100 citations · 528 across the 57 of their papers we have counts for
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Physical Conditions and Chemical Abundances of the Variable Planetary Nebula IC 4997
A. Danehkar, M. Parthasarathy
The planetary nebula (PN) IC 4997 is one of a few rapidly evolving objects with variable brightness and nebular emission around a hydrogen-deficient star. In this study, we have de…
Morphologies of Wolf-Rayet Planetary Nebulae based on IFU Observations
A. Danehkar
Integral field unit (IFU) spectroscopy of planetary nebulae (PNe) provides a plethora of information about their morphologies and ionization structures. An IFU survey of a sample o…
3D spatio-kinematic modeling of Abell 48, a planetary nebula around a Wolf-Rayet [WN] star
A. Danehkar
The planetary nebula (PN) Abell 48 (PN G029.0+00.4) is around a rare Wolf-Rayet [WN5] star whose stellar history is as yet unknown. Using the integral field observations of the H$α…
Morpho-kinematic properties of Wolf-Rayet planetary nebulae
A. Danehkar
The majority of planetary nebulae (PNe) show axisymmetric morphologies, whose causes are not well understood. In this work, we present spatially resolved kinematic observations of…
Physical and chemical properties of Wolf-Rayet planetary nebulae
A. Danehkar
Wolf-Rayet ([WR]) and weak emission-line () central stars of planetary nebulae (PNe) have hydrogen-deficient atmospheres, whose origins are not well understood. In the presen…
Bi-abundance ionization structure of the Wolf-Rayet planetary nebula PB 8
Ashkbiz Danehkar
The planetary nebula (PN) PB 8 around a [WN/WC]-hybrid central star is one of PNe with moderate abundance discrepancy factors (ADFs ~ 2-3), which could be an indication of a tiny f…
Mapping Excitation in the Inner Regions of the Planetary Nebula NGC 5189 using HST WFC3 Imaging
Ashkbiz Danehkar, Margarita Karovska, W. Peter Maksym +1
The planetary nebula (PN) NGC 5189 around a Wolf-Rayet [WO] central star demonstrates one of the most remarkable complex morphologies among PNe with many multi-scale structures, sh…
Fast, low-ionization emission regions of the planetary nebula M2-42
A. Danehkar, Q. A. Parker, W. Steffen
Spatially resolved observations of the planetary nebula M2-42 (PN G008.2-04.8) obtained with the Wide Field Spectrograph on the Australian National University 2.3 m telescope have…
Discovery of collimated bipolar outflows in the planetary nebula Th 2-A
Ashkbiz Danehkar
We present a comprehensive set of spatially resolved, integral field spectroscopic mapping of the Wolf-Rayet planetary nebula Th 2-A, obtained using the Wide Field Spectrograph on…
Spatially resolved kinematic observations of the planetary nebulae Hen 3-1333 and Hen 2-113
Ashkbiz Danehkar, Quentin A. Parker
We have performed integral field spectroscopy of the planetary nebulae Hen 3-1333 (PNG332.9-09.9) and Hen 2-113 (PNG321.0+03.9), which are unusual in exhibiting dual-dust chemistry…
Kinematical Properties of Planetary Nebulae with WR-type Nuclei
Ashkbiz Danehkar, Wolfgang Steffen, Quentin A. Parker
We have carried out integral field unit (IFU) spectroscopy of H, [N II] and [O III] emission lines for a sample of Galactic planetary nebulae (PNe) with Wolf-Rayet (WR) stars an…
Physical and Chemical Properties of Planetary Nebulae with WR-type Nuclei
Ashkbiz Danehkar, Roger Wesson, Amanda Karakas +1
We have carried out optical spectroscopic measurements of emission lines for a sample of Galactic planetary nebulae with Wolf-Rayet (WR) stars and weak emission-line stars (wels).…
Observations and three-dimensional photoionization modelling of the Wolf-Rayet planetary nebula Abell 48
A. Danehkar, H. Todt, B. Ercolano +1
Recent observations reveal that the central star of the planetary nebula Abell 48 exhibits spectral features similar to massive nitrogen-sequence Wolf-Rayet stars. This raises a pe…
Observations and three-dimensional ionization structure of the planetary nebula SuWt 2
Ashkbiz Danehkar, Quentin A. Parker, Barbara Ercolano
The planetary nebula SuWt 2 (PN G311.0+02.4), is an unusual object with a prominent, inclined central emission ellipse and faint bipolar extensions. It has two A-type stars in a pr…
The planetary nebula Abell 48 and its [WN] nucleus
David J. Frew, Ivan S. Bojicic, Q. A. Parker +6
We have conducted a detailed multi-wavelength study of the peculiar nebula Abell 48 and its central star. We classify the nucleus as a helium-rich, hydrogen-deficient star of type…
Photoionization models of the Eskimo nebula: evidence for a binary central star?
Ashkbiz Danehkar, David J. Frew, Quentin A. Parker +1
The ionizing star of the planetary nebula NGC 2392 is too cool to explain the high excitation of the nebular shell, and an additional ionizing source is necessary. We use photoioni…
A search for Type Ia supernova progenitors: the central stars of the planetary nebulae NGC 2392 and NGC 6026
Ashkbiz Danehkar, David J. Frew, Orsola De Marco +1
We use photoionization modeling to assess the binary nature of the central stars of NGC 2392 and NGC 6026. If they are close binaries, they are potential Type Ia supernova (SN Ia)…
Large-amplitude electron-acoustic solitons in a dusty plasma with kappa-distributed electrons
N. S. Saini, A. Danehkar, M. A. Hellberg +1
The Sagdeev pseudopotential method is used to investigate the occurrence and the dynamics of fully nonlinear electrostatic solitary structures in a plasma containing suprathermal h…
Electron-acoustic solitary waves in the presence of a suprathermal electron component
Ashkbiz Danehkar, Nareshpal Singh Saini, Manfred A. Hellberg +1
The nonlinear dynamics of electron-acoustic localized structures in a collisionless and unmagnetized plasma consisting of "cool" inertial electrons, "hot" electrons having a kappa…