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- ID:
- ivo://CDS.VizieR/J/ApJ/784/126
- Title:
- Infrared photometry of all known members in Taurus
- Short Name:
- J/ApJ/784/126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have compiled photometry at 3.4, 4.6, 12, and 22{mu}m from the all-sky survey performed by the Wide-field Infrared Survey Explorer (WISE) for all known members of the Taurus complex of dark clouds. Using these data and photometry from the Spitzer Space Telescope, we have identified members with infrared excess emission from circumstellar disks and have estimated the evolutionary stages of the detected disks, which include 31 new full disks and 16 new candidate transitional, evolved, evolved transitional, and debris disks. We have also used the WISE All-Sky Source Catalog to search for new disk-bearing members of Taurus based on their red infrared colors. Through optical and near-infrared spectroscopy, we have confirmed 26 new members with spectral types of M1-M7. The census of disk-bearing stars in Taurus should now be largely complete for spectral types earlier than ~M8(M{>~}0.03M_{sun}_).
- ID:
- ivo://CDS.VizieR/J/other/NewA/11.557
- Title:
- Infrared photometry of BL Lac objects
- Short Name:
- J/other/NewA/11.
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- By using results from the 2MASS observation, the differences between the X-ray selected BL Lac objects (XBLs) and the radio selected ones (RBLs) in the near infrared are discussed in this paper. It is found that, statistically, the RBLs have redder near infrared colors and steeper spectral indices in the near infrared than XBLs, whereas the XBLs have more influences from their host galaxies than the RBLs. It is also seen that the RBLs have much brighter luminosity in the near infrared than the XBLs. In addition, the high polarization characteristics are found in common for RBLs, but not for XBLs.
- ID:
- ivo://CDS.VizieR/J/A+A/372/245
- Title:
- Infrared properties of barium stars
- Short Name:
- J/A+A/372/245
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a systematic survey for IRAS associations of barium stars. A total of 155 associations were detected, and IRAS low-resolution spectra exist for 50 barium stars. We use different color-color diagrams from the visual band to 60{mu}m, relations between these colors and the spectral type, the barium intensity, and the IRAS low-resolution spectra to discuss physical properties of barium stars in the infrared. It is confirmed that most barium stars have infrared excesses in the near infrared. However, a new result of this work is that most barium stars have no excesses in the far infrared. This fact may imply that infrared excesses of barium stars are mainly due to the re-emission of energy lost from the Bond-Neff depression. It is also shown that the spectral type and the barium intensity of barium stars are not correlated with infrared colors, but may be correlated with V-K color.
- ID:
- ivo://CDS.VizieR/J/A+A/505/L5
- Title:
- Infrared radial velocities of vB10
- Short Name:
- J/A+A/505/L5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present radial velocities of the M8V-type, very low-mass star vB 10 obtained at four different epochs between 2001 and 2008. We use high-resolution (R~20000) near-infrared (J-band) spectra taken with the NIRSPEC instrument on the Keck II telescope. Our data suggest that vB 10 shows radial velocity variability with an amplitude of ~1km/s, a result that is consistent with the recent finding of a massive planet companion around the star. More velocity measurements and a better sampling of the orbital phase are required to precisely constrain the orbital parameters and the individual masses of the pair.
- ID:
- ivo://CDS.VizieR/J/ApJ/629/288
- Title:
- Infrared sources near AFGL 5142
- Short Name:
- J/ApJ/629/288
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Near-infrared JHK' and H_2_ v=1-0 S(1) imaging observations of the star-forming region AFGL 5142 are presented. A cluster of young stars is confirmed to be embedded in the dense molecular cloud core. Many point sources are newly detected. The cluster's K'-magnitude distribution and [H-K'] color peak have brighter and redder magnitudes than those outside the cluster. Many of the cluster sources exhibit infrared excesses typical of T Tauri stars, Herbig Ae/Be stars, and protostars. The observations also reveal new H_2_ line emission around the cluster, exhibiting several jets, filaments, and a faint elliptical structure. The jets are associated with the CO outflows in the region. The powering sources of the jets, the CO outflows, and the small faint elliptical structure are identified and analyzed individually. The strong H_2_ jets and faint diffuse emission further confirm that the cluster is in an early stage of evolution.
- ID:
- ivo://CDS.VizieR/J/PASP/115/351
- Title:
- Infrared Southern Cool Carbon Stars
- Short Name:
- J/PASP/115/351
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A large set of deep, near-IR, objective-prism plates taken along the southern Galactic plane was searched for cool supergiants and carbon stars. Accurate coordinates and charts for 759 carbon stars in two Galactic longitude sectors within 7.5{deg} of the plane, 248{deg}<l<288{deg} and 320{deg}<l<341{deg}, are given, including 289 stars not previously published. Many of the new and known stars are found in the IRAS, DENIS, and 2MASS point-source catalogs. The 2MASS colors and the longitude distribution of cool carbon stars are discussed briefly.
- ID:
- ivo://CDS.VizieR/III/45
- Title:
- Infrared Spectra for 32 Stars
- Short Name:
- III/45
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Relative fluxes are presented for 46 spectra (30 stars plus the Sun), ranging in spectral type from A0 to M7. Spectra of seven carbon stars are included. Although some spectra cover the wavenumbers from 2500 to 8200, many spectra do not include wavenumbers less than 4000 and there are many gaps as a result of atmospheric absorption.
- ID:
- ivo://CDS.VizieR/J/ApJ/811/45
- Title:
- Infrared spectral properties of M giants
- Short Name:
- J/ApJ/811/45
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We observed a sample of 20 M giants with the Infrared Spectrograph on the Spitzer Space Telescope. Most show absorption structure at 6.6-6.8um which we identify as water vapor, and in some cases, the absorption extends from 6.4um into the SiO band at 7.5um. Variable stars show stronger H_2_O absorption. While the strength of the SiO fundamental at 8um increases monotonically from spectral class K0 to K5, the dependence on spectral class weakens in the M giants. As with previously studied samples, the M giants show considerable scatter in SiO band strength within a given spectral class. All of the stars in our sample also show OH band absorption, most noticeably in the 14-17um region. The OH bands behave much like the SiO bands, increasing in strength in the K giants but showing weaker dependence on spectral class in the M giants, and with considerable scatter. An examination of the photometric properties reveals that the V-K color may be a better indicator of molecular band strength than the spectral class. The transformation from Tycho colors to Johnson B-V color is double-valued, and neither B-V nor B_T_-V_T_ color increases monotonically with spectral class in the M giants like they do in the K giants.
- ID:
- ivo://CDS.VizieR/J/A+A/501/1059
- Title:
- Infrared spectra of 9 T dwarfs
- Short Name:
- J/A+A/501/1059
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Aims: We determine the effective temperature, surface gravity and projected rotational velocity of nine T dwarfs from the comparison of high-resolution near-infrared spectra and synthetic models, and estimate the mass and age of the objects from state-of-the-art models. Methods: We use the AMES-COND cloudless solar metallicity models provided by the PHOENIX code to match the spectra of nine T-type field dwarfs observed with the near-infrared high-resolution spectrograph NIRSPEC using ten echelle orders to cover part of the J band from 1.147 to 1.347{mu}m with a resolving power R~20000. The projected rotational velocity, effective temperature and surface gravity of the objects are determined based on the minimum root mean square of the differences between the modelled and observed relative fluxes. Estimates of the mass and age of the objects are obtained from effective temperature-surface gravity diagrams, where our results are compared with existing solar metallicity models. Results: The modelled spectra reproduce quite well the observed features for most of the T dwarfs, with effective temperatures in the range of 922-1009K, and surface gravities between 10^4.1^ and 10^4.9^cm/s^2^. Our results support the assumption of a dust free atmosphere for T dwarfs later than T5, where dust grains form and then gravitationally sediment into the low atmosphere. The modelled spectra do not accurately mimic some individual very strong lines like the KI doublet at 1.2436 and 1.2525{mu}m. Our modelled spectra does not match well the observed spectra of the two T dwarfs with earlier spectral types, namely SDSSp J125453.90-012247.4 (T2) and 2MASS J05591914-1404488 (T4.5), which is likely due to the presence of condensate clouds that are not incorporated in the models used here. By comparing our results and their uncertainties to evolutionary models, we estimate masses in the interval ~5-75M_J_ for T dwarfs later than T5, which are in good agreement with those found in the literature. We found apparent young ages that are typically between 0.1 and a few Gyr for the same T dwarfs, which is consistent with recent kinematical studies.
