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1271. IRS spectra of solar-type stars
ID:
ivo://CDS.VizieR/J/ApJ/705/89
Title:
IRS spectra of solar-type stars
Short Name:
J/ApJ/705/89
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have observed 152 nearby solar-type stars with the Infrared Spectrometer (IRS) on the Spitzer Space Telescope. Including stars that met our criteria but were observed in other surveys, we get an overall success rate for finding excesses in the long-wavelength IRS band (30-34um) of 11.8%+/-2.4%. The success rate for excesses in the short-wavelength band (8.5-12um) is ~1% including sources from other surveys. Two stars (HD 40136 and HD 10647) show weak evidence for spectral features; the excess emission in the other systems is featureless. For most stars with excesses, we detect an excess at both IRS and Multiband Imaging Photometer for Spitzer (MIPS) wavelengths. Only three stars in this sample show a MIPS 70um excess with no IRS excess, implying that very cold dust is rare around solar-type stars.
1272. IRS spectra with features of crystalline silicates
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.
1273. IRTF J-band spectrum of Mrk 231
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.
1274. IRTF spectral indices for giant stars
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.
1275. IRX-{beta} relation of HII regions in NGC628
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.
1276. ISO Astrophysical Spectroscopic Database
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.
1277. ISOCAM CVF spectrometer 2.2-16.5{mu}m spectra
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.
1278. ISO deep asteroid search
ID:
ivo://CDS.VizieR/J/AJ/123/2070
Title:
ISO deep asteroid search
Short Name:
J/AJ/123/2070
Date:
21 Oct 2021
Publisher:
CDS
Description:
A total of six deep exposures (using the astronomical observation template CAM01 with a 6" pixel field of view) through the ISOCAM LW10 filter (IRAS band 1, i.e., 12{mu}m) were obtained on a ~15' square field centered on the ecliptic plane. Point sources were extracted using the technique described in 1999 by Deert et al. Twoknown asteroids appear in these frames, and 20 sources moving with velocities appropriate for main-belt asteroids are present. Most of the asteroids detected have flux densities less than 1 mJy, that is, between 150 and 350 times fainter than any of the asteroids observed by IRAS. These data provide the first direct measurement of the 12{mu}m sky-plane density for asteroids on the ecliptic equator. The median zodiacal foreground, as measured by ISOCAM during this survey, is found to be 22.1+/-1.5mJy/pixel, i.e. 26.2+/-1.7MJy/sr. The results presented here imply that the actual number of kilometer-sized asteroids may be higher than several recent estimates based upon observations at visual wavelengths and are in reasonable agreement with the statistical asteroid model. Using results from the observations presented here, together with three other recent population estimates, we conclude that the cumulative number of main-belt asteroids with diameters greater than 1km is (1.2+/-0.5)x10^6^.
1279. Isotopic H_2_CS laboratory spectroscopic study
ID:
ivo://CDS.VizieR/J/A+A/621/A143
Title:
Isotopic H_2_CS laboratory spectroscopic study
Short Name:
J/A+A/621/A143
Date:
21 Oct 2021
Publisher:
CDS
Description:
Thioformaldehyde is an abundant molecule in various regions of the interstellar medium. However, available laboratory data limit the accuracies of calculated transition frequencies in the submillimeter region, in particular for minor isotopic species. We aim to determine spectroscopic parameters of isotopologs of H_2_CS that are accurate enough for predictions well into the submillimeter region.
1280. Isotopic H_2_NCN laboratory spectroscopic study
ID:
ivo://CDS.VizieR/J/A+A/623/A93
Title:
Isotopic H_2_NCN laboratory spectroscopic study
Short Name:
J/A+A/623/A93
Date:
21 Oct 2021
Publisher:
CDS
Description:
Cyanamide is one of the few interstellar molecules containing two chemically different N atoms. It was detected recently toward the solar-type protostar IRAS 16293-2422 B together with H_2_N^13^CN and HDNCN in the course of the Atacama Large Millemeter/submillimeter Array (ALMA) Protostellar Interferometric Line Survey (PILS). The detection of the 15N isotopomers or the determination of upper limits to their column densities was hampered by the lack of accurate laboratory data at the frequencies of the survey. We wanted to determine spectroscopic parameters of the ^15^N isotopomers of cyanamide that are accurate enough for predictions well into the submillimeter region and to search for them in the PILS data.

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