English
Related papers

Related papers: Exact solutions for the populations of the n-level…

200 papers

We compute the populations of isotopes of Boron, Carbon and Nitrogen measured experimentally in intermediate energy heavy ion collisions. A two component soluble statistical model is used to find the initial populations of different nuclei…

Nuclear Theory · Physics 2009-10-31 A. Majumder , S. Das Gupta

We present a tool, VELNEB_3D, which can be applied to the results of 3D photoionization codes to generate emission line profiles, position-velocity maps and 3D maps in any emission line by assuming an arbitrary velocity field. We give a few…

Astrophysics · Physics 2007-05-23 C. Morisset , G. Stasinska

An exactly solvable model for the multi-level system interacting with several reservoirs at zero temperatures is presented. Population decay rates and decoherence rates predicted by exact solution and several approximate master equations,…

Quantum Physics · Physics 2020-01-06 A. E. Teretenkov

Spectroscopic studies of extreme-ionization galaxies (EIGs) are critical to our understanding of exotic systems throughout cosmic time. These EIGs exhibit spectral features requiring >54.42 eV photons: the energy needed to fully ionize…

Thermodynamic quantities of Coulomb plasmas consisting of point-like ions immersed in a compressible, polarizable electron background are calculated for ion charges Z=1 to 26 and for a wide domain of plasma parameters ranging from the…

Plasma Physics · Physics 2016-09-08 G. Chabrier , A. Y. Potekhin

The assumption of spherical symmetry is not justified for the vast majority of PNe. The interpretation of spatially-resolved observations cannot rely solely on the application of 1D codes, which may yield incorrect abundances determinations…

Astrophysics · Physics 2009-11-11 B. Ercolano , M. J. Barlow , P. J. Storey

Configuration-interaction-type calculations on electronic and vibrational structure are often the method of choice for the reliable approximation of many-particle wave functions and energies. The exponential scaling, however, limits their…

Computational Physics · Physics 2019-05-24 Alberto Baiardi , Christopher J. Stein , Vincenzo Barone , Markus Reiher

We present spectrophotometry of 12 Galactic and 3 Magellanic Cloud planetary nebulae (PNe). Nine of the Galactic PNe were observed by scanning the slit across the PN. We use the fluxes of collisionally excited lines (CELs) to derive…

Astrophysics · Physics 2009-11-07 Y. G. Tsamis , M. J. Barlow , X. -W. Liu , I. J. Danziger , P. J. Storey

The study of photoionised gas in planetary nebulae (PNe) has played a major role achieving, over the years, a better understanding of a number of physical processes pertinent to a broader range of fields than just PNe studies, ranging from…

Astrophysics · Physics 2009-11-11 Barbara Ercolano

Mixed-precision computing has the potential to significantly reduce the cost of exascale computations, but determining when and how to implement it in programs can be challenging. In this article, we propose a methodology for enabling…

Mathematical Software · Computer Science 2025-07-02 Yanxiang Chen , Pablo de Oliveira Castro , Paolo Bientinesi , Niclas Jansson , Roman Iakymchuk

We present a new analysis of the main empirical calibrators of oxygen abundance for ionised gas nebulae. With that aim we have compiled an extensive sample of objects with emission line data including the near IR [SIII] lines and the weak…

Astrophysics · Physics 2011-07-18 Enrique Perez-Montero , Angeles I. Diaz

A hot central star illuminating the surrounding ionized H II region usually produces very rich atomic spectra resulting from basic atomic processes: photoionization, electron-ion recombination, bound-bound radiative transitions, and…

Astrophysics · Physics 2007-05-23 Sultana N. Nahar

We present an explicit solver of the three-dimensional screened and unscreened Poisson's equation which combines accuracy, computational efficiency and versatility. The solver, based on a mixed plane-wave / interpolating scaling function…

Materials Science · Physics 2013-03-27 Alessandro Cerioni , Luigi Genovese , Alessandro Mirone , Vicente Armando Sole

In the context of observations of the rest-frame ultraviolet and optical emission from distant galaxies, we explore the emission-line properties of photoionization models of active and inactive galaxies. Our aim is to identify new…

Astrophysics of Galaxies · Physics 2016-01-20 Anna Feltre , Stephane Charlot , Julia Gutkin

Recent state-of-the-art calculations of A-values and electron impact excitation rates for Fe III are used in conjunction with the Cloudy modeling code to derive emission line intensity ratios for optical transitions among the fine-structure…

Whenever observations are compared to theories, an estimate of the uncertainties associated with the observations is vital if the comparison is to be meaningful. However, many determinations of temperatures, densities and abundances in…

Astrophysics of Galaxies · Physics 2015-06-04 R. Wesson , D. J. Stock , P. Scicluna

High precision atomic data is indispensable for experiments involving studies of fundamental interactions, astrophysics, atomic clocks, plasma science, and others. We develop new parallel atomic structure codes and explore the difficulties…

Atomic Physics · Physics 2021-03-11 C. Cheung , M. S. Safronova , S. G. Porsev

The three-dimensional electrostatic field configuration in gas ionization detectors has been simulated using an efficient and precise nearly exact boundary element method (NEBEM) solver set up to solve an integral equation of the first…

Instrumentation and Detectors · Physics 2007-05-23 N. Majumdar , S. Mukhopadhyay

The emission lines emitted from gaseous nebulae carry valuable information about the physical conditions and chemical abundances of ionized gases in these objects, as well as the interstellar extinction. "proEQUIB" is a library containing…

Instrumentation and Methods for Astrophysics · Physics 2024-12-09 Ashkbiz Danehkar

The James Webb Space Telescope has ushered in an era of abundant high-redshift observations of young stellar populations characterized by strong emission lines, motivating us to integrate nebular emission into the new Maraston stellar…