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1421. Linelists for C3H- from CALPGM
ID:
ivo://CDS.VizieR/J/ApJ/783/36
Title:
Linelists for C3H- from CALPGM
Short Name:
J/ApJ/783/36
Date:
21 Oct 2021
Publisher:
CDS
Description:
Pety et al. have reported the detection of eight transitions of a closed-shell, linear molecule (B11244) in observations toward the Horsehead photodissociation region (PDR), which they attribute to the l-C_3_H^+^ cation. Recent high-level ab initio calculations have called this assignment into question; the anionic C_3_H^-^ molecule has been suggested as a more likely candidate. Here, we examine observations of the Horsehead PDR, Sgr B2(N), TMC-1, and IRC+10216 in the context of both l-C_3_H^+^ and C_3_H^-^. We find no observational evidence of K_a_=1 lines, which should be present were the carrier indeed C_3_H^-^. Additionally, we find a strong anticorrelation between the presence of known molecular anions and B11244 in these regions. Finally, we discuss the formation and destruction chemistry of C_3_H^-^ in the context of the physical conditions in the regions. Based on these results, we conclude there is little evidence to support the claim that the carrier is C_3_H^-^.
1422. Line positions for TiO singlet states
ID:
ivo://CDS.VizieR/J/ApJS/236/46
Title:
Line positions for TiO singlet states
Short Name:
J/ApJS/236/46
Date:
21 Oct 2021
Publisher:
CDS
Description:
A consistent set of spectroscopic constants for the a^1^{Delta}, d^1^{Sigma}^+^, b^1^{Pi}, c^1^{Phi}, and f^1^{Delta} states of ^48^Ti^16^O has been determined from analysis of the b^1^{Pi}-a^1^{Delta}, b^1^{Pi}-d^1^{Sigma}^+^, c^1^{Phi}-a^1^{Delta}, and f^1^{Delta}-a^1^{Delta} systems. Three Fourier transform emission spectra have been used for the analysis. New bands of the b^1^{Pi}-a^1^{Delta} and c^1^{Phi}-a^1^{Delta} systems have been fitted. The first analysis of the c^1^{Phi}-a^1^{Delta} system using Fourier transform spectra is also provided. Extensive and improved line positions are measured. TiO is prominent in the spectra of oxygen-rich cool stellar objects and may be present in hot-Jupiter exoplanet atmospheres.
1423. Line ratios in giant HII region H 1013
ID:
ivo://CDS.VizieR/J/A+A/551/A82
Title:
Line ratios in giant HII region H 1013
Short Name:
J/A+A/551/A82
Date:
21 Oct 2021
Publisher:
CDS
Description:
While collisionally excited lines in HII regions allow one to easily probe the chemical composition of the interstellar medium in galaxies, the possible presence of important temperature fluctuations casts some doubt on the derived abundances. To provide new insights into this question, we have carried out a detailed study of a giant HII region, H1013, located in the galaxy M101, for which many observational data exist and which has been claimed to harbour temperature temperature fluctuations at a level of t^2^=0.03-0.06.
1424. Line ratios in z~2-3 galaxies from KBSS-MOSFIRE
ID:
ivo://CDS.VizieR/J/ApJ/795/165
Title:
Line ratios in z~2-3 galaxies from KBSS-MOSFIRE
Short Name:
J/ApJ/795/165
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present initial results of a deep near-IR spectroscopic survey covering the 15 fields of the Keck Baryonic Structure Survey using the recently commissioned MOSFIRE spectrometer on the Keck 1 telescope. We focus on a sample of 251 galaxies with redshifts 2.0<z<2.6, star formation rates (SFRs) 2<~SFR<~200 M_{sun}_/yr, and stellar masses 8.6<log(M_*_/M_{sun}_)<11.4, with high-quality spectra in both H- and K-band atmospheric windows. We show unambiguously that the locus of z~2.3 galaxies in the "BPT" nebular diagnostic diagram exhibits an almost entirely disjointed, yet similarly tight, relationship between the line ratios [N II] {lambda}6585/H{alpha} and [O III]/H{beta} as compared to local galaxies. Using photoionization models, we argue that the offset of the z~2.3 BPT locus relative to that at z~0 is caused by a combination of harder stellar ionizing radiation field, higher ionization parameter, and higher N/O at a given O/H compared to most local galaxies, and that the position of a galaxy along the z~2.3 star-forming BPT locus is surprisingly insensitive to gas-phase oxygen abundance. The observed nebular emission line ratios are most easily reproduced by models in which the net stellar ionizing radiation field resembles a blackbody with effective temperature T_eff_=50000-60000 K, the gas-phase oxygen abundances lie in the range 0.2<Z/Z_{sun}_<1.0, and the ratio of gas-phase N/O is close to the solar value. We critically assess the applicability at high redshift of commonly used strong line indices for estimating gas-phase metallicity, and consider the implications of the small intrinsic scatter of the empirical relationship between excitation-sensitive line indices and M_*_(i.e., the "mass-metallicity" relation) at z=~2.3.
1425. Lines and continuum sky emission in the NIR
ID:
ivo://CDS.VizieR/J/A+A/581/A47
Title:
Lines and continuum sky emission in the NIR
Short Name:
J/A+A/581/A47
Date:
21 Oct 2021
Publisher:
CDS
Description:
Determining the intensity of lines and continuum airglow emission in the H-band is important for the design of faint-object infrared spectrographs. Existing spectra at low/medium resolution cannot disentangle the true sky-continuum from instrumental effects (e.g. diffuse light in the wings of strong lines). We aim to obtain, for the first time, a high resolution infrared spectrum deep enough to set significant constraints on the continuum emission between the lines in the H-band. During the second commissioning run of the GIANO high-resolution spectrograph at the La Palma Observatory, we pointed the instrument directly to the sky and obtained a deep spectrum that extends from 0.97 to 2.4 micron and includes the whole H-band. The spectrum shows about 1500 emission lines, a factor of two more than in previous works. Of these, 80% are identified as OH transitions; half of these are from highly excited molecules (hot-OH component). The other lines are attributable to O_2_ or unidentified. Several of the faint lines are in spectral regions that were previously believed to be free of lines emission. The continuum in the H-band is marginally detected at a level of about 300photons/m^2^/s/arcsec^2^/um. The observed spectrum and the list of observed sky-lines are published in electronic format. Our measurements indicate that the sky continuum in the H-band could be even darker than previously believed. However, the myriad of airglow emission lines severely limits the spectral ranges where very low background can be effectively achieved with low/medium resolution spectrographs. We identify a few spectral bands that could still remain quite dark at the resolving power foreseen for VLT-MOONS (R~6,600).
1426. Lines in the infrared solar spectrum
ID:
ivo://CDS.VizieR/J/A+AS/113/71
Title:
Lines in the infrared solar spectrum
Short Name:
J/A+AS/113/71
Date:
21 Oct 2021
Publisher:
CDS
Description:
We list 603 spectral lines between 1.0, 1.8um that are judged to be relatively unblended from a visual inspection of spectra of the quiet sun. Much of the atomic data of relevance to studies of solar and stellar magnetism, convection and atmospheric structure are also provided. Particular attention is paid to blending by telluric lines. We determine the level of blending both in the presence and the absence of telluric lines. We also describe how telluric blends may be removed from spectra with high spectral resolution.
1427. Line Spectra of the Elements
ID:
ivo://CDS.VizieR/VI/16
Title:
Line Spectra of the Elements
Short Name:
VI/16
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains wavelength information for 99 different atomic species. The wavelengths for about 46,610 spectral lines of neutral through quadruply ionized atoms are tabulated. The information is presented in a general table of headers and references for each element and for each element a table of relative intensities, wavelengths ordered numerically, chemical elements, and stages of ionization indicated for each line in the wavelength range 40 to 40,000 Angstroms. Listed in the 99 data files are lines that appear in emission from the vacuum ultraviolet to the far infrared. For most atoms these lines are chosen from much larger lists so as to include the stronger observed lines in each spectral region. Below 2000 Angstroms the wavelengths are in vacuum; above 2000 Angstroms the wavelengths are in air. Wavelengths given to three decimal places are suitable for spectrograph calibration purpose such as Ne, Ar, Kr, Fe in the air region and C, N, O, Si, and Cu in the vacuum region. The intensity estimates are useful only as a rough indication of the appearance of a spectrum. The literature references as they appear the the the Handbook of Chemistry and Physics are given in a separate file.
1428. Line spectrum of NGC 7027
ID:
ivo://CDS.VizieR/J/A+A/303/175
Title:
Line spectrum of NGC 7027
Short Name:
J/A+A/303/175
Date:
21 Oct 2021
Publisher:
CDS
Description:
Deep CCD spectra of the planetary nebula NGC 7027, taken over the range 654-1046nm at a spectral resolution of the order of 0.1nm, are presented. About 465 different lines are detected and intensities are provided for 405 features. A total of 680 emission lines is considered.
1429. Line-strength indices for 74 early-type galaxies
ID:
ivo://CDS.VizieR/J/ApJ/691/1862
Title:
Line-strength indices for 74 early-type galaxies
Short Name:
J/ApJ/691/1862
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present line-strength measurements for 74 early-type galaxies in the core of the Coma cluster reaching down to velocity dispersions, {sigma}, of 30km/s. The index-{sigma} relations for our sample, including galaxies with {sigma}<100km/s (low-{sigma}), differ in shape depending on which index is used. We note two types of relations for the metallic indices: one showing a break in the slope around ~100km/s and another group with strong linear relations between an index and log {sigma}. We find no connection between the behavior of index-{sigma} relations with either {alpha}- or Fe-peak elements. However, we find indications that the relations are tighter for indices which do not depend on the microturbulent velocities of stellar atmospheres.
1430. Line-strength indices for 148 early-type galaxies
ID:
ivo://CDS.VizieR/J/A+A/395/431
Title:
Line-strength indices for 148 early-type galaxies
Short Name:
J/A+A/395/431
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have derived high quality line-strength indices and velocity dispersions for a sample of 148 early-type galaxies in different environments. The wavelength region covered by the observations (lambda~4600 to 6600{AA}) includes the Lick/IDS indices Hbeta, Mg_1_, Mg_2_, Mgb, Fe5015, Fe5270, Fe5335, Fe5406, Fe5709, Fe5782, NaD, TiO_1_ and TiO_2_. The data are intended to address possible differences of the stellar populations of early-type galaxies in low- and high-density environments. This paper describes the sample properties, explains the data reduction and presents the complete list of all the measurements. Most galaxies of the sample (85%) had no previous measurements of any Lick/IDS indices and for 30% of the galaxies we present first-time determinations of their velocity dispersions. Special care is taken to identify galaxies with emission lines. We found that 62 per cent of the galaxies in the sample have emission lines, as measured by the equivalent width of the [0III]5007{AA} line, EW[OIII]~>~0.3{AA}.

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