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- ID:
- ivo://CDS.VizieR/J/ApJ/710/L58
- Title:
- Coronal type II radio bursts in 2002
- Short Name:
- J/ApJ/710/L58
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Major space weather events such as solar flares and coronal mass ejections are usually accompanied by solar radio bursts, which can potentially be used for real-time space weather forecasts. Type II radio bursts are produced near the local plasma frequency and its harmonic by fast electrons accelerated by a shock wave moving through the corona and solar wind with a typical speed of ~1000km/s. The coronal bursts have dynamic spectra with frequency gradually falling with time and durations of several minutes. This Letter presents a new method developed to detect type II coronal radio bursts automatically and describes its implementation in an extended Automated Radio Burst Identification System (ARBIS 2). Preliminary tests of the method with spectra obtained in 2002 show that the performance of the current implementation is quite high, ~80%, while the probability of false positives is reasonably low, with one false positive per 100-200hr for high solar activity and less than one false event per 10000hr for low solar activity periods. The first automatically detected coronal type II radio burst is also presented.
- ID:
- ivo://CDS.VizieR/J/MNRAS/414/2005
- Title:
- Cosmic flows observations
- Short Name:
- J/MNRAS/414/2005
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The neutral hydrogen properties of 1822 galaxies are being studied with the Green Bank 100-m and the Parkes 64-m telescopes as part of the 'Cosmic Flows' programme. Observed parameters include systemic velocities, profile linewidths and integrated fluxes. The linewidth information can be combined with the optical and infrared photometry to obtain distances. The 1822 HI observations complement an inventory of archives.
- ID:
- ivo://CDS.VizieR/J/A+A/589/A60
- Title:
- CO, SO and H_2_CO images of AB Aur
- Short Name:
- J/A+A/589/A60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Transitional disks are structures of dust and gas around young stars with large inner cavities in which planet formation may occur. Lopsided dust distributions are observed in the dust continuum emission at millimeter wavelengths. These asymmetrical structures can be explained as being the result of an enhanced gas density vortex where the dust is trapped, potentially promoting the rapid growth to the planetesimal scale. AB Aur hosts a transitional disk with a clear horseshoe morphology which strongly suggests the presence of a dust trap. Our goal is to investigate its formation and the possible effects on the gas chemistry. We used the NOrthern Extended Millimeter Array (NOEMA) interferometer to image the 1mm continuum dust emission and the ^13^CO J=2->1, C^18^O J=2->1, SO J=5_6_->4_5_, and H_2_CO J=3_03_->2_02_. rotational lines.
- ID:
- ivo://CDS.VizieR/J/ApJS/196/18
- Title:
- CO survey of galactic molecular clouds. II.
- Short Name:
- J/ApJS/196/18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present fully sampled 38" resolution maps of the CO and ^13^CO J=2-1 lines in the molecular clouds toward the HII region complex W3. The maps cover a 2.0{deg}x1.67{deg} section of the galactic plane and span -70 to -20km/s (LSR) in velocity with a resolution of ~1.3km/s. The velocity range of the images includes all the gas in the Perseus spiral arm. We also present maps of CO J=3-2 emission for a 0.5{deg}x0.33{deg} area containing the HII regions W3 Main and W3(OH). The J=3-2 maps have velocity resolution of 0.87km/s and 24" angular resolution. Color figures display the peak line brightness temperature, the velocity-integrated intensity, and velocity channel maps for all three lines, and also the (CO/^13^CO) J=2-1 line intensity ratios as a function of velocity. The line intensity image cubes are made available in standard FITS format as electronically readable files. We compare our molecular line maps with the 1.1mm continuum image from the BOLOCAM Galactic Plane Survey (BGPS). From our ^13^CO image cube, we derive kinematic information for the 65 BGPS sources in the mapped field, in the form of Gaussian component fits.
- ID:
- ivo://CDS.VizieR/J/ApJS/209/39
- Title:
- CO survey of molecular clouds. III. Serpens
- Short Name:
- J/ApJS/209/39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We mapped ^12^CO and ^13^CO J=2-1 emission over 1.04deg^2^ of the Serpens molecular cloud with 38" spatial and 0.3km/s spectral resolution using the Arizona Radio Observatory Heinrich Hertz Submillimeter Telescope. Our maps resolve kinematic properties for the entire Serpens cloud. We also compare our velocity moment maps with known positions of young stellar objects (YSOs) and 1.1 mm continuum emission. We find that ^12^CO is self-absorbed and ^13^CO is optically thick in the Serpens core. Outside of the Serpens core, gas appears in filamentary structures having LSR velocities which are blueshifted by up to 2km/s relative to the 8km/s systemic velocity of the Serpens cloud. We show that the known Class I, flat, and Class II YSOs in the Serpens core most likely formed at the same spatial location and have since drifted apart. The spatial and velocity structure of the ^12^CO line ratios implies that a detailed three-dimensional radiative transfer model of the cloud will be necessary for full interpretation of our spectral data. The "starless cores" region of the cloud is likely to be the next site of star formation in Serpens.
- ID:
- ivo://CDS.VizieR/J/ApJS/214/7
- Title:
- CO survey of molecular clouds. IV. NGC 1333
- Short Name:
- J/ApJS/214/7
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We mapped the NGC 1333 section of the Perseus Molecular Cloud in the J=2-1 emission lines of ^12^CO and ^13^CO over a 50'x60' region (3.4x4.1pc at the cloud distance of 235pc), using the Arizona Radio Observatory Heinrich Hertz Submillimeter Telescope. The angular resolution is 38" (0.04pc) and velocity resolution is 0.3km/s. We compare our velocity moment maps with known positions of young stellar objects (YSOs) and (sub)millimeter dust continuum emission. The CO emission is brightest at the center of the cluster of YSOs, but is detected over the full extent of the mapped region at >=10xrms. The morphology of the CO channel maps shows a kinematically complex structure, with many elongated features extending from the YSO cluster outward by ~1pc. One notable feature appears as a narrow serpentine structure that curves and doubles back, with a total length of ~3pc. The ^13^CO velocity channel maps show evidence for many low-density cavities surrounded by partial shell-like structures, consistent with previous studies. Maps of the velocity moments show localized effects of bipolar outflows from embedded YSOs, as well as a large-scale velocity gradient around the central core of YSOs, suggestive of large-scale turbulent cloud motions determining the location of current star formation. The CO/^13^CO intensity ratios show the distribution of the CO opacity, which exhibits a complex kinematic structure. Identified YSOs are located mainly at the positions of greatest CO opacity.
- ID:
- ivo://CDS.VizieR/J/PASJ/56/313
- Title:
- 13CO survey of Mon & CMa molecular clouds
- Short Name:
- J/PASJ/56/313
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Through a large-scale 13^CO (J=1-0) survey toward a region in Monoceros and Canis Major, we have identified in total 115 clouds.
- ID:
- ivo://CDS.VizieR/J/A+AS/116/193
- Title:
- CO survey of spirals in Coma supercluster
- Short Name:
- J/A+AS/116/193
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations of the ^12^CO(J=1-0) line at 2.6mm of 65 galaxies located in the Coma supercluster region: 33 actually belong to the Coma supercluster while 32 are either foreground or background objects. These data have been obtained using the NRAO 12m telescope at Kitt Peak (United States), and for four galaxies, using the IRAM 30m telescope at Pico Veleta (Spain). Out of these 65 galaxies, 54 had never been observed in the CO(1-0) line; 49 have been detected by us, of which 37 are new detections. We give molecular gas masses deduced from the CO line integrated intensities, and upper limits for the 16 undetected objects, computed with a Galactic conversion factor N(H_2_)=2.3x10^20^I(CO) and H_0_=75km/s/Mpc.
- ID:
- ivo://CDS.VizieR/J/ApJS/191/232
- Title:
- CO survey of W51 molecular cloud
- Short Name:
- J/ApJS/191/232
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 38" resolution maps of the CO and ^13^COJ=2-1 lines in the molecular clouds toward the HII region complex W51. The maps cover a 1.25x1{deg} section of the galactic plane and span +30 to +85km/s (LSR) in velocity. The spectral resolution is ~1.3km/s. The velocity range of the images includes all the gas in the Sagittarius spiral arm. Color figures display the peak line brightness temperature, the velocity-integrated intensity, and 2km/s channel-averaged maps for both isotopologs, and also the CO/^13^COJ=2-1 line intensity ratio as a function of velocity. The CO and ^13^CO line intensity image cubes are made available in standard FITS format as electronically readable tables. We compare our molecular line maps with the 1.1mm continuum image from the BOLOCAM Galactic Plane Survey (BGPS; Aguirre et al. 2011ApJS..192....4A; Rosolowsky et al. 2010, Cat. J/ApJS/188/123). From our ^13^CO image cube, we derive kinematic information for the 99 BGPS sources in the mapped field in the form of Gaussian component fits. The integrated ^13^CO line intensity and the 1.1mm source flux density show only a modest degree of correlation for the 99 sources, likely due to a range of dust and gas physical conditions within the sources. However, the 1.1mm continuum surface brightness and the integrated ^13^CO line intensity for small regions containing single BGPS sources and molecular clouds show very good correlations in many cases.
