- ID:
- ivo://CDS.VizieR/J/AJ/159/264
- Title:
- Observation of 10 Vesta asteroids with WISE/NEOWISE
- Short Name:
- J/AJ/159/264
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work, we investigate the size, thermal inertia, surface roughness, and geometric albedo of 10 Vesta family asteroids using the Advanced Thermophysical Model (ATM), based on the thermal-infrared data acquired by mainly NASA's Wide-field Infrared Survey Explorer (WISE). Here, we show that the average thermal inertia and geometric albedo of the investigated Vesta family members are 42J/m^2^/s^1/2^/K and 0.314, respectively, where the derived effective diameters are less than 10km. Moreover, the family members have a relatively low roughness fraction on their surfaces. The similarity in thermal inertia and geometric albedo among the V-type Vesta family members may reveal their close connection in origin and evolution. As the fragments of the cratering event of Vesta, the family members may have undergone a similar evolutionary process, thereby leading to very close thermal properties. Finally, we estimate their regolith grain sizes with different volume filling factors.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/159/255
- Title:
- Observation & radial velocity of WASP-150 & WASP-176
- Short Name:
- J/AJ/159/255
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of two transiting exoplanets from the Wide Angle Search for Planets (WASP) survey, WASP-150b and WASP-176b. WASP-150b is an eccentric (e=0.38) hot Jupiter on a 5.6day orbit around a V=12.03, F8 main-sequence host. The host star has a mass and radius of 1.4M_{sun}_ and 1.7R_{sun}_ respectively. WASP-150b has a mass and radius of 8.5M_J_ and 1.1R_J_, leading to a large planetary bulk density of 6.4{rho}_J_. WASP-150b is found to be ~3Gyr old, well below its circularization timescale, supporting the eccentric nature of the planet. WASP-176b is a hot Jupiter planet on a 3.9day orbit around a V=12.01, F9 sub-giant host. The host star has a mass and radius of 1.3M{sun} and 1.9R{sun}. WASP-176b has a mass and radius of 0.86M_J_ and 1.5R_J_, respectively, leading to a planetary bulk density of 0.23{rho}_J_.
- ID:
- ivo://CDS.VizieR/J/ApJ/669/446
- Title:
- Observations of SiO masers
- Short Name:
- J/ApJ/669/446
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of SiO millimeter line observations of a sample of known SiO maser sources covering a wide dust temperature range. A cold part of the sample was selected from the SiO maser sources found in our recent SiO maser survey of cold dusty objects. The aim of the present research is to investigate the causes of the correlation between infrared colors and SiO maser intensity ratios among different transition lines. In particular, the correlation between infrared colors and SiO maser intensity ratio among the J=1-0 v=1, 2, and 3 lines are our main concern in this paper. We observed in total 75 SiO maser sources with the Nobeyama 45m telescope quasi-simultaneously in the SiO J=1-0 v=0, 1, 2, 3, 4 and J=2-1 v=1, 2 lines. We also observed the sample in the ^29^SiO J=1-0 v=0 and J=2-1 v=0 lines, ^30^SiO J=1-0 v=0 line, and the H_2_O 61,6-52,3 line.
- ID:
- ivo://CDS.VizieR/J/PAZh/30/37
- Title:
- Observations of supernovae in 1997-1999
- Short Name:
- J/PAZh/30/37
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Photometric observations of 15 supernovae discovered in the period 1997-1999 are presented.
- ID:
- ivo://CDS.VizieR/J/AJ/159/267
- Title:
- Observations & radial velocity of HATS-71b
- Short Name:
- J/AJ/159/267
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of HATS-71b, a transiting gas giant planet on a P=3.7955day orbit around a G=15.35mag M3 dwarf star. HATS-71 is the coolest M dwarf star known to host a hot Jupiter. The loss of light during transits is 4.7%, more than in any other confirmed transiting planet system. The planet was identified as a candidate by the ground-based HATSouth transit survey. It was confirmed using ground-based photometry, spectroscopy, and imaging, as well as space-based photometry from the NASA Transiting Exoplanet Survey Satellite mission (TIC234523599). Combining all of these data, and utilizing Gaia DR2, we find that the planet has a radius of 1.024{+/-}0.018R_J_ and mass of 0.37{+/-}0.24M_J_ (95% confidence upper limit of <0.80M_J_), while the star has a mass of 0.4861{+/-}0.0060M_{sun}_ and a radius of 0.4783{+/-}0.0060R_{sun}_.
- ID:
- ivo://CDS.VizieR/J/ApJ/788/72
- Title:
- Observed sample of z~0.7 massive galaxies
- Short Name:
- J/ApJ/788/72
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Detailed studies of the stellar populations of intermediate-redshift galaxies can shed light onto the processes responsible for the growth of the massive galaxy population in the last 8 billion years. We here take a step toward this goal by means of deep, multiobject rest-frame optical spectroscopy, performed with the Inamori Magellan Areal Camera and Spectrograph on the Magellan telescope, of a sample of ~70 galaxies in the Extended Chandra Deep Field South survey with redshift 0.65<=z<=0.75, apparent R>22.7 mag_Vega_, and stellar mass >10^10^ M_{sun}_. We measure velocity dispersion and stellar absorption features for individual sources. We interpret them by means of a large Monte Carlo library of star formation histories, following the Bayesian approach adopted for previous low redshift studies, and derive constraints on the stellar mass, mean stellar age, and stellar metallicity of these galaxies. We characterize for the first time the relations between stellar age and stellar mass and between stellar metallicity and stellar mass at z~0.7 for the galaxy population as a whole and for quiescent and star-forming galaxies separately. These relations of increasing age and metallicity with galaxy mass for the galaxy population as a whole have a similar shape as the z~0.1 analog derived for Sloan Digital Sky Survey galaxies but are shifted by -0.28 dex in age and by -0.13 dex in metallicity, at odds with simple passive evolution. Considering z=0.7 quiescent galaxies alone, we find that no additional star formation and chemical enrichment are required for them to evolve into the present-day quiescent population. However, other observations require the quiescent population to grow from z=0.7 to the present day. This growth could be supplied by the quenching of a fraction of z=0.7 M_{sstarf}_>10^11^ M_{sun}_ star-forming galaxies with metallicities already comparable to those of quiescent galaxies, thus leading to the observed increase of the scatter in age without affecting the metallicity distribution. However, rapid quenching of the entire population of massive star-forming galaxies at z=0.7 would be inconsistent with the age- and metallicity-mass relations for the population as a whole and with the metallicity distribution of star-forming galaxies only, which are, on average, 0.12 dex less metal rich than their local counterparts. This indicates chemical enrichment until the present in at least a fraction of the z=0.7 star-forming galaxies in our sample.
- ID:
- ivo://CDS.VizieR/J/AcA/43/209
- Title:
- OB stars extinction based in IR photometry
- Short Name:
- J/AcA/43/209
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The paper presents an extensive survey of interstellar extinction curves derived from the near IR photometric measurements of early type stars belonging to our Galaxy. This survey is more extensive and deeper than any other one, based on spectral data. The IR magnitudes of about 500 O and B type stars with E(B-V)>=0.05 were selected from literature. The IR color excesses are determined with the aid of "artificial standards". The results indicate that the extinction law changes from place to place. The mean galactic extinction curve in the near IR is very similar in different directions and changes very little from the value R=3.10+/-0.05 obtained in this paper.
- ID:
- ivo://CDS.VizieR/J/A+A/538/A142
- Title:
- OB stars in NGC 6334 and NGC 6357
- Short Name:
- J/A+A/538/A142
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Star-forming complexes are large structures exhibiting massive star-formation at different stages of evolution, from dense cores to well-developed HII regions. They are very interesting for the study of the formation and evolution of stars. NGC 6334 and NGC 6357 are two active and relatively nearby star-forming complexes. From the extinction map and the sub-mm cold dust emission, and because they have similar velocities, these regions are most likely connected. However, located in the direction of the Galactic center their radial velocity is not representative of their distance. An alternative is then to determine the distance of NGC 6334 and NGC 6357 from their stellar content. Our aim is to perform a census of O-B3 ionising stars in NGC 6334 and NGC 6357, to determine the extinction coefficient, and the distance of both regions. A census of O-B3 stars is an essential basis for estimating the statistical lifetime of the earliest massive star-forming phases.
- ID:
- ivo://CDS.VizieR/J/AN/331/349
- Title:
- O, B-type & red supergiant masses and luminosities
- Short Name:
- J/AN/331/349
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Massive stars are of interest as progenitors of supernovae, i.e. neutron stars and black holes, which can be sources of gravitational waves. Recent population synthesis models can predict neutron star and gravitational wave observations but deal with a fixed supernova rate or an assumed initial mass function for the population of massive stars. Here we investigate those massive stars, which are supernova progenitors, i.e. with O- and early B-type stars, and also all supergiants within 3kpc. We restrict our sample to those massive stars detected both in 2MASS and observed by Hipparcos, i.e. only those stars with parallax and precise photometry. To determine the luminosities we calculated the extinctions from published multi-colour photometry, spectral types, luminosity class, all corrected for multiplicity and recently revised Hipparcos distances. We use luminosities and temperatures to estimate the masses and ages of these stars using different models from different authors.
2110. OCSVM anomalies
- ID:
- ivo://CDS.VizieR/J/A+A/606/A39
- Title:
- OCSVM anomalies
- Short Name:
- J/A+A/606/A39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Wide-angle photometric surveys of previously uncharted sky areas or wavelength regimes will always bring in unexpected sources - novelties or even anomalies - whose existence and properties cannot be easily predicted from earlier observations. Such objects can be efficiently located with novelty detection algorithms. Here we present an application of such a method, called one-class support vector machines (OCSVM), to search for anomalous patterns among sources preselected from the mid-infrared AllWISE catalogue covering the whole sky. To create a model of expected data we train the algorithm on a set of objects with spectroscopic identifications from the SDSS DR13 database, present also in AllWISE. The OCSVM method detects as anomalous those sources whose patterns - WISE photometric measurements in this case - are inconsistent with the model. Among the detected anomalies we find artefacts, such as objects with spurious photometry due to blending, but more importantly also real sources of genuine astrophysical interest. Among the latter, OCSVM has identified a sample of heavily reddened AGN/quasar candidates distributed uniformly over the sky and in a large part absent from other WISE-based AGN catalogues. It also allowed us to find a specific group of sources of mixed types, mostly stars and compact galaxies. By combining the semi-supervised OCSVM algorithm with standard classification methods it will be possible to improve the latter by accounting for sources which are not present in the training sample, but are otherwise well-represented in the target set. Anomaly detection adds flexibility to automated source separation procedures and helps verify the reliability and representativeness of the training samples. It should be thus considered as an essential step in supervised classification schemes to ensure completeness and purity of produced catalogues.
