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- ID:
- ivo://CDS.VizieR/VI/121
- Title:
- Linelist of HCN and HNC
- Short Name:
- VI/121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We build an accurate database of 5200 HCN and HNC rotation-vibration energy levels, determined from existing laboratory data. 20000 energy levels in the Harris et al., 2002ApJ...578..657H (HPT), linelist are assigned approximate quantum numbers. These assignments, lab determined energy levels and HPT energy levels are incorporated in to a new energy level list. A new linelist is presented, in which frequencies are computed using the available lab determined energy levels, and the HPT ab initio energy levels otherwise.
- ID:
- ivo://CDS.VizieR/J/A+A/449/855
- Title:
- Linelists for ammonia NH3, NH2D, ND2H, and ND3
- Short Name:
- J/A+A/449/855
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Linelists with calculated line positions and line intensities for ammonia (NH_3_) molecule and its three deuterated variants NH_2_D, ND_2_H, and ND_3_ with quadrupole coupling hyperfine splittings. Lines in linelists are formatted as in the JPL data base (Pickett, Poynter, Cohen et al. 1998, J. Quant. Spectrosc. Radiat. Transfer, 60, 883).
- ID:
- ivo://CDS.VizieR/J/A+A/475/915
- Title:
- L1489IRS observed by the submillimeter array
- Short Name:
- J/A+A/475/915
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Submillimeter Array observations of the Young Stellar Object L1489IRS (IRAS 04016+2610). These include images of the continuum at 267 GHz (1.12 mm) and line emission of the HCO+ J=3-2 transition at 267.55762 GHz. The HCO+ image is available in two different (u,v)-weighting schemes, natural and uniform, optimizing for S/N and resolution respectively. The continuum image is only available in uniform weighting. The synthesized beam size is 1".
- ID:
- ivo://CDS.VizieR/J/A+A/381/757
- Title:
- List of extra-galactic radio jets
- Short Name:
- J/A+A/381/757
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Table 1 lists 661 radio sources with detected radio jets known to us prior to the end of December 2000
- ID:
- ivo://CDS.VizieR/J/AJ/160/66
- Title:
- LITTLE THINGS catalog of HI holes in 41 galaxies
- Short Name:
- J/AJ/160/66
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of holes and shells in the neutral atomic hydrogen (HI) of 41 gas-rich dwarf galaxies in LITTLE THINGS (Local Irregulars That Trace Luminosity Extremes, The HI Nearby Galaxy Survey). We analyzed their properties as part of an investigation into the relation between star formation and structures and kinematics in the HI of small galaxies. We confirmed 306 holes between 38pc (our resolution limit) and 2.3kpc, with expansion velocities up to 30km/s. The global star formation rates (SFRs) measured by H{alpha} and far-UV (FUV) emission are consistent with those estimated from the energy required to create the cataloged holes in our sample. Although we found no obvious correlation between global star forming regions (SFRs) and the HI surface and volume porosities of our sample, two of the four galaxies with the lowest porosity and the two galaxies with the highest porosity have no recent star formation as measured by H{alpha} and FUV emission.
- ID:
- ivo://CDS.VizieR/J/A+A/639/A121
- Title:
- LkCa 15 and 2MASS J16100501-2132318 ALMa images
- Short Name:
- J/A+A/639/A121
- Date:
- 23 Mar 2022 16:30:37
- Publisher:
- CDS
- Description:
- We present high-resolution millimeter continuum ALMA observations of the disks around the T Tauri stars LkCa 15 and 2MASS J16100501-2132318 (hereafter, J1610). These transition disks host dust-depleted inner regions, which have possibly been carved by massive planets, and they are of prime interest to the study of the imprints of planet-disk interactions. While at moderate angular resolution, they appear as a broad ring surrounding a cavity, the continuum emission resolves into multiple rings at a resolution of ~60x40,mas (~7.5au for LkCa 15, ~6au for J1610) and ~7uJy/beam rms at 1.3mm. In addition to a broad extended component, LkCa 15 and J1610 host three and two narrow rings, respectively, with two bright rings in LkCa 15 being radially resolved. LkCa 15 possibly hosts another faint ring close to the outer edge of the mm emission. The rings look marginally optically thick, with peak optical depths of ~0.5 (neglecting scattering), in agreement with high angular resolution observations of full disks. We performed hydrodynamical simulations with an embedded, sub-Jovian-mass planet and show that the observed multi-ringed substructure can be qualitatively explained as the outcome of the planet-disk interaction. We note, however, that the choice of the disk cooling timescale alone can significantly impact the resulting gas and dust distributions around the planet, leading to different numbers of rings and gaps and different spacings between them. We propose that the massive outer disk regions of transition disks are favorable places for planetesimals, and possibly second-generation planet formation of objects with a lower mass than the planets carving the inner cavity (typically few M_Jup_), and that the annular substructures observed in LkCa~15 and J1610 may be indicative of planetary core formation within dust-rich pressure traps. Current observations are compatible with other mechanisms contributing to the origin of the observed substructures, in particular with regard to narrow rings generated (or facilitated) at the edge of the CO and N_2_ snowlines.
- ID:
- ivo://CDS.VizieR/J/ApJ/825/59
- Title:
- LMC and Cen A 1.3-10GHz polarization behavior
- Short Name:
- J/ApJ/825/59
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a broadband polarization analysis of 36 discrete polarized radio sources over a very broad, densely sampled frequency band. Our sample was selected on the basis of polarization behavior apparent in narrowband archival data at 1.4GHz: half the sample shows complicated frequency-dependent polarization behavior (i.e., Faraday complexity) at these frequencies, while half shows comparatively simple behavior (i.e., they appear Faraday simple). We re-observed the sample using the Australia Telescope Compact Array in full polarization, with 6GHz of densely sampled frequency coverage spanning 1.3-10GHz. We have devised a general polarization modeling technique that allows us to identify multiple polarized emission components in a source, and to characterize their properties. We detect Faraday complex behavior in almost every source in our sample. Several sources exhibit particularly remarkable polarization behavior. By comparing our new and archival data, we have identified temporal variability in the broadband integrated polarization spectra of some sources. In a number of cases, the characteristics of the polarized emission components, including the range of Faraday depths over which they emit, their temporal variability, spectral index, and the linear extent of the source, allow us to argue that the spectropolarimetric data encode information about the magneto-ionic environment of active galactic nuclei themselves. Furthermore, the data place direct constraints on the geometry and magneto-ionic structure of this material. We discuss the consequences of restricted frequency bands on the detection and interpretation of polarization structures, and the implications for upcoming spectropolarimetric surveys.
- ID:
- ivo://CDS.VizieR/J/A+A/655/A12
- Title:
- LMC N113 and N159W ALMA para-H_2_CO datacubes
- Short Name:
- J/A+A/655/A12
- Date:
- 07 Mar 2022 07:15:12
- Publisher:
- CDS
- Description:
- We mapped the kinetic temperature structure of two massive star-forming regions, N113 and N159W, in the Large Magellanic Cloud (LMC). We have used ~1.6" (~0.4pc) resolution measurements of the para-H_2_CO J_KaKc_=3_03_-2_02_, 3_22_-2_21_, and 3_21_-2_20_ transitions near 218.5GHz to constrain RADEX non local thermodynamic equilibrium models of the physical conditions. The gas kinetic temperatures derived from the para-H_2_CO line ratios 3_22_-2_21_/3_03_-2_02_ and 3_21_-2_20_/3_03_-2_02_ range from 28 to 105K in N113 and 29 to 68K in N159W. Distributions of the dense gas traced by para-H_2_CO agree with those of the 1.3mm dust and Spitzer 8.0um emission, but they do not significantly correlate with the H emission. The high kinetic temperatures (T_kin_>~50K) of the dense gas traced by para-H_2_CO appear to be correlated with the embedded infrared sources inside the clouds and/or young stellar objects in the N113 and N159W regions. The lower temperatures (T_kin_<50K) were measured at the outskirts of the H_2_CO-bearing distributions of both N113 and N159W. It seems that the kinetic temperatures of the dense gas traced by para-H_2_CO are weakly affected by the external sources of the H{alpha} emission. The non thermal velocity dispersions of para-H_2_CO are well correlated with the gas kinetic temperatures in the N113 region, implying that the higher kinetic temperature traced by para-H_2_CO is related to turbulence on a ~0.4pc scale. The dense gas heating appears to be dominated by internal star formation activity, radiation, and/or turbulence. It seems that the mechanism heating the dense gas of the star-forming regions in the LMC is consistent with that in Galactic massive star-forming regions located in the Galactic plane.
- ID:
- ivo://CDS.VizieR/J/MNRAS/448/3731
- Title:
- Local Group dSph radio survey with ATCA
- Short Name:
- J/MNRAS/448/3731
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Dwarf spheroidal (dSph) galaxies are key objects in near-field cosmology, especially in connection to the study of galaxy formation and evolution at small scales. In addition, dSphs are optimal targets to investigate the nature of dark matter. However, while we begin to have deep optical photometric observations of the stellar population in these objects, little is known so far about their diffuse emission at any observing frequency, and hence on thermal and non-thermal plasma possibly residing within dSphs. In this paper, we present deep radio observations of six local dSphs performed with the Australia Telescope Compact Array (ATCA) at 16cm wavelength. We mosaicked a region of radius of about 1{deg} around three 'classical' dSphs, Carina, Fornax, and Sculptor, and of about half of degree around three 'ultrafaint' dSphs, BootesII, Segue2, and Hercules. The rms noise level is below 0.05 mJy for all the maps. The restoring beams full width at half-maximum ranged from 4.2"x2.5" to 30.0"x2.1" in the most elongated case. A catalogue including the 1392 sources detected in the six dSph fields is reported. The main properties of the background sources are discussed, with positions and fluxes of brightest objects compared with the FIRST, NVSS, and SUMSS observations of the same fields. The observed population of radio emitters in these fields is dominated by synchrotron sources. We compute the associated source number counts at 2GHz down to fluxes of 0.25mJy, which prove to be in agreement with AGN count models.
