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1061. Spectroscopy of HD 51585 (= OY Gem)
ID:
ivo://CDS.VizieR/J/A+AS/117/281
Title:
Spectroscopy of HD 51585 (= OY Gem)
Short Name:
J/A+AS/117/281
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyse CCD spectroscopic material obtained at the Haute Provence Observatory between 1990 and 1993, covering the wavelength region 380-1100mm. 320 emission lines were measured and identified. Of these about 40% correspond to permitted or forbidden lines of ionized iron. Many forbidden lines (20% of the total) are present, including many classic nebular lines. We also provide a comparison of our results with those of other authors. The equivalent width measurements permit to follow in detail the variations of the lines of several elements over the three years and to compare them to variations reported by other authors. On our material the largest variations correspond to helium, which varied by a factor of two and are not in phase with the variations of hydrogen. Many helium lines exhibit P Cyg type profiles, indicating strong outflow of matter from the star. The lines of other elements follow either the variations of the helium or of the hydrogen lines. The radial velocity varies over the years, with an amplitude of more than 60km/s.
1062. 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.
1063. 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.
1064. 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.
1065. 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.
1066. 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.
1067. Spectroscopy of MWC 158 = HD 50138
ID:
ivo://CDS.VizieR/J/A+AS/128/475
Title:
Spectroscopy of MWC 158 = HD 50138
Short Name:
J/A+AS/128/475
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 3738-10232 A of the spectrum of HD 50138 Over two hundred features are identified and a comparison of our results with those of other authors is provided. We also discuss the variability of the lines using equivalent widths and descriptions of the line spectrum. We attribute as a best compromise a spectral type of B 5 III. We conclude that the gaseous shell surrounding the star has a temperature of the order of 10 000K and that its distance to the star is of the order of two stellar radii. We discuss the relation of this star to others previously analyzed and warn against hasty generalizations.
1068. Spectroscopy of of IC4499 red giants
ID:
ivo://CDS.VizieR/J/MNRAS/411/1536
Title:
Spectroscopy of of IC4499 red giants
Short Name:
J/MNRAS/411/1536
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present radial velocity and metallicity measurements for the far southern Galactic globular cluster IC 4499. We selected several hundred target red giant stars in and around the cluster from the 2MASS point source catalogue, and obtained spectra at the near-infrared calcium triplet using the AAOmega spectrograph. Observations of giants in globular clusters M4, M22 and M68 were taken to provide radial velocity and metallicity comparison objects.
1069. Spectroscopy of Southern warm IR galaxies
ID:
ivo://CDS.VizieR/J/ApJS/132/37
Title:
Spectroscopy of Southern warm IR galaxies
Short Name:
J/ApJS/132/37
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper, we present high-resolution optical spectra and optical classifications from our large sample of 285 warm infrared galaxies 10^8^<L_IR_<10^12.5^L_{sun}_. We have classified these galaxies using new theoretical lines on the standard optical diagnostic diagrams. We use a theoretical extreme mixing line between the starburst and AGN regions to classify LINER galaxies and we define a theoretical boundary separating AGNs from starbursts. We find that many galaxies previously classified as LINERs appear to lie on a mixing sequence between starburst and AGN type galaxies.
1070. Spectroscopy of stars in the Galaxy's nuclear cluster
ID:
ivo://CDS.VizieR/J/ApJ/703/1323
Title:
Spectroscopy of stars in the Galaxy's nuclear cluster
Short Name:
J/ApJ/703/1323
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on the structure of the nuclear star cluster in the innermost 0.16pc of the Galaxy as measured by the number density profile of late-type giants. Using laser guide star adaptive optics in conjunction with the integral field spectrograph, OSIRIS, at the Keck II telescope, we are able to differentiate between the older, late-type (~1Gyr) stars, which are presumed to be dynamically relaxed, and the unrelaxed young (~6Myr) population. This distinction is crucial for testing models of stellar cusp formation in the vicinity of a black hole, as the models assume that the cusp stars are in dynamical equilibrium in the black hole potential. In the survey region, we classified 60 stars as early-type (O and early B; 22 newly identified) and 74 stars as late-type (K and M; 61 newly identified). We find that contamination from young stars is significant, with more than twice as many young stars as old stars in our sensitivity range (K'<15.5) within the central arcsecond.