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1741. Near Infrared Spectra of Normal Stars
ID:
ivo://CDS.VizieR/III/181
Title:
Near Infrared Spectra of Normal Stars
Short Name:
III/181
Date:
21 Oct 2021
Publisher:
CDS
Description:
The authors present digital spectra of O to M stars, luminosity classes V, III, and Ib in the wavelength range 5750-8950{AA}, at 15.5{AA} resolution. The stars follow well defined morphological sequences in both temperature and luminosity. This wavelength region and resolution, combined with the high sensitivity of silicon-based detectors, are very useful for spectral classification. Details of the observations, identifications of the main spectral features, and spectral lines most sensitive to temperature and luminosity are given in the paper.
1742. Near-infrared spectra of 27 SDSS quasars
ID:
ivo://CDS.VizieR/J/ApJ/640/579
Title:
Near-infrared spectra of 27 SDSS quasars
Short Name:
J/ApJ/640/579
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a near-infrared quasar composite spectrum spanning the wavelength range 0.58-3.5um. The spectrum has been constructed from observations of 27 quasars obtained at the NASA IRTF telescope and satisfying the criteria Ks<14.5 and M_i_<-23; the redshift range is 0.118<z<0.418. The signal-to-noise ratio is moderate, reaching a maximum of 150 between 1.6 and 1.9um. While a power-law fit to the continuum of the composite spectrum requires two breaks, a single power-law slope of alpha=-0.92 plus a 1260K blackbody provides an excellent description of the spectrum from H{alpha} to 3.5um, strongly suggesting the presence of significant quantities of hot dust in this blue-selected quasar sample. We measure intensities and line widths for 10 lines, finding that the Paschen line ratios rule out case B recombination. We compute K-corrections for the J, H, K, and Spitzer 3.6um bands, which will be useful in analyzing observations of quasars up to z=10.
1743. Near-IR IFU spectroscopy of HH99B
ID:
ivo://CDS.VizieR/J/A+A/481/123
Title:
Near-IR IFU spectroscopy of HH99B
Short Name:
J/A+A/481/123
Date:
21 Oct 2021
Publisher:
CDS
Description:
We aim at characterising the morphology and the physical parameters governing the shock physics of the Herbig-Haro object HH99B. We obtained SINFONI-SPIFFI IFU spectroscopy (R~2000-4000) between 1.10 and 2.45{mu}m detecting more than 170 emission lines, that, to a large extent, have never observed before in a Herbig-Haro object. Most of them come from ro-vibrational transitions of molecular hydrogen (v_up_<=7, E_up_~<38000K) and [FeII] (E_up_~<30000K). In addition, we observed several hydrogen and helium recombination lines, along with fine-structure lines of ionic species. All the brightest lines appear resolved in velocity. Intensity ratios of ionic lines were compared with predictions of NLTE models to derive bi-dimensional maps of extinction and electron density, along with estimates of temperature, fractional ionisation, and atomic hydrogen post-shock density. The H2 line intensities were interpreted in the framework of Boltzmann diagrams, from which we have derived extinction and temperature maps of the molecular gas. From the intensity maps of bright lines (i.e. H2 2.122{mu}m and [FeII]1.644{mu}m), the kinematical properties of the shock(s) at work in the region were delineated. Finally, from selected [FeII] lines, constraints on the spontaneous emission coefficients of the 1.257, 1.321, and 1.644{mu}m lines are provided.
1744. Near-IR integral field spectra of 15 M-L dwarfs
ID:
ivo://CDS.VizieR/J/A+A/562/A127
Title:
Near-IR integral field spectra of 15 M-L dwarfs
Short Name:
J/A+A/562/A127
Date:
21 Oct 2021
Publisher:
CDS
Description:
At young ages, low surface gravity affects the atmospheric properties of ultracool dwarfs. The impact on medium-resolution near-infrared (NIR) spectra has only been slightly investigated at the M-L transition sofar. We present a library of near-infrared (1.1-2.45um) medium-resolution (R~1500-2000) integral field spectra of 15 young M6-L0 dwarfs. We aim at deriving updated NIR spectral type, luminosity and physical parameters (Teff, logg, M, L/L_{sun}_) of each source. This work also aims at testing the latest generation of BT-SETTL atmospheric models. We estimated spectral types using spectral indices and spectra of reference young objects classified in the optical. We used the 2010 and 2012 releases of the BT-SETTL synthetic spectral grid and cross-checked the results with the DRIFT-PHOENIX models to derive the atmospheric properties of the sources.
1745. Near-IR spectral atlas of OB stars
ID:
ivo://CDS.VizieR/J/ApJS/161/154
Title:
Near-IR spectral atlas of OB stars
Short Name:
J/ApJS/161/154
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present intermediate-resolution (R~8000-12000) high signal-to-noise (S/N) H- and K-band spectroscopy of a sample of 37 optically visible stars, ranging in spectral type from O3 to B3 and representing most luminosity classes. Spectra of this quality can be used to constrain the temperature, luminosity, and general wind properties of OB stars, when used in conjunction with sophisticated atmospheric model codes. Most important is the need for moderately high resolutions (R>=5000) and very high signal-to-noise (S/N>=150) spectra for a meaningful profile analysis. When using near-infrared spectra for a classification system, moderately high signal-to-noise (S/N~100) is still required, though the resolution can be relaxed to just a thousand or two. In the Appendix we provide a set of very high-quality near-infrared spectra of Brackett lines in six early-A dwarfs. These can be used to aid in the modeling and removal of such lines when early-A dwarfs are used for telluric spectroscopic standards.
1746. Near-IR spectral library of late-type stars
ID:
ivo://CDS.VizieR/J/ApJS/151/387
Title:
Near-IR spectral library of late-type stars
Short Name:
J/ApJS/151/387
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an empirical infrared spectral library of medium-resolution (R~2000-3000) H (1.6{mu}m) and K (2.2{mu}m) band spectra of 218 red stars, spanning a range of [Fe/H] from ~-2.2 to ~+0.3. The sample includes Galactic disk stars, bulge stars from Baade's window, and red giants from Galactic globular clusters. We report the values of 19 indices covering 12 spectral features measured from the spectra in the library. Finally, we derive calibrations to estimate the effective temperature, and diagnostic relationships to determine the luminosity classes of individual stars from near-infrared spectra. This paper is part of a larger effort aimed at building a near-IR spectral library to be incorporated in population synthesis models, as well as at testing synthetic stellar spectra.
1747. Near-IR spectra of 7 Be stars and AG Car
ID:
ivo://CDS.VizieR/J/A+AS/121/113
Title:
Near-IR spectra of 7 Be stars and AG Car
Short Name:
J/A+AS/121/113
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present and discuss {lambda} 6470-8780 spectra of 7 poorly-studied Be stars and of one Luminous Blue Variable (AG Car), and give equivalent widths and radial velocities of selected spectral lines.
1748. Near-IR spectra of extremely red AGB stars
ID:
ivo://CDS.VizieR/J/MNRAS/400/1413
Title:
Near-IR spectra of extremely red AGB stars
Short Name:
J/MNRAS/400/1413
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a library of 139 near-IR spectra of cool asymptotic giant branch stars that will be useful for comparison with theoretical model atmosphere calculations and for modelling the integrated emission from intermediate-age stellar populations. The source list was selected from the 'extremely red' region of the Isaac Newton Telescope (INT) Photometric H{alpha} Survey (IPHAS) colour-colour plane that is overwhelmingly dominated by very late-type stars. The spectral library also includes a large fraction of S-type and carbon stars. We present a number of spectral classification sequences highlighting the various molecular features identified and discuss a number of rare features with uncertain identifications in the literature. With its focus on particularly cool photospheres, this catalogue serves as a companion to recent spectroscopic atlases of MK standards in the near-IR. Finally, the relationship between IPHAS (r'-i') and (r'-H{alpha}) colours and spectroscopically determined properties is discussed and a strong correlation between the (r'-H{alpha}) colour and the C/O abundance index for S-type and carbon stars is noted. This relation has the potential to separate O-rich, S-type and carbon stars in the Galaxy based on their photometry alone.
1749. Near-IR spectra of inner red giants
ID:
ivo://CDS.VizieR/J/A+A/479/131
Title:
Near-IR spectra of inner red giants
Short Name:
J/A+A/479/131
Date:
21 Oct 2021
Publisher:
CDS
Description:
The existence in the Milky Way of either a long thin bar with a half length of 4.5kpc and a position angle of around 45{deg} with respect to the Sun-Galactic centre line or a bulge+bar complex, thicker and shorter, with a smaller tilt respect to the Sun-GC line, has been a matter of discussion in recent decades. In this paper, we present low resolution (R=500) near-infrared spectra for selected and serendipitous sources in six inner in-plane Galactic fields at l=7{deg}, 12{deg}, 15{deg}, 20{deg}, 26{deg} and 27{deg}, with the aim of analysing the stellar content present in those fields.
1750. Near-IR spectra of LMC globular clusters
ID:
ivo://CDS.VizieR/J/A+A/543/A75
Title:
Near-IR spectra of LMC globular clusters
Short Name:
J/A+A/543/A75
Date:
21 Oct 2021
Publisher:
CDS
Description:
The rest-frame near-IR spectra of intermediate age (1-2Gyr) stellar populations are dominated by carbon based absorption features offering a wealth of information. Yet, spectral libraries that include the near-IR wavelength range do not sample a sufficiently broad range of ages and metallicities to allow for accurate calibration of stellar population models and thus the interpretation of the observations. In this paper we investigate the integrated J- and H-band spectra of six intermediate age and old globular clusters in the Large Magellanic Cloud (LMC).

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