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Related papers: New advances in nebular photoionisation modelling

200 papers

For decades, the theoretical understanding of planetary nebulae (PNe) has remained in tension with the observed universal bright-end cutoff of the PN luminosity function (PNLF). The brightest younger PN populations have been observed to be…

We analyse photoionisation and ion detection as a means of accurately counting ultra-cold atoms. We show that it is possible to count clouds containing many thousands of atoms with accuracies better than $N^{-1/2}$ with current technology.…

Other Condensed Matter · Physics 2016-08-16 T. Campey , C. J. Vale , M. J. Davis , S. Kraft , C. Zimmermann , J. Fortágh , N. R. Heckenberg , H. Rubinsztein-Dunlop

The survey of the nearby space and continuous monitoring of the Near Earth Objects (NEOs) and especially Near Earth Asteroids (NEAs) are essential for the future of our planet and should represent a priority for our solar system research…

The treatment of convection remains a major weakness in the modelling of stellar evolution with one-dimensional (1D) codes. The ever increasing computing power makes now possible to simulate in 3D part of a star for a fraction of its life,…

Solar and Stellar Astrophysics · Physics 2024-06-03 C. Georgy , F. Rizzuti , R. Hirschi , V. Varma , W. D. Arnett , C. Meakin , M. Mocak , A. StJ. Murphy , T. Rauscher

A three-dimensional Monte Carlo code for modelling radiation transport in Type Ia supernovae is described. In addition to tracking Monte Carlo quanta to follow the emission, scattering and deposition of radiative energy, a scheme involving…

Astrophysics · Physics 2008-11-26 S. A. Sim

Digital co-addition of astronomical images is a common technique for increasing signal-to-noise and image depth. A modification of this simple technique has been applied to the detection of minor bodies in the Solar System: first stationary…

Earth and Planetary Astrophysics · Physics 2015-05-18 Alex H. Parker , JJ. Kavelaars

Neutron stars are the densest, directly observable stellar objects in the universe and serve as unique astrophysical laboratories to study the behavior of matter under extreme physical conditions. This book chapter is devoted to describing…

High Energy Astrophysical Phenomena · Physics 2018-06-11 N. Degenaar , V. F. Suleimanov

Long-slit echellograms of the high excitation planetary nebula NGC1501, reduced according to the methodology developed by Sabbadin et al. (2000a, b), allowed us to obtain the ``true'' distribution of the ionized gas in the eight nebular…

Astrophysics · Physics 2009-11-06 R. Ragazzoni , E. Cappellaro , S. Benetti , M. Turatto , F. Sabbadin

We model the molecular emission from cometary knots in planetary nebulae (PNe) using a combination of photoionization and photodissociation region (PDR) codes, for a range of central star properties and gas densities. Without the inclusion…

Astrophysics of Galaxies · Physics 2018-05-16 F. D. Priestley , M. J. Barlow

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

Central to our understanding of stellar evolution and its impact on processes in our Galaxy and across the Universe is the study of mass loss. While the general framework is well established, recent JWST observations of objects like NGC…

We demonstrate a new image processing methodology for resolving gas bubbles travelling through liquid metal from dynamic neutron radiography images with intrinsically low signal-to-noise ratio. Image pre-processing, denoising and bubble…

Advances in stellar interior modeling are being driven by new data from large-scale surveys and high-precision photometric and spectroscopic observations. Here we focus on single stars in normal evolutionary phases; we will not discuss the…

Solar and Stellar Astrophysics · Physics 2015-05-19 Joyce Ann Guzik

Planetary nebulae (PNe) are strong H$\alpha$ line-emitters and a lot of new PNe discoveries have been made by the SuperCOSMOS AAO/UKST H$\alpha$ Survey (SHS) and the Isaac Newton Telescope Photometric H$\alpha$ Survey (IPHAS). However, the…

Solar and Stellar Astrophysics · Physics 2019-08-20 Stavros Akras , Lizette Guzman-Ramirez , Denise R. Gonçalves

Distant planetary nebulae (PNe) are used to measure distances through the PN luminosity function, as kinematic tracers in determining the mass distribution in elliptical galaxies, and most recently, for measuring the kinematics of the…

Astrophysics · Physics 2009-11-13 Ortwin Gerhard

Here we report new ${\it ab initio}$ calculations of the effective recombination coefficients for the \ion{N}{ii} recombination spectrum. We have taken into account the density dependence of the coefficients arising from the relative…

Solar and Stellar Astrophysics · Physics 2015-05-27 X. Fang , P. J. Storey , X. -W. Liu

High resolution images at different wavelengths show the common presence of structures and microstructures in planetary nebulae (PNe), which are not well incorporated to the existing models for the formation of these objects. We summarize…

Astrophysics · Physics 2007-05-23 Luis F. Miranda

Neural Radiance Fields (NeRFs) have remodeled 3D scene representation since release. NeRFs can effectively reconstruct complex 3D scenes from 2D images, advancing different fields and applications such as scene understanding, 3D content…

Computer Vision and Pattern Recognition · Computer Science 2025-12-10 Wenhui Xiao , Remi Chierchia , Rodrigo Santa Cruz , Xuesong Li , David Ahmedt-Aristizabal , Olivier Salvado , Clinton Fookes , Leo Lebrat

We develop a numerical code to calculate the neutrino transfer with multi-energy and multi-angle in three dimensions (3D) for the study of core-collapse supernovae. The numerical code solves the Boltzmann equations for neutrino…

High Energy Astrophysical Phenomena · Physics 2012-03-26 Kohsuke Sumiyoshi , Shoichi Yamada

Pulsar wind nebulae (PWNe) are the synchrotron bubbles inflated by the rotational energy of a neutron star. Observing variability within them has previously been limited to cases of significant brightening, or the few instances where…

High Energy Astrophysical Phenomena · Physics 2020-09-09 Benson Guest , Samar Safi-Harb