A Spatially Resolved Map of the Kinematics, Star-Formation and Stellar Mass Assembly in a Star-Forming Galaxy at z=4.9
Mark Swinbank, Tracy Webb, Johan Richard, Richard Bower, Richard Ellis, Garth Illingworth, Tucker Jones, Mariska Kriek, Ian Smail, Dan Stark, Pieter Van Dokkum
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Accepted for publication in MNRAS. 11 pages, 7 figures
We present a detailed study of the spatially resolved kinematics, star-formation and stellar mass in a highly amplified galaxy at z=4.92 behind the lensing cluster MS1358+62. We use the observed optical, near- and mid-infrared imaging from HST ACS & NICMOS and Spitzer IRAC to derive the stellar mass and the Gemini/NIFS IFU to investigate the velocity structure of the galaxy from the nebular [OII] emission. Using a detailed gravitational lens model, we account for lensing amplification factor 12.+/-2.0 and find that this intrinsically L* galaxy has a stellar mass of M*=7+/-2x10^8Mo, a dynamical mass of Mdyn=3+/-1x10^9csc^2(i)Mo (within of 2kpc) and a star-formation rate of 42+/-8Mo/yr. The source-plane UV/optical morphology of this galaxy is dominated by five discrete star-forming regions. Exploiting the dynamical information we derive masses for individual star-forming regions of Mcl~10^(8-9)Mo with sizes of ~200pc. We find that, at a fixed size, the star-formation rate density within these HII regions is approximately two orders of magnitude greater than those observed in local spiral/starburst galaxies, but consistent with the most massive HII regions in the local Universe such as 30Dor. Finally, we compare the spatially resolved nebular emission line velocity with the Ly-alpha and UV-ISM lines and find that this galaxy is surrounded by a galactic scale outflow in which the Ly-alpha appears redshifted by ~150km/s and the UV-ISM lines blue-shifted by -200km/s from the (systemic) nebular emission. The velocity structure of the outflow mirrors that of the nebular emission suggesting the outflow is young (~15Myr), and has yet to burst out of the system. Taken together, these results suggest that this young galaxy is undergoing its first major epoch of mass assembly.
Using dark matter haloes identified in a large $N$-body simulation, we study halo assembly bias, with halo formation time, peak maximum circular velocity, concentration, and spin as the assembly variables. Instead of grouping haloes at fixed mass into different percentiles of each assembly variable, we present the joint dependence of halo bias on the {\it values} of halo mass and each assembly variable. In the plane of halo mass and one assembly variable, the joint dependence can be largely described as halo bias increasing outward from a global minimum. We find it unlikely to have a combinati…
The kinematics of galaxies provide valuable insights in their physics and assembly history. Kinematics are governed not only by the gravitational potential, but also by merger events and stellar feedback processes such as stellar winds and supernova explosions. Aims. We aim at identifying what governs the kinematics in a sample of SDSS selected nearby starburst galaxies, by obtaining spatially resolved measurements of the gas and stellar kinematics. We obtain near-infrared integral field K-band spectroscopy with VLT/SINFONI of 15 compact starburst galaxies. We derive the integrated as well as …
TDCOSMO XXIV. First spatially resolved kinematics of the lens galaxy obtained using JWST-NIRSpec to improve time-delay cosmography
Kavli Institute for Cosmological Physics, University of Chicago(芝加哥大学卡弗里宇宙物理学研究所);Center for Astronomy, Space Science and Astrophysics, Independent University, Bangladesh(孟加拉独立大学天文学、空间科学与天体物理中心);Department of Physics and Astronomy, University of California, Los Angeles(加州大学洛杉矶分校物理与天文系);Technical University of Munich, TUM School of Natural Sciences, Physics Department(慕尼黑工业大学自然科学院物理系);Max Planck Institute for Astrophysics(马克斯·普朗克天体物理学研究所);Space Telescope Science Institute(太空望远镜科学研究所);Sub-Department of Astrophysics, Department of Physics, University of Oxford(牛津大学物理系天体物理子部门)
TDCOSMO XXIX: JWST/NIRSpec IFU Spatially Resolved Kinematics of Three Time-delay Lenses
University of California, Los Angeles(加州大学洛杉矶分校);University of Chicago(芝加哥大学);Independent University, Bangladesh(孟加拉独立大学);University of Oxford(牛津大学);Space Telescope Science Institute(太空望远镜科学研究所);Stony Brook University(石溪大学);Tohoku University(东北大学)
Spatially resolved Halpha maps and sizes of 57 strongly star-forming galaxies at z~1 from 3D-HST: evidence for rapid inside-out assembly of disk galaxies
The stellar velocity anisotropy of strong lensing massive elliptical galaxies and its role in the inference of the Hubble parameter $H_0$ using spatially resolved kinematics
American Museum of Natural History(美国自然历史博物馆);The Graduate Center of the City University of New York(纽约市立大学研究生中心);Lehman College of the CUNY(纽约市立大学雷曼学院);Borough of Manhattan Community College, City University of New York(纽约市立大学曼哈顿社区学院)
Despite the insights gained in the last few years, our knowledge about the formation and evolution scenario for the spheroid-dominated galaxies is still incomplete. New and more powerful cosmological simulations have been developed that together with more precise observations open the possibility of more detailed study of the formation of early-type galaxies (ETGs). The aim of this work is to analyse the assembly histories of ETGs in a $Λ$-CDM cosmology, focussing on the archeological approach given by the mass-growth histories.We inspected a sample of dispersion-dominated galaxies selected fr…
Strongly gravitational lensed quasars can be used to measure the so-called time-delay distance $D_{Δt}$, and thus the Hubble constant $H_0$ and other cosmological parameters. Stellar kinematics of the deflector galaxy play an essential role in this measurement by: (i) helping break the mass-sheet degeneracy; (ii) determining in principle the angular diameter distance $D_{\rm d}$ to the deflector and thus further improving the cosmological constraints. In this paper we simulate observations of lensed quasars with integral field spectrographs and show that spatially resolved kinematics of the de…
MASSIV(VVDS中的SINFONI质量集合巡天)是VLT上的SINFONI积分场单元(IFU)观测到的84个遥远恒星形成星系的样本。这些星系被选择在红移范围0.8 < z < 1.9内,即它们的年龄在30亿到50亿年之间。该样本旨在探测这个宇宙学时代代表性星系的动力学和化学丰度特性。一方面,近距离环境研究表明,大约三分之一的样本涉及重大合并。另一方面,运动学分析表明,42%的样品是旋转盘,与较高的红移样品一致。剩下的58%显示出复杂的运动学,这表明了基于色散的动力学支持,并且这些星系中大约有一半参与了主要的合并。球状体、不松弛的合并残留物或极度湍流的圆盘可能是这种行为的一种解释。此外,空间分辨的金属丰度分析揭示了正梯度,增加了一个星系演化情景的难题。
We investigate possible signatures of halo assembly bias for spectroscopically selected galaxy groups from the GAMA survey using weak lensing measurements from the spatially overlapping regions of the deeper, high-imaging-quality photometric KiDS survey. We use GAMA groups with an apparent richness larger than 4 to identify samples with comparable mean host halo masses but with a different radial distribution of satellite galaxies, which is a proxy for the formation time of the haloes. We measure the weak lensing signal for groups with a steeper than average and with a shallower than average s…
TDCOSMO XXX: Spatially resolved kinematics of the deflectors in time-delay lens systems B1608+656 and SDSSJ1206+4332 from JWST-NIRSpec observation
University of California, Los Angeles(加州大学洛杉矶分校);University of Chicago(芝加哥大学);Independent University, Bangladesh(孟加拉独立大学);University of Oxford(牛津大学);Technical University of Munich(慕尼黑工业大学);Max Planck Institute for Astrophysics(马克斯·普朗克天体物理学研究所)