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Related papers: Atomic Processes in Planetary Nebulae and H II Reg…

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This paper represents the conclusion of a project that had two main goals: (1) to investigate to what extent planetary nebulae (PNe) are chemically homogeneous; and (2) to provide physical constraints on the central star properties of each…

We compile published spectroscopic data and [O III] magnitudes of almost 500 extragalactic planetary nebulae (PNe) in 13 galaxies of various masses and morphological types. This is the first paper of a series that aims to analyze the PN…

Astrophysics of Galaxies · Physics 2020-09-09 Gloria Delgado-Inglada , Jorge García-Rojas , Grazyna Stasińska , Jackeline S. Rechy-García

In the first section we present the atomic part where a C2+ atomic target was prepared and used to generate theoretical data to investigate recombination lines arising from electron-ion collisions in thin plasma. R-matrix method was used to…

Atomic Physics · Physics 2012-11-07 Taha Sochi

In the last decade, ground-based Imaging Atmospheric Cherenkov Telescopes have discovered about 175 very-high-energy (VHE; $E >$ 100 GeV) gamma-ray sources, with more to follow with the development of H.E.S.S. II and CTA. Nearly 40 of these…

High Energy Astrophysical Phenomena · Physics 2018-02-02 Carlo van Rensburg , Christo Venter , Paulus Kruger

We study the oxygen abundance in five H II regions and seven planetary nebulae (PNe) located within 2 kpc from the Sun that have available spectra of high quality. Our analysis uses a similar procedure and the same atomic data to derive…

Astrophysics of Galaxies · Physics 2011-03-17 Mónica Rodríguez , Gloria Delgado-Inglada

Planetary nebulae (PNe) provide tests of stellar evolution, can serve as tracers of chemical evolution in the Milky Way and other galaxies, and are also used as a calibrator of the cosmological distance ladder. Current and upcoming large…

Solar and Stellar Astrophysics · Physics 2019-07-10 George Vejar , Rodolfo Montez , Margaret Morris , Keivan G. Stassun

In this paper we present fully reduced and dereddened emission line strengths for a sample of 45 southern Type II planetary nebulae (PNe). The spectrophotometry for these PNe covers an extended optical/near-IR range from 3600 - 9600…

Astrophysics · Physics 2009-11-07 J. B. Milingo , K. B. Kwitter , R. B. C. Henry , R. E. Cohen

Binary central stars have long been invoked to explain the vexing shapes of planetary nebulae (PNe) despite there being scant direct evidence to support this hypothesis. Modern large-scale surveys and improved observing strategies have…

Solar and Stellar Astrophysics · Physics 2015-05-30 Brent Miszalski

I explore the effects of observational errors on nebular chemical abundances using a sample of 179 optical spectra of 42 planetary nebulae (PNe) observed by different authors. The spectra are analysed in a homogeneous way to derive physical…

Astrophysics of Galaxies · Physics 2020-05-27 Mónica Rodríguez

Atomic physics techniques for the determination of ground-state properties of radioactive isotopes are very sensitive and provide accurate masses, binding energies, Q-values, charge radii, spins, and electromagnetic moments. Many fields in…

Atomic Physics · Physics 2015-06-11 Klaus Blaum , Jens Dilling , Wilfried Nörtershäuser

We present 2 to 2.4 micron integral field spectroscopy of a sample of hot post-AGB stars with early-B spectral types, using the NIFS instrument on Gemini North. These stars are just beginning to ionize their immediate environments and turn…

Solar and Stellar Astrophysics · Physics 2015-06-23 T. M. Gledhill , K. P. Forde

The interest to perform laser spectroscopy in the heaviest elements arises from the strong impact of relativistic effects, electron correlations and quantum electrodynamics on their atomic structure. Once this atomic structure is well…

Atomic Physics · Physics 2020-10-23 Michael Block , Mustapha Laatiaoui , Sebastian Raeder

PyNeb is a Python package widely used to model emission lines in gaseous nebulae. We take advantage of its object-oriented architecture, class methods, and historical atomic database to structure a practical environment for atomic data…

Planetary nebulae (PNe) can be roughly categorized into several broad morphological classes. The high quality images of PNe acquired in recent years, however, have revealed a wealth of fine structures that preclude simplistic models for…

Solar and Stellar Astrophysics · Physics 2015-05-18 L. F. Miranda , G. Ramos-Larios , M. A. Guerrero

The emission spectra and the ionization structure of the low ionization stages of iron, Fe I--IV, in gaseous nebulae are studied. This work includes: (i) new atomic data: photoionization cross sections, total e-ion recombination rates,…

Astrophysics · Physics 2009-10-30 Manuel A. Bautista , Anil K. Pradhan

Optical spectroscopy constitutes the historical path to accumulate basic knowledge on the atom and its structure. Former work based on fluorescence and resonance ionization spectroscopy enabled identifying optical spectral lines up to…

Atomic Physics · Physics 2020-07-14 Mustapha Laatiaoui , Alexei A. Buchachenko , Larry A. Viehland

In this contribution, I will briefly review the development of the theory of photoionized gaseous nebulae, highlighting some of the key events. I will then present some recent developments of deep spectroscopy of planetary nebulae (PNe) and…

Astrophysics of Galaxies · Physics 2010-02-23 Xiaowei Liu

We present the results of a near-infrared narrowband imaging survey of planetary nebulae. Objects were selected in a way that complements similar surveys done at visible and near-infrared wavelengths. No new detections of molecular hydrogen…

Astrophysics · Physics 2009-10-28 William B. Latter , Douglas M. Kelly , Joseph L. Hora , Lynne K. Deutsch

New ground-based telescopes and instruments, the return of the NICMOS instrument on the Hubble Space Telescope (HST), and the recent launch of the Spitzer Space Telescope have provided new tools that are being utilized in the study of…

Astrophysics · Physics 2009-11-11 Joseph L. Hora

Among all nuclear ground-state properties, atomic masses are highly specific for each particular combination of N and Z and the data obtained apply to a variety of physics topics. One of the most crucial questions to be addressed in mass…

Astrophysics · Physics 2008-12-10 Christine Weber , Klaus Blaum , Hendrik Schatz