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相关论文: Positron Annihilation on Polycyclic Aromatic Hydro…

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As images and spectra from ISO and Spitzer have provided increasingly higher-fidelity representations of the mid-infrared (MIR) and Polycyclic Aromatic Hydrocarbon (PAH) emission from galaxies and galactic and extra-galactic regions, more…

宇宙学与河外天体物理 · 物理学 2015-05-20 Daniela Calzetti

The infrared signatures of polycyclic aromatic hydrocarbons (PAHs) are observed in a variety of astrophysical objects, including the circumnuclear medium of active galactic nuclei (AGNs). These are sources of highly energetic photons (0.2…

We report the results of a search for emission features from interstellar deuterated polycyclic aromatic hydrocarbons (PAHs) in the 4um region with the Infrared Camera (IRC) onboard AKARI. No significant excess emission is seen in 4.3-4.7um…

星系天体物理 · 物理学 2015-06-17 Takashi Onaka , Tamami I. Mori , Itsuki Sakon , Ryou Ohsawa , Hidehiro Kaneda , Yoko Okada , Masahiro Tanaka

Context: Polycyclic Aromatic Hydrocarbons, largely known as PAHs, are widespread in the universe and have been identified in a vast array of astronomical observations from the interstellar medium to protoplanetary discs. They are likely to…

地球与行星天体物理 · 物理学 2023-10-11 Dwaipayan Dubey , Fabian Grübel , Rosa Arenales-Lope , Karan Molaverdikhani , Barbara Ercolano , Christian Rab , Oliver Trapp

The exact nature of the 2175 Angstrom extinction bump, the strongest spectroscopic absorption feature superimposed on the interstellar extinction curve, remains unknown ever since its discovery in 1965. Popular candidate carriers for the…

星系天体物理 · 物理学 2023-08-10 Qi Lin , X. J. Yang , Aigen Li

Using physical models, we study the sensitivity of polycyclic aromatic hydrocarbon (PAH) emission spectra to the character of the illuminating starlight, to the PAH size distribution, and to the PAH charge distribution. Starlight models…

星系天体物理 · 物理学 2025-04-07 B. T. Draine , Aigen Li , Brandon S. Hensley , L. K. Hunt , K. Sandstrom , J. -D. T. Smith

Polycyclic Aromatic Hydrocarbons (PAHs) are carbon-based molecules resulting from the union of aromatic rings and related species, which are likely responsible for strong infrared emission features (3.3, 6.2, 7.7, 8.6, 11.3 and 12.7…

星系天体物理 · 物理学 2021-11-05 I. García-Bernete , D. Rigopoulou , A. Alonso-Herrero , M. Pereira-Santaella , P. F. Roche , B. Kerkeni

Polycyclic aromatic hydrocarbon (PAH) emission has long been proposed to be a potential star formation rate indicator, as it arises from the photodissociation region bordering the Str\"omgren sphere of young, massive stars. We apply a…

星系天体物理 · 物理学 2019-11-06 Yanxia Xie , Luis C. Ho

The high interstellar abundances of polycyclic aromatic hydrocarbons (PAHs) and their size distribution are the result of complex chemical processes implying dust, UV radiation, and the main gaseous components (H, C+, and O). These…

星系天体物理 · 物理学 2021-07-07 A. Omont , H. F. Bettinger

Aims. The chemistry of, and infrared (IR) emission from, polycyclic aromatic hydrocarbons (PAHs) in disks around Herbig Ae/Be and T Tauri stars are investigated. The equilibrium distribution of the PAHs over all accessible…

天体物理学 · 物理学 2009-11-13 R. Visser , V. C. Geers , C. P. Dullemond , J. -C. Augereau , K. M. Pontoppidan , E. F. van Dishoeck

The life cycle of the population of interstellar polycyclic aromatic hydrocarbon (PAH) molecules depends partly on the photostability of the individual species. We have studied the dissociative photoionization of two ethynyl-substituted PAH…

[Abridged] The ionization of polycyclic aromatic hydrocarbons (PAHs), by ultraviolet (UV) photons from massive stars is expected to account for a large fraction of the heating of neutral gas in galaxies. Evaluation of this proposal,…

星系天体物理 · 物理学 2022-12-14 O. Berné , S. Foschino , F. Jalabert , C. Joblin

We seek to understand the propagation mechanisms of positrons in the interstellar medium (ISM). This understanding is a key to determine whether the spatial distribution of the annihilation emission observed in our Galaxy reflects the…

高能天体物理现象 · 物理学 2015-05-14 P. Jean , W. Gillard , A. Marcowith , K. Ferrière

The integrated luminosity from the features of the polycyclic aromatic hydrocarbons (PAHs) exceeds the luminosity from atomic and molecular emission lines in the star-forming regions in galaxies and is a potential tracer of galaxy-scale…

Mixtures of polycylic aromatic hydrocarbons (PAHs) have been produced by means of laser pyrolysis. The main fraction of the extracted PAHs were primarily medium-sized, up to a maximum size of 38 carbon atoms per molecule. The use of…

天体物理仪器与方法 · 物理学 2011-01-24 M. Steglich , C. Jäger , G. Rouillé , F. Huisken , H. Mutschke , Th. Henning

Polycyclic aromatic hydrocarbons (PAHs) are among the most ubiquitous compounds in the universe, accounting for up to ~25% of all interstellar carbon. Since most unsubstituted PAHs do not possess permanent dipole moments, they are invisible…

Polycyclic aromatic hydrocarbons (PAHs) appear to be ubiquitous in terrestrial atmosphere as well as in the interstellar medium (ISM). In the astrophysical context presence of PAHs is interpreted by the observations of mid-IR emission bands…

化学物理 · 物理学 2019-03-26 Rashmi Singh , Shantanu Rastogi

We study the Polycyclic Aromatic Hydrocarbons (PAH) bands, ionic emission lines, and Mid-infrared continuum properties, in a sample of 171 emission line galaxies taken from literature plus 15 new active galactic nuclei (AGN) Spitzer…

宇宙学与河外天体物理 · 物理学 2015-05-20 Dinalva A. Sales , M. G. Pastoriza , R. Riffel

Polarized infrared emission from polycyclic aromatic hydrocarbons (PAHs) is important for testing the basic physics of alignment of ultrasmall grains and potentially offers a new way to trace magnetic fields. In this paper, a new model of…

星系天体物理 · 物理学 2017-12-15 Thiem Hoang

Using the AKARI, Wide-field Infrared Survey Explorer (WISE), Infrared Astronomical Satellite (IRAS), Sloan Digital Sky Survey (SDSS) and Hubble Space Telescope (HST) data, we investigated the relation of polycyclic aromatic hydrocarbon…