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- ID:
- ivo://CDS.VizieR/J/A+A/469/L43
- Title:
- Radial velocities of Gl 581
- Short Name:
- J/A+A/469/L43
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This Letter reports on the detection of two super-Earth planets in the Gl 581 system, which is already known to harbour a hot Neptune. One of the planets has a mass of 5M_{earth}_ and resides at the "warm" edge of the habitable zone of the star. It is thus the known exoplanet that most resembles our own Earth. The other planet has a 7.7M_{earth}_ mass and orbits at 0.25AU from the star, close to the "cold" edge of the habitable zone. These two new light planets around an M3 dwarf further confirm the formerly tentative statistical trend toward (i) many more very low-mass planets being found around M dwarfs than around solar-type stars and (ii) low-mass planets outnumbering Jovian planets around M dwarfs.
- ID:
- ivo://CDS.VizieR/J/PASP/111/1233
- Title:
- Radial Velocities of Globular Cluster Giants
- Short Name:
- J/PASP/111/1233
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Velocities are given for 303 giant stars in the globular clusters M3, M13, M15, and M92 from spectra obtained with the 3.5-m WIYN Telescope at the Kitt Peak National Observatory using the Hydra multi-fiber positioner and bench spectrograph. The tables provide the individual identifications, HJD, and velocity for each star observed. The uncertainties in the velocity measurements are typically 1 km.s^-1^ or less.
- ID:
- ivo://CDS.VizieR/J/A+A/526/A112
- Title:
- Radial velocities of HARPS metal-poor sample
- Short Name:
- J/A+A/526/A112
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Searching for extrasolar planets around stars of different metallicity may provide strong constraints to the models of planet formation and evolution. In this paper we present the overall results of a HARPS (a high-precision spectrograph mostly dedicated to deriving precise radial velocities) program to search for planets orbiting a sample of 104 metal-poor stars (selected [Fe/H] below -0.5). Radial velocity time series of each star are presented and searched for signals using several statistical diagnostics. tars with detected signals are presented, including 3 attributed to the presence of previously announced giant planets orbiting the stars HD171028, HD181720, and HD190984. Several binary stars and at least one case of a coherent signal caused by activity-related phenomena are presented. One very promising new, possible giant planet orbiting the star HD107094 is discussed, and the results are analyzed in light of the metallicity-giant planet correlation. We conclude that the frequency of giant planets orbiting metal-poor stars may be higher than previously thought, probably reflecting the higher precision of the HARPS survey. In the metallicity domain of our sample, we also find evidence that the frequency of planets is a steeply rising function of the stellar metal content, as found for higher metallicity stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/723/L223
- Title:
- Radial velocities of HAT-P-11
- Short Name:
- J/ApJ/723/L223
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We find the orbit of the Neptune-sized exoplanet HAT-P-11b to be highly inclined relative to the equatorial plane of its host star. This conclusion is based on spectroscopic observations of two transits, which allowed the Rossiter-McLaughlin effect to be detected with an amplitude of 1.5m/s. The sky-projected obliquity is 103^+26^_-10_deg. This is the smallest exoplanet for which spin-orbit alignment has been measured. The result favors a migration scenario involving few-body interactions followed by tidal dissipation. This finding also conforms with the pattern that the systems with the weakest tidal interactions have the widest spread in obliquities. We predict that the high obliquity of HAT-P-11 will be manifest in transit light curves from the Kepler spacecraft: starspot-crossing anomalies will recur at most once per stellar rotation period, rather than once per orbital period as they would for a well-aligned system.
- ID:
- ivo://CDS.VizieR/J/ApJ/772/80
- Title:
- Radial velocities of HAT-P-17
- Short Name:
- J/ApJ/772/80
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the measured projected obliquity -the sky-projected angle between the stellar spin axis and orbital angular momentum- of the inner planet of the HAT-P-17 multi-planet system. We measure the sky-projected obliquity of the star to be {lambda}=19_-16_^+14^deg by modeling the Rossiter-McLaughlin effect in Keck/HIRES radial velocities (RVs). The anomalous RV time series shows an asymmetry relative to the midtransit time, ordinarily suggesting a nonzero obliquity -but in this case at least part of the asymmetry may be due to the convective blueshift, increasing the uncertainty in the determination of {lambda}. We employ the semi-analytical approach of Hirano et al. (2011ApJ...742...69H) that includes the effects of macroturbulence, instrumental broadening, and convective blueshift to accurately model the anomaly in the net RV caused by the planet eclipsing part of the rotating star. Obliquity measurements are an important tool for testing theories of planet formation and migration. To date, the measured obliquities of ~50 Jovian planets span the full range, from prograde to retrograde, with planets orbiting cool stars preferentially showing alignment of stellar spins and planetary orbits. Our results are consistent with this pattern emerging from tidal interactions in the convective envelopes of cool stars and close-in planets. In addition, our 1.8yr of new RVs for this system show that the orbit of the outer planet is more poorly constrained than previously thought, with an orbital period now in the range of 10-36yr.
- ID:
- ivo://CDS.VizieR/J/PAZh/39/41
- Title:
- Radial velocities of HBHA 4705-03
- Short Name:
- J/PAZh/39/41
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Results of photometric and spectroscopic studies for the new eclipsing cataclysmic variable star HBHA 4705-03 with an orbital period of 0.1718 days are presented.
- ID:
- ivo://CDS.VizieR/J/AJ/150/169
- Title:
- Radial velocities of HD 6434
- Short Name:
- J/AJ/150/169
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The current goal of exoplanetary science is not only focused on detecting but characterizing planetary systems in hopes of understanding how they formed, evolved, and relate to the solar system. The Transit Ephemeris Refinement and Monitoring Survey (TERMS) combines both radial velocity (RV) and photometric data in order to achieve unprecedented ground-based precision in the fundamental properties of nearby, bright, exoplanet-hosting systems. Here we discuss HD 6434 and its planet, HD 6434b, which has a M_p_sini=0.44M_J_ mass and orbits every 22.0170 days with an eccentricity of 0.146. We have combined previously published RV data with new measurements to derive a predicted transit duration of ~6 hr, or 0.25 days, and a transit probability of 4%. Additionally, we have photometrically observed the planetary system using both the 0.9 and 1.0m telescopes at the Cerro Tololo Inter-American Observatory, covering 75.4% of the predicted transit window. We reduced the data using the automated TERMS Photometry Pipeline, developed to ensure consistent and accurate results. We determine a dispositive null result for the transit of HD 6434b, excluding the full transit to a depth of 0.9% and grazing transit due to impact parameter limitations to a depth of 1.6%.
- ID:
- ivo://CDS.VizieR/J/ApJ/662/602
- Title:
- Radial velocities of HD 110555
- Short Name:
- J/ApJ/662/602
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We develop a technique to measure radial velocities of stars from spectra that present four sets of lines. The algorithm is an extension of the two-dimensional cross-correlation method TODCOR to four dimensions. It computes the correlation of the observed spectrum against a combination of four templates with all possible shifts, and it also allows for the derivation of the light ratios of the components. After testing the algorithm and demonstrating its ability to measure Doppler shifts accurately even under conditions of heavy line blending, we apply it to the case of the quadruple-lined system HD 110555. The primary and secondary components of this previously known visual binary ({rho}~0.4") are each shown to be double-lined spectroscopic binaries with periods of 57 days and 76 days, respectively, making the system a hierarchical quadruple. The secondary in the 76 days subsystem contributes only 2.5% to the total light, illustrating the ability of the method to measure velocities of very faint components.
- ID:
- ivo://CDS.VizieR/J/A+A/395/885
- Title:
- Radial velocities of HD 553
- Short Name:
- J/A+A/395/885
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- HD 553 was discovered as an eclipsing binary by Hipparcos. Here, we present the first radial velocity curve for this system. It is found, that HD 553 is a double-lined spectroscopic binary. Despite the large luminosity difference, the two components of this system are of very similar mass. The primary, a K0-giant, fills a large fraction of its Roche-lobe. The secondary is, despite its very similar mass, still a late-type dwarf. The radial velocity curve allows to constrain several stellar and system parameters.
