- ID:
- ivo://CDS.VizieR/J/A+A/408/1029
- Title:
- Coordinates of Galactic planetary nebulae
- Short Name:
- J/A+A/408/1029
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The table is a compilation of the positions of 1312 Galactic Planetary Nebulae (PNe). We have used the 2nd generation of the Guide Star Catalogue (GSC-II, Cat. <I/271>) as a reference astrometric catalogue to compile the positions of 1086 Galactic Planetary Nebulae (PNe) listed in the Strasbourg ESO Catalogue (SEC, Cat. <V/84>), its supplement and the version 2000 of the Catalogue of Planetary Nebulae. This constitutes about 75% of all known PNe. For these PNe, the ones with a known central star (CS) or with a small diameter, we have derived coordinates with an absolute accuracy of ~0.35" in each coordinate, which is the intrinsic astrometric precision of the GSC-II. For another 226, mostly extended, objects without a GSC-II counterpart we give coordinates based on the second epoch Digital Sky Survey (DSS-II). While these coordinates may have systematic offsets relative to the GSC-II of up to 5 arcsecs, our new coordinates usually represent a significant improvement over the previous catalogue values for these large objects. This is the first truly homogeneous compilation of PNe positions over the whole sky and the most accurate one available so far.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/242/19
- Title:
- CO outflow candidates toward W3/4/5 complex
- Short Name:
- J/ApJS/242/19
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the Purple Mountain Observatory Delingha 13.7m telescope, we conducted a large-scale ^12^CO(J=1->0) outflow survey (over ~110deg^2^) toward the W3/4/5 complex and its surroundings. In total, 459 outflow candidates were identified. Approximately 62% (284) were located in the Perseus arm, including the W3/4/5 complex and its surroundings, while ~35% (162) were located in the Local arm, ~1% (5) were in the Outer arm, and ~2% (8) were in two interarm regions. This result indicated that star formation was concentrated in the Galactic spiral arms. The detailed spatial distribution of the outflow candidates showed that the Perseus arm presented the most active star formation among the study regions. The W3/4/5 complex is a great region to research massive star formation in a triggered environment. A key region, which has been well studied by other researches, is in the eastern high-density W3 complex that neighbors the W4 complex. Two shell-like structures in the Local arm contain candidates that can be used to study the impact on star formation imposed by massive or intermediate-mass stars in relatively isolated systems. The majority of outflow candidates in the two interarm regions and the Outer arm are located in filamentary structures.
- ID:
- ivo://CDS.VizieR/J/ApJS/251/26
- Title:
- CO outflow cand. toward W3/4/5 complex. II.
- Short Name:
- J/ApJS/251/26
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To date, few studies have focused on protostellar outflow feedback at scales larger than several parsecs. To address this paucity of research, we investigate the effects of feedback from CO outflow candidates on their parent clouds over ~110deg^2^ toward the W3/4/5 complex and its surroundings. Our search identified 265 ^13^CO clouds with radii being ~0.04-17.12pc. We estimate the turbulent support and potential disruptive effect of the outflow activities through analyzing physical properties of outflow candidates and their host clouds in terms of turbulence and gravitational binding energy. We find that (1) clouds of larger size might be less affected by feedback; (2) the possible scale break is >~4.7pc for both turbulent support and potential disruptive effect; (3) if outflows couple to dense gas where stars are forming, for clouds in the Perseus arm, a scale <~0.2-0.4pc is sufficient for the energy and momentum injected by outflow activity to maintain turbulence, while for clouds in the Local arm, the scale is <~0.1-0.2pc; and (4) for clouds in the Perseus arm, a scale <~0.3-1.0pc is needed for outflow activity to potentially disperse material away from the natal clouds, while for clouds in the Local arm, the scale is <~0.2-0.6pc. The strength of outflow activity may affect the values in points 3 and 4. Finally, we find that outflow feedback probably possesses the power to alter the line width-size relation.
- ID:
- ivo://CDS.VizieR/J/A+A/472/187
- Title:
- 12CO outflows towards submm cores in Perseus
- Short Name:
- J/A+A/472/187
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a search for outflows towards 51 submillimetre cores in Perseus. With consistently derived outflow properties from a large homogeneous dataset within one molecular cloud we can investigate further the mass dependence and time evolution of protostellar mass loss. Of the 51 cores, 37 show broad linewings indicative of molecular outflows. In 13 cases, the linewings could be due to confusion with neighbouring flows but 9 of those sources also have near-infrared detections confirming their protostellar nature. The total fraction of protostars in our sample is 65%. All but four outflow detections are confirmed as protostellar by Spitzer IR detections and only one Spitzer source has no outflow, showing that outflow maps at this sensitivity are equally good at identifying protostars as Spitzer. Outflow momentum flux correlates both with source luminosity and with core mass but there is considerable scatter even within this one cloud despite the homogeneous dataset. We fail to confirm the result of Bontemps et al. (1996A&A...311..858B) that Class I sources show lower momentum fluxes on average than Class 0 sources, with a KS test showing a significant probability that the momentum fluxes for both Class 0s and Class Is are drawn from the same distribution. We find that outflow power may not show a simple decline between the Class 0 to Class I stages. Our sample includes low momentum flux, low-luminosity Class 0 sources, possibly at a very early evolutionary stage. If the only mass loss from the core were due to outflows, cores would last for 10^5^-10^8^years, longer than current estimates of 1.5-4x10^5^years for the mean lifetime for the embedded phase. Additional mechanisms for removing mass from protostellar cores may be necessary.
- ID:
- ivo://CDS.VizieR/III/77
- Title:
- Copernicus 0.2-A Resolution Far-UV Stellar Spectra
- Short Name:
- III/77
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog is a subset comprising data for 60 O- and B-type stars observed by the Copernicus satellite. For each star a FITS file was created of the observed spectrum. Each spectrum has 2250 photometric data points. The wavelength range is from 1000 to 1450 Angstroems in 0.2-Angstrom steps. The data were acquired with photomultiplier U2, which had a nominal bandpass of 0.2 Angstrom (A) and scanned the spectrum with a 0.2 A step length, integrating for 13.6 sec at each wavelength position.
- ID:
- ivo://nasa.heasarc/xcopraw
- Title:
- Copernicus X-Ray Observations
- Short Name:
- Copern.X
- Date:
- 27 Sep 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- Copernicus was the third satellite in the OAO program. It was launched the 21 august of 1972 and operated till 1981. The main instrument was an ultraviolet telescope with a spectrometer to measure interstellar absorption lines in the spectra of stellar objects. However it carried also an X-ray experiment provided by University College of London/MSSL consisted in 4 co-aligned experiments sensitive in the 1-10 keV energy range. This database accesses the raw FITS file containing data obtained from the UCL X-ray Experiment (UCLXE) package on board Copernicus. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/J/A+A/585/A102
- Title:
- Copper abundances in solar neighborhood stars
- Short Name:
- J/A+A/585/A102
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Two distinct halo populations were found in the solar neighborhood by a series of works. They can be clearly separated by [{alpha}/Fe] and several other elemental abundance ratios including [Cu/Fe]. Very recently, a non-local thermodynamic equilibrium (non-LTE) study revealed that relatively large departures exist between LTE and non-LTE results in copper abundance analysis. The study also showed that non-LTE effects of neutral copper vary with stellar parameters and thus affect the [Cu/Fe] trend. We aim to derive the copper abundances for the stars from the sample of Nissen & Schuster (2010A&A...511L..10N) with both LTE and non-LTE calculations. Based on our results, we study the non-LTE effects of copper and investigate whether the high-{alpha} population can still be distinguished from the low-{alpha} population in the non-LTE [Cu/Fe] results. Our differential abundance ratios are derived from the high-resolution spectra collected from VLT/UVES and NOT/FIES spectrographs. Applying the MAFAGS opacity sampling atmospheric models and spectrum synthesis method, we derive the non-LTE copper abundances based on the new atomic model with current atomic data obtained from both laboratory and theoretical calculations. The copper abundances determined from non-LTE calculations are increased by 0.01 to 0.2dex depending on the stellar parameters compared with the LTE results. The non-LTE [Cu/Fe] trend is much flatter than the LTE one in the metallicity range -1.6<[Fe/H]<-0.8. Taking non-LTE effects into consideration, the high- and low-{alpha} stars still show distinguishable copper abundances, which appear even more clear in a diagram of non-LTE [Cu/Fe] versus [Fe/H]. The non-LTE effects are strong for copper, especially in metal-poor stars. Our results confirmed that there are two distinct halo populations in the solar neighborhood. The dichotomy in copper abundance is a peculiar feature of each population, suggesting that they formed in different environments and evolved obeying diverse scenarios.
- ID:
- ivo://CDS.VizieR/J/A+A/607/A110
- Title:
- CO properties of compact group galaxies
- Short Name:
- J/A+A/607/A110
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Compact groups (CGs) provide an environment in which interactions between galaxies and with the intra-group medium enable and accelerate galaxy transitions from actively star forming to quiescent. Galaxies in transition from active to quiescent can be selected, by their infrared (IR) colors, as canyon or infrared transition zone (IRTZ) galaxies. We used a sample of CG galaxies with IR data from the Wide Field Infrared Survey Explorer (WISE) allowing us to calculate the stellar mass and star formation rate (SFR) for each galaxy. Furthermore, we present new CO(1-0) data for 27 galaxies and collect data from the literature to calculate the molecular gas mass for a total sample of 130 galaxies. This data set allows us to study the difference in the molecular gas fraction (Mmol/Mstar) and star formation efficiency (SFE=SFR/Mmol) between active, quiescent, and transitioning (i.e., canyon and IRTZ) galaxies. We find that transitioning galaxies have a mean molecular gas fraction and a mean SFE that are significantly lower than those of actively star-forming galaxies. The molecular gas fraction is higher than that of quiescent galaxies, whereas the SFE is similar. These results indicate that the transition from actively star-forming to quiescent in CG galaxies goes along with a loss of molecular gas, possibly due to tidal forces exerted from the neighboring galaxies or a decrease in the gas density. In addition, the remaining molecular gas loses its ability to form stars efficiently, possibly owing to turbulence perturbing the gas, as seen in other, well-studied examples such as Stephan's Quintet and HCG 57. Thus, the amount and properties of molecular gas play a crucial role in the environmentally driven transition of galaxies from actively star forming to quiescent.
- ID:
- ivo://CDS.VizieR/VII/50
- Title:
- CO Radial Velocities Toward Galactic H II Regions
- Short Name:
- VII/50
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The catalog contains machine-readable versions of the "Catalog of CO Radial Velocities Toward Galactic HII Regions" (Blitz et al. 1982) and the "Catalog of Carbon Monoxide Observations of Southern Hemisphere HII Regions" (Gillespie et al. 1977) in two separate files. The former is a catalog of 242 molecular cloud complexes that are associated with optical HII regions and includes source names, coordinates, CO radial velocities, antenna temperatures and full width at half-maximum at the position of the strongest CO emission, references for the observations, distances to the stars exciting the HII regions, and optical diameters of the HII regions. The latter is the first CO survey of the southern sky; it was made using the Anglo-Australian 3.9-m optical telescope at 115GHz (2.6-mm wavelength) with a hot-electron bolometer receiver located at the Coude focus. The data were collected during two observing periods (September 1975, April 1976) and include designations, coordinates, median values for the velocities, and distances to the stars exciting the HII regions.
- ID:
- ivo://CDS.VizieR/J/A+A/521/A39
- Title:
- Cordoba Carte du Ciel-Astrographic Catalog, CCAC
- Short Name:
- J/A+A/521/A39
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on stellar positions and proper motions, we aim to re-analyse the region of the controversial open cluster Collinder 132. Methods. We have developed a model which analyse the proper motion distribution and the stellar density to find moving groups. The astrometric data was obtained from four Carte du Ciel (CdC) and one Astrogaphic Catalogue (AC) plates of the Cordoba Astronomical Observatory collection (Argentina). We detected an open cluster from the field stars and calculated the mean proper motion and the membership probabilities of the stars of the region. We report new coordinates of its centre RAc=108.347deg, DEc=-31.011deg, the components of mean proper motion mu_RA_cosDE=-2.62+/-0.44mas/yr, mu_DE_=4.79+/-0.88mas/yr. 11 stars are astrometric members giving a value of 370 for the cluster angular diameter. 6 stars fullfill astrometric and photometric analysis for being cluster members and locate the cluster at 360pc from the Sun. An over-density in the VPD was found after removing the cluster members, consequently a simple model for the proper motion distribution of an association and of the field was adopted. We report the components of the association mean proper motion mu_RA_cosDE=-1.38+/-0.14mas/yr, mu_DE_=2.26+/-0.16mas/yr. 174 astrometric members were found while 11 members have been located between 417 and 660pc from the Sun by Tycho-2 photometry.