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3261. J-PLUS. STAR-GALAXY-QSO Classification
ID:
ivo://CDS.VizieR/J/A+A/659/A144
Title:
J-PLUS. STAR-GALAXY-QSO Classification
Short Name:
J/A+A/659/A144
Date:
18 Mar 2022 08:13:24
Publisher:
CDS
Description:
In modern astronomy, machine learning has proved to be efficient and effective in mining big data from the newest telescopes. In this study, we construct a supervised machine-learning algorithm to classify the objects in the Javalambre Photometric Local Universe Survey first data release (J-PLUS DR1). The sample set is featured with 12-waveband photometry and labeled with spectrum-based catalogs, including Sloan Digital Sky Survey (SDSS) spectroscopic data, the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST), and VERON- CAT - the Veron Catalog of Quasars & AGN (VV13. Cat. VII/258). The performance of the classifier is presented with the applications of blind test validations based on RAdial Velocity Extension (RAVE), the Kepler Input Catalog (KIC), the 2 MASS (the Two Micron All Sky Survey) Redshift Survey (2MRS), and the UV-bright Quasar Survey (UVQS). A new algorithm was applied to constrain the potential extrapolation that could decrease the performance of the machine-learning classifier. The accuracies of the classifier are 96.5% in the blind test and 97.0% in training cross-validation. The F1-scores for each class are presented to show the balance between the precision and the recall of the classifier. We also discuss different methods to constrain the potential extrapolation.
3262. J-type carbon stars in LMC
ID:
ivo://CDS.VizieR/J/MNRAS/341/534
Title:
J-type carbon stars in LMC
Short Name:
J/MNRAS/341/534
Date:
21 Oct 2021
Publisher:
CDS
Description:
A sample of 1497 carbon stars in the Large Magellanic Cloud (LMC) has been observed in the red part of the spectrum with the 2dF facility on the Anglo-Australian Telescope. Of these, 156 have been identified as J-type (i.e. ^13^C-rich) carbon stars using a technique which provides a clear distinction between J stars and the normal N-type carbon stars that comprise the bulk of the sample, and yields few borderline cases. A simple two-dimensional classification of the spectra, based on their spectral slopes in different wavelength regions, has been constructed and found to be related to the more conventional c and j indices, modified to suit the spectral regions observed. Most of the J stars form a photometric sequence in the K-(J-K) colour-magnitude diagram, parallel to and 0.6mag fainter than the N-star sequence. A subset of the J stars (about 13 per cent) are brighter than this J-star sequence; most of these are spectroscopically different from the other J stars. The bright J stars have stronger CN bands than the other J stars and are found strongly concentrated in the central regions of the LMC. Most of the rather few stars in common with Hartwick and Cowley's sample (1988ApJ...334..135H) of suspected CH stars are J stars. Overall, the proportion of carbon stars identified as J stars is somewhat lower than has been found in the Galaxy. The Na D lines are weaker in the LMC J stars than in either the Galactic J stars or the LMC N stars, and do not seem to depend on temperature.
3263. Jupiter HST light curves
ID:
ivo://CDS.VizieR/J/ApJ/814/65
Title:
Jupiter HST light curves
Short Name:
J/ApJ/814/65
Date:
21 Oct 2021
Publisher:
CDS
Description:
Deducing the cloud cover and its temporal evolution from the observed planetary spectra and phase curves can give us major insight into the atmospheric dynamics. In this paper, we present Aeolus, a Markov chain Monte Carlo code that maps the structure of brown dwarf and other ultracool atmospheres. We validated Aeolus on a set of unique Jupiter Hubble Space Telescope (HST) light curves. Aeolus accurately retrieves the properties of the major features of the Jovian atmosphere, such as the Great Red Spot and a major 5{mu}m hot spot. Aeolus is the first mapping code validated on actual observations of a giant planet over a full rotational period. For this study, we applied Aeolus to J- and H-band HST light curves of 2MASS J21392676+0220226 and 2MASS J0136565+093347. Aeolus retrieves three spots at the top of the atmosphere (per observational wavelength) of these two brown dwarfs, with a surface coverage of 21%+/-3% and 20.3%+/-1.5%, respectively.
3264. K and evolutionary corrections
ID:
ivo://CDS.VizieR/J/A+AS/122/399
Title:
K and evolutionary corrections
Short Name:
J/A+AS/122/399
Date:
21 Oct 2021
Publisher:
CDS
Description:
K and evolutionary corrections are given for the E, Sa and Sc Hubble types for the following filters up to the redshift z=3: Johnson-Bessell & Brett photometric system: U, B, V, R, I, J, H, K filters Modified Thuan & Gunn system: gri filters Cousins system: Rc Ic filters Bj, Rf, In filters.
3265. K2-32 and K2-233 light and RV curves
ID:
ivo://CDS.VizieR/J/A+A/640/A48
Title:
K2-32 and K2-233 light and RV curves
Short Name:
J/A+A/640/A48
Date:
21 Oct 2021
Publisher:
CDS
Description:
High-precision planetary densities are key pieces of information necessary to derive robust atmospheric properties for extrasolar planets. Measuring precise masses is the most challenging part of this task, especially in multi-planetary systems. The ESO-K2 collaboration focuses on the follow-up of a selection of multi-planetary systems detected by the K2 mission using the HARPS instrument with this goal in mind. In this work, we measure the masses and densities of two multi-planetary systems: a four-planet near resonant chain system (K2-32) and a young (~400Myr old) planetary system consisting of three close-in small planets (K2-233). We obtained 199 new HARPS observations for K2-32 and 124 for K2-233 covering a long baseline of more than three years. We performed a joint analysis of the radial velocities and K2 photometry with PASTIS to precisely measure and constrained the properties of these planets, focusing on their masses and orbital properties. We find that K2-32 is a compact scaled-down version of the Solar System's architecture, with a small rocky inner planet (Me=2.1_-1.1_^+1.3^M_{earth}_, Pe~4.35-days) followed by an inflated Neptune-mass planet (Mb=15.0_-1.7_^+1.8^M_{earth}_, Pb~8.99-days) and two external sub-Neptunes (Mc=8.1+/-2.4M_{earth}_, Pc~20.66-days; Md=6.7+/-2.5M_{earth}_, Pd~31.72-days). K2-32 becomes one of the few multi-planetary systems with four or more planets known where all have measured masses and radii. Additionally, we constrain the masses of the three planets in the K2-233 system through marginal detection of their induced radial velocity variations. For the two inner Earth-size planets we constrain their masses at a 95% confidence level to be smaller than Mb<11.3M_{earth}_ (Pb~2.47-days), Mc<12.8M_{earth}_ (Pc~7.06-days). The outer planet is a sub-Neptune size planet with an inferred mass of Md=8.3_-4.7_^+5.2^M_{earth}_ (Md<21.1M_{earth}_, Pd~24.36-days). Our observations of these two planetary systems confirm for the first time the rocky nature of two planets orbiting a young star, with relatively short orbital periods (<7-days). They provide key information for planet formation and evolution models of telluric planets. Additionally, the Neptune-like derived masses of the three planets, K2-32 b, c, d, puts them in a relatively unexplored regime of incident flux and planet mass, which is key for transmission spectroscopy studies in the near future.
3266. K and M stars photometry
ID:
ivo://CDS.VizieR/J/AJ/105/1962
Title:
K and M stars photometry
Short Name:
J/AJ/105/1962
Date:
21 Oct 2021
Publisher:
CDS
Description:
Broadband UBVRI photometry is presented for 687 stars from among the dwarf K and M stars found spectroscopically by Vyssotsky [1958AJ.....63..211V]. Of these, 211 are without previous photometry.
3267. K2-111, an old system with two planets
ID:
ivo://CDS.VizieR/J/MNRAS/499/5004
Title:
K2-111, an old system with two planets
Short Name:
J/MNRAS/499/5004
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper reports on the detailed characterisation of the K2-111 planetary system with K2, WASP, and ASAS-SN photometry as well as high-resolution spectroscopic data from HARPS-N and ESPRESSO. The host, K2-111, is confirmed to be a mildly evolved (logg=4.17), iron-poor ([Fe/H]=-0.46), but alpha-enhanced ([{alpha}/Fe]=0.27), chromospherically quiet, very old thick disc G2 star. A global fit, performed by using PyORBIT shows that the transiting planet, K2-111 b, orbits with a period P_b_=5.3518+/-0.0004d, and has a planet radius of 1.82^+0.11^_-0.09_R_{Earth}_ and a mass of 5.29^+0.76^_-0.77_ M_{Earth}_, resulting in a bulk density slightly lower than that of the Earth. The stellar chemical composition and the planet properties are consistent with K2-111 b being a terrestrial planet with an iron core mass fraction lower than the Earth. We announce the existence of a second signal in the radial velocity data that we attribute to a non-transiting planet, K2-111 c, with an orbital period of 15.6785+/-0.0064 days, orbiting in near-3:1 mean-motion resonance with the transiting planet, and a minimum planet mass of 11.3+/-1.1 M_{Earth}_. Both planet signals are independently detected in the HARPS-N and ESPRESSO data when fitted separately. There are potentially more planets in this resonant system, but more well-sampled data are required to confirm their presence and physical parameters.
3268. Kappa Dra
ID:
ivo://CDS.VizieR/J/A+AS/107/403
Title:
Kappa Dra
Short Name:
J/A+AS/107/403
Date:
21 Oct 2021
Publisher:
CDS
Description:
(no description available)
3269. KASI-Yonsei Deep Imaging Survey of Clusters (KYDISC)
ID:
ivo://CDS.VizieR/J/ApJS/237/14
Title:
KASI-Yonsei Deep Imaging Survey of Clusters (KYDISC)
Short Name:
J/ApJS/237/14
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the KASI-Yonsei Deep Imaging Survey of Clusters targeting 14 clusters at 0.015<~z<~0.144 using the Inamori Magellan Areal Camera and Spectrograph on the 6.5m Magellan Baade telescope and the MegaCam on the 3.6m Canada-France-Hawaii Telescope. We provide a catalog of cluster galaxies that lists magnitudes, redshifts, morphologies, bulge-to-total ratios, and local density. Based on the 1409 spectroscopically confirmed cluster galaxies brighter than -19.8 in the r band, we study galaxy morphology, color, and visual features generated by galaxy mergers. We see a clear trend between morphological content and cluster velocity dispersion, which was not presented by previous studies using local clusters. Passive spirals are preferentially found in a highly dense region (i.e., cluster center), indicating that they have gone through environmental quenching. In deep images ({mu}_r'_~27mag/arcsec^2^), 20% of our sample shows signatures of recent mergers, which is not expected from theoretical predictions and a low frequency of ongoing mergers in our sample (~4%). Such a high fraction of recent mergers in the cluster environment supports a scenario that the merger events that made the features have preceded the galaxy accretion into the cluster environment. We conclude that mergers affect a cluster population mainly through the preprocessing of recently accreted galaxies.
3270. Kazarian galaxies catalog
ID:
ivo://CDS.VizieR/VII/254
Title:
Kazarian galaxies catalog
Short Name:
VII/254
Date:
21 Oct 2021
Publisher:
CDS
Description:
The entire KG (KG) catalog is presented which combines extensive new measurements of their optical parameters with a literature and database search. The measurements were made using images extracted from the STScI Digitized Sky Survey (DSS) of Jpg(blue), Fpg(red) and Ipg(NIR) band photographic sky survey plates obtained by the Palomar and UK Schmidt telescopes. We provide accurate coordinates, morphological type, spectral and activity classes, blue apparent diameters, axial ratios, position angles, red, blue and NIR apparent magnitudes, as well as counts of neighboring objects in a circle of radius 50kpc from centers of KG. Special attention was paid to the individual descriptions of the galaxies in the original Kazarian lists, which clarified many cases of misidentifications of the objects, particularly among interacting systems. The total number of individual Kazarian objects in the database is now 706. We also include the redshifts which are now available for 404 galaxies, and the 2MASS infrared magnitudes for 598 KG. The database also includes extensive notes, which summarize information about the membership of KG in different systems of galaxies, and about revised activity classes and redshifts. An atlas of several interesting subclasses of KG is also presented.