- ID:
- ivo://CDS.VizieR/J/AZh/94/1003
- Title:
- Infrared morphology of HII regions
- Short Name:
- J/AZh/94/1003
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A search for infrared ring nebulae associated with regions of ionized hydrogen has been carried out. The New GPS Very Large Array survey at 20 cm forms the basis of the search, together with observations obtained with the Spitzer Space Telescope at 8 and 24um and the Herschel Space Telescope at 70um. Objects having ring-like morphologies at 8um and displaying extended emission at 20cm were selected visually. Emission at 24um having the form of an inner ring or central peak is also observed in the selected objects. A catalog of 99 ring nebulae whose shapes at 8 and 70um are well approximated by ellipses has been compiled. The catalog contains 32 objects whose shapes are close to circular (eccentricities of the fitted ellipses at 8um no greater than 0.6, angular radius exceeding 20"). These objects are promising for comparisons with the results of one-dimensional hydrodynamical simulations of expanding regions of ionized hydrogen.
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Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/616/A111
- Title:
- Integral-shaped filament NH_3_ observations
- Short Name:
- J/A+A/616/A111
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recent observations suggest a scenario in which filamentary structures in the interstellar medium represent the first step towards clumps/cores and eventually star formation. The densest filaments would then fragment into prestellar cores owing to gravitational instability. We seek to understand the roles filamentary structures play in high-mass star formation. We mapped the integral-shaped filament (ISF) located at the northern end of the Orion A molecular cloud in NH_3_ (1, 1) and (2, 2). The observations were made using the 25m radio telescope operated by the Xinjiang Astronomical Observatory, Chinese Academy of Sciences. The whole filamentary structure, about 1.2{deg}x0.6{deg}, is uniformly and fully sampled. We investigate the morphology, fragmentation, kinematics, and temperature properties in this region. We find that the morphology revealed by the map of velocity-integrated intensity of the NH_3_ (1, 1) line is closely associated with the dust ridge revealed by the Herschel Space Observatory. We identify 6 "lumps" related to the well known OMC-1 to 5 and 11 "sub-clumps" within the map. The clumps and sub-clumps are separated not randomly but in roughly equal intervals along the ISF. The average spacing of clumps is 11.30'+/-1.31' (1.36+/-0.16pc) and the average spacing of sub-clumps is 7.18'+/-1.19' (0.86+/-0.14pc). These spacings agree well with the predicted values of the thermal (0.86 pc) and turbulent sausage instability (1.43pc) by adopting a cylindric geometry of the ISF with an inclination of 60{deg} with respect to the line of sight. We also find a velocity gradient of about 0.6km/s/pc that runs along the ISF which likely arises from an overall rotation of the Orion A molecular cloud. The inferred ratio between rotational and gravitational energy is well below unity. Furthermore, fluctuations are seen in the centroid velocity diagram along the ISF. The OMC-1 to 5 clouds are located close to the local extrema of the fluctuations, which suggests that there exist gas flows associated with these clumps in the ISF. The derived NH_3_ (1, 1) and (2, 2) rotation temperatures in the OMC-1 are about 30-40K while lower temperatures (below 20K) are obtained in the northern and southern parts of the ISF. In OMC-2, OMC-3, and the northern part of OMC-4, we find higher and lower temperatures at the boundaries and in the interior, respectively.
- ID:
- ivo://CDS.VizieR/J/MNRAS/407/2475
- Title:
- Ionized gas in E/S0 galaxies with dust lanes
- Short Name:
- J/MNRAS/407/2475
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of multicolour observations of 30 E/S0 galaxies with dust lanes. For each galaxy we obtained broad-band images and narrow-band images using interference filters isolating the H{alpha}+[NII] emission lines to derive the amount and morphology of dust and ionized gas. To improve the wavelength coverage we retrieved data from the Sloan Digital Sky Survey and Two Micron All Sky Survey and combined these with our data. Ionized gas is detected in 25 galaxies and shows in most cases a smooth morphology, although knots and filamentary structure are also observed in some objects.
- ID:
- ivo://CDS.VizieR/J/AJ/116/2728
- Title:
- I photometry of early-type galaxies
- Short Name:
- J/AJ/116/2728
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As part of a project to compare the fundamental plane and Tully-Fisher distance scales, we present here I-band CCD photometry for 636 early-type galaxies in eight clusters and groups of galaxies. These are the A262, A1367, Coma (A1656), A2634, Cancer and Pegasus Clusters, and the NGC 383 and NGC 507 Groups. Sample selection, cluster properties, and cluster membership assignment criteria are discussed. We present photometric parameters that are used in the fundamental plane relation, the effective radius r_e_, and the effective surface brightness {mu}_e_, as derived from a r^1/4^ fit to the observed radial photometric profile of each galaxy. A comparison with similar data found in the literature for the Coma Cluster shows that large systematic uncertainties can be introduced in the measurement of r_e_ and {mu}_e_ by the particular method used to derive those parameters. However, the particular combination of these two parameters that enters in the fundamental plane relation is a quantity that can be measured with high accuracy.
- ID:
- ivo://CDS.VizieR/J/ApJ/727/1
- Title:
- IRAC/MUSYC SIMPLE survey
- Short Name:
- J/ApJ/727/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Spitzer IRAC/MUSYC Public Legacy Survey in the Extended CDF-South (SIMPLE), which consists of deep IRAC observations covering the ~1600arcmin^2^ area surrounding GOODS-S. The limiting magnitudes of the SIMPLE IRAC mosaics typically are 23.8, 23.6, 21.9, and 21.7, at 3.6um, 4.5um, 5.8um, and 8.0um, respectively (5{sigma} total point source magnitudes in AB). The SIMPLE IRAC images are combined with the 10'x15' GOODS IRAC mosaics in the center. We give detailed descriptions of the observations, data reduction, and properties of the final images, as well as the detection and photometry methods used to build a catalog. Using published optical and near-infrared data from the Multiwavelength Survey by Yale-Chile (MUSYC), we construct an IRAC-selected catalog, containing photometry in UBVRIz'JHK, [3.6um], [4.5um], [5.8um], and [8.0um]. The catalog contains 43,782 sources with S/N>5 at 3.6um, 19,993 of which have 13-band photometry. We compare this catalog to the publicly available MUSYC and FIREWORKS catalogs and discuss the differences. Using a high signal-to-noise sub-sample of 3391 sources with ([3.6]+[4.5])/2<21.2, we investigate the star formation rate history of massive galaxies out to z~1.8. We find that at z~1.8 at least 30+/-7% of the most massive galaxies (M*>10^11^M_{sun}_) are passively evolving, in agreement with earlier results from surveys covering less area.
- ID:
- ivo://CDS.VizieR/J/AJ/154/201
- Title:
- IR properties of stellar bowshock nebulae
- Short Name:
- J/AJ/154/201
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Arcuate infrared nebulae are ubiquitous throughout the Galactic Plane and are candidates for partial shells, bubbles, or bowshocks produced by massive runaway stars. We tabulate infrared photometry for 709 such objects using images from the Spitzer Space Telescope, the Wide-field Infrared Explorer, and the Herschel Space Observatory (HSO). Of the 709 objects identified at 24 or 22 {mu}m, 422 are detected at the HSO 70 {mu}m bandpass. Of these, only 39 are detected at HSO 160 {mu}m. The 70 {mu}m peak surface brightnesses are 0.5-2.5 Jyr/arcmin^2^. Color temperatures calculated from the 24 to 70 {mu}m ratios range from 80 to 400 K. Color temperatures from 70 to 160 {mu}m ratios are systematically lower, 40-200 K. Both of these temperature are, on average, 75% higher than the nominal temperatures derived by assuming that dust is in steady-state radiative equilibrium. This may be evidence of stellar wind bowshocks sweeping up and heating-possibly fragmenting but not destroying-interstellar dust. Infrared luminosity correlates with standoff distance, R_0_, as predicted by published hydrodynamical models. Infrared spectral energy distributions are consistent with interstellar dust exposed to either single radiant energy density, U=10^3^-10^5^ (in more than half of the objects) or a range of radiant energy densities U_min_=25 to U_max_=10^3^-10^5^ times the mean interstellar value for the remainder. Hence, the central OB stars dominate the energetics, making these enticing laboratories for testing dust models in constrained radiation environments. The spectral energy densities are consistent with polycyclic aromatic hydrocarbon fractions q_PAH_~<1% in most objects.
- ID:
- ivo://CDS.VizieR/J/A+A/397/177
- Title:
- IR star clusters and stellar groups catalog
- Short Name:
- J/A+A/397/177
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We compiled a catalogue of infrared star clusters in the Galaxy, which are most of them embedded. It condenses the growing literature information. We also include in the sample infrared stellar groups which are less dense than star clusters, such as those embedded in the dark clouds Taurus-Auriga and Chamaleon I. We provide galactic and equatorial coordinates, angular dimensions, different designations and related objects such as nebulae. A total of 189 infrared clusters and 87 embedded stellar groups are included. A fraction of 25% of the embedded clusters are projected close to each other in pair or triplet systems, indicating that multiplicity plays an important role in star cluster formation.
- ID:
- ivo://CDS.VizieR/VII/77
- Title:
- Isolated Pairs of Galaxies in Northern Hemisphere
- Short Name:
- VII/77
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog is a compilation of observational data for 603 isolated pairs of galaxies with component magnitudes brighter than 15.7 and north of declination -3 degrees. The catalog includes pair numbers and component letters, coordinates, apparent magnitudes, radial velocities, major axes and eccentricities, Hubble classifications, spectral types, and distances between components.
- ID:
- ivo://CDS.VizieR/J/MNRAS/453/4264
- Title:
- JCMT Plane Survey: l=30{deg} field
- Short Name:
- J/MNRAS/453/4264
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present early results from the JCMT (James Clerk Maxwell Telescope) Plane Survey (JPS), which has surveyed the northern inner Galactic plane between longitudes l=7{deg} and l=63{deg} in the 850-{mu}m continuum with SCUBA-2 (Submm Common-User Bolometer Array 2), as part of the JCMT Legacy Survey programme. Data from the l=30{deg} survey region, which contains the massive-star-forming regions W43 and G29.96, are analysed after approximately 40 percent of the observations had been completed. The pixel-to-pixel noise is found to be 19mJy/beam after a smooth over the beam area, and the projected equivalent noise levels in the final survey are expected to be around 10mJy/beam. An initial extraction of compact sources was performed using the FellWalker method, resulting in the detection of 1029 sources above a 5{sigma} surface-brightness threshold. The completeness limits in these data are estimated to be around 0.2Jy/beam (peak flux density) and 0.8 Jy (integrated flux density) and are therefore probably already dominated by source confusion in this relatively crowded section of the survey. The flux densities of extracted compact sources are consistent with those of matching detections in the shallower APEX (Atacama Pathfinder Experiment) Telescope Large Area Survey of the Galaxy (ATLASGAL) survey. We analyse the virial and evolutionary state of the detected clumps in the W43 star-forming complex and find that they appear younger than the Galactic-plane average.
- ID:
- ivo://CDS.VizieR/J/ApJ/868/133
- Title:
- j-M relation for disk and bulge type galaxies
- Short Name:
- J/ApJ/868/133
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We show that the stellar specific angular momentum j_*_, mass M_*_, and bulge fraction {beta}_*_ of normal galaxies of all morphological types are consistent with a simple model based on a linear superposition of independent disks and bulges. In this model, disks and bulges follow scaling relations of the form j_*_d{propto}M_*_d^{alpha}^ and j_*_b{propto}M_*_b^{alpha}^ with {alpha}=0.67+/-0.07 but offset from each other by a factor of 8+/-2 over the mass range 8.9<=log(M_*/M_{sun})<=11.8. Separate fits for disks and bulges alone give {alpha}=0.58+/-0.10 and {alpha}=0.83+/-0.16, respectively. This model correctly predicts that galaxies follow a curved 2D surface in the 3D space of log(j_*_), log(M_*_), and {beta}_*_. We find no statistically significant indication that galaxies with classical and pseudo bulges follow different relations in this space, although some differences are permitted within the observed scatter and the inherent uncertainties in decomposing galaxies into disks and bulges. As a byproduct of this analysis, we show that the j_*_-M_*_ scaling relations for disk-dominated galaxies from several previous studies are in excellent agreement with each other. In addition, we resolve some conflicting claims about the {beta}_*_ dependence of the j_*_-M_*_ scaling relations. The results presented here reinforce and extend our earlier suggestion that the distribution of galaxies with different {beta}_*_ in the j_*_-M_*_ diagram constitutes an objective, physically motivated alternative to subjective classification schemes such as the Hubble sequence.
