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81. Absolute reflectance & new calibration site of the Moon
ID:
ivo://CDS.VizieR/J/AJ/155/213
Title:
Absolute reflectance & new calibration site of the Moon
Short Name:
J/AJ/155/213
Date:
21 Oct 2021
Publisher:
CDS
Description:
How bright the Moon is forms a simple but fundamental and important question. Although numerous efforts have been made to answer this question such as use of sophisticated electro-optical measurements and suggestions for calibration sites, the answer is still debated. An in situ measurement with a calibration panel on the surface of the Moon is crucial for obtaining the accurate absolute reflectance and resolving the debate. China's Chang'E-3 (CE-3) "Yutu" rover accomplished this type of measurement using the Visible-Near Infrared Spectrometer (VNIS). The measurements of the VNIS, which were at large emission and phase angles, complement existing measurements for the range of photometric geometry. The in situ reflectance shows that the CE-3 landing site is very dark with an average reflectance of 3.86% in the visible bands. The results are compared with recent mission instruments: the Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC), the Spectral Profiler (SP) on board the SELENE, the Moon Mineralogy Mapper (M^3^) on board the Chandrayaan-1, and the Chang'E-1 Interference Imaging Spectrometer (IIM). The differences in the measurements of these instruments are very large and indicate inherent differences in their absolute calibration. The M^3^ and IIM measurements are smaller than LROC WAC and SP, and the VNIS measurement falls between these two pairs. When using the Moon as a radiance source for the on-orbit calibration of spacecraft instruments, one should be cautious about the data. We propose that the CE-3 landing site, a young and homogeneous surface, should serve as the new calibration site.
82. Absolute Refletivity of Jupiter and Saturn
ID:
ivo://CDS.VizieR/J/A+A/607/A72
Title:
Absolute Refletivity of Jupiter and Saturn
Short Name:
J/A+A/607/A72
Date:
21 Oct 2021
Publisher:
CDS
Description:
We provide measurements of the absolute reflectivity of Jupiter and Saturn along their central meridians in filters covering a wide range of visible and near-infrared wavelengths (from 0.38 to 1.7um) that are not often presented in the literature. We also give measurements of the geometric albedo of both planets and discuss the limb-darkening behavior and temporal variability of their reflectivity values for a period of four years (2012-2016). This work is based on observations with the PlanetCam-UPV/EHU instrument at the 1.23m and 2.2m telescopes in Calar Alto Observatory (Spain). The instrument simultaneously observes in two channels: visible (VIS; 0.38-1.0um) and short-wave infrared (SWIR; 1.0-1.7um). We obtained high-resolution observations via the lucky-imaging method. We show that our calibration is consistent with previous independent determinations of reflectivity values of these planets and, for future reference, provide new data extended in the wavelength range and in the time. Our results have an uncertainty in absolute calibration of 10-20%. We show that under the hypothesis of constant geometric albedo, we are able to detect absolute reflectivity changes related to planetary temporal evolution of about 5-10%.
83. Absolute R mag of brightest cluster galaxies
ID:
ivo://CDS.VizieR/J/ApJ/425/418
Title:
Absolute R mag of brightest cluster galaxies
Short Name:
J/ApJ/425/418
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have measured the velocity of the Local Group with respect to an inertial frame defined by the 119 Abell and Abell, Corwin, & Olowin (ACO, Cat. <VII/110A>) clusters contained within 15000km/s. The observations consist of a full-sky peculiar velocity survey with an effective depth ranging from 8000 to 11000km/s, depending on how the observations are weighted with redshift. This is the deepest peculiar velocity survey yet conducted. Clusters are selected by heliocentric redshift, and the sample is volume-limited. We use the Hoessel (1980ApJ...241..493H) relationship between the metric luminosities of the brightest clusters galaxies (BCGs) and the slope of their brightness profiles as the distance indicator. The Cousins R-band luminosity within a metric radius of 10h^-1^kpc yields a typical distance error of 16% for a single BCG.
84. Absolute spectrum of the Sun and Vega for 0.2-30um
ID:
ivo://CDS.VizieR/J/AJ/135/2245
Title:
Absolute spectrum of the Sun and Vega for 0.2-30um
Short Name:
J/AJ/135/2245
Date:
21 Oct 2021
Publisher:
CDS
Description:
We determine an absolute calibration for the Multiband Imaging Photometer for Spitzer 24um band and recommend adjustments to the published calibrations for Two Micron All Sky Survey (2MASS), Infrared Array Camera (IRAC), and IRAS photometry to put them on the same scale. We show that consistent results are obtained by basing the calibration on either an average A0V star spectral energy distribution (SED), or by using the absolutely calibrated SED of the Sun in comparison with solar-type stellar photometry (the solar analog method).
85. Absolute UV magnitudes of type Ia SNe
ID:
ivo://CDS.VizieR/J/ApJ/721/1608
Title:
Absolute UV magnitudes of type Ia SNe
Short Name:
J/ApJ/721/1608
Date:
21 Oct 2021
Publisher:
CDS
Description:
We examine the absolute magnitudes and light-curve shapes of 14 nearby (redshift z=0.004-0.027) Type Ia supernovae (SNe Ia) observed in the ultraviolet (UV) with the Swift Ultraviolet/Optical Telescope. Colors and absolute magnitudes are calculated using both a standard Milky Way extinction law and one for the Large Magellanic Cloud that has been modified by circumstellar scattering. We find very different behavior in the near-UV filters (uvw1_rc_ covering ~2600-3300{AA} after removing optical light, and u~3000-4000{AA}) compared to a mid-UV filter (uvm2~2000-2400{AA}).
86. Absorption coefficient of polystyrene
ID:
ivo://CDS.VizieR/J/A+A/517/A60
Title:
Absorption coefficient of polystyrene
Short Name:
J/A+A/517/A60
Date:
21 Oct 2021
Publisher:
CDS
Description:
The surfaces of airless bodies in the Solar System are continuously altered by the bombardment of micrometeoroids and irradiation by solar wind, flares, and cosmic particles. Major effects of this process - space weathering - are darkening and "reddening" of the spectra of surface materials, as well as a "degrading" of absorption features. We studied the changes induced by energetic ion irradiation in the ultraviolet-visual-near-infrared (UV-Vis-NIR) (0.2-0.98um) reflectance spectra of targets selected to mimic the surfaces of airless bodies in the inner Solar System. Our chosen targets are olivine pellets, pure or covered by an organic polymer (polystyrene), which is transparent before irradiation. Polystyrene is used as a template for organic matter of low volatility that can be present on asteroidal surfaces. Moreover we measured the changes induced by ion irradiation in the absorption coefficient of the polymer. The purpose was to have a tool to better compare laboratory with observed spectra and distinguish between planetary objects with pure silicate surfaces and those whose surface is covered by organic matter exposed to cosmic ion bombardment.
87. Absorption & emission lines and RVel for vA 351
ID:
ivo://CDS.VizieR/J/AJ/161/285
Title:
Absorption & emission lines and RVel for vA 351
Short Name:
J/AJ/161/285
Date:
08 Mar 2022
Publisher:
CDS
Description:
We extend results first announced by Franz et al., that identified vA351=H346 in the Hyades as a multiple star system containing a white dwarf. With Hubble Space Telescope Fine Guidance Sensor fringe tracking and scanning, and more recent speckle observations, all spanning 20.7years, we establish a parallax, relative orbit, and mass fraction for two components, with a period, P=2.70yr and total mass 2.1M{sun}. With ground-based radial velocities from the McDonald Observatory Otto Struve 2.1m Telescope Sandiford Spectrograph, and Center for Astrophysics Digital Speedometers, spanning 37 years, we find that component B consists of BC, two M-dwarf stars orbiting with a very short period (P_BC_=0.749days), having a mass ratio M_C_/M_B_=0.95. We confirm that the total mass of the system can only be reconciled with the distance and component photometry by including a fainter, higher-mass component. The quadruple system consists of three M dwarfs (A, B, C) and one white dwarf (D). We determine individual M-dwarf masses M_A_=0.53{+/-}0.10M{sun}, M_B_=0.43{+/-}0.04M{sun}, and M_C_=0.41{+/-}0.04M{sun}. The white dwarf mass, 0.54{+/-}0.04M{sun}, comes from cooling models, an assumed Hyades age of 670Myr, and consistency with all previous and derived astrometric, photometric, and radial velocity results. Velocities from H{alpha} and HeI emission lines confirm the BC period derived from absorption lines, with similar (HeI) and higher (H{alpha}) velocity amplitudes. We ascribe the larger H{alpha} amplitude to emission from a region each component shadows from the other, depending on the line of sight.
88. Absorption features in SDSS. I. MgII abs. doublets
ID:
ivo://CDS.VizieR/J/ApJS/235/11
Title:
Absorption features in SDSS. I. MgII abs. doublets
Short Name:
J/ApJS/235/11
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the SDSS spectra of quasars included in the DR7Q or DR12Q catalogs, we search for MgII{lambda}{lambda}2796,2803 narrow absorption doublets in the spectra data around MgII{lambda}2798 emission lines. We obtain 17316 MgII doublets, within the redshift range of 0.3299<=z_abs_<=2.5663. We find that a velocity offset of {upsilon}_r_<6000km/s is a safe boundary to constrain the vast majority of associated Mg ii systems, although we find some doublets at {upsilon}_r_>6000km/s. If associated Mg ii absorbers are defined by {upsilon}_r_<6000km/s, ~33.3% of the absorbers are supposed to be contaminants of intervening systems. Removing the 33.3% contaminants, ~4.5% of the quasars present at least one associated MgII system with W_r_^{lambda}2796^>=0.2{AA}. The fraction of associated MgII systems with high-velocity outflows correlates with the average luminosities of their central quasars, indicating a relationship between outflows and the quasar feedback power. The {upsilon}_r_ distribution of the outflow MgII absorbers is peaked at 1023km/s, which is smaller than the corresponding value of the outflow CIV absorbers. The redshift number density evolution of absorbers (dn/dz) limited by {upsilon}_r_{>}-3000km/s differs from that of absorbers constrained by {upsilon}_r_>2000km/s. Absorbers limited by {upsilon}_r_>2000km/s and higher values exhibit profiles similar to dn/dz. In addition, the dn/dz is smaller when absorbers are constrained with larger {upsilon}_r_. The distributions of equivalent widths, and the ratio of W_r_^{lambda}2796^/W_r_^{lambda}2803^, are the same for associated and intervening systems, and independent of quasar luminosity.
89. Absorption in multiphase circumgalactic medium
ID:
ivo://CDS.VizieR/J/MNRAS/445/2061
Title:
Absorption in multiphase circumgalactic medium
Short Name:
J/MNRAS/445/2061
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper presents an absorption-line study of the multiphase circumgalactic medium (CGM) based on observations of Ly{alpha}, CII, CIV, SiII, SiIII, and SiIV absorption transitions in the vicinities of 195 galaxies at redshift z<0.176. The galaxy sample is established based on a cross-comparison between public galaxy and quasi-stellar object (QSO) survey data and is characterized by a median redshift of <z>=0.041, a median projected distance of <d>=362kpc to the sightline of the background QSO, and a median stellar mass of log(M_star_/M_{sun}_)=9.7+/-1.1. Comparing the absorber features identified in the QSO spectra with known galaxy properties has led to strong constraints for the CGM absorption properties at z<~0.176. First, abundant hydrogen gas is observed out to d~500kpc, well beyond the dark matter halo radius R_h_ of individual galaxies, with a mean covering fraction of ~60 percent. In contrast, no heavy elements are detected at d>~0.7R_h_ from either low-mass dwarfs or high-mass galaxies. The lack of detected heavy elements in low- and high-ionization states suggests that either there exists a chemical enrichment edge at d~0.7R_h_ or gaseous clumps giving rise to the observed absorption lines cannot survive at these large distances. Considering all galaxies at d>R_h_ leads to a strict upper limit for the covering fraction of heavy elements of ~3% (at a 95% confidence level) over d=(1-9)R_h_. At d<R_h_, differential covering fraction between low- and high-ionization gas is observed, suggesting that the CGM becomes progressively more ionized from d<0.3R_h_ to larger distances. Comparing CGM absorption observations at low and high redshifts shows that at a fixed fraction of R_h_ the CGM exhibits stronger mean absorption at z=2.2 than at z~0, and that the distinction is most pronounced in low-ionization species traced by CII and SiII absorption lines. We discuss possible pseudo-evolution of the CGM as a result of misrepresentation of halo radius, and present a brief discussion on the implications of these findings.
90. Absorption lines in 21 Lyn A-type star
ID:
ivo://CDS.VizieR/J/ApJS/239/19
Title:
Absorption lines in 21 Lyn A-type star
Short Name:
J/ApJS/239/19
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalog of absorption lines in the z', Y, and J bands that we identified in 21 Lyn, a slowly rotating A0.5V star. We detected 155 absorption features in the high-resolution (0.90-1.35um, R=28000) spectrum obtained with the WINERED spectrograph after the telluric absorption was carefully removed using a spectrum of a B-type star as a telluric standard. With a visual comparison with synthetic spectra, we compiled a catalog of 219 atomic lines for the 155 features, some of which are composed of multiple fine structure lines. The high-quality WINERED spectrum enabled us to detect a large number of weak lines down to ~1% in depth, which are identified for an A-type star for the first time. The catalog includes the lines of H, C, N, O, Mg, Al, Si, S, Ca, Fe, and Sr. These new lines are expected to be useful for spectral classification and chemical abundance analyses, while the line catalog is useful for observers who plan to use A-type stars as telluric standards because it is necessary to distinguish between stellar lines and telluric absorption lines in high-resolution spectra. ASCII versions of the spectra are available in the online version of the journal.

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