- ID:
- ivo://CDS.VizieR/J/ApJ/842/120
- Title:
- Large spectrosc. survey of Palomar 5 stellar stream
- Short Name:
- J/ApJ/842/120
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present two spectroscopic surveys of the tidal stellar stream of the Palomar 5 globular cluster undertaken with the VLT/FLAMES and AAT/AAOmega instruments. We use these data in conjunction with photometric data presented in the previous contribution in this series to classify the survey stars in terms of their probability of belonging to the Palomar 5 stellar stream. We find that high-probability candidates are only found in a very narrow spatial interval surrounding the locus of the stream on the sky. PanSTARRS RRLyrae stars in this region of the sky are also distributed in a similar manner. The absence of significant "fanning" of this stellar stream confirms that Palomar 5 does not follow a chaotic orbit. Previous studies have found that Palomar 5 is largely devoid of low-mass stars, and we show that this is true also of the stellar populations along the trailing arm out to 6{deg}. Within this region, which contains 73% of the detected stars, the population is statistically identical to the core, implying that the ejection of the low-mass stars occurred before the formation of the stream. We also present an updated structural model fit to the bound remnant, which yields a total mass of 4297+/-98M_{sun}_ and a tidal radius 0.145+/-0.009kpc. We estimate the mass of the observed system including the stream to be 12200+/-400M_{sun}_, and the initial mass to have been ~47000+/-1500M_{sun}_.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/246/54
- Title:
- Late-type giants in Baade's window
- Short Name:
- J/MNRAS/246/54
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Radial velocities have been measured for an unbiased sample of 239 late-type M giants in the b=-4{deg} galactic bulge window (Baade's window). The radial velocities were acquired at the AAT Observatory.
- ID:
- ivo://CDS.VizieR/J/ApJ/809/42
- Title:
- LC and RV data of PTFO 8-8695 T-Tauri star
- Short Name:
- J/ApJ/809/42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Spitzer 4.5{mu}m light curve observations, Keck NIRSPEC radial velocity observations, and LCOGT optical light curve observations of PTFO 8-8695, which may host a Jupiter-sized planet in a very short orbital period (0.45 days). Previous work by van Eyken et al. (2012ApJ...755...42V) and Barnes et al. (2013ApJ...774...53B) predicts that the stellar rotation axis and the planetary orbital plane should precess with a period of 300-600 days. As a consequence, the observed transits should change shape and depth, disappear, and reappear with the precession. Our observations indicate the long-term presence of the transit events (>3 years), and that the transits indeed do change depth, disappear and reappear. The Spitzer observations and the NIRSPEC radial velocity observations (with contemporaneous LCOGT optical light curve data) are consistent with the predicted transit times and depths for the M*=0.34M_{sun}_ precession model and demonstrate the disappearance of the transits. An LCOGT optical light curve shows that the transits do reappear approximately 1 year later. The observed transits occur at the times predicted by a straight-forward propagation of the transit ephemeris. The precession model correctly predicts the depth and time of the Spitzer transit and the lack of a transit at the time of the NIRSPEC radial velocity observations. However, the precession model predicts the return of the transits approximately 1 month later than observed by LCOGT. Overall, the data are suggestive that the planetary interpretation of the observed transit events may indeed be correct, but the precession model and data are currently insufficient to confirm firmly the planetary status of PTFO 8-8695b.
- ID:
- ivo://CDS.VizieR/J/MNRAS/463/1707
- Title:
- l Car radial velocity curves
- Short Name:
- J/MNRAS/463/1707
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This work reports the discovery of cycle-to-cycle modulated spectral line and atmospheric velocity gradient variability in long-period Cepheids based on 925 high-resolution optical spectra of l Carinae (P~35.5d) recorded during three heavy duty-cycle monitoring campaigns (in 2014, 2015, and 2016). Spectral line variability is investigated via cross-correlation functions (CCFs) computed using three sets of spectral lines (weak, solar, strong). A metallic line velocity gradient, {delta}v_r_(t), is computed as the difference between weak and strong-line RVs. CCF shape indicators BIS (asymmetry), FWHM, and depth all exhibit clear phase-dependent variability patterns that differ from one pulsation cycle to the next. Weak-line CCFs exhibit these effects more clearly than strong-line CCFs. BIS exhibits the most peculiar modulated variability and can be used to identify the presence of cycle-to-cycle modulated line profile variations. {delta}v_r_(t) clearly exhibits cycle-to-cycle differences that correlate very closely with modulated BIS variability, suggesting perturbations of the atmospheric velocity field as the cause for modulated spectral line variability. These perturbations are most significant during contraction and are not in phase with the pulsation, transmitting information between consecutive pulsation cycles. This work shows RV curve modulation to be a consequence of atmospheric velocity gradient perturbations. Possible origins of these perturbations and their impact on Cepheid RV measurements as well as the projection factor used in Baade-Wesselink-type distance determinations are discussed.
- ID:
- ivo://CDS.VizieR/J/AJ/153/208
- Title:
- LCES HIRES/Keck radial velocity Exoplanet Survey
- Short Name:
- J/AJ/153/208
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe a 20 year survey carried out by the Lick-Carnegie Exoplanet Survey Team (LCES), using precision radial velocities from HIRES on the Keck I telescope to find and characterize extrasolar planetary systems orbiting nearby F, G, K, and M dwarf stars. We provide here 60949 precision radial velocities for 1624 stars contained in that survey. We tabulate a list of 357 significant periodic signals that are of constant period and phase, and not coincident in period and/or phase with stellar activity indices. These signals are thus strongly suggestive of barycentric reflex motion of the star induced by one or more candidate exoplanets in Keplerian motion about the host star. Of these signals, 225 have already been published as planet claims, 60 are classified as significant unpublished planet candidates that await photometric follow-up to rule out activity-related causes, and 54 are also unpublished, but are classified as "significant" signals that require confirmation by additional data before rising to classification as planet candidates. Of particular interest is our detection of a candidate planet with Msin(i)=3.8M_{Earth}_, and P=9.9 days orbiting Lalande 21185, the fourth-closest main-sequence star to the Sun. For each of our exoplanetary candidate signals, we provide the period and semi-amplitude of the Keplerian orbital fit, and a likelihood ratio estimate of its statistical significance. We also tabulate 18 Keplerian-like signals that we classify as likely arising from stellar activity.
- ID:
- ivo://CDS.VizieR/J/AJ/161/194
- Title:
- LCs and RVs of 5 exoplanets discovered by TESS
- Short Name:
- J/AJ/161/194
- Date:
- 11 Mar 2022
- Publisher:
- CDS
- Description:
- We present the discovery and characterization of five hot and warm Jupiters TOI-628b (TIC281408474; HD288842), TOI-640b (TIC147977348), TOI-1333b (TIC395171208, BD+473521A), TOI-1478b (TIC409794137), and TOI-1601b (TIC139375960)-based on data from NASA's Transiting Exoplanet Survey Satellite (TESS). The five planets were identified from the full-frame images and were confirmed through a series of photometric and spectroscopic follow-up observations by the TESS Follow-up Observing Program Working Group. The planets are all Jovian size (R_P_=1.01-1.77R_J_) and have masses that range from 0.85 to 6.33M_J_. The host stars of these systems have F and G spectral types (5595<~Teff<~6460K) and are all relatively bright (9.5<V<10.8, 8.2<K<9.3), making them well suited for future detailed characterization efforts. Three of the systems in our sample (TOI-640b, TOI-1333b, and TOI-1601b) orbit subgiant host stars (logg<4.1). TOI-640b is one of only three known hot Jupiters to have a highly inflated radius (R_P_>1.7R_J_, possibly a result of its host star's evolution) and resides on an orbit with a period longer than 5days. TOI-628b is the most massive, hot Jupiter discovered to date by TESS with a measured mass of 6.31_-0.30_^+0.28^M_J_ and a statistically significant, nonzero orbital eccentricity of e=0.074_-0.022_^+0.021^. This planet would not have had enough time to circularize through tidal forces from our analysis, suggesting that it might be remnant eccentricity from its migration. The longest-period planet in this sample, TOI-1478b (P=10.18days), is a warm Jupiter in a circular orbit around a near-solar analog. NASA's TESS mission is continuing to increase the sample of well-characterized hot and warm Jupiters, complementing its primary mission goals.
- ID:
- ivo://CDS.VizieR/J/A+A/642/A121
- Title:
- LHS1140 radial velocity data
- Short Name:
- J/A+A/642/A121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- LHS 1140 is an M dwarf known to host two transiting planets at orbital periods of 3.77 and 24.7 days. They were detected with HARPS and Spitzer. The external planet (LHS 1140 b) is a rocky super-Earth that is located in the middle of the habitable zone of this low-mass star. All these properties place this system at the forefront of the habitable exoplanet exploration, and it therefore constitutes a relevant case for further astrobiological studies, including atmospheric observations. We further characterize this system by improving the physical and orbital properties of the known planets, search for additional planetary-mass components in the system, and explore the possibility of co-orbitals. We collected 113 new high-precision radial velocity observations with ESPRESSO over a 1.5-yr time span with an average photon-noise precision of 1.07m/s. We performed an extensive analysis of the HARPS and ESPRESSO datasets and also analyzed them together with the new TESS photometry. We analyzed the Bayesian evidence of several models with different numbers of planets and orbital configurations. We significantly improve our knowledge of the properties of the known planets LHS 1140 b (Pb~24.7-days) and LHS 1140 c (Pc~3.77-days). We determine new masses with a precision of 6% for LHS 1140 b (6.48+/-0.46M_Earth_) and 9% for LHS 1140 c (m_c_=1.78+/-0.17M_Earth_). This reduces the uncertainties relative to previously published values by half. Although both planets have Earth-like bulk compositions, the internal structure analysis suggests that LHS 1140 b might be iron-enriched and LHS 1140 c might be a true Earth twin. In both cases, the water content is compatible to a maximum fraction of 10-12% in mass, which is equivalent to a deep ocean layer of 779+/-650 km for the habitable-zone planet LHS 1140 b. Our results also provide evidence for a new planet candidate in the system (m_d_=4.8+/-1.1M_Earth_) on a 78.9-day orbital period, which is detected through three independent methods. The analysis also allows us to discard other planets above 0.5M_Earth_ for periods shorter than 10 days and above 2 M_Earth_ for periods up to one year. Finally, our co-orbital analysis discards co-orbital planets in the tadpole and horseshoe configurations of LHS 1140 b down to 1M_Earth_ with a 95% confidence level (twice better than with the previous HARPS dataset). Indications for a possible co-orbital signal in LHS 1140 c are detected in both radial velocity (alternatively explained by a high eccentricity) and photometric data (alternatively explained by systematics), however. The new precise measurements of the planet properties of the two transiting planets in LHS 1140 as well as the detection of the planet candidate LHS 1140 d make this system a key target for atmospheric studies of rocky worlds at different stellar irradiations.
- ID:
- ivo://CDS.VizieR/J/A+A/409/251
- Title:
- Li abundances and velocities in F and G stars
- Short Name:
- J/A+A/409/251
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Lithium abundances have been determined in 127 F and G Pop I stars based on new measurements of the equivalent width of the {lambda}6707{AA} Li I line from their high resolution CCD spectra. Distances and absolute magnitudes of these stars have been obtained from the Hipparcos Catalogue (<I/239>) and their masses and ages derived, enabling us to investigate the behaviour of lithium as a function of these parameters. Based on their location on the HR diagram superposed on theoretical evolutionary tracks, the sample of the stars has been chosen to ensure that they have more or less completed their Li depletion on the main sequence.
- ID:
- ivo://CDS.VizieR/J/A+AS/133/221
- Title:
- Library of ELODIE spectra (F5-K7 stars)
- Short Name:
- J/A+AS/133/221
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A library of 211 echelle spectra taken with ELODIE at the Observatoire de Haute-Provence is proposed. It provides a set of spectroscopic standards covering the full range of gravities and metallicities in the effective temperature interval [4000K, 6300K]. The spectra are straightened, wavelength calibrated, cleaned of cosmic ray hits, bad pixels and telluric lines. They cover the spectral range [440nm, 680nm] with an instrumental resolution of 42000. For each star, basic data were compiled from the Hipparcos catalogue (Cat. <I/239>) and the Hipparcos Input Catalogue (Cat. <I/196>) (Table 1). Radial velocities with a precision better than 100m/s are given. Atmospheric parameters Teff, logg, [Fe/H] from the literature are discussed. Because of scattered determinations in the bibliography, even for the most well-known stars, these parameters were adjusted by an iterative process which takes account of common or different spectral features between the standards, using our homogeneous set of spectra. Revised values of effective temperature, gravity and metallicity are proposed in Table 1. They are still consistent with the literature, and also lead to the self-consistency of the library, in the sense that similar spectra have similar atmospheric parameters. This adjustment was performed by using step by step a method based on the least square comparison of carefully prepared spectra, which was originally developed for the on-line estimation of the atmospheric parameters of faint field stars (Katz et al., 1998A&A...338..151K. Paper I.).
- ID:
- ivo://CDS.VizieR/J/A+A/415/123
- Title:
- Lick line-index and photometry of globular clusters
- Short Name:
- J/A+A/415/123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog contains Lick line-index and photometric measurements of extragalactic globular clusters in seven early-type galaxies (NGC 1380, 2434, 3115, 3379, 3585, 5846, and 7192) with different morphological types (E/S0) located in field and group/cluster environments. High-quality spectra were taken with the FORS2 instrument at ESO's Very Large Telescope. ~50% of our data allows an age resolution {Delta}t/t~0.3 and a metallicity resolution ~0.25-0.4dex, depending on the absolute metallicity. Globular cluster candidates are selected from deep B, V, R, I, K FORS2/ISAAC photometry with 80-100% success rate inside one effective radius. Using combined optical/near-infrared colour-colour diagrams we present a method to efficiently reduce fore-/background contamination down to <~10%.
