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951. Analysis of K2 LCs for members of USco & {rho} Oph
ID:
ivo://CDS.VizieR/J/AJ/155/196
Title:
Analysis of K2 LCs for members of USco & {rho} Oph
Short Name:
J/AJ/155/196
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of K2 light curves (LCs) for candidate members of the young Upper Sco (USco) association (~8 Myr) and the neighboring {rho} Oph embedded cluster (~1 Myr). We establish ~1300 stars as probable members, ~80% of which are periodic. The phased LCs have a variety of shapes which can be attributed to physical causes ranging from stellar pulsation and stellar rotation to disk-related phenomena. We identify and discuss a number of observed behaviors. The periods are ~0.2-30 days with a peak near 2 days and the rapid period end nearing breakup velocity. M stars in the young USco region rotate systematically faster than GK stars, a pattern also present in K2 data for the older Pleiades and Praesepe systems. At higher masses (types FGK), the well-defined period-color relationship for slowly rotating stars seen in the Pleiades and Praesepe systems is not yet present in USco. Circumstellar disks are present predominantly among the more slowly rotating M stars in USco, with few disks in the subday rotators. However, M dwarfs with disks rotate faster on average than FGK systems with disks. For four of these disked M dwarfs, we provide direct evidence for disk locking based on the K2 LC morphologies. Our preliminary analysis shows a relatively mass-independent spin-up by a factor of ~3.5 between USco and the Pleiades, then mass-dependent spin-down between Pleiades and Praesepe.
952. Analysis of the B3IV star HD 43317
ID:
ivo://CDS.VizieR/J/A+A/542/A55
Title:
Analysis of the B3IV star HD 43317
Short Name:
J/A+A/542/A55
Date:
21 Oct 2021
Publisher:
CDS
Description:
OB stars are important building blocks of the Universe, but we have only a limited sample of them well understood enough from an asteroseismological point of view to provide feedback on the current evolutionary models. Our study adds one special case to this sample, with more observational constraints than for most of these stars. Our goal is to analyse and interpret the pulsational behaviour of the B3 IV star HD 43317 using the CoRoT light curve along with the ground-based spectroscopy gathered by the Harps instrument. This way we continue our efforts to map the Beta Cep and SPB instability strips. We used different techniques to reveal the abundances and fundamental stellar parameters from the newly-obtained high-resolution spectra. We used various time-series analysis tools to explore the nature of variations present in the light curve. We calculated the moments and used the pixel-by-pixel method to look for line profile variations in the high- resolution spectra. We find that HD 43317 is a single fast rotator (v_rot_~50%v_crit_) and hybrid SPB/Beta Cep-type pulsator with Solar metal abundances. We interpret the variations in photometry and spectroscopy as a result of rotational modulation connected to surface inhomogeneities, combined with the presence of both g and p mode pulsations. We detect a series of ten consecutive frequencies with an almost constant period spacing of 6339s as well as a second shorter sequence consisting of seven frequencies with a spacing of 6380s. The dominant frequencies fall in the regime of gravito- inertial modes.
953. Analysis of the Ly{alpha} forest at z=0-5. V.
ID:
ivo://CDS.VizieR/J/ApJ/571/665
Title:
Analysis of the Ly{alpha} forest at z=0-5. V.
Short Name:
J/ApJ/571/665
Date:
21 Oct 2021
Publisher:
CDS
Description:
In Paper III (Bechtlod et al., 2002, Cat. <J/ApJS/140/143>) of our series, "A Uniform Analysis of the Ly{alpha} Forest at z=0-5", we presented a set of 270 quasar spectra from the archives of the Faint Object Spectrograph (FOS) on the Hubble Space Telescope (HST). A total of 151 of these spectra, yielding 906 lines, are suitable for using the proximity effect signature to measure J({nu}_0_), the mean intensity of the hydrogen-ionizing background radiation field, at low redshift.
954. Analysis of the NIR spectra of neighboring L dwarfs
ID:
ivo://CDS.VizieR/J/AJ/155/34
Title:
Analysis of the NIR spectra of neighboring L dwarfs
Short Name:
J/AJ/155/34
Date:
21 Oct 2021
Publisher:
CDS
Description:
Discrepancies between competing optical and near-infrared (NIR) spectral typing systems for L dwarfs have motivated us to search for a classification scheme that ties the optical and NIR schemes together, and addresses complexities in the spectral morphology. We use new and extant optical and NIR spectra to compile a sample of 171 L dwarfs, including 27 low-gravity {beta} and {gamma} objects, with spectral coverage from 0.6-2.4 {mu}m. We present 155 new low-resolution NIR spectra and 19 new optical spectra. We utilize a method for analyzing NIR spectra that partially removes the broad-band spectral slope and reveals similarities in the absorption features between objects of the same optical spectral type. Using the optical spectra as an anchor, we generate near-infrared spectral average templates for L0-L8, L0-L4{gamma}, and L0-L1{beta} type dwarfs. These templates reveal that NIR spectral morphologies are correlated with the optical types. They also show the range of spectral morphologies spanned by each spectral type. We compare low-gravity and field-gravity templates to provide recommendations on the minimum required observations for credibly classifying low-gravity spectra using low-resolution NIR data. We use the templates to evaluate the existing NIR spectral standards and propose new ones where appropriate. Finally, we build on the work of Kirkpatrick et al. to provide a spectral typing method that is tied to the optical and can be used when only H or K band data are available. The methods we present here provide resolutions to several long-standing issues with classifying L dwarf spectra and could also be the foundation for a spectral classification scheme for cloudy exoplanets.
955. Analysis of the RC catalog sample.
ID:
ivo://CDS.VizieR/VIII/86
Title:
Analysis of the RC catalog sample.
Short Name:
VIII/86
Date:
21 Oct 2021
Publisher:
CDS
Description:
of paper I: 432 radio sources of the RC catalog produced in 1980-1985 at RATAN-600 radio telescope based on a deep survey of a sky strip centered on the declination of the SS433 source are identified in the region overlapping with FIRST and SDSS surveys (about 132{deg}^2^ large). The NVSS catalog was used as the reference catalog for refining the coordinates of the radio sources. The morphology is found for about 75% of the objects of the sample and the ratio of single, double and multicomponent radio sources is computed based on FIRST radio maps. The 74, 365, 1400, and 4850MHz data of the VLSS, TXS, NVSS, FIRST, and GB6 catalogs are used to analyze the shape of the spectra.
956. Analysis of the spectrum of {eta} Car
ID:
ivo://CDS.VizieR/J/ApJS/181/473
Title:
Analysis of the spectrum of {eta} Car
Short Name:
J/ApJS/181/473
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of the visible through near-infrared spectrum of Eta Carinae ({eta} Car) and its ejecta obtained during the "{eta} Car Campaign with the Ultraviolet and Visual Echelle Spectrograph (UVES) at the ESO Very Large Telescope (VLT)." This is a part of larger effort to present a complete {eta} Car spectrum, and extends the previously presented analyses with the Hubble Space Telescope/Space Telescope Imaging Spectrograph (HST/STIS) in the UV (1240-3159{AA}) to 10430{AA}. The spectrum in the mid- and near-UV is characterized by the ejecta absorption. At longer wavelengths, stellar wind features from the central source and narrow-emission lines from the Weigelt condensations dominate the spectrum. However, narrow absorption lines from the circumstellar shells are present. This paper provides a description of the spectrum between 3060 and 10430{AA}, including line identifications of the ejecta absorption spectrum, the emission spectrum from the Weigelt condensations and the P Cygni stellar wind features. The high spectral resolving power of VLT/UVES enables equivalent width measurements of atomic and molecular absorption lines for elements with no transitions at the shorter wavelengths. However, the ground-based seeing and contributions of nebular-scattered radiation prevent direct comparison of measured equivalent widths in the VLT/UVES and HST/STIS spectra. Fortunately, HST/STIS and VLT/UVES have a small overlap in wavelength coverage which allows us to compare and adjust for the difference in scattered radiation entering the instruments' apertures. This paper provides a complete online VLT/UVES spectrum with line identifications and a spectral comparison between HST/STIS and VLT/UVES between 3060 and 3160{AA}.
957. An analysis of the Ap binary HD 81009
ID:
ivo://CDS.VizieR/J/A+A/361/991
Title:
An analysis of the Ap binary HD 81009
Short Name:
J/A+A/361/991
Date:
21 Oct 2021
Publisher:
CDS
Description:
File table2.dat contains the 74 new measured radial velocities of the primary component of the SB2 HD 81009.
958. An astrometric catalogue of radio stars
ID:
ivo://CDS.VizieR/V/67
Title:
An astrometric catalogue of radio stars
Short Name:
V/67
Date:
21 Oct 2021
Publisher:
CDS
Description:
Astrometric data in the optical and radio spectral ranges have been assembled for some 200 radio stars which are considered promising objects for linkage of optical and radio frames. Astrophysical data have been added to support observational programmes and data analysis. The full catalogue, in its original form as the file "catalog.ori", contains explanations, followed by the data for each star organised as paragraphs (blocks of lines separated by a blank line). Each paragraph representing a radio star in this catalog consists of 17 categories of stellar parameters; each category may contain zero, one, or more records. The positions, proper motions and parallaxes in the optical and radio domains are assigned categories 1 to 7; categories 8 to 13 deal with photometrical and spectroscopical parameters, duplicity and variability descriptions; and categories 14 to 17 contain references to finding charts and radio maps, as well as remarks about observation priorities. A detailed description of these categories are present at the beginning of the "catalog.ori" file.
959. An atlas of FUV spectra of 31 Cyg
ID:
ivo://CDS.VizieR/J/ApJS/211/27
Title:
An atlas of FUV spectra of 31 Cyg
Short Name:
J/ApJS/211/27
Date:
21 Oct 2021
Publisher:
CDS
Description:
The {zeta} Aurigae system 31 Cygni (K4 Ib + B4 V) was observed by the FUSE satellite during total eclipse and at three phases during chromospheric eclipse. We present the coadded, calibrated spectra and atlases with line identifications. During total eclipse, emission from high ionization states (e.g., Fe III and Cr III) shows asymmetric profiles redshifted from the systemic velocity, while emission from lower ionization states (e.g., Fe II and O I) appears more symmetric and is centered closer to the systemic velocity. Absorption from neutral and singly ionized elements is detected during chromospheric eclipse. Late in chromospheric eclipse, absorption from the K star wind is detected at a terminal velocity of ~80km/s. These atlases will be useful for interpreting the far-UV spectra of other {zeta} Aur systems, as the observed FUSE spectra of 32 Cyg, KQ Pup, and VV Cep during chromospheric eclipse resemble that of 31 Cyg.
960. An Atlas of Near Infrared Stellar Spectra
ID:
ivo://CDS.VizieR/III/153
Title:
An Atlas of Near Infrared Stellar Spectra
Short Name:
III/153
Date:
21 Oct 2021
Publisher:
CDS
Description:
The atlas represents a collection of spectra in the wavelength range 2.00 to 2.45 micrometers having a resolution of approximately 0.02 micrometers. The sample of 73 stars includes a supergiant, giants, dwarfs, and subdwarfs with a chemical abundance range of about -2 to +0.5 dex.

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