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1111. GaLactic and Extragalactic All-sky MWA survey
ID:
ivo://CDS.VizieR/VIII/100
Title:
GaLactic and Extragalactic All-sky MWA survey
Short Name:
VIII/100
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the Murchison Widefield Array (MWA), the low-frequency Square Kilometre Array (SKA1 LOW) precursor located in Western Australia, we have completed the GaLactic and Extragalactic All-sky MWA (GLEAM) survey, and present the resulting extragalactic catalogue, utilising the first year of observations. The catalogue covers 24,402 square degrees, over declinations south of +30{deg} and Galactic latitudes outside 10{deg} of the Galactic plane, excluding some areas such as the Magellanic Clouds. It contains 307,456 radio sources with 20 separate flux density measurements across 72-231MHz, selected from a time- and frequency- integrated image centred at 200MHz, with a resolution of ~=2'. Over the catalogued region, we estimate that the catalogue is 90% complete at 170mJy, and 50% complete at 55mJy, and large areas are complete at even lower flux density levels. Its reliability is 99.97% above the detection threshold of 5{sigma}, which itself is typically 50mJy. These observations constitute the widest fractional bandwidth and largest sky area survey at radio frequencies to date, and calibrate the low frequency flux density scale of the southern sky to better than 10%. This paper presents details of the flagging, imaging, mosaicking, and source extraction/characterisation, as well as estimates of the completeness and reliability. All source measurements and images are available online. This is the first in a series of publications describing the GLEAM survey results.
1112. Galactic Cepheids and RR Lyrae multiplicity. II
ID:
ivo://CDS.VizieR/J/A+A/623/A117
Title:
Galactic Cepheids and RR Lyrae multiplicity. II
Short Name:
J/A+A/623/A117
Date:
21 Oct 2021
Publisher:
CDS
Description:
The multiplicity of Classical Cepheids (CCs) and RR Lyrae stars (RRLs) is still imperfectly known, particularly for RRLs. In order to complement the close-in short orbital period systems presented in Paper I (Kervella et al., 2019, Cat. J/A+A/623/A16), we aim at detecting the wide, spatially resolved companions of the targets of our reference samples of Galactic CCs and RRLs. Angularly resolved common proper motion pairs are detected using a simple progressive selection algorithm to separate the most probable candidate companions from the unrelated field stars. We detect 27 resolved, high probability gravitationally bound systems with CCs out of 456 examined stars, and one unbound star embedded in the circumstellar dusty nebula of the long-period Cepheid RS Pup. We find 7 spatially resolved, probable bound systems with RRL primaries out of 789 investigated stars, and 22 additional candidate pairs. We report in particular new companions of three bright RRLs: OV And (companion of F4V spectral type), RR Leo (M0V) and SS Oct (K2V). In addition, we discovered resolved companions of 14 stars of various variability classes that were misclassified as RRLs. The detection of resolved common proper motion companions around CCs and RRLs facilitates the validation of their GDR2 parallaxes. The possibility to conduct a detailed analysis of the resolved coeval companions of CCs and old population RRLs will also be valuable to progress on our understanding of their evolutionary path.
1113. Galactic extinction at low Galactic latitudes
ID:
ivo://CDS.VizieR/J/MNRAS/503/5351
Title:
Galactic extinction at low Galactic latitudes
Short Name:
J/MNRAS/503/5351
Date:
19 Jan 2022 00:31:53
Publisher:
CDS
Description:
We use near-infrared (J-K) colours of bright 2MASS galaxies, measured within a 7-arcsec-radius aperture, to calibrate the Schlegel, Finkbeiner & Davis DIRBE/IRAS Galactic extinction map at low Galactic latitudes (|b|<10{deg}). Using 3460 galaxies covering a large range in extinction (up to A_K_=1.15mag or E(B-V)~=3.19mag), we derive a correction factor f=0.83+/-0.01 by fitting a linear regression to the colour-extinction relation, confirming that the Schlegel et al. maps overestimate the extinction. We argue that the use of only a small range in extinction (e.g., A_K_<0.4mag) increases the uncertainty in the correction factor and may overestimate it. Our data confirm the Fitzpatrick extinction law for the J- and K-band. We also tested four all-sky extinction maps based on Planck satellite data. All maps require a correction factor as well. In three cases, the application of the respective extinction correction to the galaxy colours results in a reduced scatter in the colour-extinction relation, indicating a more reliable extinction correction. Finally, the large galaxy sample allows an analysis of the calibration of the extinction maps as a function of Galactic longitude and latitude. For all but one extinction map, we find a marked offset between the Galactic Centre and Anticentre region, but not with the dipole of the cosmic microwave background. Based on our analysis, we recommend the use of the GNILC extinction map by Planck Collaboration XLVIII with a correction factor f=0.86+/-0.01.
1114. Galactic reddening maps
ID:
ivo://CDS.VizieR/J/PASP/111/57
Title:
Galactic reddening maps
Short Name:
J/PASP/111/57
Date:
21 Oct 2021
Publisher:
CDS
Description:
Accurate maps of Galactic reddening are important for a number of applications, such as mapping the peculiar velocity field in the nearby universe. Of particular concern are systematic errors which vary slowly as a function of position on the sky, as these would induce spurious bulk flow. We have compared the reddenings of Burstein & Heiles (BH, 1982, Cat. <J/AJ/87/1165>) and those of Schlegel, Finkbeiner, & Davis (1998ApJ...500..525S, SFD) to independent estimates of the reddening, for Galactic latitudes |b|>10{deg}. Our primary source of Galactic reddening estimates comes from comparing the difference between the observed B-V colors of early-type galaxies, and the predicted B-V color determined from the B-V-Mg_2_ relation. We have fitted a dipole to the residuals in order to look for large-scale systematic deviations. There is marginal evidence for a dipolar residual in the comparison between the SFD maps and the observed early-type galaxy reddenings. If this is due to an error in the SFD maps, then it can be corrected with a small (13%) multiplicative dipole term. We argue, however, that this difference is more likely to be due to a small (0.01mag) systematic error in the measured B-V colors of the early-type galaxies. This interpretation is supported by a smaller, independent data set (globular cluster and RR Lyrae stars), which yields a result inconsistent with the early-type galaxy residual dipole. BH reddenings are found to have no significant systematic residuals, apart from the known problem in the region 230{deg}<l<310{deg}, -20{deg}<b<20{deg}.
1115. Galactic rotation curve from selected maser
ID:
ivo://CDS.VizieR/J/PAZh/37/281
Title:
Galactic rotation curve from selected maser
Short Name:
J/PAZh/37/281
Date:
21 Oct 2021
Publisher:
CDS
Description:
Based on currently available observations of 28 maser sources in 25 star-forming regions with measured trigonometric parallaxes, proper motions, and radial velocities, we have constructed the rotation curve of the Galaxy. Taking different distances to the Galactic center R_0_, we have estimated the peculiar velocity of the Sun, the angular velocity of Galactic rotation, and its three derivatives.
1116. Galaxies and QSOs FIR size and surface brightness
ID:
ivo://CDS.VizieR/J/A+A/591/A136
Title:
Galaxies and QSOs FIR size and surface brightness
Short Name:
J/A+A/591/A136
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use Herschel 70 to 160{mu}m images to study the size of the far-infrared emitting region in about 400 local galaxies and quasar (QSO) hosts. The sample includes normal "main-sequence" star-forming galaxies, as well as infrared luminous galaxies and Palomar-Green QSOs, with different levels and structures of star formation. Assuming Gaussian spatial distribution of the far-infrared (FIR) emission, the excellent stability of the Herschel point spread function (PSF) enables us to measure sizes well below the PSF width, by subtracting widths in quadrature. We derive scalings of FIR size and surface brightness of local galaxies with FIR luminosity, with distance from the star-forming main-sequence, and with FIR color. Luminosities L_FIR_~10^11^L_{sun}_ can be reached with a variety of structures spanning 2dex in size. Ultraluminous L_FIR_~10^12^L_{sun}_ galaxies far above the main-sequence inevitably have small R_e,70_~0.5kpc FIR emitting regions with large surface brightness, and can be close to optically thick in the FIR on average over these regions. Compared to these local relations, first ALMA sizes for the dust emission regions in high redshift galaxies, measured at somewhat longer rest wavelengths, suggest larger sizes at the same IR luminosity. We report a remarkably tight relation with 0.15dex scatter between FIR surface brightness and the ratio of [CII] 158{mu}m emission and FIR emission - the so-called [CII]-deficit is more tightly linked to surface brightness than to FIR luminosity or FIR color. Among 33 z<=0.1 PG QSOs with typical L_FIR_/L_Bol,AGN_~0.1, 19 have a measured 70{mu}m half light radius, with median R_e,70_=1.1kpc. This is consistent with the FIR size for galaxies with similar L_FIR_ but lacking a QSO, in accordance with a scenario where the rest FIR emission of these types of QSOs is, in most cases, due to host star formation.
1117. Galaxies angular momentum evolution
ID:
ivo://CDS.VizieR/J/MNRAS/467/3140
Title:
Galaxies angular momentum evolution
Short Name:
J/MNRAS/467/3140
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a MUSE (Multi-Unit Spectroscopic Explorer) and KMOS (K-band Multi-Object Spectrograph) dynamical study 405 star-forming galaxies at redshift z=0.28-1.65 (median redshift <z>=0.84). Our sample is representative of the star-forming 'main sequence', with star formation rates of SFR=0.1-30M_{sun}_/yr and stellar masses M*=10^8^-10^11^M_{sun}_. For 49+/-4 per cent of our sample, the dynamics suggest rotational support, 24+/-3 per cent are unresolved systems and 5+/-2 per cent appear to be early-stage major mergers with components on 8-30kpc scales. The remaining 22+/-5 per cent appear to be dynamically complex, irregular (or face-on systems). For galaxies whose dynamics suggest rotational support, we derive inclination-corrected rotational velocities and show that these systems lie on a similar scaling between stellar mass and specific angular momentum as local spirals with j*=J/M*{prop.to}M*^2/3^ but with a redshift evolution that scales as j*{prop.to}M*^2/3^(1+z)^-1^. We also identify a correlation between specific angular momentum and disc stability such that galaxies with the highest specific angular momentum (log(j*/M*^2/3^)>2.5) are the most stable, with Toomre Q=1.10+/-0.18, compared to Q=0.53+/-0.22 for galaxies with log(j*/M*^2/3^)<2.5. At a fixed mass, the Hubble Space Telescope morphologies of galaxies with the highest specific angular momentum resemble spiral galaxies, whilst those with low specific angular momentum are morphologically complex and dominated by several bright star-forming regions. This suggests that angular momentum plays a major role in defining the stability of gas discs: at z~1, massive galaxies that have discs with low specific angular momentum are globally unstable, clumpy and turbulent systems. In contrast, galaxies with high specific angular momentum have evolved into stable discs with spiral structure where star formation is a local (rather than global) process.
1118. Galaxies around CenA/M83 galaxy complex
ID:
ivo://CDS.VizieR/J/AJ/133/504
Title:
Galaxies around CenA/M83 galaxy complex
Short Name:
J/AJ/133/504
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Hubble Space Telescope ACS images and color-magnitude diagrams for 24 nearby galaxies in and near the constellation of Centaurus with radial velocities V_LG_<550km/s. Distances are determined based on the luminosities of stars at the tip of the red giant branch that range from 3.0 to 6.5Mpc. The galaxies are concentrated in two spatially separated groups around Cen A (NGC 5128) and M83 (NGC 5236).
1119. Galaxies around M87
ID:
ivo://CDS.VizieR/J/A+A/635/A135
Title:
Galaxies around M87
Short Name:
J/A+A/635/A135
Date:
07 Dec 2021 09:09:23
Publisher:
CDS
Description:
This work considers the Virgo cluster of galaxies, focusing on its structure, kinematics, and morphological landscape. Our principal aim is to estimate the virial mass of the cluster. For this purpose, we present a sample of 1537 galaxies with radial velocities V_LG_<2600km/s situated within a region of 30x20 degrees around M87. About half of the galaxies have distance estimates. We selected 398 galaxies with distances in the (17+/-5)Mpc range. Based on their 1D and 2D number-density profiles and their radial velocity dispersions, we made an estimate for the virial mass of the Virgo cluster. Results. We identify the infall of galaxies towards the Virgo cluster core along the Virgo Southern Extention filament. From a 1D profile of the cluster, we obtain the virial mass estimate of (6.3+/-0.9)x10^14^ solar masses, which is in tight agreement with its mass estimate via the external infall pattern of galaxies. We conclude that the Virgo cluster outskirts between the virial radius and the zero-velocity radius do not contain significant amounts of dark matter beyond the virial radius.
1120. Galaxies around M87 (Kashibadze+, 2020)
ID:
ivo://CDS.VizieR/J/A+A/435/A135
Title:
Galaxies around M87 (Kashibadze+, 2020)
Short Name:
J/A+A/435/A135
Date:
23 Mar 2020 13:32:44
Publisher:
CDS
Description:
Galaxies around M87 with supergalactic coordinates SGL=[87.9, 117.9] degrees, SGB=[-12.4, +7.6] degrees and radial velocities V_LG_<2600km/s. The table contains 1537 galaxies, among them, 738 galaxies have distance estimates: 358 from public databases and 380 distances estimated for the first time in this paper (indicated in the last column as TF or TFb).