We present an investigation into the morphological features of the Milky Way. We use smoothed particle hydrodynamics (SPH) to simulate the interstellar medium (ISM) in the Milky Way under the effect of a number of different gravitational potentials representing spiral arms and bars, assuming the Milky Way is grand design in nature. The gas is subject to ISM cooling and chemistry, enabling us to track the evolution of molecular gas. We use a 3D radiative transfer code to simulate the emission from the SPH output, allowing for the construction of synthetic longitude-velocity (l-v) emission maps as viewed from the Earth. By comparing these maps with the observed emission in CO from the Milky Way, we infer the arm/bar geometry that provides a best fit to our Galaxy. We find that it is possible to reproduce nearly all features of the l-v diagram in CO emission. There is no model, however, that satisfactorily reproduces all of the features simultaneously. Models with 2 arms cannot reproduce all the observed arm features, while 4 armed models produce too bright local emission in the inner Galaxy. Our best fitting models favour a bar pattern speed within 50-60km/s/kpc and an arm pattern speed of approximately 20km/s/kpc, with a bar orientation of approximately 45 degrees and arm pitch angle between 10-15 degrees.
Optimized HDBSCAN clustering for reconstructing the merger history of the Milky Way: applications and limitations
Astrophysics Research Institute, Liverpool John Moores University(利物浦约翰摩尔斯大学天体物理研究所);School of Computer Science and Mathematics, Liverpool John Moores University(利物浦约翰摩尔斯大学计算机科学与数学学院)
Dynamics and Morphology of the Milky Way Spiral Arms from the Metallicity Distribution and Radial Mixing
尽管径向迁移在盘星系中是一个普遍存在的过程,但它在恒星盘演化中的意义并不总是通过全球趋势反映出来。然而,还有其他关键的观测数据,如金属丰度分布函数(metallicity distribution function,简写为EAF),可能会在这个问题上有所启发。我们认为,螺旋线的形状不仅告诉我们恒星盘是否经历了径向迁移,而且它还包含了触发它的结构的重要线索。具体来说,螺旋线包含有关螺旋图案的动力学和形态的信息。为了限制螺旋参数,我们在模拟中加入了详细的化学标记;这使我们能够限制银河系螺旋臂的结构参数,以及限制化学演化模型朝向银河系圆盘中心的方法,在那里没有化学模型提供信息。我们还发现,太阳不太可能在其当前的银河系中心位置附近形成,因此将太阳视为太阳附近化学丰度的代表可能是不准确的。我们还表明,银河系的恒星盘,经过动态和化学演变为5 Gyr,保留80%的原始全球金属丰度梯度,尽管遭受了重要的加热和径向迁移,这意味着在一个给定的星系中存在的金属丰度梯度,并不能保证径向混合没有发挥作用,在其演变。
The morphology and kinematics of the gaseous circumgalactic medium of Milky Way mass galaxies -- II. comparison of IllustrisTNG and Illustris simulation results
J-PLUS Reconstructing the Milky Way Disc's star formation history with twelve-filter photometry
Centro de Estudios de Física del Cosmos de Aragón (CEFCA)(阿拉贡宇宙物理研究中心);Instituto de Astrofísica de Andalucía – Consejo Superior de Investigaciones Científicas (IAA-CSIC)(安达卢西亚天体物理学研究所 - 西班牙国家研究委员会);Unidad Asociada CEFCA-IAA, CEFCA, Unidad Asociada al CSIC por el IAA y el IFCA(CEFCA-IAA联合单位,CEFCA,由IAA和IFCA与CSIC关联的单位);Centro de Astrobiología (CAB), CSIC-INTA(天体生物学中心,西班牙国家研究委员会-国家航空航天技术研究所);NSF NOIRLab(美国国家科学基金会NOIR天文台实验室);Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo(圣保罗大学天文、地球物理与大气科学学院);Department of Astronomy, Beijing Normal University(北京师范大学天文系);Universidade Federal do Rio de Janeiro, Observatório do Valongo(里约热内卢联邦大学瓦隆戈天文台);Instituto de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México(墨西哥国立自治大学射电天文学与天体物理学研究所)
Morphological Statistic of Milky Way-like Galaxies
Purple Mountain Observatory, Chinese Academy of Sciences(中国科学院紫金山天文台);School of Astronomy and Space Science, University of Science and Technology of China(中国科学技术大学天文与空间科学学院);Three Gorges University(三峡大学);National Astronomical Observatories, Chinese Academy of Sciences(中国科学院国家天文台);School of Astronomy and Space Science, University of Chinese Academy of Sciences(中国科学院大学天文与空间科学学院)
Reconstructing the orbits of Milky Way dwarf galaxies: A Large Magellanic Cloud perspective
Instituto de Astrofísica de Andalucía, CSIC(安达卢西亚天体物理研究所,西班牙高等科学理事会);Space Telescope Science Institute(太空望远镜科学研究所);Center for Astrophysical Sciences, The William H. Miller III Department of Physics & Astronomy, Johns Hopkins University(约翰斯·霍普金斯大学天体物理学中心威廉·H·米勒三世物理与天文系);Instituto de Astrofísica de Canarias(加那利天体物理研究所);Departamento de Astrofísica, Universidad de La Laguna(拉帕鲁纳大学天体物理系);Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences(波兰科学院尼古拉·哥白尼天文学中心);Institute for Astronomy, University of Edinburgh(爱丁堡大学天体物理研究所);David A. Dunlap Department of Astronomy & Astrophysics, University of Toronto(多伦多大学大卫·A·邓普克天文与天体物理系);AURA for the European Space Agency (ESA), Space Telescope Science Institute(欧洲空间局(ESA)AURA机构太空望远镜科学研究所);Department of Astronomy, Univer(天文学系)
The AGORA High-resolution Galaxy Simulations Comparison Project. IX - Part 2: Effects of a Major Galaxy Merger on the Stellar Morphology of a Milky Way-mass Galaxy Progenitor
Center for AstroPhysical Surveys, National Center for Supercomputing Applications(国家超级计算应用中心天文物理调查中心);Center for Theoretical Physics, Department of Physics and Astronomy, Seoul National University(首尔国立大学物理与天文学系理论物理中心);Departamento de Física de la Tierra y Astrofísica, Fac. de C.C. Físicas, Universidad Complutense de Madrid(马德里康普顿斯大学理学院地球与天体物理学系);Instituto de Física de Partículas y del Cosmos, IPARCOS, Fac. C.C. Físicas, Universidad Complutense de Madrid(马德里康普顿斯大学理学院粒子与宇宙物理研究所);Lund Observatory, Division of Astrophysics, Department of Physics, Lund University(隆德大学物理系天体物理学部隆德天文台)
Reconstructing Galactic Gravitational Potentials from Stellar Kinematics with Physics-Informed Neural Networks
Department of Physics and Kavli Institute for Astrophysics and Space Research, MIT(麻省理工学院物理系与卡弗里天体物理学和空间研究研究所);The NSF AI Institute for Artificial Intelligence and Fundamental Interactions, Massachusetts Institute of Technology(美国国家科学基金会人工智能基础交互作用研究所,麻省理工学院)
Bulgeless Evolution And the Rise of Discs (BEARD) III. A numerical simulation view of satellites around Milky-Way analogues
Universidad de La Laguna(拉各拉大学);Instituto de Astrofísica de Canarias(加那利天体物理研究所);Donostia International Physics Centre (DIPC)(多诺斯蒂亚国际物理中心);Universidad de Córdoba(科尔多瓦大学)
Using synthetic emission maps to constrain the structure of the Milky Way
介绍了银河系结构研究的现状。我们使用光滑粒子流体动力学(SPH)模拟ISM气体在银河系中的影响下的一些不同的引力势代表的旋臂和核酒吧,固定和随时间变化。气体经过ISM冷却和化学处理,使我们能够跟踪CO和HI密度。我们使用一个三维网格为基础的辐射转移代码来模拟从SPH输出的排放,允许从地球上看合成的光速地图的建设。通过将这些图与银河系中观测到的CO和HI发射进行比较(Dame et al. 2001,Kalberla et al. 2005),我们可以推断出最适合我们银河系的臂/棒几何形状。通过这样做,我们的目标是回答有关银河系形态的关键问题,如旋臂的数量,条和臂的模式速度,臂的俯仰角和条的形状
Bar-Informed Kinematic-Distance Mapping of Molecular Gas in the Inner Milky Way
Amanogawa Galaxy Astronomy Research Center, Graduate School of Science and Engineering, Kagoshima University(鹿儿大学理工学研究科银河天体物理研究中心);Division of Science, National Astronomical Observatory of Japan(日本国立天文台理学院)