Unusual infrared emission toward Sgr B2: possible planar C24
Unusual infrared emission toward Sgr B2: possible planar C24
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朝向 Sgr B2 的异常红外发射：可能是平面 C24
DOI：
10.1088/1674-4527/19/10/141
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发表时间：
2019-05
影响因子：
1.8
通讯作者：
Li Aigen
中科院分区：
文献类型：
--
作者：
Chen Xiu-Hui;Xiang Fu-Yuan;Yang Xue-Juan;Li Aigen
由于多环芳烃(PAH)分子的光化学处理和/或石墨颗粒的碰撞破碎，星际介质(ISM)中可能存在星际石墨烯。事实上，通过将观测到的扩散ISM的紫外线(UV)消光和红外(IR)发射与石墨烯的预测结果进行比较，在不违反观测限制的情况下，高达2%的星际碳被锁定在石墨烯中。虽然在几个银河系和河外行星星云中可能检测到了平面C24，这是一小块石墨烯，但在星际环境中还没有检测到石墨烯。在这项工作中，我们搜索了C24在∼6.6，9.8和20μm处朝着高质量恒星形成区SGR B2的特征红外特征，并找到了朝着R.A.(J2000)=267.05855°和Decl方向的候选目标。(J2000)=−28.01479°，其斯皮策/红外光谱在∼6.637，9.853和20.050μm处出现三个峰，这三个峰似乎与C24的峰一致。在该地区也可以看到C60的可能特征。候选区是由大质量恒星或星团加热的温暖尘埃环境，与WISE黑子(恒星形成活动的示踪)有关，靠近HII区候选IRAS 17450-2759年，并被∼5‘内的7个年轻候选星体包围，这表明C24的产生和/或激发可能与恒星形成活动有关。
Interstellar graphene could be present in the interstellar medium (ISM), resulting from the photochemical processing of polycyclic aromatic hydrocarbon (PAH) molecules and/or collisional fragmentation of graphitic particles. Indeed, by comparing the observed ultraviolet (UV) extinction and infrared (IR) emission of the diffuse ISM with that predicted for graphene, as much as ∼2% of total interstellar carbon could be locked up in graphene without violating the observational constraints. While the possible detection of planar C24, a small piece of a graphene sheet, has been reported towards several Galactic and extragalactic planetary nebulae, graphene has not yet been detected in interstellar environments. In this work, we search for the characteristic IR features of C24 at ∼6.6, 9.8 and 20 μm toward Sgr B2, a high-mass star formation region, and find a candidate target toward R.A. (J2000) = 267.05855° and Decl. (J2000) = −28.01479° in Sgr B2 whose Spitzer/IRS spectra exhibit three bands peaking at ∼6.637, 9.853 and 20.050 μm which appear to be coincident with those of C24. Possible features of C60 are also seen in this region. The candidate region is a warm dust environment heated by massive stars or star clusters, associated with a WISE spot (a tracer of star formation activity), close to the HII region candidate IRAS 17450–2759, and is surrounded by seven young stellar object candidates within ∼5′, suggesting that the creation and/or excitation of C24 could be related to star formation activities.
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根据 IRAS 来源改进了 H II 区域的选择标准
影响因子：
4.8
作者：
Yan Qing-Zeng;Xu Ye;Walsh A. J.;Macquart J. P.;MacLeod G. C.;Zhang Bo;Hancock P. J.;Chen Xi;Tang Zheng-Hong
通讯作者：
Tang Zheng-Hong
DOI：
10.1088/0004-6256/136/6/2413
发表时间：
2008-09
期刊：
The Astronomical Journal
影响因子：
--
作者：
T. Robitaille;M. Meade;B. Babler;B. Whitney;K. Johnston;R. Indebetouw;M. Cohen;M. Povich;M. Sewiło;R. Benjamin;E. Churchwell
通讯作者：
T. Robitaille;M. Meade;B. Babler;B. Whitney;K. Johnston;R. Indebetouw;M. Cohen;M. Povich;M. Sewiło;R. Benjamin;E. Churchwell
DOI：
10.1088/0004-637x/739/1/37
发表时间：
2011-07
期刊：
The Astrophysical Journal
影响因子：
--
作者：
D. Aníbal García-Hernández;N. Kameswara Rao;D. Lambert
通讯作者：
D. Aníbal García-Hernández;N. Kameswara Rao;D. Lambert
DOI：
--
发表时间：
2010
期刊：
--
影响因子：
--
作者：
A. Poglitsch;C. Waelkens;N. Geis;H. Feuchtgruber;B. Vandenbussche;L. Rodriguez;O. Krause;E. Renotte-E
通讯作者：
A. Poglitsch;C. Waelkens;N. Geis;H. Feuchtgruber;B. Vandenbussche;L. Rodriguez;O. Krause;E. Renotte-E
影响因子：
6.5
作者：
M. Rosenberg;O. Bern'e;C. Boersma
通讯作者：
M. Rosenberg;O. Bern'e;C. Boersma