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- ID:
- ivo://CDS.VizieR/VII/64
- Title:
- CO Observations of Galaxies
- Short Name:
- VII/64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog is a complete summary of all observations of CO isotopes in galaxies up to spring 1984. It consists of seven tables. Refs.dat describes the reference for CO observations of galaxies. Telescop.dat describes the properties of the telescopes used for observations. Detect.dat and uprlmits.dat contain a compilation of data on galaxies that have been observed in CO. Most of the characteristics listed here are observed properties. The detected galaxies are listed first, followed by galaxies with upper limits. Upper limits are given for detected galaxies if the detection is disputed or if the limits refer to transitions or regions that have not yet been detected. Temp.dat is a comparison of the antenna temperature scales used in the references in this catalog. Maps.dat lists the coverage, resolution, observed structure of CO maps of galaxies, and notes.dat contains notes to tables.
- ID:
- ivo://CDS.VizieR/J/ApJS/178/56
- Title:
- CO observations of LMC Giant Molecular clouds
- Short Name:
- J/ApJS/178/56
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The second survey of the molecular clouds in the Large Magellanic Cloud in ^12^CO(J=1-0) was carried out by NANTEN. The sensitivity of this survey is twice as high as that of the previous NANTEN survey, leading to a detection of molecular clouds with M_CO_>~2x10^4^solMass. We identified 272 molecular clouds, 230 of which are detected at three or more observed positions. We derived the physical properties, such as size, line width, and virial mass, of the 164 GMCs (Giant Molecular clouds) that have an extent more than the beam size of NANTEN in both the major and minor axes.
- ID:
- ivo://CDS.VizieR/J/ApJS/197/16
- Title:
- CO observations of LMC molecular clouds (MAGMA).
- Short Name:
- J/ApJS/197/16
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the properties of an extensive sample of molecular clouds in the Large Magellanic Cloud (LMC) mapped at 11pc resolution in the CO(1-0) line. Targets were chosen based on a limiting CO flux and peak brightness as measured by the NANTEN survey. The observations were conducted with the ATNF Mopra Telescope as part of the Magellanic Mopra Assessment. We identify clouds as regions of connected CO emission and find that the distributions of cloud sizes, fluxes, and masses are sensitive to the choice of decomposition parameters.
- ID:
- ivo://CDS.VizieR/J/A+A/627/A107
- Title:
- CO observations of major merger pairs at z=0
- Short Name:
- J/A+A/627/A107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present CO observations of 78 spiral galaxies in local merger pairs. These galaxies represent a subsample of a Ks-band-selected sample consisting of 88 close major-merger pairs (HKPAIRs), 44 spiral-spiral (S+S) pairs, and 44 spiral-elliptical (S+E) pairs, with separation <20h^-1^kpc and mass ratio <2.5. For all objects, the star formation rate (SFR) and dust mass were derived from Herschel PACS and SPIRE data, and the atomic gas mass, MHI, from the Green Bank Telescope HI observations. The complete data set allows us to study the relation between gas (atomic and molecular) mass, dust mass, and SFR in merger galaxies. We derive the molecular gas fraction (M_H2_/M*), molecular-to-atomic gas mass ratio (M_H2_/M_HI_), gas-to-dust mass ratio and SFE (=SFR/M_H2_) and study their dependences on pair type (S+S compared to S+E), stellar mass, and the presence of morphological interaction signs. We find an overall moderate enhancement (~2x) in both molecular gas fraction (M_H2_/M*) and molecular-to-atomic gas ratio (M_H2_/M_HI_) for star-forming galaxies in major-merger pairs compared to non-interacting comparison samples, whereas no enhancement was found for the SFE nor for the total gas mass fraction ((MHI+MH2)/M^Cstar). When divided into S+S and S+E, low mass and high mass, and with and without interaction signs, there is a small difference in SFE, a moderate difference in M_H2_/M*, and a strong difference in M_H2_/M_HI_ between subsamples. For the molecular-to-atomic gas ratio M_H2_/M_HI_, the difference between S+S and S+E subsamples is 0.55+/-0.18dex and between pairs with and without interaction signs is 0.65+/-0.16dex. Together, our results suggest that (1) star formation enhancement in close major-merger pairs occurs mainly in S+S pairs after the first close encounter (indicated by interaction signs)^Mbecause the HI gas is compressed into star-forming molecular gas by the tidal torque; and (2) this effect is much weakened in the S+E pairs.
- ID:
- ivo://CDS.VizieR/J/ApJS/178/302
- Title:
- C^18^O observations of multiple-core systems
- Short Name:
- J/ApJS/178/302
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of C^18^O observations by the Nobeyama Millimeter Array toward dense clumps with radii of ~0.3pc in six cluster-forming regions including massive (proto) stars. We identified 171 cores, whose radius, line width, and molecular mass range from 0.01 to 0.09pc, 0.43 to 3.33km/s, and 0.5 to 54.1M_{sun}_, respectively. Many cores with various line widths exist in one clump, and the index of the line width-radius relationship of the cores and the parental clump differs from core to core in the clump. This indicates that the degree of dissipation of the turbulent motion varies for each core in one clump.
- ID:
- ivo://CDS.VizieR/J/MNRAS/418/2121
- Title:
- CO 3-2 observations of outflows in W5
- Short Name:
- J/MNRAS/418/2121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- New James Clerk Maxwell Telescope (JCMT) HARP CO 3-2 observations of the W5 star forming complex are presented, totalling an area of ~12000-arcmin^2^ with sensitivity better than 0.1K per 0.4km/s channel. We discovered 55 CO outflow candidates, of which 40 are associated with W5 and 15 are more distant than the Perseus arm.
- ID:
- ivo://CDS.VizieR/J/A+A/554/A11
- Title:
- CO observations of polar ring galaxies
- Short Name:
- J/A+A/554/A11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have searched for CO lines in a sample of 21 new morphologically determined polar ring galaxies (of which 9 are kinematically confirmed), obtained from a wide search in the Galaxy Zoo project by Moiseev and collaborators. Polar ring galaxies (PRG) are a unique class of objects, tracing special episodes in the galaxy mass assembly: they could be formed through galaxy interaction, merging, but also through accretion from cosmic filaments. Beside, they enable the study of dark matter haloes in 3 dimensions. The polar ring itself is a sub-system rich in gas, where molecular gas is expected, and new stars are formed. Among the sample of 21 PRG, we have detected five CO-rich systems, that can now be followed up with higher spatial resolution. Their average molecular mass is 9.4x10^9^M_{sun}_, and their average gas fraction is 27% of their baryonic mass, with a range from 15 to 43%, implying that they just accreted a large amount of gas. The position of the detected objects in the velocity- magnitude diagram is offset from the Tully-Fisher relation of normal spirals, as was already found for PRG. This work is part of our multi-wavelength project to determine the detailed morphology and dynamics of Polar-Ring galaxies, test through numerical models their formation scenario, and deduce their dark matter content and 3D-shape.
- ID:
- ivo://CDS.VizieR/J/A+A/557/A104
- Title:
- CO observations of post-AGB stars
- Short Name:
- J/A+A/557/A104
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- There is a group of binary post-AGB stars that show conspicuous near infrared (NIR) excess, which is usually assumed to arise from hot dust in very compact possibly rotating disks. These stars are surrounded by significantly fainter nebulae than the standard, well studied protoplanetary and planetary nebulae (PPNe, PNe). We aim to identify and study extended rotating disks around these stars and shed light on the role of disks in the formation and shaping of planetary nebulae. We present high-sensitivity mm-wave observations of CO lines in 24 objects of this type. The resulting CO lines are compared with profiles expected to arise from rotating disks, from both theoretical and observational grounds. We derive simple formulae that allow us to determine the mass of the CO-emitting gas and estimate its extent. The reliability and uncertainty of the methods are also widely discussed. CO emission is detected in most observed sources, and the line profiles show that the emissions very probably come from disks in rotation. We derive typical values of the disk mass between 10^-3^ and 10^-2^M_{sun}_, about two orders of magnitude lower than the (total) masses of standard PPNe. The high-detection rate (upper limits being not very significant) clearly confirm that the NIR excess of these stars arises from compact disks in rotation, which are likely the inner parts of those found here. Low-velocity outflows are also found in about eight objects with moderate expansion velocities of ~10km/s, to be compared with the velocities of about 100km/s often found in standard PPNe. Except for two sources with complex profiles, the outflowing gas in our objects represents a minor nebular component. Our simple estimates of the typical disk sizes yields values ~0.5-1arcsec, which is between 5x10^15^ and 3x10^16^cm. Estimates of the linear momenta carried by the outflows, which can only be performed in a few well studied objects, also yield moderate values when compared to the linear momenta that can be released by the stellar radiation pressure (contrary, again, to the case of the very massive and fast bipolar outflows in $standard$ PPNe that are strongly overluminous). The mass and dynamics of nebulae around various classes of post-AGB stars differ very significantly, and we can expect the formation of PNe with very different properties.
- ID:
- ivo://CDS.VizieR/J/A+A/644/A64
- Title:
- CO observations of the IC443 SNR
- Short Name:
- J/A+A/644/A64
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Supernova remnants (SNRs) represent a major feedback source from stars in the interstellar medium of galaxies. During the latest stage of supernova explosions, shock waves produced by the initial blast modify the chemistry of gas and dust, inject kinetic energy into the surroundings, and may alter star formation characteristics. Simultaneously, gamma-ray emission is generated by the interaction between the ambient medium and cosmic rays (CRs), including those accelerated in the early stages of the explosion. We study the stellar and interstellar contents of IC443, an evolved shell-type SNR at a distance of 1.9kpc with an estimated age of 30kyr. We aim to measure the mass of the gas and characterize the nature of infrared point sources within the extended G region, which corresponds to the peak of gamma-ray emission detected by VERITAS and Fermi. We performed 10'x10' mapped observations of ^12^CO, ^13^CO J=1-0, J=2-1, and J=3-2 pure rotational lines, as well as C^18^O J=1-0 and J=2-1 obtained with the IRAM 30m and APEX telescopes over the extent of the gamma-ray peak to reveal the molecular structure of the region. We first compared our data with local thermodynamic equilibrium models. We estimated the optical depth of each line from the emission of the isotopologs ^13^CO and C^18^O. We used the population diagram and large velocity gradient assumption to measure the column density, mass, and kinetic temperature of the gas using ^12^CO and ^13^CO lines. We used complementary data (stars, gas, and dust at multiple wavelengths) and infrared point source catalogs to search for protostar candidates. Our observations reveal four molecular structures: a shocked molecular clump associated with emission lines extending between -31 and 16km/s, a quiescent, dark cloudlet associated with a line width of ~2km/s, a narrow ring-like structure associated with a line width of ~1.5km/s, and a shocked knot. We measured a total mass of ~230, ~90, ~210, and ~4M_{sun}_, respectively, for the cloudlet, ring-like structure, shocked clump, and shocked knot. We measured a mass of ~1100M_{sun}_ throughout the rest of the field of observations where an ambient cloud is detected. We found 144 protostar candidates in the region. Our results emphasize how the mass associated with the ring-like structure and the cloudlet cannot be overlooked when quantifying the interaction of CRs with the dense local medium. Additionally, the presence of numerous possible protostars in the region might represent a fresh source of CRs, which must also be taken into account in the interpretation of gamma-ray observations in this region.