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- ID:
- ivo://CDS.VizieR/J/A+A/510/A21
- Title:
- Stellar Limb-Darkening Coefficients
- Short Name:
- J/A+A/510/A21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Transiting exoplanets provide unparalleled access to the fundamental parameters of both extrasolar planets and their host stars. We present limb-darkening coefficients (LDCs) for the exoplanet hunting CoRot and Kepler missions. The LDCs are calculated with ATLAS stellar atmospheric model grids and span a wide range of T_eff_, logg, and metallically [M/H]. Both CoRot and Kepler use wide nonstandard photometric filters, and are producing a large inventory of high- quality transiting lightcurves, sensitive to stellar limb darkening. Comparing the stellar model limb darkening to results from the first seven CoRot planets, we find better fits are found when two model intensities at the limb are excluded in the coefficient calculations. This calculation method can help to avoid a major deficiency present at the limbs of the 1D stellar models.
- ID:
- ivo://CDS.VizieR/J/A+A/430/1143
- Title:
- Stellar magnetic rotational phase curves
- Short Name:
- J/A+A/430/1143
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Magnetized stars usually exhibit periodic variations of the effective (longitudinal) magnetic field B_e_ caused by their rotation. We present a catalog of magnetic rotational phase curves, B_e_ vs. the rotational phase phi, and tables of their parameters for 136 stars on the main sequence and above it. Phase curves were obtained by the least squares fitting of sine wave or double wave functions to the available B_e_ measurements, which were compiled from the existing literature. Most of the catalogued objects are chemically peculiar A and B type stars (127 stars). For some stars we also improved or determined periods of their rotation. We discuss the distribution of parameters describing magnetic rotational phase curves in our sample.
- ID:
- ivo://CDS.VizieR/J/A+A/652/A31
- Title:
- Stellar magnetic rotational phase curves. II
- Short Name:
- J/A+A/652/A31
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Some stars show periodic variability of the longitudinal (effective) global magnetic field B_e_ mainly due to rotation. We present the second version of the catalog of average magnetic phase curves, which are functions of B_e_ versus the rotational phase phi, tables of their parameters. The curves were obtained from literary data and as the result of observations from SAO RAS telescopes. A total of 357 stars of various spectral types were studied, data on which was published before the end of August 2020. Magnetic Ap and Bp stars make up the most numerous a subset in the catalog (224 objects). Phase curves were obtained by least squares fit of a simple sine wave or a double sine wave to the available B_e measurements. For some stars we also improved or determined periods of their rotation. Phase curves also are presented in 514 figures. In some cases several phase curves presented here correspond to the same star. This occurred when different observational techniques produced significantly different series of B_e_ values for that star. In a few cases the rotational phase curves of the surface field, B_s_, are given for stars where longitudinal magnetic field data were not available.
- ID:
- ivo://CDS.VizieR/J/MNRAS/441/2361
- Title:
- Stellar magnetism, age and rotation
- Short Name:
- J/MNRAS/441/2361
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate how the observed large-scale surface magnetic fields of low-mass stars (~0.1-2M_{sun}_), reconstructed through Zeeman-Doppler imaging, vary with age t, rotation and X-ray emission. Our sample consists of 104 magnetic maps of 73 stars, from accreting pre-main sequence to main-sequence objects (1Myr<~t<~10Gyr). For non-accreting dwarfs we empirically find that the unsigned average large-scale surface field is related to age as t^-0.655+/-0.045^. This relation has a similar dependence to that identified by Skumanich, used as the basis for gyrochronology. Likewise, our relation could be used as an age-dating method ('magnetochronology'). The trends with rotation we find for the large-scale stellar magnetism are consistent with the trends found from Zeeman broadening measurements (sensitive to large- and small-scale fields). These similarities indicate that the fields recovered from both techniques are coupled to each other, suggesting that small- and large-scale fields could share the same dynamo field generation processes. For the accreting objects, fewer statistically significant relations are found, with one being a correlation between the unsigned magnetic flux and rotation period. We attribute this to a signature of star-disc interaction, rather than being driven by the dynamo.
20696. Stellar Maser Observations
- ID:
- ivo://CDS.VizieR/V/68A
- Title:
- Stellar Maser Observations
- Short Name:
- V/68A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalog contains about 2958 stellar sources. For the searching of the maser emission of the sources listed, 368 were detected in H2O, 209 in SiO, and 713 in OH. In the catalog, one can find information about the stars including alternate names, the 1950 epoch position, velocity (LSR), spectral type, variability type, and period, as well as the references for both the detections and nondetections for each of the three molecules. In this catalog, Table 1 lists all the sources in right ascension order, Table 2 lists the references for all the maser observations for each source, and Table 3 lists the references in code order, i.e., in chronological order.
- ID:
- ivo://CDS.VizieR/J/ApJ/596/437
- Title:
- Stellar-mass black holes in the SDSS
- Short Name:
- J/ApJ/596/437
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We search for nearby, isolated, accreting, "stellar-mass" (3-100M_{sun}_) black holes. Models suggest a synchrotron spectrum in visible wavelengths and some emission in X-ray wavelengths. Of 3.7 million objects in the Sloan Digital Sky Survey Early Data Release, Cat. <J/AJ/123/567>, about 150,000 objects have colors and properties consistent with such a spectrum, and 87 of these objects are X-ray sources from the ROSAT All-Sky Survey (Cat. <IX/10> and <IX/29>). Thirty-two of these have been confirmed not to be black holes using optical spectra. We give the positions and colors of these 55 black hole candidates and quantitatively rank them on their likelihood to be black holes. We discuss uncertainties in the expected number of sources and the contribution of black holes to local dark matter.
20698. Stellar Mass Catalogue
- ID:
- ivo://CDS.VizieR/V/85A
- Title:
- Stellar Mass Catalogue
- Short Name:
- V/85A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalogue includes binary stars for which dynamical masses of components has been published in 1969 - 1988. It doesn't contain other compilation catalogues that was published in this two decades and uses original data papers only. It collects masses defined by direct, dynamical methods only (without use of mass-luminosity, mass-radius, mass-spectrum and similar relations). The work was supervised by Dr O. Malkov.
- ID:
- ivo://CDS.VizieR/J/MNRAS/504/3831
- Title:
- Stellar mass dist. of local star-forming gal.
- Short Name:
- J/MNRAS/504/3831
- Date:
- 18 Jan 2022 13:42:11
- Publisher:
- CDS
- Description:
- We constrain the mass distribution in nearby, star-forming galaxies with the Star Formation Reference Survey (SFRS), a galaxy sample constructed to be representative of all known combinations of star formation rate, dust temperature, and specific star formation rate (sSFR) that exist in the Local Universe. An innovative 2D bulge/disc decomposition of the 2MASS/Ks-band images of the SFRS galaxies yields global luminosity and stellar mass functions (MFs), along with separate MFs for their bulges and discs. These accurate MFs cover the full range from dwarf galaxies to large spirals, and are representative of star-forming galaxies selected based on their infrared luminosity, unbiased by active galactic nucleus content and environment. We measure an integrated luminosity density j=1.72+/-0.93x10^9^L_{sun}/h/Mpc^3^ and a total stellar mass density {rho}_M_=4.61+/-2.40x10^8^M_{sun}_/h/Mpc^3^. While the stellar mass of the average star-forming galaxy is equally distributed between its sub-components, discs globally dominate the mass density budget by a ratio 4:1 with respect to bulges. In particular, our functions suggest that recent star formation happened primarily in massive systems, where they have yielded a disc stellar mass density larger than that of bulges by more than 1 dex. Our results constitute a reference benchmark for models addressing the assembly of stellar mass on the bulges and discs of local (z=0) star-forming galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/867/108
- Title:
- Stellar masses and rest-frame u-g colors of SNIa
- Short Name:
- J/ApJ/867/108
- Date:
- 03 Dec 2021 00:48:50
- Publisher:
- CDS
- Description:
- Recent analyses suggest that distance residuals measured from Type Ia supernovae (SNe Ia) are correlated with local host galaxy properties within a few kiloparsecs of the SN explosion. However, the well-established correlation with global host galaxy properties is nearly as significant, with a shift of 0.06mag across a low to high mass boundary (the mass step). Here, with 273 SNe Ia at z<0.1, we investigate whether the stellar masses and rest-frame u-g colors of regions within 1.5kpc of the SN Ia explosion site are significantly better correlated with SN distance measurements than global properties or properties measured at random locations in SN hosts. At >~2{sigma} significance, local properties tend to correlate with distance residuals better than properties at random locations, though despite using the largest low-z sample to date, we cannot definitively prove that a local correlation is more significant than a random correlation. Our data hint that SNe observed by surveys that do not target a pre-selected set of galaxies may have a larger local mass step than SNe from surveys that do, an increase of 0.071+/-0.036mag (2.0{sigma}). We find a 3{sigma} local mass step after global mass correction, evidence that SNe Ia should be corrected for their local mass, but we note that this effect is insignificant in the targeted low-z sample. Only the local mass step remains significant at >2{sigma} after global mass correction, and we conservatively estimate a systematic shift in H0 measurements of -0.14km/s/Mpc with an additional uncertainty of 0.14km/s/Mpc, ~10% of the present uncertainty.