English
Related papers

Related papers: Polycyclic aromatic hydrocarbons with SPICA

200 papers

NGC 7023 is a well-studied reflection nebula, which shows strong emission from polycyclic aromatic hydrocarbon (PAH) molecules in the form of aromatic infrared bands (AIBs). The spectral variations of the AIBs in this region are connected…

Astrophysics of Galaxies · Physics 2016-05-25 B. A. Croiset , A. Candian , O. Berné , A. G. G. M. Tielens

We introduce a prescription for estimating the flux of the 7.7 micron and 11.3 micron\ polycyclic aromatic hydrocarbon (PAH) features from broadband JWST/MIRI images. Probing PAH flux with MIRI imaging data has advantages in field of view,…

We show the feasibility of spectroscopic cosmological surveys with the SAFARI instrument onboard of SPICA. The work is done through simulations that make use of both empirical methods, i.e. the use of observed luminosity functions and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 L. Spinoglio , M. Magliocchetti , S. Tommasin , A. M. Di Giorgio , C. Gruppioni , G. De Zotti , A. Franceschini , M. Vaccari , K. Isaak , F. Pozzi , M. A. Malkan

We design and train a neural network (NN) model to efficiently predict the infrared spectra of interstellar polycyclic aromatic hydrocarbons (PAHs) with a computational cost many orders of magnitude lower than what a first-principles…

Astrophysics of Galaxies · Physics 2020-10-20 Peter Kovacs , Xiaosi Zhu , Jesus Carrete , Georg K. H. Madsen , Zhao Wang

The formation of Polycyclic Aromatic Hydrocarbons in the circumstellar outflows of evolved stars is reviewed, with an emphasis on carbon stars on the Asymptotic Giant Branch. Evidence for PAHs present in their winds is provided by…

Solar and Stellar Astrophysics · Physics 2015-05-20 Isabelle Cherchneff

We explore indirect methods to detect Polycyclic Aromatic Hydrocarbons (PAHs) in gas-rich, absorption-selected galaxies at high redshift. We look at the optical VLT/X-shooter observations of an intervening, extremely strong damped…

Astrophysics of Galaxies · Physics 2022-06-22 Gargi Shaw , A. Ranjan

We use deep Spitzer mid-infrared spectroscopic maps of radial strips across three nearby galaxies with well-studied metallicity gradients (M101, NGC 628, and NGC 2403) to explore the physical origins of the observed deficit of polycyclic…

In order to find out capable molecular source of astronomically well observed infrared (IR) spectrum, asymmetric molecular configuration polycyclic aromatic hydrocarbon (PAH) was analyzed by the density functional theory (DFT) analysis.…

Astrophysics of Galaxies · Physics 2015-10-27 Norio Ota

Polycyclic Aromatic Hydrocarbons (PAHs) are widely accepted as the carriers of the Aromatic Infrared Bands (AIBs), but an unambiguous identification of any specific interstellar PAH is still missing. For polar PAHs, pure rotational…

Infrared emission features at 3.3, 6.2, 7.7, 8.6, and 11.2 $\mu$m, attributed to polycyclic aromatic hydrocarbons, show variations in relative intensity, shape, and peak position. These variations depend on the physical conditions of the…

Astrophysics of Galaxies · Physics 2021-11-24 C. Knight , E. Peeters , M. Wolfire , D. J. Stock

Following the tentative identification of the blue luminescence in the Red Rectangle by Vijh et al. (2005), we compute absolute fluxes for the vibrational IR emission and phosphorescence bands of three small polycyclic aromatic…

Astrophysics · Physics 2009-11-11 G. Mulas , G. Malloci , C. Joblin , D. Toublanc

The mid-infrared (MIR) spectra of dense photodissociation regions (PDRs) are typically dominated by emission from polycyclic aromatic hydrocarbons (PAHs) and the lowest pure rotational states of molecular hydrogen (H2); two species which…

Astrophysics of Galaxies · Physics 2011-02-09 Brian T. Fleming , Kevin France , Roxana E. Lupu , Stephan R. McCandliss

Interstellar Polycyclic Aromatic Hydrocarbon (PAH) molecules exist in diverse forms depending on the local physical environment. Formation of ionized PAHs (anions and cations) is favourable in the extreme conditions of the ISM. Besides in…

Astrophysics of Galaxies · Physics 2017-12-27 Mridusmita Buragohain , Amit Pathak , Peter Sarre , Nand Kishor Gour

Nuclear Magnetic Resonance (NMR) is one of the most powerful experimental techniques to characterize the structure of molecules and confined liquids. Nevertheless, the complexity of the systems under investigation usually requires…

We have conducted a sensitivity analysis on the mid-infrared spectral decomposition of galaxies and the modeling of the PAH emission spectrum with the NASA Ames PAH Infrared Spectroscopic Database (PAHdb) to assess the variance on the…

Recurrent fluorescence (RF) is an important relaxation mechanism in polycyclic aromatic hydrocarbons (PAHs), which could stabilize them and contribute to the production of aromatic infrared bands that are observed in the infrared spectra of…

Chemical Physics · Physics 2026-04-01 Damien Borja , Florent Calvo , Pascal Parneix , Cyril Falvo

A gas-phase optical spectrum of a large polycyclic aromatic hydrocarbon (PAH) cation - C78H26 +- in the 410-610 nm range is presented. This large all-benzenoid PAH should be large enough to be stable with respect to photodissociation in the…

Instrumentation and Methods for Astrophysics · Physics 2015-12-04 Junfeng Zhen , Giacomo Mulas , Anthony Bonnamy , Christine Joblin

We study the modifications on the ground and excited state properties of polycyclic aromatic hydrocarbons (PAHs), induced by the variation of concavity and $\pi$-connectivity. Inspired by experimentally feasible systems, we study three…

Mesoscale and Nanoscale Physics · Physics 2015-02-26 Caterina Cocchi , Deborah Prezzi , Alice Ruini , Marilia J. Caldas , Annalisa Fasolino , Elisa Molinari

The JWST will deliver large data sets of high-quality spectral data over the 0.6-28 $\mu$m range. It will combine sensitivity, spectral and spatial resolution. Specific tools are required to provide efficient scientific analysis of such…

Astrophysics of Galaxies · Physics 2019-12-11 Sacha Foschino , Olivier Berné , Christine Joblin

The cosmic-ray ionization rate ($\zeta$, s$^{-1}$) plays an important role in the interstellar medium. It controls ion-molecular chemistry and provides a source of heating. Here we perform a grid of calculations using the spectral synthesis…

Astrophysics of Galaxies · Physics 2021-01-13 Gargi Shaw , G. J. Ferland
‹ Prev 1 8 9 10 Next ›