PAHs and the Universe最新文献_第3页

Observations of Hydrocarbon Emission in Disks Around Young Stars 年轻恒星周围圆盘中碳氢化合物发射的观测

PAHs and the Universe Pub Date : 2011-03-01 DOI: 10.1051/EAS/1146028

B. Acke

引用次数: 0

The Role of PAHs in the Physics of the Interstellar Medium 多环芳烃在星际介质物理学中的作用

PAHs and the Universe Pub Date : 2011-03-01 DOI: 10.1051/EAS/1146043

L. Verstraete

引用次数: 6

Electronic Spectroscopy of PAHs 多环芳烃的电子光谱

PAHs and the Universe Pub Date : 2011-03-01 DOI: 10.1051/EAS/1146037

T. Pino, Y. Carpentier, G. Féraud, H. Friha, D. Kokkin, T. Troy, N. Chalyavi, P. Bréchignac, T. Schmidt

引用次数: 4

Formation and Evolution of Circumstellar and Interstellar PAHs: A Laboratory Study 星周和星际多环芳烃的形成和演化:实验室研究

PAHs and the Universe Pub Date : 2011-03-01 DOI: 10.1051/EAS/1146021

C. Contreras, C. L. Ricketts, Farid Salama

引用次数: 2

The PAH-DIB Hypothesis PAH-DIB假说

PAHs and the Universe Pub Date : 2011-03-01 DOI: 10.1051/EAS/1146036

N. Cox

引用次数: 5

AKARI Near-Infrared Spectroscopy of 3 Micron PAH and 4 Micron PAD Features 3微米多环芳烃和4微米PAD特征的AKARI近红外光谱分析

PAHs and the Universe Pub Date : 2011-03-01 DOI: 10.1051/EAS/1146006

T. Onaka, I. Sakon, R. Ohsawa, T. Shimonishi, Y. Okada, Masahiro Tanaka, H. Kaneda

{"title":"AKARI Near-Infrared Spectroscopy of 3 Micron PAH and 4 Micron PAD Features","authors":"T. Onaka, I. Sakon, R. Ohsawa, T. Shimonishi, Y. Okada, Masahiro Tanaka, H. Kaneda","doi":"10.1051/EAS/1146006","DOIUrl":"https://doi.org/10.1051/EAS/1146006","url":null,"abstract":"Near-infrared (NIR; 2.5–5 μ m) low-resolution ( λ /Δ λ ~ 100) spectra were obtained for a number of Galactic and extragalactic objects with the Infrared Camera (IRC) in the AKARI warm mission. These data provide us with the first opportunity to make a systematic study of the 3.3–3.5 μ m PAH features in a galactic scale as well as within an object. Whereas the 3.3 μ m band is well resolved in most spectra, the 3.5 μ m band is not clearly separated from the 3.4 μ m band in the IRC spectrum. The intensity ratio of the summation of the 3.4 and 3.5 μ m bands to the 3.3 μ m band shows a tendency to increase towards the Galactic center, although a large variation in the ratio is also seen in a local scale. A search for deuterated PAH features in the 4 μ m region is carried out in IRC NIR spectra. Emission lines originating from the ionized gas together with the detector anomaly hamper an accurate search at certain wavelengths, but little convincing evidence has so far been obtained for the presence of significant features in 4.2–4.7 μ m. A conservative upper limit of a few percents is obtained for the integrated intensity ratio of the 4.4–4.7 μ m possible features to the 3.3–3.5 μ m PAH features in the spectra so far obtained.","PeriodicalId":197011,"journal":{"name":"PAHs and the Universe","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115653296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Near-Infrared Spectroscopy of Interstellar Dust 星际尘埃的近红外光谱

PAHs and the Universe Pub Date : 2011-03-01 DOI: 10.1051/EAS/1146041

F. Boulanger, T. Onaka, P. Pilleri, C. Joblin

{"title":"Near-Infrared Spectroscopy of Interstellar Dust","authors":"F. Boulanger, T. Onaka, P. Pilleri, C. Joblin","doi":"10.1051/EAS/1146041","DOIUrl":"https://doi.org/10.1051/EAS/1146041","url":null,"abstract":"Near infrared observations of reflection nebulae have set the historical ground for the discovery of interstellar PAHs, but since, space observations have focused on their mid-IR features, and data shortward of 5 μ m have remained scarce. The Spitzer/IRAC images in the 3.6 and 4.5 μ m channels do show that the near-IR emission from small dust particles is ubiquitous across the Galaxy, but provide no spectroscopic information. To investigate the nature of this near-IR dust emission, we have obtained AKARI spectroscopic observations, over the 2.5−5 μ m spectral range, for a set of archetype PDRs mapped with the Spitzer spectrometer at mid-IR wavelengths. These AKARI data supplement earlier observations with the SWS ISO spectrometer, in providing the gain in sensitivity needed to observe low excitation sources, and the spatial information required to spatially correlate near-IR spectroscopic signatures with physical conditions and observed changes in mid-IR spectra. This paper presents the first results of the data analysis, in relation to two open questions on interstellar PAHs. (1) Is there an evolutionary link from aliphatic carbon dust to PAHs? (2) What is the origin of the near-IR dust continuum? The AKARI spectra display features longward of the main 3.29 μ m PAH feature, and continuum emission. The intensity ratio between the features ascribed to aliphatic CH bonds and the 3.29 μ m aromatic band, varies spatially in a way that may be interpreted as evidence for aromatization of the smallest dust particles by photo-processing. The continuum displays a striking step-increase across the 3.29 μ m feature. We also present a spectrum of a photodissociation region with a feature at 4.65 μ m, which has been speculated to be related to the CD stretch in aliphatic hydrocarbon side-groups on PAHs.","PeriodicalId":197011,"journal":{"name":"PAHs and the Universe","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133256861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Solid State Molecular Reactors in Space 太空中的固态分子反应器

PAHs and the Universe Pub Date : 2011-03-01 DOI: 10.1051/EAS/1146033

M. Maurette

{"title":"Solid State Molecular Reactors in Space","authors":"M. Maurette","doi":"10.1051/EAS/1146033","DOIUrl":"https://doi.org/10.1051/EAS/1146033","url":null,"abstract":"Lunar minerals and impact glasses, convert the polyatomic beam of solar wind (SW) ions\u0000 into a flux of small molecules ( e.g. , H 2 , N 2 ,\u0000 H 2 O, CO, CO 2 , CH 4 , C 2 H 4 ,\u0000 C 2 H 6 , HCN, metal carbides and deuterides, etc.). They thus behave\u0000 as “Solid State Molecular Reactors”. Moreover, ~100–200 μ m\u0000 size micrometeoroids ( μ Ms) have also been exposed to the SW in the\u0000 zodiacal cloud, before being captured by the Earth and recovered as Antarctic\u0000 micrometeorites. They are mostly composed of a PAH-rich hydrous-carbonaceous material,\u0000 which amplifies their power as molecular reactors. In particular, during the first\u0000 ~200 Myr of the post-lunar period, about 75% of the μ Ms have\u0000 been melted and/or volatilized upon atmospheric entry. The release of their volatile\u0000 species triggered a cosmic volcanism around the mesopause that ruled the formation of the\u0000 early Earth’s atmosphere and climate. Furthermore, a fraction of the μ Ms\u0000 that survive unmelted upon atmospheric entry did settle on the proto-oceans floors. Upon\u0000 further burial in sediments their constituent PAH-rich kerogen was cracked into abiotic\u0000 oil, which generated giant oil slicks that fed prebiotic chemistry. Many stars, of all\u0000 ages and types, are embedded into a secondary debris-disk loaded with ion implanted\u0000 μ Ms. Some of them are expelled to the interstellar medium (ISM) where\u0000 they behave first as “dormant-invisible” molecular reactors, until they became reactivated\u0000 by various processes to synthesize interstellar molecules. This short paper only focus on\u0000 some highlights of this research dealing with the synthesis of important interstellar\u0000 molecules, including the most abundant ones (H 2 and CO) and H 2 O, HCN\u0000 and PAHs, all involved in prebiotic chemistry.","PeriodicalId":197011,"journal":{"name":"PAHs and the Universe","volume":"20 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132758472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

[FePAH]+ Complexes and [FexPAHy]+ Clusters in the Interstellar Medium: Stability and Spectroscopy 星际介质中的[FePAH]+配合物和[FexPAHy]+星团:稳定性和光谱学

PAHs and the Universe Pub Date : 2011-03-01 DOI: 10.1051/EAS/1146045

A. Simon, M. Rapacioli, F. Spiegelman, C. Joblin

引用次数: 1

Astronomical Observations of the PAH Emission Bands 多环芳烃发射带的天文观测

PAHs and the Universe Pub Date : 2011-03-01 DOI: 10.1051/EAS/1146002

E. Peeters

引用次数: 5