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2661. Spectroscopy of Ultraluminous IR galaxies
ID:
ivo://CDS.VizieR/J/AJ/132/2596
Title:
Spectroscopy of Ultraluminous IR galaxies
Short Name:
J/AJ/132/2596
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the types of nuclear environments that produce OH megamasers (OHMs) with a study of the optical spectra of 40 OHM host galaxies and a control sample of 30 non-masing (ultra)luminous infrared galaxies ([U]LIRGs). The optical spectrophotometry provides spatially resolved spectra of multiple nuclei in a few of these merging systems. Of the 40 OHMs classified, 33% are starbursts, 42% are LINERs, and 25% are Seyfert 2 galaxies; the classification of the non-masing control sample is similar.
2662. Spectroscopy of UMa II and Coma Ber
ID:
ivo://CDS.VizieR/J/ApJ/708/560
Title:
Spectroscopy of UMa II and Coma Ber
Short Name:
J/ApJ/708/560
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present spectra of six metal-poor stars in two of the ultra-faint dwarf galaxies orbiting the Milky Way (MW), Ursa Major II, and Coma Berenices obtained with the Keck/High Resolution Echelle Spectrometer (HIRES). These observations include the first high-resolution spectroscopic observations of extremely metal-poor ([Fe/H]<-3.0) stars not belonging to the MW halo field star population. We obtain abundance measurements and upper limits for 26 elements between carbon and europium. The entire sample of stars spans a range of -3.2<[Fe/H]<-2.3, and we confirm that each galaxy contains a large intrinsic spread of Fe abundances. A comparison with MW halo stars of similar metallicities reveals substantial agreement between the abundance patterns of the ultra-faint dwarf galaxies and the MW halo for the light, {alpha}, and iron-peak elements (C to Zn). The abundances of neutron-capture elements (Sr to Eu) in the ultra-faint dwarf galaxies are extremely low, consistent with the most metal-poor halo stars, but not with the typical halo abundance pattern at [Fe/H]>~-3.0. Not only are our results broadly consistent with a galaxy formation model that predicts that massive dwarf galaxies are the source of the metal-rich component ([Fe/H]>-2.5) of the MW halo, but they also suggest that the faintest known dwarfs may be the primary contributors to the metal-poor end of the MW halo metallicity distribution.
2663. Spectroscopy of very low mass objects
ID:
ivo://CDS.VizieR/J/A+A/540/A85
Title:
Spectroscopy of very low mass objects
Short Name:
J/A+A/540/A85
Date:
21 Oct 2021
Publisher:
CDS
Description:
With a uniform VLT SINFONI data set of nine targets, we have developed an empirical grid of J, H, K spectra of the atmospheres of objects estimated to have very low substellar masses of ~5-20M_Jup_ and young ages ranging from ~1-50Myr. Most of the targets are companions, objects which are especially valuable for comparison with atmosphere and evolutionary models, as they present rare cases in which the age is accurately known from the primary. Based on the youth of the sample, all objects are expected to have low surface gravity, and this study investigates the critical early phases of the evolution of substellar objects. The spectra are compared with grids of five different theoretical atmosphere models. ************************************************************************** * * * Sorry, but the author(s) never supplied the tabular material * * announced in the paper * * * **************************************************************************
2664. Spectroscopy of 12 [WC] planetary nebulae
ID:
ivo://CDS.VizieR/J/A+A/538/A54
Title:
Spectroscopy of 12 [WC] planetary nebulae
Short Name:
J/A+A/538/A54
Date:
21 Oct 2021
Publisher:
CDS
Description:
Planetary nebulae (PNe) around Wolf-Rayet [WR] central stars ([WR]PNe) constitute a particular photoionized nebula class that represents about 10% of the PNe with classified central stars. We analyse deep high-resolution spectrophotometric data of 12 [WR] PNe. This sample of [WR]PNe represents the most extensive analysed so far, at such high spectral resolution. We aim to select the optimal physical conditions in the nebulae to be used in ionic abundance calculations that will be presented in a forthcoming paper.
2665. Spectroscopy of X-ray sources in ECDF-S
ID:
ivo://CDS.VizieR/J/ApJ/693/1713
Title:
Spectroscopy of X-ray sources in ECDF-S
Short Name:
J/ApJ/693/1713
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the first results of our optical spectroscopy program aimed to provide redshifts and identifications for the X-ray sources in the Extended Chandra Deep Field South. A total of 339 sources were targeted using the IMACS spectrograph at the Magellan telescopes and the VIMOS spectrograph at the VLT. We measured redshifts for 186 X-ray sources, including archival data and a literature search. We find that the active galactic nucleus (AGN) host galaxies have on average redder rest-frame optical colors than nonactive galaxies, and that they live mostly in the "green valley". The dependence of the fraction of AGNs that are obscured on both luminosity and redshift is confirmed at high significance and the observed AGN spatial density is compared with the expectations from existing luminosity functions. These AGNs show a significant difference in the mid-IR to X-ray flux ratio for obscured and unobscured AGNs, which can be explained by the effects of dust self-absorption on the former. This difference is larger for lower luminosity sources, which is consistent with the dust opening angle depending on AGN luminosity.
2666. Spectroscopy of 88 z<0.7 SDSS QSOs
ID:
ivo://CDS.VizieR/J/ApJS/201/23
Title:
Spectroscopy of 88 z<0.7 SDSS QSOs
Short Name:
J/ApJS/201/23
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have carried out a systematic search for subparsec supermassive black hole (BH) binaries among z<~0.7 Sloan Digital Sky Survey quasars. These are predicted by models of supermassive BH and host galaxy coevolution, therefore their census and population properties constitute an important test of these models. In our working hypothesis, one of the two BHs accretes at a much higher rate than the other and carries with it the only broad emission line region of the system, making the system analogous to a single-lined spectroscopic binary star. Accordingly, we used spectroscopic principal component analysis to search for broad H{beta} emission lines that are displaced from the quasar rest frame by |{Delta}{nu}|>~1000km/s. This method also yields candidates for rapidly recoiling BHs. Of the 88 candidates, several were previously reported in the literature. We found a correlation between the peak offset and skewness of the broad H{beta} profiles, suggesting a common physical explanation for these profiles. We carried out follow-up spectroscopic observations of 68 objects to search for changes in the peak velocities of the H{beta} lines.
2667. Spectroscopy & V-band monitoring of CTS C30.10
ID:
ivo://CDS.VizieR/J/ApJ/880/46
Title:
Spectroscopy & V-band monitoring of CTS C30.10
Short Name:
J/ApJ/880/46
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report 6yr monitoring of distant bright quasar CTS C30.10 (z=0.90052) with the Southern African Large Telescope. We measured the rest-frame time lag of 562_-68_^+116^ days between the continuum variations and the response of the MgII emission line, using six different methods. This time delay, combined with other available measurements of MgII line delay, mostly for lower-redshift sources, shows that the MgII line reverberation implies a radius-luminosity relation very similar to the one based on a more frequently studied H{beta} line.
2668. Spectrosocopy of the multiple star HT Vir
ID:
ivo://CDS.VizieR/J/other/IBVS/6121
Title:
Spectrosocopy of the multiple star HT Vir
Short Name:
J/other/IBVS/612
Date:
21 Oct 2021
Publisher:
CDS
Description:
The spectra of HT Virginis were collected at 0.5m Newtonian telescope (PST1) equipped with echelle spectrograph (R=40 000). The focal length of the telescope is 2.25m. The data set was obtained between 6 May 2011 and 21 May 2011. The signal-to-noise ratio is from 10 to 85. The collected data covered spectral range from 4288 to 7517{AA}. The continuum of the spectra was normalised to 1 while the wave length scale was not corrected to the heliocentric values. The spectra contain light from the eclipsing pair B and component A which is SBI type (A/B separation is 0.56 arcsec).
2669. Spectrosocpy of NGC 7009
ID:
ivo://CDS.VizieR/J/MNRAS/409/881
Title:
Spectrosocpy of NGC 7009
Short Name:
J/MNRAS/409/881
Date:
21 Oct 2021
Publisher:
CDS
Description:
NGC 7009 is a fascinating example of a high-excitation, elliptical planetary nebula (PN) containing circumnebular rings, and FLIERs and jets along the major axis. We present visual spectroscopy along multiple position angles through the nucleus, taken with the Observatorio Astronomico Nacional (Mexico); mid-infrared (MIR) spectroscopy and imaging acquired using the Infrared Space Observatory (ISO) and Spitzer Space Telescope (SST), and narrow-band imaging obtained using the Hubble Space Telescope (HST).
2670. Spectrospcopy, IR-photom. in globular clusters
ID:
ivo://CDS.VizieR/J/A+A/303/468
Title:
Spectrospcopy, IR-photom. in globular clusters
Short Name:
J/A+A/303/468
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)

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