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- ID:
- ivo://CDS.VizieR/J/A+A/552/A12
- Title:
- Abundances of PNe in NGC 300
- Short Name:
- J/A+A/552/A12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained deep spectroscopy of 26 planetary nebulae (PNe) and 9 compact HII regions in the nearby spiral galaxy NGC 300, and analyzed them together with the giant HII regions observed by Bresolin et al. (2009ApJ...700..309B). We have determined the physical properties of all those objects and their content in He, N, O, Ne, S and Ar in a consistent way. We find that compact HII regions have abundances similar to those of giant HII regions, while PNe have systematically larger N/O ratios and similar Ne/O and Ar/O ratios. We demonstrate that this nitrogen enhancement in PNe cannot be due to second dredge-up in the progenitor stars, since their initial masses are around 2-2.5M_{sun}_. An extra mixing process is required, perhaps be driven by rotation. Concerning the radial abundance distribution, PNe behave differently from HII regions: In the central parts, they show an average O/H smaller by 0.15dex. Their abundance dispersion at any galactocentric radius is significantly larger than for HII regions and many of them have O/H values higher than HII regions at the same galactocentric distance, suggesting that oxygen production in the PN progenitors in NGC 300 is common. PN abundance gradients in O/H, Ne/H and Ar/He are significantly shallower than those of HII regions. We argue that this indicates a steepening of the metallicity gradient in NGC 300 during the last Gr, rather than the effect of radial stellar motions.
- ID:
- ivo://CDS.VizieR/J/A+A/380/300
- Title:
- Abundances of PN towards Galactic bulge
- Short Name:
- J/A+A/380/300
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this work we report spectrophotometric observations of a planetary nebula sample towards the galactic bulge. A total of 45 PNe was observed and their physical parameters (electron density and temperature) were derived. Ionic abundances were calculated using a three-level atom model and abundances were derived through ionisation correction factors. Results show low abundance objects at high galactic latitudes, indicating a possible vertical gradient inside the bulge. A few objects with low N/O ratio were found, which could have originated from old, low mass progenitors.
- ID:
- ivo://CDS.VizieR/J/ApJ/723/658
- Title:
- Abundances of the halo PN BoBn 1
- Short Name:
- J/ApJ/723/658
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have performed a comprehensive chemical abundance analysis of the extremely metal-poor ([Ar/H]<-2) halo planetary nebula (PN) BoBn 1 based on International Ultraviolet Explorer archive data, Subaru/High-Dispersion Spectrograph spectra, VLT/UVES archive data, and Spitzer/IRS spectra. We have detected over 600 lines in total and calculated ionic and elemental abundances of 13 elements using detected optical recombination lines (ORLs) and collisionally excited lines (CELs). The estimations of C, N, O, and Ne abundances from the ORLs and Kr, Xe, and Ba from the CELs are done the first for this nebula, empirically and theoretically. We have detected five fluorine and several slow neutron capture elements (the s-process). The amounts of [F/H], [Kr/H], and [Xe/H] suggest that BoBn 1 is the most F-rich among F-detected PNe and is a heavy s-process element rich PN. We have confirmed dust in the nebula that is composed of amorphous carbon and polycyclic aromatic hydrocarbons with a total mass of 5.8x10^-6^M_{sun}_. The photoionization models built with non-LTE theoretical stellar atmospheres indicate that the progenitor was a 1-1.5M_{sun}_ star that would evolve into a white dwarf with an ~0.62M_{sun}_ core mass and ~0.09M_{sun}_ ionized nebula. We have measured a heliocentric radial velocity of +191.6+/-1.3km/s and expansion velocity 2V_exp_ of 40.5+/-3.3km/s from an average over 300 lines.
- ID:
- ivo://CDS.VizieR/J/AN/323/484
- Title:
- Accurate coordinates of Planetary Nebulae
- Short Name:
- J/AN/323/484
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accurate optical coordinates of 734 PNe, measured on the charts of the Digitized Palomar Sky Survey (DSS-2), are presented. As a result of the discussion about the external accuracy the constants -0.8" in RA and +0.8" in DEC should be added to the coordinates measured by us. They were used but rounded off already in CGPN(2000).
- ID:
- ivo://CDS.VizieR/J/ApJS/91/347
- Title:
- A 5-GHz VLA Survey of the Galactic Plane
- Short Name:
- J/ApJS/91/347
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have used the VLA to survey the inner Galaxy (|b|<0.4{deg}, l=350-40{deg}) at 5GHz to a limiting sensitivity of between 2.5 and 10mJy. The survey has resulted in a catalog of 1272 discrete sources (including 100 sources outside the formal survey area) of which we have tentatively identified ~450 as ultracompact H II regions and ~45 as planetary nebulae. Approximately 30% of the radio sources are detected in the IRAS Point Source Catalog. The results confirm a scale height of only 30pc for ultracompact H II regions. We show that source lists generated from the IRAS Point Source Catalog alone suffer serious effects; the combination of the IRAS and radio surveys allows us to produce a much more complete census of the regions of massive star formation in our Galaxy.
- ID:
- ivo://jvo/isas/darts/akari/AKARI-IRC_Spectrum_Pointed_GALPN_1.0
- Title:
- AKARI/IRC NIR Spectral Atlas of Galactic Planetary Nebulae
- Short Name:
- AKARI_IRC_SPEC_GALPN
- Date:
- 29 May 2024 05:26:27
- Publisher:
- JVO
- Description:
- This catalog contains near-infrared (2.5--5.0 micron) low-resolution (R ~ 100) spectra of 72 Galactic Planetary Nebulae (PNe), obtained with the InfraRed Camera (IRC) onboard the AKARI satellite in the post-helium phase. The objects were treated as almost point sources for the IRC. Grism spectroscopy was carried out in the 1-arcmin window. The near-infrared spectra were obtained in a slit-less mode without any flux loss due to a slit. The spectra show emission features including hydrogen recombination lines, helium recombination lines, the 3.3--3.5 micron hydrocarbon features, [MgIV] at 4.49 micron, and [ArVI] at 4.53 micron. This catalog also contains the intensity and equivalent width of these emission features measured by spectral fitting. The source list (source.dat) summarizes observations. As ancillary data, the magnitudes in the V- and Ks-band, the extinction at V-band toward the objects, and the effective temperature collected from literature are listed in another table (misc.dat). The intensities and the equivalent widths of the emission features are tabulated in different tables (intens.dat and equivw.dat). Each object is identified by the PNG ID (PNG) or an observation ID (Obs-ID). One-dimensional near-infrared spectra are stored in a directory (spc/). Each spectrum is identified by the observation ID.
- ID:
- ivo://jvo/isas/darts/akari/ObsTAP
- Title:
- AKARI ObsTAP service
- Short Name:
- AKARI_OBSTAP
- Date:
- 29 May 2024 05:06:13
- Publisher:
- JVO
- Description:
- This is an ObsTAP service for AKARI data.
- ID:
- ivo://CDS.VizieR/J/ApJ/711/619
- Title:
- {alpha}-element abundances in galactic PNe
- Short Name:
- J/ApJ/711/619
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present emission line strengths, abundances, and element ratios (X/O for Ne, S, Cl, and Ar) for a sample of 38 Galactic disk planetary nebulae (PNe) consisting primarily of Peimbert classification Type I. Spectrophotometry for these PNe incorporates an extended optical/near-IR range of 3600-9600{AA} including the [SIII] lines at 9069{AA} and 9532{AA}, setting this relatively large sample apart from typical spectral coverage. We have utilized Emission Line Spectrum Analyzer, a five-level atom abundance routine, to determine Te, Ne, ionization correction factors, and total element abundances, thereby continuing our work toward a uniformly processed set of data. With a compilation of data from >120 Milky Way PNe, we present results from our most recent analysis of abundance patterns in Galactic disk PNe. With a wide range of metallicities, galactocentric distances, and both Type I and non-Type I objects, we have examined the alpha elements against HII regions and blue compact galaxies (H2BCGs) to discern signatures of depletion or enhancement in PNe progenitor stars, particularly the destruction or production of O and Ne.
- ID:
- ivo://CDS.VizieR/J/AJ/142/139
- Title:
- A new catalog of HII regions in M31
- Short Name:
- J/AJ/142/139
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new catalog of HII regions in M31. The full disk of the galaxy (~24kpc from the galaxy center) is covered in a 2.2deg^2^ mosaic of 10 fields observed with the Mosaic Camera on the Mayall 4m telescope as part of the Local Group Galaxies survey.
