Planetary nebulae in local group galaxies. IV - Identifications, positions, and radial velocities of nebulae in NGC 147 and NGC 185

1977 ◽  
Vol 213 ◽  
pp. 18 ◽  
Author(s):  
H. C. Ford ◽  
G. Jacoby ◽  
D. C. Jenner
Keyword(s):  
Local Group ◽  
Planetary Nebulae ◽  
Radial Velocities

scholarly journals Planetary Nebulae in Galaxies Beyond the Local Group

1989 ◽  
Vol 131 ◽  
pp. 335-350 ◽  
Author(s):  
H. C. Ford ◽  
R. Ciardullo ◽  
G. H. Jacoby ◽  
X. Hui
Keyword(s):  
Velocity Dispersion ◽  
Local Group ◽  
Strong Support ◽  
Stellar Dynamics ◽  
Planetary Nebulae ◽  
Central Star ◽  
Radial Velocities ◽  
Luminosity Functions ◽  
Standard Candle ◽  
Small Dispersion

Planetary nebulae can be used to estimate the distances to galaxies and to measure stellar dynamics in faint halos. We discuss surveys which have netted a total of 665 candidate planetary nebulae in NGC 5128 (Cen A), NGC 5102, NGC 3031 (M81), NGC 3115, three galaxies in the Leo Group (NGC 3379, NGC 3384, NGC 3377), NGC 5866, and finally, in NGC 4486 (M87). Radial velocities of planetaries in M32 have shown that its halo velocity dispersion is most likely isotropic. Radial velocities of planetaries in M31 show that ∼ 2/3 of the nebulae with projected radii between 15 and 30 kpc are members of a rotating thick disk with slight asymmetric drift, while ∼ 1/3 belong to a slowly rotating halo. Velocities of 116 nebulae in NGC 5128 reveal pronounced rotation and a slowly declining velocity dispersion in the halo out to 20 kpc. The [O III] λ5007 luminosity functions (PNLFs) in NGC 5128, M81, and the three Leo Galaxies have the same shape over the first magnitude. The highly consistent distances derived from the brightnesses of the jth nebula and the median nebula in different fields in the same galaxy and from different galaxies in the same group lend strong support to the suggestion that planetaries are an accurate standard candle in old stellar populations. Comparison of theoretical luminosity functions to the observed PNLFs shows that there is a very small dispersion in the central star masses.

scholarly journals A consolidated online database of Galactic planetary nebulae

2011 ◽  
Vol 7 (S283) ◽  
pp. 442-443
Author(s):  
Brent Miszalski ◽  
A. Acker ◽  
F. Ochsenbein ◽  
Q. A. Parker
Keyword(s):  
Planetary Nebulae ◽  
Central Star ◽  
Radial Velocities ◽  
Online Database ◽  
Line Intensities ◽  
Multi Wavelength

AbstractSince the issue of the unifying Strasbourg-ESO Catalogue of Galactic Planetary Nebulae (SECGPN) a large number of new discoveries have been made thanks to improved surveys and discovery techniques. The increasingly heterogeneous published population of Galactic PNe, that we have determined totals <2850 PNe, is becoming more difficult to study on the whole without a centralised repository. We introduce a consolidated and interactive online database with object classifications that reflect the latest multi-wavelength data and the most recent results. The extensible database, hosted by the Centre de Donnees astronomique de Strasbourg (CDS), will contain a wealth of observed data for large, well-defined samples of PNe including coordinates, multi-wavelength images, spectroscopy, line intensities, radial velocities and central star information. It is anticipated that the database will be publicly released early 2012.

scholarly journals Planetary Nebulae in Local Group Galaxies

1983 ◽  
Vol 103 ◽  
pp. 443-460
Author(s):  
Holland C. Ford
Keyword(s):  
Local Group ◽  
Planetary Nebulae ◽  
Stellar Populations ◽  
Chemical Compositions ◽  
H Ii Regions ◽  
Helium Abundance ◽  
Abundance Gradient ◽  
Star Forming ◽  
Ic 10 ◽  
Ngc 6822

Recent surveys for planetary nebulae have given the first identifications in Fornax, NGC 6822, M33, IC 10, Leo A, Sextans A, Pegasus, WLM, NGC 404, and M81, and extended the identifications in the SMC, the LMC, and M31. Observations of planetaries have established chemical compositions in old or intermediate age populations in 8 Local Group galaxies. The chemical compositions show that i) the helium abundance is higher in planetary nebulae than in H II regions in the same galaxy, and ii) nitrogen is overabundant relative to H II regions by factors of 4 to 100. Planetary nebulae are not a major source of helium in star-forming galaxies, and are a major source of nitrogen. The planetary in Fornax has a relatively high O abundance, and, together with Fornax's carbon stars, establishes the presence of at least 2 stellar populations. The abundance gradient derived from 3 planetaries in M31 is very shallow, and gives high abundances at ~ 20 kpc. By using planetary nebulae as standard candles, upper and lower distance limits have been set for 10 Local Group candidates, and a new distance estimated for M81.

scholarly journals What do planetary nebulae and H II regions reveal about the chemical evolution of nearby dwarf galaxies?

2018 ◽  
Vol 14 (S344) ◽  
pp. 161-177 ◽  
Author(s):  
Denise R. Gonçalves
Keyword(s):  
Chemical Evolution ◽  
Local Group ◽  
Planetary Nebulae ◽  
H Ii Regions ◽  
Chemical Abundances ◽  
Local Universe ◽  
Time Line ◽  
Nearby Galaxies ◽  
H Ii Region ◽  
Age Range

AbstractThe Local Group contains a great number of dwarf irregulars and spheroidals, for which the spectroscopy of individual stars can be obtained. Thus, the chemical evolution of these galaxies can be traced, with the only need of finding populations spanning a large age range and such that we can accurately derive the composition. Planetary nebulae (PNe) are old- and intermediate-age star remnants and their chemical abundances can be obtained up to 3-4 Mpc. H ii regions, which are brighter and much easily detected, represent galaxies young content. PNe and H ii regions share similar spectroscopic features and are analysed in the same way. Both are among the best tracers of the chemical evolution allowing to draw the chemical time line of nearby galaxies. The focus in this review are the PN and H ii region populations as constraints to the chemical evolution models and the mass-metallicity relation of the local universe.

Planetary Nebulae in Local-Group Galaxies. I. Identifications in NGC 185, NGC 205, and NGC 221

1973 ◽  
Vol 183 ◽  
pp. L73 ◽  
Author(s):  
Holland C. Ford ◽  
David C. Jenner ◽  
Harland W. Epps
Keyword(s):  
Local Group ◽  
Planetary Nebulae

Radial velocities of planetary nebulae

1983 ◽  
Vol 52 ◽  
pp. 399 ◽  
Author(s):  
S. E. Schneider ◽  
Y. Terzian ◽  
A. Purgathofer ◽  
M. Perinotto
Keyword(s):  
Planetary Nebulae ◽  
Radial Velocities
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