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1211. Intermediate-mass T Tau stars spectra
ID:
ivo://CDS.VizieR/J/A+A/622/A72
Title:
Intermediate-mass T Tau stars spectra
Short Name:
J/A+A/622/A72
Date:
21 Oct 2021
Publisher:
CDS
Description:
The origin of the fossil magnetic fields detected in 5 to 10% of intermediate-mass main sequence stars is still highly debated. We want to bring observational constraints to a large population of intermediate-mass pre-main sequence (PMS) stars in order to test the theory that convective-dynamo fields generated during the PMS phases of stellar evolution can occasionally relax into fossil fields on the main sequence. Using distance estimations, photometric measurements, and spectropolarimetric data from HARPSpol and ESPaDOnS of 38 intermediate-mass PMS stars, we determined fundamental stellar parameters (T_eff_, L and vsini) and measured surface magnetic field characteristics (including detection limits for non-detections, and longitudinal fields and basic topologies for positive detections). Using PMS evolutionary models, we determined the mass, radius, and internal structure of these stars. We compared different PMS models to check that our determinations were not model- dependant. We then compared the magnetic characteristics of our sample accounting for their stellar parameters and internal structures. Results: We detect magnetic fields in about half of our sample. About 90% of the magnetic stars have outer convective envelopes larger than ~25% of the stellar radii, and heavier than ~2% of the stellar mass. Going to higher mass, we find that the magnetic incidence in intermediate-mass stars drops very quickly, within a time-scale of the order of few times 0.1Myr. Finally, we propose that intermediate-mass T Tauri stars with large convective envelopes, close to the fully convective limit, have complex fields and that their dipole component strengths may decrease as the sizes of their convective envelopes decrease, similar to lower-mass T Tauri stars.
1212. Interstellar Ca I absorption
ID:
ivo://CDS.VizieR/J/ApJS/147/61
Title:
Interstellar Ca I absorption
Short Name:
J/ApJS/147/61
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present high-resolution (FWHM~0.3-1.5km/s) spectra, obtained with the AAT UHRF, the McDonald Observatory 2.7m coude spectrograph, and/or the KPNO coude feed, of interstellar Ca I absorption toward 30 Galactic stars. Comparisons of the column densities of Ca I, Ca II, K I, and other species - for individual components identified in the line profiles and also when integrated over entire lines of sight - yield information on relative electron densities and depletions (dependent on assumptions regarding the ionization equilibrium).
1213. Interstellar lines catalogue
ID:
ivo://CDS.VizieR/III/148A
Title:
Interstellar lines catalogue
Short Name:
III/148A
Date:
21 Oct 2021
Publisher:
CDS
Description:
A bibliographical catalogue of the interstellar lines has been prepared (2003 stars in our Galaxy, 86 stars in the Magellanic Clouds and 41 extragalactic objects), and 371 bibliographical references.
1214. Interstellar NaI, TiII & CaIIK obs.
ID:
ivo://CDS.VizieR/J/MNRAS/367/1478
Title:
Interstellar NaI, TiII & CaIIK obs.
Short Name:
J/MNRAS/367/1478
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of interstellar NaI ({lambda}_air_=3302.37 and 3302.98{AA}), TiII ({lambda}_air_=3383.76{AA}) and CaIIK ({lambda}_air_=3933.66{AA}) absorption features for 74 sightlines towards O- and B-type stars in the Galactic disc. The data were obtained from the Ultraviolet and Visual Echelle Spectrograph Paranal Observatory Project (UVES POP), at a spectral resolution of 3.75km/s and with mean signal-to-noise ratios per pixel of 260, 300 and 430 for the NaI, TiII and CaII observations, respectively. Interstellar features were detected in all but one of the TiII sightlines and all of the CaII sightlines. The dependence of the column density of these three species with distance, height relative to the Galactic plane, HI column density, reddening and depletion relative to the solar abundance has been investigated. We also examine the accuracy of using the NaI column density as an indicator of that for HI. In general, we find similar strong correlations for both Ti and Ca, and weaker correlations for Na. Our results confirm the general belief that Ti and Ca occur in the same regions of the interstellar medium (ISM) and also that the TiII/CaII ratio is constant over all parameters. We hence conclude that the absorption properties of Ti and Ca are essentially constant under the general ISM conditions of the Galactic disc.
1215. Interstellar SiO sources
ID:
ivo://CDS.VizieR/J/A+AS/132/211
Title:
Interstellar SiO sources
Short Name:
J/A+AS/132/211
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results of a survey of SiO emission using the 15-m SEST and the 20-m Onsala telescope are presented in two tables. The sample contains altogether 369 objects including 270 H2O masers, 19 OH masers and 62 IRAS sources with colours typical for ultracompact HII regions. The remaining target sources consist of dust continuum peaks a CS emission peak near H2O masers (12) and Herbig-Haro objects (6). The entries are arranged according to increasing right ascension.
1216. INT near-Earth asteroids spectroscopic survey
ID:
ivo://CDS.VizieR/J/A+A/627/A124
Title:
INT near-Earth asteroids spectroscopic survey
Short Name:
J/A+A/627/A124
Date:
21 Oct 2021
Publisher:
CDS
Description:
The population of near-Earth asteroids (NEAs) shows a large variety of objects in terms of physical and dynamical properties. They are subject to planetary encounters and to strong solar wind and radiation effects. Their study is also motivated by practical reasons regarding space exploration and long-term probability of impact with the Earth. We aim to spectrally characterize a significant sample of NEAs with sizes in the range of ~0.25-5.5km (categorized as large), and search for connections between their spectral types and the orbital parameters. Optical spectra of NEAs were obtained using the Isaac Newton Telescope (INT) equipped with the IDS spectrograph. These observations are analyzed using taxonomic classification and by comparison with laboratory spectra of meteorites. A total number of 76 NEAs were observed. We spectrally classified 44 of them as Q/S-complex, 16 as B/C-complex, eight as V-types, and another eight belong to the remaining taxonomic classes. Our sample contains 27 asteroids categorized as potentially hazardous and 31 possible targets for space missions including (459872) 2014 EK24, (436724) 2011 UW158, and (67367) 2000 LY27. The spectral data corresponding to (276049) 2002 CE26 and (385186) 1994 AW1 shows the 0.7um feature which indicates the presence of hydrated minerals on their surface. We report that Q-types have the lowest perihelia (a median value and absolute deviation of 0.797+/-0.244AU) and are systematically larger than the S-type asteroids observed in our sample. We explain these observational evidences by thermal fatigue fragmentation as the main process for the rejuvenation of NEA surfaces. In general terms, the taxonomic distribution of our sample is similar to the previous studies and matches the broad groups of the inner main belt asteroids. Nevertheless, we found a wide diversity of spectra compared to the standard taxonomic types.
1217. Inversion of the HE 1122-1648 UVES spectrum
ID:
ivo://CDS.VizieR/J/A+A/376/28
Title:
Inversion of the HE 1122-1648 UVES spectrum
Short Name:
J/A+A/376/28
Date:
21 Oct 2021
Publisher:
CDS
Description:
File tablea1.dat contains the list of the Lyman-{alpha} absorption lines identified in the spectrum of HE 1122-1648 obtained during Science Verification of UVES at the VLT. We used the standard method of Voigt Profile fitting with VPFIT and with the inversion method described in the related paper. (Note that the printed version of the paper indicates HE 1122-1628, instead of the quasar HE 1122-1648).
1218. Investigating Tully-Fisher relation with KMOS^3D^
ID:
ivo://CDS.VizieR/J/ApJ/842/121
Title:
Investigating Tully-Fisher relation with KMOS^3D^
Short Name:
J/ApJ/842/121
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate the stellar mass and baryonic mass Tully-Fisher relations (TFRs) of massive star-forming disk galaxies at redshift z~2.3 and z~0.9 as part of the KMOS^3D^ integral field spectroscopy survey. Our spatially resolved data allow reliable modeling of individual galaxies, including the effect of pressure support on the inferred gravitational potential. At fixed circular velocity, we find higher baryonic masses and similar stellar masses at z~2.3 as compared to z~0.9. Together with the decreasing gas-to-stellar mass ratios with decreasing redshift, this implies that the contribution of dark matter to the dynamical mass on the galaxy scale increases toward lower redshift. A comparison to local relations reveals a negative evolution of the stellar and baryonic TFR zero points from z=0 to z~0.9, no evolution of the stellar TFR zero point from z~0.9 to z~2.3, and a positive evolution of the baryonic TFR zero point from z~0.9 to z~2.3. We discuss a toy model of disk galaxy evolution to explain the observed nonmonotonic TFR evolution, taking into account the empirically motivated redshift dependencies of galactic gas fractions and the relative amount of baryons to dark matter on galaxy and halo scales.
1219. Ion and femtosecond laser irradiation spectra
ID:
ivo://CDS.VizieR/J/A+A/654/A143
Title:
Ion and femtosecond laser irradiation spectra
Short Name:
J/A+A/654/A143
Date:
22 Feb 2022
Publisher:
CDS
Description:
Space weathering is a process that changes the surface of airless planetary bodies. Prime space weathering agents are solar wind irradiation and micrometeoroid bombardment. These processes alter planetary reflectance spectra and often modify their compositional diagnostic features. In this work we focused on simulating and comparing the spectral changes caused by solar wind irradiation and by micrometeoroid bombardment to gain a better understanding of these individual space weathering processes. We used olivine and pyroxene pellets as proxies for planetary materials. To simulate solar wind irradiation we used hydrogen, helium, and argon ions with energies from 5 to 40keV and fluences of up to 10^18^particles/cm^2^. To simulate micrometeoroid bombardment we used individual femtosecond laser pulses. We analysed the corresponding evolution of different spectral parameters, which we determined by applying the Modified Gaussian Model, and we also conducted principal component analysis. The original mineralogy of the surface influences the spectral evolution more than the weathering agent, as seen from the diverse evolution of the spectral slope of olivine and pyroxene upon irradiation. The spectral slope changes seen in olivine are consistent with observations of A-type asteroids, while the moderate to no slope changes observed in pyroxene are consistent with asteroid (4) Vesta. We also observed some differences in the spectral effects induced by the two weathering agents. Ions simulating solar wind have a smaller influence on longer wavelengths of the spectra than laser irradiation simulating micrometeoroid impacts. This is most likely due to the different penetration depths of ions and laser pulses. Our results suggest that in some instances it might be possible to distinguish between the contributions of the two agents on a weathered surface.
1220. Ionized gas in E/S0 galaxies with dust lanes
ID:
ivo://CDS.VizieR/J/MNRAS/407/2475
Title:
Ionized gas in E/S0 galaxies with dust lanes
Short Name:
J/MNRAS/407/2475
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the results of multicolour observations of 30 E/S0 galaxies with dust lanes. For each galaxy we obtained broad-band images and narrow-band images using interference filters isolating the H{alpha}+[NII] emission lines to derive the amount and morphology of dust and ionized gas. To improve the wavelength coverage we retrieved data from the Sloan Digital Sky Survey and Two Micron All Sky Survey and combined these with our data. Ionized gas is detected in 25 galaxies and shows in most cases a smooth morphology, although knots and filamentary structure are also observed in some objects.

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