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1531. Magnetic flaring from PMS stars spectra
ID:
ivo://CDS.VizieR/J/A+A/620/A55
Title:
Magnetic flaring from PMS stars spectra
Short Name:
J/A+A/620/A55
Date:
21 Oct 2021
Publisher:
CDS
Description:
Flares from the Sun and other stars are most prominently observed in the soft X-ray band. Most of the radiated energy, however, is released at optical/UV wavelengths. In spite of decades of investigation, the physics of flares is not fully understood. Even less is known about the powerful flares routinely observed from pre-main sequence stars, which might significantly influence the evolution of circumstellar disks. Observations of the NGC2264 star forming region were obtained in Dec. 2011, simultaneously with three telescopes, Chandra (X-rays), CoRoT (optical), and Spitzer (mIR), as part of the "Coordinated Synoptic Investigation of NGC2264" (CSI-NGC2264). Shorter Chandra and CoRoT observations were also obtained in March 2008. We analyzed the lightcurves to detect X-ray flares with an optical and/or mIR counterpart. Basic flare properties from the three datasets, such as emitted energies and peak luminosities, were then compared to constrain the spectral energy distribution of the flaring emission and the physical conditions of the emitting regions. Flares from stars with and without circumstellar disks were also compared to establish any difference that might be attributed to the presence of disks. Seventy-eight X-ray flares with an optical and/or mIR counterpart were detected. Their optical emission is found to correlate well with, and to be significantly larger than, the X-ray emission. The slopes of the correlations suggest that the difference becomes smaller for the most powerful flares. The mIR flare emission seems to be strongly affected by the presence of a circumstellar disk: flares from stars with disks have a stronger mIR emission with respect to stars without disks. This might be attributed to the reprocessing of the optical (and X-ray) flare emission by the inner circumstellar disk, providing evidence for flare-induced disk heating.
1532. Main-sequence star chromospheres
ID:
ivo://CDS.VizieR/J/MNRAS/403/2157
Title:
Main-sequence star chromospheres
Short Name:
J/MNRAS/403/2157
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on high-resolution observations of two dM1 stars: Gl 867A, an active dM1e star, and Gl 205, a less active dM1 star. The wavelength coverage is from 3890 to 6820{AA} with a resolving power of about 45000. The difference spectrum of these two stars allows us to make a survey of spectral lines sensitive to magnetic activity.
1533. MALT90 Catalogue
ID:
ivo://CDS.VizieR/J/other/PASA/33.30
Title:
MALT90 Catalogue
Short Name:
J/other/PASA/33.
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Millimetre Astronomy Legacy Team 90GHz survey aims to characterise the physical and chemical evolution of high-mass clumps. Recently completed, it mapped 90GHz line emission towards 3246 high-mass clumps identified from the ATLASGAL 870um Galactic plane survey. By utilising the broad frequency coverage of the Mopra telescope's spectrometer, maps in 16 different emission lines were simultaneously obtained. Here, we describe the first catalogue of the detected line emission, generated by Gaussian profile fitting to spectra extracted towards each clumps' 870um dust continuum peak. Synthetic spectra show that the catalogue has a completeness of >95%, a probability of a false-positive detection of <0.3%, and a relative uncertainty in the measured quantities of <20% over the range of detection criteria. The detection rates are highest for the (1-0) transitions of HCO^+^, HNC, N_2_H^+^, and HCN (~77-89%). Almost all clumps (~95%) are detected in at least one of the molecular transitions, just over half of the clumps (~53%) are detected in four or more of the transitions, while only one clump is detected in 13 transitions. We find several striking trends in the ensemble of properties for the different molecular transitions when plotted as a function of the clumps' evolutionary state as estimated from Spitzer mid-IR images, including (1) HNC is relatively brighter in colder, less evolved clumps than those that show active star formation, (2) N2H+ is relatively brighter in the earlier stages, (3) that the observed optical depth decreases as the clumps evolve, and (4) the optically thickest HCO^+^ emission shows a 'blue-red asymmetry' indicating overall collapse that monotonically decreases as the clumps evolve. This catalogue represents the largest compiled database of line emission towards high-mass clumps and is a valuable data set for detailed studies of these objects.
1534. M8 and Her 36 C_2_H and c-C_3_H_2_ data
ID:
ivo://CDS.VizieR/J/A+A/626/A28
Title:
M8 and Her 36 C_2_H and c-C_3_H_2_ data
Short Name:
J/A+A/626/A28
Date:
21 Oct 2021
Publisher:
CDS
Description:
Hydrocarbons are ubiquitous in the interstellar medium, but their formation is still not well understood, depending on the physical environment they are found in. Messier 8 (M8) is host to one of the brightest Hii regions and photodissociation regions (PDRs) in our galaxy. With the observed C_2_H and c-C_3_H_2_ data toward M8, we aim at obtaining their densities and abundances and to shed some light on their formation mechanism. Using the Atacama Pathfinder Experiment (APEX) 12m, and the Institut de Radioastronomie Millimetrique (IRAM) 30m telescopes, we performed a line survey toward Herschel 36 (Her 36), which is the main ionizing stellar system in M8, and an imaging survey within 1.3x1.3pc around Her 36 of various transitions of C_2_H and C_3_H_2_. We used both Local Thermodynamic Equilibrium (LTE) and non-LTE methods to determine the physical conditions of the emitting gas along with the column densities and abundances of the observed species, which we compared with (updated) gas phase photochemical PDR models. In order to examine the role of polycyclic aromatic hydrocarbons (PAHs) in the formation of small hydrocarbons and to investigate their association with the Hii region, the PDR and the molecular cloud, we compared archival Galactic Legacy Infrared Mid-Plane Survey Extraordinaire (GLIMPSE) 8{mu}m and the Spectral and Photometric Imaging Receiver (SPIRE) 250{mu}m continuum images with the C_2_H emission maps. We observed a total of three rotational transitions of C_2_H with their hyperfine structure components and four rotational transitions of C_3_H_2_ with ortho and para symmetries toward the HII region and the PDR of M8. Fragmentation of PAHs seems less likely to contribute to the formation of small hydrocarbons as the 8 m emission does not follow the distribution of C_2_H emission, which is more associated with the molecular cloud toward the north-west of Her 36. From the quantitative analysis, we obtained abundances of 10^-8 ^and 10^-9^ for C_2_H and c-C_3_H_2_ respectively, and volume densities of the hydrocarbon emitting gas in the range n(H_2_)~5x10^4^-5x10^6^cm^-3^. The observed column densities of C_2_H and c-C_3_H_2_ are reproduced reasonably well by our PDR models. This supports the idea that in high-UV flux PDRs, gas phase chemistry is sufficient to explain hydrocarbon abundances.
1535. Manganese abundances in GC & dSph galaxies
ID:
ivo://CDS.VizieR/J/ApJ/891/85
Title:
Manganese abundances in GC & dSph galaxies
Short Name:
J/ApJ/891/85
Date:
21 Oct 2021
Publisher:
CDS
Description:
Manganese abundances are sensitive probes of the progenitors of TypeIa supernovae (SNe Ia). In this work, we present a catalog of manganese abundances in dwarf spheroidal satellites of the Milky Way, measured using medium-resolution spectroscopy. Using a simple chemical evolution model, we infer the manganese yield of SNe Ia in the Sculptor dwarf spheroidal galaxy (dSph) and compare to theoretical yields. The sub-solar yield from SNIa ([Mn/Fe]_Ia_=-0.30_-0.03_^+0.03^ at [Fe/H]=-1.5dex, with negligible dependence on metallicity) implies that sub-Chandrasekhar-mass (sub-MCh) white dwarf progenitors are the dominant channel of SNe Ia at early times in this galaxy, although some fraction (>~20%) of M_Ch_ Type Ia or Type Iax SNe are still needed to produce the observed yield. First-order corrections for deviations from local thermodynamic equilibrium increase the inferred [Mn/Fe]_Ia_ by as much as ~0.3dex. However, our results also suggest that the nucleosynthetic source of SNe Ia may depend on environment. In particular, we find that dSphs with extended star formation histories (Leo I, Fornax dSphs) appear to have higher [Mn/Fe] at a given metallicity than galaxies with early bursts of star formation (Sculptor dSph), suggesting that M_Ch_ progenitors may become the dominant channel of SNe Ia at later times in a galaxy's chemical evolution.
1536. MaNGA; parameters of 668 galaxies
ID:
ivo://CDS.VizieR/J/ApJ/903/52
Title:
MaNGA; parameters of 668 galaxies
Short Name:
J/ApJ/903/52
Date:
15 Mar 2022
Publisher:
CDS
Description:
The search for new global scaling relations linking the physical properties of galaxies has a fundamental interest. Furthermore, their recovery from spatially resolved relations has been in the spotlight of integral field spectroscopy (IFS). In this study, we investigate the existence of global and local relations between stellar age (Age*) and gas-phase metallicity (Zg). To this aim, we analyze IFS data for a sample of 736 star-forming disk galaxies from the MaNGA survey. We report a positive correlation between the global Zg and D(4000) (an indicator of stellar age), with a slope that decreases with increasing galaxy mass. Locally, a similar trend is found when analyzing the Zg and D(4000) of the star-forming regions, as well as the residuals resulting from removing the radial gradients of both parameters. The local laws have systematically smaller slopes than the global one. We ascribe this difference to random errors that cause the true slope of the Age*-Zg relation to be systematically underestimated when performing a least-squares fitting. The explored relation is intimately linked with the already known relation between gas metallicity and star formation rate at fixed mass, both presenting a common physical origin.
1537. Mapping spectral line survey toward W51 in 3mm
ID:
ivo://CDS.VizieR/J/ApJ/845/116
Title:
Mapping spectral line survey toward W51 in 3mm
Short Name:
J/ApJ/845/116
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have conducted a mapping spectral line survey toward the Galactic giant molecular cloud W51 in the 3mm band with the Mopra 22m telescope in order to study an averaged chemical composition of the gas extended over a molecular-cloud scale in our Galaxy. We have observed the area of 25'x30', which corresponds to 39pcx47pc. The frequency ranges of the observation are 85.1-101.1GHz and 107.0-114.9GHz. In the spectrum spatially averaged over the observed area, spectral lines of 12 molecular species and 4 additional isotopologues are identified. An intensity pattern of the spatially averaged spectrum is found to be similar to that of the spiral arm in the external galaxy M51, indicating that these two sources have similar chemical compositions. The observed area has been classified into five subregions according to the integrated intensity of ^13^CO(J=1-0) (I_13CO_), and contributions of the fluxes of 11 molecular lines from each subregion to the averaged spectrum have been evaluated. For most of the molecular species, 50% or more of the flux comes from the subregions with I_13CO_ from 25 to 100K.km.s^-1^, which does not involve active star-forming regions. Therefore, the molecular-cloud-scale spectrum observed in the 3mm band hardly represents the chemical composition of star-forming cores, but mainly represents the chemical composition of an extended quiescent molecular gas. The present result constitutes a sound base for interpreting the spectra of external galaxies at a resolution of a molecular-cloud scale (~10pc) or larger.
1538. Mark 110 optical emission line spectrum
ID:
ivo://CDS.VizieR/J/A+A/475/487
Title:
Mark 110 optical emission line spectrum
Short Name:
J/A+A/475/487
Date:
21 Oct 2021
Publisher:
CDS
Description:
We analyse in detail the rich emission line spectrum of Mark 110 to determine the physical conditions in the nucleus of this object, a peculiar NLS1 without any detectable Fe II emission associated with the broad line region and with a {lambda}5007/H{beta} line ratio unusually large for a NLS1. We use 24 spectra obtained with the Marcario Low Resolution Spectrograph attached at the prime focus of the 9.2m Hobby-Eberly telescope at the McDonald observatory. We fitted the spectrum by identifying all the emission lines (about 220) detected in the wavelength range 4200-6900{AA} (at rest).
1539. Mars atmospheric profiles - From NOMAD/TGO
ID:
ivo://bira-iasb/nomad/q/epn_core
Title:
Mars atmospheric profiles - From NOMAD/TGO
Short Name:
nomad.epn_core
Date:
11 Oct 2024 00:52:36
Publisher:
Planetary Atmospheres Research Unit - Royal Belgian Institute for Space Aeronomy
Description:
Derived data from measurements of the NOMAD instrument on board ESA's Trace Gas Orbiter. For more info on NOMAD, see Vandaele et al. (2018) https://doi.org/10.1007/s11214-018-0517-2 Vertical profiles of CO2 density and temperature of the Martian atmosphere: See papers Trompet et al. (2023a,b) https://doi.org/10.1029/2022JE007277, https://doi.org/10.1029/2022JE007279. Vertical profiles of H2O density: see paper Aoki et al. (2022) https://doi.org/10.1029/2022JE007231. Vertical profiles of O3 density: see paper Piccialli et al. (2022) https://doi. org/10.1029/2022EA002429 Vertical profiles of aerosols: see paper Flimon et al. (in rev.)
1540. MASCARA-2 b (HD185603) light curves and spectra
ID:
ivo://CDS.VizieR/J/A+A/612/A57
Title:
MASCARA-2 b (HD185603) light curves and spectra
Short Name:
J/A+A/612/A57
Date:
21 Oct 2021
Publisher:
CDS
Description:
In this paper we present MASCARA-2 b, a hot Jupiter transiting the m_V_=7.6 A2 star HD 185603. Since early 2015, MASCARA has taken more than 1.6 million flux measurements of the star, corresponding to a total of almost 3000 hours of observations, revealing a periodic dimming in the flux with a depth of 1.3%. Photometric follow-up observations were performed with the NITES and IAC80 telescopes and spectroscopic measurements were obtained with the Hertzsprung SONG telescope. We find MASCARA-2 b orbits HD 185603 with a period of 3.474119^+0.000005^_-0.000006_ days at a distance of 0.057+/-0.006AU, has a radius of 1.83+/-0.07R_J_ and place a 99 % upper limit on the mass of <17M_J_. HD 185603 is a rapidly rotating early-type star with an effective temperature of 8980^+90^_-130_K and a mass and radius of 1.89^+0.06^_-0.05_M_sun_, 1.60+/-0.06R_sun_, respectively. Contrary to most other hot Jupiters transiting early-type stars, the projected planet orbital axis and stellar spin axis are found to be aligned with {lambda}=0.6+/-4{deg}. The brightness of the host star and the high equilibrium temperature, 2260+/-50K, of MASCARA-2 b make it a suitable target for atmospheric studies from the ground and space. Of particular interest is the detection of TiO, which has recently been detected in the similarly hot planets WASP-33 b and WASP-19 b.

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