- ID:
- ivo://CDS.VizieR/J/ApJ/788/123
- Title:
- IRTF J-band spectrum of Mrk 231
- Short Name:
- J/ApJ/788/123
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first J-band spectrum of Mrk 231, which reveals a large He I* {lambda}10830 broad absorption line with a profile similar to that of the well-known Na I broad absorption line. Combining this spectrum with optical and UV spectra from the literature, we show that the unusual reddening noted by Veilleux et al. (2013ApJ...764...15V) is explained by a reddening curve like those previously used to explain low values of total-to-selective extinction in Type Ia supernovae. The nuclear starburst may be the origin and location of the dust. Spatially resolved emission in the broad absorption line trough suggests nearly full coverage of the continuum emission region. The broad absorption lines reveal higher velocities in the He I* lines (produced in the quasar-photoionized H II region) compared with the Na I and Ca II lines (produced in the corresponding partially ionized zone). Cloudy simulations show that a density increase is required between the H II and partially ionized zones to produce ionic column densities consistent with the optical and IR absorption line measurements and limits, and that the absorber lies ~100 pc from the central engine. These results suggest that the He I* lines are produced in an ordinary quasar BAL wind that impacts upon, compresses, and accelerates the nuclear starburst's dusty effluent (feedback in action), and the Ca II and Na I lines are produced in this dusty accelerated gas. This unusual circumstance explains the rarity of Na I absorption lines; without the compression along our line of sight, Mrk 231 would appear as an ordinary iron low-ionization, broad absorption line quasar.
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- ID:
- ivo://CDS.VizieR/J/AJ/162/187
- Title:
- IRTF spectral indices for giant stars
- Short Name:
- J/AJ/162/187
- Date:
- 15 Mar 2022
- Publisher:
- CDS
- Description:
- We present infrared spectral indices (1.0-2.3{mu}m) of Galactic late-type giants and red supergiants (RSGs). We used existing and new spectra obtained at resolution power R=2000 with SpeX on the IRTF telescope. While a large CO equivalent width (EW), at 2.29{mu}m ([CO,2.29]>~45{AA}) is a typical signature of RSGs later than spectral type M0, [CO] of K-type RSGs and giants are similar. In the [CO,2.29] versus [MgI,1.71] diagram, RSGs of all spectral types can be distinguished from red giants because the MgI line weakens with increasing temperature and decreasing gravity. We find several lines that vary with luminosity, but not temperature: SiI (1.59{mu}m), Sr (1.033{mu}m), Fe+Cr+Si+CN (1.16{mu}m), Fe+Ti (1.185{mu}m), Fe+Ti (1.196{mu}m), Ti+Ca (1.28{mu}m), and Mn (1.29{mu}m). Good markers of CN enhancement are the Fe+Si+CN line at 1.087{mu}m and CN line at 1.093{mu}m. Using these lines, at the resolution of SpeX, it is possible to separate RSGs and giants. Contaminant O-rich Mira and S-type AGBs are recognized by strong molecular features due to water vapor features, TiO band heads, and/or ZrO absorption. Among the 42 candidate RSGs that we observed, all but one were found to be late types. Twenty-one have EWs consistent with those of RSGs, 16 with those of O-rich Mira AGBs, and one with an S-type AGB. These infrared results open new, unexplored, potential for searches at low resolution of RSGs in the highly obscured innermost regions of the Milky Way.
- ID:
- ivo://CDS.VizieR/J/ApJ/606/929
- Title:
- IR to mm observations of IRAS 18317-0757
- Short Name:
- J/ApJ/606/929
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present high-resolution, multiwavelength-continuum, and molecular-line images of the massive star forming region IRAS 18317-0757. The global infrared through millimeter spectral energy distribution can be approximated by a two-temperature model (25 and 63K) with a total luminosity of approximately log(L/L_{sun}_)=5.2. Previous submillimeter imaging resolved this region into a cluster of five dust cores, one of which is associated with the ultracompact HII region G23.955+0.150, and another with a water maser. In our new 2.7mm continuum image obtained with BIMA, only the UCHII region is detected, with total flux and morphology in good agreement with the free-free emission in the VLA centimeter-wave maps. For the other four objects, the nondetections at 2.7mm and in the MSX mid-infrared bands are consistent with cool dust emission with a temperature of 13-40K and a luminosity of 1000-40000L_{sun}_. By combining single-dish and interferometric data, we have identified over two dozen virialized C^18^O cores in this region that contain ~40% of the total molecular gas mass present.
- ID:
- ivo://CDS.VizieR/J/ApJ/826/209
- Title:
- IRX-{beta} relation of HII regions in NGC628
- Short Name:
- J/ApJ/826/209
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It has been found that the infrared-to-ultraviolet luminosity ratio (IRX) and ultraviolet spectral slope ({beta}) have a tight correlation in starburst galaxies, while in normal galaxies the relation is deviated and has a much larger scatter. Star formation regions are much simpler in both morphology and physical properties than galaxies, so their photometric and spectroscopic properties are more easily and accurately determined. We have used the integral field spectroscopy and multiband photometric images to study the IRX-{beta} relation of HII regions in a nearby galaxy, NGC 628. There are obvious correlations between the D_n_ (4000), stellar population age, star formation rate, especially H{alpha} equivalent width EW(H{alpha}), and deviation distance d_p_ from the starburst IRX-{beta} relation. However, there is little correlation between the Balmer decrement, metallicity, and d_p_. It is much more complicated than expected, so that we cannot introduce a single second parameter to describe the scatter and deviation of the HII region IRX-{beta} relation.
- ID:
- ivo://CDS.VizieR/III/242
- Title:
- ISO Astrophysical Spectroscopic Database
- Short Name:
- III/242
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This database will eventually contain all the published infrared lines observed by ISO, the Infrared Space Observatory. At this stage only a few percent of the total content is included but it is increasing steadily. Thus what is presented at this stage is a beta-version of the final product. ISO - the Infrared Space Observatory - was operational during about 28 months, between November 1995 and May 1998, until its cooling fluid (liquid helium) burnt out (Kessler et al. 1996A&A...315L..27K). It was the first far-infrared satellite equipped with two medium and high resolution spectrometers, SWS (Short Wavelength Spectrometer, 2.38-45.2{mu}m, de Graauw et al. 1996A&A...315L..49D) and LWS (Long Wavelength Spectrometer, 43-197{mu}m, Clegg et al. 1996A&A...315L..38C). Both spectrometers could be operated in grating or Fabry-Perot mode. In addition, the two other ISO instruments also provided spectroscopic data: ISOCAM (the ISO Camera, Cesarsky et al. 1996A&A...315L..32C) had a CVF (Circular Variable Filter) mode in 3 bands covering the range 2.3-17.3{mu}m, and ISOPHOT (The Imaging Photo-Polarimeter, Lemke et al. 1996A&A...315L..64L) had a dual grating spectrometer (PHOT-S) with resolving power of order 90 in two bands (2.5-4.9{mu}m and 5.8-11.6{mu}m). Detailed information about ISO and its four ISO instruments can be found in "The ISO Handbook" available on-line at http://www.iso.vilspa.esa.es/ The novelty, the richness and the unicity of the ISO spectroscopic data is what motivated us in compiling this data in a systematic and homogeneous way in order to make it available to the whole astronomical community. No other past, current or foreseen space project will overwrite this data, hence the importance of this compilation. In addition, queries on the database content will be a useful tool for the preparation of follow-up observations with other space, airborne or ground-based observatories such as Herschel, SOFIA, ALMA, VLT and more. In this early version, the database is very incomplete. It contains about 3000 lines which represents only a few percent of the total. Each observed and published ISO spectroscopic line corresponds to a physical line in IASD with up to 39 parameter/information fields. The description of the various columns is given below.
- ID:
- ivo://CDS.VizieR/J/ApJS/150/343
- Title:
- ISOCAM CVF spectrometer 2.2-16.5{mu}m spectra
- Short Name:
- J/ApJS/150/343
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present all ISOCAM Circular Variable Filter (CVF) spectra that cover more than one-third of the 2.2-16.5{mu}m spectral range of the instrument. The 364 spectra have been classified according to the classification system of Kraemer et al. (2002ApJS..140..389K), as modified by Hodge et al. (2004, Cat. <J/ApJS/151/299>) to account for the shorter wavelength range. Prior to classification, the spectra were processed and recalibrated to create a uniform database. Aperture photometry was performed at each wavelength centered on the brightest position in each image field and the various spectral segments merged into a single spectrum. The aperture was the same for all scale sizes of the images. Since this procedure differs fundamentally from that used in the initial ISOCAM calibration, a recalibration of the spectral response of the instrument was required for the aperture photometry. The recalibrated spectra and the software used to create them are available to the community on-line via the ISO Data Archive.
- ID:
- ivo://CDS.VizieR/J/A+A/401/613
- Title:
- ISOCAM-CVF spectroscopy of YSO environment
- Short Name:
- J/A+A/401/613
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a mid-infrared (5-16.5{mu}m) imaging spectroscopy survey of Young Stellar Objects (YSOs) and their surrounding environment in four low-mass star formation regions: R CrA, {rho} Ophiuchi, Serpens and Chamaeleon I. This survey was performed using ISOCAM and its Circular Variable Filters (CVF) and observed 42 YSO candidates: we were able to obtain complete 5-16.5{mu}m spectra for 40 of these with a spectral resolving power of {lambda}/{Delta}{lambda}~40.
- ID:
- ivo://CDS.VizieR/J/A+A/372/173
- Title:
- ISOCAM observations of the rho Ophiuchi cloud
- Short Name:
- J/A+A/372/173
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- File table1 contains the list of the 212 ISOCAM sources recognized as members of the rho Ophiuchi embedded cluster. It lists their J2000 coordinates, flux densities at 6.7 and 14.3 micron and associated rms uncertainties, as well as the corresponding near-infrared identifications and the adopted IR classes (Class I, II or III).
- ID:
- ivo://CDS.VizieR/J/A+A/458/789
- Title:
- ISOCAM survey of Serpens/G3-G6
- Short Name:
- J/A+A/458/789
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from an ISOCAM survey in the two broadband filters LW2 (5-8.5um) and LW3 (12-18um) of a 19'x16' field called Serp_NH3 centred on the optical group Serpens/G3-G6. A total of 186 sources were detected in the 6.7um band and/or the 14.3um band to a limiting sensitivity of ~2mJy. These have been cross-correlated with the 2MASS catalogue and are all listed in table1. Deep follow-up photometry in the Ks band obtained with Arnica at the Nordic Optical Telescope (NOT) is listed in table2. Deep L' band photometry of selected sources using SIRCA at the NOT is listed in table3. Continuum emission at 1.3mm and 3.6cm was observed with IRAM and VLA, respectively, and deep imaging in the 2.12um S(1) line of H2 was obtained with NOTCam at the NOT. We find strong evidence for a stellar population of 31 Class II sources (listed in table5), 5 flat-spectrum sources, 5 Class I sources (listed in table4), and two Class 0 sources. Our method does not sample the Class III sources.
- ID:
- ivo://CDS.VizieR/J/A+A/421/623
- Title:
- ISOCAM survey of YSOs in Serpens Cloud Core
- Short Name:
- J/A+A/421/623
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from an ISOCAM survey in the two broad band filters LW2 (5-8.5{mu}m) and LW3 (12-18{mu}m) of a 0.13 square degree coverage of the Serpens Main Cloud Core. A total of 392 sources were detected in the 6.7{mu}m band and 139 in the 14.3{mu}m band to a limiting sensitivity of ~2mJy. We identified 53 Young Stellar Objects (YSOs) with mid-IR excess from the single colour index [14.3/6.7], and 8 additional YSOs from the H-K/K-m_6.7_ diagram. Only 32 of these 61 sources were previously known to be YSO candidates.
