scholarly journals Morphological and kinematical analysis of the planetary nebula Hu 1-2 and its irradiated bow-shocks

2011 ◽  
Vol 7 (S283) ◽  
pp. 440-441
Author(s):  
Luis F. Miranda ◽  
Mónica Blanco ◽  
Martín A. Guerrero ◽  
Angels Riera
Keyword(s):  
High Resolution ◽  
High Velocity ◽  
Planetary Nebula ◽  
Narrow Band ◽  
Central Star ◽  
Kinematical Analysis ◽  
Near Ir ◽  
Bow Shocks

AbstractWe present narrow-band optical and near-IR images, and high-resolution long-slit spectra of the planetary nebula Hu 1-2 that allow us to make a detailed description of its unusual morphology and internal kinematics. The data also reveal that the ansae of Hu 1-2 probably represent bow-shocks associated to high velocity outflows that are irradiated from the central star.

scholarly journals Near- and Mid-Infrared Imaging of the PN IC 418

1993 ◽  
Vol 155 ◽  
pp. 210-210
Author(s):  
J. L. Hora ◽  
L. K. Deutsch ◽  
W. F. Hoffmann ◽  
G. G. Fazio ◽  
K. Shivanandan
Keyword(s):  
High Resolution ◽  
Planetary Nebula ◽  
Infrared Imaging ◽  
Central Star ◽  
Infrared Images ◽  
Mid Infrared ◽  
Near Ir ◽  
Ir Emission ◽  
Array Camera ◽  
Infrared Array

We present high-resolution near- and mid-infrared images of the planetary nebula IC 418 at 1.2 (J), 1.6 (H), 2.2 (K), 9.8, and 11.7 μm. The near-IR images were obtained with a 64×64 pixel Hg:Cd:Te array camera, and the mid-IR images were obtained using the new 20×64 pixel Mid-Infrared Array Camera (MIRAC). The size of IC 418 in the near-IR is seen to vary with wavelength, being largest at K and smallest at J. Differences in the morphology of the nebula are seen between the J and K images. There is excess near-IR emission in the center of the nebula, after subtracting out the emission from the central star. Faint halo emission is detected at H and K, extending to a total diameter of approximately 40″. The 9.8 μm emission is distributed nonsymmetrically, with the peak in the NE lobe.

scholarly journals High Velocity Outflows in IRAS 17423-1755

1993 ◽  
Vol 155 ◽  
pp. 348-348
Author(s):  
A. Riera ◽  
P. García-Lario ◽  
A. Manchado ◽  
S.R. Pottasch
Keyword(s):  
High Resolution ◽  
High Velocity ◽  
Planetary Nebula ◽  
Optical Spectra ◽  
Bipolar Structure ◽  
La Palma ◽  
Pn Stage ◽  
Observational Program

IRAS 17423-1755 is a new transition object between the post-AGB phase and the planetary nebula (PN) stage included in an observational program of IRAS sources with infrared colours similar to those of PNe. We have taken B, V, R, I, Z, Hα and [OIII] CCD images at the 1m JKT (Roque de los Muchachos, La Palma), where a clearly marked bipolar structure with a total extension of about 10″ can be seen, and long slit (low and high resolution) optical spectra at the 4.2m WHT, 2.5m INT (RM, La Palma) and ESO 1.5m (La Silla) telescopes.

scholarly journals The Structure of the HH39 Region

1987 ◽  
Vol 115 ◽  
pp. 340-341
Author(s):  
J. R. Walsh
Keyword(s):  
High Resolution ◽  
Radial Velocity ◽  
Proper Motion ◽  
High Velocity ◽  
Velocity Structure ◽  
The Other ◽  
Emission Lines ◽  
High Resolution Spectroscopy ◽  
Bow Shocks ◽  
Hh Objects

HH39 is the group of Herbig-Haro (HH) objects associated with the young semi-stellar object R Monocerotis (R Mon) and the variable reflection nebula NGC 2261. An R CCD frame and a B prime focus plate of the region show a filament connecting NGC 2261 with HH39, confirming the association between R Mon and the HH objects. This filament is probably composed of emission material. The southern knot in HH39 has brightened over the last 20 years; its proper motion has been determined and is similar to that of the other knots. A total of 8 knots can be distinguished in HH39 surrounded by diffuse nebulosity. High resolution spectroscopy of the Hα and [N II] emission lines shows the spatial variation of the radial velocity structure over the largest knots (HH39 A and C). Distinct differences in excitation and velocity structure between the knots are apparent. The observations are compatible with the knots being high velocity ejecta from R Mon, decelerated by interaction with ambient material and with bow shocks on their front surfaces.

scholarly journals The Dust in the Hydrogen-Poor Ejecta of Abell 30

1993 ◽  
Vol 155 ◽  
pp. 386-386
Author(s):  
J.P. Harrington ◽  
K.J. Borkowski ◽  
W.P. Blair ◽  
J. Bregman
Keyword(s):  
High Resolution ◽  
Amorphous Carbon ◽  
Ir Spectrum ◽  
Stellar Wind ◽  
Thermal Emission ◽  
Central Star ◽  
Near Ir ◽  
High Resolution Images ◽  
Small Grains ◽  
Ir Emission

High-resolution images in [O III] λ5007 of the hydrogen-poor knots of Abell 30 reveal comet-like structures which may be indicative of interaction with the stellar wind. In the near IR, new, higher-resolution, K-band images show an equatorial ring of hot dust that corresponds closely to optical knots 2 and 4 of Jacoby and Ford, while their polar knots 1 and 3 show no comparable IR emission. Both the thermal IR emission and the heavy internal extinction of the central star demands an extremely dusty ejecta. Greenstein showed that the UV extinction curve is fit by amorphous carbon. Our comprehensive dust models consider both the UV extinction and the IR emission from a population of carbon grains. The thermal emission from larger grains produces the far IR emission, while the stochastic heating of very small grains to high temperatures is essential to explain the near IR flux. We are able to reproduce the shape of the near IR spectrum with an a−3.0 distribution of grain radii which extends down to a minimum grain radius of 8 Å.

scholarly journals The past, present and future of Galactic planetary nebula surveys

2011 ◽  
Vol 7 (S283) ◽  
pp. 9-16 ◽  
Author(s):  
Quentin A. Parker ◽  
David J. Frew ◽  
Agnes Acker ◽  
Brent Miszalski
Keyword(s):  
Stellar Evolution ◽  
Planetary Nebula ◽  
Galactic Plane ◽  
Narrow Band ◽  
High Sensitivity ◽  
Window Of Opportunity ◽  
The Past ◽  
Near Ir ◽  
Multi Wavelength ◽  
Galactic Planetary Nebula

AbstractOver the last decade Galactic planetary nebula discoveries have entered a golden age due to the emergence of high sensitivity, high resolution narrow-band surveys of the Galactic plane. These have been coupled with access to complimentary, deep, multi-wavelength surveys across near-IR, mid-IR and radio regimes in particular from both ground-based and space-based telescopes. These have provided powerful diagnostic and discovery capabilities. In this review these advances are put in the context of what has gone before, what we are uncovering now and through the window of opportunity that awaits in the future. The astrophysical potential of this brief but key phase of late stage stellar evolution is finally being realised.

scholarly journals Planetary nebulae with Wolf-Rayet-type central stars - II. Dissecting the compact planetary nebula M 2-31 with GTC MEGARA

2021 ◽  
Author(s):  
J S Rechy-García ◽  
J A Toalá ◽  
S Cazzoli ◽  
M A Guerrero ◽  
L Sabin ◽  
...  
Keyword(s):  
Planetary Nebula ◽  
Spectral Properties ◽  
Narrow Band ◽  
Central Star ◽  
Comprehensive Analysis ◽  
High Dispersion ◽  
Medium Resolution ◽  
First Time ◽  
Integral Field ◽  
Central Stars

Abstract We present a comprehensive analysis of the compact planetary nebula M 2-31 investigating its spectral properties, spatio-kinematical structure and chemical composition using GTC MEGARA integral field spectroscopic observations and NOT ALFOSC medium-resolution spectra and narrow-band images. The GTC MEGARA high-dispersion observations have remarkable tomographic capabilities, producing an unprecedented view of the morphology and kinematics of M 2-31 that discloses a fast spectroscopic bipolar outflow along position angles 50○ and 230○, an extended shell and a toroidal structure or waist surrounding the central star perpendicularly aligned with the fast outflows. These observations also show that the C ii emission is confined in the central region and enclosed by the [N ii] emission. This is the first time that the spatial segregation revealed by a 2D map of the C ii line implies the presence of multiple plasma components. The deep NOT ALFOSC observations allowed us to detect broad WR features from the central star of M 2-31, including previously undetected broad O vi lines that suggest a reclassification as a [WO4]-type star.

scholarly journals The very fast evolution of Sakurai's object

2016 ◽  
Vol 12 (S323) ◽  
pp. 380-381 ◽  
Author(s):  
G. C. Van de Steene ◽  
P. A. M. van Hoof ◽  
S. Kimeswenger ◽  
A. A. Zijlstra ◽  
A. Avison ◽  
...  
Keyword(s):  
High Resolution ◽  
Emission Line ◽  
Planetary Nebula ◽  
Temporal Evolution ◽  
Optical Emission ◽  
Central Star ◽  
Evolutionary Models ◽  
Thermal Pulse ◽  
Emission Line Spectrum ◽  
Fast Evolution

AbstractV4334 Sgr (a.k.a. Sakurai's object) is the central star of an old planetary nebula that underwent a very late thermal pulse a few years before its discovery in 1996. We have been monitoring the evolution of the optical emission line spectrum since 2001. The goal is to improve the evolutionary models by constraining them with the temporal evolution of the central star temperature. In addition the high resolution spectral observations obtained by X-shooter and ALMA show the temporal evolution of the different morphological components.

scholarly journals High-Resolution Spectroscopy of the Planetary Nebulae PM 1–242, PM 1–318 and PM 1–322

2010 ◽  
Vol 27 (2) ◽  
pp. 199-202 ◽  
Author(s):  
L. F. Miranda ◽  
R. Vázquez ◽  
M. A. Guerrero ◽  
C. B. Pereira ◽  
E. Iñiguez-Garín
Keyword(s):  
High Resolution ◽  
Planetary Nebula ◽  
Planetary Nebulae ◽  
Central Star ◽  
Brightness Distribution ◽  
Physical Structure ◽  
High Resolution Spectroscopy

AbstractWe have recently confirmed the planetary nebula (PN) nature of PM 1–242, PM 1–318 and PM 1–322. Here we present high-resolution long-slit spectra of these three PNe in order to analyze their internal kinematics and to investigate their physical structure. PM 1–242 is a tilted ring and not an elliptical PN as suggested by direct images. The object is probably related to ring-like PNe and shows an unusual pointsymmetric brightness distribution in the ring. PM 1–318 is a pole-on elliptical PN, instead of a circular one as suggested by direct images. PM 1–322 is spatially unresolved and its spectrum shows large differences between the forbidden lines and Hα profiles, with the latter showing a double-peaked profile and relatively extended wings (FWZI ~325 km s−1). These properties are found in other PNe that are suspected to host a symbiotic central star.

scholarly journals High-resolution spectroscopic study of the planetary nebula Abell 78

1999 ◽  
Vol 193 ◽  
pp. 374-375
Author(s):  
Selene Medina ◽  
Miriam Peña
Keyword(s):  
Chemical Composition ◽  
High Resolution ◽  
Spectroscopic Study ◽  
Spectral Resolution ◽  
Planetary Nebula ◽  
Planetary Nebulae ◽  
Central Star ◽  
Heavy Elements ◽  
Physical Parameters ◽  
Processed Material

High resolution optical spectra of the planetary nebula Abell 78 were gathered, covering the wavelength ranges 3500–6600 Å and 3358–7361 Å, with a spectral resolution of ∼0.1 Å. Two different regions of Abell 78 are analyzed: the strongest knot near the central star which is thought to be a mass-loaded wind from the central star, and the outer, hydrogen-rich envelope. Physical parameters and chemical composition of both regions are estimated. The inner knot appears to be cooler and denser than the hydrogen-rich envelope. The chemical composition of the inner knot shows that there is almost no hydrogen near the central star and the emission is dominated by helium and processed material which has been dredged-up from the inner layers of the star. The outer, hydrogen-rich envelope appears to be deficient in heavy elements, mainly in oxygen, compared to the average abundances that are found among galactic planetary nebulae.

scholarly journals The Proto-Planetary Nebula Vy 2-2

1989 ◽  
Vol 131 ◽  
pp. 443-443 ◽  
Author(s):  
R. E. S. Clegg ◽  
M. G. Hoare ◽  
J. R. Walsh
Keyword(s):  
Ir Spectroscopy ◽  
Electron Temperature ◽  
Empirical Analysis ◽  
Planetary Nebula ◽  
Black Body ◽  
Central Star ◽  
Speckle Interferometry ◽  
Maser Emission ◽  
Near Ir ◽  
Carbon Abundance

High and low-resolution optical and near-IR spectroscopy of the candidate proto-planetary (or very young PN) Vy 2-2 (P-K 45 - 2°1) is reported. This object has associated OH maser emission and an angular diameter of only 0.4 arcsec, found from VLA and optical speckle interferometry. Empirical analysis gives the values Ne ≈3 × 105 cm−3, Te=11000(±1500)K. The electron temperature is quite uncertain because of the high density. Abundances of He, C, N, O, Ne and Ar are reported; the carbon abundance is uncertain as it relies on the C II λ4267Å line, since the object is too highly-reddened (c=1.8 ± 0.2) to be observed with IUE. We find He/H=0.10, O/H=4 × 10−4 and C/O=0.8. The HI Zanstra temperature is 38 000 K (for black-body). The spectrum shows broad stellar lines of He II λ4686, C III λ4647 and N III λ4640; the central star may be of type Of.

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