- 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.
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Search Results
- 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.
- ID:
- ivo://CDS.VizieR/J/ApJ/832/108
- Title:
- Spectral properties of Type Ic & Ic-bl SNe
- Short Name:
- J/ApJ/832/108
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first systematic investigation of spectral properties of 17 Type Ic Supernovae (SNe Ic), 10 broad-lined SNe Ic (SNe Ic-bl) without observed gamma-ray bursts (GRBs), and 11 SNe Ic-bl with GRBs (SN-GRBs) as a function of time in order to probe their explosion conditions and progenitors. Using a number of novel methods, we analyze a total of 407 spectra, which were drawn from published spectra of individual SNe as well as from the densely time-sampled spectra of Modjaz+ (2014, J/AJ/147/99). In order to quantify the diversity of the SN spectra as a function of SN subtype, we construct average spectra of SNe Ic, SNe Ic-bl without GRBs, and SNe Ic-bl with GRBs. We find that SN 1994I is not a typical SN Ic, contrasting the general view, while the spectra of SN 1998bw/GRB 980425 are representative of mean spectra of SNe Ic-bl. We measure the ejecta absorption and width velocities using a new method described here and find that SNe Ic-bl with GRBs, on average, have quantifiably higher absorption velocities, as well as broader line widths than SNe without observed GRBs. In addition, we search for correlations between SN-GRB spectral properties and the energies of their accompanying GRBs. Finally, we show that the absence of clear He lines in optical spectra of SNe Ic-bl, and in particular of SN-GRBs, is not due to them being too smeared-out due to the high velocities present in the ejecta. This implies that the progenitor stars of SN-GRBs are probably free of the He-layer, in addition to being H-free, which puts strong constraints on the stellar evolutionary paths needed to produce such SN-GRB progenitors at the observed low metallicities.
- ID:
- ivo://CDS.VizieR/J/AZh/82/420
- Title:
- Spectral study of 19 radio sources
- Short Name:
- J/AZh/82/420
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical identifications, classifications, and radio spectra of 19 radio sources from a complete sample in flux-density with the declinations 10{deg}-12{deg}30' (J2000) obtained with the 6-m optical telescope (4000-9000{AA}) and RATAN-600 radio telescope (0.97-21.7GHz) of the Special Astrophysical Observatory. Twelve objects with redshifts from 0.573-2.694 have been classified as quasars, and two objects with featureless spectra as BL Lac objects. Four objects are emission-line radio galaxies with redshifts from 0.204 to 0.311, one object is an absorption-line radio galaxy with redshift 0.214. Radio flux densities have been obtained at six frequencies for all sources except for two extended objects. The radio spectra of five of the sources can be separated into extended and compact components. Three objects display substantial rapid and long-term variability of their flux densities.
- ID:
- ivo://CDS.VizieR/J/A+AS/131/295
- Title:
- Spectral survey of Case emission-line galaxies
- Short Name:
- J/A+AS/131/295
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of the follow-up spectroscopy of 178 emission-line galaxy (ELG) candidates from the Case objective-prism survey and nine Markarian galaxies with the 6m telescope are described. Only the candidates classified in the Case survey as those with emission lines were observed with the aim to form a statistical sample of blue compact galaxies (BCGs) with strong emission lines in the zone RA: 8h-16h, and DE: =+29deg-+38deg. We present the redshifts, equivalent widths and flux ratios for the strongest lines and the spectrum type for most of the galaxies with detected emission lines. A significant fraction (about 23%) of the observed Case galaxies do not show emission lines in blue. Preliminary analysis of the data is presented and the properties of the observed ELGs are compared with those of other known samples.
- ID:
- ivo://CDS.VizieR/J/ApJ/676/286
- Title:
- Spectral templates for galaxies from 0.2 to 10um
- Short Name:
- J/ApJ/676/286
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We built an optimal basis of low-resolution templates for galaxies over the wavelength range from 0.2 to 10um using a variant of the algorithm presented by Budavari and coworkers. We derived them using 11 bands of photometry from the NDWFS, FLAMEX, zBootes, and IRAC Shallow surveys for 16033 galaxies in the NDWFS Bootes field with spectroscopic redshifts measured by the AGN and Galaxy Evolution Survey. We also developed algorithms to accurately determine photometric redshifts, K-corrections, and bolometric luminosities using these templates. Our photometric redshifts have an accuracy of sigma_z_/(1+z)=0.04 when clipped to the best 95%. We used these templates to study the spectral type distribution in the field and to estimate luminosity functions of galaxies as a function of redshift and spectral type. In particular, we note that the 5-8um color distribution of galaxies is bimodal, much like the optical g-r colors.
