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2171. 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.
2172. 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.
2173. MaNGA star-forming galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/508/1084
Title:
MaNGA star-forming galaxies
Short Name:
J/MNRAS/508/1084
Date:
19 Jan 2022 00:58:55
Publisher:
CDS
Description:
We investigate radiation hardness within a representative sample of 67 nearby (0.02<~z<~0.06) star-forming (SF) galaxies using the integral field spectroscopic data from the MaNGA survey. The softness parameter {eta}=(O^+^/O^2+^)/(S^+^/S^2+^) is sensitive to the spectral energy distribution of the ionizing radiation. We study {eta} via the observable quantity {eta}'(=([OII]/[OIII])/([SII][SIII])). We analyze the relation between radiation hardness (traced by {eta} and {eta}') and diagnostics sensitive to gas-phase metallicity, electron temperature, density, ionization parameter, effective temperature, and age of ionizing populations. It is evident that low metallicity is accompanied by low log{eta}', i.e. hard radiation field. No direct relation is found between radiation hardness and other nebular parameters though such relations cannot be ruled out. We provide empirical relations between log{eta} and strong emission line ratios N2, O3N2, and Ar3O3, which will allow future studies of radiation hardness in SF galaxies where weak auroral lines are undetected. We compare the variation of [OIII]/[OII] and [SIII]/[SII] for MaNGA data with SF galaxies and HII regions within spiral galaxies from literature and find that the similarity and differences between different data set are mainly due to the metallicity. We find that predictions from photoionization models considering young and evolved stellar populations as ionizing sources in good agreement with the MaNGA data. This comparison also suggests that hard radiation fields from hot and old low-mass stars within or around SF regions might significantly contribute to the observed {eta} values.
2174. Mapping the stellar age of the Milky Way
ID:
ivo://CDS.VizieR/J/A+A/629/A1
Title:
Mapping the stellar age of the Milky Way
Short Name:
J/A+A/629/A1
Date:
21 Oct 2021
Publisher:
CDS
Description:
The bulge represents the best compromise between old and massive Galactic component, and as such its study is a valuable opportunity to understand how the bulk of the Milky Way formed and evolved. In addition, being the only bulge in which we can individually resolve stars in all evolutionary sequences, the properties of its stellar content provide crucial insights on the formation of bulges at large. We aim at providing a detailed and comprehensive census of the Milky Way bulge stellar populations by producing deep and accurate photometric catalogs of the inner ~300 sqdeg of the Galaxy. We perform DAOPHOT/ALLFRAME PSF-fitting photometry of multi-epochs J and Ks images provided by the VVV survey to obtain deep photometric catalogs. Artificial star experiments have been conducted on all images to properly assess the completeness and the accuracy of the photometric measurements. We present a photometric database containing nearly 600 million stars across the bulge area surveyed by the VVV. Through the comparison of derived color-magnitude diagrams of selected fields representative of different levels of extinction and crowding, we show the quality, completeness and depth of the new catalogs. With the exception of the fields located along the plane, this new photometry samples stars down to ~1-2mag below the MS-TO with unprecedented accuracy. To demonstrate the tremendous potential inherent to this new dataset, we give few examples of possible applications such as: i) star counts studies through the dataset completeness map; ii) surface brightness map; and iii) cross-correlation with Gaia DR2. The database presented here represents an invaluable collection for the whole community, and we encourage its exploitation. The photometric catalogs including completeness information are publicly available through the ESO Science Archive.
2175. Maps of dust distribution in M31 bulge
ID:
ivo://CDS.VizieR/J/MNRAS/459/2262
Title:
Maps of dust distribution in M31 bulge
Short Name:
J/MNRAS/459/2262
Date:
21 Oct 2021
Publisher:
CDS
Description:
We map the dust distribution in the central 180" (~680pc) region of the M31 bulge, based on HST WFC3 and ACS observations in ten bands from near-ultraviolet (2700{AA}) to near-infrared (1.5-micron). This large wavelength coverage gives us great leverage to detect not only dense dusty clumps, but also diffuse dusty molecular gas. We fit a pixel-by-pixel spectral energy distributions to construct a high-dynamic-range extinction map with unparalleled angular resolution (~0.5", i.e., ~2pc) and sensitivity (the extinction uncertainty, delta A_V_~0.05). In particular, the data allow to directly fit the fractions of starlight obscured by individual dusty clumps, and hence their radial distances in the bulge. Most of these clumps seem to be located in a thin plane, which is tilted with respect to the M31 disk and appears face-on. We convert the extinction map into a dust mass surface density map and compare it with that derived from the dust emission as observed by Herschel. The dust masses in these two maps are consistent with each other, except in the low-extinction regions, where the mass inferred from the extinction tends to be underestimated. Further, we use simulations to show that our method can be used to measure the masses of dusty clumps in Virgo cluster early-type galaxies to an accuracy within a factor of ~2.
2176. MAPS-PP catalog of galaxies
ID:
ivo://CDS.VizieR/J/AJ/116/1094
Title:
MAPS-PP catalog of galaxies
Short Name:
J/AJ/116/1094
Date:
21 Oct 2021
Publisher:
CDS
Description:
A search for preferential galaxy alignments in the Pisces-Perseus Supercluster (PPS) is made using the Minnesota Automated Plate Scanner Pisces-Perseus Survey (MAPS-PP). The MAPS-PP is a catalog of ~1400 galaxies with a (roughly) isophotal diameter greater than 30" constructed from digitized scans of the blue and red plates of the Palomar Observatory Sky Survey covering the PPS. This is the largest sample of galaxies applied to a search of galaxy alignments in this supercluster, and it has been used in combination with previously published redshifts to construct the deepest PPS galaxy luminosity function to date. While previous studies have relied extensively on catalogs with visually estimated parameters for both sample selection and determination of galaxy orientation, the MAPS-PP uses selection criteria and measurements that are entirely machine and computer based. Therefore, it is not susceptible to some of the biases, such as the diameter inclination effect, known to exist in some other galaxy catalogs. The presence of anisotropic galaxy distributions is determined by use of the Kuiper statistic, a robust alternative to the chi^2 statistic more traditionally used in these studies.
2177. M82-A radio continuum and polarisation study I.
ID:
ivo://CDS.VizieR/J/A+A/555/A23
Title:
M82-A radio continuum and polarisation study I.
Short Name:
J/A+A/555/A23
Date:
21 Oct 2021
Publisher:
CDS
Description:
In order to study the cosmic ray propagation and determine the magnetic field strength and dominant loss processes in the nearby prototypical starbursting galaxy M82, a multi-frequency analysis at four radio wavelengths is presented. Archival data from the Westerbork Synthesis Radio Telescope (WSRT) was reduced and a new calibration technique introduced to reach the high dynamic ranges needed for the complex source morphology. These data were combined with archival Very Large Array (VLA) data, yielding total power maps at {lambda}3cm, {lambda}6cm, {lambda}22cm, and {lambda}92cm. The data show a confinement of the emission at wavelengths of {lambda}3/{lambda}6cm to the core region and a largely extended halo reaching up to 4kpc away from the galaxy midplane at wavelengths of {lambda}22/{lambda}92cm up to a sensitivity limit of 90uJy and 1.8mJy respectively indicating different physical processes in the core and halo regions. The results are used to calculate the magnetic field strength to 98uG in the core region and to 24uG in the halo regions. From the observation of ionisation losses, the filling factor of the ionised medium could be estimated to 2%. This leads to a revised view of the magnetic field distribution in the core region and the propagation processes from the core into the halo regions.
2178. Markarian galaxies and Zwicky clusters relations
ID:
ivo://CDS.VizieR/J/A+AS/65/349
Title:
Markarian galaxies and Zwicky clusters relations
Short Name:
J/A+AS/65/349
Date:
21 Oct 2021
Publisher:
CDS
Description:
In the same area covered by Markarian survey and CGCG, there are 1344 Markarian galaxies, of which 597 are positioned inside the contours of Zwicky clusters. Data on these galaxies and respective clusters are presented in different tables, according to whether they are galaxies which are members of clusters, or probable or possible members projection cases are considered separately.
2179. Mark III Catalog of Galaxy Peculiar Velocities
ID:
ivo://CDS.VizieR/VII/198
Title:
Mark III Catalog of Galaxy Peculiar Velocities
Short Name:
VII/198
Date:
21 Oct 2021
Publisher:
CDS
Description:
Tully-Fisher and Dn-sigma distances, radial velocities, and associated catalog and observational data for the spiral, irregular, and elliptical galaxies that comprise the Mark 3 catalog are given in 5 different kinds of tables for seven separate data sets. Users interested only in the resulting distances need use only the files listed in sections 3 (Grouped spiral distance files), 4 (Elliptical galaxy distance files), and 5 (Comparison of galaxy distances).
2180. 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).

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