- ID:
- ivo://CDS.VizieR/J/AJ/155/68
- Title:
- Elemental abundances of KOIs in APOGEE. I.
- Short Name:
- J/AJ/155/68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Apache Point Observatory Galactic Evolution Experiment (APOGEE) has observed ~600 transiting exoplanets and exoplanet candidates from Kepler (Kepler Objects of Interest, KOIs), most with >=18 epochs. The combined multi-epoch spectra are of high signal-to-noise ratio (typically >=100) and yield precise stellar parameters and chemical abundances. We first confirm the ability of the APOGEE abundance pipeline, ASPCAP, to derive reliable [Fe/H] and effective temperatures for FGK dwarf stars - the primary Kepler host stellar type - by comparing the ASPCAP-derived stellar parameters with those from independent high-resolution spectroscopic characterizations for 221 dwarf stars in the literature. With a sample of 282 close-in (P<100 days) KOIs observed in the APOGEE KOI goal program, we find a correlation between orbital period and host star [Fe/H] characterized by a critical period, P_crit_=8.3_-4.1_^+0.1^ days, below which small exoplanets orbit statistically more metal-enriched host stars. This effect may trace a metallicity dependence of the protoplanetary disk inner radius at the time of planet formation or may be a result of rocky planet ingestion driven by inward planetary migration. We also consider that this may trace a metallicity dependence of the dust sublimation radius, but we find no statistically significant correlation with host T_eff_ and orbital period to support such a claim.
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Search Results
- ID:
- ivo://CDS.VizieR/J/BaltA/14/51
- Title:
- Elemental abundances of 4 Lac and nu Cep
- Short Name:
- J/BaltA/14/51
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Elemental abundance analysis based on high S/N and high resolution Dominion Astrophysical Observatory spectrograms have been performed for two early type supergiants: 4 Lac (B9 Iab) and {nu} Cep (A2 Ia). Lines as weak as of order 5m{AA} are employed in this study. The projected rotational velocities of these stars are 14 and 26km/s, respectively. Both stars show similar radial velocity amplitudes, macroturbulent velocities and the same general elemental abundance trends. Their He, CNO and light element abundances are solar or overabundant while the iron peak and heavy element abundances are solar or underabundant. Detailed LTE model atmosphere abundance analysis shows that 4 Lac has nuclearly processed matter in its photosphere while {nu} Cep does not.
- ID:
- ivo://CDS.VizieR/J/AJ/127/373
- Title:
- Elemental abundances of 3 red giants in Ter 7
- Short Name:
- J/AJ/127/373
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Chemical abundances in three giants in Terzan 7, a globular cluster associated with the Sagittarius dwarf galaxy, have been determined using high-resolution spectra obtained with the UVES spectrograph on the ESO 8.2m Kueyen telescope. We find the overall metallicity of the stars to be [Fe/H]=-0.61+/-0.07, which is slightly higher than that previously evaluated from photometry and used for the age determination of this cluster. This metallicity yields an age of about 6Gyr, which is slightly lower than derived from previous estimates. The relative abundance ratios of various chemical elements to iron lie between those of its host galaxy's metal-poor and metal-rich stars and reveal an intriguing similarity to the pattern seen in the Large Magellanic Cloud.
- ID:
- ivo://CDS.VizieR/J/ApJ/787/154
- Title:
- Elemental abundances of solar sibling candidates
- Short Name:
- J/ApJ/787/154
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dynamical information along with survey data on metallicity and in some cases age have been used recently by some authors to search for candidates of stars that were born in the cluster where the Sun formed. We have acquired high-resolution, high signal-to-noise ratio spectra for 30 of these objects to determine, using detailed elemental abundance analysis, if they could be true solar siblings. Only two of the candidates are found to have solar chemical composition. Updated modeling of the stars' past orbits in a realistic Galactic potential reveals that one of them, HD 162826, satisfies both chemical and dynamical conditions for being a sibling of the Sun. Measurements of rare-element abundances for this star further confirm its solar composition, with the only possible exception of Sm. Analysis of long-term high-precision radial velocity data rules out the presence of hot Jupiters and confirms that this star is not in a binary system. We find that chemical tagging does not necessarily benefit from studying as many elements as possible but instead from identifying and carefully measuring the abundances of those elements that show large star-to-star scatter at a given metallicity. Future searches employing data products from ongoing massive astrometric and spectroscopic surveys can be optimized by acknowledging this fact.
- ID:
- ivo://CDS.VizieR/J/AJ/159/46
- Title:
- Elemental abundances of 416 stars in 5 dSphs of M31
- Short Name:
- J/AJ/159/46
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep spectroscopy from Keck/DEIMOS (DEep Imaging Multi-Object Spectrograph) of Andromeda I, III, V, VII, and X, all of which are dwarf spheroidal satellites (dSphs) of M31. The sample includes 256 spectroscopic members across all five dSphs. We confirm previous measurements of the velocity dispersions and dynamical masses, and we provide upper limits on bulk rotation. Our measurements confirm that M31 satellites obey the same relation between stellar mass and stellar metallicity as Milky Way (MW) satellites and other dwarf galaxies in the Local Group. The metallicity distributions show trends with stellar mass that are similar to those of MW satellites, including evidence in massive satellites for external influence, like pre-enrichment or gas accretion. We present the first measurements of individual element ratios, like [Si/Fe], in the M31 system, as well as measurements of the average [{alpha}/Fe] ratio. The trends of [{alpha}/Fe] with [Fe/H] also follow the same galaxy mass-dependent patterns as MW satellites. Less massive galaxies have more steeply declining slopes of [{alpha}/Fe] that begin at lower [Fe/H]. Finally, we compare the chemical evolution of M31 satellites to M31's Giant Stellar Stream and smooth halo. The properties of the M31 system support the theoretical prediction that the inner halo is composed primarily of massive galaxies that were accreted early. As a result, the inner halo exhibits higher [Fe/H] and [{alpha}/Fe] than surviving satellite galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/406/987
- Title:
- Elemental abundances of three CP stars
- Short Name:
- J/A+A/406/987
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We used data from the EBASIM spectrograph of the 2.1-m CASLEO telescope to study three rather sharp-lined late B to early A stars {xi} Oct (B6 IV), {alpha} Sex (B9.5 III), and 68 Tau (A2 IV). These measurements are compared with those from the Anglo-Austrialian Telescope for the first star and to those from the coude spectrograph of the 1.22-m telescope of the Dominion Astrophysical Observatory (DAO) for the other two stars. The equivalent width scales of the EBASIM and the DAO data are similar. Thus for the latter two stars the DAO data is also used in the analyses. Both {xi} Oct and {alpha} Sex generally have abundances close to those of the Sun in the range of values found for other normal stars with similar effective temperatures. The abundance pattern for 68 Tau is that of a metallic-lined star as is well known.
- ID:
- ivo://CDS.VizieR/J/ApJ/811/78
- Title:
- Elemental depletions in the Magellanic Clouds
- Short Name:
- J/ApJ/811/78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a study of the composition of gas and dust in the Large and Small Magellanic Clouds (LMC and SMC) using UV absorption spectroscopy. We measure PII and FeII along 84 spatially distributed sightlines toward the MCs using archival Far Ultraviolet Spectroscopic Explorer observations. For 16 of those sightlines, we also measure SiII, CrII, and ZnII from new Hubble Space Telescope Cosmic Origins Spectrograph observations. We analyze these spectra using a new spectral line analysis technique based on a semi-parametric Voigt profile model. We have combined these measurements with HI and H_2_ column densities and reference stellar abundances from the literature to derive gas-phase abundances, depletions, and gas-to-dust ratios (GDRs). Of our 84 P and 16 Zn measurements, 80 and 13, respectively, are depleted by more than 0.1dex, suggesting that P and Zn abundances are not accurate metallicity indicators at and above the metallicity of the SMC. Si, Cr, and Fe are systematically less depleted in the SMC than in the Milky Way (MW) or LMC. The minimum Si depletion in the SMC is consistent with zero. We find GDR ranges of 190-565 in the LMC and 480-2100 in the SMC, which is broadly consistent with GDRs from the literature. These ranges represent actual location to location variation and are evidence of dust destruction and/or growth in the diffuse neutral phase of the interstellar medium. Where they overlap in metallicity, the gas-phase abundances of the MW, LMC, and SMC and damped Ly{alpha} systems evolve similarly with metallicity.
- ID:
- ivo://CDS.VizieR/J/other/IBVS/5480
- Title:
- Elements for 80 eclipsing binaries
- Short Name:
- J/other/IBVS/548
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This research presents new elements for 80 eclipsing binaries found with the help of the ASAS-3, Hipparcos and TASS databases.
- ID:
- ivo://CDS.VizieR/J/other/IBVS/5495
- Title:
- Elements for 80 eclipsing binaries. II.
- Short Name:
- J/other/IBVS/549
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This research presents new elements for 80 eclipsing binaries found with the help of the ASAS-3, Hipparcos and TASS databases.
- ID:
- ivo://CDS.VizieR/J/other/IBVS/5542
- Title:
- Elements of southern eclipsing binaries
- Short Name:
- J/other/IBVS/554
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A set of 442 eclipsing binaries was selected from the GCVS catalog (Kholopov et al., 2003) that had declination <0{deg}, minimum magnitude brighter than 13.0, and no published times of minima later than JD 2440000 available through the NASA ADS service. An automated web-based data gathering application was developed to retrieve and display data from the ASAS-3 database (Pojmanski, 2002, Cat. J/AcA/48/35>). A search radius of 45 arcsec was used when selecting candidate stars.