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- ID:
- ivo://CDS.VizieR/J/ApJ/616/804
- Title:
- Planetary Nebula Kinematics in M31
- Short Name:
- J/ApJ/616/804
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present kinematics of 135 planetary nebulae (PNs) in M31 from a survey covering 3.9{deg}^2^ and extending out to 15kpc from the southwest major axis and more than 20kpc along the minor axis. The majority of our sample, even well outside the disk, shows significant rotational support (mean line-of-sight velocity 116km/s).
- ID:
- ivo://CDS.VizieR/J/A+A/634/A47
- Title:
- Planetary nebula NGC3132 MUSE images
- Short Name:
- J/A+A/634/A47
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Two-dimensional spectroscopic data for the whole extent of the NGC3132 planetary nebula have been obtained. We deliver a reduced data-cube and high-quality maps on a spaxel-by-spaxel basis for the many emission lines falling within the Multi-Unit Spectroscopic Explorer (MUSE) spectral coverage over a range in surface brightness >1000. Physical diagnostics derived from the emission line images, opening up a variety of scientific applications, are discussed. Data were obtained during MUSE commissioning on the European Southern Observatory (ESO) Very Large Telescope and reduced with the standard ESO pipeline. Emission lines were fitted by Gaussian profiles. The dust extinction, electron densities, and temperatures of the ionised gas and abundances were determined using Python and PyNeb routines. The delivered datacube has a spatial size of ~63"x123", corresponding to ~0.26x0.51pc^2^ for the adopted distance, and a contiguous wavelength coverage of 4750-9300{AA} at a spectral sampling of 1.25{AA}/pix. The nebula presents a complex reddening structure with high values (c(H{beta})~0.4) at the rim. Density maps are compatible with an inner high-ionisation plasma at moderate high density (~1000cm^-3^), while the low-ionisation plasma presents a structure in density peaking at the rim with values ~700cm^-3^. Median Te, using different diagnostics, decreases according to the sequence [NII],[SII]->[SIII]->[OI]->HeI->Paschen Jump. Likewise, the range of temperatures covered by recombination lines is much larger than those obtained from collisionally excited lines (CELs), with large spatial variations within the nebula. If these differences were due to the existence of high density clumps, as previously suggested, these spatial variations would suggest changes in the properties and/or distribution of the clumps within the nebula. We determined a median helium abundance He/H=0.124, with slightly higher values at the rim and outer shell. The range of measured ionic abundances for light elements are compatible with literature values. Our kinematic analysis nicely illustrates the power of 2D kinematic information in many emission lines, which sheds light on the intrinsic structure of the nebula. Specifically, our derived velocity maps support a geometry for the nebula that is similar to the diabolo-like model previously proposed, but oriented with its major axis roughly at P.A.~22{deg}. We identified two low-surface brightness arc-like structures towards the northern and southern tips of the nebula, with high extinction, high helium abundance, and strong low-ionisation emission lines. They are spatially coincident with some extended low-surface brightness mid-infrared emission. The characteristics of the features suggest that they could be the consequence of precessing jets caused by the binary star system. A simple 1D Cloudy model is able to reproduce the strong lines in the integrated spectrum of the whole nebula with an accuracy of 15% . Together with similar work with MUSE on NGC7009, the present study illustrates the enormous potential of wide field integral field spectrographs for the study of Galactic PNe.
- ID:
- ivo://CDS.VizieR/J/ApJ/414/463
- Title:
- Planetary nebula system of NGC 5128
- Short Name:
- J/ApJ/414/463
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the result of a planetary nebula (PN) survey of the nearby giant elliptical galaxy NGC 5128 performed with CCD cameras at the prime focus of the CTIO 4m in telescope. By comparing CCD images centered on the characteristic emission line [O III] {lambda}5007{AA} and on the adjacent continuum, we identify a total of 785 PNs in areas extending 20kpc along the photometric major axis and covering the whole galaxy to 10kpc. From these data, we form a complete sample of 224 PN's extending to a dereddened limiting magnitude of m_5007_=24.8, which extends 1.5mag down the PN luminosity function (PNLF). Adopting a foreground extinction of E(B-V)=0.1, we derive a distance to the galaxy of 3.5+/-0.2Mpc, in excellent agreement with the surface brightness fluctuation method. No population effect on the bright cutoff of PNLF is observed in the isophotal radius range of 2-16kpc, but the luminosity specific PN density ({alpha}_2.5_) seems to increase with radius inside of 7kpc, in agreement with the {alpha}_2.5_-color relation observed for other galaxies.
205. PN abundances
- ID:
- ivo://CDS.VizieR/J/A+AS/126/297
- Title:
- PN abundances
- Short Name:
- J/A+AS/126/297
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Abundance determinations of about 110 planetary nebulae, which are likely to be in the Galactic Bulge are presented. Plasma diagnostics have been performed by making use of the available forbidden line ratios combined with radio continuum measurements. Chemical abundances of He, O, N, Ne, S, Ar, and Cl are then derived by employing theoretical nebular models as interpolation devices in establishing the ionization correction factors (ICFs) used to estimate the distribution of atoms among unobserved ionization stages. The overall agreement between the results derived by using the model-ICFs and those obtained from the theoretical models is reasonably good. The uncertainties related to the total abundances show a clear dependence on the level of excitation. In most cases, the abundances of chlorine can be derived only in objects with a relatively high Cl-abundance. Contrary to the conclusion previously drawn by Webster (1988MNRAS.230..377W), we found the excitation classes are not uniformly distributed. A clear peak at about classes 5 and 6 is noticed. The distribution is shifted toward a lower excitation range with respect to that of the nearby nebulae, reflecting the difference in the central star temperature distribution between the two samples.
- ID:
- ivo://CDS.VizieR/J/A+A/336/667
- Title:
- PN abundances in five galaxies
- Short Name:
- J/A+A/336/667
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have collected photometric and spectroscopic data on planetary nebulae (PNe) in 5 galaxies: the Milky Way (bulge), M31 (bulge), M 32, the LMC and the SMC. We have computed the abundances of O, Ne and N and compared them from one galaxy to another. In each Galaxy, the distribution of oxygen abundances has a large dispersion. The average O/H ratio is larger in the M31 and the Galactic bulge PNe than in those in the Magellanic Clouds. In a given galaxy, it is also larger for PNe with [OIII] luminosities greater than 100L_{sun}_, which are likely to probe more recent epochs in the galaxy history. We find that the M31 and the Galactic bulge PNe extend the very tight Ne/H-O/H correlation observed in the Galactic disk and Magellanic Clouds PNe towards higher metallicities. We note that the anticorrelation between N/O and O/H that was known to occur in the Magellanic Clouds and in the disk PNe is also marginally found in the PNe of the Galactic bulge. Furthermore, we find that high N/O ratios are higher for less luminous PNe. In M 32, all PNe have a large N/O ratio, indicating that the stellar nitrogen abundance is enhanced in this galaxy. We have also compared the PN evolution in the different galactic systems by constructing diagrams that are independent of abundances, and have found strikingly different behaviours of the various samples. In order to help in the interpretation of these data, we have constructed a grid of expanding, PN photoionization models in which the central stars evolve according to the evolutionary tracks of Bloecker (1995A&A...299..755B). These models show that the apparent spectroscopic properties of PNe are extremely dependent, not only on the central stars, but also on the masses and expansion velocities of the nebular envelopes. The main conclusion of the confrontation of the observed samples with the model grids is that the PN populations are indeed not the same in the various parent galaxies. Both stars and nebulae are different. In particular, the central stars of the Magellanic Clouds PNe are shown to evolve differently from the hydrogen burning stellar evolutionary models of Bloecker (1995). In the Galactic bulge, on the other hand, the behaviour of the observed PNe is roughly compatible with the theoretical stellar evolutionary tracks. The case of M31 is not quite clear, and additional observations are necessary. It seems that the central star mass distribution is narrower for the M31 PNe than for the Galactic bulge PNe. We show that spectroscopy of complete samples of PNe down to a factor 100 below the maximum luminosity would help to better characterize the PN central star mass distribution.
- ID:
- ivo://CDS.VizieR/J/A+A/495/447
- Title:
- PN and HII regions in NGC6822
- Short Name:
- J/A+A/495/447
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Images obtained with the CTIO 4-m telescope and the MOSAIC-2 wide field camera in [OIII] 5007 and Halpha on-band and off-band filters are analyzed to search for emission line objects in the dwarf galaxy NGC 6822. In particular we search for planetary nebula (PN) candidates. In addition, imaging and spectroscopy of a sub-sample of objects obtained with the ESO VLT and FORS 2 spectrograph are used to calibrate the MOSAIC imaging. In the continuum-subtracted images, a large number of line emission regions were detected, for which we measured instrumental magnitudes in all the filters. The [OIII] 5007 and Halpha+[NII] magnitudes were calibrated with the spectroscopy.
- ID:
- ivo://CDS.VizieR/J/A+A/466/75
- Title:
- PN and HII regions of West and East of NGC 3109
- Short Name:
- J/A+A/466/75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Images obtained with the ESO VLT and FORS1 in [O III] 5007 on- and off-band, as well as r_Gunn filters, are analyzed to search for planetary nebula (PN) candidates. In the continuum-subtracted [O III] 5007 on-band images, a large number of emission-line regions were detected. We describe the criteria employed for distinguishing PN candidates from compact HII regions.
209. PN distance scale
- ID:
- ivo://CDS.VizieR/J/A+AS/108/485
- Title:
- PN distance scale
- Short Name:
- J/A+AS/108/485
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/A+A/306/9
- Title:
- PNe and HII in NGC 300
- Short Name:
- J/A+A/306/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report a search for planetary nebulae and H II regions in the central part of the late-type spiral NGC 300, using a CCD and the on-band/off-band filter technique. The total exposure time for all frames was 4 hours. We have identified 34 PNs and 88 H II regions. We construct the cumulative [O III] {lambda}5007 PN luminosity function (PNLF) and obtain a distance modulus of 26.9+/-0.4, in satisfactory agreement with the Cepheid distance modulus (26.7+/-0.1). We make a general comparison between Cepheid and PNLF distances, showing that they are in excellent overall agreement. NGC 300 is in principle one of the best possible calibrators of the PNLF method of distance determination, to be preferentially applied, like the LMC, in cases of populations with recent star formation (as opposed to the bulge of M 31, which has served as calibrator for populations without recent star formation).
