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- ID:
- ivo://CDS.VizieR/J/MNRAS/481/566
- Title:
- Properties of 333 SNe and their 269 hosts
- Short Name:
- J/MNRAS/481/566
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of the impact of spiral density waves (DWs) on the radial and surface density distributions of supernovae (SNe) in host galaxies with different arm classes. We use a well-defined sample of 269 relatively nearby, low-inclination, morphologically non-disturbed and unbarred Sa-Sc galaxies from the Sloan Digital Sky Survey, hosting 333 SNe. Only for core-collapse (CC) SNe, a significant difference appears when comparing their R_25_-normalized radial distributions in long-armed grand-design (LGD) versus non-GD (NGD) hosts, with that in LGD galaxies being marginally inconsistent with an exponential profile, while SNe Ia exhibit exponential surface density profiles regardless of the arm class. Using a smaller sample of LGD galaxies with estimated corotation radii (R_C_), we show that the R_C_-normalized surface density distribution of CC SNe indicates a dip at corotation. Although not statistically significant, the high CC SNe surface density just inside and outside corotation may be the sign of triggered massive star formation by the DWs. Our results may, if confirmed with larger samples, support the large-scale shock scenario induced by spiral DWs in LGD galaxies, which predicts a higher star formation efficiency around the shock fronts, avoiding the corotation region.
- ID:
- ivo://CDS.VizieR/J/MNRAS/471/1390
- Title:
- Properties of 102 SNe and their 100 hosts
- Short Name:
- J/MNRAS/471/1390
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of the height distributions of the different types of supernovae (SNe) from the plane of their host galaxies. We use a well-defined sample of 102 nearby SNe appearing inside high-inclined (i>=85{deg}), morphologically non-disturbed S0-Sd host galaxies from the Sloan Digital Sky Survey. For the first time, we show that in all the subsamples of spirals, the vertical distribution of core-collapse (CC) SNe is about twice closer to the plane of the host disc than the distribution of SNe Ia. In Sb-Sc hosts, the exponential scale height of CC SNe is consistent with those of the younger stellar population in the Milky Way (MW) thin disc, while the scale height of SNe Ia is consistent with those of the old population in the MW thick disc. We show that the ratio of scale lengths to scale heights of the distribution of CC SNe is consistent with those of the resolved young stars with ages from ~10 up to ~100Myr in nearby edge-on galaxies and the unresolved stellar population of extragalactic thin discs. The corresponding ratio for SNe Ia is consistent with the same ratios of the two populations of resolved stars with ages from a few 100Myr up to a few Gyr and from a few Gyr up to ~10Gyr, as well as with the unresolved population of the thick disc. These results can be explained considering the age-scale height relation of the distribution of stellar population and the mean age difference between Type Ia and CC SNe progenitors.
- ID:
- ivo://CDS.VizieR/J/MNRAS/456/2848
- Title:
- Properties of 500 SNe and their 419 hosts
- Short Name:
- J/MNRAS/456/2848
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of the impact of bars and bulges on the radial distributions of the different types of supernovae (SNe) in the stellar discs of host galaxies with various morphologies. We use a well-defined sample of 500 nearby (<=100Mpc) SNe and their low-inclined (i<=60deg) and morphologically non-disturbed S0-Sm host galaxies from the Sloan Digital Sky Survey. We find that in Sa-Sm galaxies, all core-collapse (CC) and vast majority of SNe Ia belong to the disc, rather than the bulge component. The radial distribution of SNe Ia in S0-S0/a galaxies is inconsistent with their distribution in Sa-Sm hosts, which is probably due to the contribution of the outer bulge SNe Ia in S0-S0/a galaxies. In Sa-Sbc galaxies, the radial distribution of CC SNe in barred hosts is inconsistent with that in unbarred ones, while the distributions of SNe Ia are not significantly different. At the same time, the radial distributions of both types of SNe in Sc-Sm galaxies are not affected by bars. We propose that the additional mechanism shaping the distributions of Type Ia and CC SNe can be explained within the framework of substantial suppression of massive star formation in the radial range swept by strong bars, particularly in early-type spirals. The radial distribution of CC SNe in unbarred Sa-Sbc galaxies is more centrally peaked and inconsistent with that in unbarred Sc-Sm hosts, while the distribution of SNe Ia in unbarred galaxies is not affected by host morphology. These results can be explained by the distinct distributions of massive stars in the discs of early- and late-type spirals.
- ID:
- ivo://CDS.VizieR/J/A+A/607/A81
- Title:
- Properties of the sample of clusters
- Short Name:
- J/A+A/607/A81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The relation between a cosmological halo concentration and its mass (cMr) is a powerful tool to constrain cosmological models of halo formation and evolution. On the scale of galaxy clusters the cMr has so far been determined mostly with X-ray and gravitational lensing data. The use of independent techniques is helpful in assessing possible systematics. Here we provide one of the few determinations of the cMr by the dynamical analysis of the projected-phase-space distribution of cluster members. Based on the WINGS and OmegaWINGS data sets, we used the Jeans analysis with the MAMPOSSt technique to determine masses and concentrations for 49 nearby clusters, each of which has >~60 spectroscopic members within the virial region, after removal of substructures. Our cMr is in statistical agreement with theoretical predictions based on {LAMBDA}CDM cosmological simulations. Our cMr is different from most previous observational determinations because of its flatter slope and lower normalization. It is however in agreement with two recent cMr obtained using the lensing technique on the CLASH and LoCuSS cluster data sets. The dynamical study of the projected-phase-space of cluster members is an independent and valid technique to determine the cMr of galaxy clusters. Our cMr shows no tension with theoretical predictions from {LAMBDA}CDM cosmological simulations for low-redshift, massive galaxy clusters. In the future we will extend our analysis to galaxy systems of lower mass and at higher redshifts.
- ID:
- ivo://CDS.VizieR/J/AJ/157/144
- Title:
- Protoplanetary disk masses in Taurus
- Short Name:
- J/AJ/157/144
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Measuring the masses of protoplanetary disks is crucial for understanding their planet-forming potential. Typically, dust masses are derived from (sub-)millimeter flux density measurements plus assumptions for the opacity, temperature, and optical depth of the dust. Here we use radiative transfer models to quantify the validity of these assumptions with the aim of improving the accuracy of disk dust mass measurements. We first carry out a controlled exploration of disk parameter space. We find that the disk temperature is a strong function of disk size, while the optical depth depends on both disk size and dust mass. The millimeter-wavelength spectral index can be significantly shallower than the naive expectation due to a combination of optical depth and deviations from the Rayleigh-Jeans regime. We fit radiative transfer models to the spectral energy distributions (SEDs) of 132 disks in the Taurus-Auriga region using a Markov chain Monte Carlo approach. We used all available data to produce the most complete SEDs used in any extant modeling study. We perform the fitting twice: first with unconstrained disk sizes and again imposing the disk size-brightness relation inferred for sources in Taurus. This constraint generally forces the disks to be smaller, warmer, and more optically thick. From both sets of fits, we find disks to be ~1-5 times more massive than when derived using (sub-)millimeter measurements and common assumptions. With the uncertainties derived from our model fitting, the previously measured dust mass-stellar mass correlation is present in our study but only significant at the 2{sigma} level.
497. (16) Psyche images
- ID:
- ivo://CDS.VizieR/J/A+A/619/L3
- Title:
- (16) Psyche images
- Short Name:
- J/A+A/619/L3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Asteroid (16) Psyche is the target of the NASA Psyche mission. It is considered one of the few main-belt bodies that could be an exposed proto-planetary metallic core and that would thus be related to iron meteorites. Such an association is however challenged by both its near- and mid-infrared spectral properties and the reported estimates of its density. Here, we aim to refine the density of (16) Psyche to set further constraints on its bulk composition and determine its potential meteoritic analog. We observed (16) Psyche with ESO VLT/SPHERE/ZIMPOL as part of our large program (ID 199.C-0074). We used the high angular resolution of these observations to refine Psyche's three-dimensional (3D) shape model and subsequently its density when combined with the most recent mass estimates. In addition, we searched for potential companions around the asteroid. We derived a bulk density of 3.99+/-0.26g/cm^3^ for Psyche. While such density is incompatible at the 3-sigma level with any iron meteorites (~7.8g/cm^3^), it appears fully consistent with that of stony-iron meteorites such as mesosiderites (density ~4.25g/cm^3^). In addition, we found no satellite in our images and set an upper limit on the diameter of any non-detected satellite of 1460+/-200m at 150km from Psyche (0.2%xR_Hill_, the Hill radius) and 800+/-200m at 2000km (3%xRHill). Considering that the visible and near-infrared spectral properties of mesosiderites are similar to those of Psyche, there is merit to a long-published initial hypothesis that Psyche could be a plausible candidate parent body for mesosiderites.
- ID:
- ivo://CDS.VizieR/J/A+A/638/L15
- Title:
- (16) Psyche. VLT/SPHERE images and shape models
- Short Name:
- J/A+A/638/L15
- Date:
- 23 Mar 2022
- Publisher:
- CDS
- Description:
- Asteroid (16) Psyche is the largest M-type asteroid in the main belt and the target of the NASA Psyche mission. It is also the only asteroid of this size (D>200km) known to be metal rich. Although various hypotheses have been proposed to explain the rather unique physical properties of this asteroid, a perfect understanding of its formation and bulk composition is still missing. We aim to refine the shape and bulk density of (16) Psyche and to perform a thorough analysis of its shape to better constrain possible formation scenarios and the structure of its interior. We obtained disk-resolved VLT/SPHERE/ZIMPOL images acquired within our ESO large program (ID 199.C-0074), which complement similar data obtained in 2018. Both data sets offer a complete coverage of Psyche's surface. These images were used to reconstruct the three-dimensional (3D) shape of Psyche with two independent shape modeling algorithms (MPCD and ADAM). A shape analysis was subsequently performed, including a comparison with equilibrium figures and the identification of mass deficit regions. Our 3D shape along with existing mass estimates imply a density of 4.20+/-0.60g/cm^3, which is so far the highest for a solar system object following the four telluric planets. Furthermore, the shape of Psyche presents small deviations from an ellipsoid, that is, prominently three large depressions along its equator. The flatness and density of Psyche are compatible with a formation at hydrostatic equilibrium as a Jacobi ellipsoid with a shorter rotation period of ~3h. Later impacts may have slowed down Psyche's rotation, which is currently ~4.2h, while also creating the imaged depressions. Our results open the possibility that Psyche acquired its primordial shape either after a giant impact while its interior was already frozen or while its interior was still molten owing to the decay of the short-lived radionuclide ^26^Al.
- ID:
- ivo://CDS.VizieR/J/A+A/478/321
- Title:
- QSO Type1/Type2 dichotomy
- Short Name:
- J/A+A/478/321
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- For Seyfert galaxies, the AGN unification model provides a simple and well-established explanation of the type 1/type 2 dichotomy through orientation-based effects. The generalization of this unification model to the higher luminosity AGNs that quasars are remains a key question. The recent detection of type 2 radio-quiet quasars seems to support such an extension. We propose a further test of this scenario. On the basis of a compilation of quasar host-galaxy position angles consisting of previously published data and of new measurements performed using HST Archive images, we investigate the possible existence of a correlation between the linear polarization position angle and the host-galaxy/extended emission position angle of quasars.
- ID:
- ivo://CDS.VizieR/J/MNRAS/416/2437
- Title:
- Quantified H I morphology of WHISP sample
- Short Name:
- J/MNRAS/416/2437
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The morphology of the atomic hydrogen (HI) disc of a spiral galaxy is the first component to be disturbed by a gravitational interaction such as a merger between two galaxies. We use a simple parametrization of the morphology of HI column density maps of the Westerbork observations of neutral Hydrogen in Irregular and SPiral galaxies (WHISP) project to select those galaxies that are likely undergoing a significant interaction. Merging galaxies occupy a particular part of parameter space defined by Asymmetry (A), the relative contribution of the 20 per cent brightest pixels to the second-order moment of the column density map (M20) and the distribution of the second-order moment over all the pixels (GM). Based on their HI morphology, we find that 13 per cent of the WHISP galaxies are in an interaction (Concentration-M20) and only 7 per cent are based on close companions in the data cube. This apparent discrepancy can be attributed to the difference in visibility time-scales: mergers are identifiable as close pairs for 0.5 Gyr but are identifiable for ~1Gyr by their disturbed HI morphology. Expressed as volume merger rates, the two estimates agree very well: 7 and 6.8x10^-3^mergers/Gyr/Mpc^3^ for paired and morphologically disturbed HI discs, respectively.
