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Related papers: Atomic data and the density structures of planetar…

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Nearly 30 years after the first detailed studies of low-ionization structures (LISs) in planetary nebulae (PNe), we perform a statistical analysis of their physical, chemical and excitation properties, by collecting published data in the…

Astrophysics of Galaxies · Physics 2023-08-10 M. Belén Mari , Stavros Akras , Denise R. Gonçalves

We demonstrate that the matter density distribution in the surface region is determined well by the use of the relatively low-intensity beams that become available at the upcoming radioactive beam facilities. Following the method used in…

Nuclear Theory · Physics 2009-11-07 Akihisa Kohama , Ryoichi Seki , Akito Arima , Shuhei Yamaji

Photoionization models frequently assume constant temperature or density within HII regions. We investigate this assumption by measuring the detailed temperature and density structures of four HII regions in the Large Magellanic Cloud and…

Astrophysics of Galaxies · Physics 2023-10-04 Yifei Jin , Ralph Sutherland , Lisa Kewley , David Nicholls

Deep spectrophotometry has proved to be a fundamental tool to improve our knowledge on the chemical content of planetary nebulae. With the arrival of very efficient spectrographs installed in the largest ground-based telescopes, outstanding…

Solar and Stellar Astrophysics · Physics 2016-12-15 Jorge García-Rojas

Planetary nebulae (PNe) have diverse morphological shapes, including point-symmetric and multipolar structures. Many PNe also have complicated internal structures such as torus, lobes, knots, and ansae. A complete accounting of all the…

Solar and Stellar Astrophysics · Physics 2012-11-20 Sze-Ning Chong , Sun Kwok , Hiroshi Imai , Daniel Tafoya , James Chibueze

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

The spatial structure of the emission lines and continuum over the 50 arcsecond extent of the nearby, O-rich, planetary nebula NGC 7009 (Saturn Nebula) have been observed with the MUSE integral field spectrograph on the ESO Very Large…

We have used the He I discontinuities at 3421A to determine the electron temperatures, designated Te(He I), for a sample of five Galactic planetary nebulae (PNe). We compared Te(He I) with the electron temperatures derived from the hydrogen…

Solar and Stellar Astrophysics · Physics 2011-02-11 Y. Zhang , H. -B. Yuan , C. -T. Hua , X. -W. Liu , J. Nakashima , S. Kwok

We explore oscillations of the solar $^8$B neutrinos in the Earth in detail. The relative excess of night $\nu_e$ events (the Night-Day asymmetry) is computed as function of the neutrino energy and the nadir angle $\eta$ of its trajectory.…

High Energy Physics - Phenomenology · Physics 2017-08-16 Ara Ioannisian , Alexei Yu. Smirnov , Daniel Wyler

We present MUSE deep integral-field unit spectroscopy of three planetary nebulae(PNe) with high abundance discrepancy factors (ADF > 20): NGC 6778, M 1-42 and Hf 2-2. We have constructed flux maps for more than 40 emission lines, and use…

This report summarizes laboratory measurements of atomic wavelengths, energy levels, hyperfine and isotope structure, energy level lifetimes, and oscillator strengths. Theoretical calculations of lifetimes and oscillator strengths are also…

Atomic Physics · Physics 2015-10-30 Gillian Nave , Sultana Nahar , Gang Zhao

The current need for atomic data to model stellar spectra obtained in various wavelength ranges is described. The level of completeness and accuracy of these data is discussed.

Instrumentation and Methods for Astrophysics · Physics 2015-10-01 R. Monier

{It is necessary to understand the dynamics of the atomic gas to use complex modeling and to carry out detailed comparisons between theoretical models and observations.}{In a companion paper, we present high resolution bidimensional…

Astrophysics · Physics 2007-05-23 P. Hennebelle , E. Audit , M. -A Miville-Deschenes

Neutron(n)-capture elements (atomic number Z>30), which can be produced in planetary nebula (PN) progenitor stars via s-process nucleosynthesis, have been detected in nearly 100 PNe. This demonstrates that nebular spectroscopy is a…

Solar and Stellar Astrophysics · Physics 2015-05-30 N. C. Sterling , M. C. Witthoeft , D. A. Esteves , P. C. Stancil , A. L. D. Kilcoyne , R. C. Bilodeau , A. Aguilar

We derive new self-consistent theoretical UV, optical, and IR diagnostics for the ISM pressure and electron density in the ionized nebulae of star-forming galaxies. Our UV diagnostics utilize the inter-combination, forbidden and resonance…

In this study, we present the results of photoionization modeling for 124 planetary nebulae (PNe) in the Galactic bulge. Utilizing the {\scshape cloudy} code, we derived the effective temperatures (T$_{eff}$) of the central stars, with a…

Astrophysics of Galaxies · Physics 2025-10-21 N. Aksaker , A. Demirci , N. Erzincan , A. Akyuz

In this paper we develop tools for observers to use when analysing nebular spectra for temperatures and metallicities, with two goals: to present a new, simple method to calculate equilibrium electron temperatures for collisionally excited…

Astrophysics of Galaxies · Physics 2013-07-18 David C. Nicholls , Michael A. Dopita , Ralph S. Sutherland , Lisa J. Kewley , Ethan Palay

We present spectroscopy of planetary nebulae in M32 and in the bulge of M31 that we obtained with the MOS spectrograph at the Canada-France-Hawaii Telescope. Our sample includes 30 planetary nebulae in M31 and 9 planetary nebulae in M32. We…

Astrophysics · Physics 2009-10-30 Michael G. Richer , Grazyna Stasinska , Marshall L. McCall

The information on the symmetry energy and its density dependence is deduced by comparing the available data on the electric dipole polarizability $\alpha_D$ of ${}^{68}$Ni, ${}^{120}$Sn, and ${}^{208}$Pb with the predictions of the Random…

Nuclear Theory · Physics 2015-12-10 X. Roca-Maza , X. Viñas , M. Centelles , B. K. Agrawal , G. Colo' , N. Paar , J. Piekarewicz , D. Vretenar

The Earth's density distribution can be approximately considered piecewise continuous at the scale of two-flavor oscillations of typical solar neutrinos, such as the beryllium-7 and boron-8 neutrinos. This quite general assumption appears…

High Energy Physics - Phenomenology · Physics 2013-03-01 S. S. Aleshin , O. G. Kharlanov , A. E. Lobanov
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