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- ID:
- ivo://CDS.VizieR/J/A+A/578/A11
- Title:
- Spectrum of QSO XMMC 2028
- Short Name:
- J/A+A/578/A11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Gas outflows are believed to play a pivotal role in shaping galaxies, as they regulate both star formation and black hole growth. Despite their ubiquitous presence, the origin and the acceleration mechanism of such powerful and extended winds is not yet understood. Direct observations of the cold gas component in objects with detected outflows at other wavelengths are needed to assess the impact of the outflow on the host galaxy interstellar medium (ISM). We observed with the Plateau de Bure Interferometer an obscured quasar at z Gas outflows are believed to play a pivotal role in shaping galaxies, as they regulate both star formation and black hole growth. Despite their ubiquitous presence, the origin and the acceleration mechanism of such powerful and extended winds is not yet understood. Direct observations of the cold gas component in objects with detected outflows at other wavelengths are needed to assess the impact of the outflow on the host galaxy interstellar medium (ISM). We observed with the Plateau de Bure Interferometer an obscured quasar at z~1.5, XID2028, for which the presence of an ionised outflow has been unambiguously signalled by NIR spectroscopy. The detection of ^12^CO(3-2) emission in this source allows us to infer the molecular gas content and compare it to the ISM mass derived from the dust emission. We then analyze the results in the context of recent insights on scaling relations, which describe the gas content of the overall population of star-forming galaxies at a similar redshifts.
2623. Spectrum of SXP1062
- ID:
- ivo://CDS.VizieR/J/A+A/556/A139
- Title:
- Spectrum of SXP1062
- Short Name:
- J/A+A/556/A139
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Be/X-ray binary SXP 1062 is of especial interest owing to the large spin period of the neutron star, its large spin-down rate, and the association with a supernova remnant constraining its age. This makes the source an important probe for accretion physics. To investigate the long-term evolution of the spin period and associated spectral variations, we performed an XMM-Newton target-of-opportunity observation of SXP 1062 during X-ray outburst. Spectral and timing analysis of the XMM-Newton data was compared with previous studies, as well as complementary Swift/XRT monitoring and optical spectroscopy with the SALT telescope were obtained. The spin period was measured to be Ps=(1071.01+/-0.16)s on 2012 Oct 14. The X-ray spectrum is similar to that of previous observations. No convincing cyclotron absorption features, which could be indicative for a high magnetic field strength, are found. The high-resolution RGS spectra indicate the presence of emission lines, which may not completely be accounted for by the SNR emission. The comparison of multi-epoch optical spectra suggest an increasing size or density of the decretion disc around the Be star. SXP 1062 showed a net spin-down with an average of dPs/dt=(2.27+/-0.44)s/yr over a baseline of 915 days.
- ID:
- ivo://CDS.VizieR/J/MNRAS/447/817
- Title:
- Spectrum of the planetary nebula NGC 6210
- Short Name:
- J/MNRAS/447/817
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- High-resolution spectroscopy of NGC 6210, show that recombination line abundances of O^+2^ and Ne^+2^ are two to three times larger than forbidden line abundances, T_e_(O^+2^) is smaller than T_e_(N^+^) and possibly T_e_(S^+^), the ionized mass is ~0.07 M_{sun}_ and the progenitor zero-age main-sequence mass is 1.2-2 M_{sun}_. If electrons are in equilibrium, recombination lines are likely produced in a cold low-density medium. A photoionization model (cloudy 13.03) with a positive density gradient and two exciting sources, reproduced most of the optical spectrum, the temperature distribution of the nebula, HeII 4686/HeI 5876, [OII]3726/[OIII]5007 and [OII]3726/3729, but not the other density sensitive line ratios. Including fluorescence and recombination, we found good agreement with observed CII and CIII line intensities, OII and OIII model intensities which are 2.6 and 7.8 times smaller than observed and large erratic differences with observations in CIII, NII and NIII lines. UV and IR data suggest that [OII] emission is from a region ~6 times less dense than assumed by the model and that IR lines are produced in a medium where the density is ~1000/cm^3^. There may be a lower density medium beyond a dense ring described by the photoionization model, as well as a cold low-density component. A multicomponent model is required to reproduce the entire spectrum of NGC 6210.
- ID:
- ivo://CDS.VizieR/J/A+A/578/A75
- Title:
- Spectrum of V4332 Sgr in 2005
- Short Name:
- J/A+A/578/A75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- V4332 Sgr is a red transient (red nova) whose eruption was observed in 1994. The remnant of the eruption shows a unique optical spectrum: strong emission lines of atomes and molecules superimposed on a M-type stellar spectrum. The stellar-like remnant is presumably embedded in a disc-like dusty envelope orientated almost face-on. The observed optical spectrum is supposed to result from interactions of the central-star radiation with dust and gas in the disc and outflows initiated in 1994. We have reduced and measured a high-resolution (R~40000) spectrum of V4332 Sgr obtained with VLT/UVES in April/May 2005. The spectrum comes from the ESO archives and is the best quality spectrum of the object ever obtained. We have identified and measured over 200 emission features belonging to 11 elements and 6 molecules. The continuous, stellar-like component can be classified as ~M3. The radial velocity of the object, as derived from narrow atomic emission line, is -75km/s. The interstellar reddening was estimated as being 0.35<E(B-V)<0.75. From radial velocities of interstellar absorption features in the NaI D lines we have estimated a lower limit of ~5.5 kpc to the distance of V4332 Sgr. When compared to spectroscopic observations done in 2009, the spectrum of V4332 Sgr considerably evolved between 2005 and 2009. The object significantly faded in the optical (by ~2mag in the V band), which resulted from the main remnant cooled by 300-350K corresponding to its spectral type changed from M3 to M5-6. The object however increased in luminosity by ~50%, implying a significant expansion of its dimensions. Most of the emission features seen in 2005 significantly faded or even disappeared from the spectrum of V4332 Sgr in 2009.
- ID:
- ivo://CDS.VizieR/J/ApJS/220/16
- Title:
- SpeX NIR survey of 886 nearby M dwarfs
- Short Name:
- J/ApJS/220/16
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of near-infrared (NIR) spectra and associated measurements for 886 nearby M dwarfs. The spectra were obtained with the NASA-Infrared Telescope Facility SpeX Spectrograph during a two-year observing campaign; they have high signal-to-noise ratios (S/N>100-150), span 0.8-2.4{mu}m, and have R~2000. Our catalog of measured values contains useful T_eff_ and composition-sensitive features, empirical stellar parameter measurements, and kinematic, photometric, and astrometric properties compiled from the literature. We focus on measurements of M dwarf abundances ([Fe/H] and [M/H]), capitalizing on the precision of recently published empirical NIR spectroscopic calibrations. We explore systematic differences between different abundance calibrations, and from other similar M dwarf catalogs. We confirm that the M dwarf abundances we measure show the expected inverse dependence with kinematic-, activity-, and color-based age indicators. Finally, we provide updated [Fe/H] and [M/H] for 16 M dwarf planet hosts. This catalog represents the largest published compilation of NIR spectra and associated parameters for M dwarfs. It provides a rich and uniform resource for nearby M dwarfs, and will be especially valuable for measuring Habitable Zone locations and comparative abundances of the M dwarf planet hosts that will be uncovered by upcoming exoplanet surveys.
- ID:
- ivo://CDS.VizieR/J/ApJ/710/1142
- Title:
- SpeX spectroscopy of low mass binaries. I.
- Short Name:
- J/ApJ/710/1142
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the identification of 17 candidate brown dwarf binaries whose components straddle the L dwarf/T dwarf transition. These sources were culled from a large near-infrared spectral sample of L and T dwarfs observed with the Infrared Telescope Facility SpeX spectrograph. Candidates were selected on the basis of spectral ratios which segregate known (resolved) L dwarf/T dwarf pairs from presumably single sources. Composite templates, constructed by combining 13581 pairs of absolute flux-calibrated spectra, are shown to provide statistically superior fits to the spectra of our 17 candidates as compared to single templates. Ten of these candidates appear to have secondary components that are significantly brighter than their primaries over the 1.0-1.3um band, indicative of rapid condensate depletion at the L dwarf/T dwarf transition. Our results support prior indications of enhanced multiplicity amongst early-type T dwarfs; 53+/-7% of the T0-T4 dwarfs in our spectral sample are found to be either resolved or unresolved (candidate) pairs, although this is consistent with an intrinsic (volume complete) brown dwarf binary fraction of only 15%. If verified, this sample of spectral binaries more than doubles the number of known L dwarf/T dwarf transition pairs, enabling a broader exploration of this poorly understood phase of brown dwarf atmospheric evolution.
- ID:
- ivo://CDS.VizieR/J/AJ/130/1037
- Title:
- Spiral galaxies rotation curve data
- Short Name:
- J/AJ/130/1037
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new long-slit H{alpha} spectroscopy for 403 non-interacting spiral galaxies, obtained at the Palomar Observatory 5m Hale telescope, which is used to derive well-sampled optical rotation curves. Because many of the galaxies show optical emission features that are significantly extended along the spectrograph slit, a technique was devised to separate and subtract the night sky lines from the galaxy emission. We exploit a functional fit to the rotation curve to identify its center of symmetry; this method minimizes the asymmetry in the final, folded rotation curve. We derive rotational widths using both velocity histograms and the Polyex model fit. The final rotational width is measured at a radius containing 83% of the total light as derived from I-band images.
- ID:
- ivo://CDS.VizieR/J/A+A/619/A50
- Title:
- Spiral potential of the Milky Way
- Short Name:
- J/A+A/619/A50
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The location of young sources in the Galaxy suggests a four-armed spiral structure, whereas tangential points of spiral arms observed in the integrated light at infrared and radio wavelengths indicate that only two arms are massive. Variable extinction in the Galactic plane and high light-to-mass ratios of young sources make it difficult to judge the total mass associated with the arms outlined by such tracers. The current objective is to estimate the mass associated with the Sagittarius arm by means of the kinematics of the stars across it. Spectra of 1726 candidate B- and A-type stars within 3{deg} of the Galactic center (GC) were obtained with the FLAMES instrument at the VLT with a resolution of ~6000 in the spectral range of 396-457nm. Radial velocities were derived by least-squares fits of the spectra to synthetic ones. The final sample was limited to 1507 stars with either Gaia DR2 parallaxes or main-sequence B-type stars having reliable spectroscopic distances. The solar peculiar motion in the direction of the GC relative to the local standard of rest (LSR) was estimated to U_{sun}_=10.7+/-1.3km/s. The variation in the median radial velocity relative to the LSR as a function of distance from the sun shows a gradual increase from slightly negative values near the sun to almost 5km/s at a distance of around 4kpc. A sinusoidal function with an amplitude of 3.4+/-1.3km/s and a maximum at 4.0+/-0.6kpc inside the sun is the best fit to the data. A positive median radial velocity relative to the LSR around 1.8kpc, the expected distance to the Sagittarius arm, can be excluded at a 99% level of confidence. A marginal peak detected at this distance may be associated with stellar streams in the star-forming regions, but it is too narrow to be associated with a major arm feature. A comparison with test-particle simulations in a fixed galactic potential with an imposed spiral pattern shows the best agreement with a two-armed spiral potential having the Scutum-Crux arm as the next major inner arm. A relative radial forcing dFr~1.5% and a pattern speed in the range of 20-30km/s/kpc yield the best fit. The lack of a positive velocity perturbation in the region around the Sagittarius arm excludes it from being a major arm. Thus, the main spiral potential of the Galaxy is two-armed, while the Sagittarius arm is an inter-arm feature with only a small mass perturbation associated with it.
2630. Spirals in Virgo. III.
- ID:
- ivo://CDS.VizieR/J/A+AS/110/279
- Title:
- Spirals in Virgo. III.
- Short Name:
- J/A+AS/110/279
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the analysis of the rotation curves of a sample of 32 spiral galaxies derived from the spectroscopic observations of a sample of 47 galaxies.
