- ID:
- ivo://CDS.VizieR/J/A+A/657/A68
- Title:
- HD 137496 system discovery
- Short Name:
- J/A+A/657/A68
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Most of the currently known planets are small worlds with radii between that of the Earth and Neptune. The characterization of planets in this regime shows a large diversity in compositions and system architectures, with distributions hinting at a multitude of formation and evolution scenarios. However, many planetary populations, such as high-density planets, are significantly under-sampled limiting our understanding on planet formation and evolution. NCORES is a large observing program conducted on the HARPS high-resolution spectrograph which aims to confirm the planetary status and to measure the masses of small transiting planetary candidates detected by transit photometry surveys in order to constrain their internal composition.Methods.Using photometry from the K2 satellite and radial velocities measured with the HARPS and CORALIE spectrographs, we search for planets around the bright (Vmag=10) and slightly evolved Sun-like star HD 137496. We precisely estimate the stellar parameters, M*=1.035+/-0.022M_{sun}_, R*= 1.587+/-0.028R_{sun}_, Teff=5799+/-61K,together with the chemical composition (e.g. [Fe/H]=-0.027+/-0.040dex) of the slightly evolved star. We detect two planets orbiting HD 137496. The inner planet, HD 137496 b, is a super-Mercury (an Earth-sized planet with the density of Mercury) with a mass of Mb=4.04+/-0.55M_{sun}_), a radius of Rb=1.31^+0.06^_-0.05_R_{sun}_ and a density of {rho}b=10.49^+2.08^_-1.82_g/cm^3^. From interior modeling analysis we find that the planet is composed mainly of iron, with the core representing over 70% of the planet's mass (Mcore/Mtotal=0.73^+0.11^_-0.12_). The outer planet, HD 137496 c, is an eccentric (e=0.477+/-0.004), long period (P=479.9^+1.0^_-1.1_days) giant planet (Mc*sinic=7.66+/-0.11M_{Jup}_) for which we do not detect a transit. HD 137496 b is one of the few super-Mercuries detected to date. The accurate characterization reported here enhances its role as a key target to better understand the formation and evolution of planetary systems. The detection of an eccentric long period giant companion also reinforces the link between the presence of small transiting inner planets and long period gas giants.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/503/601
- Title:
- HD 17156 transit photometry & radial velocities
- Short Name:
- J/A+A/503/601
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To improve the parameters of the HD17156 system (peculiar due to the eccentric and long orbital period of its transiting planet) and constrain the presence of stellar companions. Photometric data were acquired for 4 transits, and high precision radial velocity measurements were simultaneously acquired with SARG at TNG for one transit. The template spectra of HD 17156 was used to derive effective temperature, gravity, and metallicity. A fit of the photometric and spectroscopic data was performed to measure the stellar and planetary radii, and the spin-orbit alignment. Planet orbital elements and ephemeris were derived from the fit. Near infrared adaptive optic images was acquired with ADOPT at TNG. We have found that the star has a radius of R_S_=1.44+/-0.03R_{sun}_ and the planet R_P_=1.02+/-0.08R_{jup}_ The transit ephemeris is T_c_=2454756.73134+/-0.00020+N*21.21663+/-0.00045 BJD. The analysis of the Rossiter-Mclaughlin effect shows that the system is spin orbit aligned with an angle Beta=4.8+/-5.3deg The analysis of high resolution images has not revealed any stellar companion with projected separation between 150 and 1000 AU from HD17156. Here we present the photometric data of the transits of HD 17156b.
- ID:
- ivo://CDS.VizieR/J/A+A/426/247
- Title:
- HD 173977 uby photometry and HRV
- Short Name:
- J/A+A/426/247
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present spectroscopic and photometric observations of the star HD 173977. It appears that the star is part of a double line binary system, with a period of 1.801d, corresponding to twice the period of the photometric variations. Hence the star is an ellipsoidal variable. The system is probably synchronized. The physical parameters of both components were derived through two independent methods, one based on evolutionary tracks, the other being the result of the behaviour of light curves in a close binary system. After removing the ellipsoidal variations, 3 frequencies are detected in the photometric data: 8.56, 14.51 and 16.42d^-1^, while 2 additional frequencies are also possible: 10.96 and 12.11d^-1^. In accordance with its position in the HR diagram, the primary component of HD 173977 should be considered as a delta Scuti star and no longer as a gamma Doradus star. In addition, HD 173844, used as a check star, is discovered variable with a 15.79d^-1^ frequency and is classified as a delta Scuti star.
- ID:
- ivo://CDS.VizieR/J/ApJ/832/131
- Title:
- HD 88133 11-yrs radial velocity measurements
- Short Name:
- J/ApJ/832/131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We target the thermal emission spectrum of the non-transiting gas giant HD 88133 b with high-resolution near-infrared spectroscopy, by treating the planet and its host star as a spectroscopic binary. For sufficiently deep summed flux observations of the star and planet across multiple epochs, it is possible to resolve the signal of the hot gas giant's atmosphere compared to the brighter stellar spectrum, at a level consistent with the aggregate shot noise of the full data set. To do this, we first perform a principal component analysis to remove the contribution of the Earth's atmosphere to the observed spectra. Then, we use a cross-correlation analysis to tease out the spectra of the host star and HD 88133 b to determine its orbit and identify key sources of atmospheric opacity. In total, six epochs of Keck NIRSPEC L-band observations and three epochs of Keck NIRSPEC K-band observations of the HD 88133 system were obtained. Based on an analysis of the maximum likelihood curves calculated from the multi-epoch cross-correlation of the full data set with two atmospheric models, we report the direct detection of the emission spectrum of the non-transiting exoplanet HD 88133 b and measure a radial projection of the Keplerian orbital velocity of 40+/-15km/s, a true mass of 1.02_-0.28_^+0.61^M_J_, a nearly face-on orbital inclination of 15_-5_^+6^{deg}, and an atmosphere opacity structure at high dispersion dominated by water vapor. This, combined with 11 years of radial velocity measurements of the system, provides the most up-to-date ephemeris for HD 88133.
- ID:
- ivo://CDS.VizieR/J/ApJ/892/L35
- Title:
- He+He white dwarf SDSSJ232230.20+050942.0 RVels
- Short Name:
- J/ApJ/892/L35
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of a 1201s orbital period binary, the third shortest-period detached binary known. Sloan Digital Sky Survey J232230.20+050942.06 contains two He-core white dwarfs orbiting with a 27{deg} inclination. Located 0.76kpc from the Sun, the binary has an estimated Laser Interferometer Space Antenna (LISA) 4yr signal-to-noise ratio of 40. J2322+0509 is the first He+He white dwarf LISA verification binary, a source class that is predicted to account for one-third of resolved LISA ultra-compact binary detections.
- ID:
- ivo://CDS.VizieR/J/A+A/441/685
- Title:
- HeI & HeII radial velocities of Sk 160/SMC X-1
- Short Name:
- J/A+A/441/685
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new optical spectroscopy of the eclipsing binary pulsar Sk 160/SMC X-1. From the He I absorption lines, taking heating corrections into account, we determine the radial velocity semi-amplitude of Sk 160 to be 21/8+/-1.8km/s. Assuming Sk 160 fills its Roche-lobe, the inclination angle of the system is i=65.3+/-1.3{deg} and in this case we obtain upper limits for the mass of the neutron star as Mx=1.21+/-0.10M_{sun}_ and for Sk 160 as Mo=16.6+/-0.4M_{sun}.
- ID:
- ivo://CDS.VizieR/J/A+A/407/31
- Title:
- Heliocentric radial velocities in Abell 376
- Short Name:
- J/A+A/407/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a dynamical analysis of the galaxy cluster Abell 376 based on a set of 73 velocities, most of them measured at Pic du Midi and Haute-Provence observatories and completed with data from the literature. Data on individual galaxies are presented and the accuracy of the determined velocities is discussed as well as some properties of the cluster. We obtained an improved mean redshift value z=0.0478^+0.005_-0.006_ and velocity dispersion {sigma}=852^+120^_-76_km/s. Our analysis indicates that inside a radius of ~900h_70_^-1^kpc (~15-arcmin) the cluster is well relaxed without any remarkable feature and the X-ray emission traces fairly well the galaxy distribution. A possible substructure is seen at 20-arcmin from the centre towards the Southwest direction, but is not confirmed by the velocity field. This SW clump is, however, kinematically bound to the main structure of Abell 376. A dense condensation of galaxies is detected at 46 arcmin (projected distance 2.6h_70_^-1^Mpc) from the centre towards the Northwest and analysis of the apparent luminosity distribution of its galaxies suggests that this clump is part of the large scale structure of Abell 376. X-ray spectroscopic analysis of ASCA data resulted in a temperature kT=4.3+/-0.4keV and metal abundance Z=0.32+/-0.08Z_{sun}. The velocity dispersion corresponding to this temperature using the T_X_-{sigma} scaling relation is in agreement with the measured galaxies velocities.
- ID:
- ivo://CDS.VizieR/J/MNRAS/482/4174
- Title:
- Heliocentric radial velocities of R CrB
- Short Name:
- J/MNRAS/482/4174
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Radial-velocity observations made on more than a thousand nights are presented for the type star of the R Coronae Borealis (RCB) class. There are four principal sources: the Lick Observatory (1950 to 1953), the original Cambridge radial-velocity spectrometer (1968 to 1991), and the Haute-Provence and Cambridge Coravels (1986 to 1998 and 1997 to 2007, respectively). In the case of the last set the size (equivalent width) and width (expressed as if Vsin(i)) of the Coravel cross-correlation (dip) profiles are also given, and the variation and complexity of those profiles are discussed. Although there is often evidence of cyclical behaviour in radial velocity, no coherent periodicity is found in any of the series. From time to time, and especially over 100 days before the great decline of 2007, the atmosphere was highly disturbed, with evidence of high-velocity components. We suggest that those are associated with large turbulent elements and result in mass ejection to sufficient distances for the formation of soot and other solids and thus the initiation of RCB-type declines. We associate the changes in light and radial velocity near maximum light primarily with the combined effect of such turbulent elements, and not with coherent pulsation. There is some evidence for a variation in the mean radial velocity on a time scale of about ten thousand days.
- ID:
- ivo://CDS.VizieR/J/AJ/115/6
- Title:
- Hercules supercluster kinematics
- Short Name:
- J/AJ/115/6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Hercules supercluster consists of the Abell clusters A2147, A2151, and A2152. Previous studies of the kinematics have been confounded by the difficulty of correctly assigning galaxies to the individual clusters, which are not well separated. Our study has a total of 468 available velocities for galaxies in the region, 175 of them new. There are 414 galaxies in the supercluster, about 3 times the number used in the previous supercluster study. We verify the existence of the three individual clusters and compute their individual dynamical parameters. We investigate several techniques for assigning galaxy membership to clusters in this crowded field. We use the Kaye's mixture model (Ashman, Bird, & Zepf, 1994AJ....108.2348A) algorithm to separate the galaxies into clusters; we find that A2152 has a higher mean velocity than previous studies have reported. A2147 and A2152 also have lower velocity dispersions: 821^+68^_-55_ and 715^+81^_-61_km/s, respectively. The assignment of galaxies to either A2152 or A2147 requires velocity and position information. We study the kinematics of the supercluster using the two-body formalism of Beers, Geller, & Huchra (1982ApJ...257...23B) and conclude that A2147 and A2151 are probably bound to each other and that the supercluster as a whole may also be bound. The mass of the supercluster, if bound, is (7.6+/-2.0)x10^15^h^-1^M_{sun}_; with the supercluster luminosity, (1.4+/-0.2)x10^13^h^-2^L_{sun}_, this yields {OMEGA}=0.34+/-0.1.
- ID:
- ivo://CDS.VizieR/J/PASP/122/261
- Title:
- Herschel Reference Survey Sample
- Short Name:
- J/PASP/122/261
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Herschel Reference Survey is a Herschel guaranteed time key project and will be a benchmark study of dust in the nearby universe. The survey will complement a number of other Herschel key projects including large cosmological surveys that trace dust in the distant universe. We will use Herschel to produce images of a statistically-complete sample of 323 galaxies at 250, 350, and 500um. The sample is volume-limited, containing sources with distances between 15 and 25Mpc and flux limits in the K band to minimize the selection effects associated with dust and with young high-mass stars and to introduce a selection in stellar mass. The sample spans the whole range of morphological types (ellipticals to late-type spirals) and environments (from the field to the center of the Virgo Cluster) and as such will be useful for other purposes than our own. We plan to use the survey to investigate (i) the dust content of galaxies as a function of Hubble type, stellar mass, and environment; (ii) the connection between the dust content and composition and the other phases of the interstellar medium; and (iii) the origin and evolution of dust in galaxies. In this article, we describe the goals of the survey, the details of the sample and some of the auxiliary observing programs that we have started to collect complementary data. We also use the available multifrequency data to carry out an analysis of the statistical properties of the sample.
