Search

Start Over Subject spectroscopy
701. Equivalent widths of QSOs
ID:
ivo://CDS.VizieR/J/ApJ/613/129
Title:
Equivalent widths of QSOs
Short Name:
J/ApJ/613/129
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of a search for variability in the equivalent widths (EWs) of narrow, associated (|{Delta}v|<=5000km/s) absorption lines found in the UV spectra of z<=1.5 quasars. The goal of this search was to use variability as a means of identifying absorption lines arising in gas that is intrinsic to the quasar central engine. We have compared archival Hubble Space Telescope (HST) Faint Object Spectrograph (FOS) spectra of quasars with recent spectra obtained as part of our own snapshot survey of the same objects with the Space Telescope Imaging Spectrograph (STIS). The intervals between observations are 4-10yr. We primarily focused on the C IV absorption lines, although we also studied other lines available in the same spectra (e.g., Ly{alpha}, N V, O VI).
702. Equivalent widths of 14 red giants
ID:
ivo://CDS.VizieR/J/PAZh/38/122
Title:
Equivalent widths of 14 red giants
Short Name:
J/PAZh/38/122
Date:
21 Oct 2021
Publisher:
CDS
Description:
The results of a comparative analysis of the elemental abundances in the atmospheres of 14 red giants with high Galactic space velocities are presented. For almost all of the chemical elements considered, the their abundance trends with metallicity correspond to those constructed for thick-disk dwarfs. In the case of sodium, the main factor affecting the [Na/Fe] abundance in the stellar atmosphere for red giants is the surface gravity that characterizes the degree of development of the convective envelope. The difference between the [Na/Fe] abundances in the atmospheres of thin- and thick-disk red giants has been confirmed.
703. Equivalent widths of two post-AGB stars
ID:
ivo://CDS.VizieR/J/A+A/417/269
Title:
Equivalent widths of two post-AGB stars
Short Name:
J/A+A/417/269
Date:
21 Oct 2021
Publisher:
CDS
Description:
In an effort to extend the still limited sample of s-process enriched post-AGB stars, high-resolution, high signal-to-noise VLT+UVES spectra of the optical counterparts of the infrared sources IRAS 06530-0213 and IRAS 08143-4406 were analysed.
704. Equivalent widths of 23 wide binaries
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.
705. 51 Eri b near-infrared spectrum
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.
706. 51 Eri b SPHERE/IFS spectra & atmosphere models
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.
707. ESSENCE 6yr spectroscopic follow-up
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%.
708. [ESS2003] Q2343-BX610 reduced PdBI spectra
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.
709. {eta} Car emission spectrum (1700-10400{AA})
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.
710. Ethylene oxide spectrum
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.

Limit your search

more »

more »

more »

more »

more »