Related papers: Are fulleranes responsible for the 21 micron featu…
We compare and analyze the Spitzer mid-infrared spectrum of three fullerene-rich planetary nebulae in the Milky Way and the Magellanic Clouds; Tc1, SMP SMC16, and SMP LMC56. The three planetary nebulae share many spectroscopic similarities.…
The infrared (IR) spectra of many evolved carbon-rich stars exhibit two prominent dust emission features peaking around 21um and 30um, with the former exclusively seen in proto-planetary nebulae (PPNe), while the latter seen in a much wider…
Several planetary nebulae (PNe) have been found to contain both polycyclic aromatic hydrocarbon (PAH-like) species and fullerenes (C$_{60}$) distinguished by their mid-infrared emission. Previous laboratory and astronomical studies suggest…
Recent Spitzer Space Telescope observations of several astrophysical environments such as Planetary Nebulae, Reflection Nebulae, and R Coronae Borealis stars show the simultaneous presence of mid-infrared features attributed to neutral…
Emission of fullerenes in their infrared vibrational bands has been detected in space near hot stars. The proposed attribution of the diffuse interstellar bands at 9577 and 9632 \AA\ to electronic transitions of the buckminsterfullerene…
The high interstellar abundances of polycyclic aromatic hydrocarbons (PAHs) and their size distribution are the result of complex chemical processes implying dust, UV radiation, and the main gaseous components (H, C+, and O). These…
It is well known since 2010 that fullerene C60 is widespread through the interstellar space. Also, it is well known that graphene is a source material for synthesizing fullerene. Here, we simply assume the occurrence of graphene in space.…
We present high-resolution (R~15000) VLT/UVES optical spectra of two planetary nebulae (PNe; Tc 1 and M 1-20) where C60 (and C70) fullerenes have already been found. These spectra are of high-quality (S/N > 300) for PN Tc 1, which permits…
The origin of the so-called "21 micron" feature which is especially prominent in the spectra of some carbon-rich protoplanetary nebulae (PPNe}) is the matter of a lively debate. A large number of potential band carriers have been presented…
Although fullerenes have long been hypothesized to occur in interstellar environments, their actual unambiguous spectroscopic identification is of more recent date. C60, C70 and C60+ now constitute the largest molecular species individually…
Among its great findings, the IRAS mission showed the existence of an unidentified mid-IR feature around 21 um. Since its discovery, this feature has been detected in all C-rich proto-PNe of intermediate spectral type (A-G) and - weakly -…
We analyze the 11.2 {\mu}m unidentified infrared band (UIR) spectrum from NGC 7027 and identify a small fullerene (C24) as a plausible carrier. The blurring effects of lifetime and vibrational anharmonicity broadening obscure the narrower,…
Infrared spectra of carbon-rich objects which have evolved off the asymptotic giant branch reveal a range of dust properties, including fullerenes, polycyclic aromatic hydrocarbons (PAHs), aliphatic hydrocarbons, and several unidentified…
Fullerenes are a particularly stable class of carbon molecules in the shape of a hollow sphere or ellipsoid that might be formed in the outflows of carbon stars. Once injected into the interstellar medium (ISM), these stable species survive…
We present the detection of fullerenes C60 and C70 in the star-forming region IC 348 of the Perseus molecular cloud. Mid-IR vibrational transitions of C60 and C70 in emission are found in Spitzer IRS spectra of individual stars (LRLL 1, 2,…
The main goal of this thesis is to unveil some questions related to the formation of complex fullerene-based molecules in space, with the aim of resolving some key problems in astrophysics. The unexpected detections of fullerenes and…
The mysterious "21 micrometer" emission feature seen almost exclusively in the short-lived protoplanetary nebula (PPN) phase of stellar evolution remains unidentified since its discovery two decades ago. This feature is always accompanied…
We performed multiwavelength observations of the young planetary nebula (PN) M1-11 and obtained its elemental abundances, dust mass, and the evolutionary status of the central star. The AKARI/IRC, VLT/VISIR, and Spitzer/IRS spectra show…
The recent infrared detection of fullerenes (C60 and C70) in Planetary Nebulae (PNe) and R Coronae Borealis (RCB) stars offers a beautiful opportunity for studying the diffuse interstellar bands (DIBs) in sources where fullerenes are…
It has been more than 30 years since the enigmatic 21 {\mu}m emission feature was first discovered in protoplanetary nebulae (PPNs). Although dozens of different dust carrier candidates have been proposed, there is as yet no widely accepted…