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1261. IR spectra of standard stars
ID:
ivo://CDS.VizieR/J/AJ/110/275
Title:
IR spectra of standard stars
Short Name:
J/AJ/110/275
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present five new absolutely calibrated continuous stellar spectra from 1.2 to 35 um, constructed as far as possible from actual observed spectral fragments taken from the ground, the Kuiper Airborne Observatory (KAO), and the IRAS Low Resolution Spectrometer (LRS). These stars -- Beta Peg, Alpha Boo, Beta And, Beta Gem, and Alpha Hya -- augment our already created complete absolutely calibrated spectrum for Alpha Tau. 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.
1262. IR spectroscopy in Orion A: transitional disks
ID:
ivo://CDS.VizieR/J/ApJ/769/149
Title:
IR spectroscopy in Orion A: transitional disks
Short Name:
J/ApJ/769/149
Date:
21 Oct 2021
Publisher:
CDS
Description:
Transitional disks are protoplanetary disks around young stars, with inner holes or gaps which are surrounded by optically thick outer, and often inner, disks. Here we present observations of 62 new transitional disks in the Orion A star-forming region. These were identified using the Spitzer Space Telescope's Infrared Spectrograph and followed up with determinations of stellar and accretion parameters using the Infrared Telescope Facility's SpeX. We combine these new observations with our previous results on transitional disks in Taurus, Chamaeleon I, Ophiuchus, and Perseus, and with archival X-ray observations. This produces a sample of 105 transitional disks of "cluster" age 3Myr or less, by far the largest hitherto assembled. We use this sample to search for trends between the radial structure in the disks and many other system properties, in order to place constraints on the possible origins of transitional disks. We see a clear progression of host-star accretion rate and the different disk morphologies. We confirm that transitional disks with complete central clearings have median accretion rates an order of magnitude smaller than radially continuous disks of the same population. Pre-transitional disks--those objects with gaps that separate inner and outer disks--have median accretion rates intermediate between the two. Our results from the search for statistically significant trends, especially related to dM/dt, strongly support that in both cases the gaps are far more likely to be due to the gravitational influence of Jovian planets or brown dwarfs orbiting within the gaps, than to any of the photoevaporative, turbulent, or grain-growth processes that can lead to disk dissipation. We also find that the fraction of Class II YSOs which are transitional disks is large, 0.1-0.2, especially in the youngest associations.
1263. IR spectroscopy of AGN & starbursts
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.
1264. IR spectroscopy of ices
ID:
ivo://CDS.VizieR/J/ApJS/86/713
Title:
IR spectroscopy of ices
Short Name:
J/ApJS/86/713
Date:
21 Oct 2021
Publisher:
CDS
Description:
Laboratory spectra through the mid-infrared (4000 to 500cm^-1^ [2.5-20 micron]) have been used to calculate the optical constants (n and k) and integrated absorption coefficients (A) for a variety of pure and mixed molecular ices of relevance to astrophysics. The ices studied were H2O, CH3OH, CO2, OCS, CH4, CO2+CH4, CO2+OCS, CO+CH4, CO+OCS, O2+CH4, O2+OCS, N2+CH4, N2+OCS, H2O+CH4, H2O+OCS, and H2O+CH3OH+CO+NH3. In addition, the measurements have been extended through the far-infrared (500 to 50cm^1^ [20-200 micron]) for the H2O, CH3OH, and H2O+CH3OH+NH3 ices.
1265. IR spectroscopy of symbiotic stars. XII. V934 Her
ID:
ivo://CDS.VizieR/J/ApJ/872/43
Title:
IR spectroscopy of symbiotic stars. XII. V934 Her
Short Name:
J/ApJ/872/43
Date:
21 Oct 2021
Publisher:
CDS
Description:
The X-ray symbiotic (SyXB) V934 Her = 4U1700+24 is an M giant-neutron star (NS) binary system. Employing optical and infrared radial velocities spanning 29yr combined with the extensive velocities in the literature, we compute the spectroscopic orbit of the M giant in that system. We determine an orbital period of 4391d, or 12.0yr, the longest for any SyXB and far longer than the 404 day orbit commonly cited for this system in the literature. In addition to the 12.0yr orbital period, we find a shorter period of 420 days, similar to the one previously found. Instead of orbital motion, we attribute this much shorter period to long secondary pulsation of the M3 III SRb variable. Our new orbit supports earlier work that concluded that the orbit is seen nearly pole-on, which is why X-ray pulsations associated with the NS have not been detected. We estimate an orbital inclination of 11.3{deg}+/-0.4{deg}. Arguments are made that this low inclination supports a pulsation origin for the 420 day secondary period. We also measure the CNO and Fe peak abundances of the M giant and find it to be slightly metal-poor compared to the Sun, with no trace of the NS-forming supernova event. The basic properties of the M giant and NS are derived. We discuss the possible evolutionary paths that this system has taken to get to its current state.
1266. IR spectrum of protonated ovalene (7-C_32_H_15_^+^)
ID:
ivo://CDS.VizieR/J/ApJ/825/96
Title:
IR spectrum of protonated ovalene (7-C_32_H_15_^+^)
Short Name:
J/ApJ/825/96
Date:
21 Oct 2021
Publisher:
CDS
Description:
The mid-infrared emission from galactic objects, including reflection nebulae, planetary nebulae, proto-planetary nebulae, molecular clouds, etc, as well as external galaxies, is dominated by the unidentified infrared (UIR) emission bands. Large protonated polycyclic aromatic hydrocarbons (H^+^PAHs) were proposed as possible carriers, but no spectrum of an H^+^PAH has been shown to exactly match the UIR bands. Here, we report the IR spectrum of protonated ovalene (7-C_32_H_15_^+^) measured in a para-hydrogen (p-H_2_) matrix at 3.2K, generated by bombarding a mixture of ovalene and p-H_2_ with electrons during matrix deposition. Spectral assignments were made based on the expected chemistry and on the spectra simulated with the wavenumbers and infrared intensities predicted with the B3PW91/6-311++G(2d,2p) method. The close resemblance of the observed spectral pattern to that of the UIR bands suggests that protonated ovalene may contribute to the UIR emission, particularly from objects that emit Class A spectra, such as the IRIS reflection nebula, NGC 7023.
1267. IR spectrum of Uranium hollow cathode lamps
ID:
ivo://CDS.VizieR/J/ApJS/195/24
Title:
IR spectrum of Uranium hollow cathode lamps
Short Name:
J/ApJS/195/24
Date:
21 Oct 2021
Publisher:
CDS
Description:
We provide new measurements of wavenumbers and line identifications of 10100 UI and UII near-infrared (NIR) emission lines between 2500cm^-1^ and 12000cm^-1^ (850-4000nm) using archival Fourier transform spectrometer spectra from the National Solar Observatory. This line list includes isolated uranium lines in the Y, J, H, K, and L bands (0.9-1.1um, 1.2-1.35um, 1.5-1.65um, 2.0-2.4um, and 3.0-4.0um, respectively), and provides six times as many calibration lines as thorium in the NIR spectral range. The line lists we provide enable inexpensive, commercially available uranium hollow cathode lamps to be used for high-precision wavelength calibration of existing and future high-resolution NIR spectrographs.
1268. IRS spectra at 38 positions in Galactic center
ID:
ivo://CDS.VizieR/J/ApJ/670/1115
Title:
IRS spectra at 38 positions in Galactic center
Short Name:
J/ApJ/670/1115
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present Spitzer IRS spectra (R~600, 10-38um) of 38 positions in the Galactic center, all at the same Galactic longitude and spanning +/-0.3{deg} in latitude. Our positions include the Arches Cluster, the Arched Filaments, regions near the Quintuplet Cluster, the "Bubble" lying along the same line of sight as the molecular cloud G0.11-0.11, and the diffuse interstellar gas along the line of sight at higher Galactic latitudes.
1269. IRS spectra of faint IRAS sources
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.
1270. IRS spectra of 22 O7-B5 I-V stars
ID:
ivo://CDS.VizieR/J/A+A/620/A32
Title:
IRS spectra of 22 O7-B5 I-V stars
Short Name:
J/A+A/620/A32
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present results of the analysis of a sample of 22 stars of spectral types from O7 to B5 and luminosity classes I-V for which spectra from the Infrared Spectrograph (IRS) of Spitzer are available. The IRS spectra of these stars are examined for signs of excess infrared (IR) emission by comparison with stellar atmospheric spectra. We find that the spectra of half of the studied stars are dominated by excess emission in the far-IR, including all six super- and bright giants. In order to examine the origin of the far-IR excess, we supplement the Spitzer data with optical high-resolution echelle spectroscopy ({lambda}{Delta}{lambda}~10^5^), near-IR high-contrast coronagraphic imaging taken with the SPHERE instrument at VLT with a spatial resolution of 0.05", and WISE and Herschel photometry. In the optical region, we detect various absorption and emission lines (H{alpha}, CIII, and NIII) irrespective of the far-IR excess. Pfund{alpha} and Humphrey{alpha} lines are observed at the same time as the far-IR excess. These lines are stronger in stars with far-IR excess than in stars without excess. A scattered-light disk in the central r<2.5" region of the far-IR excess stars HD149404, HD151804, and HD154368 can be excluded from H band imaging down to a 1{sigma} contrast of F(r)/F*~10^-6^. The far-IR excess is fit either by a free-free component from ionized gas as for the winds of hot stars or a large (1pc) circumstellar dust shell. The putative dust envelopes required to explain the excess have a visual extinction as low as a few hundred micro-mag.

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