Related papers: PAH emission from Herbig AeBe stars

Emission from a class of benzene-based molecules known as Polycyclic Aromatic Hydrocarbons (PAHs) dominates the infrared spectrum of star-forming regions. The observed emission appears to arise from the combined emission of numerous PAH…

Early Herbig Be (HBe) stars are massive, young stars accreting through the Boundary Layer mechanism. However, given the rapid ($<$ 2 Myr) evolution of early Herbig stars to the main-sequence phase, studying the evolution of the…

We measure IRAC colors of extended emission in several fields covering a range of Galactic latitudes and longitudes outside of star forming regions. We determine the nature of the Galactic diffuse emission in Spitzer/IRAC images by…

Using a large collection of near-infrared spectra (2.5-5.4 um) of Galactic HII regions and HII region-like objects, we perform a systematic investigation of the astronomical polycyclic aromatic hydrocarbon (PAH) features. 36 objects were…

Herbig Ae stars (HAe) are the precursors of Vega-type systems and, therefore, crucial objects in planet formation studies. Thus far, only a few disks associated with HAe stars have been studied using millimetre interferometers. Our aim is…

We present mid-infrared to optical properties of 22 representative irregular galaxies: 18 Im, 3 BCDs, and one Sm. The mid-IR is based on images from the Spitzer Space Telescope archives. The 3.6 and 4.5 micron bands and the UBVJHK images…

We present an analysis of the mid-infrared spectra, obtained from the Spitzer Space Telescope, of the dark globule, DC 314.8--5.1, which is at the onset of low-mass star formation. The target has a serendipitous association with a B-type…

The unidentified infrared emission (UIE) features at 3.3, 6.2, 7.7, 8.6, and 11.3 micrometer, commonly attributed to polycyclic aromatic hydrocarbon (PAH) molecules, have been recently ascribed to coal- or kerogen-like organic nanoparticles…

We examine polycyclic aromatic hydrocarbon (PAH), dust and atomic/molecular emission toward the Galactic bulge using Spitzer Space Telescope observations of four fields: C32, C35, OGLE and NGC 6522. These fields are approximately centered…

The PAH family of organic compounds (polycyclic aromatic hydrocarbons), involved in several fields of chemistry, has received particular attention in astrochemistry, where their vibrational spectroscopy, thermodynamic, dynamic, and…

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…

Polycyclic Aromatic Hydrocarbons (PAHs) have been detected throughout the universe where they play essential roles in the evolution of their environments. For example, they are believed to affect atmospheric loss rates of close-in planets…

We have carried out a photometric time domain study of 188 intermediate-mass young stars observed in Full Frame Image mode with the TESS satellite over the first 3.3 years of its mission. The majority of these targets are classified as…

We study the polarized infrared emission by Polycyclic Aromatic Hydrocarbons (PAHs), when anisotropically illuminated by UV photons. PAH molecules are modeled as planar disks with in-plane and out-of-plane vibrational dipoles. As first…

We completed a search for circumstellar disks around Herbig Be stars using the NRAO Very Large Array (VLA) and the IRAM Plateau de Bure (PdB) interferometers. We present our new VLA and PdBI data for the three objects MWC 297, Z CMa, and…

Recent observations have shown the presence of dust and molecular material in galactic winds, but relatively little is known about the distribution of these outflow components. To shed some light on this issue, we have used IRAC images from…

Polycyclic Aromatic Hydrocarbons (PAHs) are believed to be the small-size tail of the interstellar carbonaceous dust grain population. Their vibrational emission is the most widely accepted source of the aromatic near-infrared features, and…

Using the Keck I telescope, we have obtained 11.7 micron and 18.7 micron images of the circumstellar dust emission from AB Aur, a Herbig Ae star. We find that AB Aur is probably resolved at 18.7 micron with an angular diameter of 1.2" at a…

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

Herbig Ae/Be stars are young contracting stars on the radiative track in the HR diagram on their way to the main sequence. These stars provide a valuable link between high and low mass stars. Here we review the progress that has been made…