- ID:
- ivo://CDS.VizieR/J/ApJ/599/886
- Title:
- Emission lines of radio-loud AGN
- Short Name:
- J/ApJ/599/886
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the completion of a survey of radio-loud active galactic nuclei (AGNs) begun in an earlier paper (Eracleous & Halpern, 1994ApJS...90....1E) with the main goal of finding and studying broad, double-peaked Balmer lines. We present H{alpha} spectra of 13 more broad-lined objects, including three with double-peaked H{alpha} profiles. The final sample includes 106 radio-loud AGNs. In our final census 20% of objects have H{alpha} lines with double peaks or twin shoulders (the "double-peaked emitters"), and of these 60% (the disklike emitters) can be fitted quite well with a model attributing the emission to a circular, relativistic, Keplerian disk. In four objects where broad H{beta} and Mg II lines have been observed, we compare the profiles with models of photoionized accretion disks and find them to be in reasonable agreement.
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Search Results
- ID:
- ivo://CDS.VizieR/III/203
- Title:
- Emission Lines of the Planetary Nebulae
- Short Name:
- III/203
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The relative intensities of emission lines in the spectra of 32 planetary nebulae in the 3700-7300{AA} region are presented. The spectral observations have been carried out using slit spectrograph with three-cascades image-tube, attached to 70-cm reflector (Alma-Ata). The spectral region is 3700-8500{AA}. The dispersion in the range of 12-200{AA}/mm. The spectral resolution is 0.8-13{AA} in dependence on the dispersion. The errors are less than 10% for the bright lines, 10-15% for the moderate lines and 25-50% for the faintest lines. All measured line intensities were normalised to I(Hbeta)=100.
- ID:
- ivo://CDS.VizieR/J/ApJ/832/118
- Title:
- Emission-line spectroscopy in NGC 891
- Short Name:
- J/ApJ/832/118
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The observed scale heights of extraplanar diffuse ionized gas (eDIG) layers exceed their thermal scale heights by a factor of a few in the Milky Way and other nearby edge-on disk galaxies. Here, we test a dynamical equilibrium model of the eDIG layer in NGC 891, where we ask whether the thermal, turbulent, magnetic field, and cosmic-ray pressure gradients are sufficient to support the layer. In optical emission-line spectroscopy from the SparsePak integral field unit on the WIYN 3.5m telescope, the H{alpha} emission in position-velocity space suggests that the eDIG is found in a ring between galactocentric radii of R_min_<=R<=8kpc, where R_min_>=2kpc. We find that the thermal ({sigma}_th_=11km/s) and turbulent ({sigma}_turb_=25km/s) velocity dispersions are insufficient to satisfy the hydrostatic equilibrium equation given an exponential electron scale height of h_z_=1.0kpc. Using a literature analysis of radio continuum observations from the CHANG-ES survey, we demonstrate that the magnetic field and cosmic-ray pressure gradients are sufficient to stably support the gas at R>=8kpc if the cosmic rays are sufficiently coupled to the system ({gamma}_cr_=1.45). Thus, a stable dynamical equilibrium model is viable only if the eDIG is found in a thin ring around R=8kpc, and nonequilibrium models such as a galactic fountain flow are of interest for further study.
- ID:
- ivo://CDS.VizieR/J/MNRAS/326/959
- Title:
- Empirical calibration of the near-IR Ca triplet
- Short Name:
- J/MNRAS/326/959
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- File table contains details of the new near-IR stellar library observed to calibrate the Ca II triplet. It includes the indices CaT*, CaT and PaT measured over the final spectra as well as their corresponding errors. The Henry Draper Catalogue number, other names (mainly HR and BD numbers), coordinates, spectral type, luminosity class, apparent magnitude and atmospheric parameters (as derived in Paper II; Cenarro et al., 2001MNRAS.326..981C) are also given.
- ID:
- ivo://CDS.VizieR/J/MNRAS/420/1684
- Title:
- End of red sequence galaxies in Galaxy Zoo
- Short Name:
- J/MNRAS/420/1684
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a study of local post-starburst galaxies (PSGs) using the photometric and spectroscopic observations from the Sloan Digital Sky Survey and the results from the Galaxy Zoo project. We find that the majority of our local PSG population have neither early- nor late-type morphologies but occupy a well-defined space within the colour-stellar mass diagram, most notably, the low-mass end of the 'green valley' below the transition mass thought to be the mass division between low-mass star-forming galaxies and high-mass passively evolving bulge-dominated galaxies.
- ID:
- ivo://CDS.VizieR/J/AJ/135/1311
- Title:
- Environments of moderate redshift radio galaxies
- Short Name:
- J/AJ/135/1311
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the local universe, high-power radio galaxies live in lower-density environments than low-luminosity radio galaxies. If this trend continued to higher redshifts, powerful radio galaxies would serve as efficient probes of moderate redshift groups and poor clusters. Photometric studies of radio galaxies at 0.3<~z<~0.5 suggest that the radio luminosity-environment correlation disappears at moderate redshifts, though this could be the result of foreground/background contamination affecting the photometric measures of environment. We have obtained multi-object spectroscopy in the fields of 14 lower luminosity (L_1.4GHz_<4x10^24^W/Hz) and higher luminosity (L_1.4GHz_>1.2x10^25^W/Hz) radio galaxies at z~0.3 to spectroscopically investigate the link between the environment and the radio luminosity of radio galaxies at moderate redshifts. Our results support the photometric analyses; there does not appear to be a correlation between the luminosity of a radio galaxy and its environment at moderate redshifts. Hence, radio galaxies are not efficient signposts for group environments at moderate redshifts.
- ID:
- ivo://CDS.VizieR/J/MNRAS/447/2404
- Title:
- Equivalent width of 21 RR Lyrae stars
- Short Name:
- J/MNRAS/447/2404
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have analysed a sample of 18 RR Lyrae stars (17 fundamental-mode - RRab - and one first overtone - RRc) and three Population II Cepheids (two BL Her stars and one W Vir star), for which high-resolution (R>=30000), high signal-to-noise (S/N>=30) spectra were obtained with either SARG at the Telescopio Nazionale Galileo (La Palma, Spain) or UVES at the ESO Very Large Telescope (Paranal, Chile). Archival data were also analyzed for a few stars, sampling >~3 phases for each star. We obtained atmospheric parameters (T_eff_, logg, v_t_, and [M/H]) and abundances of several iron-peak and {alpha}-elements (Fe, Cr, Ni, Mg, Ca, Si, and Ti) for different pulsational phases, obtaining <[{alpha}/Fe]>=+0.31+/-0.19dex over the entire sample covering -2.2<[Fe/H]<-1.1dex. We find that silicon is indeed extremely sensitive to the phase, as reported by previous authors, and cannot be reliably determined. Apart from this, metallicities and abundance ratios are consistently determined, regardless of the phase, within 0.10-0.15 dex, although caution should be used in the range 0<~{phi}<~0.15. Our results agree with literature determinations for both variable and non-variable field stars, obtained with very different methods, including low and high-resolution spectroscopy. W Vir and BL Her stars, at least in the sampled phases, appear indistinguishable from RRab from the spectroscopic analysis point of view. Our large sample, covering all pulsation phases, confirms that chemical abundances can be obtained for RR Lyrae with the classical EW-based technique and static model atmospheres, even rather close to the shock phases.
- ID:
- ivo://CDS.VizieR/J/MNRAS/448/42
- Title:
- Equivalent widths and atomic data for GCs
- Short Name:
- J/MNRAS/448/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Detailed chemical abundances for five stars in two Galactic globular clusters, NGC 5466 and NGC 5024, are presented from high-resolution optical (from the Hobby-Eberley Telescope) and infrared spectra (from the SDSS-III APOGEE survey). We find [Fe/H]=-1.97+/-0.13 dex for NGC 5466, and [Fe/H]=-2.06+/-0.13 dex for NGC 5024, and the typical abundance pattern for globular clusters for the remaining elements, e.g. both show evidence for mixing in their light element abundance ratios (C, N), and asymptotic giant branch contributions in their heavy element abundances (Y, Ba, and Eu). These clusters were selected to examine chemical trends that may correlate them with the Sgr dwarf galaxy remnant, but at these low metallicities no obvious differences from the Galactic abundance pattern are found. Regardless, we compare our results from the optical and infrared analyses to find that oxygen and silicon abundances determined from the infrared spectral lines are in better agreement with the other {alpha}-element ratios and with smaller random errors.
- ID:
- ivo://CDS.VizieR/J/A+A/377/123
- Title:
- Equivalent widths of 6 binaries
- Short Name:
- J/A+A/377/123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We performed a careful differential abundance analysis of individual components of six main sequence binaries with separations of a few hundreds of AU. To reduce analysis concerns, we selected systems with almost equal mass components. We were able to derive differential abundances of several elements with errors down to 0.01dex in the best cases. We found that in four systems the two components have the same chemical composition, within these very severe limits. However, clear differences were found for the two remaining systems (HD 219542 and HD 200466), in both cases the primaries being more Fe-rich than the secondaries, by 0.091+/-0.009 and 0.053+/-0.024dex respectively. Similar differences were found for most of the elements considered in our analysis; however, we found no appreciable difference for volatile elements and a trend for increasing abundance differences with increasing condensation temperature for individual elements, a result similar to that found for some single stars with planets by Smith et al. (2001AJ....121.3207S). Finally, we note that HD 219542A has a Li-abundance comparable to those of Li-rich stars in old open clusters, while no Li is detected in the slightly cooler HD 219542B. We suggest that the primaries of these two systems have accreted rocky planets or the inner dust-rich part of a protoplanetary disk, likely due to gravitational perturbation caused by the presence of the companion.
- ID:
- ivo://CDS.VizieR/J/A+A/555/A25
- Title:
- Equivalent widths of DIBs
- Short Name:
- J/A+A/555/A25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Stellar spectroscopic surveys may bring useful statistical information on the links between diffuse interstellar bands (DIBs) and the interstellar environment. DIB databases can also be used as a complementary tool for locating interstellar (IS) clouds. Our goal is to develop fully automated methods of DIB measurements to be applied to extensive data from stellar surveys. We present a method that is appropriate for early-type nearby stars, along with its application to high-resolution spectra of ~130 targets recorded with the ESO FEROS spectrograph and comparisons with other determinations. Using a DIB average profile deduced from the most reddened stars, we performed an automated fitting of a combination of a smooth stellar continuum, the DIB profile, and, when necessary, a synthetic telluric transmission.
