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771. Fe XII UV line intensity ratios
ID:
ivo://CDS.VizieR/J/A+A/370/1071
Title:
Fe XII UV line intensity ratios
Short Name:
J/A+A/370/1071
Date:
21 Oct 2021
Publisher:
CDS
Description:
A new set of radiative and electron collisional data for Fe XII was presented in two earlier papers. In the present work, we derive level populations and theoretical line intensities for a range of plasma densities and temperatures. Observations of Fe XII lines obtained with the Solar EUV Rocket Telescope and Spectrograph are analysed both as a check on the quality of the new atomic data and to determine the electron density in active regions and the quiet Sun. The discrepancy between the electron density values determined from Fe XII line intensity ratios and those obtained from other ions is investigated.
772. F-G-K stars activity indicators
ID:
ivo://CDS.VizieR/J/A+A/658/A57
Title:
F-G-K stars activity indicators
Short Name:
J/A+A/658/A57
Date:
22 Feb 2022
Publisher:
CDS
Description:
Different relationships between the H{alpha} and CaII chromospheric emissions have been reported in solar-type stars. In particular, the time-series of emissions in these two lines are clearly anti-correlated for a few percent of the stars, contrary to what is observed on the Sun. Our objective is to characterise these relationships in more detail using complementary criteria, and to constrain the properties of filaments and plages that are necessary to explain the observations. We analysed the average level and variability of the H{alpha} and CaII emission for 441 F-G-K stars, paying particular attention to their (anti-)correlations on both short and long timescales. We also computed synthetic H{alpha} and CaII time-series for different assumptions of plage and filament properties and compared them with the observations. We were not able to find plage properties that, alone, are sufficient to reproduce the observations at all timescales simultaneously, even when allowing different H{alpha} and CaII emission relationships for different stars. We also specified the complex and surprising relationship between the average activity levels of both indexes, in particular for low-activity stars. We conclude that plages alone are unlikely to explain the observed variety of relationships between CaII and H{alpha} emission, and that the presence of other phenomena like filaments may help to reconcile the models with observations.
773. FGK stars magnetic activity in LAMOST-Kepler field
ID:
ivo://CDS.VizieR/J/ApJS/247/9
Title:
FGK stars magnetic activity in LAMOST-Kepler field
Short Name:
J/ApJS/247/9
Date:
21 Oct 2021
Publisher:
CDS
Description:
Monitoring chromospheric and photospheric indexes of magnetic activity can provide valuable information, especially the interaction between different parts of the atmosphere and their response to magnetic fields. We extract chromospheric indexes, S and R_HK_^+^, for 59816 stars from LAMOST spectra in the LAMOST-Kepler program, and photospheric index, Reff, for 5575 stars from Kepler light curves. The log Reff shows positive correlation with logR_HK_^+^. We estimate the power-law indexes between Reff and R_HK_^+^ for F-, G-, and K-type stars, respectively. We also confirm the dependence of both chromospheric and photospheric activity on stellar rotation. Ca ii H and K emissions and photospheric variations generally decrease with increasing rotation periods for stars with rotation periods exceeding a few days. The power-law indexes in exponential decay regimes show different characteristics in the two activity-rotation relations. The updated largest sample including the activity proxies and reported rotation periods provides more information to understand the magnetic activity for cool stars.
774. 2FGL J0846.0+2820 opt. counterpart follow-up
ID:
ivo://CDS.VizieR/J/ApJ/851/31
Title:
2FGL J0846.0+2820 opt. counterpart follow-up
Short Name:
J/ApJ/851/31
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present optical photometric and spectroscopic observations of the likely stellar counterpart to the unassociated Fermi Large Area Telescope (LAT) {gamma}-ray source 2FGL J0846.0+2820, selected for study based on positional coincidences of optical variables with unassociated LAT sources. Using optical spectroscopy from the SOAR telescope, we have identified a late-G giant in an eccentric (e=0.06) 8.133-day orbit with an invisible primary. Modeling the spectroscopy and photometry together led us to infer a heavy neutron star primary of ~2M_{sun}_ and a partially stripped giant secondary of ~0.8M_{sun}_. H{alpha} emission is observed in some of the spectra, perhaps consistent with the presence of a faint accretion disk. We find that the {gamma}-ray flux of 2FGL J0846.0+2820 dropped substantially in mid-2009, accompanied by an increased variation in the optical brightness, and since then, it has not been detected by Fermi. The long period and giant secondary are reminiscent of the {gamma}-ray bright binary 1FGL J1417.7-4407, which hosts a millisecond pulsar (MSP) apparently in the final stages of the pulsar recycling process. The discovery of 2FGL J0846.0+2820 suggests the identification of a new subclass of MSP binaries that are the likely progenitors of typical field MSPs.
775. FG Sagittae: new observations
ID:
ivo://CDS.VizieR/J/PAZh/29/858
Title:
FG Sagittae: new observations
Short Name:
J/PAZh/29/858
Date:
21 Oct 2021
Publisher:
CDS
Description:
In 1999-2002 the BVRI photometric and spectroscopic observations of FG Sge were made. The star has been in a new R CrB photometric phase since 1992.
776. Final Merged Log of IUE Observations
ID:
ivo://CDS.VizieR/VI/110
Title:
Final Merged Log of IUE Observations
Short Name:
VI/110
Date:
21 Oct 2021
Publisher:
CDS
Description:
The log contains a summary of all IUE Newly Extracted Spectra (INES), which resulted from a post-processing effort at Vilspa. It was constructed by using verified data from the IUE Final Archive Master Catalogue. The observations cover the whole life of the satellite, from March 1978 to September 1996.
777. Finding list for multiplet tables of NSRDS-NBS 3
ID:
ivo://CDS.VizieR/VI/29A
Title:
Finding list for multiplet tables of NSRDS-NBS 3
Short Name:
VI/29A
Date:
21 Oct 2021
Publisher:
CDS
Description:
The primary references for stellar line identifications in the optical and ultraviolet spectral regions have been "A Multiplet Table of Astrophysical Interest" (RMT, Moore 1945) and "An Ultraviolet Multiplet Table" (UMT, Moore 1950, 1952, 1962). Dr. Charlotte Moore Sitterly has, over the last two decades, undertaken a revision of certain multiplet tables based on data derived from analyses of optical spectra. The present finding list has been prepared from the data published in the first ten sections of these revised tables: -------------------------------------------------- Section Year Elements -------------------------------------------------- 1 1965 Si II, Si III, Si IV 2 1967 Si I 3 1970 C I, C II, C III, C IV, C V, C VI 4 1970 N IV, N V, N VI, N VII 5 1975 N I, N II, N III 6 1972 H I, D I, T I 7 1976 O I 8 1979 O VI, O VII, O VIII 9 1980 O V 10 1983 O IV -------------------------------------------------- An earlier finding list containing Sections 1-7 only was published by Adelman, Adelman and Fischel (1977) (Catalogue VI/11). We have revised the format and added information to the earlier list, and have appended Sections 8-10 to produce the present version. We intend to incorporate future sections to produce new comprehensive lists as the sections are published and can be computerized. This document describes the machine version of the finding list as it is currently being distributed from the Astronomical Data Center. It is intended to enable users to read and process the data without problems and guesswork, and to interpret the various codes used in the list without recourse to the original publications. However, for additional details concerning the multiplet tables and analyses of the optical spectra, the source publications and their associated references should be consulted.
778. FIR spectra of AGNs from Herschel
ID:
ivo://CDS.VizieR/J/ApJS/226/19
Title:
FIR spectra of AGNs from Herschel
Short Name:
J/ApJS/226/19
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a coherent database of spectroscopic observations of far-IR fine-structure lines from the Herschel/Photoconductor Array Camera and Spectrometer (PACS) archive for a sample of 170 local active galactic nuclei (AGNs), plus a comparison sample of 20 starburst galaxies and 43 dwarf galaxies. Published Spitzer/IRS and Herschel/SPIRE line fluxes are included to extend our database to the full 10-600{mu}m spectral range. The observations are compared to a set of Cloudy photoionization models to estimate the above physical quantities through different diagnostic diagrams. We confirm the presence of a stratification of gas density in the emission regions of the galaxies, which increases with the ionization potential of the emission lines. The new [OIV]_25.9um_/[OIII]_88um_ versus [NeIII]_15.6um_/[NeII]_12.8um_ diagram is proposed as the best diagnostic to separate (1) AGN activity from any kind of star formation and (2) low-metallicity dwarf galaxies from starburst galaxies. Current stellar atmosphere models fail to reproduce the observed [OIV]_25.9um_/[OIII]_88um_ ratios, which are much higher when compared to the predicted values. Finally, the ([NeIII]_15.6um_+[NeII]_12.8um_)/([SIV]_10.5um_+[SIII]_18.7um_) ratio is proposed as a promising metallicity tracer to be used in obscured objects, where optical lines fail to accurately measure the metallicity. The diagnostic power of mid- to far-infrared spectroscopy shown here for local galaxies will be of crucial importance to study galaxy evolution during the dust-obscured phase at the peak of the star formation and black hole accretion activity (1<z<4). This study will be addressed by future deep spectroscopic surveys with present and forthcoming facilities such as the James Webb Space Telescope, the Atacama Large Millimeter/submillimeter Array, and the Space Infrared telescope for Cosmology and Astrophysics.
779. FIRST-2MASS dust-reddened QSO spectra
ID:
ivo://CDS.VizieR/J/ApJ/757/51
Title:
FIRST-2MASS dust-reddened QSO spectra
Short Name:
J/ApJ/757/51
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a sample of 120 dust-reddened quasars identified by matching radio sources detected at 1.4GHz in the Faint Images of the Radio Sky at Twenty Centimeters survey (FIRST) with the near-infrared Two Micron All Sky Survey catalog (2MASS) and color-selecting red sources. Optical and/or near-infrared spectroscopy provide broad wavelength sampling of their spectral energy distributions that we use to determine their reddening, characterized by E(B-V). We demonstrate that the reddening in these quasars is best described by Small-Magellanic-Cloud-like dust. This sample spans a wide range in redshift and reddening (0.1<~z<~3, 0.1<~E(B-V)<~1.5), which we use to investigate the possible correlation of luminosity with reddening. At every redshift, dust-reddened quasars are intrinsically the most luminous quasars. We interpret this result in the context of merger-driven quasar/galaxy co-evolution where these reddened quasars are revealing an emergent phase during which the heavily obscured quasar is shedding its cocoon of dust prior to becoming a "normal" blue quasar. When correcting for extinction, we find that, depending on how the parent population is defined, these red quasars make up <~15%-20% of the luminous quasar population. We estimate, based on the fraction of objects in this phase, that its duration is 15%-20% as long as the unobscured, blue quasar phase.
780. First release of the MaNGA Stellar Library (MaStar)
ID:
ivo://CDS.VizieR/J/ApJ/883/175
Title:
First release of the MaNGA Stellar Library (MaStar)
Short Name:
J/ApJ/883/175
Date:
29 Nov 2021 07:46:33
Publisher:
CDS
Description:
We present the first release of the MaNGA Stellar Library (MaStar), which is a large, well-calibrated, high-quality empirical library covering the wavelength range 3622-10354{AA} at a resolving power of R~1800. The spectra were obtained using the same instrument as used by the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) project, by piggybacking on the Sloan Digital Sky Survey (SDSS-IV)/Apache Point Observatory Galaxy Evolution Experiment 2-N (APOGEE-2N) observations. Compared to previous empirical libraries, the MaStar library will have a higher number of stars and a more comprehensive stellar-parameter coverage, especially of cool dwarfs, low-metallicity stars, and stars with different [{alpha}/Fe], achieved by a sophisticated target-selection strategy that takes advantage of stellar-parameter catalogs from the literature. This empirical library will provide a new basis for stellar-population synthesis and is particularly well suited for stellar-population analysis of MaNGA galaxies. The first version of the library contains 8646 high-quality per-visit spectra for 3321 unique stars. Compared to photometry, the relative flux calibration of the library is accurate to 3.9% in g-r, 2.7% in r-i, and 2.2% in i-z. The data are released as part of SDSS Data Release 15. We expect the final release of the library to contain more than 10000 stars.

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