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2351. Monochromatic conversion factors to LIR & Mdust
ID:
ivo://CDS.VizieR/J/A+A/609/A30
Title:
Monochromatic conversion factors to LIR & Mdust
Short Name:
J/A+A/609/A30
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new, publicly available library of dust spectral energy distributions (SEDs). These SEDs are characterized by only three parameters: the dust mass (Mdust), the dust temperature (Tdust), and the mid-to-total infrared color (IR8=LIR/L8). The latter measures the relative contribution of polycyclic aromatic hydrocarbon (PAH) molecules to the total infrared luminosity. We used this library to model star-forming galaxies at 0.5<z<4 in the deep CANDELS fields, using both individual detections and stacks of Herschel and ALMA imaging, and extending this sample to z=0 using the Herschel Reference Survey. At first order, the dust SED of a galaxy was observed to be independent of stellar mass, but evolving with redshift. We found trends of increasing Tdust and IR8 with redshift and distance from the SFR-M* main sequence, and quantified for the first time their intrinsic scatter. Half of the observed variations of these parameters was captured by the above empirical relations, and after subtracting the measurement errors we found residual scatters of {delta}Tdust/Tdust=12% and {delta}logIR8=0.18dex. We observed second order variations with stellar mass: massive galaxies (M*>10^119M_{sun}_) at z<=1 have slightly lower temperatures indicative of a reduced star formation efficiency, while low mass galaxies (M*<10^10^M_{sun}_) at z>=1 showed reduced PAH emission, possibly linked to their lower metallicities. Building on these results, we constructed high-fidelity mock galaxy catalogs to predict the accuracy of infrared luminosities and dust masses determined using a single broadband measurement. Using a single James Webb Space Telescope (JWST) MIRI band, we found that LIR is typically uncertain by 0.15dex, with a maximum of 0.25dex when probing the rest-frame 8um, and this is not significantly impacted by typical redshift uncertainties. On the other hand, we found that ALMA bands 8 to 7 and 6 to 3 measured the dust mass at better than 0.2 and 0.15dex, respectively, and independently of redshift, while bands 9 to 6 only measured LIR at better than 0.2dex at z>1, 3.2, 3.8, and 5.7, respectively. Starburst galaxies had their LIR significantly underestimated when measured by a single JWST or ALMA band, while their dust mass from a single ALMA band were moderately overestimated. This dust library and the results of this paper can be used immediately to improve the design of observing proposals, and interpret more accurately the large amount of archival data from Spitzer, Herschel and ALMA.
2352. Montreal Blue Galaxy Survey
ID:
ivo://CDS.VizieR/J/AJ/105/35
Title:
Montreal Blue Galaxy Survey
Short Name:
J/AJ/105/35
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe and present the first results of a UV-bright galaxy survey using the Montreal-Cambridge-Tololo (MCT) plate collection. Visual inspection of 57 CTIO Curtis Schmidt plates, covering more than 1300 sq. deg., has resulted in the identification of 95 UV-bright galaxies brighter than B = 15.5. Even though 80% of these objects are IRAS sources, barely 20% have their nature already established. The initial result of our survey shows that the bulk of our UV-bright candidates are narrow emission-line galaxies commonly known as starburst or HII galaxies. The fraction of AGNs found is somewhat less than 10%, but comparable to what has been found by the Markarian survey. We expect to find approximately 500 UV-bright galaxies in the 7000 sq. deg. of The MCT Survey with b < -40 deg. As we go further south, a large number of bright new objects will be discovered.
2353. Montreal Blue Galaxy Survey. II.
ID:
ivo://CDS.VizieR/J/AJ/108/405
Title:
Montreal Blue Galaxy Survey. II.
Short Name:
J/AJ/108/405
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present and discuss the second list of the Montreal Blue Galaxy survey. Following the inspection of 71 plates, we found 237 new candidates with B<15.5. 73 percent of them are also detected by IRAS. Spectrophotometry was carried out, at medium resolution, for a subset of 40 objects leading to the identification of three new AGNs and producing 13 new radial velocities. Spectral classification of our candidates confirms our previous finding that the majority of our candidates are starburst nucleus galaxies similar to the objects studied by Balzano [1983ApJ...268..602B]. Our survey is biased against the high excitation starburst H II galaxies and the LINER galaxies. Metallicities of our galaxies are found to be from log(O/H)=8.4 to 9.0, which suggests galaxies in advanced stages of chemical evolution.
2354. Morphological analysis of HDF-N and HDF-S
ID:
ivo://CDS.VizieR/J/MNRAS/355/82
Title:
Morphological analysis of HDF-N and HDF-S
Short Name:
J/MNRAS/355/82
Date:
21 Oct 2021
Publisher:
CDS
Description:
Based on drizzled F606W and F814W images, we present quantitative structural parameters in the V-band rest-frame for all galaxies with z<1 and I_814_(AB)<24.5mag in the Hubble Deep Fields North and South. Our structural parameters are based on a two-component surface brightness distribution using a Sersic bulge and an exponential disc. Detailed simulations and comparisons with previous work are presented.
2355. Morphological Cat. of Gal. (MCG)
ID:
ivo://CDS.VizieR/VII/62A
Title:
Morphological Cat. of Gal. (MCG)
Short Name:
VII/62A
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog is a compilation of information for approximately 34000 galaxies found and examined on the Palomar Observatory Sky Survey (POSS). Individual identifiers are assigned for about 29000 galaxies and information on the remaining 5000 is present in the extensive notes of the published catalogs (Vorontsov-Velyaminov et al. 1962-1968). The catalog is structured according to the POSS zones, counting from the equator, and is numbered from +15 (corresponding to +90 deg) to +01 (+06 zone) and +00 (equatorial zone) to -05 (-30 zone); the fields are numbered with increasing right ascension. The catalog includes cross-identifications to the NGC (Dreyer 1888) and IC (Dreyer 1895, 1908) catalogs, equatorial coordinates for B1950.0, magnitudes, estimated sizes and intensities of the brighter inner region and the entire object, and estimated inclinations.
2356. Morphological classifications of APM galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/274/1107
Title:
Morphological classifications of APM galaxies
Short Name:
J/MNRAS/274/1107
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the consistency of visual morphological classifications of galaxies by comparing classifications for 831 galaxies from six independent observers. The galaxies were classified on laser print copy images or on computer screen using scans made with the Automated Plate Measuring (APM) machine. Classifications are compared using the Revised Hubble numerical type index T. We find that individual observers agree with one another with rms combined dispersions of between 1.3 and 2.3 type units, typically about 1.8 units. The dispersions tend to decrease slightly with increasing angular diameter and, in some cases, with increasing axial ratio (b/a). The agreement between independent observers is reasonably good but the scatter is non-negligible. In spite of the scatter, the Revised Hubble T system can be used to train an automated galaxy classifier, e.g. an artificial neural network, to handle the large number of galaxy images that are being compiled in the APM and other surveys.
2357. Morphologically classified galaxies from SDSS DR3
ID:
ivo://CDS.VizieR/J/AJ/134/579
Title:
Morphologically classified galaxies from SDSS DR3
Short Name:
J/AJ/134/579
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of morphologically classified bright galaxies in the north equatorial stripe (230deg^2^) derived from the Third Data Release of the Sloan Digital Sky Survey (SDSS). Morphological classification is performed by visual inspection of images in the g band. The catalog contains 2253 galaxies complete to a magnitude limit of r=16 after Galactic extinction correction, selected from 2658 objects that are judged to be extended in the photometric catalog in the same magnitude limit. A total of 1866 galaxies in our catalog have spectroscopic information. A brief statistical analysis is presented for the frequency of morphological types and mean colors in the catalog. A visual inspection of the images reveals that the rate of interacting galaxies in the local universe is approximately 1.5% in the r<=16 sample. A verification is made for the photometric catalog generated by the SDSS, especially as to its bright-end completeness.
2358. Morphological parameters of galaxies from Spitzer
ID:
ivo://CDS.VizieR/J/ApJ/781/12
Title:
Morphological parameters of galaxies from Spitzer
Short Name:
J/ApJ/781/12
Date:
21 Oct 2021
Publisher:
CDS
Description:
The morphology of galaxies can be quantified to some degree using a set of scale-invariant parameters. Concentration (C), asymmetry (A), smoothness (S), the Gini index (G), the relative contribution of the brightest pixels to the second-order moment of the flux (M_20_), ellipticity (E), and the Gini index of the second-order moment (G_M_) have all been applied to morphologically classify galaxies at various wavelengths. Here, we present a catalog of these parameters for the Spitzer Survey of stellar structure in Galaxies, a volume-limited, near-infrared (NIR) imaging survey of nearby galaxies using the 3.6 and 4.5{mu}m channels of the Infrared Array Camera on board the Spitzer Space Telescope. Our goal is to provide a reference catalog of NIR quantified morphology for high-redshift studies and galaxy evolution models with enough detail to resolve stellar mass morphology. We explore where normal, non-interacting galaxies--those typically found on the Hubble tuning fork--lie in this parameter space and show that there is a tight relation between concentration (C_82_) and M_20_ for normal galaxies. M_20_ can be used to classify galaxies into earlier and later types (i.e., to separate spirals from irregulars). Several criteria using these parameters exist to select systems with a disturbed morphology, i.e., those that appear to be undergoing a tidal interaction. We examine the applicability of these criteria to Spitzer NIR imaging. We find that four relations, based on the parameters A and S, G and M_20_, G_M_, C, and M_20_, respectively, select outliers in morphological parameter space, but each selects different subsets of galaxies. Two criteria (G_M_>0.6,G>-0.115xM_20_+0.384) seem most appropriate to identify possible mergers and the merger fraction in NIR surveys. We find no strong relation between lopsidedness and most of these morphological parameters, except for a weak dependence of lopsidedness on concentration and M_20_.
2359. Morphological parameters of galaxies with GALEX
ID:
ivo://CDS.VizieR/J/ApJ/864/123
Title:
Morphological parameters of galaxies with GALEX
Short Name:
J/ApJ/864/123
Date:
21 Oct 2021
Publisher:
CDS
Description:
Evolutionary studies that compare galaxy structure as a function of redshift are complicated by the fact that any particular galaxy's appearance depends in part on the rest-frame wavelength of the observation. This leads to the necessity for a "morphological k-correction" between different passbands, especially when comparing the rest-frame optical or infrared (IR) to the ultraviolet (UV). This is of particular concern for high-redshift studies that are conducted in the rest-frame UV. We investigate the effects of this "bandpass shifting" out of the UV by quantifying nearby galaxy structure via concentration, asymmetry, and clumpiness (CAS) parameters. For this study we combine panchromatic data from the UV through the near-IR with Galaxy Evolution Explorer (GALEX) data of 2073 nearby galaxies in the "near-UV" (NUV; ~230nm) and 1127 in the "far-UV" (FUV; ~150nm), providing the largest study of this kind in the mid- to far-UV. We find a relationship between the CAS parameters and observed rest-frame wavelength that make galaxies appear more late-type at shorter wavelengths, particularly in the UV. The effect is strongest for E/S0 galaxies in the far-UV, which have concentrations and asymmetries that more closely resemble those of spiral and peculiar/merging galaxies in the optical. This may be explained by extended disks containing recent star formation. Here, we also release the CAS values of the galaxies imaged in GALEX NUV and FUV for use in comparisons with deep Hubble Space Telescope imaging and the James Webb Space Telescope in the future.
2360. Morphological parameters of WHISP galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/416/2415
Title:
Morphological parameters of WHISP galaxies
Short Name:
J/MNRAS/416/2415
Date:
21 Oct 2021
Publisher:
CDS
Description:
Lopsidedness of the gaseous disc of spiral galaxies is a common phenomenon in disc morphology, profile and kinematics. Simultaneously, the asymmetry of a galaxy's stellar disc, in combination with other morphological parameters, has seen extensive use as an indication of recent merger or interaction in galaxy samples. Quantified morphology of stellar spiral discs is one avenue to determine the merger rate over much of the age of the Universe. In this paper, we measure the quantitative morphology parameters for the HI column density maps from the Westerbork observations of neutral Hydrogen in Irregular and SPiral galaxies (WHISP). These are Concentration, Asymmetry, Smoothness, Gini, M20 and one addition of our own, the Gini parameter of the second-order moment (GM). Our aim is to determine if lopsided or interacting discs can be identified with these parameters. Our sample of 141 HI maps have all previous classifications on their lopsidedness and interaction.

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