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- ID:
- ivo://CDS.VizieR/J/BaltA/10/589
- Title:
- Stars with large HIP photometric amplitudes
- Short Name:
- J/BaltA/10/589
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A list of the 2027 stars that have the largest photometric amplitudes in Hipparcos Photometry shows that the most variables stars are all Miras. The percentage of variable types change as a function of amplitude. This compilation should also be of value to photometrists looking for relatively unstudied, but large amplitude stars.
- ID:
- ivo://CDS.VizieR/J/A+A/535/A55
- Title:
- 4 stars with long-period planets
- Short Name:
- J/A+A/535/A55
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the discovery of four new long-period planets within the HARPS high-precision sample: HD137388b (Msini=0.22M_Jup_), HD204941b (Msini=0.27M_Jup_), HD7199b (Msini=0.29M_Jup_), HD7449b (Msini=1.04M_Jup_). A long-period companion, probably a second planet, is also found orbiting HD7449. Planets around HD137388, HD204941, and HD7199 have rather low eccentricities (less than 0.4) relative to the 0.82 eccentricity of HD7449b. All these planets were discovered even though their hosting stars have clear signs of activity.
- ID:
- ivo://CDS.VizieR/J/ApJ/825/62
- Title:
- Stars with M_p_sin(i)>0.1M_Jup_ hot Jupiter
- Short Name:
- J/ApJ/825/62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The origin of Jupiter-mass planets with orbital periods of only a few days is still uncertain. It is widely believed that these planets formed near the water-ice line of the protoplanetary disk, and subsequently migrated into much smaller orbits. Most of the proposed migration mechanisms can be classified either as disk-driven migration, or as excitation of a very high eccentricity followed by tidal circularization. In the latter scenario, the giant planet that is destined to become a hot Jupiter spends billions of years on a highly eccentric orbit, with apastron near the water-ice line. Eventually, tidal dissipation at periastron shrinks and circularizes the orbit. If this is correct, then it should be especially rare for hot Jupiters to be accompanied by another giant planet interior to the water-ice line. Using the current sample of giant planets discovered with the Doppler technique, we find that hot Jupiters with P_orb_<10d are no more or less likely to have exterior Jupiter-mass companions than longer-period giant planets with P_orb_>=10d. This result holds for exterior companions both inside and outside of the approximate location of the water-ice line. These results are difficult to reconcile with the high-eccentricity migration scenario for hot Jupiter formation.
- ID:
- ivo://CDS.VizieR/J/ApJ/743/48
- Title:
- Stars with rotation periods and X-ray luminosities
- Short Name:
- J/ApJ/743/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a sample of 824 solar and late-type stars with X-ray luminosities and rotation periods. This is used to study the relationship between rotation and stellar activity and derive a new estimate of the convective turnover time. From an unbiased subset of this sample the power law slope of the unsaturated regime, L_X_/L_{bol}_{propto}Ro^{beta}^, is fit as {beta}=-2.70+/-0.13. This is inconsistent with the canonical {beta}=-2 slope to a confidence of 5{sigma}, and argues for an additional term in the dynamo number equation. From a simple scaling analysis this implies {Delta}{Omega}/{Omega}{propto}{Omega}^0.7^, i.e. the differential rotation of solar-type stars gradually declines as they spin down. Super-saturation is observed for the fastest rotators in our sample and its parametric dependencies are explored. Significant correlations are found with both the corotation radius and the excess polar updraft, the latter theory providing a stronger dependence and being supported by other observations. We estimate mass-dependent empirical thresholds for saturation and super- saturation and map out three regimes of coronal emission. Late F-type stars are shown never to pass through the saturated regime, passing straight from super-saturated to unsaturated X-ray emission. The theoretical threshold for coronal stripping is shown to be significantly different from the empirical saturation threshold (Ro<0.13), suggesting it is not responsible. Instead we suggest that a different dynamo configuration is at work in stars with saturated coronal emission. This is supported by a correlation between the empirical saturation threshold and the time when stars transition between convective and interface sequences in rotational spin-down models.
- ID:
- ivo://idoc.d2s/corot/stars-rotation-period-affer-conesearch
- Title:
- Stars with rotation periods from Affer and al. IDOC D2S ConeSearch
- Short Name:
- CoRoT_N2_RotAff
- Date:
- 13 May 2019 17:27:59
- Publisher:
- IDOC D2S
- Description:
- Stars with rotation periods from Affer and al.
- ID:
- ivo://nasa.heasarc/rotxraycat
- Title:
- StarswithRotationPeriods&X-RayLuminositiesCatalog
- Short Name:
- ROTXRAYCAT
- Date:
- 09 May 2025
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This table contains photometric and derived stellar parameters for a sample of 820 solar and late-type stars (the original table of 824 entries had 4 near-duplicate entries for the stars HD 19668, HD 95188, HD 216803 and HD 285382 which have been removed by the HEASARC) from nearby open clusters and the field, including rotation periods and X-ray luminosities. This sample was used by the authors to study the relationship between rotation and stellar activity and derive a new estimate of the convective turnover time. From an unbiased subset of this sample the power law slope of the unsaturated regime, L<sub>X</sub>/L<sub>bol</sub> ~ R<sub>o</sub><sup>beta</sup>, is fit as beta = -2.70 +/- 0.13. This is inconsistent with the canonical beta = -2 slope to a confidence of 5 sigma, and argues for an additional term in the dynamo number equation. From a simple scaling analysis, this implies Delta(Omega)/Omega ~ Omega<sup>0.7</sup>, i.e. the differential rotation of solar-type stars gradually declines as they spin down. Super-saturation is observed for the fastest rotators in this sample and its parametric dependencies are explored. Significant correlations are found with both the corotation radius and the excess polar updraft, the latter theory providing a stronger dependence and being supported by other observations. The authors estimate mass-dependent empirical thresholds for saturation and super- saturation and map out three regimes of coronal emission. Late F-type stars are shown never to pass through the saturated regime, passing straight from super-saturated to unsaturated X-ray emission. The theoretical threshold for coronal stripping is shown to be significantly different from the empirical saturation threshold (R<sub>o</sub> < 0.13), suggesting it is not responsible. Instead, the authors suggest that a different dynamo configuration is at work in stars with saturated coronal emission. This is supported by a correlation between the empirical saturation threshold and the time when stars transition between convective and interface sequences in rotational spin-down models. This table was created by the HEASARC in March 2012 based on <a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/ApJ/743/48">CDS Catalog J/ApJ/743/48</a> file catalog.dat. The original table had 824 entries, including 4 near-duplicate entries for the stars HD 19668, HD 95188, HD 216803 and HD 285382, which have been removed by the HEASARC. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/A+A/627/A31
- Title:
- Statistial HATLAS Lensed Objects Selec.
- Short Name:
- J/A+A/627/A31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The statistical analysis of large sample of strong lensing events can be a powerful tool to extract astrophysical or cosmological valuable information. Their selection using submillimetre galaxies has been demonstrated to be very effective with more than ~200 proposed candidates in the case of Herschel-ATLAS data and several tens in the case of the South Pole Telescope. However, the number of confirmed events is still relatively low, i.e. a few tens, mostly because of the lengthy observational validation process on individual events. In this work we propose a new methodology with a statistical selection approach to increase by a factor of ~5 the number of such events within the Herschel-ATLAS data set. Although the methodology can be applied to address several selection problems, it has particular benefits in the case of the identification of strongly lensed galaxies: objectivity, minimal initial constrains in the main parameter space, and preservation of statistical properties. The proposed methodology is based on the Bhattacharyya distance as a measure of the similarity between probability distributions of properties of two different cross-matched galaxies. The particular implementation for the aim of this work is called SHALOS and it combines the information of four different properties of the pair of galaxies: angular separation, luminosity percentile, redshift, and the ratio of the optical to the submillimetre flux densities. The SHALOS method provides a ranked list of strongly lensed galaxies. The number of candidates within ~340{deg}^2^ of the Herschel-ATLAS surveyed area for the final associated probability, P_tot_>0.7, is 447 and they have an estimated mean amplification factor of 3.12 for a halo with a typical cluster mass. Additional statistical properties of the SHALOS candidates, as the correlation function or the source number counts, are in agreement with previous results indicating the statistical lensing nature of the selected sample.
- ID:
- ivo://CDS.VizieR/J/ApJ/794/159
- Title:
- Statistical analysis of exoplanet surveys
- Short Name:
- J/ApJ/794/159
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We conduct a statistical analysis of a combined sample of direct imaging data, totalling nearly 250 stars. The stars cover a wide range of ages and spectral types, and include five detections ({kappa} And b, two ~60 M_J_ brown dwarf companions in the Pleiades, PZ Tel B, and CD-35 2722B). For some analyses we add a currently unpublished set of SEEDS observations, including the detections GJ 504b and GJ 758B. We conduct a uniform, Bayesian analysis of all stellar ages using both membership in a kinematic moving group and activity/rotation age indicators. We then present a new statistical method for computing the likelihood of a substellar distribution function. By performing most of the integrals analytically, we achieve an enormous speedup over brute-force Monte Carlo. We use this method to place upper limits on the maximum semimajor axis of the distribution function derived from radial-velocity planets, finding model-dependent values of ~30-100 AU. Finally, we model the entire substellar sample, from massive brown dwarfs to a theoretically motivated cutoff at ~5 M_J_, with a single power-law distribution. We find that p(M,a){prop.to}M^-0.65+/-0.60^a^-0.85+/-0.39^ (1{sigma} errors) provides an adequate fit to our data, with 1.0%-3.1% (68% confidence) of stars hosting 5-70 M_J_ companions between 10 and 100 AU. This suggests that many of the directly imaged exoplanets known, including most (if not all) of the low-mass companions in our sample, formed by fragmentation in a cloud or disk, and represent the low-mass tail of the brown dwarfs.
- ID:
- ivo://CDS.VizieR/J/A+A/398/363
- Title:
- Statistical properties of exoplanets II
- Short Name:
- J/A+A/398/363
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table2 file is an extended version of table 2 in the paper. It contains the stellar parameters as well as the number of FeI and FeII lines used (and the rms around the mean value) in the analysis, the spectrograph used, and the derived stellar masses for each star. Velocity files contains the U, V, and W space velocities for the planet host stars used in Figs. 9 and 10.