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- ID:
- ivo://CDS.VizieR/J/A+A/420/683
- Title:
- Equivalent widths of 23 wide binaries
- Short Name:
- J/A+A/420/683
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present iron abundance analysis for 23 wide binaries with main sequence components in the temperature range 4900-6300K, taken from the sample of the pairs currently included in the radial velocity planet search on going at the Telescopio Nazionale Galileo (TNG) using the high resolution spectrograph SARG. The use of a line-by-line differential analysis technique between the components of each pair allows us to reach errors of about 0.02dex in the iron content difference. Most of the pairs have abundance differences lower than 0.02dex and there are no pairs with differences larger than 0.07dex. The four cases of differences larger than 0.02dex may be spurious because of the larger error bars affecting pairs with large temperature difference, cold stars and rotating stars.
- ID:
- ivo://CDS.VizieR/J/other/Sci/350.64
- Title:
- 51 Eri b near-infrared spectrum
- Short Name:
- J/other/Sci/350.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Directly detecting thermal emission from young extrasolar planets allows measurement of their atmospheric composition and luminosity, which is influenced by their formation mechanism. Using the Gemini Planet Imager, we discovered a planet orbiting the ~20Myr-old star 51 Eridani at a projected separation of 13 astronomical units. Near-infrared observations show a spectrum with strong methane and water vapor absorption. Modeling of the spectra and photometry yields a luminosity of L/LS=1.6-4.0x10^-6^ and an effective temperature of 600-750K. For this age and luminosity, "hot-start" formation models indicate a mass twice that of Jupiter. This planet also has a sufficiently low luminosity to be consistent with the "cold- start" core accretion process that may have formed Jupiter.
- ID:
- ivo://CDS.VizieR/J/A+A/603/A57
- Title:
- 51 Eri b SPHERE/IFS spectra & atmosphere models
- Short Name:
- J/A+A/603/A57
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- 51 Eridani b is an exoplanet around a young (20Myr) nearby (29.4pc) F0-type star, which was recently discovered by direct imaging. It is one of the closest direct imaging planets in angular and physical separation (~0.5", ~13AU) and is well suited for spectroscopic analysis using integral field spectrographs. We aim to refine the atmospheric properties of the known giant planet and to constrain the architecture of the system further by searching for additional companions. We used the extreme adaptive optics instrument SPHERE at the Very Large Telescope (VLT) to obtain simultaneous dual-band imaging with IRDIS and integral field spectra with IFS, extending the spectral coverage of the planet to the complete Y- to H-band range and providing additional photometry in the K12-bands (2.11, 2.25 micron). We present the first spectrophotometric measurements in the Y and K bands for the planet and revise its J-band flux to values 40% fainter than previous measurements. Cloudy models with uniform cloud coverage provide a good match to the data. We derive the temperature, radius, surface gravity, metallicity, and cloud sedimentation parameter fsed. We find that the atmosphere is highly super-solar ([Fe/H]~1.0), and the low fsed~1.26 value is indicative of a vertically extended, optically thick cloud cover with small sized particles. The model radius and surface gravity estimates suggest higher planetary masses of M_gravity_=9.1^+4.9^_-3.3_. The evolutionary model only provides a lower mass limit of >2M_jupiter_ (for pure hot-start). The cold-start model cannot explain the luminosity of the planet. The SPHERE and NACO/SAM detection limits probe the 51 Eri system at solar system scales and exclude brown-dwarf companions more massive than 20M_jupiter_ beyond separations of ~2.5AU and giant planets more massive than 2M_jupiter_ beyond 9 au.
- ID:
- ivo://CDS.VizieR/J/ApJS/224/3
- Title:
- ESSENCE 6yr spectroscopic follow-up
- Short Name:
- J/ApJS/224/3
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Equation of State: Supernovae trace Cosmic Expansion (ESSENCE) survey discovered 213 Type Ia supernovae at redshifts 0.1<z<0.81 between 2002 and 2008. We present their R- and I-band photometry, measured from images obtained using the MOSAIC II camera at the CTIO Blanco, along with rapid-response spectroscopy for each object. We use our spectroscopic follow-up observations to determine an accurate, quantitative classification, and precise redshift. Through an extensive calibration program we have improved the precision of the CTIO Blanco natural photometric system. We use several empirical metrics to measure our internal photometric consistency and our absolute calibration of the survey. We assess the effect of various potential sources of systematic bias on our measured fluxes, and estimate the dominant term in the systematic error budget from the photometric calibration on our absolute fluxes is ~1%.
- ID:
- ivo://CDS.VizieR/J/A+A/628/A104
- Title:
- [ESS2003] Q2343-BX610 reduced PdBI spectra
- Short Name:
- J/A+A/628/A104
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used the Plateau De Bure Interferometer to observe multiple CO and neutral carbon transitions in a z=2.2 main sequence disk galaxy, BX610. Our observation of CO(7-6), CO(4-3) and both far infrared [CI] lines complements previous observations of H-alpha and low-J CO, and reveal a galaxy that is vigorously forming stars with UV fields, (Log(G/G_0_)<3.25), less extreme than local ULIRGs or most starbursting submillimeter galaxies in the early universe. Our observations allow new independent estimates of the cold gas mass which indicate M_gas_~2x10^11^M_{sun}_, and suggest a modestly larger alpha_CO value of ~8.2. The corresponding gas depletion timescale is ~1.5Gyr. In addition to gas of modest density (Log(n[cm^-3^])<3) heated by star formation, BX610 shows evidence for a significant second gas component responsible for the strong high-J CO emission. This second component might either be a high density molecular gas component heated by star formation in a typical photodissociation region, or it could be molecular gas excited by low velocity C shocks. The CO(7-6) to far infrared luminosity ratio we observe is significantly higher than typical star forming galaxies and suggests that CO(7-6) is not a reliable star formation tracer in this galaxy.
- ID:
- ivo://CDS.VizieR/J/A+A/540/A133
- Title:
- {eta} Car emission spectrum (1700-10400{AA})
- Short Name:
- J/A+A/540/A133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present line identifications in the 1700 to 10400{AA} region for the Weigelt blobs B and D, located 0.1" to 0.3" NNW of {eta} Carinae. The aim of this work is to characterize the behavior of these luminous, dense gas blobs in response to the broad high-state and the short low-state of {eta} Carinae during its 5.54-year spectroscopic period.
- ID:
- ivo://CDS.VizieR/J/ApJ/499/517
- Title:
- Ethylene oxide spectrum
- Short Name:
- J/ApJ/499/517
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The cyclic molecule ethylene oxide (c-C_2_H_4_O) has recently been detected in the interstellar source Sgr B2N. Previous laboratory work on the rotational spectrum of this molecule extends only to a frequency of 123GHz. We report here the extension of the laboratory rotational spectrum of this species through the frequency range 262358GHz using a new fast scan spectrometer (fast scan submillimeter spectroscopic technique, FASSST). The newly measured lines have been combined with previous data at lower frequencies to form a data set consisting of 662 lines that has been assigned and fitted via a standard semirigid asymmetric top analysis. The spectral constants obtained from the fit have allowed us to predict the frequencies of many additional lines.
- ID:
- ivo://CDS.VizieR/J/ApJS/256/9
- Title:
- Euclid preparation. XIV. C3R2 survey DR3
- Short Name:
- J/ApJS/256/9
- Date:
- 18 Jan 2022 14:01:22
- Publisher:
- CDS
- Description:
- The Complete Calibration of the Color-Redshift Relation (C3R2) survey is obtaining spectroscopic redshifts in order to map the relation between galaxy color and redshift to a depth of i~24.5 (AB). The primary goal is to enable sufficiently accurate photometric redshifts for Stage IV dark energy projects, particularly Euclid and the Nancy Grace Roman Space Telescope (Roman), which are designed to constrain cosmological parameters through weak lensing. We present 676 new high-confidence spectroscopic redshifts obtained by the C3R2 survey in the 2017B-2019B semesters using the DEIMOS, LRIS, and MOSFIRE multiobject spectrographs on the Keck telescopes. Combined with the 4454 redshifts previously published by this project, the C3R2 survey has now obtained and published 5130 high-quality galaxy spectra and redshifts. If we restrict consideration to only the 0.2<z_p_<2.6 range of interest for the Euclid cosmological goals, then with the current data release, C3R2 has increased the spectroscopic redshift coverage of the Euclid color space from 51% (as reported by Masters+ 2017, J/ApJ/841/111) to the current 91%. Once completed and combined with extensive data collected by other spectroscopic surveys, C3R2 should provide the spectroscopic calibration set needed to enable photometric redshifts to meet the cosmology requirements for Euclid, and make significant headway toward solving the problem for Roman.
- ID:
- ivo://CDS.VizieR/J/A+A/644/A67
- Title:
- EUV estimates from CaII H&K activity
- Short Name:
- J/A+A/644/A67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Atmospheric escape is an important factor shaping the exoplanet population and hence drives our understanding of planet formation. Atmospheric escape from giant planets is driven primarily by the stellar X-ray and extreme- ultraviolet (EUV) radiation. Furthermore, EUV and longer wavelength UV radiation power disequilibrium chemistry in the middle and upper atmosphere. Our understanding of atmospheric escape and chemistry, therefore, depends on our knowledge of the stellar UV fluxes. While the far-ultraviolet fluxes can be observed for some stars, most of the EUV range is unobservable due to the lack of a space telescope with EUV capabilities and, for the more distant stars, to interstellar medium absorption. Thus, it becomes essential to have indirect means for inferring EUV fluxes from features observable at other wavelengths. We present here analytic functions for predicting the EUV emission of F, G, K, and M-type stars from the log R'HK activity parameter that is commonly obtained from ground-based optical observations of the Ca II H&K lines. The scaling relations are based on a collection of about 100 nearby stars with published log R'HK and EUV flux values, where the latter are either direct measurements or inferences from high-quality far-ultraviolet (FUV) spectra. The scaling relations presented here return EUV flux values with an accuracy of about three, which is slightly lower than that of other similar methods based on FUV or X-ray measurements.
