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1731. Nearby early-type gal. with ionized gas. II.
ID:
ivo://CDS.VizieR/J/A+A/445/79
Title:
Nearby early-type gal. with ionized gas. II.
Short Name:
J/A+A/445/79
Date:
21 Oct 2021
Publisher:
CDS
Description:
Rampazzo et al., 2005, Cat. <J/A+A/433/497> (Paper I) presented a data-set of line-strength indices for 50 early-type galaxies in the nearby Universe. The galaxy sample is biased toward galaxies showing emission lines, located in environments corresponding to a broad range of local galaxy densities, although predominantly in low density environments. The present addendum enlarges the above data-set of line-strength indices by analyzing 18 additional early-type galaxies (three galaxies, NGC 3607, NGC 5077 and NGC 5898 were presented in the previous set). We measured 25 line-strength indices, defined by the Lick IDS "standard" system (Trager et al., 1998, Cat. <J/ApJS/116/1>; Worthey & Ottaviani, 1997, Cat. <J/ApJS/111/377>), for 7 luminosity weighted apertures and 4 gradients of each galaxy. This addendum presents the line-strength data-set and compares it with the available data in the literature.
1732. Nearby galaxies abundances
ID:
ivo://CDS.VizieR/J/MNRAS/471/1743
Title:
Nearby galaxies abundances
Short Name:
J/MNRAS/471/1743
Date:
21 Oct 2021
Publisher:
CDS
Description:
We combine samples of nearby galaxies with Herschel photometry selected on their dust, metal, HI and stellar mass content, and compare these to chemical evolution models in order to discriminate between different dust sources. In a companion paper, we used an HI-selected sample of nearby galaxies to reveal a subsample of very gas-rich (gas fraction >80 per cent) sources with dust masses significantly below predictions from simple chemical evolution models, and well below M_d_/M_*_ and M_d_/M_gas_ scaling relations seen in dust and stellar-selected samples of local galaxies. We use a chemical evolution model to explain these dust-poor, but gas-rich, sources as well as the observed star formation rates (SFRs) and dust-to-gas ratios. We find that (i) a delayed star formation history is required to model the observed SFRs; (ii) inflows and outflows are required to model the observed metallicities at low gas fractions; (iii) a reduced contribution of dust from supernovae (SNe) is needed to explain the dust-poor sources with high gas fractions. These dust-poor, low stellar mass galaxies require a typical core-collapse SN to produce 0.01-0.16M_{sun}_ of dust. To match the observed dust masses at lower gas fractions, significant grain growth is required to counteract the reduced contribution from dust in SNe and dust destruction from SN shocks. These findings are statistically robust, though due to intrinsic scatter it is not always possible to find one single model that successfully describes all the data. We also show that the dust-to-metal ratio decreases towards lower metallicity.
1733. 4 nearby galaxies velocities & line-strengths
ID:
ivo://CDS.VizieR/J/A+A/428/877
Title:
4 nearby galaxies velocities & line-strengths
Short Name:
J/A+A/428/877
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present observations of four nearby early-type galaxies previously known (Rest et al., 2001AJ....121.2431R) to have nuclear stellar disks using two instruments on-board the Hubble Space Telescope. We observed NGC 4128, NGC 4612, and NGC 5308 with the Wide Field Planetary Camera 2, and the same three galaxies, plus NGC 4570, with the Space Telescope Imaging Spectrograph. We have detected a red nucleus in NGC 4128, a blue nucleus in NGC 4621, and a blue disk in NGC 5308. Additionally, we have discovered a blue disk-like feature with position angle ~15{deg} from the major axis in NGC 4621. In NGC 5308 there is evidence for a blue region along the minor axis. We discovered a blue transient on the images of NGC 4128 at position 0.14" west and 0.32" north from the nucleus. The extracted kinematic profiles belong to two groups: fast (NGC 4570 and NGC 5308) and kinematically disturbed rotators (NGC 4128 and NGC 4621). We report the discovery of a kinematically decoupled core in NGC 4128. Galaxies have mostly old (10-14Gyr) stellar populations with large spread in metallicities (sub- to super-solar). We discuss the possible formation scenarios, including bar-driven secular evolution and the influence of mergers, which can explain the observed color and kinematic features.
1734. Nearby galaxy filaments with UV obs.
ID:
ivo://CDS.VizieR/J/ApJ/814/40
Title:
Nearby galaxy filaments with UV obs.
Short Name:
J/ApJ/814/40
Date:
21 Oct 2021
Publisher:
CDS
Description:
Simulations of the formation of large-scale structures predict that dark matter, low density highly ionized gas, and galaxies form 10 to 40Mpc scale filaments. These structures are easily recognized in the distribution of galaxies. Here we use Ly{alpha} absorption lines to study the gas in 30x6Mpc filament at cz~3500km/s, defined using a new catalog of nearby (cz<10000km/s) galaxies, which is complete down to a luminosity of about 0.05L_*_ for the region of space analyzed here. Using Hubble Space Telescope spectra of 24 active galactic nuclei, we sample the gas in this filament. All of our sightlines pass outside the virial radius of any known filament galaxy. Within 500kpc of the filament axis the detection rate is ~80%, but no detections are seen more than 2.1Mpc from the filament axis. The width of the Ly{alpha} lines correlates with filament impact parameter and the four BLAs in our sample occur within 400kpc of the filament axis, indicating increased temperature and/or turbulence. Comparing to simulations, we find that the recent Haardt & Madau extragalactic ionizing background predicts a factor of 3-5 too few ionizing photons. Using a more intense radiation field matches the hydrogen density profile within 2.1Mpc of the filament axis, but the simulations still overpredict the detection rate between 2.1 and 5Mpc from the axis. The baryonic mass inside filament galaxies is 1.4x10^13^M_{sun}_, while the mass of filament gas outside galaxy halos is found to be 5.2x10^13^M_{sun}_.
1735. Nearby Ly{alpha} quasar absorbers
ID:
ivo://CDS.VizieR/J/ApJ/524/536
Title:
Nearby Ly{alpha} quasar absorbers
Short Name:
J/ApJ/524/536
Date:
21 Oct 2021
Publisher:
CDS
Description:
Spectroscopy of 10 quasars obtained with the Goddard High Resolution Spectrograph (GHRS) of the Hubble Space Telescope (HST) is presented. In the 10 sight lines, we detect 357 absorption lines above a significance level of 3{sigma} and 272 lines above a significance level of 4.5{sigma}. Automated software is used to detect and identify the lines, almost all of which are unresolved at the GHRS G140L resolution of 200km/s. After identifying Galactic lines, intervening metal lines, and higher order Lyman lines, we are left with 139 Ly{alpha} absorbers in the redshift range 0<z<0.22 (lines within 900km/s of geocoronal Ly{alpha} are not selected). These diffuse hydrogen absorbers have column densities that are mostly in the range 10^13^-10^15^cm^-2^ for an assumed Doppler parameter of 30km/s. The number density of lines above a rest equivalent width of 0.24{AA}, dN/dz=38.3{+/-}5.3, agrees well with the measurement from the Quasar Absorption-Line Key Project. There is marginal evidence for cosmic variance in the number of absorbers detected among the 10 sight lines.
1736. Near-Earth Object Survey (MANOS) spectroscopy
ID:
ivo://CDS.VizieR/J/AJ/158/196
Title:
Near-Earth Object Survey (MANOS) spectroscopy
Short Name:
J/AJ/158/196
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Mission Accessible Near-Earth Object Survey (MANOS) aims to observe and characterize small (mean absolute magnitude H~25 mag) Near-Earth Objects (NEOs) that are accessible by spacecraft (mean {Delta}~5.7 km/s) and that make close approaches with the Earth (mean Minimum Orbital Intersection Distance MOID ~0.03 au). We present here the first results of the MANOS visible spectroscopic survey. The spectra were obtained from August 2013 to March 2018 at Lowell Observatory's Discovery Channel 4.3 m telescope, and both Gemini North and South facilities. In total, 210 NEOs have been observed and taxonomically classified. Our taxonomic distribution shows significant variations with respect to surveys of larger objects. We suspect these to be due to a dependence of Main Belt source regions on object size. Compared to previous surveys of larger objects, we report a lower fraction of S+Q-complex asteroids of 43.8+/-4.6%. We associate this decrease with a lack of Phocaea family members at very small size. We also report higher fractions of X-complex and A-type asteroids of 23.8+/-3.3% and 3.8+/-1.3% respectively due to an increase of Hungaria family objects at small size. We find a strong correlation between the Q/S ratio and perihelion distance. We suggest this correlation is due to planetary close encounters with Venus playing a major role in turning asteroids from S to Q-type. This hypothesis is supported by a similar correlation between the Q/S ratio and Venus MOID.
1737. Nearest stars until 10pc
ID:
ivo://CDS.VizieR/V/101
Title:
Nearest stars until 10pc
Short Name:
V/101
Date:
21 Oct 2021
Publisher:
CDS
Description:
The given catalogue is a revised version of the catalogue (Zakhozhaj, 1987). The previous numeration is preserved, and the stars, with trigonometric, photometric and spectral parallaxes >0.100" are presented. The catalogue contains data on new components of multiple visual systems, on the components of spectral-binary systems, on invisible components with masses >0.08 solar mass. New data are obtained in 90s and contained in the articles [2-6]. The catalogue contains the main characteristics of stars such as the positions, proper motions, radial velocities, parallaxes, photometrical data and also new data of masses and radii of stars. The completeness of the catalogue is about 70%.
1738. Near-infrared hydrogen & helium QSO emission lines
ID:
ivo://CDS.VizieR/J/AJ/158/129
Title:
Near-infrared hydrogen & helium QSO emission lines
Short Name:
J/AJ/158/129
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present 14 near-infrared (NIR) quasar spectra observed with the Flamingos-2 NIR spectrometer instrument at the Gemini South Observatory. The targets were selected with redshifts of (0.58~<z~<0.63) to ensure the spectral wavelength range included specifically identified hydrogen and helium broad emission lines. We present measurements of their FWHM, equivalent widths, and flux ratios relative to H{alpha}. The quasars are all within the Sloan Digital Sky Survey (SDSS) Stripe 82 region which, then also provides multi-epoch rest-frame UV and optical spectroscopic observations of our targets. In future work, these data and those from Galaxy Evolution Explorer and NUV spectra will be utilized to constrain photoionization models to determine physical conditions within the broad emission line regions, such as the incident ionizing photon flux and gas density.
1739. Near-infrared spectra for TW Hya
ID:
ivo://CDS.VizieR/J/A+A/642/L15
Title:
Near-infrared spectra for TW Hya
Short Name:
J/A+A/642/L15
Date:
21 Oct 2021
Publisher:
CDS
Description:
Volatile molecules are critical to terrestrial planetary habitability, yet they are difficult to observe directly where planets form at the midplanes of protoplanetary disks. It is unclear whether the inner ~1AU of disks are volatile-poor or if this region is resupplied with ice-rich dust from colder disk regions. Dust traps at radial pressure maxima bounding disk gaps can cut off the inner disk from these types of volatile reservoirs. However, the trap retention efficiency and atomic composition of trapped dust have not been measured. We present a new technique to measure the absolute atomic abundances in the gas accreting onto T Tauri stars and infer the bulk atomic composition and distribution of midplane solids that have been retained in the disk around the young star TW Hya. We identify near-infrared atomic line emission from gas-phase material inside the dust sublimation rim of TW Hya. Gaussian decomposition of the strongest H Paschen lines isolates the inner disk hydrogen emission. We measure several key elemental abundances, relative to hydrogen, using a chemical photoionization model and infer dust retention in the disk. With a 1D transport model, we determine approximate radial locations and retention efficiencies of dust traps for different elements. Volatile and refractory elements are depleted from TW Hya's hot gas by factors of ~10^2^ and up to 10^5^, respectively. The abundances of the trapped solids are consistent with a combination of primitive Solar System bodies. Dust traps beyond the CO and N_2_ snow line cumulatively sequester 96% of the total dust flux, while the trap at 2AU, near the H_2_O snow line, retains 3%. The high depletions of Si, Mg, and Ca are explained by a third trap at 0.3AU with >95% dust retention. TW Hya sports a significant volatile reservoir rich in C- and N-ices in its outer submillimeter ring structure. However, unless the inner disk was enhanced in C by earlier radial transport, typical C destruction mechanisms and the lack of a C resupply should leave the terrestrial planet-forming region of TW Hya "dry" and carbon-poor. Any planets that form within the silicate dust trap at 0.3 AU could resemble Earth in terms of the degree of their volatile depletion.
1740. Near-Infrared Spectra of IC5117
ID:
ivo://CDS.VizieR/J/AJ/121/362
Title:
Near-Infrared Spectra of IC5117
Short Name:
J/AJ/121/362
Date:
21 Oct 2021
Publisher:
CDS
Description:
Infrared spectroscopy from 0.8 to 2.5{mu}m is presented for the planetary nebula IC5117. The emission lines of IC5117 span a wide range of ionization that includes He II, [S III], [S II], [N I], and H2. The reddening measured from the hydrogen lines is E(B-V)=0.79, most of which is probably interstellar in origin. The He/H abundance ratio is 0.113+/-0.015, with approximately 10% of the helium being doubly ionized. Using our measurements of [S II] and [S III] lines and published observations of [S IV], we find a sulfur abundance, relative to hydrogen, of N(S)/N(H)=7.8 x 10^-6^, or approximately half the solar value. Fluxes and flux limits for several lines of molecular hydrogen are presented. Measurements of 1-0 transitions, together with the limits on 2-1 transitions, indicate Tvib~Trot=1900K, suggesting a purely collisional excitation mechanism. The ortho-to-para ratio is ~3, a value that is also indicative of collisional excitation. The presence of [C I] {lambda}9850 is consistent with previous studies of IC 5117 that indicated carbon is more abundant than oxygen. IC5117 follows the trend of planetary nebulae that display bipolar outflows and H2 emission to be carbon-rich. We confirm the results of Zhang & Kwok, who reported infrared continuum emission substantially in excess of that produced by the ionized gas. This emission is most likely due to hot dust (T~1300K) and accounts for roughly half of the continuum between 1.5 and 2{mu}m.

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