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311. LIFE Target Database Cone Search
ID:
ivo://org.gavo.dc/life/q/cone
Title:
LIFE Target Database Cone Search
Short Name:
life_td cone
Date:
27 Dec 2024 08:31:05
Publisher:
The GAVO DC team
Description:
The LIFE Target Star Database contains information useful for the planned `LIFE mission`_ (mid-ir, nulling interferometer in space). It characterizes possible target systems including information about stellar, planetary and disk properties. The data itself is mainly a collection from different other catalogs. Note that LIFE's target database is living data. The content – and to some extent even structure – of these tables may change at any time without prior warning. .. _LIFE mission: https://life-space-mission.com/
312. 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.
313. 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.
314. LMC emission-line stars. Armagh survey
ID:
ivo://CDS.VizieR/J/A+A/555/A141
Title:
LMC emission-line stars. Armagh survey
Short Name:
J/A+A/555/A141
Date:
21 Oct 2021
Publisher:
CDS
Description:
Accurate astrometry is required to reliably cross-match 20th-century photographic catalogues against 21st-century digital surveys. The present work provides modern-area identifications and astrometry for the 801 emission-line objects "of stellar appearance" in the Armagh survey (the largest of its nature to date). Targets have been individually identified in digital images using the Armargh Atlas and, in most cases, unambiguously matched to entries in the UCAC astrometric catalogues.
315. Local structure & star formation history of the MW
ID:
ivo://CDS.VizieR/J/AJ/158/122
Title:
Local structure & star formation history of the MW
Short Name:
J/AJ/158/122
Date:
09 Mar 2022 22:00:00
Publisher:
CDS
Description:
Gaia DR2 (Cat. I/345) provides unprecedented precision in measurements of the distance and kinematics of stars in the solar neighborhood. Through applying unsupervised machine learning on DR2's 5D data set (3D position + 2D velocity), we identify a number of clusters, associations, and comoving groups within 1 kpc and |b|<30{deg} (many of which have not been previously known). We estimate their ages with the precision of ~0.15 dex. Many of these groups appear to be filamentary or string-like, oriented in parallel to the Galactic plane, and some span hundreds of parsec in length. Most of these string lack a central cluster, indicating that their filamentary structure is primordial, rather than the result of tidal stripping or dynamical processing. The youngest strings (<100 Myr) are orthogonal to the Local Arm. The older ones appear to be remnants of several other arm-like structures that cannot be presently traced by dust and gas. The velocity dispersion measured from the ensemble of groups and strings increase with age, suggesting a timescale for dynamical heating of ~300 Myr. This timescale is also consistent with the age at which the population of strings begins to decline, while the population in more compact groups continues to increase, suggesting that dynamical processes are disrupting the weakly bound string populations, leaving only individual clusters to be identified at the oldest ages. These data shed a new light on the local galactic structure and a large-scale cloud collapse.
316. Local velocity substructures in the Milky Way disk
ID:
ivo://CDS.VizieR/J/ApJ/847/123
Title:
Local velocity substructures in the Milky Way disk
Short Name:
J/ApJ/847/123
Date:
21 Oct 2021
Publisher:
CDS
Description:
We confirm, quantify, and provide a table of the coherent velocity substructure of the Milky Way disk within 2kpc of the Sun toward the Galactic anticenter, with a 0.2kpc resolution. We use the radial velocities of ~340000 F-type stars obtained with the Guoshoujing Telescope (also known as the Large Sky Area Multi-Object Fiber Spectroscopic Telescope, LAMOST), and proper motions derived from the PPMXL catalog. The PPMXL proper motions have been corrected to remove systematic errors by subtracting the average proper motions of galaxies and QSOs that have been confirmed in the LAMOST spectroscopic survey, and that are within 2.5{deg} of the star's position. We provide the resulting table of systematic offsets derived from the PPMXL proper motion measurements of extragalactic objects identified in the LAMOST spectroscopic survey. Using the corrected phase-space stellar sample, we find statistically significant deviations in the bulk disk velocity of 20km/s or more in the three-dimensional velocities of Galactic disk stars. The bulk velocity varies significantly over length scales of half a kiloparsec or less. The rotation velocity of the disk increases by 20km/s from the Sun's position to 1.5kpc outside the solar circle. Disk stars in the second quadrant, within 1kpc of the Sun, are moving radially toward the Galactic center and vertically toward a point a few tenths of a kiloparsec above the Galactic plane; looking down on the disk, the stars appear to move in a circular streaming motion with a radius of the order of 1kpc.
317. LOFAR long baselines at 140MHz Calibrators
ID:
ivo://CDS.VizieR/J/A+A/574/A73
Title:
LOFAR long baselines at 140MHz Calibrators
Short Name:
J/A+A/574/A73
Date:
21 Oct 2021
Publisher:
CDS
Description:
An efficient means of locating calibrator sources for international LOw Frequency ARray (LOFAR) is developed and used to determine the average density of usable calibrator sources on the sky for subarcsecond observations at 140MHz. We used the multi-beaming capability of LOFAR to conduct a fast and computationally inexpensive survey with the full international LOFAR array. Sources were preselected on the basis of 325MHz arcminute-scale flux density using existing catalogues. By observing 30 different sources in each of the 12 sets of pointings per hour, we were able to inspect 630 sources in two hours to determine if they possess a sufficiently bright compact component to be usable as LOFAR delay calibrators.
318. Lowell Proper Motion Survey 8991 Northern Stars
ID:
ivo://CDS.VizieR/I/79
Title:
Lowell Proper Motion Survey 8991 Northern Stars
Short Name:
I/79
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog contains a summary of many individual papers published in the Lowell Observatory Bulletins in the years 1958 to 1970. The data in the machine-readable version include observed positions, proper motions, estimated photographic magnitudes and colors, and references to identifications in other catalogs. Photoelectric data on the UBV system are included for many stars, but no attempt was made to find all existing photometry. The notes.dat file was computerized at the ADC by keying the notes directly to disk storage.
319. Lowell Proper Motion Survey - Southern Hemisphere
ID:
ivo://CDS.VizieR/I/112A
Title:
Lowell Proper Motion Survey - Southern Hemisphere
Short Name:
I/112A
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalog contains a summary of the Lowell Proper Motion Survey for the southern hemisphere. The catalog gives the position, motion, magnitude, and color of 2827 stars from the Lowell program.
320. low-ionization structures around NGC 1360
ID:
ivo://CDS.VizieR/J/MNRAS/473/2275
Title:
low-ionization structures around NGC 1360
Short Name:
J/MNRAS/473/2275
Date:
21 Oct 2021
Publisher:
CDS
Description:
Whether planetary nebulae (PNe) are predominantly the product of binary stellar evolution as some population synthesis models (PSM) suggest remains an open question. Around 50 short-period binary central stars (P~1d) are known, but with only four with measured orbital periods over 10 d, our knowledge is severely incomplete. Here we report on the first discovery from a systematic Southern African Large Telescope (SALT) High Resolution Spectrograph (HRS) survey for long-period binary central stars. We find a 142d orbital period from radial velocities of the central star of NGC 1360, HIP 16566. NGC 1360 appears to be the product of common-envelope (CE) evolution, with nebula features similar to post-CE PNe, albeit with an orbital period considerably longer than expected to be typical of post-CE PSM. The most striking feature is a newly identified ring of candidate low-ionization structures. Previous spatiokinematic modelling of the nebula gives a nebula inclination of 30{deg}+/-10{deg}, and assuming the binary nucleus is coplanar with the nebula, multiwavelength observations best fit a more massive, evolved white dwarf (WD) companion. A WD companion in a 142d orbit is not the focus of many PSM, making NGC 1360 a valuable system with which to improve future PSM work. HIP 16566 is amongst many central stars in which large radial velocity variability was found by low-resolution surveys. The discovery of its binary nature may indicate long-period binaries may be more common than PSM models predict.

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