English
Related papers

Related papers: Modelling of aspherical nebulae. I. A quick pseudo…

200 papers

We developed a computer vision-based methodology to achieve precise 3D segmentation and tracking of superbubbles within magnetohydrodynamic simulations of the supernova-driven interstellar medium. Leveraging advanced 3D transformer models,…

Astrophysics of Galaxies · Physics 2026-03-31 Jing-Wen Chen , Alex S. Hill , Anna Ordog , Rebecca A. Booth , Mohamed S. Shehata

(Abridged) We examine standard methods of measuring nebular chemical abundances, including estimates based on direct T_e measurements, and also bright-line diagnostics. We use observations of 4 LMC HII regions whose ionizing stars have…

Astrophysics · Physics 2009-10-31 M. S. Oey , J. C. Shields

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 pertinent question, whether it is still a planetary nebula or…

Solar and Stellar Astrophysics · Physics 2014-03-27 A. Danehkar , H. Todt , B. Ercolano , A. Y. Kniazev

A nebular analysis of the central Orion Nebula and its main structures is presented. We exploit MUSE integral field observations in the wavelength range 4595-9366 \r{A} to produce the first O, S and N ionic and total abundance maps of a…

Astrophysics of Galaxies · Physics 2015-12-10 A. F. Mc Leod , P. M. Weilbacher , A. Ginsburg , J. E. Dale , S. Ramsay , L. Testi

We estimate distances to the spherical planetary nebula Abell 39 and the bipolar planetary nebula NGC 7027 by interpolating from a wide grid of photoionization models using the 3-D code, MOCASSIN. We find preliminary distances of 1.5 kpc…

Astrophysics of Galaxies · Physics 2012-09-11 Ashkbiz Danehkar , David J. Frew , Quentin A. Parker , Orsola De Marco

Modern instrumentation in radioastronomy constitutes a valuable tool for studying the Universe: ALMA has reached unprecedented sensitivities and spatial resolution, while Herschel/HIFI has opened a new window for probing molecular warm gas…

Instrumentation and Methods for Astrophysics · Physics 2014-12-17 M. Santander-Garcia , V. Bujarrabal , N. Koning , W. Steffen

The study of photoionized environments is fundamental to many astrophysical problems. Up to the present most photoionization codes have numerically solved the equations of radiative transfer by making the extreme simplifying assumption of…

Astrophysics · Physics 2009-11-07 B. Ercolano , M. J. Barlow , P. J. Storey , X. -W. Liu

Accounting for nebular emission when modeling galaxy spectral energy distributions (SEDs) is important, as both line and continuum emission can contribute significantly to the total observed flux. In this work, we present a new nebular…

Astrophysics of Galaxies · Physics 2017-05-10 Nell Byler , Julianne J. Dalcanton , Charlie Conroy , Benjamin D. Johnson

Radiative cooling plays a crucial role in the dynamics of many astrophysical flows, and is particularly important in the dense shocked gas within Herbig-Haro (HH) objects and stellar jets. Simulating cooling processes accurately is…

High Energy Astrophysical Phenomena · Physics 2018-11-19 E. C. Hansen , P. Hartigan , A. Frank. A. Wright , J. C. Raymond

We present a new approach to study planetary nebulae using integral field spectroscopy. VLT@VIMOS datacube of the planetary nebula Abell 14 is analysed in three different ways by extracting: (i) the integrated spectrum, (ii) 1-dimensional…

Astrophysics of Galaxies · Physics 2020-03-02 Stavros Akras , Hektor Monteiro , Isabel Aleman , Marcos A. F. Farias , D. May , Claudio B. Pereira

We present integral field unit (IFU) spectroscopy and self-consistent photoionisation modelling for a sample of four southern Galactic planetary nebulae (PNe) with supposed weak emission-line (WEL) central stars. The Wide Field Spectrograph…

Solar and Stellar Astrophysics · Physics 2016-03-16 Hassan M. Basurah , Alaa Ali , Michael A. Dopita , R. Alsulami , Morsi A. Amer , A. Alruhaili

We apply an axially symmetric pseudo-3D photoionization model, pyCloudy, to derive the structures of 6 bipolar nebulae and 2 suggested post-bipolars in a quest to constrain the bipolar planetary nebulae evolution. HST images and VLT/UVES…

Solar and Stellar Astrophysics · Physics 2015-12-22 K. Gesicki , A. A. Zijlstra , C. Morisset

The quantitative spectroscopy of stellar objects in complex environments is mainly limited by the ability of separating the object from the background. Standard slit spectroscopy, restricting the field of view to one dimension, is obviously…

Astrophysics · Physics 2009-11-10 Thomas Becker , Sergei Fabrika , Martin M. Roth

Using a radiation-gasdynamics code the evolution of spherical planetary nebulae is followed, while taking into account the evolution of central star and the fast wind. These models show the importance of ionization fronts for the structure…

Astrophysics · Physics 2007-05-23 Garrelt Mellema

We introduce a novel approach to modelling the nebular emission from star-forming galaxies by combining the contributions from many HII regions incorporating loose trends in physical properties, random dust attenuation, a predefined Halpha…

The shape of the OB-star spectral energy distribution is a critical component in many diagnostics of the ISM and galaxy properties. We use single-star HII regions from the LMC to quantitatively examine the ionizing SEDs from widely…

Astrophysics of Galaxies · Physics 2013-06-28 Jordan Zastrow , M. S. Oey , E. W. Pellegrini

Understanding the explosion mechanism and hydrodynamic evolution of core-collapse supernovae is a long-standing quest in astronomy. The asymmetries caused by the explosion are encoded into the line profiles which appear in the nebular phase…

High Energy Astrophysical Phenomena · Physics 2024-04-03 Bart van Baal , Anders Jerkstrand , Annop Wongwathanarat , Thomas Janka

The gas that is present in the interstellar medium is usually very far removed from (local) thermodynamic equilibrium, and in some cases may also not be in a steady-state equilibrium with its surroundings. The physics of this material is…

Solar and Stellar Astrophysics · Physics 2020-02-17 P. A. M. van Hoof , G. C. Van de Steene , F. Guzmán , M. Dehghanian , M. Chatzikos , G. J. Ferland

We present the first results of a project aimed at the combined study of massive stars and their surrounding nebulae by means of a detailed study of Galactic HII regions ionized by only one massive star. With this, we intend to check the…

Evolved stars are among the largest and brightest stars and they are ideal targets for the new generation of sensitive, high resolution instrumentation that provides spectrophotometric, interferometric, astrometric, and imaging observables.…

Solar and Stellar Astrophysics · Physics 2015-12-16 A. Chiavassa , B. Freytag