scholarly journals Emission-Line Profiles in Planetary Nebulae

1968 ◽  
Vol 34 ◽  
pp. 267-269
Author(s):  
Donald E. Osterbrock
Keyword(s):  
Velocity Distribution ◽  
Emission Line ◽  
Observational Data ◽  
Planetary Nebulae ◽  
Line Profiles ◽  
Measured Velocity ◽  
Hydrodynamical Models ◽  
Internal Velocity ◽  
First Time

This research was undertaken with the idea of measuring as accurately as possible the internal-velocity distribution in planetary nebulae, in order to compare the observational measurements with hydrodynamical models of expanding nebulae. Much of the work was done in collaboration with J. S. Miller and D.W. Weedman. All the observational data were obtained photographically with the Coudé spectrograph of the 100-inch telescope at Mt. Wilson, using an image rotator, a 900 line/mm grating, and an F/5-2 camera, giving a dispersion of about 4 Å/mm in the blue and about 6 Å/mm in the red. The measured velocity resolution is approximately 5–6 km/sec. The data for five nebulae have been published (Osterbrock et al., 1966) while data for three more, NGC 2392, NGC 3242, and IC 418 are discussed here for the first time.

Emission-Line Profiles in Planetary Nebulae

1966 ◽  
Vol 145 ◽  
pp. 697 ◽  
Author(s):  
D. E. Osterbrock ◽  
J. S. Miller ◽  
D. W. Weedman
Keyword(s):  
Emission Line ◽  
Planetary Nebulae ◽  
Line Profiles

scholarly journals Emission-Line Fluxes of Northern Planetary Nebulae

2015 ◽  
Vol 32 ◽  
Author(s):  
N. Aksaker ◽  
S. K. Yerli ◽  
Ü Kızıloğlu ◽  
B. Atalay
Keyword(s):  
Emission Line ◽  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Supernova Remnants ◽  
Planetary Nebulae ◽  
Line Flux ◽  
Chemical Abundances ◽  
Flux Measurements ◽  
First Time

AbstractWe present long slit spectrophotometric emission line fluxes of bright and extended (< 5 arcsec in diameter) planetary nebulae (PNe), selected from a catalogue with suitable equatorial coordinates for northern hemisphere. In total, 17 planetary nebulae have been chosen and observed in 2008–2010. To measure absolute fluxes, broad slit sizes, ranging from 3.5 to 7.5 arcsec were used and thus equivalent widths (EW) of all observable emission line fluxes were also calculated. Among 17 planetary nebulae observed, line flux measurements of 12 of them were made for the first time. This work also aims to extend the sky coverage of emission line flux standards in northern hemisphere (52 planetary nebulae in southern hemisphere; 6 planetary nebulae in northern hemisphere). Electron temperatures and densities, and chemical abundances of these planetary nebulae were also calculated in this work. These data are expected to lead the photometric or spectrometric further work for absolute emission line flux measurements needed for H ii regions, supernova remnants etc.

scholarly journals Solar EUV Rocket Telescope and Spectrograph (SERTS) Observations of Fe XII Emission Lines

1996 ◽  
Vol 152 ◽  
pp. 531-536
Author(s):  
F.P. Keenan ◽  
R.J. Thomas ◽  
W.M. Neupert ◽  
V.J. Foster ◽  
C.J. Greer ◽  
...  
Keyword(s):  
Active Region ◽  
Emission Line ◽  
Electron Temperature ◽  
Observational Data ◽  
Electron Density ◽  
Wavelength Range ◽  
Solar Spectrum ◽  
Emission Lines ◽  
First Time ◽  
Good Agreement

Abstract.Theoretical electron density sensitive emission line ratios involving transitions in the 186–383 Å wavelength range are compared with observational data for a solar active region and a subflare, obtained by the Solar EUV Rocket Telescope and Spectrograph (SERTS). Electron densities derived from the majority of the ratios are consistent with one another, and are also in good agreement with the values of density estimated from diagnostic lines in other species formed at similar temperatures to Fe XII. These results provide observational support for the general accuracy of the diagnostic calculations. In addition, our analysis indicates that a line at 283.70 Å in the active region spectrum is the 3s23p32D3/2−3s3p42P1/2 transition in Fe XII, the first time (to the best of our knowledge) that this line has been identified in the solar spectrum. Several of the line ratios considered are predicted to be relatively insensitive to the adopted electron temperature and density, and the generally good agreement found between theory and observation for these provides evidence for the reliability of the SERTS instrument calibration. The application of the Fe XII diagnostics to EUVE observations of the F5 subgiant Procyon is briefly discussed.

scholarly journals The kinematics of evolved planetary nebulae

2011 ◽  
Vol 7 (S283) ◽  
pp. 472-473
Author(s):  
E. Margarita Pereyra ◽  
Michael G. Richer ◽  
Jose-Alberto López
Keyword(s):  
Emission Line ◽  
Planetary Nebulae ◽  
Kinematic Characteristic ◽  
Hydrodynamical Models ◽  
Spatially Resolved ◽  
San Pedro ◽  
Advanced Stages ◽  
Photo Ionization ◽  
Echelle Spectroscopy ◽  
Late Stages

AbstractWe have selected a group of 85 evolved planetary nebulae to study their kinematic characteristic based on spatially resolved, long-slit echelle spectroscopy. The data have been drawn from the San Pedro Mártir Kinematic Catalogue of PNe. The aim is to characterize in detail the global kinematics of PNe at advanced stages of evolution with the largest sample of homogenous data used to date for this purpose. The results reveal groups that share kinematic and photo-ionization characteristics of the nebular shell at the different late stages under study. The expansion velocities are typically larger than seen in earlier evolutionary stages, with the largest velocities occurring in objects with very weak or absent [N II]λλ6548, 6584 emission line. These results shall serve to be compared to predictions of hydrodynamical models.

scholarly journals Scattering by Dust in Planetary Nebulae: Polarization as a Diagnostic Tool

2003 ◽  
Vol 209 ◽  
pp. 321-322
Author(s):  
J. R. Walsh ◽  
L. Walsh
Keyword(s):  
Emission Line ◽  
Linear Polarization ◽  
Diagnostic Tool ◽  
Line Emission ◽  
Planetary Nebulae ◽  
Central Star ◽  
Line Profiles ◽  
Gaseous Emission ◽  
Atmospheric Scattering ◽  
Spatially Varying

There is a wealth of evidence for the presence of dust in PN from continuum and line emission in the IR, spatially varying extinction and ERE emission in the optical and strength of resonance lines in the UV. The dust emits strongly in the IR but in the UV-optical absorbs and scatters the radiation from the central star and the gaseous emission envelope. Linear polarization of PN light is thus an expected consequence of the presence of dust both within and outside the ionized region. Intrinsic scattering haloes of PN can be confused with local (telescope + atmospheric) scattering; polarimetry however allows the morphology of a dusty halo to be studied. Spectropolarimetry of emission line profiles allows the kinematics of the dust relative to the gaseous emission to be uniquely studied. Polarization contributes to understanding the scattering properties of the grains in PN and how they relate to those of the general ISM to which they will subsequently contribute.

scholarly journals A Catalog of Emission line profiles for Planetary Nebulae

2006 ◽  
Vol 2 (S234) ◽  
pp. 465 ◽  
Author(s):  
Christophe Morisset ◽  
Grazyna Stasinska
Keyword(s):  
Emission Line ◽  
Planetary Nebulae ◽  
Line Profiles
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