Activation of the 3.47 μm Band by H Atom Irradiation of Carbon Grains Covered with a Water Ice Layer at 12 K

Mennella, V.

doi:10.1086/591051

Cited by 23 publications

(35 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…and with the likely irradiation effects and the associated aliphatic to aromatic transformation in the ISM (e.g., Jones 1990; Dartois et al 2004a,b;Pino et al 2008;Mennella 2008;Godard et al 2011), in circumstellar regions (e.g., Goto et al 2003Goto et al , 2007Sloan et al 2007;Pino et al 2008), in interplanetary dust particles (IDPs, Muñoz Caro et al 2006) and solar system organics (Dalle Ore et al 2011). Thus, the most physically-realistic carbonaceous grain materials, albeit inherently rather complex, would appear to be the extensive family of (hydrogenated) amorphous carbons, a-C(:H) 4 .…”

Section: Hydrogenated Amorphous Carbons A-c(:h)mentioning

confidence: 99%

“…Hydrogenated amorphous carbon materials, a-C(:H), are macroscopically-structured, contiguous network, solid-state materials comprised of only carbon and hydrogen atoms. The properties of a-C(:H) materials have been well-studied within both the physics and astrophysics communities (e.g., Phillips 1979;Döhler et al 1980;Thorpe 1983;Robertson 1986Robertson , 1988Robertson , 1991Robertson , 2001Robertson , 2002Robertson & O'Reilly 1987;Angus & Jansen 1988;Angus & Hayman 1988;Tamor & Wu 1990;Mennella et al 1995Mennella et al , 1996Mennella et al , 2003Ferrari & Robertson 2000Kassavetis et al 2007;Llamas-Jansa et al 2007;Mennella 2008;Gadallah et al 2011;Jones 2012a,b,c).…”

Section: Hydrogenated Amorphous Carbons A-c(:h)mentioning

confidence: 99%

“…Indeed, variations in the dust properties from one region to another have long been interpreted as due to dust evolution (e.g., Lefevre 1974;Jura 1980;Aannestad & Greenberg 1983;Whittet et al 1992Whittet et al , 2001Ossenkopf 1993;Stepnik et al 2003). For example, photon, ion and electron irradiation can induce changes in the dust chemical composition and structure (e.g., Demyk et al 2001Demyk et al , 2004, hydrogenation and accretion can drive changes in the grain chemical composition (e.g., Hecht 1986;Sorrell 1990Sorrell , 1991Mennella 2008Mennella , 2010Jones 2012a) and accretion/coagulation will change the grain structure (e.g., Köhler et al 2011Köhler et al , 2012Köhler et al , 2015Jones et al 2014Jones et al , 2016. All of these processes directly affect the dust optical properties (i.e., the particle absorption and scattering cross-sections) as the composition, structure and shape of the grains evolve as they transit from one region to another.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The global dust modelling framework THEMIS

Jones

Koehler

Ysard

et al. 2017

A&A

273

345

View full text Add to dashboard Cite

Here we introduce the interstellar dust modelling framework THEMIS (The Heterogeneous dust Evolution Model for Interstellar Solids), which takes a global view of dust and its evolution in response to the local conditions in interstellar media. This approach is built upon a core model that was developed to explain the dust extinction and emission in the diffuse interstellar medium. The model was then further developed to self-consistently include the effects of dust evolution in the transition to denser regions. The THEMIS approach is under continuous development and we are currently extending the framework to explore the implications of dust evolution in HII regions and the photon-dominated regions associated with star formation. We provide links to the THEMIS, DustEM and DustPedia websites where more information about the model, its input data and applications can be found.

show abstract

Section: Hydrogenated Amorphous Carbons A-c(:h)mentioning

confidence: 99%

Section: Hydrogenated Amorphous Carbons A-c(:h)mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The global dust modelling framework THEMIS

Jones

Koehler

Ysard

et al. 2017

A&A

273

345

View full text Add to dashboard Cite

show abstract

“…We assume a cosmic abundance of ∼ 400 ppm for carbon, 5 the dust model requires 233 ppm 15 therefore leaving ∼ 167 ppm available for accretion onto dust in the form of a-C(:H) mantles. It has been shown that H atom incorporation into carbonaceous materials at low temperature (T kin = 80 K) can lead to their hydrogenation [37][38][39][40] and we therefore consider this possibility within the framework of our qualitative model. The H atom sticking time-scale onto all grains is…”

Section: Hydrocarbon Dust (Re-)accretionmentioning

confidence: 99%

The cycling of carbon into and out of dust

et al. 2014

View full text Add to dashboard Cite

Observational evidence seems to indicate that the depletion of interstellar carbon into dust shows rather wide variations and that carbon undergoes rather rapid recycling in the interstellar medium (ISM). Small hydrocarbon grains are processed in photo-dissociation regions by UV photons and by ion and electron collisions in interstellar shock waves and by cosmic rays. A significant fraction of hydrocarbon dust must therefore be re-formed by accretion in the dense, molecular ISM. A new dust model [Jones et al., A&A, 2013, 558, A62] shows that variations in the dust observables, in the diffuse interstellar medium (n H ≤ 10 3 cm −3 ), can be explained by systematic and environmentally-driven changes in the small hydrocarbon grain population. Here we explore the consequences of gas-phase carbon accretion onto the surfaces of grains in the transition regions between the diffuse ISM and molecular clouds [e.g., Jones, A&A, 2013, 555, A39]. We find that significant carbonaceous dust re-processing and/or mantle accretion can occur in the outer regions of molecular clouds and that this dust will have significantly different optical properties from the dust in the adjacent diffuse ISM. We conclude that the (re-)processing and cycling of carbon into and out of dust is perhaps the key to advancing our understanding of dust evolution in the ISM.

show abstract

“…However, the wavelength peak of this feature and its overall structure differ appreciably from the symmetric and asymmetric aliphatic hydrocarbon bands of the DISM . Mennella (2008aMennella ( , 2010 proposed a scenario in which the different conditions in dense clouds with respect to diffuse regions (e.g. ice coating of the dust grains, H atom temperature) may inhibit the formation of CH 2 and CH 3 groups, while the formation of the 3.47 μm band can proceed (see also Sect.…”

Section: The Nature Of Interstellar Organics and Their Relationship Tmentioning

confidence: 99%

Organic materials in planetary and protoplanetary systems: nature or nurture?

Ore

Fulchignoni

Cruikshank

et al. 2011

A&A

View full text Add to dashboard Cite

Aims. The objective of this work is to summarize the discussion of a workshop aimed at investigating the properties, origins, and evolution of the materials that are responsible for the red coloration of the small objects in the outer parts of the solar system. Because of limitations or inconsistencies in the observations and, until recently, the limited availability of laboratory data, there are still many questions on the subject. Our goal is to approach two of the main questions in a systematic way: -Is coloring an original signature of materials that are presolar in origin ("nature") or stems from post-formational chemical alteration, or weathering ("nurture")? -What is the chemical signature of the material that causes spectra to be sloped towards the red in the visible? We examine evidence available both from the laboratory and from observations sampling different parts of the solar system and circumstellar regions (disks). Methods. We present a compilation of brief summaries gathered during the workshop and describe the evidence towards a primordial vs. evolutionary origin for the material that reddens the small objects in the outer parts of our, as well as in other, planetary systems. We proceed by first summarizing laboratory results followed by observational data collected at various distances from the Sun. Results. While laboratory experiments show clear evidence of irradiation effects, particularly from ion bombardment, the first obstacle often resides in the ability to unequivocally identify the organic material in the observations. The lack of extended spectral data of good quality and resolution is at the base of this problem. Furthermore, that both mechanisms, weathering and presolar, act on the icy materials in a spectroscopically indistinguishable way makes our goal of defining the impact of each mechanism challenging. Conclusions. Through a review of some of the workshop presentations and discussions, encompassing laboratory experiments as well as observational data, we infer that both "nature" and "nurture" are instrumental in the coloration of small objects in the outer parts Article published by EDP Sciences A98, page 1 of 14 A&A 533, A98 (2011) of the solar system. While in the case of some observations it is clear that the organic reddening material originated before the solar nebula (i.e. presolar grains found in meteorites), for many other cases pointers are not as clear and indicate a concurrence of both processes.

show abstract

Activation of the 3.47 μm Band by H Atom Irradiation of Carbon Grains Covered with a Water Ice Layer at 12 K

Cited by 23 publications

References 27 publications

The global dust modelling framework THEMIS

The global dust modelling framework THEMIS

The cycling of carbon into and out of dust

Organic materials in planetary and protoplanetary systems: nature or nurture?

Contact Info

Product

Resources

About