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- ID:
- ivo://CDS.VizieR/J/AJ/105/1860
- Title:
- 2-35 micron point source IR sky model
- Short Name:
- J/AJ/105/1860
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Point Source Infrared Sky Model of Wainscoat et al. [ApJS, 83, 111 (1992)] is extended to make predictions for any filter lying wholly within the range 2.0 to 35.0 microns. The development of a library of complete 2-35micron low-resolution spectra (with 0.1micron step size) that represent the 87 categories of Galactic object and four types of extragalactic source implicit in the Model supports this extension. This library is based upon the "spectral template" technique whereby existing spectral fragments for individual sources (from ground-based, airborne, and satellite-borne instruments) are combined into complete spectra. Templates provide a natural way to represent the complete spectral energy distributions of celestial sources for which only infrared photometry and/or partial spectroscopy are available. Consequently, templates bear upon the important general problem of establishing midinfrared calibration sources. The new Model is validated by comparison with broadband K (2.2micron) source counts.
- ID:
- ivo://CDS.VizieR/J/ApJS/142/79
- Title:
- 1-1.4 micron spectral atlas of stars
- Short Name:
- J/ApJS/142/79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of J-band (1.08 to 1.35{mu}m) stellar spectra at low resolution (R~400). The targets consist of 105 stars ranging in spectral type from O9.5 to M7 and luminosity classes I through V. The relatively featureless spectra of hot stars, earlier than A4, can be used to remove the atmospheric features which dominate ground-based J-band spectroscopy. We measure equivalent widths for three absorption lines and nine blended features which we identify in the spectra. Using detailed comparison with higher resolution spectra, we demonstrate that low-resolution data can be used for stellar classification, since several features depend on the effective temperature and gravity. For example, the CN index (1.096-1.104{mu}m) decreases with temperature, but the strength of a blended feature at 1.28{mu}m (consisting of primarily P{beta}) increases. The slope of a star's spectrum can also be used to estimate its effective temperature. The luminosity class of a star correlates with the ratio of the MgI (1.1831{mu}m) line to a blend of several species at 1.16{mu}m. Using these indicators, a star can be classified to within several subclasses. Fifteen stars with particularly high and low metal abundances are included in the catalog, and some spectral dependence on metal abundance is also found.
- ID:
- ivo://CDS.VizieR/II/56
- Title:
- 100-Micron Survey of the Galactic Plane
- Short Name:
- II/56
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog represents a survey of a portion of the galactic plane at a wavelength of 100 micrometers with a balloon-borne, stabilized, 12-inch infrared telescope having a sensitivity of 10(-22) W/m2/Hz. The survey covers 750 square degrees of the sky, including most of the galactic plane between galactic longitudes of 335 and 88 degrees, plus a number of other selected areas of interest. Seventy-two sources have been detected, 60 of which are identified with continuum radio sources, bright nebulae, dark nebulae, and infrared stars. The catalog includes right ascension and declination (B1950.0), galactic coordinates, 100-micrometer peak flux densities, sizes of sources, and identifications.
11045. Microquasar candidates
- ID:
- ivo://CDS.VizieR/J/A+A/477/125
- Title:
- Microquasar candidates
- Short Name:
- J/A+A/477/125
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Microquasars are ideal natural laboratories for understanding accretion/ejection processes, studying the physics of relativistic jets, and testing gravitational phenomena. Nevertheless, these objects are difficult to find in our Galaxy. The main goal of this work is to increase the number of known systems of this kind, which should allow better testing of high-energy phenomena and more realistic statistical studies of this galactic population to be made. We have developed an improved search strategy based on positional cross-identification with very restrictive selection criteria to find new MQs, taking advantage of more sensitive modern X-ray data. To do this, we made combined use of the radio, infrared, and X-ray properties of the sources, using different available catalogs.
- ID:
- ivo://CDS.VizieR/J/A+A/564/A82
- Title:
- Microwave spectra of CH3CHCCHCN
- Short Name:
- J/A+A/564/A82
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A successful identification of an interstellar compound requires that its spectrum has first been assigned in the laboratory. New and sensitive radiotelescopes, such as ALMA, will make it possible to detect interstellar molecules in much smaller concentrations than before. Cyanoallene (CH_2_=C=CH-CN) has recently been observed in the dense molecular cloud TMC-1 by means of its rotational spectrum. Its methyl congener, 4-methylcyanoallene (CH_3_CH=C=CH-CN), may also be present in the interstellar medium (ISM). This chiral compound exists in two forms, which are mirror images. Chirality is an essential feature of life. So far, no chiral compounds have been detected in the ISM. The synthesis and assignment of the rotational spectrum of CH_3_CH=C=CH-CN, will facilitate the potential detection of this compound in the ISM.
- ID:
- ivo://CDS.VizieR/J/A+A/558/A6
- Title:
- Microwave spectrum of 2-pentynenitrile (C2H5CCCN)
- Short Name:
- J/A+A/558/A6
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New radiotelescopes, such as the very sensitive ALMA, will enable the detection of interstellar molecules in much lower concentrations than previously possible. A successful identification of an interstellar molecule requires that laboratory microwave and millimeter-wave spectra are investigated. Several cyanopolyynes and alkynylcarbonitriles have already been detected in the interstellar medium (ISM). Cyanoacetylene (HCCCN) is abundant in the ISM and its methyl derivative, 2-butynenitrile (CH3CCCN), is also present. The next derivative, ethyl cyanoacetylene, (2-pentynenitrile C_2_H_5_CCCN) may also be present in interstellar space. We report the rotational spectrum of the ethyl cyanoacetylene (C_2_H_5_CCCN). This is hoped to facilitate identifying gaseous ethyl cyanoacetylene in the ISM.
11048. Mid-eclipse times of DV UMa
- ID:
- ivo://CDS.VizieR/J/AJ/153/238
- Title:
- Mid-eclipse times of DV UMa
- Short Name:
- J/AJ/153/238
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- DV UMa is an eclipsing dwarf nova with an orbital period of ~2.06hr, which lies just at the bottom edge of the period gap. To detect its orbital period changes, we present 12 new mid-eclipse times by using our CCD photometric data and archival data. The latest version of the O-C diagram, combined with the published mid-eclipse times in quiescence, and spanning ~30 years, was obtained and analyzed. The best fit to those available eclipse timings shows that the orbital period of DV UMa is undergoing a cyclic oscillation with a period of 17.58(+/-0.52) years and an amplitude of 71.1(+/-6.7) s. The periodic variation most likely arises from the light-travel-time effect via the presence of a circumbinary object, because the required energy to drive the Applegate mechanism is too high in this system. The mass of the unseen companion was derived as M_3_sini'=0.025(+/-0.004)M_{Sun}_. If the third body is in the orbital plane (i.e., i'=i=82.9{deg}) of the eclipsing pair, this would indicate it is a brown dwarf. This hypothetical brown dwarf is orbiting its host star at a separation of ~8.6 au in an eccentric orbit (e=0.44).
- ID:
- ivo://CDS.VizieR/J/AJ/157/150
- Title:
- Mid-eclipse times of KIC 10544976
- Short Name:
- J/AJ/157/150
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In recent years, several close post-common-envelope eclipsing binaries have been found to show cyclic eclipse timing variations (ETVs). This effect is usually interpreted either as the gravitational interaction among circumbinary bodies and the host binary - known as the light travel time (LTT) effect - or as the quadrupole moment variations in one magnetic active component - known as the Applegate mechanism. In this study, we present an analysis of the ETV and the magnetic cycle of the close binary KIC 10544976. This system is composed of a white dwarf and a red dwarf in a short orbital period (0.35 days) and was monitored by ground-based telescopes between 2005 and 2017 and by the Kepler satellite between 2009 and 2013. Using the Kepler data, we derived the magnetic cycle of the red dwarf by two ways: the rate and energy of flares and the variability due to spots. Both methods resulted in a cycle of ~600 days, which is in agreement with magnetic cycles measured for single low-mass stars. The orbital period of KIC 10544976 shows only one long-term variation which can be fitted by an LTT effect with period of ~16.8 yr. Hence, one possible explanation for the ETVs is the presence of a circumbinary body with a minimal mass of ~13.4 M_Jup_. In the particular scenario of coplanarity between the external body and the inner binary, the third body mass is also ~13.4 M_Jup_. In this case, the circumbinary planet must either have survived the evolution of the host binary or have been formed as a consequence of its evolution.
- ID:
- ivo://CDS.VizieR/J/A+A/617/A83
- Title:
- MIDI atlas of low- and intermediate-mass YSOs
- Short Name:
- J/A+A/617/A83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Protoplanetary disks show large diversity regarding their morphology and dust composition. With mid-infrared interferometry the thermal emission of disks can be spatially resolved, and the distribution and properties of the dust within can be studied. Our aim is to perform a statistical analysis on a large sample of 82 disks around low- and intermediate-mass young stars, based on mid-infrared interferometric observations. We intend to study the distribution of disk sizes, variability, and the silicate dust mineralogy. Archival mid-infrared interferometric data from the MIDI instrument on the Very Large Telescope Interferometer are homogeneously reduced and calibrated. Geometric disk models are used to fit the observations to get spatial information about the disks. An automatic spectral decomposition pipeline is applied to analyze the shape of the silicate feature. We present the resulting data products in the form of an atlas, containing N band correlated and total spectra, visibilities, and differential phases. The majority of our data can be well fitted with a continuous disk model, except for a few objects, where a gapped model gives a better match. From the mid-infrared size-luminosity relation we find that disks around T Tauri stars are generally colder and more extended with respect to the stellar luminosity than disks around Herbig Ae stars. We find that in the innermost part of the disks (r<~1au) the silicate feature is generally weaker than in the outer parts, suggesting that in the inner parts the dust is substantially more processed. We analyze stellar multiplicity and find that in two systems (AB Aur and HD 72106) data suggest a new companion or asymmetric inner disk structure. We make predictions for the observability of our objects with the upcoming Multi-AperTure mid- Infrared SpectroScopic Experiment (MATISSE) instrument, supporting the practical preparations of future MATISSE observations of T Tauri stars.