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2601. Spectroscopy of Grus II, Tuc IV and Tuc V
ID:
ivo://CDS.VizieR/J/ApJ/892/137
Title:
Spectroscopy of Grus II, Tuc IV and Tuc V
Short Name:
J/ApJ/892/137
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Magellan/IMACS spectroscopy of three recently discovered ultra-faint Milky Way satellites, Grus II, Tucana IV, and Tucana V. We measure systemic velocities of v_hel_=-110.0+/-0.5km/s, v_hel_=15.9_-1.7_^+1.8^km/s, and v_hel_=-36.2_-2.2_^+2.5^km/s for the three objects, respectively. Their large relative velocities demonstrate that the satellites are unrelated despite their close physical proximity. We determine a velocity dispersion for Tuc IV of {sigma}=4.3_-1.0_^+1.7^km/s, but we cannot resolve the velocity dispersions of the other two systems. For Gru II, we place an upper limit (90% confidence) on the dispersion of {sigma}<1.9km/s, and for Tuc V, we do not obtain any useful limits. All three satellites have metallicities below [Fe/H]=-2.1, but none has a detectable metallicity spread. We determine proper motions for each satellite based on Gaia astrometry and compute their orbits around the Milky Way. Gru II is on a tightly bound orbit with a pericenter of 25_-7_^+6^kpc and orbital eccentricity of 0.45_-0.05_^+0.08^. Tuc V likely has an apocenter beyond 100kpc and could be approaching the Milky Way for the first time. The current orbit of Tuc IV is similar to that of Gru II, with a pericenter of 25_-8_^+11^kpc and an eccentricity of 0.36_-0.06_^+0.13^. However, a backward integration of the position of Tuc IV demonstrates that it collided with the Large Magellanic Cloud at an impact parameter of 4kpc ~120Myr ago, deflecting its trajectory and possibly altering its internal kinematics. Based on their sizes, masses, and metallicities, we classify Gru II and Tuc IV as likely dwarf galaxies, but the nature of Tuc V remains uncertain.
2602. Spectroscopy of H{alpha} blue stars in M 33
ID:
ivo://CDS.VizieR/J/PAZh/25/18
Title:
Spectroscopy of H{alpha} blue stars in M 33
Short Name:
J/PAZh/25/18
Date:
21 Oct 2021
Publisher:
CDS
Description:
Multiobject spectroscopy for 118 blue stars with an H{alpha} excess in the galaxy M 33 from the lists of SS 433 and LBV candidates and other rare types of massive stars is presented. The H{alpha} parameters and the relative intensities of the [NII]6584{AA} and [SII]6716{AA} lines are given. We identified stars with a broad H{alpha} emission line, which is probably emitted in the stellar wind.
2603. Spectroscopy of HD 45166
ID:
ivo://CDS.VizieR/J/A+A/444/895
Title:
Spectroscopy of HD 45166
Short Name:
J/A+A/444/895
Date:
21 Oct 2021
Publisher:
CDS
Description:
The binary star HD 45166 has been observed since 1922 but its orbital period has not yet been found. It is considered a peculiar Wolf-Rayet star, and its assigned classification has varied. For this reason we included the object as a candidate V Sge star and performed spectroscopy in order to search for its putative orbital period. High-resolution spectroscopic observations show that the spectrum, in emission and in absorption, is quite rich. The emission lines have great diversity of widths and profiles. The full widths at half maximum vary from 70km/s for the weakest lines up to 370km/s for the most intense ones. The Hydrogen and Helium lines are systematically broader than the CNO lines. Assuming that HD 45166 is a double-line spectroscopic binary, it present s an orbital period of P=1.596+/-0.003-day, with an eccentricity of e=0.18+/-0.08. In addition, a search for periodicity using standard techniques reveals that the emission lines present at least two other periods, of 5 and 5 hour. The secondary star has a spectral type of B7 V and, therefore, should have a mass of about M=4.8M_{sun}_. Given the radial velocity amplitudes, we determined the mass of the hot (primary) star as M=4.2+/-0.7M_{sun}_ and the inclination angle of the system, i=0.77+/-0.09deg. As the eccentricity of the orbit is non zero, the Roche lobes increase and decrease as a function of the orbital phase. At periastron, the secondary star fills its Roche lobe. The distance to the star has been re-determined as d=1.3+/-0.2kpc and a color excess of E(B-V)=0.155+/-0.007 has been derived. This implies an absolute B magnitude of -0.6 for the primary star and -0.7 for the B7 star. We suggest that the discrete absorption components (DACs) observed in the ultraviolet with a periodicity similar to the orbital period may be induced by periastron events.
2604. Spectroscopy of HD 86222
ID:
ivo://CDS.VizieR/J/A+A/564/A26
Title:
Spectroscopy of HD 86222
Short Name:
J/A+A/564/A26
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present spectroscopic and photometric analysis of the quintuple star HD 86222 with an eclipsing component. Until now three visual components A, B, and C of this multiple star were known. Four components in the A/B pair were detected during the examination of the cross correlation functions obtained from the spectra.
2605. Spectroscopy of HD 45677 = MWC 142
ID:
ivo://CDS.VizieR/J/A+AS/124/441
Title:
Spectroscopy of HD 45677 = MWC 142
Short Name:
J/A+AS/124/441
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 regions 3750-5112 and 7065-10212{AA} of the spectrum of HD 45677. Over 235 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 the line spectrum. We conclude that the gaseous shell surrounding the star has a temperature of the order of 7000K and that its distance to the star is less than ten stellar radii. We discuss the similarity of this star to other stars previously analyzed.
2606. 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.
2607. Spectroscopy of Herschel Dwarf Galaxy Survey
ID:
ivo://CDS.VizieR/J/A+A/578/A53
Title:
Spectroscopy of Herschel Dwarf Galaxy Survey
Short Name:
J/A+A/578/A53
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Herschel PACS spectroscopic observations of the [CII] 157um, [OI] 63 and 145um, [OIII] 88um, [NII] 122 and 205um, and [NIII] 57um fine-structure cooling lines in a sample of 48 low-metallicity star-forming galaxies of the guaranteed time key program Dwarf Galaxy Survey. We correlate PACS line ratios and line-to-LTIR ratios with LTIR, LTIR/LB, metallicity, and FIR color, and interpret the observed trends in terms of ISM conditions and phase filling factors with Cloudy radiative transfer models. We find that the ISM of low-metallicity dwarf galaxies has a more porous structure than that of metal-rich galaxies. The radiation fields are harder and the the ionized gas/PDR filling factor is larger in the dwarfs.
2608. Spectroscopy of HII regions in nearby galaxies
ID:
ivo://CDS.VizieR/J/A+A/546/A2
Title:
Spectroscopy of HII regions in nearby galaxies
Short Name:
J/A+A/546/A2
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this work we analyze the spectroscopic properties of a large number of HII regions, ~2600, located in 38 galaxies. The sample of galaxies has been assembled from the face-on spirals in the PINGS survey and a sample described in Marmol-Queralto (2011A&A...534A...8M). All the galaxies were observed using Integral Field Spectroscopy with a similar setup, covering their optical extension up to ~2.4 effective radii within a wavelength range from ~3700 to ~6900{AA}. We develop a new automatic procedure to detect HII regions, based on the contrast of the H{alpha} intensity maps extracted from the datacubes. Once detected, the procedure provides us with the integrated spectra of each individual segmented region. In total, we derive good quality spectroscopic information for ~2600 independent HII regions/complexes. This is by far the largest nearby 2-dimensional spectroscopic survey presented on this kind of regions up-to-date. Even more, our selection criteria and dataset guarantee that we cover the regions in an unbiased way, regarding the spatial sampling. A well-tested automatic decoupling procedure has been applied to remove the underlying stellar population, deriving the main properties (intensity, dispersion and velocity) of the strongest emission lines in the considered wavelength range (covering from [OII]3727 to [SII]6731). A final catalogue of the spectroscopic properties of these regions has been created for each galaxy.
2609. Spectroscopy of H_2_ towards HH91A
ID:
ivo://CDS.VizieR/J/A+A/474/941
Title:
Spectroscopy of H_2_ towards HH91A
Short Name:
J/A+A/474/941
Date:
21 Oct 2021
Publisher:
CDS
Description:
Optical and near-infrared spectroscopy of molecular hydrogen in interstellar shocks provide a very powerful probe of the physical conditions that prevail in interstellar shocks. Integral-field spectroscopy of H_2_ in the optical wavelength region and complementary long-slit near-infrared spectroscopy towards HH91A are used to characterize the ro-vibrational population distribution among H_2_ levels with excitation energies up to 30000cm^-1^.
2610. Spectroscopy of 7 INTEGRAL X-ray sources
ID:
ivo://CDS.VizieR/J/A+A/484/783
Title:
Spectroscopy of 7 INTEGRAL X-ray sources
Short Name:
J/A+A/484/783
Date:
21 Oct 2021
Publisher:
CDS
Description:
The INTEGRAL hard X-ray observatory has revealed an emerging population of highly obscured X-ray binary systems through multi-wavelength observations. Previous studies have shown that many of these sources are high-mass X-ray binaries hosting neutron stars orbiting around luminous and evolved companion stars. To better understand this newly-discovered population, we have selected a sample of sources for which an accurate localisation is available to identify the stellar counterpart and reveal the nature of the companion star and of the binary system.

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