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- ID:
- ivo://CDS.VizieR/J/ApJS/250/29
- Title:
- Search for nearby Earth analogs. III. RV sets
- Short Name:
- J/ApJS/250/29
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Earth-sized planets in the habitable zones of M dwarfs are good candidates for the study of habitability and detection of biosignatures. To search for these planets, we analyze all available radial velocity data and apply four signal detection criteria to select the optimal candidates. We find 10 strong candidates satisfying these criteria and three weak candidates showing inconsistency over time due to data samplings. We also confirm three previous planet candidates and improve their orbital solutions through combined analyses of updated data sets. Among the strong planet candidates, HIP38594b is a temperate super-Earth with a mass of 8.2+/-1.7M_{Earth}_ and an orbital period of 60.7+/-0.1 days, orbiting around an early-type M dwarf. Early-type M dwarfs are less active and thus are better hosts for habitable planets than mid-type and late-type M dwarfs. Moreover, we report the detection of five two-planet systems, including two systems made up of a warm or cold Neptune and a cold Jupiter, consistent with a positive correlation between these two types of planets. We also detect three temperate Neptunes, four cold Neptunes, and four cold Jupiters, contributing to a rarely explored planet population. Due to their proximity to the Sun, these planets on wide orbits are appropriate targets for direct imaging by future facilities such as the Habitable Exoplanet Observatory and the Extremely Large Telescope.
- ID:
- ivo://CDS.VizieR/J/ApJS/246/11
- Title:
- Search for nearby earth analogs. II. RV analysis.
- Short Name:
- J/ApJS/246/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Zechmeister et al. (2009, J/A+A/505/859) surveyed 38 nearby M dwarfs from 2000 to 2007 March with VLT2 and the Ultraviolet and Visual Echelle Spectrograph (UVES) spectrometer. These data have recently been reanalyzed, yielding a significant improvement in the Doppler velocity precision. Spurred by this, we have combined the UVES data with velocity sets from High Accuracy Radial velocity Planet Searcher, Magellan/Planet Finder Spectrograph, and Keck/High Resolution Echelle Spectrometer. Sixteen planet candidates have been uncovered orbiting nine M dwarfs. Five of them are new planets corresponding to radial velocity signals, which are not sensitive to the choice of noise models and are identified in multiple data sets over various time spans. Eight candidate planets require additional observation to be confirmed. We also confirm three previously reported planets. Among the new planets, GJ 180 d and GJ 229A c are super-Earths located in the conservative habitable zones of their host stars. We investigate their dynamical stability using the Monte Carlo approach and find both planetary orbits are robust to the gravitational perturbations of the companion planets. Due to their proximity to the Sun, the angular separation between the host stars and the potentially habitable planets in these two systems is 25 and 59 mas, respectively. They are thus good candidates for future direct imaging by James Webb Space Telescope and E-ELT. In addition, we find GJ 433 c, a cold super-Neptune belonging to an unexplored population of Neptune-like planets. With a separation of 0.5" from its host star, GJ 433 c is probably the first realistic candidate for the direct imaging of cold Neptunes. A comprehensive survey of these planets is important for the studies of planet formation.
- ID:
- ivo://CDS.VizieR/J/PASP/118/1656
- Title:
- Secondary velocity standards at NGP
- Short Name:
- J/PASP/118/1656
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present mean radial velocities for 143 stars in Selected Area 57 at the north Galactic pole that are suitable for use as secondary velocity standards. The stars were drawn from a magnitude-limited sample and are mostly fainter than 11th magnitude in V. They span a wide range of effective temperatures and surface gravities and thus provide a suitable source of targets for observed templates. The mean radial velocities are based on at least 10 observations spanning at least 8200 days, and are accurate typically to 0.2km/s, with no obvious signs of variable velocity or composite spectra.
- ID:
- ivo://CDS.VizieR/J/A+AS/147/187
- Title:
- Second list of the Karachentsev catalog
- Short Name:
- J/A+AS/147/187
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table2 presents the results of HI observations of 78 'nearby dwarf galaxies' from Karachentseva et al. (1999A&AS..135..221K) obtained with the 100-m radio telescope at Effelsberg. This survey covers an area limited by R.A.[14h,23h30] and Dec[-20d,+60d] including the nearest cosmic void : R.A.[18h38m], Dec[+18d], V_0_<1500km/s.
- ID:
- ivo://CDS.VizieR/J/AJ/142/88
- Title:
- Segue 3 photometric and kinematic data
- Short Name:
- J/AJ/142/88
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the kinematic and photometric properties of the Segue 3 Milky Way companion using Keck/DEIMOS spectroscopy and Magellan/IMACS g- and r-band imaging. Using maximum likelihood methods to analyze the photometry, we study the structure and stellar population of Segue 3. We find that the half-light radius of Segue 3 is 26"+/-5" (2.1+/-0.4pc, for a distance of 17kpc) and the absolute magnitude is a mere M_V_=0.0+/-0.8mag, making Segue 3 the least luminous old stellar system known.
- ID:
- ivo://CDS.VizieR/J/AJ/136/2050
- Title:
- SEGUE stellar parameter pipeline. II.
- Short Name:
- J/AJ/136/2050
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We validate the accuracy and precision of the current SEGUE (Sloan Extension for Galactic Understanding and Exploration) Stellar Parameter Pipeline (SSPP), which determines stellar atmospheric parameters (effective temperature, surface gravity, and metallicity) and radial velocities (RVs), by comparing these estimates for selected members of three globular clusters (M 13, M 15, and M 2) and two open clusters (NGC 2420 and M 67) to the literature values. Spectroscopic and photometric data obtained during the course of the original Sloan Digital Sky Survey (SDSS-I) and its first extension (SDSS-II/SEGUE) are used to determine atmospheric parameter and RV estimates for stars in these clusters.
- ID:
- ivo://CDS.VizieR/J/AJ/136/2070
- Title:
- SEGUE stellar parameter pipeline. III.
- Short Name:
- J/AJ/136/2070
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report high-resolution spectroscopy of 125 field stars previously observed as part of the Sloan Digital Sky Survey and its program for Galactic studies, the Sloan Extension for Galactic Understanding and Exploration (SEGUE). These spectra are used to measure radial velocities and to derive atmospheric parameters, which we compare with those reported by the SEGUE Stellar Parameter Pipeline (SSPP). The SSPP obtains estimates of these quantities based on SDSS ugriz photometry and low-resolution (R~2000) spectroscopy.
- ID:
- ivo://CDS.VizieR/J/AJ/141/89
- Title:
- SEGUE stellar parameter pipeline. IV.
- Short Name:
- J/AJ/141/89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Spectroscopic and photometric data for likely member stars of five Galactic globular clusters (M3, M53, M71, M92, and NGC 5053) and three open clusters (M35, NGC 2158, and NGC 6791) are processed by the current version of the SEGUE Stellar Parameter Pipeline (SSPP), in order to determine estimates of metallicities and radial velocities (RVs) for the clusters. These results are then compared to values from the literature.
- ID:
- ivo://CDS.VizieR/J/A+A/296/727
- Title:
- Semiregular variables H2O maser
- Short Name:
- J/A+A/296/727
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 107 semiregular variables of spectral type M have been observed in the H2O 6(16)-5(23) line at 22.235GHz with the 100m Effelsberg radio telescope and maser emission has been detected in 23 objects, of which 10 are new detections.
