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621. 2D stellar kinematics of Mrk 1216
ID:
ivo://CDS.VizieR/J/ApJ/835/208
Title:
2D stellar kinematics of Mrk 1216
Short Name:
J/ApJ/835/208
Date:
21 Oct 2021
Publisher:
CDS
Description:
Mrk 1216 is a nearby, early-type galaxy with a small effective radius of 2.8kpc and a large stellar velocity dispersion of 308km/s for its K-band luminosity of 1.4x10^11^L_{sun}_. Using integral field spectroscopy assisted by adaptive optics from Gemini North, we measure spatially resolved stellar kinematics within ~450pc of the galaxy nucleus. The galaxy exhibits regular rotation with velocities of +/-180km/s and a sharply peaked velocity dispersion profile that reaches 425km/s at the center. We fit axisymmetric, orbit-based dynamical models to the combination of these high angular resolution kinematics, large-scale kinematics extending to roughly three effective radii, and Hubble Space Telescope imaging, resulting in a constraint of the mass of the central black hole in Mrk 1216. After exploring several possible sources of systematics that commonly affect stellar-dynamical black hole mass measurements, we find a black hole mass of M_BH_=(4.9+/-1.7)x10^9^M_{sun}_ and an H-band stellar mass-to-light ratio of {Upsilon}_H_=1.3+/-0.4{Upsilon}_{sun}_ (1{sigma} uncertainties). Mrk 1216 is consistent with the local black hole mass-stellar velocity dispersion relation, but is a factor of ~5-10 larger than expectations from the black hole mass-bulge luminosity and black hole mass-bulge mass correlations when conservatively using the galaxy's total luminosity or stellar mass. This behavior is quite similar to the extensively studied compact galaxy NGC 1277. Resembling the z~2 quiescent galaxies, Mrk 1216 may be a passively evolved descendant, and perhaps reflects a previous era when galaxies contained over-massive black holes relative to their bulge luminosities/masses, and the growth of host galaxies had yet to catch up.
622. D-type symbiotic stars emission line fluxes
ID:
ivo://CDS.VizieR/J/A+A/333/658
Title:
D-type symbiotic stars emission line fluxes
Short Name:
J/A+A/333/658
Date:
21 Oct 2021
Publisher:
CDS
Description:
Observations of five D-type symbiotics are presented: three oxygen Mira (He2-38, H2-38 and H1-36) and two carbon Mira symbiotics (AS 210 and SS 38). The observations in the spectral range between 3200{AA} and 7400{AA} show the presence of several emission lines in various states of excitation. A line list is provided with their suggested identifications. Several parameters were derived for each object: interstellar reddening as determined from Balmer decrement and He II lines, temperature and electronic density, abundance ratios of Ne/O, Ar/O, Fe/Ne, N/O and He/H. We found nitrogen enrichment while for the other elements their abundances are compatible with solar, except iron which is depleted. We did not detect significant changes in the line and in the continuos spectra of the stars analyzed here, except for He2-38, which increased its degree of excitation compared to Allen's (1984PASAu...5..562N) catalogue.
623. Dust and gas physics of the GOALS sample
ID:
ivo://CDS.VizieR/J/ApJ/790/124
Title:
Dust and gas physics of the GOALS sample
Short Name:
J/ApJ/790/124
Date:
13 Dec 2021 06:47:30
Publisher:
CDS
Description:
The Great Observatories All-sky LIRG Survey (GOALS) is a comprehensive, multiwavelength study of luminous infrared galaxies (LIRGs) in the local universe. Here, we present the results of a multi-component, spectral decomposition analysis of the low-resolution mid-infrared (MIR) Spitzer Infrared Spectrograph spectra from 5-38 {mu}m of 244 LIRG nuclei. The detailed fits and high-quality spectra allow for characterization of the individual polycyclic aromatic hydrocarbon (PAH) features, warm molecular hydrogen emission, and optical depths for both silicate dust grains and water ices. We find that starbursting LIRGs, which make up the majority of the GOALS sample, are very consistent in their MIR properties (i.e., {tau}_9.7 {mu}m_, {tau}_ice_, neon line ratios, and PAH feature ratios). However, as their EQW_6.2 {mu}m_decreases, usually an indicator of an increasingly dominant active galactic nucleus (AGN), LIRGs cover a larger spread in these MIR parameters. The contribution from PAH emission to the total IR luminosity (L(PAH)/L(IR)) in LIRGs varies from 2%-29% and LIRGs prior to their first encounter show significantly higher L(PAH)/L(IR) ratios on average. We observe a correlation between the strength of the starburst (represented by IR8 = L_IR_/L_8 {mu}m_) and the PAH fraction at 8 {mu}m but no obvious link between IR8 and the 7.7 to 11.3 PAH ratio, suggesting that the fractional photodissociation region (PDR) emission, and not the overall grain properties, is associated with the rise in IR8 for galaxies off the starburst main sequence. We detect crystalline silicate features in ~6% of the sample but only in the most obscure sources (s_9.7 {mu}m_< -1.24). Ice absorption features are observed in ~11% (56%) of GOALS LIRGs (ULIRGs) in sources with a range of silicate depths. Most GOALS LIRGs have L(H_2_)/L(PAH) ratios elevated above those observed for normal star-forming galaxies and exhibit a trend for increasing L(H_2_)/L(PAH) ratio with increasing L(H_2_). While star formation appears to be the dominant process responsible for exciting the H_2_ in most of the GOALS galaxies, a subset of LIRGs (~10%) shows excess H_2_emission that is inconsistent with PDR models and may be excited by shocks or AGN-induced outflows.
624. Dust classification in Galactic PNe
ID:
ivo://CDS.VizieR/J/ApJ/753/172
Title:
Dust classification in Galactic PNe
Short Name:
J/ApJ/753/172
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the Spitzer/Infrared Spectrograph (IRS) spectra of 157 compact Galactic planetary nebulae (PNe). These young PNe provide insight on the effects of dust in early post-asymptotic giant branch evolution, before much of the dust is altered or destroyed by the hardening stellar radiation field. Most of the selected targets have PN-type IRS spectra, while a few turned out to be misclassified stars. We inspected the group properties of the PN spectra and classified them based on the different dust classes (featureless or F, carbon-rich dust or CRD, oxygen-rich dust or ORD, mixed-chemistry dust or MCD) and subclasses (aromatic and aliphatic, and crystalline and amorphous). All PNe are characterized by dust continuum and more than 80% of the sample shows solid-state features above the continuum, in contrast with the Magellanic Cloud sample where only ~40% of the entire sample displays solid-state features; this is an indication of the strong link between dust properties and metallicity.
625. Dust emission from unobscured AGN
ID:
ivo://CDS.VizieR/J/ApJ/697/182
Title:
Dust emission from unobscured AGN
Short Name:
J/ApJ/697/182
Date:
21 Oct 2021
Publisher:
CDS
Description:
We use mid-infrared (MIR) spectroscopy of unobscured active galactic nuclei (AGNs) to reveal their native dusty environments. We concentrate on Seyfert 1 galaxies, observing a sample of 31 with the Infrared Spectrograph aboard the Spitzer Space Telescope, and compare them with 21 higher luminosity quasar counterparts.
626. Dust models & IR spectroscopy obs. of AGB stars
ID:
ivo://CDS.VizieR/J/ApJ/866/L1
Title:
Dust models & IR spectroscopy obs. of AGB stars
Short Name:
J/ApJ/866/L1
Date:
21 Oct 2021
Publisher:
CDS
Description:
Many emission features remain unidentified in the infrared spectra of asymptotic giant branch (AGB) stars. In particular, features at ~11, 20, 28, and 32{mu}m have been noted in mid-infrared spectra of oxygen-rich AGB stars. Here, I present models of dust excess emission in 36 spectra of 24 AGB stars from the Short Wavelength Spectrometer on board the Infrared Space Observatory and the Infrared Spectrograph on the Spitzer Space Telescope. The models include opacities of grains composed of mixtures of various polymorphs of alumina obtained by preparing bayerite and boehmite at high temperatures, and these dust components provide satisfactory fits to the 11, 20, 28, and 32{mu}m features. Though not a direct conclusion from this study, the presence of grains of the various polymorphs of aluminas in circumstellar dust shells around AGB stars suggests that corundum may have a role in giving rise to the 13{mu}m feature.
627. DustPedia metallicities and HI masses
ID:
ivo://CDS.VizieR/J/A+A/623/A5
Title:
DustPedia metallicities and HI masses
Short Name:
J/A+A/623/A5
Date:
21 Oct 2021
Publisher:
CDS
Description:
Observations of evolution in the dust-to-metal ratio allow to constrain the dominant dust processing mechanisms. In this work, we present a study of the dust-to-metal and dust-to-gas ratios in a subsample of ~500 DustPedia galaxies. Using literature and MUSE emission line fluxes, we derive gas-phase metallicities (oxygen abundances) for over 10000 individual regions and determine characteristic metallicities for each galaxy. We study how the relative dust, gas and metal contents of galaxies evolve by using metallicity and gas fraction as proxies for evolutionary state. The global oxygen abundance and nitrogen-to-oxygen ratio are found to increase monotonically as galaxies evolve. Additionally, unevolved galaxies (gas fraction >60%, metallicity 12+log(O/H)<8.2) have dust-to-metal ratios that are about a factor of 2.1 lower (factor of 6 lower for galaxies with gas fraction >80%) than the typical dust-to-metal ratio (Md/MZ~0.214) for more evolved sources. However, for high gas fractions, the scatter is larger due to larger observational uncertainties as well as a potential dependence of the dust grain growth timescale and supernova dust yield on local conditions and star formation histories. We find chemical evolution models with a strong contribution from dust grain growth describe these observations reasonably well. The dust-to-metal ratio is also found to be lower for low stellar masses and high specific star formation rates (with the exception of some sources undergoing a starburst). Finally, the metallicity gradient correlates weakly with the HI-to-stellar mass ratio, the effective radius and the dust-to-stellar mass ratio, but not with stellar mass.
628. DX Eri variability
ID:
ivo://CDS.VizieR/J/A+A/309/787
Title:
DX Eri variability
Short Name:
J/A+A/309/787
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of nearly simultaneous monitoring of uvby light and HeI667.81nm line-profile variations of the equatorial Be star DX Eri in November 1991. They are analysed along with numerous uvby photometry in the period 1986-1995.
629. Dynamical masses of z~2 quiescent galaxies
ID:
ivo://CDS.VizieR/J/ApJ/771/85
Title:
Dynamical masses of z~2 quiescent galaxies
Short Name:
J/ApJ/771/85
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using stellar kinematics measurements, we investigate the growth of massive, quiescent galaxies from z~2 to today. We present X-Shooter spectra from the UV to NIR and dynamical mass measurements of five quiescent massive (>10^11^M_{sun}_) galaxies at z~2. This triples the sample of z>1.5 galaxies with well-constrained ({delta}{sigma}<100km/s) velocity dispersion measurements. From spectral population synthesis modeling we find that these galaxies have stellar ages that range from 0.5 to 2Gyr, with no signs of ongoing star formation. We measure velocity dispersions (290-450km/s) from stellar absorption lines and find that they are 1.6-2.1 times higher than those of galaxies in the Sloan Digital Sky Survey at the same mass. Sizes are measured using GALFIT from Hubble Space Telescope Wide Field Camera 3 H_160_ and UDS K-band images. The dynamical masses correspond well to the spectral energy distribution based stellar masses, with dynamical masses that are ~15% higher.
630. Dynamical modelling of 4 early-type galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/363/769
Title:
Dynamical modelling of 4 early-type galaxies
Short Name:
J/MNRAS/363/769
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyse long-slit spectra of four early-type galaxies which extend from ~1 to 3 effective radii: IC 1459; IC 3370; NGC 3379 and NGC 4105. We have extracted the full line-of-sight velocity distribution (in the case of NGC 3379 we also used data from the literature), which we model using the two-integral approach. Using two-integral modelling, we find no strong evidence for dark haloes, but the fits suggest that three-integral modelling is necessary. We also find that the inferred constant mass-to-light ratio in all the four cases is typical for early-type galaxies. Finally, we also discuss the constraints on the mass-to-light ratio, which can be obtained using X-ray haloes in the case of IC 1459, NGC 3379 and NGC 4105, and compare the estimated values with the predictions from the dynamical modelling.

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