- ID:
- ivo://CDS.VizieR/J/A+A/411/447
- Title:
- Interstellar NaI D-line
- Short Name:
- J/A+A/411/447
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present intermediate results from a long-term program of mapping the neutral absorption characteristics of the local interstellar medium, motivated by the availability of accurate and consistent parallaxes from the Hipparcos satellite. Equivalent widths of the interstellar NaI D-line doublet at 5890{AA} are presented for the lines-of-sight towards some 311 new target stars lying within ~350pc of the Sun. Using these data, together with NaI absorption measurements towards a further ~240 nearby targets published in the literature (for many of them, in the directions of molecular clouds), and the ~450 lines-of-sight already presented by (Sfeir et al., 1999, Cat. <J/A+A/346/785>), we show 3D absorption maps of the local distribution of neutral gas towards 1005 sight-lines with Hipparcos distances as viewed from a variety of different galactic projections. The data are synthesized by means of two complementary methods, (i) by mapping of iso-equivalent width contours, and (ii) by density distribution calculation from the inversion of column-densities, a method devised by Vergely et al. (2001A&A...366.1016V). Our present data confirms the view that the local cavity is deficient in cold and neutral interstellar gas. The closest dense and cold gas "wall", in the first quadrant, is at ~55-60pc. There are a few isolated clouds at closer distance, if the detected absorption is not produced by circumstellar material. The observations were obtained during 11 observing runs over the period 1998-2000.
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Search Results
- ID:
- ivo://CDS.VizieR/J/PAZh/26/465
- Title:
- IRAS 20004+2955 (V1027 Cyg) chemical comp.
- Short Name:
- J/PAZh/26/465
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on high-dispersion echelle spectra taken with the 6-m telescope, detailed chemical composition of the IR source IRAS 20004+2955 identified with the variable star V1027 Cyg is studied.
- ID:
- ivo://CDS.VizieR/J/ApJ/761/184
- Title:
- IR luminosities for dusty AGNs and QSOs
- Short Name:
- J/ApJ/761/184
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Mid-infrared spectroscopic measurements from the Infrared Spectrometer (IRS) on Spitzer are given for 125 hard X-ray active galactic nuclei (AGNs; 14-195keV) from the Swift Burst Alert Telescope (BAT) sample and for 32 AGNs with black hole masses (BHMs) from reverberation mapping. The 9.7{mu}m silicate feature in emission or absorption defines an infrared AGN classification describing whether AGNs are observed through dust clouds, indicating that 55% of the BAT AGNs are observed through dust. The 100 most luminous type 1 quasars as measured in {nu}L_{nu}_(7.8{mu}m) are found by comparing Sloan Digital Sky Survey (SDSS) optically discovered quasars with photometry at 22{mu}m from the Wide-Field Infrared Survey Explorer (WISE), scaled to rest frame 7.8{mu}m using an empirical template determined from IRS spectra. The most luminous SDSS/WISE quasars have the same maximum infrared luminosities for all 1.5<z<5, reaching total infrared luminosity L_IR_=10^14.4^L_{sun}_. Comparing with dust-obscured galaxies from Spitzer and WISE surveys, we find no evidence of hyperluminous obscured quasars whose maximum infrared luminosities exceed the maximum infrared luminosities of optically discovered quasars. Bolometric luminosities L_bol_ estimated from rest-frame optical or ultraviolet luminosities are compared to L_IR_. For the local AGN, the median logL_IR_/L_bol_=-0.35, consistent with a covering factor of 45% for the absorbing dust clouds. For the SDSS/WISE quasars, the median logL_IR_/L_bol_=0.1, with extremes indicating that ultraviolet-derived L_bol_ can be seriously underestimated even for type 1 quasars.
- ID:
- ivo://CDS.VizieR/J/ApJ/801/69
- Title:
- Iron EWs for 21 giant star members of NGC3201
- Short Name:
- J/ApJ/801/69
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- NGC 3201 is a globular cluster suspected to have an intrinsic spread in the iron content. We re-analyzed a sample of 21 cluster stars observed with UVES-FLAMES at the Very Large Telescope and for which Simmerer et al. (2013ApJ...764L...7S) found a 0.4dex wide [Fe/H] distribution with a metal-poor tail. We confirmed that when spectroscopic gravities are adopted, the derived [Fe/H] distribution spans ~0.4dex. On the other hand, when photometric gravities are used, the metallicity distribution from Fe I lines remains large, while that derived from Fe II lines is narrow and compatible with no iron spread. We demonstrate that the metal-poor component claimed by Simmerer et al. (2013ApJ...764L...7S) is composed by asymptotic giant branch stars that could be affected by non-local thermodynamical equilibrium effects driven by iron overionization. This leads to a decrease of the Fe I abundance, while leaving the Fe II abundance unaltered. A similar finding has been already found in asymptotic giant branch stars of the globular clusters M5 and 47 Tucanae. We conclude that NGC 3201 is a normal cluster, with no evidence of intrinsic iron spread.
- ID:
- ivo://CDS.VizieR/J/ApJS/214/23
- Title:
- IR spectra and photometry of z<0.5 quasars
- Short Name:
- J/ApJS/214/23
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As a step toward a comprehensive overview of the infrared (IR) diagnostics of the central engines and host galaxies of quasars at low redshift, we present Spitzer Space Telescope spectroscopic (5-40{mu}m) and photometric (24, 70, and 160{mu}m) measurements of all Palomar-Green (PG) quasars at z<0.5 and Two Micron All Sky Survey (2MASS) quasars at z<0.3. We supplement these data with Herschel measurements at 160{mu}m. The sample is composed of 87 optically selected PG quasars and 52 near-IR-selected 2MASS quasars. Here we present the data, measure the prominent spectral features, and separate emission due to star formation from that emitted by the dusty circumnuclear torus. We find that the mid-IR (5-30{mu}m) spectral shape for the torus is largely independent of quasar IR luminosity with scatter in the spectral energy distribution (SED) shape of <~0.2dex. Except for the silicate features, no large difference is observed between PG (unobscured --silicate emission) and 2MASS (obscured --silicate absorption) quasars. Only mild silicate features are observed in both cases. When in emission, the peak wavelength of the silicate feature tends to be longer than 9.7{mu}m, possibly indicating effects on grain properties near the active galactic nucleus. The IR color is shown to correlate with the equivalent width of the aromatic features, indicating that the slope of the quasar mid- to far-IR SED is to first order driven by the fraction of radiation from star formation in the IR bands.
- ID:
- ivo://CDS.VizieR/J/ApJ/730/19
- Title:
- IR spectra and SEDs for starbursts and AGNs
- Short Name:
- J/ApJ/730/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present spectroscopic results for all galaxies observed with the Spitzer Infrared Spectrograph (IRS) that also have total infrared fluxes f_IR_ measured with the Infrared Astronomical Satellite (IRAS), also using AKARI photometry when available. Infrared luminosities and spectral energy distributions (SEDs) from 8um to 160um are compared to polycyclic aromatic hydrocarbon emission from starburst galaxies or mid-infrared dust continuum from active galactic nuclei (AGNs) at rest-frame wavelengths ~8um. A total of 301 spectra are analyzed for which IRS and IRAS include the same unresolved source, as measured by the ratio f_{nu}_(IRAS 25um)/f_{nu}_(IRS 25um). Sources have 0.004<z<0.34 and 42.5<logL_IR_<46.8(erg/s) and cover the full range of starburst galaxy and AGN classifications.
- ID:
- ivo://CDS.VizieR/J/A+A/405/531
- Title:
- IR spectra of ISOGAL sources in Galactic Bulge
- Short Name:
- J/A+A/405/531
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work we present near-IR spectra (HK-band) of a sample of 107 sources with mid-IR excesses at 7 and 15{mu}m detected during the ISOGAL survey. Making use of the DENIS interstellar extinction map from Schultheis et al. (1999, Cat. <J/A+A/349/L69>) we derive luminosities and find that the Mbol vs. ^12^CO and Mbol vs. H_2_O diagrams are powerful tools for identifying supergiants, AGB stars, giants and young stellar objects. The majority of our sample are AGB stars (~80%) while we find four good supergiant candidates, nine young stellar objects and 12 RGB candidates. We have used the most recent K_0_-[15] relation by Jeong et al. (2002, in Mass-losing Pulsating tars and their Circumstellar Matter, ed. Y. Nakasa, M. Honma, & M. Sekiin) based on recent theoretical modeling of dust formation of AGB stars to determine mass-loss rates. The mass-loss rates of the supergiants are comparable with those in the solar neighbourhood while the long-period Variables cover a mass-loss range from -5<log(dM/dt)<-7. The red giant candidates lie at the lower end of the mass-loss rate range between -6.5<log(dM/dt)<-9. We used the equivalent width of the CO bandhead at 2.3 mum, the NaI doublet and the CaI triplet to estimate metallicities using the relation by Ramirez et al. (2000ApJ...537..205R). The metallicity distribution of the ISOGAL objects shows a mean [Fe/H]~-0.25dex with a dispersion of +/-0.40dex which is in agreement with the values of Ramirez et al. (2000ApJ...537..205R) for Galactic Bulge fields between b=-4{deg} and b=-1.3{deg}. A comparison with the solar neighbourhood sample of Lancon & Wood (2000, Cat. <J/A+AS/146/217>) shows that our sample is ~0.5dex more metal-rich on average.
- ID:
- ivo://CDS.VizieR/J/ApJS/226/11
- Title:
- IR spectroscopy of AGN & starbursts
- Short Name:
- J/ApJS/226/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A sample of 379 extragalactic sources is presented that has mid-infrared, high-resolution spectroscopy from the Spitzer Infrared Spectrograph (IRS) and also spectroscopy of the [CII]158{mu}m line from the Herschel Photodetector Array Camera and Spectrometer (PACS). The emission line profiles of [NeII]12.81{mu}m, [NeIII]15.55{mu}m, and [CII]158{mu}m are presented, and intrinsic line widths are determined (full width half maximum of Gaussian profiles after instrumental correction). All line profiles, together with overlays comparing the positions of PACS and IRS observations, are made available in the Cornell Atlas of Spitzer IRS Sources (CASSIS). Sources are classified from active galactic nucleus (AGN) to starburst based on equivalent widths of the 6.2{mu}m polycyclic aromatic hydrocarbon feature. It is found that intrinsic line widths do not change among classifications for [CII], with median widths of 207km/s for AGNs, 248km/s for composites, and 233km/s for starbursts. The [NeII] line widths also do not change with classification, but [NeIII] lines are progressively broader from starburst to AGN. A few objects with unusually broad lines or unusual redshift differences in any feature are identified.
- ID:
- ivo://CDS.VizieR/J/ApJ/683/114
- Title:
- IRS spectra of faint IRAS sources
- Short Name:
- J/ApJ/683/114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Extragalactic sources from the IRAS Faint Source Catalog (FSC) that have the optically faintest magnitudes (E>~18) were selected by spatial coincidence with a source in the FIRST radio survey, and 28 of these sources have been observed with the Infrared Spectrograph on Spitzer (IRS). While an infrared source is always detected with the IRS at the FIRST position, only ~50% of the infrared sources are real FSC detections, as estimated from the number of sources for which the f_v_(25um) determined with the IRS is fainter than the sensitivity limit for the FSC. Sources have 0.12<z<1.0 and luminosities 43.3<log[{nu}L_{nu}_(5.5um)]<46.7erg/s, encompassing the range from local ULIRGs to the most luminous sources discovered by Spitzer at z~2. Detectable PAH features are found in 15 of the sources (54%), and measurable silicate absorption is found in 19 sources (68%); both PAH emission and silicate absorption are present in 11 sources. PAH luminosities are used to determine the starburst fraction of bolometric luminosity, and model predictions for a dusty torus are used to determine the AGN fraction of luminosity in all sources based on vL_v_(5.5um). Approximately half of the sources have luminosity dominated by an AGN and approximately half by a starburst.
- ID:
- ivo://CDS.VizieR/J/AJ/151/146
- Title:
- IRS spectra with features of crystalline silicates
- Short Name:
- J/AJ/151/146
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The crystalline silicate features are mainly reflected in infrared bands. The Spitzer Infrared Spectrograph (IRS) collected numerous spectra of various objects and provided a big database to investigate crystalline silicates in a wide range of astronomical environments. We apply the manifold ranking algorithm to perform a systematic search for the spectra with crystalline silicate features in the Spitzer IRS Enhanced Products available. In total, 868 spectra of 790 sources are found to show the features of crystalline silicates. These objects are cross-matched with the SIMBAD database as well as with the Large Sky Area Multi-object Fiber Spectroscopic Telescope (LAMOST)/DR2 (Luo et al. 2016, Cat. V/149). The average spectrum of young stellar objects shows a variety of features dominated either by forsterite or enstatite or neither, while the average spectrum of evolved objects consistently present dominant features of forsterite in AGB, OH/IR, post-AGB, and planetary nebulae. They are identified optically as early-type stars, evolved stars, galaxies and so on. In addition, the strength of spectral features in typical silicate complexes is calculated. The results are available through CDS for the astronomical community to further study crystalline silicates.
