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3401. Coupling factors of 5166 KIC
ID:
ivo://CDS.VizieR/J/A+A/600/A1
Title:
Coupling factors of 5166 KIC
Short Name:
J/A+A/600/A1
Date:
21 Oct 2021
Publisher:
CDS
Description:
The power of asteroseismology relies on the capability of global oscillations to infer the stellar structure. For evolved stars, we benefit from unique information directly carried out by mixed modes that probe their radiative cores. This third article of the series devoted to mixed modes in red giants focuses on their coupling factors, which have remained largely unexploited up to now. With the measurement of coupling factors, we intend to give physical constraints on the regions surrounding the radiative core and the hydrogen-burning shell of subgiants and red giants. A new method for measuring the coupling factor of mixed modes was implemented, which was derived from the method recently implemented for measuring period spacings. This new method was automated so that it could be applied to a large sample of stars. Coupling factors of mixed modes were measured for thousands of red giants. They show specific variation with mass and evolutionary stage. Weak coupling is observed for the most evolved stars on the red giant branch only; large coupling factors are measured at the transition between subgiants and red giants as well as in the red clump. The measurement of coupling factors in dipole mixed modes provides a new insight into the inner interior structure of evolved stars. While the large frequency separation and the asymptotic period spacings probe the envelope and core, respectively, the coupling factor is directly sensitive to the intermediate region in between and helps determine its extent. Observationally, the determination of the coupling factor is a prior to precise fits of the mixed-mode pattern and can now be used to address further properties of the mixed-mode pattern, such as the signature of buoyancy glitches and core rotation.
3402. COUP: observations and source lists
ID:
ivo://CDS.VizieR/J/ApJS/160/319
Title:
COUP: observations and source lists
Short Name:
J/ApJS/160/319
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a description of the data reduction methods and the derived catalog of more than 1600 X-ray point sources from the exceptionally deep 2003 January Chandra X-Ray Observatory (Chandra) observation of the Orion Nebula Cluster and embedded populations around OMC-1. The observation was obtained with Chandra's Advanced CCD Imaging Spectrometer (ACIS) and has been nicknamed the Chandra Orion Ultradeep Project (COUP). With an 838ks exposure made over a continuous period of 13.2 days, the COUP observation provides the most uniform and comprehensive data set on the X-ray emission of normal stars ever obtained in the history of X-ray astronomy.
3403. Cousins RI photometry in IC 348
ID:
ivo://CDS.VizieR/J/AJ/127/1602
Title:
Cousins RI photometry in IC 348
Short Name:
J/AJ/127/1602
Date:
21 Oct 2021
Publisher:
CDS
Description:
The extremely young cluster IC 348 has been monitored photometrically over five observing seasons from 1998 December 10 to 2003 March 26 in Cousins I with a 0.6m telescope at Van Vleck Observatory. Twenty-eight periodic variables and 16 irregular variables have been identified. The variability study is most sensitive for stars with I<14.3mag; at that brightness level, we find that 24 of the 27 known pre-main-sequence (PMS) cluster members in the monitored field are variables, illustrating the value of photometric monitoring for identifying PMS cluster members. Among this brighter sample, 14 of the 16 known K or M-type weak-line T Tauri stars (WTTS) were found to be periodic variables, while all five of the known classical T Tauri stars (CTTS) were found to be irregular variables. In the full sample, which includes 150 stars with I as faint as 18, we find that 40% of the 63 WTTS are detected as variables, nearly all of them periodic, while 55% of the 20 CTTS are also detected as variable, with none of them periodic.
3404. Cousins RI photometry of NGC 2169
ID:
ivo://CDS.VizieR/J/MNRAS/376/580
Title:
Cousins RI photometry of NGC 2169
Short Name:
J/MNRAS/376/580
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have used Cousins RI CCD photometry from the Isaac Newton telescope and intermediate-resolution spectroscopy from the Gemini North telescope to identify and characterize low-mass (0.15<M/M_{sun}_<1.3) pre-main-sequence stars in the young open cluster NGC 2169. Isochrone fitting to the high- and low-mass populations yields an intrinsic distance modulus of 10.13^+0.06^_-0.09_mag and a model-dependent age of 9+/-2Myr. Compared to the nearby, kinematically defined groups of a similar age, NGC 2169 has a large low-mass population which potentially offers a more precise statistical investigation of several aspects of star formation and early stellar evolution. By modelling the distribution of low-mass stars in the IC versus RC IC diagram, we find that any age spread among cluster members has a Gaussian full width at half-maximum (FWHM) 2.5Myr. A young age and a small age spread (<10Myr) are supported by the lack of significant lithium depletion in the vast majority of cluster members. There is no clear evidence for accretion or warm circumstellar dust in the low-mass members of NGC 2169, bolstering the idea that strong accretion has ceased and inner discs have dispersed in almost all low-mass stars by ages of 10Myr.
3405. CO velocities in southern HII regions
ID:
ivo://CDS.VizieR/J/A+A/417/107
Title:
CO velocities in southern HII regions
Short Name:
J/A+A/417/107
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present ^12^CO(1-0), ^12^CO(2-1) and/or ^13^CO(1-0) observations in the direction of HII regions located in the southern Galactic plane. The CO lines have been fitted with gaussian lines. For each direction (indicated by the galactic coordinates put in the source identification) we detect several components. The parameter, central position, line width and intensity of every component are listed in tables 2 and 3. In addition, we indicate, in the last two columns the velocity from radio and H{alpha} data of the pointed HII region.
3406. Covering factor of warm dust in quasars
ID:
ivo://CDS.VizieR/J/MNRAS/430/3445
Title:
Covering factor of warm dust in quasars
Short Name:
J/MNRAS/430/3445
Date:
21 Oct 2021
Publisher:
CDS
Description:
By combining newly obtained infrared photometric data from the All-Sky Data Release of the Wide-field Infrared Survey Explorer with spectroscopic data from the Seventh Data Release of the Sloan Digital Sky Survey, we study the covering factor of warm dust (CFWD) for a large quasar sample, as well as the relations between CFWD and other physical parameters of quasars. We find a strong correlation between the flux ratio in the mid-infrared to near-ultraviolet and the slope of the near-ultraviolet spectra, which is interpreted as a dust extinction effect. After correcting for dust extinction utilizing the above correlation, we examine the relations between CFWD and active galactic nucleus properties: bolometric luminosity (L_bol_), black hole mass (M_BH_) and Eddington ratio (L/L_Edd_). We confirm the anticorrelation between CFWD and L_bol_. Further, we find that CFWD is anticorrelated with M_BH_ but is independent of L/L_Edd_. Radio-loud quasars are found to follow the same correlations as radio-quiet quasars. Monte Carlo simulations show that the anisotropy of the UV-optical continuum of the accretion disc can have a significant effect, but is not likely to dominate the CFWD-L_bol_ correlation.
3407. C/O vs Mg/Si of planetary systems
ID:
ivo://CDS.VizieR/J/ApJ/725/2349
Title:
C/O vs Mg/Si of planetary systems
Short Name:
J/ApJ/725/2349
Date:
21 Oct 2021
Publisher:
CDS
Description:
Theoretical studies suggest that C/O and Mg/Si are the most important elemental ratios in determining the mineralogy of terrestrial planets. The C/O ratio controls the distribution of Si among carbide and oxide species, while Mg/Si gives information about the silicate mineralogy. We present a detailed and uniform study of C, O, Mg, and Si abundances for 61 stars with detected planets and 270 stars without detected planets from the homogeneous high-quality unbiased HARPS GTO sample, together with 39 more planet-host stars from other surveys. We determine these important mineralogical ratios and investigate the nature of the possible terrestrial planets that could have formed in those planetary systems. We find mineralogical ratios quite different from those of the Sun, showing that there is a wide variety of planetary systems which are not similar to our solar system. Many planetary host stars present an Mg/Si value lower than 1, so their planets will have a high Si content to form species such as MgSiO_3_. This type of composition can have important implications for planetary processes such as plate tectonics, atmospheric composition, or volcanism.
3408. C/O vs Mg/Si ratios in solar type stars
ID:
ivo://CDS.VizieR/J/A+A/614/A84
Title:
C/O vs Mg/Si ratios in solar type stars
Short Name:
J/A+A/614/A84
Date:
21 Oct 2021
Publisher:
CDS
Description:
We aim to present a detailed study of the magnesium-to-silicon and carbon-to-oxygen ratios (Mg/Si and C/O) and their importance in determining the mineralogy of planetary companions. Using 499 solar-like stars from the HARPS sample, we determined C/O and Mg/Si elemental abundance ratios to study the nature of the possible planets formed. We separated the planetary population in low-mass planets (<30M_{sun}_) and high-mass planets (>30M_{sun}_) to test for a possible relation with the mass. We find a diversity of mineralogical ratios that reveal the different kinds of planetary systems that can be formed, most of them dissimilar to our solar system. The different values of the Mg/Si and C/O can determine different composition of planets formed. {We found that 100% of our planetary sample present C/O<0.8. 86% of stars with high-mass companions present 0.8>C/O>0.4, while 14% present C/O values lower than 0.4. Regarding Mg/Si, all stars with low-mass planetary companion showed values between one and two, while 85% of the high-mass companion sample does. The other 15% showed Mg/Si values below one. No stars with planets were found with Mg/Si>2. Planet hosts with low-mass companions present C/O and Mg/Si similar to those found in the Sun, whereas stars with high-mass companions have lower C/O.
3409. CPASJ2 catalogue
ID:
ivo://CDS.VizieR/J/A+AS/136/1
Title:
CPASJ2 catalogue
Short Name:
J/A+AS/136/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
According to the cooperation between Beijing, San Juan and La Plata Astronomical Observatories, the photoelectric astrolabe Mark II(PAII) of the Beijing Astronomical Observatory was moved and installed at the San Juan Observatory, Argentina in January, 1992 for observations of the catalogue of stars in the southern hemisphere. The first observing period was from Feb. 23, 1992 to Mar. 31, 1997. Using the data observed in San Juan with the instrument during this period, residuals for 11002 stars are reduced from about 405700 observations of stars over 1532 days. The mean precision of the residuals is +/-0.043". The Second Catalogue of Stars (CPASJ2) has been compiled from double transits at both the eastern and western passages. There are 5241 stars in this catalogue, including 1225 FK5/FK4Supp stars, 794 FK5Ext stars, 1084 SRS stars, 937 CAMC4 stars, 310 GC stars and 891 IMF stars. The mean precisions are +/-3.2ms and +/-0.057" in right ascension and declination, respectively. The magnitudes of stars are from 2.0 to 11.5. The declinations are from -3{deg} to -60{deg}. The mean epoch is 1994.9. Finally, systematic corrections of(CPASJ2-FK5) are given.
3410. CPASJ1 catalogue
ID:
ivo://CDS.VizieR/J/A+AS/118/1
Title:
CPASJ1 catalogue
Short Name:
J/A+AS/118/1
Date:
21 Oct 2021
Publisher:
CDS
Description:
On the basis of the data observed with the photoelectric astrolabe Mark II(PA II) of Beijing Astronomical Observatory in San Juan of Argentina from Feb. 23, 1992 to Feb. 28, 1995, residuals of 7200 stars are reduced according to about 230000 observations of stars. The mean precision of the residuals is +/-0.046". Using the data, the first catalogue of stars (CPASJ1) have been compiled. There are 2980 stars in this catalogue included 989 FK5/FK4Supp stars, 658 FK5Ext stars, 387 SRS stars, 687 CAMC4 stars, 192 GC stars, and 72 Hipparcos stars. The mean precisions are +/-3.2ms and +/-0.061" in right ascensions and declinations, respectively. The magnitudes of stars are from 2mag to 11.3mag. The declinations are from -3deg to -60deg. The mean epoch is 1993.6. Finally, systematic corrections of(CPASJ1-FK5) are given.

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