- ID:
- ivo://CDS.VizieR/J/MNRAS/478/4657
- Title:
- Structural properties of faint LSB galaxies
- Short Name:
- J/MNRAS/478/4657
- Date:
- 10 Dec 2021 13:47:50
- Publisher:
- CDS
- Description:
- We study the structural properties of Low-Surface-Brightness galaxies (LSB) using a sample of 263 galaxies observed by the Green Bank Telescope. We perform 2D decompositions of these galaxies in the Sloan Digital Sky Survey g, r, and i bands using the GALFIT software. Our decomposition reveals that about 60 per cent of these galaxies are bulgeless i.e. their light distributions are well modelled by pure exponential discs. The rest of the galaxies were fitted with two components: a Sersic bulge and an exponential disc. Most of these galaxies have bulge-to-total (B/T) ratio less than 0.1. However, of these 104 galaxies, 20 per cent have B/T>0.1 i.e. hosting significant bulge component and they are more prominent amongst the fainter LSBs. According to g-r colour criteria, most of the LSB galaxies in our sample are blue, with only 7 classified as red LSBs. About 15 per cent of the LSB galaxies (including both blue and red) in our sample host stellar bars. The incidence of bars is more prominent in relatively massive blue LSB galaxies with very high gas fraction. These findings may provide important clues to the formation and evolution of LSB galaxies - in particular on the bar/bulge formation in faint LSB discs.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/129/682
- Title:
- Structural properties of S+S galaxies
- Short Name:
- J/AJ/129/682
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a structural analysis of nearby galaxies in spiral-spiral pairs in optical BVRI bands and compare them with the structures of isolated spiral galaxies and galaxies in ongoing mergers. We use these comparisons to determine how galaxy structure changes during galaxy interactions and mergers. We analyze light concentration (C), asymmetry (A), and clumpiness (S) parameters, and use the projections of CAS parameter space to compare these samples.
- ID:
- ivo://CDS.VizieR/J/MNRAS/423/962
- Title:
- Structure and dynamics of 8 low SB disc galaxies
- Short Name:
- J/MNRAS/423/962
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the radial profiles of the H{alpha}, Mg and Fe line-strength indices for a sample of eight spiral galaxies with a low-surface-brightness stellar disc and a bulge. The correlations between the central values of the line-strength indices and velocity dispersion are consistent with those known for early-type galaxies and bulges of high-surface-brightness galaxies. The age, metallicity and {alpha}/Fe enhancement of the stellar populations in the bulge-dominated region are obtained using stellar population models with variable element abundance ratios.
- ID:
- ivo://CDS.VizieR/J/MNRAS/358/1116
- Title:
- Structure of early-type galaxies
- Short Name:
- J/MNRAS/358/1116
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the Photometric Plane (PHP), namely the relation between the effective radius r_e_, the mean surface brightness within that radius {mu}_e_ and the Sersic index n, in optical (R and I) and near-infrared (NIR; K) bands for a large sample of early-type galaxies (ETGs) in the rich cluster MS 1008 at z=0.306.
- ID:
- ivo://CDS.VizieR/J/ApJ/899/89
- Title:
- Structure of 1263 galaxies in Stripe 82 region
- Short Name:
- J/ApJ/899/89
- Date:
- 07 Mar 2022 13:26:50
- Publisher:
- CDS
- Description:
- Establishing a correlation (or lack thereof) between the bimodal color distribution of galaxies and their structural parameters is crucial to understand the origin of bimodality. To achieve that, we have performed a 2D mass-based structural decomposition (bulge+disk) of all disk galaxies (total=1263) in the Herschel imaging area of the Stripe 82 region using Ks-band images from the VICS82 survey. The scaling relations thus derived are found to reflect the internal kinematics and are employed in combination to select an indubitable set of classical- and pseudo-bulge-hosting disk galaxies. The rest of the galaxies (<20%) are marked as disks with "ambiguous" bulges. Pseudo- and classical bulge-disk galaxies exhibit clear bimodality in terms of all stellar parameters (M*, specific star formation rate, r-Ks). All pseudo- bulge-disk galaxies are blue and star forming, and all classical bulge-disk galaxies are red and quiescent with less than 5% digressions. Ambiguous bulge- disk galaxies are intermediate to pseudo- and classical bulge-disk galaxies in the distribution of all structural and stellar parameters. {Delta}<{mu}_eb_>-based on the placement of bulges on the Kormendy relation-is found to be the most efficient single structural indicator of both bulge type and stellar activity. The placement of ambiguous bulge-disk galaxies on scaling relations and the fundamental plane, in addition to their peculiar stellar properties, suggests that they are dominantly part of the green valley.
- ID:
- ivo://CDS.VizieR/J/ApJ/889/80
- Title:
- STUDIES. III. SCUBA-2 450um gal. with MIPS & VLA obs.
- Short Name:
- J/ApJ/889/80
- Date:
- 11 Mar 2022
- Publisher:
- CDS
- Description:
- We construct a SCUBA-2 450{mu}m map in the COSMOS field that covers an area of 300arcmin^2^ and reaches a 1{sigma} noise level of 0.65mJy in the deepest region. We extract 256 sources detected at 450{mu}m with signal-to-noise ratios >4.0 and analyze the physical properties of their multiwavelength counterparts. We find that most of the sources are at z<~3, with a median of z=1.79_-0.15_^+0.03^%. About 35_-25_^+32^% of our sources are classified as starburst galaxies based on their total star formation rates (SFRs) and stellar masses (M_*_). By fitting the far-infrared spectral energy distributions, we find that our 450{mu}m selected sample has a wide range of dust temperatures (20K<~T_d_<~60K), with a median of T_d_=38.3_-0.9_^+0.4^K. We do not find a redshift evolution in dust temperature for sources with L_IR_>10^12^L_{sun}_ at z<3. However, we find a moderate correlation where the dust temperature increases with the deviation from the SFR-M_*_ relation. The increase in dust temperature also correlates with optical morphology, which is consistent with merger-triggered starbursts in submillimeter galaxies. Our galaxies do not show the tight IRX-{beta}_UV_ correlation that has been observed in the local universe. We construct the infrared luminosity functions of our 450{mu}m sources and measure their comoving SFR densities (SFRDs). The contribution of the L_IR_>10^12^L_{sun}_ population to the SFRD rises dramatically from z=0 to 2 ({propto}(1+z)^3.9+/-1.1^) and dominates the total SFRD at z>~2.
- ID:
- ivo://CDS.VizieR/J/ApJ/865/103
- Title:
- STUDIES. II. NIR morphologies of submm galaxies
- Short Name:
- J/ApJ/865/103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present structural parameters and morphological properties of faint 450{mu}m selected submillimeter galaxies (SMGs) from the JCMT Large Program, STUDIES, in the COSMOS-CANDELS region. Their properties are compared to an 850{mu}m selected and a matched star-forming samples. We investigate stellar structures of 169 faint 450{mu}m sources (S_450_=2.8-29.6mJy; S/N>4) at z<3 using HST near-infrared observations. Based on our spectral energy distribution fitting, half of such faint SMGs (L_IR_=10^11.65^+/-0.98^L_{sun}_) lie above the star formation rate (SFR)/stellar mass plane. The size-mass relation shows that these SMGs are generally similar to less-luminous star-forming galaxies selected by NUV-r versus r-J colors. Because of the intrinsic luminosity of the sample, their rest-frame optical emission is less extended than the 850{mu}m sources (S_850_>2mJy) and more extended than the star-forming galaxies in the same redshift range. For the stellar mass and SFR-matched sample at z~1 and z~2, the size differences are marginal between faint SMGs and the matched galaxies. Moreover, faint SMGs have similar Sersic indices and projected axis ratios as star-forming galaxies with the same stellar mass and SFR. Both SMGs and the matched galaxies show high fractions (~70%) of disturbed features at z~2, and the fractions depend on the SFRs. These suggest that their star formation activity is related to galaxy merging and the stellar structures of SMGs are similar to those of star-forming galaxies. We show that the depths of submillimeter surveys are approaching the lower luminosity end of star-forming galaxies, allowing us to detect galaxies on the main sequence.
- ID:
- ivo://CDS.VizieR/J/AZh/77/3
- Title:
- Studies of Bright Steep-Spectrum Radio Sources
- Short Name:
- J/AZh/77/3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of studies of bright radio sources in the constellation Cetus are presented. More than 50% of the sources have radio spectral indices steeper than 0.9. Optical identifications have been determined for 35 sources. A large fraction of the radio sources are identified with weak blue galaxies. Given their spectral indices, it is likely that these objects have redshift z=0.4-1.0. More than 20% of the steep-spectrum sources do not have optical identifications and appear to be weak galaxies with z>2.
- ID:
- ivo://CDS.VizieR/III/147
- Title:
- Studies of LMC stellar content
- Short Name:
- III/147
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A spectral survey has been made during the period 1971 to 1975 with the ESO 40cm astrograph at La Silla, equipped with its normal prism, giving an intermediate dispersion of 95Angstroem/mm at 4026Angstroem. Long exposure plates taken directly or with an interference filter enabled us to obtain spectral types for nearly 1600 stars. In parallel, a V photographic survey has been carried out during the same period with the same astrograph and has led to the determination of V magnitudes for more that 700 stars having no previous photometric data. New spectroscopic and photometric results as well as previous photoelectric UBV values are given in the catalogue together with additional remarks concerning peculiarities of spectra, V magnitudes, and details on double and multiple systems.
- ID:
- ivo://CDS.VizieR/J/MNRAS/414/3699
- Title:
- Study of hot stellar systems and galaxies
- Short Name:
- J/MNRAS/414/3699
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a complete picture of dynamically hot stellar systems, ranging from faint galaxies and star clusters of only a few hundred solar masses up to giant elliptical galaxies, in particular including large samples of compact elliptical galaxies (cEs), ultra-compact dwarf galaxies (UCDs), dwarf elliptical galaxies (dEs) of nearby galaxy clusters, and Local Group ultra-faint dwarf spheroidal galaxies (dSphs). For all those stellar systems we show the effective radius-luminosity, effective radius-stellar mass, and effective mass surface density-stellar mass plane.
