G+0.693-0.03 is a quiescent molecular cloud located within the Sagittarius B2 (Sgr B2) star-forming complex. Recent spectral surveys have shown that it represents one of the most prolific repositories of complex organic species in the Galaxy. The origin of such chemical complexity, along with the small-scale physical structure and properties of G+0.693-0.03, remains a mystery. In this paper, we report the study of multiple molecules with interferometric observations in combination with single-dish data in G+0.693-0.03. Despite the lack of detection of continuum source, we find small-scale (0.2 pc) structures within this cloud. The analysis of the molecular emission of typical shock tracers such as SiO, HNCO, and CH$_3$OH unveiled two molecular components, peaking at velocities of 57 and 75 km s$^{-1}$. They are found to be interconnected in both space and velocity. The position-velocity diagrams show features that match with the observational signatures of a cloud-cloud collision. Additionally, we detect three series of class \rom{1} methanol masers known to appear in shocked gas, supporting the cloud-cloud collision scenario. From the maser emission we provide constraints on the gas kinetic temperatures ($\sim$30-150 K) and H$_2$ densities (10$^4$-10$^5$ cm$^{-2}$). These properties are similar to those found for the starburst galaxy NGC253 also using class \rom{1} methanol masers, suggested to be associated with a cloud-cloud collision. We conclude that shocks driven by the possible cloud-cloud collision is likely the most important mechanism responsible for the high level of chemical complexity observed in G+0.693-0.03.
The CaFe Project: Optical FeII and Near-Infrared Ca II triplet emission in active galaxies. II. The driver(s) of the Ca II and Fe II and its potential use as a chemical clock
The Galactic centre G+0.633-0.0604 molecular cloud: A new astrochemical gold mine: II. Chemical richness
Centro de Astrobiología (CAB), CSIC-INTA(天体生物学中心);Universidad Complutense de Madrid(马德里康普顿斯大学);Max-Planck-Institut für extraterrestrische Physik(马克斯·普朗克地外物理研究所);European Southern Observatory(欧洲南方天文台);Joint ALMA Observatory(ALMA联合天文台);RIKEN(理化学研究所)
The ionization structure and chemical history in isolated H ii regions of dwarf galaxies with VIMOS/IFU II. The Leo A galaxy
Universidad Andres Bello(安德烈斯贝略大学);European Southern Observatory(欧洲南方天文台);INAF – Osservatorio Astronomico di Trieste(意大利国家天体物理研究所的里雅斯特天文台);INAF - Osservatorio Astronomico di Padova(意大利国家天体物理研究所帕多瓦天文台)
Bulk vs. turbulent motions at the centres of galaxy clusters: AGN-driven turbulence according to TNG-Cluster
Max-Planck-Institut für Astronomie(马克斯·普朗克天文学研究所);Fakultät für Physik und Astronomie, Universität Heidelberg(海德堡大学物理与天文学院);Département de Physique, Université de Montréal(蒙特利尔大学物理系);Universität Heidelberg, Zentrum für Astronomie, ITA(海德堡大学天文学中心);Universität Heidelberg, Interdisziplinäres Zentrum für Wissenschaftliches Rechnen(海德堡大学跨学科科学计算中心)
Large-scale and local environmental drivers of quenching: tracing H$α$ concentration in X-ray and optical galaxy groups
The University of Sydney(悉尼大学);ARC Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D)(三维全天空天体物理学卓越研究中心);Research School of Astronomy and Astrophysics, Australian National University(澳大利亚国立大学天文与天体物理研究学院);Beijing Normal University(北京师范大学);Max Planck Institute for Extraterrestrial Physics(马克斯·普朗克地外物理研究所)
The complex organic molecular content in the L1517B starless core
Centro de Astrobiología (CAB), CSIC-INTA(天体生物学中心(CAB),西班牙国家研究委员会-国家航空航天技术研究所);Ural Federal University(乌拉尔联邦大学);Max Planck Institute for Extraterrestrial Physics(马克斯·普朗克地外物理学研究所);Leiden Observatory, Leiden University(莱顿天文台,莱顿大学);Department of Physics and Astronomy, University College London(伦敦大学学院物理与天文系);Chalmers University of Technology(查尔姆斯理工大学)
Probing the chemical complexity of amines in the ISM: detection of vinylamine (C$_2$H$_3$NH$_2$) and tentative detection of ethylamine (C$_2$H$_5$NH$_2$)
胺,特别是伯胺(R-NH $_2$)与氨基酸的原始合成密切相关,因为它们共享相同的结构骨架。然而,在ISM中只确定了有限数量的胺,这阻止了我们研究它们的化学以及它们与可能导致生命出现的前生物物种的关系。在这封信中,我们报告了在银河系中心云G+0.693-0.027中首次星际探测到乙烯胺(C $_2$ H $_3$ NH $_2$)和乙胺(C $_2$ H $_5$ NH $_2$)。推导出的H $_2$丰度分别为(3.3 $\pm$ 0.4)$\times$ 10 $^{-10}$和(1.9 $\pm$ 0.5)$\times$ 10 $^{-10}$。C $_2$ H $_3$ NH $_2$和C $_2$ H $_5$ NH $_2$相对于甲胺(CH $_3$ NH $_2$)的推断丰度比分别为$\sim$ 0.02和$\sim$ 0.008。推导出的C $_2$ H $_3$ NH $_2$、C $_2$ H $_5$ NH $_2$和其他几个NH $_2$轴承物种的丰度进行了比较,对高质量和低质量的恒星形成区。根据最近的化学和实验室研究,可能的化学路线星际合成的C $_2$ H $_3$ NH $_2$和C $_2$ H $_5$ NH $_2$进行了讨论。
The Galactic Centre G+0.633-0.0604 Molecular Cloud: A New Gold Mine for Astrochemistry
Centro de Astrobiología (CAB), CSIC-INTA(天体生物学中心(CAB),西班牙国家航空航天技术研究所/西班牙国家科学研究委员会);Center for Astrochemical Studies, Max-Planck-Institut für extraterrestrische Physik(系外行星物理研究所天体化学研究)
Chemical enrichment in the Ophiuchus cluster core studied by high-resolution XRISM spectroscopy
Institute of Space and Astronautical Science, JAXA(宇宙科学研究所);Department of Physics, Tokyo Metropolitan University(东京都立大学物理系);Department of Astrophysics and Atmospheric Sciences, Kyoto Sangyo University(京都产业大学天体物理学与大气科学系);Department of Physics, Hiroshima University(广岛大学物理系);Department of Physics, Saitama University(埼玉大学物理系)
利用高分辨率XRISM光谱学研究Ophiuchus团核心的化学富集,发现其X/Fe比值与太阳一致,通过核心坍缩和Ia型超新星模型解释丰度模式,揭示Ca的不足可能由Ca-rich gap transients贡献。
INAF, Osservatorio Astronomico di Trieste(意大利国家天体物理研究所的里雅斯特天文台);Department of Astronomy, University of Florida(佛罗里达大学天文学系);IFPU, Institute for Fundamental Physics of the Universe(宇宙基础物理研究所);IATE - Instituto de Astronomía Teórica y Experimental, Consejo Nacional de Investigaciones Científicas y Técnicas de la República Argentina (CONICET), Universidad Nacional de Córdoba(阿根廷国家科学技术研究委员会理论及实验天体物理研究所,科尔多瓦国立大学);Cosmic Dawn Center at the Niels Bohr Institute, University of Copenhagen and DTU-Space, Technical University of Denmark(哥本哈根大学尼尔斯·玻尔学院宇宙黎明中心,丹麦技术大学空间部);INAF - Osservatorio Astronomico di Roma(意大利国家天体物理研究所罗马天文台);University of Ljubljana FMF(卢布尔雅那大学数学与物理学院);INAF–Osservatorio Astrofisico di Arcetri(意大利国家天体物理研究所阿切尔蒂天文台)