Related papers: The PAH hypothesis after 25 years

The near- and mid-IR spectrum of many astronomical objects is dominated by emission bands due to UV-excited polycyclic aromatic hydrocarbons (PAH) and evaporating very small grains (eVSG). Previous studies with the ISO, Spitzer and AKARI…

We have obtained ISOPHOT-S low resolution mid-infrared spectra of a sample of 60 Ultraluminous Infrared Galaxies (ULIRGs). We use the strength of the `PAH' mid-infrared features as a discriminator between starburst and AGN activity, and to…

Interstellar polycyclic aromatic hydrocarbon (PAHs) are an important component of the interstellar medium of galaxies, containing some 10 percent of the elemental carbon. Their vibrational emission dominates the mid-infrared spectra of…

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…

Polycyclic aromatic hydrocarbon (PAH) emission has been found in both starbursts and modestly starforming galaxies, but the relation between starforming activity and PAH luminosity is still a matter of debate. The different correlation…

Based on theoretical spectra computed using Density Functional Theory we study the properties of Polycyclic Aromatic Hydrocarbons (PAH). In particular using bin-average spectra of PAH molecules with varying number of carbons we investigate…

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…

We report the first results of a low resolution mid-infrared spectroscopic survey of an unbiased, far-infrared selected sample of 60 ultraluminous infrared galaxies, using ISOPHOT-S on board ISO. We use the ratio of the 7.7um `PAH' emission…

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…

Polycyclic Aromatic Hydrocarbon (PAH) emission features dominate the mid-infrared spectra of star-forming galaxies and can be useful to calibrate star formation rates and diagnose ionized states of grains. However, the PAH 3.3 micron…

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…

The so-called "unidentified infrared emission" (UIE) features at 3.3, 6.2, 7.7, 8.6, and 11.3 micron ubiquitously seen in a wide variety of astrophysical regions are generally attributed to polycyclic aromatic hydrocarbon (PAH) molecules.…

We present the mid-infrared spectra of seven of the most powerful radio-galaxies known to exist at 1.5 < z < 2.6. The radio emission of these sources is dominated by the AGN with 500 MHz luminosities in the range 10^27.8 - 10^29.1 W/Hz. The…

Broad infrared emission features (e.g., at 3.3, 6.2, 7.7, 8.6, and 11.3 microns) from the gas phase interstellar medium have long been attributed to polycyclic aromatic hydrocarbons (PAHs). A significant portion (10%-20%) of the Milky Way's…

We investigate the mid-infrared (IR) emission in the Orion Bar photodissociation region, using archival photometric and spectroscopic observations from UKIRT, Spitzer, ISO, and SOFIA telescopes. Specifically, we consider flux densities of…

Using the Infrared Spectrograph on board the Spitzer Space Telescope, we present low-resolution (64 < lambda / dlambda < 124), mid-infrared (20-38 micron) spectra of 23 high-redshift ULIRGs detected in the Bootes field of the NOAO Deep…

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…

Infrared (IR) emission spectra are calculated for dust composed of mixtures of amorphous silicate and graphitic grains, including varying amounts of polycyclic aromatic hydrocarbon (PAH) particles. The models are constrained to reproduce…

The spatial distribution of 3.3 \mum PAH and associated emission in the 3.3" x 6.0" inner region of the Red Rectangle nebula has been determined using the UIST imager-spectrometer at the United Kingdom Infrared Telescope (UKIRT).…

We present a sample of low-resolution 5-38um Spitzer IRS spectra of the inner few square kiloparsecs of 59 nearby galaxies spanning a large range of star formation properties. A robust method for decomposing mid-infrared galaxy spectra is…