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61. Abell 168 ultra-diffuse galaxies distribution
ID:
ivo://CDS.VizieR/J/MNRAS/468/703
Title:
Abell 168 ultra-diffuse galaxies distribution
Short Name:
J/MNRAS/468/703
Date:
21 Oct 2021
Publisher:
CDS
Description:
Taking advantage of the Sloan Digital Sky Survey Stripe82 data, we have explored the spatial distribution of ultra-diffuse galaxies (UDGs) within an area of 8x8Mpc^2^ centred around the galaxy cluster Abell 168 (z=0.045). This intermediate massive cluster ({sigma}=550km/s) is surrounded by a complex large-scale structure. Our work confirms the presence of UDGs in the cluster and in the large-scale structure that surrounds it, and it is the first detection of UDGs outside clusters. Approximately 50 per cent of the UDGs analysed in the selected area inhabit the cluster region (~11+/-5 per cent in the core and ~39+/-9 per cent in the outskirts), whereas the remaining UDGs are found outside the main cluster structure (~50+/-11 per cent). The colours and the spatial distribution of the UDGs within this large-scale structure are more similar to dwarf galaxies than to L* galaxies, suggesting that most UDGs could be bona fide dwarf galaxies.
62. Abell 2052 VLT/MUSE datacubes
ID:
ivo://CDS.VizieR/J/A+A/612/A19
Title:
Abell 2052 VLT/MUSE datacubes
Short Name:
J/A+A/612/A19
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report observations of the radio galaxy 3C317 (at z=0.0345) located at the center of the Abell cluster A2052, obtained with the VLT/MUSE integral field spectrograph. The Chandra images of this cluster show cavities in the X-ray emitting gas, which were produced by the expansion of the radio lobes inflated by the active galactic nucleus (AGN). Our exquisite MUSE data show with unprecedented detail the complex network of line emitting filaments enshrouding the northern X-ray cavity. We do not detect any emission lines from the southern cavity, with a luminosity asymmetry between the two regions higher than ~75. The emission lines produced by the warm phase of the interstellar medium (WIM) enable us to obtain unique information on the properties of the emitting gas. We find dense gas (up to 270cm^-3^) that makes up part of a global quasi spherical outflow that is driven by the radio source, and obtain a direct estimate of the expansion velocity of the cavities (265km/s). The emission lines diagnostic rules out ionization from the AGN or from star-forming regions, suggesting instead ionization from slow shocks or from cosmic rays. The striking asymmetric line emission observed between the two cavities contrasts with the less pronounced differences between the north and south sides in the hot gas; this represents a significant new ingredient for our understanding of the process of the exchange of energy between the relativistic plasma and the external medium. We conclude that the expanding radio lobes displace the hot tenuous phase of the interstellar medium (ISM), but also impact the colder and denser ISM phases. These results show the effects of the AGN on its host and the importance of radio mode feedback.
63. Ab initio EOS for hydrogen-helium mixtures
ID:
ivo://CDS.VizieR/J/ApJ/774/148
Title:
Ab initio EOS for hydrogen-helium mixtures
Short Name:
J/ApJ/774/148
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using density functional molecular dynamics simulations, we determine the equation of state (EOS) for hydrogen-helium mixtures spanning density-temperature conditions typical of giant-planet interiors, ~0.2-9g/cm3 and 1000-80000K for a typical helium mass fraction of 0.245. In addition to computing internal energy and pressure, we determine the entropy using an ab initio thermodynamic integration technique. A comprehensive EOS table with 391 density-temperature points is constructed and the results are presented in the form of a two-dimensional free energy fit for interpolation. Deviations between our ab initio EOS and the semi-analytical EOS model by Saumon and Chabrier (1992PhRvA..46.2084S, 1995ApJS...99..713S) are analyzed in detail, and we use the results for initial revision of the inferred thermal state of giant planets with known values for mass and radius. Changes are most pronounced for planets in the Jupiter mass range and below. We present a revision to the mass-radius relationship that makes the hottest exoplanets increase in radius by ~0.2 Jupiter radii at fixed entropy and for masses greater than ~0.5 Jupiter mass. This change is large enough to have possible implications for some discrepant "inflated giant exoplanets."
64. Ab initio EOS for water-hydrogen mixtures
ID:
ivo://CDS.VizieR/J/ApJ/806/228
Title:
Ab initio EOS for water-hydrogen mixtures
Short Name:
J/ApJ/806/228
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from ab initio simulations of liquid water-hydrogen mixtures in the range from 2 to 70GPa and from 1000 to 6000K, covering conditions in the interiors of ice giant planets and parts of the outer envelope of gas giant planets. In addition to computing the pressure and the internal energy, we derive the Gibbs free energy by performing a thermodynamic integration. For all conditions under consideration, our simulations predict hydrogen and water to mix in all proportions. The thermodynamic behavior of the mixture can be well described with an ideal mixing approximation. We suggest that a substantial fraction of water and hydrogen in giant planets may occur in homogeneously mixed form rather than in separate layers. The extent of mixing depends on the planet's interior dynamics and its conditions of formation, in particular on how much hydrogen was present when icy planetesimals were delivered. Based on our results, we do not predict water-hydrogen mixtures to phase separate during any stage of the evolution of giant planets. We also show that the hydrogen content of an exoplanet is much higher if the mixed interior is assumed.
65. Absolute Calibration of Stellar Spectrophotometry
ID:
ivo://CDS.VizieR/II/85
Title:
Absolute Calibration of Stellar Spectrophotometry
Short Name:
II/85
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog contains the absolute fluxes for 16 stars published in Tables 1 and 2 of Johnson (1980). The absolute calibrations were accomplished by combining the 13-color photometry calibrations of Johnson and Mitchell (1975) with spectra obtained with a Michelson spectrophotometer and covering the wavelength range 4000 to 10300 Angstroms (Johnson 1977). The agreement between the absolute calibration and another recent one based upon data for alpha Lyr and 109 Vir by Tug et al. (1977) is shown (Johnson 1980) to be quite good. The catalog includes star name, cross identifications to the numbering systems of the Bright Star Catalogue and The Henry Draper Catalogue and arrays of fluxes having the same number of elements for each of the 16 stars.
66. Absolute flux distribution of BD +17 4708
ID:
ivo://CDS.VizieR/J/AJ/128/3053
Title:
Absolute flux distribution of BD +17 4708
Short Name:
J/AJ/128/3053
Date:
21 Oct 2021
Publisher:
CDS
Description:
Secondary flux standards are established by measuring their brightness relative to primary standard stars. The Hubble Space Telescope (HST) primary standards are the three pure-hydrogen white dwarf (WD) flux standards that determine the sensitivity calibration for the Space Telescope Imaging Spectrograph. STIS observations have defined the flux of the Sloan Digital Sky Survey (SDSS, http://www.sdss.org) standard BD+17 4708 from 0.17 to 1.0{mu}m with an uncertainty of less than 0.5% relative to the HST primary standards, as verified by two independent sets of photometry.
67. Absolute fluxes and distances of PN
ID:
ivo://CDS.VizieR/J/A+AS/94/399
Title:
Absolute fluxes and distances of PN
Short Name:
J/A+AS/94/399
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a complete list of averaged recalibrated absolute H{beta} fluxes, global (where possible) relative He II {lambda} 4686 fluxes, 5-GHz radio flux densities, and H{alpha}/H{beta} interstellar extinction constants for 778 Galactic planetary nebulae. The catalog provides much of the fundamental data required to generate Zanstra temperatures. When data with the lowest errors are selected, the optical and radio/optical extinctions show a peculiar correlation, with the radio values slightly high at low extinction and notably low at high extinction. The data are used, along with the best estimates of angular diameters, to calculate Shklovsky distances according to the Daub scheme on the scale used earlier by Cahn and Kaler (1971ApJS...22..319C). Use of this distance scale shows approximate equality of the death rates of optically thick and optically thin planetary nebulae. The method gives the correct distances to the Magellanic Clouds.
68. Absolute magnitude of Globular Cluster
ID:
ivo://CDS.VizieR/J/MNRAS/365/1357
Title:
Absolute magnitude of Globular Cluster
Short Name:
J/MNRAS/365/1357
Date:
21 Oct 2021
Publisher:
CDS
Description:
We test whether the peak absolute magnitude MV(TO) of the Globular Cluster Luminosity Function (GCLF) can be used for reliable extragalactic distance determination. Starting with the luminosity function of the Galactic Globular Clusters listed in Harris (Cat. <VII/202>) catalogue, we determine MV(TO) either using current calibrations of the absolute magnitude MV(RR) of RR Lyrae stars as a function of the cluster metal content [Fe/H] and adopting selected cluster samples.
69. Absolute magnitudes for late-type dwarfs
ID:
ivo://CDS.VizieR/J/AN/326/321
Title:
Absolute magnitudes for late-type dwarfs
Short Name:
J/AN/326/321
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new formula for absolute magnitude determination for late-type dwarf stars as a function of (g-r) and (r-i) for Sloan photometry (as defined by Abazajian et al., 2003AJ....126.2081A). The absolute magnitudes estimated by this approach are brighter than those estimated by colour-magnitude diagrams, and they reduce the luminosity function rather close to the luminosity function of Hipparcos.
70. Absolute magnitudes of cataclysmic variables
ID:
ivo://CDS.VizieR/J/other/NewA/12.446
Title:
Absolute magnitudes of cataclysmic variables
Short Name:
J/other/NewA/12.
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using reliable trigonometric measurements, we find that the absolute magnitude of cataclysmic variables depends on the orbital period and de-reddened (J-H)_0_ and (H-Ks)_0_ colours of 2MASS (Two Micron All Sky Survey) photometric system. The calibration equation covers the ranges 0.032d<P_orb_<=0.454d, -0.08<(J-H)_0_<=1.54, -0.03<(H-Ks)_0_<=0.56 and 2.0<M_J_<11.7; It is based on trigonometric parallaxes with relative errors of ({sigma}{pi}/{pi})<=0.4. By using the period-luminosity-colours (PLCs) relation, we estimated the distances of cataclysmic variables with orbital periods and 2MASS observations and compared them with distances found from other methods. We suggest that the PLCs relation can be a useful statistical tool to estimate the distances of cataclysmic variables.

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