- ID:
- ivo://CDS.VizieR/J/AZh/71/200
- Title:
- Spectral Investigation of NGC 7469
- Short Name:
- J/AZh/71/200
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This investigation is mainly related to hydrogen lines in the spectrum of NGC 7469 from the 1972-1990 data obtained using an image tube on the 2.6-m telescope of the Crimean Astrophysical Observatory. The decomposition of the hydrogen lines into broad and narrow components was performed. Variations in the intensities and broad-component contours were observed. One third of the spectrograms showed a broad, symmetric Ha line, while the others showed asymmetry: the blue wings fall more steeply than the red ones. The degree of asymmetry is variable, but no correlation between it and the brightness of the nucleus was found. This asymmetry becomes weaker when passing to higher members of the Balmer series. The halfwidths of the broad components increase from Ha to H{gamma}. Redshifts of broad components with respect to narrow ones might also be larger for higher members of the Balmer series. Intensities of the broad hydrogen lines follow continuum variations with a delay of about 28 days. The Balmer decrement for broad lines is much flatter than for narrow ones.
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- ID:
- ivo://CDS.VizieR/J/AJ/112/241
- Title:
- Spectral irradiance calibration. VI.
- Short Name:
- J/AJ/112/241
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present three new absolutely calibrated continuous stellar spectra from 3 to 35um, constructed as far as possible from actual observed spectral fragments taken from the Kuiper Airborne Observatory (KAO), and the IRAS Low Resolution Spectrometer (LRS). These stars - alpha1 Cen, alpha TrA, and epsilon Car - augment our previous archive of complete absolutely calibrated spectra for northern K and M giants. All these spectra have a common calibration pedigree. The wavelength coverage is ideal for calibration of many existing and proposed ground-based, airborne, and satellite sensors. KAO and IRAS data in the 15-30 um range suggest that the spectra of cool giants are close to Rayleigh-Jeans slopes. Our observations of alpha1 Cen, absolutely calibrated via our adopted Sirius model, indicate an angular diameter in very good agreement with values in the literature, demonstrating "closure" of the set of spectra within our absolute framework. We compare our observed alpha1 Cen spectrum with a published grid of theoretical models from Kurucz, and adopt a plausible theoretical shape, that fits our spectrum, as a secondary reference spectrum in the southern sky.
- ID:
- ivo://CDS.VizieR/J/AJ/112/2274
- Title:
- Spectral irradiance calibration. VII.
- Short Name:
- J/AJ/112/2274
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present five new absolutely calibrated continuous stellar spectra constructed as far as possible from spectral fragments observed from the ground, the Kuiper Airborne Observatory (KAO), and the IRAS Low Resolution Spectrometer. These stars, alpha Boo, gamma Dra, alpha Cet, gamma Cru, and mu UMa, augment our six, published, absolutely calibrated spectra of K and early-M giants. All spectra have a common calibration pedigree. A revised composite for alpha Boo has been constructed from higher quality spectral fragments than our previously published one. The spectrum of gamma Dra was created in direct response to the needs of instruments aboard the Infrared Space Observatory (ISO); this star's location near the north ecliptic pole renders it highly visible throughout the mission. We compare all our low-resolution composite spectra with Kurucz model atmospheres and find good agreement in shape, with the obvious exception of the SiO fundamental, still lacking in current grids of model atmospheres. The CO fundamental seems slightly too deep in these models, but this could reflect our use of generic models with solar metal abundances rather than models specific to the metallicities of the individual stars. Angular diameters derived from these spectra and models are in excellent agreement with the best observed diameters. The ratio of our adopted Sirius and Vega models is vindicated by spectral observations. We compare IRAS fluxes predicted from our cool stellar spectra with those observed and conclude that, as 12 and 25um, flux densities measured by IRAS should be revised downwards by about 4.1% to 5.7%, respectively, for consistency with our absolute calibration. We have provided extrapolated continuum versions of these spectra to 300um, in direct support of ISO (PHT and LWS instruments). These spectra are consistent with IRAS flux densities at 60 and 100um.
- ID:
- ivo://CDS.VizieR/J/other/AstBu/65.150
- Title:
- Spectral line identification in 3 Pup
- Short Name:
- J/other/AstBu/65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Optical spectra taken in 1997-2008 are used to analyze the spectral peculiarities and velocity field in the atmosphere of the peculiar supergiant 3 Pup.
- ID:
- ivo://CDS.VizieR/J/A+A/516/A42
- Title:
- Spectral lines of BK Peg and BW Aqr
- Short Name:
- J/A+A/516/A42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Double-lined, detached eclipsing binaries are our main source for accurate stellar masses and radii. In this paper we focus on the 1.15-1.70M_{sun}_ interval where convective core overshoot is gradually ramped up in theoretical evolutionary models. We aim to determine absolute dimensions and abundances for the F-type detached eclipsing binary BK Peg, and to perform a detailed comparison with results from recent stellar evolutionary models, including a sample of previously studied systems with accurate parameters.
- ID:
- ivo://CDS.VizieR/J/ApJS/193/17
- Title:
- Spectral-line survey of IRC+10216 at 293-355GHz
- Short Name:
- J/ApJS/193/17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a spectral-line survey of the extreme carbon star IRC+10216 carried out between 293.9 and 354.8GHz with the Submillimeter Array. A total of 442 lines were detected, more than 200 for the first time; 149 are unassigned. Maps at an angular resolution of ~3" were obtained for each line. A substantial new population of narrow lines with an expansion velocity of ~4km/s (i.e., ~30% of the terminal velocity) was detected. Most of these are attributed to rotational transitions within vibrationally excited states, emitted from energy levels above the {nu}=0, J=0 ground state with excitation energy of 1000-3000K. Emission from these lines appears to be centered on the star with an angular extent of <1". We use multiple transitions detected in several molecules to derive physical conditions in this inner envelope of IRC+10216.
- ID:
- ivo://CDS.VizieR/J/MNRAS/446/3842
- Title:
- Spectral line survey of two LOSs
- Short Name:
- J/MNRAS/446/3842
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of two Mopra 3-mm spectral line surveys of the lines of sight (LOS) towards the Galactic Centre (GC) molecular complexes Sgr B2 (LOS+0.693) and Sgr A (LOS-0.11). The spectra covered the frequency ranges of ~77-93 GHz and ~105-113 GHz. We have detected 38 molecular species and 25 isotopologues. The isotopic ratios derived from column density ratios are consistent with the canonical values, indicating that chemical isotopic fractionation and/or selective photodissociation can be considered negligible (<10 percent) for the GC physical conditions. The derived abundances and rotational temperatures are very similar for both LOSs, indicating very similar chemical and excitation conditions for the molecular gas in the GC. The excitation conditions are also very similar to those found for the nucleus of the starburst galaxy NGC 253. We report for the first time the detection of HCO and HOC^+^ emission in LOS+0.693. Our comparison of the abundance ratios between CS, HCO, HOC^+^ and HCO^+^ found in the two LOSs with those in typical Galactic photodissociation regions (PDRs) and starbursts galaxies does not show any clear trend to distinguish between ultraviolet- and X-ray-induced chemistries. We propose that the CS/HOC^+^ ratio could be used as a tracer of the PDR components in the molecular clouds in the nuclei of galaxies.
- ID:
- ivo://CDS.VizieR/J/A+A/596/A95
- Title:
- Spectral nuclear properties of NLS1 galaxies
- Short Name:
- J/A+A/596/A95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It is not yet well known whether narrow line Seyfert 1 (NLS1) galaxies follow the M_BH_-{sigma}_*_ relation found for normal galaxies. Emission lines, such as [SII] or [OIII]{lambda}5007, have been used as a surrogate of the stellar velocity dispersion and various results have been obtained. On the other hand, some active galactic nuclei (AGNs) have shown Balmer emission with an additional intermediate component (IC) besides the well-known narrow and broad lines. The properties of this IC have not yet been fully studied. In order to re-examine the location of NLS1 in the M_BH_-{sigma}_*_ relation, we test some emission lines, such as the narrow component (NC) of H{alpha} and the forbidden [NII]{lambda}{lambda}6548,6584 and [SII]{lambda}{lambda}6716,6731 lines, as replacements for {sigma}_*_. On the other hand, we study the properties of the IC of H{alpha} found in 14 galaxies of the sample to find a link between this component, the central engine, and the remaining lines. We also compare the emission among the broad component (BC) of H{alpha} and those emitted at the narrow line region (NLR) to detect differences in the ionizing source in each emitting region. We have obtained and studied medium-resolution spectra (170km/s FWHM at H{alpha}) of 36 NLS1 galaxies in the optical range ~5800-6800{AA}. We performed a Gaussian decomposition of the H{alpha}+[NII]{lambda}{lambda}6548,6584 profile to study the distinct components of H{alpha} and [NII] lines. We also measured the [SII] lines. We obtained black hole (BH) masses in the range log(M_{BH}_/M_{sun}_)=5.4-7.5 for our sample. We found that, in general, most of the galaxies lie below the M_BH_-{sigma}_*_ relation when the NC of H{alpha} and [NII] lines are used as a surrogate of {sigma}_*_. The objects are closer to the relation when [SII] lines are used. Nevertheless, the galaxies are still below this relation and we do not see a clear correlation between the BH masses and FWHM_[SII]_. Besides this, we found that 13 galaxies show an IC, most of which are in the velocity range ~700-1500km/s. This is same range as in AGN types and is well correlated with the FWHM of BC and, therefore, with the BH mass. On the other hand, we found that there is a correlation between the luminosity of the BC of H{alpha} and NC, IC, [NII]{lambda}6584, and [SII] lines.
- ID:
- ivo://CDS.VizieR/J/A+A/479/529
- Title:
- Spectral observations of symbiotic LL Cas
- Short Name:
- J/A+A/479/529
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- All tables contain the results of the spectral and photometric observations of the symbiotic star LL Cas. Observations were carried out within 1986-2006 with a slit spectrograph attached to the 0.7-m telescope of the Fessenkov Astrophysical Institute (Almaty, Kazakhstan). Some photoelectric observations of LL Cas with broad-band filters were carried out on a photoelectric polarimeter mounted on the 1-m Zeiss telescope (Assy-Turgen, Kazakhstan).
- ID:
- ivo://CDS.VizieR/J/A+A/530/A21
- Title:
- Spectral properties of 438 GRBs
- Short Name:
- J/A+A/530/A21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of the spectral analysis of the public data of 438 gamma ray bursts (GRBs) detected by the Fermi Gamma ray Burst Monitor (GBM) up to March 2010. For 432 bursts we could fit the time-integrated spectrum. In 318 cases we could reliably constrain the peak energy E^obs^_peak_ of their {nu}F{nu} spectrum by analyzing their time-integrated spectrum between 8keV and 35MeV. Eighty percent of these spectra are fitted by a power-law with an exponential cutoff, and the remaining with the Band function. Among these 318 GRBs, 274 belong to the long GRB class and 44 to the short.