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Related papers: Infrared [Fe II] Emission Lines from Radiative Ato…

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Low-ionisation structures (LISs) are commonly found in planetary nebulae (PNe) but they are still poorly understood. The recent discovery of unforeseen molecular hydrogen gas (H2) has changed what we think we know about these…

Solar and Stellar Astrophysics · Physics 2025-07-11 Stavros Akras , Isabel Aleman , Denise R. Gonçalves , Gerardo Ramos-Larios , Konstantinos Bouvis

The late-time spectra of Type Ia supernovae (SNe Ia) are powerful probes of the underlying physics of their explosions. We investigate the late-time optical and near-infrared spectra of seven SNe Ia obtained at the VLT with XShooter at…

The Eddington ratio is a key parameter that governs the diversity of quasar properties. It can be scaled with a strong anti-correlation between optical Fe II and [O III] emission. In search of such indicators in the far-UV band, the HST…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-30 Wei Zheng

In this work we studied the two-dimensional ionization structure of the circumnuclear and extranuclear regions in a sample of six low-z Ultraluminous Infrared Galaxies using Integral Field Spectroscopy. The ionization conditions in the…

Astrophysics · Physics 2016-08-30 A. Monreal-Ibero , S. Arribas , L. Colina

Fe II emission is a well-known contributor to the UV spectra of active galactic nuclei and the modeling of this part may affect the results obtained for the MgII$\lambda2800$ emission, which is one of the lines used for black hole mass…

The centre of NGC 4151 has been observed in the J-band with the SMIRFS integral field unit (IFU) on the UK Infrared Telescope. A map of [Fe II] emission is derived, and compared with the distributions of the optical narrow line region and…

Emission lines that trace elements subject to strong depletion onto grains provide a means for probing the dust content of AGNs. Examples include infrared [FeII] and optical [CaII] lines. The excitation mechanisms underlying the [FeII]…

Astrophysics · Physics 2007-05-23 Joseph C. Shields , Richard W. Pogge , Michael M. De Robertis

The physical conditions in typical starburst galaxies are investigated through critical infrared (IR) line ratios, as previously suggested by Lutz et al. (1998, A&A, 333, L75). The calculations by a composite model which consistently…

Astrophysics · Physics 2007-05-23 Sueli M. Viegas , Marcella Contini , Thierry Contini

A detailed study of emission lines from Fe VII, Fe VIII and Fe IX observed by the EUV Imaging Spectrometer on board the Hinode satellite is presented. Spectra in the ranges 170-212 A and 246-292 A show strongly enhanced lines from the upper…

Solar and Stellar Astrophysics · Physics 2015-05-13 P. R. Young , E. Landi

This paper reports the results of a near infrared spectroscopic survey of LINER galaxies undertaken with a new infrared spectrograph at the 5 m Hale telescope. The galaxy sample includes 11 LINERs with spectra covering the [FeII] (1.2567…

Astrophysics · Physics 2009-10-30 J. E. Larkin , L. Armus , R. A. Knop , B. T. Soifer , K. Matthews

We investigate the diagnostic capabilities of the iron lines for tracing the physical conditions of the shock-excited gas in jets driven by pre-main sequence stars. We have analyzed the 300-2500 nm X-shooter spectra of two jets driven by…

Astrophysics of Galaxies · Physics 2015-06-17 T. Giannini , B. Nisini , S. Antoniucci , J. M. Alcala' , F. Bacciotti , R. Bonito , L. Podio , B. Stelzer , E. T. Whelan

Evolution of fast, radiative shocks in high density medium is presented. Ionizing spectra and approximate broad band light curves of the shocked gas are calculated. Emergent shock spectra, as seen by a distant observer, are obtained from…

Astrophysics · Physics 2015-06-24 Tomasz Plewa

We report the detection of [Ne II] emission at 12.81 micron in four out of the six optically thick dust disks observed as part of the FEPS Spitzer Legacy program. In addition, we detect a H I(7-6) emission line at 12.37 micron from the…

We obtained 0.8-2.4 micron spectra at a resolution of 320 km/s of four narrow-line Seyfert 1 galaxies in order to study the near-infrared properties of these objects. We focus on the analysis of the FeII emission in that region and the…

Astrophysics · Physics 2009-11-07 A. Rodriguez-Ardila , S. M. Viegas , M. G. Pastoriza , L. Prato

We review problems raised by Fe II emission in AGNs and address the question of its relationship to other broad-line region (BLR) lines. The self-shielding, stratified, BLR model of Gaskell, Klimek & Nazarova (2007; GKN) predicts that Fe II…

Astrophysics of Galaxies · Physics 2022-02-16 C. Martin Gaskell , Neha Thakur , Betsy Tian , Anjana Saravana

Coronal Mass Ejections (CMEs) are believed to be effective in producing shocks in the solar corona and the interplanetary space. One of the important signatures of shocks and shock acceleration are Type II solar radio bursts that drift with…

Solar and Stellar Astrophysics · Physics 2018-11-28 Nicolina Chrysaphi , Eduard P. Kontar , Gordon D. Holman , Manuela Temmer

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…

We report initial results from the far-infrared fine structure line observations of a sample of 44 local starbursts, Seyfert galaxies and infrared luminous galaxies obtained with the PACS spectrometer on board Herschel. We show that the…

The interstellar medium (ISM) consists of highly ionized and neutral atomic, as well as molecular, components. Knowledge of their distribution is important for tracing the structure and lifecycle of the ISM. Here we determine the properties…

Astrophysics of Galaxies · Physics 2016-05-25 W. D. Langer , P. F. Goldsmith , J. L. Pineda

We report 0.9-1.4 micron spectroscopic observations of NGC1068 collected during the commissioning phase of the near infrared camera spectrometer (NICS) of the Telescopio Nazionale Galileo (TNG). These yielded the first extragalactic…