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- 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.
- 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.
- 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.
- 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.
- 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.
- ID:
- ivo://CDS.VizieR/J/AJ/159/187
- Title:
- First RVs with the EXPRES spectrograph: 51Peg
- Short Name:
- J/AJ/159/187
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The EXtreme-PREcision Spectrograph (EXPRES) is an environmentally stabilized, fiber-fed, R=137500, optical spectrograph. It was recently commissioned at the 4.3m Lowell Discovery Telescope near Flagstaff, Arizona. The spectrograph was designed with a target radial-velocity (RV) precision of 30cm/s. In addition to instrumental innovations, the EXPRES pipeline, presented here, is the first on-sky, optical, fiber-fed spectrograph to employ many novel techniques-including an "extended flat" fiber used for wavelength-dependent quantum efficiency characterization of the CCD, a flat-relative optimal extraction algorithm, chromatic barycentric corrections, chromatic calibration offsets, and an ultra-precise laser frequency comb for wavelength calibration. We describe the reduction, calibration, and RV analysis pipeline used for EXPRES and present an example of our current sub-meter-per-second RV measurement precision, which reaches a formal, single-measurement error of 0.3m/s for an observation with a per-pixel signal-to-noise ratio of 250. These velocities yield an orbital solution on the known exoplanet host 51Peg that matches literature values with a residual rms of 0.895m/s.
- ID:
- ivo://CDS.VizieR/J/AJ/151/142
- Title:
- Five years of blazar observations with VERITAS
- Short Name:
- J/AJ/151/142
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Between the beginning of its full-scale scientific operations in 2007 and 2012, the VERITAS Cherenkov telescope array observed more than 130 blazars; of these, 26 were detected as very-high-energy (VHE; E>100 GeV) {gamma}-ray sources. In this work, we present the analysis results of a sample of 114 undetected objects. The observations constitute a total live-time of ~570 hr. The sample includes several unidentified Fermi-Large Area Telescope (LAT) sources (located at high Galactic latitude) as well as all the sources from the second Fermi-LAT catalog (Nolan et al. 2012, J/ApJS/199/31) that are contained within the field of view of the VERITAS observations. We have also performed optical spectroscopy measurements in order to estimate the redshift of some of these blazars that do not have spectroscopic distance estimates. We present new optical spectra from the Kast instrument on the Shane telescope at the Lick observatory for 18 blazars included in this work, which allowed for the successful measurement or constraint on the redshift of four of them. For each of the blazars included in our sample, we provide the flux upper limit in the VERITAS energy band. We also study the properties of the significance distributions and we present the result of a stacked analysis of the data set, which shows a 4{sigma} excess.
- ID:
- ivo://CDS.VizieR/J/A+A/580/A64
- Title:
- FK Com spectra in H{alpha}
- Short Name:
- J/A+A/580/A64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the connection between the chromospheric and photospheric behaviour of the active late-type star FK Comae. We use spot temperature modelling, light curve inversion based on narrow- and wide-band photometric measurements, Halpha observations from 1997-2010, and Doppler maps from 2004-2010 to compare the behaviour of chromospheric and photospheric features. Investigating low-resolution H{alpha} spectra we find that the changes in the chromosphere seem to happen mainly on a time scale longer than a few hours, but shorter variations were also observed. According to the Halpha measurements prominences are often found in the chromosphere that reach to more than a stellar radius and are stable for weeks, and which seem to be often, but not every time connected with dark photospheric spots. The rotational modulation of the H{alpha} emission seems to typically be anticorrelated with the light curve, but we did not find convincing evidence of a clear connection in the long-term trends of the Halpha emission and the brightness of the star. In addition, FK Com seems to be in an unusually quiet state in 2009-2010 with very little chromospheric activity and low spot contrast, that might indicate the long-term decrease of activity.
- ID:
- ivo://CDS.VizieR/J/A+A/607/A44
- Title:
- FLAMES observations of NGC6535
- Short Name:
- J/A+A/607/A44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To understand globular clusters (GCs) we need to comprehend how their formation process was able to produce their abundance distribution of light elements. In particular, we need to figure out which stars imprinted the peculiar chemical signature of GCs. One of the best way is to study the light-element anti-correlations in a large sample of GCs, analysed homogeneously. As part of our spectroscopic survey of GCs with FLAMES, we present here the results of our study of about 30 red giant member stars in the low-mass, low-metallicity Milky Way cluster NGC 6535. We measured its metallicity (finding [Fe/H]=-1.95, rms=0.04dex in our homogeneous scale) and other elements, in particular we concentrate here on O and Na abundances. These elements define the normal Na-O anti-correlation of classical GCs, making NGC 6535 perhaps the lowest mass cluster with confirmed presence of multiple populations. We updated the census of Galactic and extragalactic GCs for which a statement on the presence or absence of multiple populations can be made on the basis of high-resolution spectroscopy preferentially, or photometry and low-resolution spectroscopy otherwise, discussing the importance of mass and age of the clusters.
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