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- ID:
- ivo://CDS.VizieR/J/A+A/242/401
- Title:
- Walraven photometry of WX Hyi
- Short Name:
- J/A+A/242/401
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The SU UMa-type dwarf nova WX Hyi was observed in the 5 passbands VBLUW (544, 430, 384, 362 and 324nm) during 15 nights on the 90cm telescope at ESO (La Silla), between July and November 1988, with an integration time of 16s.
24463. W Aql APEX spectrum
- ID:
- ivo://CDS.VizieR/J/A+A/642/A20
- Title:
- W Aql APEX spectrum
- Short Name:
- J/A+A/642/A20
- Date:
- 23 Mar 2022 16:31:40
- Publisher:
- CDS
- Description:
- W Aql is an asymptotic giant branch (AGB) star with an atmospheric elemental abundance ratio C/O~=0.98. It has previously been reported to have circumstellar molecular abundances intermediate between those of M-type and C-type AGB stars, which respectively have C/O<1 and C/O>1. This intermediate status is considered typical for S-type stars, although our understanding of the chemical content of their circumstellar envelopes is currently rather limited. We wish to assess the reported intermediate status of W Aql by analysing the line emission of molecules that have not been observed towards this star before. We have performed observations in the frequency range 159-268GHz with the SEPIA/B5 and PI230 instruments on the APEX telescope. We make abundance estimates through direct comparison to available spectra towards a number of well-studied AGB stars and based on rotational diagram analysis in the case of one molecule. From a compilation of our abundance estimates and those found in the literature for two M-type (R Dor, IK Tau), two S-type ({chi} Cyg, W Aql), and two C-type stars (V Aql, IRC +10 216), we conclude that W Aql's circumstellar environment appears considerably closer to that of a C-type AGB star than to that of an M-type AGB star. In particular, we detect emission from C_2_H, SiC_2_, SiN, and HC_3_N, molecules previously only detected towards the circumstellar environment of C-type stars. This conclusion, based on the chemistry of the gaseous component of the circumstellar environment, is further supported by reports in the literature on the presence of atmospheric molecular bands and spectral features of dust species which are typical for C-type AGB stars. Although our observations mainly trace species in the outer regions of the circumstellar environment, our conclusion matches closely that based on recent chemical equilibrium models for the inner wind of S-type stars: the atmospheric and circumstellar chemistry of S-type stars likely resembles that of C-type AGB stars much more closely than that of M-type AGB stars. Further observational investigation of the gaseous circumstellar chemistry of S-type stars is required to characterise its dependence on the atmospheric C/O. Non-equilibrium chemical models of the circumstellar environment of AGB stars need to address the particular class of S-type stars and the chemical variety that is induced by the range in atmospheric C/O.
- ID:
- ivo://CDS.VizieR/J/A+A/410/597
- Title:
- Warm dust near methanol masers
- Short Name:
- J/A+A/410/597
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Continuum emission at 450 and 850{mu}m from warm dust has been mapped in the fields of 71 methanol masers. Within these fields lie 30 centimetre-wave radio continuum sources and an additional 13 methanol maser sites. Sub-mm emission is detected at all but one of the maser sites, confirming the association of methanol maser emission with deeply embedded objects. Measured bolometric luminosities confirm that methanol maser emission is an excellent signpost of high-mass star formation. Examples of nearby isolated maserless dust cores may be harbouring massive protostars at an earlier evolutionary stage.
- ID:
- ivo://CDS.VizieR/J/A+AS/70/95
- Title:
- Warm IRAS sources. I. AGN candidates
- Short Name:
- J/A+AS/70/95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have previously shown that a blue (warm) 60 to 25{mu}m infrared colour provides a powerful parameter for discriminating between AGNs and normal galaxies and that the far-IR spectrum is therefore an efficient tool for finding new AGNs (de Grijp et al., 1985Natur.314..140D) Here we present a list of such AGN candidates based on warm IR sources from the IRAS Point Source Catalogue (PSC, Cat. II/125). Identification data and finding charts are also given. In addition the list of warm IRAS sources is supplemented by a compendium of data from the IRAS PSC on detected sources identified with previously known AGNs whose infrared spectra do not bring them within our colour selection criterion
24466. Warm IRAS sources. II.
- ID:
- ivo://CDS.VizieR/J/A+AS/96/389
- Title:
- Warm IRAS sources. II.
- Short Name:
- J/A+AS/96/389
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical spectra for a sample of 563 high-latitude IRAS sources selected from the Point Source Catalog to have relatively warm 25 to 60 micron colours. We have shown this selection criterion to be an efficient indicator for finding Seyfert galaxies. Plots of the optical spectra are shown and the fluxes of the strongest emission lines in these spectra are tabulated. After excluding 128 sources which are clearly galactic foreground objects, we obtained spectroscopic information for 358 extragalactic objects. Emission-line ratios have been used to classify these objects, resulting in 80 Seyfert 1, 141 Seyfert 2 and 133 HII-type objects. In comparison with samples of active nuclei selected in other ways, about 50% of known Seyfert nuclei are included by our colour criteria. This fraction is larger for high luminosities, reaching 80% for quasar luminosities. For lower-luminosity objects, contamination by the host galaxies becomes important and the sample becomes seriously incomplete. It should be moderately complete and representative for core luminosities greater than 10^23.5^W/Hz at 12m. Finally, the infrared luminosity function for each type of object is derived; the shapes for Seyfert 1 and 2 nuclei are identical, with a type 2/type 1 space-density ratio of 3.0. Our census is consistent with an obscuration scheme for producing both types of object from a single parent population, though the origin of excess cool IR radiation Irom many Seyferts is still unclear. We note the appearance of an apparent type II supernova in IRAS 0225-103 observed in 1985 September. Its spectrum suggests that it was observed between 1 and 2 months after maximum, perhaps in a "plateau" phase.
24467. Warm IRAS sources. IV.
- ID:
- ivo://CDS.VizieR/J/A+AS/108/61
- Title:
- Warm IRAS sources. IV.
- Short Name:
- J/A+AS/108/61
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a list of objects observed to have extended line emission in our spectroscopic survey of infrared-warm AGN. Slit spectroscopic data were obtained for 225 galaxies identified with objects in our compendium of warm sources from the IRAS Point Source Catalog. Of these, 44 have spatially-resolved emission-line regions along the (arbitrarily placed) slit direction. Measured (projected) linear sizes of the ionized gas regions extend to >10kpc. In the case of the IRAS Seyfert galaxies the spatially extended line emission appears to have a lower ionization state than the nuclear emission. This contrasts with the warm IRAS starbust galaxies for which there is no significant difference between the ionization states of the nuclear and extended emission. For the starburst galaxies, there is a relation between the extent of star formation as seen at H{alpha} and the far-IR colors, with more compact bursts having "warmer" colors.
- ID:
- ivo://CDS.VizieR/J/A+A/588/A131
- Title:
- Warm ISM in the Sagittarius A Complex
- Short Name:
- J/A+A/588/A131
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate the spatial and spectral distribution of the local standard of rest (LSR) velocity resolved submillimetre emission from the warm (25-90K) gas in the Sgr A Complex, located in the Galactic centre. We present large-scale submillimetre heterodyne observations towards the Sgr A Complex covering ~300-arcmin2. These data were obtained in the frame of the Herschel EXtraGALactic guaranteed time key program (HEXGAL) with the Herschel-HIFI satellite and are complemented with submillimetre observations obtained with the NANTEN2/SMART telescope as part of the NANTEN2/SMART Central Nuclear Zone Survey. The observed species are CO(J=4-3) at 461.0GHz observed with the NANTEN2/SMART telescope, and [CI] 3P1-3P0 at 492.2GHz, [CI] 3P2-3P1 at 809.3GHz, [NII] 3P1-3P0 at 1461.1GHz, and [CII] 2P3/2-2P1/2 at 1900.5GHz observed with the Herschel-HIFI satellite. The observations are presented in a 1km/s spectral resolution and a spatial resolution ranging from 46-arcsec to 28-arcsec. The spectral coverage of the three lower frequency lines is +/-200km/s, while in the two high frequency lines, the upper LSR velocity limit is +94km/s and +145km/s for the [NII] and [CII] lines, respectively. The spatial distribution of the emission in all lines is very widespread. The bulk of the carbon monoxide emission is found towards Galactic latitudes below the Galactic plane, and all the known molecular clouds are identified. Both neutral atomic carbon lines have their brightest emission associated with the +50km/s cloud. Their spatial distribution at this LSR velocity describes a crescent-shape structure, which is probably the result of interaction with the energetic event (one or several supernovae explosions) that gave origin to the non-thermal Sgr A-East source. The [CII] and [NII] emissions have most of their flux associated with the thermal arched-filaments and the H region and bright spots in [CII] emission towards the central nuclear disk (CND) are detected. Warm Gas at very high (|Vlsr|>100km/s) LSR velocities is also detected towards the line of sight to the Sgr A Complex, and it is most probably located outside the region, in the X1 orbits.
- ID:
- ivo://CDS.VizieR/J/ApJS/255/6
- Title:
- Warm Jupiters in TESS FFIs 1st year (2018-2019 July)
- Short Name:
- J/ApJS/255/6
- Date:
- 06 Dec 2021 19:57:22
- Publisher:
- CDS
- Description:
- Warm Jupiters-defined here as planets larger than 6 Earth radii with orbital periods of 8-200 days-are a key missing piece in our understanding of how planetary systems form and evolve. It is currently debated whether Warm Jupiters form in situ, undergo disk or high-eccentricity tidal migration, or have a mixture of origin channels. These different classes of origin channels lead to different expectations for Warm Jupiters' properties, which are currently difficult to evaluate due to the small sample size. We take advantage of the Transiting Exoplanet Survey Satellite (TESS) survey and systematically search for Warm Jupiter candidates around main-sequence host stars brighter than the TESS-band magnitude of 12 in the full-frame images in Year 1 of the TESS Prime Mission data. We introduce a catalog of 55 Warm Jupiter candidates, including 19 candidates that were not originally released as TESS objects of interest by the TESS team. We fit their TESS light curves, characterize their eccentricities and transit-timing variations, and prioritize a list for ground-based follow-up and TESS Extended Mission observations. Using hierarchical Bayesian modeling, we find the preliminary eccentricity distributions of our Warm-Jupiter-candidate catalog using a beta distribution, a Rayleigh distribution, and a two-component Gaussian distribution as the functional forms of the eccentricity distribution. Additional follow-up observations will be required to clean the sample of false positives for a full statistical study, derive the orbital solutions to break the eccentricity degeneracy, and provide mass measurements.
- ID:
- ivo://CDS.VizieR/J/AJ/156/295
- Title:
- Warm molecular hydrogen in nearby LIRGs
- Short Name:
- J/AJ/156/295
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Mid-infrared molecular hydrogen (H_2_) emission is a powerful cooling agent in galaxy mergers and in radio galaxies; it is a potential key tracer of gas evolution and energy dissipation associated with mergers, star formation, and accretion onto supermassive black holes. We detect mid-IR H_2_ line emission in at least one rotational transition in 91% of the 214 Luminous Infrared Galaxies (LIRGs) observed with Spitzer as part of the Great Observatories All-sky LIRG Survey. We use H_2_ excitation diagrams to estimate the range of masses and temperatures of warm molecular gas in these galaxies. We find that LIRGs in which the IR emission originates mostly from the Active Galactic Nuclei (AGN) have about 100 K higher H_2_ mass-averaged excitation temperatures than LIRGs in which the IR emission originates mostly from star formation. Between 10% and 15% of LIRGs have H_2_ emission lines that are sufficiently broad to be resolved or partially resolved by the high-resolution modules of Spitzer's Infrared Spectrograph (IRS). Those sources tend to be mergers and contain AGN. This suggests that a significant fraction of the H_2_ line emission is powered by AGN activity through X-rays, cosmic rays, and turbulence. We find a statistically significant correlation between the kinetic energy in the H_2_ gas and the H_2_ to IR luminosity ratio. The sources with the largest warm gas kinetic energies are mergers. We speculate that mergers increase the production of bulk inflows leading to observable broad H_2_ profiles and possibly denser gas.