- ID:
- ivo://CDS.VizieR/J/ApJ/801/69
- Title:
- Iron EWs for 21 giant star members of NGC3201
- Short Name:
- J/ApJ/801/69
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- NGC 3201 is a globular cluster suspected to have an intrinsic spread in the iron content. We re-analyzed a sample of 21 cluster stars observed with UVES-FLAMES at the Very Large Telescope and for which Simmerer et al. (2013ApJ...764L...7S) found a 0.4dex wide [Fe/H] distribution with a metal-poor tail. We confirmed that when spectroscopic gravities are adopted, the derived [Fe/H] distribution spans ~0.4dex. On the other hand, when photometric gravities are used, the metallicity distribution from Fe I lines remains large, while that derived from Fe II lines is narrow and compatible with no iron spread. We demonstrate that the metal-poor component claimed by Simmerer et al. (2013ApJ...764L...7S) is composed by asymptotic giant branch stars that could be affected by non-local thermodynamical equilibrium effects driven by iron overionization. This leads to a decrease of the Fe I abundance, while leaving the Fe II abundance unaltered. A similar finding has been already found in asymptotic giant branch stars of the globular clusters M5 and 47 Tucanae. We conclude that NGC 3201 is a normal cluster, with no evidence of intrinsic iron spread.
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- ID:
- ivo://CDS.VizieR/J/ApJ/722/1226
- Title:
- IR photometry in {lambda} Orionis cluster
- Short Name:
- J/ApJ/722/1226
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present IRAC/MIPS Spitzer Space Telescope observations of the solar-type and the low-mass stellar population of the young (~5Myr) {lambda} Orionis cluster. Combining optical and Two Micron All Sky Survey photometry, we identify 436 stars as probable members of the cluster. Given the distance (450pc) and the age of the cluster, our sample ranges in mass from 2M_{sun}_ to objects below the substellar limit. With the addition of the Spitzer mid-infrared data, we have identified 49 stars bearing disks in the stellar cluster. Using spectral energy distribution slopes, we place objects in several classes: non-excess stars (diskless), stars with optically thick disks, stars with "evolved disks" (with smaller excesses than optically thick disk systems), and "transitional disk" candidates (in which the inner disk is partially or fully cleared). The disk fraction depends on the stellar mass, ranging from ~6% for K-type stars (R_C_-J<2) to ~27% for stars with spectral-type M5 or later (R_C_-J>4). We confirm the dependence of disk fraction on stellar mass in this age range found in other studies. Regarding clustering levels, the overall fraction of disks in the {lambda} Orionis cluster is similar to those reported in other stellar groups with ages normally quoted as ~5Myr.
- ID:
- ivo://CDS.VizieR/J/A+A/585/A126
- Title:
- 3 irradiated and bloated hot Jupiters RV and phot.
- Short Name:
- J/A+A/585/A126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report on three new transiting hot Jupiter planets, discovered from the WASP surveys, which we combine with radial velocities from OHP/SOPHIE and Euler/CORALIE and photometry from Euler and TRAPPIST. The planets WASP-76b, WASP-82b, and WASP-90b are all inflated, with radii of 1.7-1.8R_Jup_. All three orbit hot stars, of type F5-F7, with orbits of 1.8-3.9d, and all three stars have evolved, post-main-sequence radii (1.7-2.2R_{sun}_). Thus the three planets fit a known trend of hot Jupiters that receive high levels of irradiation, as a result of their being highly inflated. We caution, though, about the presence of a selection effect, in that non-inflated planets around ~2R_{sun}_ post-MS stars can often produce transits too shallow to be detected by the ground-based surveys that have found the majority of transiting hot Jupiters.
- ID:
- ivo://CDS.VizieR/J/ApJS/226/11
- Title:
- IR spectroscopy of AGN & starbursts
- Short Name:
- J/ApJS/226/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A sample of 379 extragalactic sources is presented that has mid-infrared, high-resolution spectroscopy from the Spitzer Infrared Spectrograph (IRS) and also spectroscopy of the [CII]158{mu}m line from the Herschel Photodetector Array Camera and Spectrometer (PACS). The emission line profiles of [NeII]12.81{mu}m, [NeIII]15.55{mu}m, and [CII]158{mu}m are presented, and intrinsic line widths are determined (full width half maximum of Gaussian profiles after instrumental correction). All line profiles, together with overlays comparing the positions of PACS and IRS observations, are made available in the Cornell Atlas of Spitzer IRS Sources (CASSIS). Sources are classified from active galactic nucleus (AGN) to starburst based on equivalent widths of the 6.2{mu}m polycyclic aromatic hydrocarbon feature. It is found that intrinsic line widths do not change among classifications for [CII], with median widths of 207km/s for AGNs, 248km/s for composites, and 233km/s for starbursts. The [NeII] line widths also do not change with classification, but [NeIII] lines are progressively broader from starburst to AGN. A few objects with unusually broad lines or unusual redshift differences in any feature are identified.
- ID:
- ivo://CDS.VizieR/J/ApJ/872/43
- Title:
- IR spectroscopy of symbiotic stars. XII. V934 Her
- Short Name:
- J/ApJ/872/43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The X-ray symbiotic (SyXB) V934 Her = 4U1700+24 is an M giant-neutron star (NS) binary system. Employing optical and infrared radial velocities spanning 29yr combined with the extensive velocities in the literature, we compute the spectroscopic orbit of the M giant in that system. We determine an orbital period of 4391d, or 12.0yr, the longest for any SyXB and far longer than the 404 day orbit commonly cited for this system in the literature. In addition to the 12.0yr orbital period, we find a shorter period of 420 days, similar to the one previously found. Instead of orbital motion, we attribute this much shorter period to long secondary pulsation of the M3 III SRb variable. Our new orbit supports earlier work that concluded that the orbit is seen nearly pole-on, which is why X-ray pulsations associated with the NS have not been detected. We estimate an orbital inclination of 11.3{deg}+/-0.4{deg}. Arguments are made that this low inclination supports a pulsation origin for the 420 day secondary period. We also measure the CNO and Fe peak abundances of the M giant and find it to be slightly metal-poor compared to the Sun, with no trace of the NS-forming supernova event. The basic properties of the M giant and NS are derived. We discuss the possible evolutionary paths that this system has taken to get to its current state.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/73.310
- Title:
- Isolated galaxy pair limited to M<=-18.5
- Short Name:
- J/other/AstBu/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The present paper is devoted to the construction of a catalog of isolated galaxy pairs extracted from the HyperLEDA extragalactic database. The radial velocities of the galaxies in the pairs are in the range [3000, 16000]km/s. In order to get an unbiased pair catalog as complete as possible, we have limited the absolute magnitude of the galaxies to M<=-18.5). The criteria used to define the isolated galaxy pairs are the following: 1) Velocity criterion: radial velocity difference between the pair members {Delta}V<500km/s; 2) Interdistance criterion: projected distance between the members r_p_<1Mpc; 3) Reciprocity criterion: each member is the closest galaxy to the other one, which excludes multiplets; 4) Isolation criterion: we define a pair as isolated if the ratio {rho}=r_3_/r_p_ of the projected distance of the pair to its closest galaxy (this one having a velocity difference lower than 500km/s with respect to the pair) and the members projected interdistance r_p is larger than 2.5. We have searched for these closest galaxies first in HyperLEDA M-limited source catalog, then in the full one. We have managed not to suppress the small number of pairs having close-by but faint dwarf galaxy companions. The galaxy pair catalog lists the value of {rho} for each isolated pair. This method allows the user of the catalog to select any isolation level (beyond the chosen limit {rho}>2.5). Our final catalog contains 13114 galaxy pairs, of which 57% are fairly isolated with {rho}>5, and 30% are highly isolated with {rho}>=10.
- ID:
- ivo://CDS.VizieR/J/ApJS/136/631
- Title:
- IUE absorption toward 164 early-type stars
- Short Name:
- J/ApJS/136/631
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present measurements of Galactic interstellar AlIII, SiIV, and CIV absorption recorded in high-resolution archival ultraviolet spectra of 164 hot early-type stars observed by the International Ultraviolet Explorer (IUE) satellite. The objects studied were drawn from the list of hot stars scheduled to be observed with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite as part of observing programs designed to investigate absorption by OVI in the Galactic disk and halo. Multiple IUE echelle-mode integrations have been combined to produce a single ultraviolet (1150-1900{AA}) spectrum of each star with a spectral resolution of ~25km/s (FWHM). Selected absorption-line profiles are presented for each star along with plots of the apparent column density per unit velocity for each line of the AlIII, SiIV, and CIV doublets. We report absorption-line equivalent widths, absorption velocities, and integrated column densities based on the apparent optical depth method of examining interstellar absorption lines. We also determine column densities and Doppler parameters from single-component curve-of-growth analyses. The scientific analysis of these observations will be undertaken after the FUSE satellite produces similar measurements for absorption by interstellar OIV, FeIII, SIII, and other ions.
- ID:
- ivo://CDS.VizieR/J/AJ/149/125
- Title:
- Iybvu photometry and CCD spectroscopy of RX Gem
- Short Name:
- J/AJ/149/125
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We obtained full-orbit Iybvu intermediate-band photometry and CCD spectroscopy of the long-period Algol eclipsing binary RX Geminorum. Photometric solutions using the Wilson-Devinney code give a gainer rotation (hotter, mass-accreting component) about 15 times the synchronous rate. We describe a simple technique to detect departures from uniform rotation of the hotter component. These binaries radiate double-peaked H{alpha} emission from a low-mass accretion disk around the gainer. We used an approximate non-LTE disk code to predict models in fair agreement with observations, except in the far wings of the emission profile, where the star-inner disk boundary layer emits extra radiation. Variations in H{alpha} emission derive from modulations in the transfer rate. A study of times of minima during the 20th century suggests that a perturbing third body is present near RX Gem.
- ID:
- ivo://CDS.VizieR/J/AJ/152/182
- Title:
- iz follow-up photometry of HAT-P-65 and HAT-P-66
- Short Name:
- J/AJ/152/182
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the discovery of the transiting exoplanets HAT-P-65b and HAT-P-66b, with orbital periods of 2.6055 and 2.9721 days, masses of 0.527+/-0.083M_J_ and 0.783+/-0.057M_J_, and inflated radii of 1.89+/-0.13R_J_ and 1.59_-0.10_^+0.16^R_J_, respectively. They orbit moderately bright (V=13.145+/-0.029 and V=12.993+/-0.052) stars of mass 1.212+/-0.050M_{Sun}_ and 1.255_-0.054_^+0.107^M_{Sun}_. The stars are at the main-sequence turnoff. While it is well known that the radii of close-in giant planets are correlated with their equilibrium temperatures, whether or not the radii of planets increase in time as their hosts evolve and become more luminous is an open question. Looking at the broader sample of well-characterized close-in transiting giant planets, we find that there is a statistically significant correlation between planetary radii and the fractional ages of their host stars, with a false-alarm probability of only 0.0041%. We find that the correlation between the radii of planets and the fractional ages of their hosts is fully explained by the known correlation between planetary radii and their present-day equilibrium temperatures; however, if the zero-age main-sequence equilibrium temperature is used in place of the present-day equilibrium temperature, then a correlation with age must also be included to explain the planetary radii. This suggests that, after contracting during the pre-main-sequence, close-in giant planets are reinflated over time due to the increasing level of irradiation received from their host stars. Prior theoretical work indicates that such a dynamic response to irradiation requires a significant fraction of the incident energy to be deposited deep within the planetary interiors.
- ID:
- ivo://CDS.VizieR/J/A+A/479/141
- Title:
- Iz photometry, RV and EW(Li) in IC 4665
- Short Name:
- J/A+A/479/141
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The so-called lithium depletion boundary (LDB) provides a secure and independent tool for deriving the ages of young open clusters. In this context, our goal is to determine membership for a sample of 147 photometrically selected candidates of the young open cluster IC 4665 and to use confirmed members to establish an age based on the LDB. Employing the FLAMES multi-object spectrograph on VLT/UT2, we have obtained intermediate-resolution spectra of the cluster candidates. The spectra were used to measure radial velocities and to infer the presence of the LiI 670.8nm doublet and H{alpha} emission.
