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Related papers: The Mid-Infrared [SIV]/[NeII] versus [NeIII]/[NeII…

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The most important cooling lines of the neutral interstellar medium (ISM) lie in the far-infrared (FIR). We present measurements by the Infrared Space Observatory Long Wavelength Spectrometer of seven lines from neutral and ionized ISM of…

We present infrared spectroscopy from the Spitzer Space Telescope at one disk position and two positions at a height of 1 kpc from the disk in the edge-on spiral NGC 891, with the primary goal of studying halo ionization. Our main result is…

Astrophysics · Physics 2009-11-13 Richard J. Rand , Kenneth Wood , Robert A. Benjamin

Mid-infrared astronomy (operating at wavelengths ranging from 2 to 25 $\mu$m) has progressed significantly in the last decades, thanks to the improvement of detector techniques and the growing diameter of telescopes. Space observatories…

Instrumentation and Methods for Astrophysics · Physics 2011-06-16 O. Berne , A. G. G. M. Tielens , P. Pilleri , C. Joblin

The flux and line shape of the fine-structure transitions of \NeII\ and \NeIII\ at 12.8 and 15.55\,$\mu$m and of the forbidden transitions of \OI\ $\lambda6300$ are calculated for young stellar objects with a range of mass-loss rates and…

Solar and Stellar Astrophysics · Physics 2010-04-29 Hsien Shang , Alfred Glassgold , Wei-Chieh Lin , Chun-Fan J. Liu

The [CII] 157.74 $\mu$m fine structure transition is one of the brightest and most well-studied emission lines in the far-infrared (FIR), produced in the interstellar medium (ISM) of galaxies. We study its properties in sub-pc resolution…

Astrophysics of Galaxies · Physics 2024-03-05 Alon Gurman , Chia-Yu Hu , Amiel Sternberg , Ewine F. van Dishoeck

The [CII] $158\,\mu\mathrm{m}$ fine-structure line is one of the dominant coolants of the neutral interstellar medium. It is hence one of the brightest far-infrared emission lines and can be observed not only in star-forming regions…

(Abridged) We examine standard methods of measuring nebular chemical abundances, including estimates based on direct T_e measurements, and also bright-line diagnostics. We use observations of 4 LMC HII regions whose ionizing stars have…

Astrophysics · Physics 2009-10-31 M. S. Oey , J. C. Shields

Spectrophotometry constitutes a unique way to obtain the whole diagnostics (density, temperature, ionic abundances) of ionized gas nebulae, thus providing invaluable information about the objects where they reside. If such nebulae are in…

Astrophysics · Physics 2007-05-23 E. Perez-Montero , A. I. Diaz

We employ ionization-parameter mapping (IPM) to infer the optical depth of HII regions in the northern half of M33. We construct [OIII]$\lambda 5007$/[OII]$\lambda 3727$ and [OIII]$\lambda 5007$/[SII]$\lambda 6724$ ratio maps from…

Astrophysics of Galaxies · Physics 2021-12-22 Amit N. Sawant , Eric W. Pellegrini , M. S. Oey , Jesús López-Hernández , Genoveva Micheva

Nebular emission lines are critical to measure physical properties in the ionized gas (e.g., metallicity, the SFR, or dust attenuation). They also account for a significant fraction of broadband fluxes, in particular at the highest…

Astrophysics of Galaxies · Physics 2020-01-08 Fang-Ting Yuan , Denis Burgarella , David Corre , Veronique Buat , Médéric Boquien , Shiyin Shen

We present new Spitzer Space Telescope data on the nearby, low-metallicity starburst galaxy NGC 5253, from the Infrared Array Camera IRAC and the Infrared Spectrograph IRS. The mid-IR luminosity profile of NGC 5253 is clearly dominated by…

Astrophysics · Physics 2009-11-11 P. Beirao , B. R. Brandl , D. Devost , J. D. Smith , L. Hao , J. R. Houck

We analyzed high-resolution mid-infrared spectra of 78 well-known Herbig Ae/Be (HAeBe) stars using Spitzer InfraRed Spectrograph data, focusing on the detection of [Ne {\sc II}] and [Ne {\sc III}] emission lines as indicators of ionized…

Solar and Stellar Astrophysics · Physics 2025-06-03 D. Akhila , Blesson Mathew , S. Nidhi , B. Shridharan , R. Arun , Hema Anilkumar , G. Maheswar , Sreeja S. Kartha , P. Manoj , Suman Bhattacharyya

From ISO [Ne V] 14.3/24.3 micron line flux ratios, we find that 10 out of 20 planetary nebulae (PNs) have measured ratios below the low-electron density (N_e) theoretical predicted limit. Such astronomical data serve to provide important…

Astrophysics · Physics 2007-05-23 R. H. Rubin

The origin of the observed variability of the gas-phase D/H ratio in the local interstellar medium is still debated, and in particular the role of deuterium depletion onto dust grains. Here we extend the study of the relationship between…

Astrophysics · Physics 2009-11-13 R. Lallement , G. Hebrard , B. Y. Welsh

We analyse mid-infrared (MIR) spectroscopic properties for 19 ultra-luminous infrared quasars (IR QSOs) in the local universe based on the spectra from the Infrared Spectrograph on board the Spitzer Space Telescope. The MIR properties of IR…

Astrophysics · Physics 2009-11-13 Chen Cao , X. Y. Xia , Hong Wu , S. Mao , C. N. Hao , Z. G. Deng

The ratio of the [CII] 158$\,\mu$m emission line over the total infrared emission (TIR) is often used as a proxy for the photoelectric (PE) heating efficiency ($\epsilon_{\rm PE}$) of the far-ultraviolet (FUV) photons absorbed by dust in…

We present near-infrared synthetic spectra of a delayed-detonation hydrodynamical model and compare them to observed spectra of four normal type Ia supernovae ranging from day +56.5 to day +85. This is the epoch during which supernovae are…

Solar and Stellar Astrophysics · Physics 2015-06-22 Brian Friesen , E. Baron , John P. Wisniewski , Jerod T. Parrent , R. C. Thomas , Timothy R. Miller , G. H. Marion

Context. The properties of dust grains, in particular their size distribution, are expected to differ from the interstellar medium to the high-density regions within molecular clouds. Aims. We measure the mid-infrared extinction law…

Astrophysics of Galaxies · Physics 2015-06-12 J. Ascenso , C. J. Lada , J. Alves , C. G. Román-Zúñiga , M. Lombardi

SNe Ia are good distance indicators because the shape of their light curves, which can be measured independently of distance, varies smoothly with luminosity. This suggests that SNe Ia are a single family of events. Similar correlations are…

We present results from the Spitzer/IRS spectral mapping observations of 15 local luminous infrared galaxies (LIRGs). In this paper we investigate the spatial variations of the mid-IR emission which includes: fine structure lines, molecular…

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