The Low-Redshift Lyman Continuum Survey. Unveiling the ISM properties of low-$z$ Lyman continuum emitters
Alberto Saldana-Lopez, Daniel Schaerer, John Chisholm, Sophia R. Flury, Anne E. Jaskot, Gábor Worseck, Kirill Makan, Simon Gazagnes, Valentin Mauerhofer, Anne V… 展开作者
Alberto Saldana-Lopez, Daniel Schaerer, John Chisholm, Sophia R. Flury, Anne E. Jaskot, Gábor Worseck, Kirill Makan, Simon Gazagnes, Valentin Mauerhofer, Anne Verhamme, Ricardo O. Amorín, Harry C. Ferguson, Mauro Giavalisco, Andrea Grazian, Matthew J. Hayes, Timothy M. Heckman, Alaina Henry, Zhiyuan Ji, Rui Marques-Chaves, Stephan R. McCandliss, M. S. Oey, Göran Östlin, Laura Pentericci, Trinh X. Thuan, Maxime Trebitsch, Eros Vanzella, Xinfeng Xu
备注:
30 pages, 16 figures, 3 tables; accepted for publication in Astronomy and Astrophysics on December 16, 2021. Tables A1 to A4 are part of the LzLCS science products and will be publicly available in a dedicated website
Combining 66 ultraviolet (UV) spectra and ancillary data from the Low-Redshift Lyman Continuum Survey (LzLCS) and 23 LyC observations by earlier studies, we form a statistical sample of star-forming galaxies at $z \sim 0.3$ to study the role of the cold interstellar medium (ISM) gas in the leakage of ionizing radiation. We first constrain the massive star content (ages and metallicities) and UV attenuation, by fitting the stellar continuum with a combination of simple stellar population models. The models, together with accurate LyC flux measurements, allow to determine the absolute LyC photon escape fraction for each galaxy ($f_{\rm esc}^{\rm abs}$). We measure the equivalent widths and residual fluxes of multiple HI and low-ionization state (LIS) lines, and the geometrical covering fraction adopting the picket-fence model. The $f_{\rm esc}^{\rm abs}$ spans a wide range, with a median (0.16, 0.84 quantiles) of 0.04 (0.02, 0.20), and 50 out of the 89 galaxies detected in the LyC. The HI and LIS line equivalent widths scale with the UV luminosity and attenuation, and inversely with the residual flux of the lines. The HI and LIS residual fluxes are correlated, indicating that the neutral gas is spatially traced by the LIS transitions. We find the observed trends of the absorption lines and the UV attenuation are primarily driven by the covering fraction. The non-uniform gas coverage demonstrates that LyC photons escape through low-column density channels in the ISM. The equivalent widths and residual fluxes of the UV lines strongly correlate with $f_{\rm esc}^{\rm abs}$: strong LyC leakers show weak absorption lines, low UV attenuation, and large Ly$α$ equivalent widths. We finally show that simultaneous UV absorption line and dust attenuation measurements can predict, on average, the escape fraction of galaxies and the method can be applied to galaxies across a wide redshift range.
The Lyman Alpha Reference Sample: V. The impact of neutral ISM kinematics and geometry on Lyman Alpha escape
我们提出了高分辨率的远紫外光谱的莱曼阿尔法参考样本的14个星系,强烈的恒星形成星系在低红移($0.028 < z < 0.18$)的样本。我们比较派生的属性来自多波段成像和21厘米HI干涉和单碟观测,以及档案光学SDSS光谱的全球性。除了莱曼$α$线,光谱包含一些金属吸收功能,使我们能够探测的中性ISM的运动学和评估的光学深度和覆盖率的中性介质作为视线速度的函数。此外,我们展示了如何结合系统速度的精确测定和良好的Ly $α$光谱,将单独的团块一起完全覆盖背景源的模型与Heckman等人(2011)命名的“栅栏”模型区分开来。我们发现,没有一个单一的效果占主导地位的管理赖氨酸$α$辐射转移和逃逸。在我们的样本中,Ly $α$逃逸与$\lesssim 0.9$的最大速度分仓覆盖分数和$\gtrsim 50$ km s $^{-1}$的批量流出速度相吻合,尽管一些星系显示出这些特征,但Ly $α$逃逸很少或根本没有。我们发现,Ly $α$峰值速度,在可用的情况下,是不一致的一个强大的后向散射分量,而是与一个简单的模型的内在发射线覆盖的蓝移吸收轮廓从外流风。最后,我们发现H $α$等效宽度和最大速度分组覆盖因子之间存在很强的相关性,并提出了一个启发式解释模型。
Lyman-alpha line and continuum radiative transfer in a clumpy interstellar medium
目的:我们的目标是研究非均匀星际介质(ISM)对星暴星系中莱曼α(Lya)线的强度和形状的影响。研究方法:利用我们的三维Monte Carlo Lya辐射传输程序,研究了Lya、紫外和光学连续谱光子在中性氢和尘埃的均匀壳层和团壳层中围绕中心源的辐射转移。我们的模拟预测的Lya和连续逃逸分数,Lya等效宽度EW(Lya),Lya线的轮廓和它们的依赖于气体的几何形状和主要的输入物理参数。结果如下:ISM的块状被发现有强烈的影响Lya线辐射转移,需要一个强烈的依赖性Lya线的紧急功能(逃逸分数,EW(Lya))的ISM形态。虽然cloudies和灰尘ISM出现更透明的辐射(线和连续)相比,一个相等的均匀ISM的相等的灰尘光学深度,我们发现,Lya光子,在一般情况下,仍然比紫外线连续辐射衰减。因此,观察到的Lya等效宽度(EWobs(Lya))是低于本征的(EWint(Lya)),几乎所有的clusionism配置考虑。然而,在特殊条件下,Lya光子比连续体更容易逃逸,从而导致增强的EWobs(Lya)。要实现这一点,需要ISM几乎是静止的(星系外流速度小于200 km/s),极其稠密(在HI中,星系团和星系团间介质的密度差大于10^7),并且尘埃非常多(E(B-V)> 0.30)。当满足这些条件时,出现的Lya线轮廓显示没有速度移动和小的不对称性。考虑到不对称性和速度的变化,通常观察到的…
Unveiling the roles of thermal and nonthermal processes in the ISM & IGM structure formation and evolution of galaxies with SKAO
Institute for Research in Fundamental Sciences (IPM)(伊朗基础科学研究所);Xinjiang Astronomical Observatory, CAS(中国科学院新疆天文台);National Radio Astronomy Observatory(美国国家射电天文台);Netherlands Institute for Radio Astronomy(荷兰射电天文研究所);University of Groningen(格罗宁根大学);SKA Observatory(平方公里阵列望远镜观测站);Chalmers University of Technology(查尔姆斯理工大学);University of Hamburg(汉堡大学);University of Virginia(弗吉尼亚大学)
Unveiling the Ionized and Neutral ISM at z > 10 : The Origin of [O III] /[C II] Ratios from a Sub-parsec Resolution Radiative Transfer Simulation
Center for Computational Astrophysics, Flatiron Institute(计算天体物理学中心,弗拉廷研究所);Department of Physics, The University of Tokyo(东京大学物理学系);Faculty of Science, Hokkaido University(北海道大学理学部);Waseda Research Institute for Science and Engineering, Faculty of Science and Engineering, Waseda University(早稻田大学理工学研究科理工学部理工学研究院);Department of Physics, School of Advanced Science and Engineering, Faculty of Science and Engineering, Waseda University(早稻田大学理工学部先进理工学研究科物理学系);Department of Astronomy, University of Maryland, College Park(马里兰大学天文学系)
Unveiling Hidden Lyman Alpha Emitters in the DESI DR1 Data
Graduate Institute of Astrophysics, National Taiwan University(台湾大学天文研究所);Department of Physics and Center for Theoretical Physics, National Taiwan University(台湾大学物理系暨理论物理中心);Institute of Astronomy and Astrophysics, Academia Sinica(中央研究院天文及天文物理研究所);Department of Astronomy and Astrophysics, University of California at Santa Cruz(加州大学圣克鲁斯分校天文与天体物理系);University of California Observatories, Lick Observatory(加州大学天文台利克天文台);Kavli Institute for the Physics and Mathematics of the Universe, University of Tokyo(东京大学卡弗里宇宙物理数学研究所);Division of Science, National Astronomical Observatory of Japan(日本国立天文台理学科);Institute for Multi-messenger Astrophysics and Cosmology, Department of Physics, Missouri University of Science and Technology(密苏里科技大学物理系多信使天体物理学与宇宙学研究所)
The Sunburst Arc with JWST. IV. The importance of interaction, turbulence, and feedback for Lyman-continuum escape
Stockholm University(斯德哥尔摩大学);International Space Science Institute(国际空间科学研究所);Center for Research and Exploration in Space Science and Technology, NASA/GSFC(NASA戈达德太空飞行中心空间科学与技术研究实验中心);NASA Goddard Space Flight Center(美国宇航局戈达德太空飞行中心);California Institute of Technology(加州理工学院);Steward Observatory, University of Arizona(亚利桑那大学斯蒂沃德天文台)
Disentangling the galactic and intergalactic components in 313 observed Lyman-alpha line profiles between redshift 0 and 5
Observatori Astronòmic de la Universitat de València(瓦伦西亚大学天文台);Departament d’Astronomia i Astrofísica, Universitat de València(瓦伦西亚大学天文学与天体物理学系);Universität Heidelberg(海德堡大学);Max Planck Institute for Astrophysics(马克斯·普朗克天体物理学研究所);Tsinghua University(清华大学);IFCA-CSIC/Universitat de València(坎塔布里亚物理研究所CSIC-瓦伦西亚大学联合单位);Instituto de Física de Cantabria (CSIC-UC)(坎塔布里亚物理研究所)
Unveiling the Cosmic Dawn with SHARP: Probing extended Lyman-$α$ nebulae in a Universe less than 600 Myr old
INAF-IASF Milano(意大利国家天体物理研究所米兰天文物理研究所);INAF – Osservatorio Astronomico di Roma(意大利国家天体物理研究所罗马天文台);Department of Mathematics and Physics, Roma Tre University(罗马三大大学数学与物理系);INAF–OAT, Osservatorio Astronomico di Trieste(意大利国家天体物理研究所的里雅斯特天文台)
PRISMS. U37126, a very blue, ISM-naked starburst at z=10.255 with nearly 100% Lyman continuum escape fraction
University of Geneva(日内瓦大学);Centro de Astrobiología (CAB), CSIC-INTA(天体生物学中心 (CAB),西班牙国家科学技术研究委员会-国家航空航天技术研究所);European Space Agency (ESA)(欧洲空间局 (ESA));Space Telescope Science Institute(哈勃太空望远镜科学研究所);Indiana University(印第安纳大学);Universidad Complutense de Madrid(马德里康普顿斯大学);Leiden University(莱顿大学);INAF – Osservatorio Astronomico di Roma(意大利国家天体物理研究所-罗马天文台);University of Groningen(格罗宁根大学)
M^3D: Mosaicking M33 with MUSE datacubes I. Unveiling the diversity of HII regions in M33 with MUSE
Università di Firenze(佛罗伦萨大学);Center for Astrophysics | Harvard & Smithsonian(哈佛史密森天体物理中心);National Radio Astronomy Observatory(国家射电天文台);University of Zagreb(萨格勒布大学);Ecole Polytechnique Federale de Lausanne(洛桑联邦理工学院)
The SPHINX public data release. II. Using low-ionisation absorption lines and dust attenuation to predict Lyman continuum escape
Kapteyn Astronomical Institute, University of Groningen(格罗宁根大学卡普坦天文研究所);Centre de Recherche Astrophysique de Lyon UMR5574, Univ Lyon1, ENS de Lyon, CNRS(里昂天体物理研究中心);Observatoire de Genève, Université de Genève(日内瓦大学日内瓦天文台);Aix Marseille Univ., CNRS, CNES, Laboratoire d’Astrophysique de Marseille(马赛天体物理实验室);Department of Astronomy, The University of Texas at Austin(德克萨斯大学奥斯汀分校天文学系);Cosmic Frontier Center, The University of Texas at Austin(德克萨斯大学奥斯汀分校宇宙前沿中心);Department of Astronomy, Oskar Klein Centre, Stockholm University(斯德哥尔摩大学奥斯卡·克莱因中心天文学系);LUX, Observatoire de Paris, Université PSL, Sorbonne Université, CNRS(巴黎天文台);Department of Astronomy, Yonsei University(延世大学天文学系)