HCG 62, HCG 68, NGC 2300 groups. Moreover, we report on ASCA GIS as well as optical observations of the early-type member of the pair K 416 (NGC 5480/5481) similar, in many respects, to the dominant pair in the NGC 2300 group. The kinematics of HCG 62a/b and HCG 68a/b indicate that they are not interacting pairs. HCG 62a is instead possibly interacting with HCG 62c, as suggested by their morphology (see Mendes de Oliveira and Hickson 1994), In contrast to the results for the NGC 2300/2276 group, ASCA observations indicate a significant absence of hot gas in the K 416 system. Whether the NGC 2300 multiplet is viewed as a loose group or as a massive E+S pair, it is clear that similar morphological entities do not always show similar X-ray properties. Under the hypothesis that diffuse X-ray emission marks the group potential, we consider the possibility that K 416 is an unbound encounter. In this scenario, morphological distortions are indicative of the ongoing interaction, but are only circumstantially correlated with the physical reality of a pair/multiplet as a bound system.
- ID:
- ivo://CDS.VizieR/J/A+A/342/671
- Title:
- Early-type spiral galaxies kinematics
- Short Name:
- J/A+A/342/671
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the stellar and ionized-gas velocity curves and velocity-dispersion profiles along the major axis for six early-type spiral galaxies. Two of these galaxies, namely NGC 2179 and NGC 2775, are particularly suited for the study of dark matter halos. Using their luminosity profiles and modeling their stellar and gaseous kinematics, we derive the mass contributions of the luminous and the dark matter to the total potential. In NGC 2179 we find that the data (measured out to about the optical radius R_opt_) unambiguously require the presence of a massive dark halo. For the brighter and bigger object NGC 2775, we can rule out a significant halo contribution at radii R<~0.6R_opt_. Although preliminary, these results agree with the familiar mass distribution trend known for late-type spirals of comparable mass.
- ID:
- ivo://CDS.VizieR/J/ApJ/642/L13
- Title:
- ECDFS MUSYC galaxies UBVRIzNB5000 photometry
- Short Name:
- J/ApJ/642/L13
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We selected 40 candidate Ly{alpha}-emitting galaxies (LAEs) at z~3.1 with observed-frame equivalent widths greater than 150{AA} and inferred emission-line fluxes above 2.5x10^-17^ergs/cm^2^/s from deep narrowband and broadband MUSYC images of the Extended Chandra Deep Field South. Covering 992-arcmin^2^, this is the largest "blank field" surveyed for LAEs at z~3, allowing an improved estimate of the space density of this population of (3+/-1)x10^4^h/Mpc^3^. Spectroscopic follow-up of 23 candidates yielded 18 redshifts, all at z~3.1. Over 80% of the LAEs are dimmer in continuum magnitude than the typical Lyman break galaxy (LBG) spectroscopic limit of R=25.5 (AB), with a median continuum magnitude R~27 and very blue continuum colors, V-z~=0.
- ID:
- ivo://CDS.VizieR/J/ApJS/248/33
- Title:
- Edge-on HI-rich LSB galaxies from ALFALFA
- Short Name:
- J/ApJS/248/33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Low surface brightness galaxies (LSBGs) are defined as galaxies that are fainter than dark night sky and are important for studying our universe. Particularly, edge-on galaxies are useful for the study of rotational velocity and dynamical properties of galaxies. Hence here we focus on searching for edge-on LSBGs. In order to find these edge-on dim galaxies, a series of effects caused by inclination, including the surface brightness profile, internal extinction, and scale length, have been corrected. In this work, we present a catalog of 281 edge-on LSBG candidates, which are selected from the crossmatch between Sloan Digital Sky Survey Data Release 7 and the 40% ALFALFA catalog. We also present the properties of these edge-on LSBG candidates including the absolute magnitude, central surface brightness, B-V color, scale length, and relative thickness. Our result suggests that the correction of inclination effects is very important for obtaining a complete sample of LSBGs.
- ID:
- ivo://CDS.VizieR/J/ApJS/111/163
- Title:
- Einstein X-ray survey of galaxies. I.
- Short Name:
- J/ApJS/111/163
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a complete Einstein imaging proportional counter X-ray survey of optically-selected galaxies from the Shapley-Ames Catalog (Cat. <VII/112>), the Uppsala General Catalog (Cat. <VII/26>) and the European Southern Observatory Catalog (Cat. <VII/115>). Well-defined optical criteria are used to select the galaxies, and X-ray fluxes are measured at the optically-defined positions. The result is a comprehensive list of X-ray detection and upper limit measurements for 1018 galaxies. Of these, 827 have either independent distance estimates or radial velocities. Associated optical, redshift, and distance data have been assembled for these galaxies, and their distances come from a combination of directly predicted distances and those predicted from the Faber-Burstein Great Attractor/Virgocentric infall model. The accuracy of the X-ray fluxes has been checked in three different ways; all are consistent with the derived X-ray fluxes being of <=0.1 dex accuracy. In particular, there is agreement with previously published X-ray fluxes for galaxies in common with a 1991 study by Roberts et al. (1991ApJS...75..751R) and a 1992 study by Fabbiano et al. (1992ApJS...80..531F).The data presented here will be used in further studies to characterize the X-ray output of galaxies of various morphological types and thus to enable the determination of the major sources contributing to the X-ray emission from galaxies.