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相关论文: A Giant Disk Galaxy Two Billion Years After The Bi…

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Giant bulgeless disk galaxies, theoretically expected to be rare in the early Universe, have been confirmed by the James Webb Space Telescope (JWST) to exist as early as 2 billion years after the Big Bang. These morphologically extreme…

Massive disk galaxies like the Milky Way are expected to form at late times in traditional models of galaxy formation, but recent numerical simulations suggest that such galaxies could form as early as a billion years after the Big Bang…

星系天体物理 · 物理学 2020-05-21 Marcel Neeleman , J. Xavier Prochaska , Nissim Kanekar , Marc Rafelski

At redshift z = 2, when the Universe was just three billion years old, half of the most massive galaxies were extremely compact and had already exhausted their fuel for star formation(1-4). It is believed that they were formed in intense…

In the local (redshift z~0) Universe, collisional ring galaxies make up only ~0.01% of galaxies and are formed by head-on galactic collisions that trigger radially propagating density waves. These striking systems provide key snapshots for…

Present-day disc galaxies often exhibit distinct thin and thick discs. The formation mechanisms of the two discs and the timing of their onset remain open questions. To address these questions, we select edge-on galaxies from flagship JWST…

星系天体物理 · 物理学 2025-04-11 Takafumi Tsukui , Emily Wisnioski , Joss Bland-Hawthorn , Ken Freeman

Whether among the myriad tiny proto-galaxies there exists a population with similarities to present day galaxies is an open question. We show, using BlueTides, the first hydrodynamic simulation large enough to resolve the relevant scales,…

星系天体物理 · 物理学 2015-08-06 Yu Feng , Tiziana Di Matteo , Rupert Croft , Ananth Tenneti , Simeon Bird , Nicholas Battaglia , Stephen Wilkins

Recent observations with the James Webb Space Telescope (JWST) have begun to reveal a surprising morphological diversity in galaxies within the first billion years after the Big Bang, including indications of structural maturity previously…

星系天体物理 · 物理学 2025-10-30 Anshuman Borgohain , Kanak Saha

While rotation-supported gas disks are known to exist as early as at z ~ 7, it is still a general belief that stellar disks form late in the Universe. This picture is now being challenged by the observations from the James Webb Space…

星系天体物理 · 物理学 2024-10-22 Haojing Yan , Bangzheng Sun , Chenxiaoji Ling

Cosmological models predict that galaxies forming in the early Universe experience a chaotic phase of gas accretion and star formation, followed by gas ejection due to feedback processes. Galaxy bulges may assemble later via mergers or…

According to the current understanding of cosmic structure formation, the precursors of the most massive structures in the Universe began to form shortly after the Big Bang, in regions corresponding to the largest fluctuations in the cosmic…

Rest-frame optical observations with the James Webb Space Telescope (JWST) have uncovered a population of massive galaxies, exceeding $10^{10}$ solar masses, present less than a billion years after the Big Bang. The large stellar masses of…

The formation and evolution of galactic disks is particularly important for understanding how galaxies form and evolve, and the cause of the variety in which they appear to us. Ongoing large surveys, made possible by new instrumentation at…

星系天体物理 · 物理学 2015-05-27 P. C. van der Kruit , K. C. Freeman

Submillimeter bright galaxies in the early Universe are vigorously forming stars at ~1000 times higher rate than the Milky Way. A large fraction of stars is formed in the central 1 kiloparsec region, that is comparable in size to massive,…

Most massive galaxies are thought to have formed their dense stellar cores at early cosmic epochs. However, cores in their formation phase have not yet been observed. Previous studies have found galaxies with high gas velocity dispersions…

[Abridged] Over the past two decades observations and theoretical simulations have established a global frame-work of galaxy formation and evolution in the young Universe. Galaxies formed as baryonic gas cooled at the centres of collapsing…

Using the deepest and the most complete set of observations of distant galaxies, we investigate how extended disks could have formed. Observations include spatially-resolved kinematics, detailed morphologies and photometry from UV to…

宇宙学与河外天体物理 · 物理学 2015-05-30 F. Hammer , M. Puech , H. Flores , E. Athanassoula , Y. B. Yang , J. L. Wang , M. Rodrigues , S. Fouquet

I briefly review the growing evidence that thick stellar disks surround most edge-on disk galaxies. Recent studies show that these extragalactic thick disks have old ages, low metallicities, long scale lengths, and moderately flattened…

天体物理学 · 物理学 2007-05-23 Julianne J. Dalcanton , Anil Seth , Peter Yoachim

In local disk galaxies such as our Milky Way, older stars generally inhabit a thicker disk than their younger counterparts. Two competing models have attempted to explain this result: one in which stars first form in thin disks that…

The morphologies of disk galaxies begin to deviate systematically from those of nearby galaxies at surprisingly low redshifts, possibly as low as z=0.3. This corresponds to a time ~3.5 Gyr in the past, which is only one quarter of the…

天体物理学 · 物理学 2007-05-23 Roberto G. Abraham , Sidney van den Bergh

Early galaxy formation, initiated by the dark matter and gas assembly, evolves through frequent mergers and feedback processes into dynamically hot, chaotic structures. In contrast, dynamically cold, smooth rotating disks have been observed…

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