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 Emission Lines of Northern Planetary Nebulae

2016 ◽  
Vol 12 (S323) ◽  
pp. 333-334
Author(s):  
Nazim Aksaker ◽  
Sinan K. Yerli ◽  
Ümit Kızıloğlu ◽  
Betül Atalay
Keyword(s):  
Emission Line ◽  
Supernova Remnants ◽  
Planetary Nebulae ◽  
Hii Regions ◽  
Emission Lines ◽  
Line Flux ◽  
Chemical Abundances ◽  
Data Set ◽  
Standard Data ◽  
Spectrometric Measurements

AbstractIn this work, we present results of long slit spectrophotometric emission line flux observations of selected planetary nebulae (PNe). We have measured absolute fluxes and equivalent widths (EW) of all observable emission lines. In addition to these observations, electron temperatures (Te), densities (Ne), and chemical abundances were also calculated. The main purpose of this work is to fill the gaps in emission line flux standards for the northern hemisphere. It is expected that the measured fluxes would be used as standard data set for further photometric and spectrometric measurements of HII regions, supernova remnants etc.

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.

scholarly journals IFU Spectroscopy of Southern Planetary Nebulae V: Low-Ionisation Structures

2017 ◽  
Vol 34 ◽  
Author(s):  
A. Ali ◽  
M. A. Dopita
Keyword(s):  
Emission Line ◽  
Planetary Nebulae ◽  
Central Star ◽  
Chemical Compositions ◽  
Physical Analysis ◽  
Type I ◽  
High Excitation ◽  
Chemical Abundances ◽  
Physical Conditions ◽  
Integral Field Spectroscopy

AbstractIn this fifth paper of the series, we examine the spectroscopy and morphology of four southern Galactic planetary nebulae Hen 2-141, NGC 5307, IC 2553, and PB 6 using new integral field spectroscopy data. The morphologies and ionisation structures of the sample are given as a set of emission-line maps. In addition, the physical conditions, chemical compositions, and kinematical characteristics of these objects are derived. The results show that PB 6 and Hen 2-141 are of very high excitation classes and IC 2553 and NGC 5307 are mid to high excitation objects. The elemental abundances reveal that PB 6 is of Type I, Hen 2-141 and IC 2553 are of Type IIa, and NGC 5307 is of Type IIb/III. The observations unveil the presence of well-defined low-ionisation structures or ‘knots’ in all objects. The diagnostic diagrams reveal that the excitation mechanism of these knots is probably by photoionisation of dense material by the nebular central stars. The physical analysis of six of these knots show no significant differences with their surrounding nebular gas, except their lower electron densities. In spite of the enhancement of the low-ionisation emission lines of these knots, their chemical abundances are nearly comparable to their surrounding nebulae, with the exception of perhaps slightly higher nitrogen abundances in the NGC 5307 knots. The integrated spectrum of IC 2553 reveals that nearly all key lines that have led researchers to characterise its central star as a weak-emission line star type are in fact of nebular origin.

scholarly journals Chemical Abundances from Planetary Nebulae in Elliptical Galaxies

1995 ◽  
Vol 10 ◽  
pp. 483-485
Author(s):  
J.R. Walsh
Keyword(s):  
Local Group ◽  
Elliptical Galaxy ◽  
Planetary Nebulae ◽  
Elliptical Galaxies ◽  
Line Flux ◽  
Chemical Abundances ◽  
High Quality ◽  
Ccd Photometry ◽  
S0 Galaxies

Currently over 2000 Planetary Nebulae (PN) have been detected in Local Group E and S0 galaxies by on/off band [O III]5007Å CCD photometry. PN can currently be detected out to Fornax and Virgo clusters.The magnitude of the brightest PN in the nearest elliptical galaxy (NGC 205) is m5007 20.7 (Ciardullo et al, 1989); for NGC 5128 (Cen-A) it is 23.5 (Hui et al, 1993a) and ≥ 25.6 for Virgo ellipticals (Jacoby et al, 1990). Given the relation between m5007 and line flux:m5007 = −2.5 log F5007 − 13.74the typical Hβ fluxes are ≤1.5×10-16 ergs cm−2 s−1 for NGC 5128 PN and ≤ 2.5×10−17 for Virgo PN. Obtaining spectra of these faint emisison lines is clearly a challenge. The only PN spectra studied in Local Group galaxies are 1 PN in M32 (NGC 221) (Log F(H/β) = −14.9; Jenner et al, 1979) and recently 15 in NGC 205 (Jacoby et al, 1995). None of the spectra are of high quality and the Te diagnostic line [O III]4363Å was not detected. There is evidence of possible high N abundance in the M32 PN.

Exsiccatae in the bryophyte collection of the National Herbarium, Pretoria

Bothalia ◽  
2013 ◽  
Vol 43 (1) ◽  
pp. 55-66 ◽  
Author(s):  
J. Van Rooy
Keyword(s):  
South Africa ◽  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Transfer Of Knowledge ◽  
National Herbarium ◽  
The Usa ◽  
First Time

Exsiccatae in the bryophyte collection of the National Herbarium in Pretoria (PRE) are catalogued for the first time. Most of the 66 series represented in PRE were issued in Europe, but the USA is the country where the largest number of exsiccatae originated. The exsiccatae span three centuries, with the earliest specimens issued in 1845 and the latest in 2009. This indicates the long-standing exchange of material and transfer of knowledge between herbaria in South Africa and countries of the northern Hemisphere. Many of the exsiccatae in PRE are incomplete and specimens were received as duplicates in exchange sets rather than exsiccatae. PRE houses a number of important African and southern hemisphere exsiccatae including two different sets of A. Rehmann’s Musci Austro-Africani (1875–1877) and Musci Austro-Africani cont., and R. Ochyra’s Bryophyta Antarctica exsiccata.

Additions to the genus Mycobilimbia s. lat. from the Southern Hemisphere

2005 ◽  
Vol 37 (3) ◽  
pp. 251-259 ◽  
Author(s):  
Gintaras KANTVILAS ◽  
María Inés MESSUTI ◽  
H. Thorsten LUMBSCH
Keyword(s):  
New Species ◽  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Similar Species ◽  
Two New Species ◽  
First Time

Two new species of Mycobilimbia are described and compared with other members of the genus: Mycobilimbia australis Kantvilas & Messuti from austral, cool to cold temperate regions, and Mycobilimbia meridionalis Kantvilas from Tasmania. Two additional, superficially similar species that are widespread in the Northern Hemisphere, M. hypnorum (Lib.) Kalb & Hafellner and Bilimbia lobulata (Sommerf.) Hafellner & Coppins, are recorded from Tasmania for the first time.

scholarly journals A Digital Emission-Line Survey of the Small Magellanic Cloud

1999 ◽  
Vol 190 ◽  
pp. 97-98
Author(s):  
P. Frank Winkler ◽  
Yasser Rathore ◽  
R. Chris Smith
Keyword(s):  
Emission Line ◽  
Supernova Remnants ◽  
Planetary Nebulae ◽  
Magellanic Cloud ◽  
H Ii Regions ◽  
Small Magellanic Cloud ◽  
Rich Variety ◽  
Line Survey ◽  
The Rich ◽  
Mosaic Images

We present results on the SMC from the first full season of the Michigan/CTIO Magellanic Cloud Emission-Line Survey, being carried out from CTIO. Images are being obtained in Hα, [S II] λλ 6717, 6731, and [O III] λ 5007, plus red and green continuum bands for star subtraction. Data from the 1996–97 season have been assembled into large mosaic images which reveal the rich variety of nebulosity in the SMC in unprecedented detail. These are providing definitive samples of the active, occasionally violent, ISM on scales including superbubbles, wind-blown bubbles, supernova remnants, H II regions, and planetary nebulae.

scholarly journals Buellia epigaea (Pers.) Tuck , a new record of lichenized fungus species for Antarctica

2021 ◽  
Vol 11 (1) ◽  
pp. 9-15
Author(s):  
Merve Kahraman ◽  
Mehmet Gökhan Halıcı
Keyword(s):  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Related Species ◽  
New Record ◽  
Fungal Species ◽  
Molecular Characteristics ◽  
Fungus Species ◽  
Lichenized Fungus ◽  
First Time

Buellia epigaea, a terricolous lichenized fungal species known from numerous localities in Northern Hemisphere, but only from Australia in Southern Hemisphere, is reported from Antarctica for the first time. Here we provide morphological, anatomical, and molecular characteristics (nrITS) of this species. Besides, the differences of B. epigaea with morphologically, ecologically or phylogenetically related species are discussed.

Molecular studies reveal a new species of Bryoria in Chile

2015 ◽  
Vol 47 (6) ◽  
pp. 387-394 ◽  
Author(s):  
Carlos G. Boluda ◽  
Pradeep K. Divakar ◽  
David L. Hawksworth ◽  
Johana Villagra ◽  
Víctor J. Rico
Keyword(s):  
New Species ◽  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Molecular Data ◽  
Phylogenetic Data ◽  
Molecular Studies ◽  
First Time ◽  
A New Species

AbstractBryoria araucana sp. nov. is described from Chile on the basis of morphological, chemical and molecular data. It has a grey to dark greyish brown pendent thallus with the base usually black, branching angles mainly obtuse, terminal branches with few lateral branchlets acutely inserted, fumarprotocetraric acid, and often protocetraric and confumarprotocetraric acids. It is morphologically similar to the Northern Hemisphere B. trichodes, but lacks soralia and has inconspicuous concolorous or slightly darker pseudocyphellae. Bryoria glabra is also reported for the first time from the Southern Hemisphere. New phylogenetic data based on ITS, mtSSU and MCM7 analyses suggest that Bryoria sect. Bryoria is polyphyletic and needs revision.

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