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871. Linear polarization of AGN jets at 15GHz
ID:
ivo://CDS.VizieR/J/AJ/130/1389
Title:
Linear polarization of AGN jets at 15GHz
Short Name:
J/AJ/130/1389
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present first-epoch, milliarcsecond-scale linear polarization images at 15GHz of 133 jets associated with active galactic nuclei (AGNs) from the MOJAVE (Monitoring of Jets in Active Galactic Nuclei with VLBA Experiments) survey. MOJAVE is a long-term observational program to study the structure and evolution of relativistic outflows in AGNs. The sample consists of all known AGNs with Galactic latitude |b|>2.5{deg}, J2000.0 declination greater than -20{deg} and correlated 15GHz Very Long Baseline Array (VLBA) flux density exceeding 1.5Jy (2Jy for sources below the celestial equator) at any epoch during the period 1994-2003.
872. Linear Polarization of radio sources
ID:
ivo://CDS.VizieR/J/A+AS/39/379
Title:
Linear Polarization of radio sources
Short Name:
J/A+AS/39/379
Date:
21 Oct 2021
Publisher:
CDS
Description:
This catalogue is a compilation of all the data of linear polarization of radio sources published prior to December 1978. The catalogue contained 7224 data for 1510 radio sources. Polarization parameters derived from the data are also tabulated with other physical parameters.
873. Linelist of HCN and HNC
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.
874. Linelists for ammonia NH3, NH2D, ND2H, and ND3
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).
875. L1489IRS observed by the submillimeter array
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".
876. List of extra-galactic radio jets
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
877. LITTLE THINGS catalog of HI holes in 41 galaxies
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.
878. LkCa 15 and 2MASS J16100501-2132318 ALMa images
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.
879. LMC and Cen A 1.3-10GHz polarization behavior
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.
880. LMC N113 and N159W ALMA para-H_2_CO datacubes
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.