The COS Absorption Survey of Baryon Harbors: unveiling the physical conditions of circumgalactic gas through multiphase Bayesian ionization modelling
The COS Absorption Survey of Baryon Harbors: unveiling the physical conditions of circumgalactic gas through multiphase Bayesian ionization modelling
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重子港的 COS 吸收调查：通过多相贝叶斯电离模型揭示环星系气体的物理条件
DOI：
10.1093/mnras/staa3544
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发表时间：
2021
影响因子：
4.8
通讯作者：
Werk, Jessica K
中科院分区：
文献类型：
--
作者：
Haislmaier, Karl J;Tripp, Todd M;Katz, Neal;Prochaska, J Xavier;Burchett, Joseph N;O’Meara, John M;Werk, Jessica K
类星体吸收系统包含了星系际和环星系介质的丰度、电离结构和物理条件等丰富的信息。简单的（通常是单相）光电离模型经常被用来解码这些数据。使用五个离散的吸收剂从COS吸收重子港调查（CASBaH），表现出广泛的检测到的离子（例如，Mexico，Sii- Svi，Oii- Ovi，Neviii），我们显示了几个例子，其中单相电离模型不能再现全套测得的柱密度。为了探索能够自洽地解释不同离子的测量和运动学对齐的模型，我们开发了一个贝叶斯多相电离建模框架，该框架通过其独特的物理条件表征离散相，并研究了UV通量场形状，金属丰度和相对丰度的变化。我们的模型需要至少两个（但更倾向于三个）不同的电离阶段，从T = 104 K的光电离气体到T = 105.8K的温热阶段。对于某些离子，一个明显的单一吸收“组件”包括来自一个以上的阶段的贡献，高达30%的Hiis不是来自最低电离阶段。如果我们假设所有的相都是光致电离的，我们就不能在热压平衡中找到解。然而，通过引入更热的碰撞电离相，我们可以实现平衡的压力。最好的模型显示中等的金属丰度，通常具有太阳下的N/α，并且在两种情况下，电离通量场比基准Haardt & Madau UV背景模型更柔和和明亮。
Quasar absorption systems encode a wealth of information about the abundances, ionization structure, and physical conditions in intergalactic and circumgalactic media. Simple (often single-phase) photoionization models are frequently used to decode such data. Using five discrete absorbers from the COS Absorption Survey of Baryon Harbors (CASBaH) that exhibit a wide range of detected ions (e.g. Mgii, Sii– Svi, Oii– Ovi, Neviii), we show several examples where single-phase ionization models cannot reproduce the full set of measured column densities. To explore models that can self-consistently explain the measurements and kinematic alignment of disparate ions, we develop a Bayesian multiphase ionization modelling framework that characterizes discrete phases by their unique physical conditions and also investigates variations in the shape of the UV flux field, metallicity, and relative abundances. Our models require at least two (but favour three) distinct ionization phases ranging fromT≈ 104K photoionized gas to warm-hot phases atT≲ 105.8K. For some ions, an apparently single absorption ‘component' includes contributions from more than one phase, and up to 30 per cent of the Hiis not from the lowest ionization phase. If we assume that all of the phases are photoionized, we cannot find solutions in thermal pressure equilibrium. By introducing hotter, collisionally ionized phases, however, we can achieve balanced pressures. The best models indicate moderate metallicities, often with subsolar N/α, and, in two cases, ionizing flux fields that are softer and brighter than the fiducial Haardt & Madau UV background model.
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影响因子：
3.5
作者：
B. Woodgate;R. Kimble;C. Bowers;S. Kraemer;M. Kaiser;A. Danks;J. Grady;J. Loiacono;M. Brumfield;L. Feinberg;T. Gull;S. Heap;S. Maran;D. Lindler;D. Hood;W. Meyer;C. VanHouten;V. Argabright;Steven Franka;R. L. Bybee;D. Dorn;M. Bottema;R. Woodruff;D. Michika;J. Sullivan;J. Hetlinger;C. W. Ludtke;R. Stocker;A. Delamere;D. Rose;I. Becker;H. Garner;J. Timothy;M. Blouke;C. Joseph;G. Hartig;R. Green;E. Jenkins;J. Linsky;J. Hutchings;H. Moos;A. Boggess;F. Roesler;D. Weistrop
通讯作者：
B. Woodgate;R. Kimble;C. Bowers;S. Kraemer;M. Kaiser;A. Danks;J. Grady;J. Loiacono;M. Brumfield;L. Feinberg;T. Gull;S. Heap;S. Maran;D. Lindler;D. Hood;W. Meyer;C. VanHouten;V. Argabright;Steven Franka;R. L. Bybee;D. Dorn;M. Bottema;R. Woodruff;D. Michika;J. Sullivan;J. Hetlinger;C. W. Ludtke;R. Stocker;A. Delamere;D. Rose;I. Becker;H. Garner;J. Timothy;M. Blouke;C. Joseph;G. Hartig;R. Green;E. Jenkins;J. Linsky;J. Hutchings;H. Moos;A. Boggess;F. Roesler;D. Weistrop
最贫金属阻尼莱曼 α 系统中的 C、N、O 丰度★
DOI：
10.1111/j.1365-2966.2008.12951.x
发表时间：
2007
影响因子：
4.8
作者：
M. Pettini;B. Zych;C. Steidel;F. Chaffee
通讯作者：
F. Chaffee
星系环星系介质的结构：NGC 1097 周围的冷吸积流
DOI：
10.3847/0004-637x/826/1/50
发表时间：
2016
期刊：
The Astrophysical Journal
影响因子：
--
作者：
D. Bowen;D. Chelouche;E. Jenkins;T. Tripp;M. Pettini;D. York;B. Frye
通讯作者：
B. Frye
DOI：
10.1086/587486
发表时间：
2007-06
期刊：
The Astrophysical Journal Supplement Series
影响因子：
--
作者：
T. Tripp;K. Sembach;D. Bowen;B. Savage;E. Jenkins;N. Lehner;P. Richter
通讯作者：
T. Tripp;K. Sembach;D. Bowen;B. Savage;E. Jenkins;N. Lehner;P. Richter
影响因子：
6.5
作者：
P. Richter;C. Ledoux;P. Petitjean;J. Bergeron
通讯作者：
P. Richter;C. Ledoux;P. Petitjean;J. Bergeron