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Related papers: Predicted FeII Emission-Line Strengths from Active…

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We have recorded spectra of iron-neon and iron-argon hollow cathode lamps in the region 1700A -- 5um (59000 -- 2000cm-1), with Fourier transform (FT) spectrometers at the National Solar Observatory, Tucson, Arizona, U.S.A. and Imperial…

Astrophysics · Physics 2007-05-23 I. G. Nave , S. Johansson , R. C. M. Learner , A. P. Thorne , J. W. Brault

We report new statistical equilibrium calculations for Fe I and Fe II in the atmosphere of Late-Type stars. We used atomic models for Fe I and Fe II having respectively 256 and 190 levels, as well as 2117 and 3443 radiative transitions.…

Astrophysics · Physics 2016-08-30 F. Thevenin , T. P. Idiart

We present a coherent database of spectroscopic observations of far-IR fine-structure lines from the Herschel/PACS archive for a sample of 170 local AGN, plus a comparison sample of 20 starburst galaxies and 43 dwarf galaxies. Published…

Astrophysics of Galaxies · Physics 2016-10-19 J. A. Fernández-Ontiveros , L. Spinoglio , M. Pereira-Santaella , M. A. Malkan , P. Andreani , K. M. Dasyra

In order to examine how narrow emission-line flux ratios depend on the Seyfert type, we compiled various narrow emission-line flux ratios of 355 Seyfert galaxies from the literature. We present in this paper that the intensity of the…

Astrophysics · Physics 2015-06-24 Tohru Nagao , Takashi Murayama , Yoshiaki Taniguchi

[Fe II] emission lines are prominent in the infrared (IR), and they are important diagnostic tools for radiative atomic shocks. We investigate the emission characteristics of [Fe II] lines using a shock code developed by Raymond (1979) with…

Astrophysics of Galaxies · Physics 2016-07-20 Bon-Chul Koo , John C. Raymond , Hyun-Jeong Kim

The Breit-Pauli R-matrix method developed under the Iron Project has been used to obtain extensive sets of oscillator strengths and transition probabilities for dipole allowed and intercombination fine structure transitions in carbon like…

Astrophysics · Physics 2009-10-31 Sultana N. Nahar

We report on the spectroscopic study of 19 low luminosity Flat Radio Spectrum (LL FRS) sources selected from Marcha's et al. (1996) 200 mJy sample. In the optical, these objects are mainly dominated by the host galaxy starlight. After…

Astrophysics · Physics 2009-11-10 A. C. Goncalves , M. Serote Roos

The nebular spectra of Type Ia supernovae ($\gtrapprox$ 100 days after explosion) consist mainly of emission lines from singly- and doubly-ionised Fe-group nuclei. However, theoretical models for many scenarios predict that non-thermal…

High Energy Astrophysical Phenomena · Physics 2022-04-11 Luke J. Shingles , Andreas Flörs , Stuart A. Sim , Christine E. Collins , Friedrich K. Roepke , Ivo R. Seitenzahl , Ken J. Shen

We analyze the applicability of far-infrared fine-structure lines [CII] 158 micron, [OI] 63 micron and [OIII] 88 micron to reliably trace the star formation rate (SFR) in a sample of low-metallicity dwarf galaxies from the Herschel Dwarf…

With the purpose of assessing classic spectroscopic methods on high-resolution and high signal-to-noise ratio spectra in the near-infrared wavelength region, we selected a sample of 65 F-, G-, and K-type stars observed with CARMENES, the…

Radiative transfer calculations have predicted intensity enhancements for optically thick emission lines, as opposed to the normal intensity reductions, for astrophysical plasmas under certain conditions. In particular, the results are…

Solar and Stellar Astrophysics · Physics 2015-05-30 F. P. Keenan , D. J. Christian , S. J. Rose , M. Mathioudakis

We construct a 3D radiative-hydrodynamic model atmosphere of parameters Teff = 4820 K, log g = 4.5, and solar chemical composition. The theoretical line profiles computed with this model are asymmetric, with their bisectors having a…

Solar and Stellar Astrophysics · Physics 2015-05-13 I. Ramirez , C. Allende Prieto , L. Koesterke , D. L. Lambert , M. Asplund

X-ray spectra from stellar coronae are reprocessed by the underlying photosphere through scattering and photoionization events. While reprocessed X-ray spectra reaching a distant observer are at a flux level of only a few percent of that of…

Astrophysics · Physics 2009-11-13 Jeremy J. Drake , Barbara Ercolano , Douglas A. Swartz

We produce simulations of emission of the atomic CII line in large sky fields in order to determine the current prospects for mapping this line during the high redshift Epoch of Reionization. We estimate the CII line intensity, redshift…

Astrophysics of Galaxies · Physics 2015-05-22 Marta B. Silva , Mário G. santos , Asantha Cooray , Yan Gong

Stellar population models produce radiation fields that ionize oxygen up to O+2, defining the limit of standard HII region models (<54.9 eV). Yet, some extreme emission line galaxies, or EELGs, have surprisingly strong emission originating…

Astrophysics of Galaxies · Physics 2021-12-08 Danielle A. Berg , John Chisholm , Dawn K. Erb , Evan D. Skillman , Richard W. Pogge , Grace M. Olivier

The star Beta Pic is widely known for harbouring a large population of exocomets, which create variable absorption signatures in the stellar spectrum as they transit the star. While the physical and chemical properties of these objects have…

Earth and Planetary Astrophysics · Physics 2024-10-30 T. Vrignaud , A. Lecavelier des Etangs

Recent fully relativistic calculations of radiative rates and electron impact excitation cross sections for Fe {\sc xiii} are used to generate emission-line ratios involving 3s$^{2}$3p$^{2}$--3s3p$^{3}$ and 3s$^{2}$3p$^{2}$--3s$^{2}$3p3d…

Astrophysics · Physics 2008-11-26 F P Keenan , D B Jess , K M Aggarwal , R J Thomas , J W Brosius , J M Davila

We explore the kinematics of ionized gas via the [O III] $\lambda$5007 emission lines in active galactic nuclei (AGN) selected on the basis of their mid-infrared (IR) emission, and split into obscured and unobscured populations based on…

Astrophysics of Galaxies · Physics 2018-04-11 M. A. DiPompeo , R. C. Hickox , C. M. Carroll , J. C. Runnoe , J. R. Mullaney , T. C. Fischer

In order to perform a more complete census of active galactic nuclei (AGN) in the local Universe, we investigate the use of the HeII~$\lambda 4685$ emission line diagnostic diagram by Shirazi & Brinchmann (2012) in addition to the standard…

Astrophysics of Galaxies · Physics 2017-01-25 Rudolf Bär , Anna K. Weigel , Lia F. Sartori , Kyuseok Oh , Michael Koss , Kevin Schawinski

We present first realistic numerical simulations of 3D radiative convection in the surface layers of main sequence A-type stars with Teff = 8000 K and 8500 K, log g = 4.4 and 4.0, recently performed with the CO5BOLD radiation hydrodynamics…

Astrophysics · Physics 2007-05-23 M. Steffen , B. Freytag , H. -G. Ludwig
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