- ID:
- ivo://CDS.VizieR/II/179
- Title:
- Southern Spectrophotometric Standards. I + II
- Short Name:
- II/179
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- M. Hamuy, et al. have compiled their observations of secondary and tertiary spectrophotometric standard stars for the southern hemisphere in the wavelength range 3300-7550 Angstroms. The observations were made using the RC spectrographs and CCD cameras on the 1.5m and 4m telescopes at CTIO. The machine-readable files contain monochromatic magnitudes vs. wavelength for 29 stars in ASCII and 31 stars in FITS format.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/500/L17
- Title:
- Spectral flux ratio of SN Ia
- Short Name:
- J/A+A/500/L17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new method to standardize Type Ia supernova (SN Ia) luminosities to ~<0.13mag using flux ratios from a single flux-calibrated spectrum per SN. Using Nearby Supernova Factory spectrophotometry of 58 SNe Ia, we performed an unbiased search for flux ratios that correlate with SN Ia luminosity. After developing the method and selecting the best ratios from a training sample, we verified the results on a separate validation sample and with data from the literature. We identified multiple flux ratios whose correlations with luminosity are stronger than those of light curve shape and color, previously identified spectral feature ratios, or equivalent width measurements. In particular, the flux ratio R(642/443)=Flux(642nm)/Flux(443nm) has a correlation of 0.95 with SN Ia absolute magnitudes. Using this single ratio as a correction factor produces a Hubble diagram with a residual scatter standard deviation of 0.125+/-0.011mag, compared with 0.161+/-0.015mag when fit with the SALT2 light curve shape and color parameters x1 and c. The ratio R(642/443) is an effective correction factor for both extrinsic dust reddening and intrinsic variations such as those of SN 1991T-like and SN 1999aa-like SNe. When combined with broad-band color measurements, spectral flux ratios can standardize SN Ia magnitudes to ~0.12mag. These are the first spectral metrics that give robust improvements over the standard normalization methods based upon light curve shape and color, and they provide among the lowest scatter Hubble diagrams ever published.
- ID:
- ivo://CDS.VizieR/III/219
- Title:
- Spectral Library of Galaxies, Clusters and Stars
- Short Name:
- III/219
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is a compilation of spectra collected along the years at ESO, OHP, CFHT and CASLEO in the near-ultraviolet, optical and near-infrared ranges, complemented by IUE observations. Aiming at population synthesis techniques, average template spectra were built from weighted sums of individual spectra of star clusters taking into account their spectral similarities, ages and metallicities. Morphological types and spectral types, beyond spectral similarities, were considered respectively for galaxy and star template building. Both template and individual spectra are included in the library, which contains spectra for 243 galaxies, 190 clusters and 72 stars, amounting 868 spectra in the various spectral ranges.
- 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.
- ID:
- ivo://CDS.VizieR/III/114
- Title:
- Spectra of Late-Type Standards, 2.0-2.5 Microns
- Short Name:
- III/114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains a collection of K-band spectra for 26 stars with near-solar abundances, ranging in spectral class from F8 to M7 and in luminosity from dwarfs to supergiants. The spectra cover the wavelength region from 4150 to 4950 /cm and generally exhibit a signal to noise ratio above 400. Five stars here are supergiants, 15 are giants, and six are dwarfs. Data included: observation date, starting wavenumber, wavenumber increment, scale factor of relative intensity, and offset of relative intensity.
- ID:
- ivo://CDS.VizieR/VII/141
- Title:
- Spectrophotometric Atlas of Galaxies
- Short Name:
- VII/141
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains 56 spectra: 55 galaxy spectra, and one night sky spectrum, which is included for users wishing to check for low-level spurious features in the galaxy spectra. The file "spectra.dat" contains a summary of the spectra. The user should consult the paper for details of the observations and a discussion of the limitations of the spectrophotometry. The spectra are integrated measurements made with apertures comparable to the diameters of the galaxies. The original spectra have been combined, rebinned to a common wavelength scale, and normalized in flux to unity at a reference wavelength of 555nm. An atmospheric extinction correction has been applied to the data, but otherwise they are not corrected for reddening, redshift, etc. The spectral range covered is 365-710 nm and the resolution is 5-8{AA}. Each spectrum consists in 1726 normalized flux values spaced each 2{AA}, stored as a file in the subdirectory "sp". Tests show that the spectrophotometry is accurate to the few percent level over small wavelength regions, and at the 10% level over the entire wavelength range. Although the data are useful for a variety of applications, the user should be forewarned that they may not be suitable for applications requiring precision colors over a long wavelength baseline (e.g., computation of K-corrections, some spectral synthesis applications).
- ID:
- ivo://CDS.VizieR/VII/102
- Title:
- Spectrophotometric Atlas of Standard Stellar Spectra
- Short Name:
- VII/102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Continuous spectrophotometry has been obtained for 200 objects at a resolution of 10-17 A over the wavelength region 360-1000nm. Kron-Cousins BVRI colors are computed for the spectra and compared with published photoelectric photometry. The (V-R)_C color index is used to group the individual observations to form standard spectra types by stellar class. The standard groups include a solar abundance sequence of most spectral types and luminosity classes, metal-rich and metal weak G-K giant-branch sequences, and horizontal-branch giants. The standard spectra are presented in FITS files, of which a summary is contained in the "list.dat" file.
- ID:
- ivo://CDS.VizieR/J/A+A/383/188
- Title:
- Spectrophotometric atlas of symbiotic stars
- Short Name:
- J/A+A/383/188
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A multi-epoch, absolute-fluxed spectral atlas extending from about 3200 to 9000{AA} is presented for 130 symbiotic stars, including members of the LMC, SMC and Draco dwarf galaxies. The fluxes are accurate to better than 5% as shown by comparison with Tycho and ground-based photometric data. The spectra of 40 reference objects (MK cool giant standards, Mira and Carbon stars, planetary nebulae, white dwarfs, hot sub-dwarfs, Wolf-Rayet stars, classical novae, VV Cep and Herbig Ae/Be objects) are provided to assist the interpretation of symbiotic star spectra. Astrometric positions and counterparts in astrometric catalogues are derived for all program symbiotic stars. The spectra are available in electronic form from the authors.
- ID:
- ivo://CDS.VizieR/III/202
- Title:
- Spectrophotometric Catalogue of Stars
- Short Name:
- III/202
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue contains the absolute energy distribution of the 1147 stars of different spectral type and luminosity classes in the range of 3225-7575A with the step 50A. The observations were made in the Fessenkov Astrophysical Institute (AlmaAta,Kazakstan, height 1450m) during 1968-1986 using spectrum scanner with photo-multiplier tube attached to the 50cm Cassegrain telescope. Standards are Beta Ari, Gamma Ori, Beta Tau, Alpha Leo, Eta UMa, Alpha Lyr, Alpha Aql and Alpha Peg, based on the absolute energy distribution of Vega as given Hayes(1985). The average accuracy of the catalogue data is 3.5%.
- ID:
- ivo://CDS.VizieR/J/A+A/366/68
- Title:
- Spectrophotometric indices from galaxy bulges
- Short Name:
- J/A+A/366/68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have measured Mg_2_, Fe5270 and Fe5335 spectrophotometric indices (LICK system) in the bulge of 89 galaxies, mostly spirals from the Heraudeau sample. The indices are reduced to a null velocity dispersion and normalized to an aperture of 0.2h^-1^kpc. The mean errors are 0.009 mag on Mg_2_, and 0.3{AA} on the iron indices. These measurements almost double the amount of similar data already available on spiral galaxies. Our data confirm the existence of the relation between Mg_2_ and sigma_0_, the central stellar velocity dispersion; and we find an even tighter relation between Mg_2_ and Vmaxrot, the maximum rotational velocity of the galaxy, deduced from HI observations. For the most massive bulges these correlations may be interpreted as a mass-metallicity relation. However, the presence of young stellar populations, traced by the detection of [OIII]{lambda}500.7nm emission, provides a clear evidence that age effects play a role. Since the contribution of the young population is anti-correlated with the mass of the galaxy, it continues the Mg_2_ vs. sigma_0_ relation toward the low sigma_0_ and globally increases its slope. We present also evidence for a new positive correlation between Fe indices and sigma_0_ and for a significant correlation between the line strength indices and the total or disk luminosity. We propose to model the whole sequence of bulges within the following framework: Bulges are composed of a primary population formed prior to the disk during the initial collapse and a secondary population formed along the evolution. The whole family of bulges can be classified in three classes: (A) The bulges dominated by a young population are generally small, have ionized gas, low velocity dispersion and low line strengths. (B) The bulges dominated by the primary population lie along the mass metallicity sequence defined for elliptical galaxies. (C) The bulges where the secondary population is significant are less Mg-overabundant than B-type bulges and deviate from the Mg_2_ vs. sigma_0_ relation of elliptical galaxies. The original data are available in Hypercat: http://www-obs.univ-lyon1.fr/hypercat The tables of measurements and the extracted 1D spectra are also available in the present archive set.
