Related papers: Tracing PAH Emission in $\lambda$-Orionis Using CO…
We have examined polycyclic aromatic hydrocarbon (PAH) excitation in a sample of 25 nearby face-on spiral galaxies using the ratio of mid-infrared PAH emission to dust mass. Within 11 of the galaxies, we found that the PAH excitation was…
Photodissociation regions (PDRs) exhibit emission between 3-20 um known as the Aromatic Infrared Bands (AIBs), originating from small carbonaceous species such as polycyclic aromatic hydrocarbons (PAHs). The AIB spectra observed in Galactic…
The PAH model predicts many weak emission features in the 1-5 $\mu$m region that can resolve significant questions that it has faced since its inception in the mid-80s. These features contain fundamental information about the PAH population…
The so-called unidentified infrared emission (UIE) features at 3.3, 6.2, 7.7, 8.6, and 11.3 micrometer are ubiquitously seen in a wide variety of astrophysical regions. The UIE features are characteristic of the stretching and bending…
We present a new method to accurately describe the ionization fraction and the size distribution of polycyclic aromatic hydrocarbons (PAHs) within astrophysical sources. To this purpose, we have computed the mid-infrared emission spectra of…
Aims: We search for PAH features towards T Tauri stars and compare them with surveys of Herbig Ae/Be stars. The presence and strength of the PAH features are interpreted with disk radiative transfer models exploring the PAH feature…
The chemistry of astronomical hydrocarbons, responsible for the well-known infrared emission features detected in a wide variety of targets, remains enigmatic. Here we focus on the group of young intermediate-mass Herbig Ae stars. We have…
We observed four nearby spiral galaxies (NGC 3627, NGC 4254, NGC 4736 and NGC 5055) in the K band with the 64-m Sardinia Radio Telescope, with the aim of detecting the Anomalous Microwave Emission (AME), a radiation component presumably due…
We report long-slit spectroscopic observations of the Herbig Ae/Be star Elias 1 in the 3.2-3.6 mum region covering the C-H stretch emission features of hydrogen-terminated diamonds and PAHs. The data were recorded at UKIRT using UIST and…
Following our initial discovery of blue luminescence in the spectrum of the Red Rectangle (RR) and its identification as fluorescence by small three- to four-ringed polycyclic aromatic hydrocarbon (PAH) molecules, we report on the spatial…
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…
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…
We have used sensitive archival data from the Infrared Space Observatory (ISO) to make maps of the edge-on low SFR galaxy, NGC 5907, in 6 different MIR bands: LW2, LW5, LW6, LW7, LW8, and LW10, covering the spectrum from 6.5 to 15.0 microns…
The aromatic features in M101 were studied spectroscopically and photometrically using observations from all three instruments on the Spitzer Space Telescope. The global SED of M101 shows strong aromatic feature (commonly called PAH…
Polycyclic Aromatic Hydrocarbons (PAHs) are ubiquitous complex molecules in the interstellar medium and are used as an indirect indicator of star-formation. On the other hand the ultraviolet (UV) emission from the young massive stars…
We use JWST/NIRCam and MIRI imaging acquired by the Feedback in Emerging extrAgalactic Star clusTers (FEAST) program along with archival HST imaging to map ionized gas (Pa$\alpha$, Br$\alpha$, and H$\alpha$) and Polycyclic Aromatic…
We explore the relationships between the Polycyclic Aromatic Hydrocarbon (PAH) feature strengths, mid-infrared continuum luminosities, far-infrared spectral slopes, optical spectroscopic classifications, and silicate optical depths within a…
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…
Anomalous microwave emission (AME) has been observed in numerous sky regions, in the frequency range ~10-60 GHz. One of the most scrutinized regions is G159.6-18.5, located within the Perseus molecular complex. In this paper we present…
We present recent observations of small hydrocarbons (C3H2, C2H, C4H) with high abundances in the Photo-Dissociation Region of the Horsehead nebula. Our results show for the first time observational indications that the small hydrocarbon…