Abstract Details

Name: Arun Roy
Affiliation: CHRIST (Deemed to be University), Bangalore
Conference ID: ASI2020_118
Title : PAH emission in Herbig Ae/Be Stars: A Spitzer view
Authors and Co-Authors : Arun Roy, Blesson Mathew, P. Manoj, Mayank Narang
Abstract Type : Oral
Abstract Category : Stars, ISM and Galaxy
Abstract : Herbig Ae/Be stars are intermediate mass pre-main sequence stars that are actively accreting matter from the protoplanetary disk. The disk contains gas and dust, which includes Carbonates, Silicates and large chain hydrocarbons called Polycyclic Aromatic Hydrocarbons (PAHs). Ultraviolet photons excite the PAH molecules and the molecule de-excites through different bending and stretching modes, emitting in mid-infrared. Thus mid-infrared spectra of a considerable fraction of Herbig Ae/Be stars are populated by various PAH features at 6.2, 7.7, 8.6, 11.2, and 12.7 μm. We compiled low-resolution mid-infrared spectra of 95 Herbig Ae/Be stars from the Spitzer space telescope archive. We classified the sample of Herbig Ae/Be stars into four categories based on the presence of PAH and Silicate emission features. We analyzed the mechanisms for the formation and destruction of PAH molecules from the correlation studies of PAH feature intensities/central wavelength with star/disk parameters such as stellar mass, mass accretion rate, and infrared excess. Also, we assessed the possibility of using these solid-state features to distinguish between the disk accretion process in early and late Herbig Ae/Be stars.