- ID:
- ivo://CDS.VizieR/J/A+A/585/A64
- Title:
- New atmospheric parameters of MILES cool stars
- Short Name:
- J/A+A/585/A64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The full spectrum fitting of stellar spectra against a library of empirical spectra is a well-established approach to measure the atmospheric parameters of FGK stars with a high internal consistency. Extending it towards cooler stars still remains a challenge. We address this question by improving the MILES interpolator (Prugniel et al., 2011, Cat. J/A+A/531/A165; hereafter PVK) in the low effective temperature regime (Teff<4800K). We measure the biases of the determined parameters with respect to our updated compilation of parameters. After correcting some systematic effects, we compute a new interpolator that we finally use to redetermine the atmospheric parameters homogeneously and assess the biases. Based on an updated literature compilation, we determine Teff in a more accurate and unbiased manner compared to those determined with the original interpolator. The validity range is extended downwards to about Teff=2900K compared to 3500K previously. The measured parameters are restricted to the current sub sample of MILES, and we have shown that they are generally more reliable than those presented in PVK. But the small discontinuity between the PVK and new measurements is significant, in particular for Teff, and should be corrected if one needs to join the two series.
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- ID:
- ivo://CDS.VizieR/J/A+A/525/A74
- Title:
- 540-690nm Solar Atlas
- Short Name:
- J/A+A/525/A74
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Astronomical research dealing with accurate radial velocity measurements need reliable astronomical standards to calibrate the spectrographs and to assess possible systematics. Stellar radial velocity standards offer a reference at the level of a few hundred m/s and are not adequate for most present needs. We aim to show that sunlight reflected by asteroids is a fairly accessible way to record a high-resolution solar spectrum from the whole disk, which can therefore be used as a radial velocity standard and can improve the uncertainties of solar line positions.
- ID:
- ivo://CDS.VizieR/J/other/ApSS/353.347
- Title:
- 398-710nm Sun spectral atlases
- Short Name:
- J/other/ApSS/353
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work, we present digital and graphical atlases of spectra of both the solar disk-center and of the limb near the Solar poles using data taken at the UTS-IAP & RIAAM (the University of Tabriz Siderostat, telescope and spectrograph jointly developed with the Institut d'Astrophysique de Paris and Research Institute for Astronomy and Astrophysics of Maragha). High resolution and high signal-to-noise ratio (SNR) CCD-slit spectra of the sun for 2 different parts of the disk, namely for {mu}=1.0 (solar center) & for {mu}=0.3 (solar limb) are provided and discussed. While there are several spectral atlases of the solar disk-center, this is the first spectral atlas ever produced for the solar limb at this spectral range. The resolution of the spectra is about R~70000 ({Delta}{lambda}~0.09{AA})} with the signal-to-noise ratio (SNR) of 400-600. The full atlas covers the 3980 to 7100{AA} spectral regions and contains 44 pages with three partial spectra of the solar spectrum put on each page to make it compact. The difference spectrum of the normalized each page to make it compact. The difference spectrum of the normalized solar disk-center and the solar limb is also included in the graphic presentation of the atlas to show the difference of line profiles, including far wings. The identification of most of the significant solar lines are included in the graphic presentation of the atlas. Telluric lines are producing a definite signature on the difference spectra which is easy to notice.
- ID:
- ivo://CDS.VizieR/J/A+AS/105/305
- Title:
- OB stars observed with high dispersion by IUE
- Short Name:
- J/A+AS/105/305
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- An atlas on microfiche is described containing nearly 7000 high-dispersion spectra of OB stars obtained during the first 10 years with the IUE satellite. The data set is nearly complete for the selected time interval. The plotted wavelength range is from 1160 to 1890 A at the original IUE sampling intervals. The atlas is available by request.
- ID:
- ivo://CDS.VizieR/J/ApJS/145/199
- Title:
- Optical spectroscopic atlas of low-redshift AGN
- Short Name:
- J/ApJS/145/199
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a spectral atlas of the H{beta} region for 215 type 1 AGNs (luminous Seyfert 1/radio galaxy nuclei and low-z quasars) up to z~0.8. Line profiles and measures were derived from the database of intermediate resolution spectra (R>~1000) with average continuum level S/N ratio ~30. Parameters including rest frame equivalent width and FWHM are provided for the FeII_opt_ blend at {lambda}4570, H{beta}, HeII {lambda}4686, and the [OIII] {lambda}{lambda}4959, 5007 emission lines. We extract clean broad component H{beta} profiles and provide wavelength measurements at 0, 1/4, 1/2, 3/4, and 0.9 peak intensity levels in order to permit a quantitative definition of the H{beta} broad component for statistical studies. We also discuss sources of uncertainty, selection effects, and biases in our sample. The data are especially important for tests of the eigenvector 1 parameter space occupation and correlation. We show that the I Zw 1 template FeII_opt_ spectrum reproduces well the observed FeII_opt_ emission for a wide range of line width and strength. A detailed analysis of the data within the eigenvector 1 context is deferred to a companion paper.
- ID:
- ivo://CDS.VizieR/J/A+A/592/A103
- Title:
- Planetary nebulae monochromatic images atlas
- Short Name:
- J/A+A/592/A103
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an atlas of more than one hundred original images of planetary nebulae (PNe). These images were taken in a narrow-band filter centred on the nebular emission of the [NII] during several observing campaigns using two moderate-aperture telescopes, at the Complejo Astronomico El Leoncito (CASLEO), and the Estacion Astrofisica de Bosque Alegre (EABA), both in Argentina. The data provided by this atlas represent one of the most extensive image surveys of PNe in [NII]. We compare the new images with those available in the literature, and briefly describe all cases in which our [NII] images reveal new and interesting structures.
- ID:
- ivo://CDS.VizieR/VIII/31
- Title:
- Revised source list for the Rees 38-MHz survey
- Short Name:
- VIII/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a revised machine-readable source list for the Rees 38-MHz (or '8C') survey with improved positions and no redundancy. The Rees 38-MHz survey covers an area of about 1 sr north of declination +60 degrees. The angular resolution is 4.5 x 4.5cosec(Dec) arcmin**2 and the limiting flux density over much of the survey area is about 1 Jy. Both of these figures are an improvement by nearly an order of magnitude on previous surveys at this frequency. Users of these data should consult and cite the original survey paper by Rees as primary reference (1990MNRAS.244..233R) with the present publication (1995MNRAS.274..447H) as a supplementary revision. The recommended style of reference is thus : "The revised Rees 38-MHz survey (Rees 1990, catalogue revised Hales et. al 1995)." Note that for interest the source list includes data on some sources at declinations lower than +60 degrees, but that the right ascension coverage is not complete below +60 degrees.
- ID:
- ivo://CDS.VizieR/J/A+A/508/309
- Title:
- Spectral atlas of HD 50138
- Short Name:
- J/A+A/508/309
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The observed spectral variation of HD50138 led different authors in the literature to classify it in a very large range of spectral types and luminosity classes (from B5 to A0 and III to Ia) and at different evolutionary stages, as either an HAeBe star or a classical Be. Based on new high-resolution optical spectroscopic data from 1999 and 2007, we perform a detailed spectral description, presenting the variations seen and discussing their possible origin. We tentatively suggest that a new shell phase could have taken place prior to our observations in 2007. We derive the interstellar extinction to HD50138 by taking into account the influences of the circumstellar matter in the form of dust and an ionized disk. We find a color excess value of E(B-V)=0.08mag. Based on photometric data from the literature and the new Hipparcos distance, we obtain a revised set of parameters for HD50138, suggesting that it is a B6-7 III-V star. A discussion about the different evolutionary scenarios is also provided.
- ID:
- ivo://CDS.VizieR/J/AJ/140/1758
- Title:
- Spectral atlas of peculiar stars
- Short Name:
- J/AJ/140/1758
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an Echelle+CCD, high S/N, high resolution (R=20000) spectroscopic atlas of 108 well-known objects representative of the most common types of peculiar and variable stars. The wavelength interval extends from 4600 to 9400{AA}, and includes the RAVE, Gaia and HERMES wavelength ranges. Multi-epoch spectra are provided for the majority of observed stars. A total of 425 spectra of peculiar stars are presented, which have been collected during 56 observing nights between November 1998 and August 2002. The spectra are given in FITS format and heliocentric wavelengths, with accurate subtraction of both the sky background and the scattered light. Auxiliary material useful for custom applications (telluric dividers, spectro-photometric stars, flat-field tracings) is also provided. The atlas aims to provide a homogeneous database of the spectral appearance of stellar peculiarities, a tool useful both for classification purposes and inter-comparison studies. It could also serve the planning for and training of automated classification algorithms designed for RAVE, Gaia, HERMES and other large scale spectral surveys. The spectrum of XX Oph is discussed in some detail as an example of the content of the present atlas.
- ID:
- ivo://CDS.VizieR/J/A+A/608/A122
- Title:
- Spectra of 28 intermediate redshift quasars
- Short Name:
- J/A+A/608/A122
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Broad emission lines in quasars enable us to "resolve" structure and kinematics of the broad-line emitting region (BLR) thought to involve an accretion disk feeding a supermassive black hole. Interpretation of broad line measures within the 4DE1 formalism simplifies the apparent confusion among such data by contrasting and unifying properties of so-called high and low accreting Population A and B sources. H-beta serves as an estimator of black hole mass, Eddington ratio and source rest frame; the latter being a valuable input for CIV 1549 studies which allow us to isolate the blueshifted wind component. Optical and HST-UV spectra yield H-beta and CIV 1549 spectra for low-luminosity sources while VLT-ISAAC and FORS and TNG-LRS provide spectra for high-luminosity sources. New high-S/N data for CIV in high-luminosity quasars are presented here for comparison with the other previously published data. Comparison of H-beta and CIV 1549 profile widths/shifts indicates that much of the emission from the two lines arise in regions with different structure and kinematics. Covering a wide range of luminosity and redshift shows evidence for a correlation between CIV 1549 blueshift and source Eddington ratio, with a weaker trend with source luminosity (similar amplitude outflows are seen over four of the five dex luminosity ranges in our combined samples). At low luminosity (z<0.7) only Population A sources show evidence for a significant outflow while at high luminosity the outflow signature begins to appear in Population B quasars as well.
