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2621. Spectroscopy of IRC +10420
ID:
ivo://CDS.VizieR/J/A+AS/129/541
Title:
Spectroscopy of IRC +10420
Short Name:
J/A+AS/129/541
Date:
21 Oct 2021
Publisher:
CDS
Description:
A high resolution optical spectrum of the post-red supergiant candidate IRC +10420 is presented. The Utrecht Echelle Spectrograph observations, with a total integration time of more than 9 hours provide a spectral coverage from 3850 A to 1micron, and a spectral resolution of 9km/s. The spectrum is shown, and an identification list of lines in the spectrum is provided. From a preliminary analysis of the spectrum we find that the spectral type of IRC+10420 has changed from F8I+ in 1973 to mid- to early A type now, confirming the results of Oudmaijer et al. (1996MNRAS.280.1062O), who claimed a change in temperature based on photometric changes. It is shown that most of the emission lines in the spectrum of IRC +10420 are blue-shifted with respect to the systemic velocity traced by circumstellar rotational CO emission, while the (few) absorption lines - with the exception of some high excitation lines - are red-shifted by 25km/s, which may suggest infall of material onto the star. Finally, it is found that the interstellar extinction towards IRC +10420, as traced by the Diffuse Interstellar Bands is very large, with an inferred E(B-V) of 1.4+/-0.5 compared to a total E(B-V) of 2.4. This table provides the line identifications for the measured spectral lines from atomic species. Listed in the table are respectively the laboratory wavelength (in air) taken from Moore (1945, in A multiplet table of astrophysical interest, Contribution from the Princeton University Observatory No. 20.), the line identification (ion and multiplet), the energies of the lower levels of the transitions in eV, and the log(gf). The latter two values are taken from Wiese et al. (1966, Nat. Stand. Ref. Data Ser. 20 and 1969, Nat. Stand. Ref. Data Ser. 22), Martin et al. (1988, Cat. <VI/72>) and Fuhr et al. (1988, Cat. <VI/72>). The spectral lines that are marked `UN' were not identified, the wavelength given for these lines is the observed wavelength. Then next entries in the table are the velocity shift of the centres of spectral lines (in LSR), the equivalent width in milli-Angstrom, and the full-width-at-half maximum of the fit in Angstrom. The velocity shifts have been measured by fitting Gaussian profiles through the lines, the equivalent widths have been measured by integrating the line over the continuum. In the case of overlapping lines, the lines were de-composed by fitting multiple Gaussian components to the profiles. In these cases (marked with `deb.' in the table) the equivalent widths are the areas under the Gaussian fits. Equivalent widths for lines that could not be deblended, are given between brackets. These values represent the total equivalent width of the lines concerned.
2622. Spectroscopy of irregular variables
ID:
ivo://CDS.VizieR/J/A+AS/131/119
Title:
Spectroscopy of irregular variables
Short Name:
J/A+AS/131/119
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results of optical spectroscopy of 169 southern and equatorial objects previously known as irregular variables are presented. The targets were selected via photoelectric UBV photometry among objects classified as L, L:, I, I:, IS and IS: in the General Catalogue of Variable Stars and New Catalogue of Suspected Variable Stars. Among these objects we have identified 8 cataclysmic variables, 8 symbiotic stars and stars that belong to a variety of other classes.
2623. Spectroscopy of 26 lensing cluster cores
ID:
ivo://CDS.VizieR/J/ApJS/193/8
Title:
Spectroscopy of 26 lensing cluster cores
Short Name:
J/ApJS/193/8
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from a spectroscopic program targeting 26 strong-lensing cluster cores that were visually identified in the Sloan Digital Sky Survey (SDSS; Gladders et al. 2011, in prep) and the Second Red-Sequence Cluster Survey (RCS-2; Bayliss et al. 2011, in prep). The 26 galaxy cluster lenses span a redshift range of 0.2<z<0.65, and our spectroscopy reveals 69 unique background sources with redshifts as high as z=5.200. We also identify redshifts for 262 cluster member galaxies and measure the velocity dispersions and dynamical masses for 18 clusters where we have redshifts for N>=10 cluster member galaxies. We account for the expected biases in dynamical masses of strong-lensing-selected clusters as predicted by results from numerical simulations and discuss possible sources of bias in our observations.
2624. Spectroscopy of low-metallicity star candidates
ID:
ivo://CDS.VizieR/J/ApJ/870/122
Title:
Spectroscopy of low-metallicity star candidates
Short Name:
J/ApJ/870/122
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results from an observing campaign to identify low-metallicity stars in the Best & Brightest Survey. From medium-resolution (R~1200-2000) spectroscopy of 857 candidates, we estimate the stellar atmospheric parameters (T_eff_, logg, and [Fe/H]), as well as carbon and {alpha}-element abundances. We find that 69% of the observed stars have [Fe/H]<=-1.0, 39% have [Fe/H]<=-2.0, and 2% have [Fe/H]<=-3.0. There are also 133 carbon-enhanced metal-poor (CEMP) stars in this sample, with 97 CEMP Group I and 36 CEMP Group II stars identified in the A(C) versus [Fe/H] diagram. A subset of the confirmed low-metallicity stars were followed-up with high-resolution spectroscopy, as part of the R-process Alliance, with the goal of identifying new highly and moderately r-process-enhanced stars. Comparison between the stellar atmospheric parameters estimated in this work and from high-resolution spectroscopy exhibit good agreement, confirming our expectation that medium-resolution observing campaigns are an effective way of selecting interesting stars for further, more targeted, efforts.
2625. Spectroscopy of luminous compact blue galaxies
ID:
ivo://CDS.VizieR/J/ApJ/817/87
Title:
Spectroscopy of luminous compact blue galaxies
Short Name:
J/ApJ/817/87
Date:
21 Oct 2021
Publisher:
CDS
Description:
Luminous Compact Blue Galaxies (LCBGs) are an extreme star-bursting population of galaxies that were far more common at earlier epochs than today. Based on spectroscopic and photometric measurements of LCBGs in massive (M>10^15^M_{sun}_), intermediate redshift (0.5<z<0.9) galaxy clusters, we present their rest-frame properties including star formation rate, dynamical mass, size, luminosity, and metallicity. The appearance of these small, compact galaxies in clusters at intermediate redshift helps explain the observed redshift evolution in the size-luminosity relationship among cluster galaxies. In addition, we find the rest-frame properties of LCBGs appearing in galaxy clusters are indistinguishable from field LCBGs at the same redshift. Up to 35% of the LCBGs show significant discrepancies between optical and infrared indicators of star formation, suggesting that star formation occurs in obscured regions. Nonetheless, the star formation for LCBGs shows a decrease toward the center of the galaxy clusters. Based on their position and velocity, we estimate that up to 10% of cluster LCBGs are likely to merge with another cluster galaxy. Finally, the observed properties and distributions of the LCBGs in these clusters lead us to conclude that we are witnessing the quenching of the progenitors of dwarf elliptical galaxies that dominate the number density of present-epoch galaxy clusters.
2626. Spectroscopy of main-belt Ch/Cgh-type asteroids
ID:
ivo://CDS.VizieR/J/AJ/152/54
Title:
Spectroscopy of main-belt Ch/Cgh-type asteroids
Short Name:
J/AJ/152/54
Date:
21 Oct 2021
Publisher:
CDS
Description:
CM chondrites are the most common type of hydrated meteorites, making up ~1.5% of all falls. Whereas most CM chondrites experienced only low-temperature (~0{deg}C-120{deg}C) aqueous alteration, the existence of a small fraction of CM chondrites that suffered both hydration and heating complicates our understanding of the early thermal evolution of the CM parent body(ies). Here, we provide new constraints on the collisional and thermal history of CM-like bodies from a comparison between newly acquired spectral measurements of main-belt Ch/Cgh-type asteroids (70 objects) and existing laboratory spectral measurements of CM chondrites. It first appears that the spectral variation observed among CM-like bodies is essentially due to variations in the average regolith grain size. Second, the spectral properties of the vast majority (unheated) of CM chondrites resemble both the surfaces and the interiors of CM-like bodies, implying a "low" temperature (<300{deg}C) thermal evolution of the CM parent body(ies). It follows that an impact origin is the likely explanation for the existence of heated CM chondrites. Finally, similarly to S-type asteroids and (2) Pallas, the surfaces of large (D>100km) - supposedly primordial - Ch/Cgh-type main-belt asteroids likely expose the interiors of the primordial CM parent bodies, a possible consequence of impacts by small asteroids (D<10km) in the early solar system.
2627. Spectroscopy of M81 globular clusters
ID:
ivo://CDS.VizieR/J/AJ/139/2620
Title:
Spectroscopy of M81 globular clusters
Short Name:
J/AJ/139/2620
Date:
21 Oct 2021
Publisher:
CDS
Description:
We obtained spectra of 74 globular clusters (GCs) in M81. These GCs had been identified as candidates in a Hubble Space Telescope (HST) Advanced Camera for Surveys I-band survey. Sixty-eight of these 74 clusters lie within 7' of the M81 nucleus. Sixty-two of these clusters are newly spectroscopically confirmed, more than doubling the number of confirmed M81 GCs from 46 to 108. We determined metallicities for our 74 observed clusters using an empirical calibration based on Milky Way GCs.
2628. Spectroscopy of MWC 297
ID:
ivo://CDS.VizieR/J/A+AS/131/479
Title:
Spectroscopy of MWC 297
Short Name:
J/A+AS/131/479
Date:
21 Oct 2021
Publisher:
CDS
Description:
On the basis of spectroscopic CCD material obtained at the Haute Provence Observatory, we provide line identifications and equivalent width measurements in the wavelength region 4100-8900{AA} of the spectrum of MWC 297. About two hundred features are identified, almost exclusively emission lines. Only one interstellar feature could be identified ({lambda}6613) a fact which contrasts with the eigth magnitudes of extinction found by photometrists. The spectrum of the underlying star corresponds probably to a late O or early B-type object. The cooler emission lines correspond to a spectrum of a middle A-type star. Analogies with other stars observed in this series of papers are examined.
2629. Spectroscopy of MWC 645
ID:
ivo://CDS.VizieR/J/A+AS/120/99
Title:
Spectroscopy of MWC 645
Short Name:
J/A+AS/120/99
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyse spectroscopic CCD material obtained at the Haute Provence Observatory. We provide identifications and equivalent width measurements in the wavelength region 3740-8790. About 350 emissions lines were measured and about 88 of them were identified. A comparison of our results with those of other authors is provided, as well as a table of elements identified in the spectrum of this star. The pattern of elements present is analogous to that of a late B-type star, but some exceptions are noted, such as the absence of Ne and Mg lines and the presence of K, Cu and Zr lines which appear usually in later type stars. We review the little which is known concerning this object and we also present a quantitative account of the variations in equivalent widths. The observations indicate that the spectrum is highly variable, so that in two different years only half of the lines appear on both spectra. Furthermore variations by at least a factor of two in the equivalent widths are present in many lines. The radial velocity derived from the emission lines (-76km/s) corresponds to that of the shell which probably has a velocity of about 50km/s with respect to the underlying star.
2630. Spectroscopy of MWC 349 A
ID:
ivo://CDS.VizieR/J/A+AS/118/495
Title:
Spectroscopy of MWC 349 A
Short Name:
J/A+AS/118/495
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyse spectroscopic CCD material obtained at the Haute Provence Observatory. We provide line identifications and equivalent width measurements in the wavelength region 3700-8790A. Over 300 emission features are identified and a comparison of our results with those of other authors is provided, as well as a table of all elements which have been identified in the spectrum of the object. The pattern of elements present is analogous to that of B-type stars, but some exceptions are noted, such as the absence of C, Al and Mn. We review the present knowledge of the spectrum variability of MWC 349A. The observations indicate th at the equivalent widths of the lines of many elements vary by factors of up to two. We also provide a list of diffuse interstellar features observed. The latter lead to an average (B-V) excess of about two magnitudes, which is less than what is expected for an object having an interstellar extinction of 10-11 magnitudes.

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