- ID:
- ivo://CDS.VizieR/J/A+A/321/L33
- Title:
- Terrestrial impact cratering rate
- Short Name:
- J/A+A/321/L33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The most significant periodicities in the terrestrial impact crater record are due to the "human-signal": the bias of assigning integer values for the crater ages. This bias seems to have eluded the proponents and opponents of real periodicity in the occurrence of these events, as well as the theorists searching for an extraterrestrial explanation for such periodicity. The "human-signal" should be seriously considered by scientists in astronomy, geology and paleontology when searching for a connection between terrestrial major comet or asteroid impacts and mass extinctions of species.
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21442. Terrestrial impact craters
- ID:
- ivo://padc.obspm.planeto/terrestrial_impact_craters/q/epn_core
- Title:
- Terrestrial impact craters
- Short Name:
- terrestrial_impa
- Date:
- 26 Feb 2025 13:36:59
- Publisher:
- PADC
- Description:
- Terrestrial Impact Craters
- ID:
- ivo://CDS.VizieR/J/ApJ/809/8
- Title:
- Terrestrial planet occurrence rates for KOI stars
- Short Name:
- J/ApJ/809/8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We measure planet occurrence rates using the planet candidates discovered by the Q1-Q16 Kepler pipeline search. This study examines planet occurrence rates for the Kepler GK dwarf target sample for planet radii, 0.75<=Rp<=2.5R_{Earth}_, and orbital periods, 50<=Porb<=300days, with an emphasis on a thorough exploration and identification of the most important sources of systematic uncertainties. Integrating over this parameter space, we measure an occurrence rate of F_0_=0.77 planets per star, with an allowed range of 0.3<=F0<=1.9. The allowed range takes into account both statistical and systematic uncertainties, and values of F_0_ beyond the allowed range are significantly in disagreement with our analysis. We generally find higher planet occurrence rates and a steeper increase in planet occurrence rates toward small planets than previous studies of the Kepler GK dwarf sample. Through extrapolation, we find that the one year orbital period terrestrial planet occurrence rate {zeta}_1.0_=0.1, with an allowed range of 0.01<={zeta}_1.0_<=2, where {zeta}_1.0_ is defined as the number of planets per star within 20% of the Rp and Porb of Earth. For G dwarf hosts, the {zeta}_1.0_ parameter space is a subset of the larger {eta}_{Earth}_ parameter space, thus {zeta}_1.0_ places a lower limit on {eta}_{Earth}_ for G dwarf hosts. From our analysis, we identify the leading sources of systematics impacting Kepler occurrence rate determinations as reliability of the planet candidate sample, planet radii, pipeline completeness, and stellar parameters.
- ID:
- ivo://CDS.VizieR/J/AJ/144/62
- Title:
- Tertiary companions to close spectroscopic binaries
- Short Name:
- J/AJ/144/62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the first results of a multi-epoch search for wide (separations greater than a few tens of AU), low-mass tertiary companions of a volume-limited sample of 118 known spectroscopic binaries within 30pc of the Sun, using the Two Micron All Sky Survey Point Source Catalog and follow-up observations with the KPNO and CTIO 4m telescopes. Note that this sample is not volume complete but volume limited, and, thus, there is incompleteness in our reported companion rates. We are sensitive to common proper motion companions with separations from roughly 200AU to 10000AU (~10"-->~10'). From 77 sources followed-up to date, we recover 11 previously known tertiaries, 3 previously known candidate tertiaries, of which 2 are spectroscopically confirmed and 1 rejected, and 3 new candidates, of which 2 are confirmed and 1 rejected. This yields an estimated wide tertiary fraction of 19.5^+5.2^_-3.7_%. This observed fraction is consistent with predictions set out in star formation simulations where the fraction of wide, low-mass companions to spectroscopic binaries is >10%.
- ID:
- ivo://CDS.VizieR/J/ApJ/791/101
- Title:
- Terzan 5 chemical and kinematical properties
- Short Name:
- J/ApJ/791/101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of a study aimed at determining the kinematical and chemical properties of Terzan 5, we present the first characterization of the bulge stars surrounding this puzzling stellar system. We observed 615 targets located well beyond the tidal radius of Terzan 5 and found that their radial velocity distribution is well described by a Gaussian function peaked at <v_rad_> = +21.0+/-4.6 km/s with dispersion {sigma}_v_= 113.0+/-2.7 km/s. This is one of the few high-precision spectroscopic surveys of radial velocities for a large sample of bulge stars in such a low and positive latitude environment (b = +1.7{deg}). We found no evidence of the peak at <v_rad_> ~ +200 km/s found in Nidever et al. (2012ApJ...755L..25N). Strong contamination of many observed spectra by TiO bands prevented us from deriving the iron abundance for the entire spectroscopic sample, introducing a selection bias. The metallicity distribution was finally derived for a subsample of 112 stars in a magnitude range where the effect of the selection bias is negligible. The distribution is quite broad and roughly peaked at solar metallicity ([Fe/H] =~ +0.05 dex) with a similar number of stars in the super-solar and in the sub-solar ranges. The population number ratios in different metallicity ranges agree well with those observed in other low-latitude bulge fields, suggesting (1) the possible presence of a plateau for|b| < 4{deg} in the ratio between stars in the super-solar (0 < [Fe/H] <0.5 dex) and sub-solar (-0.5 < [Fe/H] <0 dex) metallicity ranges; (2) a severe drop in the metal-poor component ([Fe/H] <-0.5) as a function of Galactic latitude.
- ID:
- ivo://CDS.VizieR/J/A+AS/126/319
- Title:
- Terzan 10, ESO456-SC38 and UKS 1 VIz photometry
- Short Name:
- J/A+AS/126/319
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical colour-magnitude diagrams for the faint bulge globular clusters Terzan 10, ESO456-SC38 and UKS 1. The giant branches are detected but the horizontal branch is near the observational cutoff for the former two clusters and is not detected in UKS 1. We provide estimates of metallicity, reddening and distance for these clusters, some of these values determined for the first time.
21447. Terzan 6 NTT VI photometry
- ID:
- ivo://CDS.VizieR/J/A+AS/122/483
- Title:
- Terzan 6 NTT VI photometry
- Short Name:
- J/A+AS/122/483
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present for the first time optical (V, I and Gunn z) colour magnitude diagrams for Terzan 6, which were collected under excellent seeing conditions with the ESO NTT telescope. The horizontal branch morphology is red, nearly superimposed on the red giant branch. The red giant branch morphology presents characteristics intermediate between those of 47 Tuc and NGC 6528/NGC 6553. We derive a reddening of E(B-V)=2.24 and a distance d_{sun}_=7.0kpc (assuming R=3.1). We conclude that Terzan 6 belongs to the metal-rich bulge globular cluster system.
21448. Terzan 2 VI photometry
- ID:
- ivo://CDS.VizieR/J/A+A/326/614
- Title:
- Terzan 2 VI photometry
- Short Name:
- J/A+A/326/614
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present for the first time optical colour magnitude diagrams of the globular cluster Terzan 2, in the V, I colours. The horizontal branch is red. The red giant branch morphology can be fitted with that of 47 Tuc, but definitely not th at of NGC 6553. We derive a reddening of E(B-V)=1.54 and a distance d_{sun}_=7.7kpc if R=3.1, or 5.3kpc if R=3.6. Terzan 2 adds to the list of bulge metal-rich clusters now with reliable parameters.
21449. TESELA
- ID:
- ivo://svo.cab/tesela
- Title:
- TESELA
- Short Name:
- TESELA
- Date:
- 14 Mar 2019 08:20:45
- Publisher:
- SVO CAB
- Description:
- The most important advantage of widefield cameras is, precisely, the "widefield", since this offers the observers the possibility of obtaining vast amounts of data in a much shorter observing time. However, for a reliable data interpretation, it is necessary a proper data calibration. Concerning the flatfielding of images, many times it is required to obtain several integrations in blank regions (sky patches without bright sources) nearby to the science target areas. TESELA is a service developed to provide access to a catalogue of blank regions, based on the application of the Delaunay triangulation of the sky. The present implementation of TESELA uses as source for the star coordinates the Tycho-2 Catalogue (Hog et al. 2000). The system has been jointly developed by the Department of Astrophysics of the Universidad Complutense de Madrid and CAB (INTA-CSIC) and is maintained at CAB (INTA-CSIC). If you use TESELA in your research, please include the following acknowledgement in any resulting publications: "This publication makes use of TESELA, developed under the Spanish Virtual Observatory project supported from the Spanish MICINN through grant AyA2008-02156." "Partially funded by the Spanish MICINN under the Consolider-Ingenio 2010 Program grant CSD2006-00070: First Science with the GTC"
- ID:
- ivo://CDS.VizieR/J/ApJ/898/L11
- Title:
- TESS and NGTS LCs and RVs of NGTS-11
- Short Name:
- J/ApJ/898/L11
- Date:
- 30 Dec 2021 08:02:31
- Publisher:
- CDS
- Description:
- We report the discovery of NGTS-11 b (=TOI-1847b), a transiting Saturn in a 35.46 day orbit around a mid K-type star (T_eff_=5050+/-80K). We initially identified the system from a single-transit event in a TESS full-frame image light curve. Following 79 nights of photometric monitoring with an NGTS telescope, we observed a second full transit of NGTS-11 b approximately one year after the TESS single-transit event. The NGTS transit confirmed the parameters of the transit signal and restricted the orbital period to a set of 13 discrete periods. We combined our transit detections with precise radial-velocity measurements to determine the true orbital period and measure the mass of the planet. We find NGTS-11 b has a radius of 0.817_-0.032_^+0.028^R_Jup_, a mass of 0.344_-0.073_^+0.092^M_Jup_, and an equilibrium temperature of just 435_-32_^+34^K, making it one of the coolest known transiting gas giants. NGTS-11 b is the first exoplanet to be discovered after being initially identified as a TESS single-transit event, and its discovery highlights the power of intense photometric monitoring in recovering longer-period transiting exoplanets from single-transit events.
