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1401. Light-Motion Curve Catalogue (LMCC) in Stripe 82
ID:
ivo://CDS.VizieR/V/141
Title:
Light-Motion Curve Catalogue (LMCC) in Stripe 82
Short Name:
V/141
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a public archive of light-motion curves in Sloan Digital Sky Survey (SDSS) Stripe 82, covering 99{deg} in right ascension (20.7h to 3.3h) and spanning 2.52{deg} in declination (-1.26 to 1.26), for a total sky area of about 249sq.deg. Stripe 82 has been repeatedly monitored in the u, g, r, i and z bands over a seven-year baseline. Objects are cross-matched between runs, taking into account the effects of any proper motion. The resulting catalogue contains almost 4million light-motion curves of stellar objects and galaxies. The photometry are recalibrated to correct for varying photometric zeropoints, achieving ~20mmag and 30mmag root-mean-square (RMS) accuracy down to 18mag in the g, r, i and z bands for point sources and extended sources, respectively. The astrometry are recalibrated to correct for inherent systematic errors in the SDSS astrometric solutions, achieving 32mas and 35mas RMS accuracy down to 18mag for point sources and extended sources, respectively. For each light-motion curve, 229 photometric and astrometric quantities are derived and stored in a higher-level catalogue. On the photometric side, these include mean exponential and PSF magnitudes along with uncertainties, RMS scatter, {chi}^2^ per degree of freedom, various magnitude distribution percentiles, object type (stellar or galaxy), and eclipse, Stetson and Vidrih variability indices. On the astrometric side, these quantities include mean positions, proper motions as well as their uncertainties and {chi}^2^ per degree of freedom. The here presented light-motion curve catalogue is complete down to r~21.5mag and is at present the deepest large-area photometric and astrometric variability catalogue available.
1402. LINEAR. III. Catalog of periodic variables
ID:
ivo://CDS.VizieR/J/AJ/146/101
Title:
LINEAR. III. Catalog of periodic variables
Short Name:
J/AJ/146/101
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe the construction of a highly reliable sample of ~7000 optically faint periodic variable stars with light curves obtained by the asteroid survey LINEAR across 10000deg^2^ of the northern sky. The majority of these variables have not been cataloged yet. The sample flux limit is several magnitudes fainter than most other wide-angle surveys; the photometric errors range from ~0.03mag at r=15 to ~0.20mag at r=18. Light curves include on average 250 data points, collected over about a decade. Using Sloan Digital Sky Survey (SDSS) based photometric recalibration of the LINEAR data for about 25 million objects, we selected ~200000 most probable candidate variables with r<17 and visually confirmed and classified ~7000 periodic variables using phased light curves. The reliability and uniformity of visual classification across eight human classifiers was calibrated and tested using a catalog of variable stars from the SDSS Stripe 82 region and verified using an unsupervised machine learning approach. The resulting sample of periodic LINEAR variables is dominated by 3900 RR Lyrae stars and 2700 eclipsing binary stars of all subtypes and includes small fractions of relatively rare populations such as asymptotic giant branch stars and SX Phoenicis stars. We discuss the distribution of these mostly uncataloged variables in various diagrams constructed with optical-to-infrared SDSS, Two Micron All Sky Survey, and Wide-field Infrared Survey Explorer photometry, and with LINEAR light-curve features. We find that the combination of light-curve features and colors enables classification schemes much more powerful than when colors or light curves are each used separately. An interesting side result is a robust and precise quantitative description of a strong correlation between the light-curve period and color/spectral type for close and contact eclipsing binary stars ({beta} Lyrae and W UMa): as the color-based spectral type varies from K4 to F5, the median period increases from 5.9hr to 8.8hr. These large samples of robustly classified variable stars will enable detailed statistical studies of the Galactic structure and physics of binary and other stars and we make these samples publicly available.
1403. Linear structural param. of SDSS+UKIDSS+WISE gal.
ID:
ivo://CDS.VizieR/J/ApJS/244/3
Title:
Linear structural param. of SDSS+UKIDSS+WISE gal.
Short Name:
J/ApJS/244/3
Date:
21 Oct 2021
Publisher:
CDS
Description:
Accurate measurements of galaxy structure are prerequisites for quantitative investigation of galaxy properties or evolution. Yet galaxy inclination, through projection and varying dust effects, strongly affects many commonly used metrics of galaxy structure. Here we demonstrate that collapsing a galaxy's light distribution onto its major axis gives a "linear brightness profile" that is unaffected by projection. In analogy to widely used half-light radius and concentrations, we use two metrics to describe this light distribution: x_50_, the linear distance containing half of the galaxy's luminosity, and c_x_=x_90_/x_50_, the ratio between the 90% light distance and the 50% light distance. In order to minimize the effects of dust, we apply this technique to a diverse sample of galaxies with moderately deep and high-resolution K-band imaging from the UKIDSS Large Area Survey. Using simulated galaxy images, we find that while our measurements are primarily limited by the surface brightness in the outer parts of galaxies, most local galaxies have high enough surface brightnesses to result in reliable measurements. When applied to real data, our metrics vary from face-on to edge-on by typically ~5% in c_x_ and ~12% in x_50_, representing factors of several to 10 improvement over existing optical and some infrared catalog measures of galaxy structure. We release a sample of 23804 galaxies with inclination-independent and dust-penetrated observational proxies for stellar mass, specific star formation rate, half-light size, and concentration.
1404. Lists of arm and interarm supernovae
ID:
ivo://CDS.VizieR/J/MNRAS/459/3130
Title:
Lists of arm and interarm supernovae
Short Name:
J/MNRAS/459/3130
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using a sample of 215 supernovae (SNe), we analyse their positions relative to the spiral arms of their host galaxies, distinguishing grand-design (GD) spirals from non-GD (NGD) galaxies. We find that: (1) in GD galaxies, an offset exists between the positions of Ia and core-collapse (CC) SNe relative to the peaks of arms, while in NGD galaxies the positions show no such shifts; (2) in GD galaxies, the positions of CC SNe relative to the peaks of arms are correlated with the radial distance from the galaxy nucleus. Inside (outside) the corotation radius, CC SNe are found closer to the inner (outer) edge. No such correlation is observed for SNe in NGD galaxies nor for SNe Ia in either galaxy class; (3) in GD galaxies, SNe Ibc occur closer to the leading edges of the arms than do SNe II, while in NGD galaxies they are more concentrated towards the peaks of arms. In both samples of hosts, the distributions of SNe Ia relative to the arms have broader wings. These observations suggest that shocks in spiral arms of GD galaxies trigger star formation in the leading edges of arms affecting the distributions of CC SNe (known to have short-lived progenitors). The closer locations of SNe Ibc versus SNe II relative to the leading edges of the arms supports the belief that SNe Ibc have more massive progenitors. SNe Ia having less massive and older progenitors, have more time to drift away from the leading edge of the spiral arms.
1405. Lithium abundances of KOIs from CKS spectra
ID:
ivo://CDS.VizieR/J/ApJ/855/115
Title:
Lithium abundances of KOIs from CKS spectra
Short Name:
J/ApJ/855/115
Date:
21 Oct 2021
Publisher:
CDS
Description:
The lithium doublet at 6708{AA} provides an age diagnostic for main sequence FGK dwarfs. We measured the abundance of lithium in 1305 stars with detected transiting planets from the Kepler mission using high-resolution spectroscopy. Our catalog of lithium measurements from this sample has a range of abundance from A(Li)=3.11+/-0.07 to an upper limit of -0.84dex. For a magnitude-limited sample that comprises 960 of the 1305 stars, our Keck-HIRES spectra have a median signal-to-noise ratio of 45 per pixel at ~6700{AA} with spectral resolution {lambda}/{Delta}{lambda}=R=55000. We identify 80 young stars that have A(Li) values greater than the Hyades at their respective effective temperatures; these stars are younger than ~650Myr, the approximate age of the Hyades. We then compare the distribution of A(Li) with planet size, multiplicity, orbital period, and insolation flux. We find larger planets preferentially in younger systems, with an A-D two-sided test p-value=0.002, a>3{sigma} confidence that the older and younger planet samples do not come from the same parent distribution. This is consistent with planet inflation/photoevaporation at early ages. The other planet parameters (Kepler planet multiplicity, orbital period, and insolation flux) are uncorrelated with age.
1406. LITTLE THINGS dwarf irregular galaxies FUV regions
ID:
ivo://CDS.VizieR/J/AJ/151/136
Title:
LITTLE THINGS dwarf irregular galaxies FUV regions
Short Name:
J/AJ/151/136
Date:
21 Oct 2021
Publisher:
CDS
Description:
We examine FUV images of the LITTLE THINGS sample of nearby dwarf irregular (dIrr) and Blue Compact Dwarf galaxies to identify distinct young regions in their far outer disks. We use these data, obtained with the Galaxy Evolution Explorer satellite, to determine the furthest radius at which in situ star formation can currently be identified. The FUV knots are found at distances from the center of the galaxies of 1-8 disk scale lengths and have ages of =<20 Myr and masses of 20 M_{sun}_ to 1x10^5^ M_{sun}_. The presence of young clusters and OB associations in the outer disks of dwarf galaxies shows that dIrrs do have star formation taking place there in spite of the extreme nature of the environment. Most regions are found where the H I surface density is ~1 M_{sun}_/pc^2^, though both the H I and dispersed old stars go out much further. This limiting density suggests a cutoff in the ability to form distinct OB associations and perhaps even stars. We compare the star formation rates in the FUV regions to the average rates expected at their radii and beyond from the observed gas, using the conventional correlation for gas-rich regions. The localized rates are typically 10% of the expected average rates for the outer disks. Either star formation in dIrrs at surface densities <1 M_{sun}_/pc^2^ occurs without forming distinct associations, or the Kennicutt-Schmidt relation over-predicts the rate beyond this point. In the latter case, the stellar disks in the far-outer parts of dIrrs result from scattering of stars from the inner disk.
1407. Liverpool-Edinburgh High Proper Motion Catalogue
ID:
ivo://CDS.VizieR/J/A+A/421/763
Title:
Liverpool-Edinburgh High Proper Motion Catalogue
Short Name:
J/A+A/421/763
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a machine selected catalogue of 11289 objects with proper motions exceeding 0.18arcsec/yr and an R-band faint magnitude limit of 19.5mag. The catalogue was produced using SuperCOSMOS digitized R-Band ESO and UK Schmidt Plates in 287 Schmidt fields covering almost 7000 square degrees (~17% of the whole sky) at the South Galactic Cap. The catalogue includes UK Schmidt BJ and I magnitudes for all of the stars as well as 2MASS magnitudes for 10447 of the catalogue stars. We also show that the NLTT is ~95% complete for DE>-32.5{deg}.
1408. Liverpool-Edinburgh high proper motion survey
ID:
ivo://CDS.VizieR/J/A+A/397/575
Title:
Liverpool-Edinburgh high proper motion survey
Short Name:
J/A+A/397/575
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a catalogue of 6206 stars which have proper motions exceeding 0.18 arcsec/yr with an R-band faint magnitude limit of 19.5mag. This catalogue has been produced using SuperCOSMOS digitized R-Band ESO and UK Schmidt Plates in 131 Schmidt fields covering more than 3,000 square degrees (>7.5% of the whole sky) at the South Galactic Cap. The survey is >90% complete within the nominal limits of the Luyten Two Tenths Catalogue of m_R_<18.5mag and 0.2<{mu}<2.5arcsec/yr, and is >80% complete for m_R_<19.5mag and {mu}<2.5arcsec/yr.
1409. LkH{alpha} 101 and the young cluster in NGC 1579
ID:
ivo://CDS.VizieR/J/AJ/128/1233
Title:
LkH{alpha} 101 and the young cluster in NGC 1579
Short Name:
J/AJ/128/1233
Date:
21 Oct 2021
Publisher:
CDS
Description:
The central region of the dark cloud L1482 is illuminated by LkH{alpha} 101, a heavily reddened (A_V_~10mag) high-luminosity (>=8x10^3^L_Sun_) star having an unusual emission-line spectrum plus a featureless continuum. About 35 much fainter (mostly between R=16 and >21) H{alpha} emitters have been found in the cloud. Their color-magnitude distribution suggests a median age of about 0.5Myr, with considerable dispersion. There are also at least five bright B-type stars in the cloud, presumably of about the same age; none show the peculiarities expected of HAeBe stars. Dereddened, their apparent V magnitudes lead to a distance of about 700pc. Radio observations suggest that the optical object LkH{alpha} 101 is in fact a hot star surrounded by a small H II region, both inside an optically thick dust shell.
1410. LMC bar star clusters
ID:
ivo://CDS.VizieR/J/A+A/606/A21
Title:
LMC bar star clusters
Short Name:
J/A+A/606/A21
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report results on star clusters located in the South-Eastern half of the Large Magellanic (LMC) bar fromWashington CT1 photometry. Using appropriate kernel density estimators we detected 73 star cluster candidates, three of which do not show any detectable trace of star cluster sequences in their colour-magnitude diagrams (CMDs).We did not detect other 38 previously catalogued clusters, which could not be recognized when visually inspecting the C and T1 images either; the distribution of stars in their respective fields do not resemble that of an stellar aggregate. They represent ~33 per cent of all catalogued objects located within the analysed LMC bar field. From matching theoretical isochrones to the cluster CMDs cleaned from field star contamination, we derived ages in the range 7.2<log(t[yr^-1^])<10.1. As far as we are aware, this is the first time homogeneous age estimates based on resolved stellar photometry are obtained for most of the studied clusters. We built the cluster frequency (CF) for the surveyed area, and found that the major star cluster formation activity has taken place during the period log(t[yr^-1^])~8.0-9.0. Since ~100Myr ago, clusters have been formed during few bursting formation episodes. When comparing the observed CF to that recovered from the star formation rate we found noticeable differences, which suggests that field star and star cluster formation histories could have been significantly different.