- ID:
- ivo://CDS.VizieR/J/ApJS/160/272
- Title:
- A CO survey of young planetary nebulae
- Short Name:
- J/ApJS/160/272
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of a sensitive survey of young planetary nebulae in the CO J=2-1 line that significantly increases the available data on warm, dense, molecular gas in the early phases of planetary nebula formation. The observations were made using the IRAM 30m telescope with the 3x3 pixel Heterodyne Receiver Array (HERA). The array provides an effective means of discriminating the CO emission of planetary nebulae in the Galactic plane from contaminating emission of interstellar clouds along the line of sight. A total of 110 planetary nebulae were observed in the survey, and 40 were detected. The results increase the number of young planetary nebulae with known CO emission by approximately a factor of 2. The CO spectra yield radial velocities for the detected nebulae, about half of which have uncertain or no velocity measurements at optical wavelengths. The CO profiles range from parabolic to double-peaked, tracing the evolution of structure in the molecular gas. The line widths are significantly larger than on the asymptotic giant branch, and many of the lines show extended wings, which probably result from the effects on the envelopes of high-velocity jets.
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- ID:
- ivo://CDS.VizieR/J/AJ/117/446
- Title:
- AFGL 5157 near-IR imaging
- Short Name:
- J/AJ/117/446
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present near-infrared images of the star-forming region AFGL 5157 in the JHK broadband filters and H_2_v=1-0S(1) narrowband filter. The images reveal a dense cluster of stars and infrared nebulosities associated with previously known infrared sources. Of 54 near-infrared sources detected in the nebula, NGC 1985, 12 exhibit infrared excesses typical of T Tauri stars, Herbig Ae/Be stars, and protostars. The magnitude and color distribution of the cluster of stars in the nebula are found to be different from those outside the nebular region. The K'-magnitude distribution of the cluster is quite flat, while the noncluster is peaked toward the low magnitude. The [H-K'] color of the cluster also displays 0.3 mag redder than that of the noncluster. The infrared nebula displays a bright nucleus with two spirals extended to the north and south. In light of the color properties of the nebula, we propose a shell model for the nebular structure that could be formed by star-forming activity of the central cluster.
- ID:
- ivo://CDS.VizieR/J/A+A/618/A164
- Title:
- ALMA viewing of OH 231.8+4.2
- Short Name:
- J/A+A/618/A164
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present continuum and molecular line emission ALMA observations of OH 231.8+4.2, a well studied bipolar nebula around an asymptotic giant branch (AGB) star. The high angular resolution (~0.2"-0.3") and sensitivity of our ALMA maps provide the most detailed and accurate description of the overall nebular structure and kinematics of this object to date. We have identified a number of outflow components previously unknown. Species studied in this work include ^12^CO, ^13^CO, CS, SO, SO_2_, OCS, SiO, SiS, H_3_O^+^, Na^37^Cl, and CH_3_OH. The molecules Na^37^Cl and CH_3_OH are first detections in OH 231.8+4.2, with CH_3_OH being also a first detection in an AGB star.
- ID:
- ivo://CDS.VizieR/J/A+A/564/A21
- Title:
- Ammonia observations in G79.29+0.46
- Short Name:
- J/A+A/564/A21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of observations of the ammonia (1,1) and (2,2) lines in a field of 7'x7' centered in the LBV ring nebula G79.29+0.46. The survey also includes a significant part of the IRDC G79.3+0.3. Data have been gathered with the 100m radio telescope at Effelsberg. Both lines have been observed simultaneously with excellent spectral resolution. A clump of the IRDC, referred in the paper as the SW region, is sampled every 20"; sampling is 40" elsewhere.
- ID:
- ivo://CDS.VizieR/J/MNRAS/452/3969
- Title:
- ATCA Survey of Sagittarius B2 at 7mm
- Short Name:
- J/MNRAS/452/3969
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 30-50GHz survey of Sagittarius B2(N) conducted with the Australia Telescope Compact Array (ATCA) with 5 - 10 arcsec resolution. We analyze the spectra towards three HII regions that have foreground molecular gas in Sgr B2. Towards the most line-dense region, we detect >500 spectral line components, >90% of which are assigned to H and He recombination lines and 53 firmly identified molecular species (not including isotopologues). The data reveal extremely subthermally excited molecular gas in Sgr B2 absorbing against the continuum background, as well as molecular line emission from two hot cores in Sgr B2(N). They also also contain line-of-sight absorption by ~15 molecules observed in translucent gas in the Galactic Center, bar, and intervening spiral arm clouds, revealing the complex chemistry and clumpy structure of this gas. Formamide (NH_2_CHO) is detected for the first time in a translucent cloud.
- ID:
- ivo://CDS.VizieR/VII/220A
- Title:
- Barnard's Catalogue of 349 Dark Objects in the Sky
- Short Name:
- VII/220A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This catalogue was created based on the original published catalogue by Barnard E.E., 1927, Carnegie Institution of Washington, "A photographic Atlas of selected regions of the Milky Way". The catalogue contains positions of 349 Barnard Objects. The objects with numbers from 1 to 175 are classified in the first Barnard catalogue (1919ApJ....49....1B); three of the objects in that list have been omitted here (Nos 52, 131a, and 172) because these objects had been listed twice. The objects from Barnard's second list are numbered from 201 to 370 -- there are therefore no objects having the numbers from 176 to 200. Their positions were determined by Miss Calvert. The epoch for all positions in the original published catalogue was 1875.0. Positions for both 1875.0 and 2000.0, the diameters and the notes are included in this machine-readable catalogue.
- ID:
- ivo://CDS.VizieR/J/A+AS/126/73
- Title:
- BVRI photometry in dark globules
- Short Name:
- J/A+AS/126/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using a CCD detector, BVRI photometry has been carried out in the vicinity of nine Lynds dark nebulae. In conjunction with spectroscopic data which could be obtained at a later stage, the data listed herein could be used for possible distance determinations of the nine nebulae.
- ID:
- ivo://CDS.VizieR/J/ApJS/194/5
- Title:
- Carina OB stars in the CCCP catalog
- Short Name:
- J/ApJS/194/5
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Chandra Carina Complex contains 200 known O- and B-type stars. The Chandra survey detected 68 of the 70 O stars and 61 of 127 known B0-B3 stars. We have assembled a publicly available optical/X-ray database to identify OB stars that depart from the canonical L_X/L_bol relation or whose average X-ray temperatures exceed 1keV. Among the single O stars with high kT we identify two candidate magnetically confined wind shock sources: Tr16-22, O8.5 V, and LS 1865, O8.5 V((f)). The O4 III(fc) star HD 93250 exhibits strong, hard, variable X-rays, suggesting that it may be a massive binary with a period of >30d. The visual O2 If* binary HD 93129A shows soft 0.6keV and hard 1.9keV emission components, suggesting embedded wind shocks close to the O2 If* Aa primary and colliding wind shocks between Aa and Ab. Of the 11 known O-type spectroscopic binaries, the long orbital-period systems HD 93343, HD 93403, and QZ Car have higher shock temperatures than short-period systems such as HD 93205 and FO 15. Although the X-rays from most B stars may be produced in the coronae of unseen, low-mass pre-main-sequence companions, a dozen B stars with high L_X_ cannot be explained by a distribution of unseen companions. One of these, SS73 24 in the Treasure Chest cluster, is a new candidate Herbig Be star.
- ID:
- ivo://CDS.VizieR/VII/231
- Title:
- Catalog of bright diffuse Galactic nebulae
- Short Name:
- VII/231
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Catalog of bright diffuse Galactic nebulae was compiled in the frame of a thesis investigating the spatial distribution and the geometrical properties of bright diffuse Galactic nebulae, together with some inquiries into the interstellar absorption problem. It is a mostly complete compilation of the knowledge about bright galactic nebulae around 1945. Global parameters derived for each nebula include a classification, the apparent dimensions, and distance estimations; the Catalog includes also extensive notes, and its bibliography covers the period 1877 to 1941.
- ID:
- ivo://CDS.VizieR/J/ApJS/175/522
- Title:
- Catalog of PNe in NGC 4697
- Short Name:
- J/ApJS/175/522
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 535 planetary nebulae (PNs) discovered in the flattened elliptical galaxy NGC 4697, using the FORS1 Cassegrain spectrograph of the Very Large Telescope of the European Southern Observatory at Cerro Paranal, Chile. The catalog provides positions [(x,y)-coordinates relative to the center of light of NGC 4697, as well as {alpha},{delta}] and, for almost all PNs, the magnitude m(5007) and the heliocentric radial velocity in km/s.
