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- ID:
- ivo://CDS.VizieR/III/223
- Title:
- 12th General Catalogue of MK Spectral Classification
- Short Name:
- III/223
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the twelfth in a series of catalogs of MK spectral types and UBV photometry issued from Dearborn Observatory. It is based on an extensive search of literature published up to early 1995. Each catalog is essentially self-contained, with its separate selection of stars listed in order of increasing right ascension. Some classifications (indicated between parentheses) are inferred from photometric or astrometric considerations. The preferred identification is from the Henry Draper Catalog or the General Catalog of Variable Stars, with a Durchmusterung or other alternative as space permits.
- ID:
- ivo://CDS.VizieR/III/222
- Title:
- 14th General Catalogue of MK Spectral Classification
- Short Name:
- III/222
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the fourteenth in a series of catalogs of MK spectral types and UBV photometry issued from Dearborn Observatory. It is based on an extensive search of the literature published from ~1997 to 1999. Each catalog is essentially self-contained, with its separate selection of stars listed in order of increasing right ascension. Some classifications (indicated between parentheses) are inferred from photometric or astrometric considerations. The preferred identification is from the Henry Draper Catalog or the General Catalog of Variable Stars, with a Durchmusterung or other alternative as space permits.
- ID:
- ivo://CDS.VizieR/J/A+A/525/A90
- Title:
- Thick disc vertical properties
- Short Name:
- J/A+A/525/A90
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This work investigates the properties (metallicity and kinematics) and interfaces of the Galactic thick disc as a function of height above the Galactic plane. The main aim is to study the thick disc in a place where it is the main component of the sample. We take advantage of former astrometric work in two fields of several square degrees in which accurate proper motions were measured down to V-magnitudes of 18.5 in two directions, one near the north galactic pole and the other at a galactic latitude of 46{deg} and galactic longitude near 0{deg}. Spectroscopic observations have been acquired in these two fields for a total of about 400 stars down to magnitude 18.0, at spectral resolutions of 3.5 to 6.25{AA}. The spectra have been analysed with the code ETOILE, comparing the target stellar spectra with a grid of 1400 reference stellar spectra. This comparison allowed us to derive the parameters effective temperature, gravity, [Fe/H] and absolute magnitude for each target star.
- ID:
- ivo://CDS.VizieR/J/AJ/154/260
- Title:
- Three short-period eclipsing binaries BVRI photometry
- Short Name:
- J/AJ/154/260
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present new BVRI light curves of short-period contact eclipsing binaries V1101 Her and AD Phe from our observations carried out from 2014 to 2015 using the SARA KP and SARA CT telescopes. There is an eclipsing binary located at {alpha}(2000)=01h16m36.15s and {delta}(2000)=-39{deg}49'55.7" in the field of view of AD Phe. We derived an updated ephemeris and found there a cyclic variation overlaying a continuous period increase (V1101 Her) and decrease (AD Phe). This kind of cyclic variation may be attributed to the light time effect via the presence of the third body or magnetic activity cycle. The orbital period increase suggests that V1101 Her is undergoing a mass-transfer from the primary to the secondary component (dM_1_/dt=2.64(+/-0.11)x10^-6^ M_{sun}_/yr) with the third body (P3=13.9(+/-1.9) years), or 2.81(+/-0.07)x10^-6^ M_{sun}_/yr for an increase and magnetic cycle (12.4(+/-0.5) years). The long-term period decrease suggests that AD Phe is undergoing a mass-transfer from the secondary component to the primary component at a rate of -8.04(+/-0.09)x10^-8^ M_{sun}_/yr for a period decrease and the third body (P3=56.2(+/-0.8) years), or -7.11(+/-0.04)x10^-8^ M_{sun}_/yr for a decrease and magnetic cycle (50.3(+/-0.5) years). We determined their orbital and geometrical parameters. For AD Phe, we simultaneously analyzed our BVRI light curves and the spectroscopic observations obtained by Duerbeck & Rucinski (2007AJ....133..169D). The spectral type of V1101 Her was classified as G0+/-2V by LAMOST stellar spectra survey. The asymmetry of the R-band light curve of AD Phe obtained by McFarlane & Hilditch in 1987 (1987MNRAS.227..381M) is explained by a cool spot on the primary component.
- ID:
- ivo://CDS.VizieR/J/AJ/157/87
- Title:
- Times of minima for 21 early-type SMC eccentric EBs
- Short Name:
- J/AJ/157/87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the apsidal motion and light-curve analyses of 21 eccentric eclipsing binaries located in the Small Magellanic Cloud. Most of these systems have never been studied before, hence their orbital and physical properties as well as the apsidal motion parameters are given here for the first time. All the systems are of early spectral type, having orbital periods up to 4 days. The apsidal motion periods were derived to be from 7.2 to 200 yr (OGLE-SMC-ECL-2194 having the shortest apsidal period among known main-sequence systems). The orbital eccentricities are usually rather mild (median of about 0.06), the maximum eccentricity being 0.33. For the period analysis using O-C diagrams of eclipse timings, in total 951 minima were derived from survey photometry as well as our new data. Moreover, six systems show some additional variation in their O-C diagrams, which should indicate the presence of hidden additional components in them. According to our analysis these third-body variations have periods from 6.9 to 22 yr.
- ID:
- ivo://CDS.VizieR/J/AJ/153/258
- Title:
- 2007.5 to 2010.4 HST astrometry of HD 202206
- Short Name:
- J/AJ/153/258
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using Hubble Space Telescope Fine Guidance Sensor astrometry and previously published radial velocity measures, we explore the exoplanetary system HD202206. Our modeling results in a parallax, {pi}_abs_=21.96+/-0.12 milliseconds of arc, a mass for HD202206B of M_B_=0.089_-0.006_^+0.007M_{Sun}_, and a mass for HD202206c of M_c_=17.9_-1.8_^+2.9^M_Jup_. HD202206 is a nearly face-on G + M binary orbited by a brown dwarf. The system architecture that we determine supports past assertions that stability requires a 5:1 mean motion resonance (we find a period ratio, P_c_/P_B_=4.92+/-0.04) and coplanarity (we find a mutual inclination, {Phi}=6{deg}+/-2{deg}).
- ID:
- ivo://CDS.VizieR/J/AJ/159/150
- Title:
- Transit times of 11 hot Jupiters
- Short Name:
- J/AJ/159/150
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Many of the known hot Jupiters are formally unstable to tidal orbital decay. The only hot Jupiter for which orbital decay has been directly detected is WASP-12, for which transit-timing measurements spanning more than a decade have revealed that the orbital period is decreasing at a rate of dP/dt~10^-9^, corresponding to a reduced tidal quality factor of about 2x10^5^. Here, we present a compilation of transit-timing data for WASP-12 and 11 other systems that are especially favorable for detecting orbital decay: KELT-16; WASP-18, 19, 43, 72, 103, 114, and 122; HAT-P-23; HATS-18; and OGLE-TR-56. For most of these systems we present new data that extend the time baseline over which observations have been performed. None of the systems besides WASP-12 display convincing evidence for period changes, with typical upper limits on dP/dt on the order of 10^-9^ or 10^-10^, and lower limits on the reduced tidal quality factor on the order of 10^5^. One possible exception is WASP-19, which shows a statistically significant trend, although it may be a spurious effect of starspot activity.
- ID:
- ivo://CDS.VizieR/J/ApJ/717/1067
- Title:
- Triggered star formation in SFO 38
- Short Name:
- J/ApJ/717/1067
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have investigated the young stellar population in and around SFO 38, one of the massive globules located in the northern part of the Galactic HII region IC 1396, using the Spitzer IRAC and MIPS observations (3.6-24um), and followed up with ground-based optical photometric and spectroscopic observations. Based on the IRAC and MIPS colors and H{alpha} emission, we identify ~45 young stellar objects (Classes 0/I/II) and 13 probable pre-main-sequence candidates. We derive the spectral types (mostly K- and M-type stars), effective temperatures, and individual extinction of the relatively bright and optically visible Class II objects. Using the width of the H{alpha} emission line measured at 10% peak intensity, we derive the mass accretion rates of individual objects to be between 10^-10^ and 10^-8^M_{sun}_/yr.
- ID:
- ivo://CDS.VizieR/J/AJ/127/2915
- Title:
- Triple systems (cool primary + hot binary)
- Short Name:
- J/AJ/127/2915
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the course of comparing parameters of evolved cool star plus hot main-sequence star binaries with theoretical isochrones, some discrepancies are found between implied stellar masses and the spectroscopic binary mass function or the measured angular separation. These are naturally explained if there is a third star in the system. Multiplicity is also required to explain some comparisons of "cool plus hot binary" IUE and optical spectral energy distribution analysis with measured flux ratios, especially Tycho's two-color photometry of separate components. Out of a sample of 136 cool-plus-hot binary star systems under study, measurements are now indicating several systems considered double (HD 5373, 23089, 26673, 29094, 49126, 71129, 149379, 179002, 187299), and probably a few others (including HD 136415), to have at least three stellar components. Several other cases of suspected triple systems are confirmed. For comparison, there are eight known triples included in the project. In all, about 25% of the systems contain three or more components within a few arcseconds. Estimated separations are provided, which may be of use when not known from interferometry. In general, the triple systems have one post-main-sequence component and two upper main-sequence components, usually revolving around each other. One new triple system, HD 149379, has as its middle component an F giant in the brief first crossing of the Hertzsprung gap.
