Planetary and Space Science最新文献_第8页

Diurnal temperature cycle models and performances on Martian surface using in-situ and satellite data 基于原位和卫星数据的火星表面日温度循环模型及其性能

IF 1.8 4区物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS

Planetary and Space Science

Pub Date : 2025-03-20 DOI: 10.1016/j.pss.2025.106100

Yu Wang , Shuanggen Jin

Martian surface temperature and its diurnal variations play a key role in studying Mars land-atmosphere interactions. However, accurate Diurnal Temperature Cycle (DTC) models on Martian surface are presently absent or have large uncertainties. This study aims to construct semi-empirical DTC models of the Martian surface and address this gap by assessing their performances. Utilizing in-situ data collected by the Viking 1, Insight, Perseverance, and Curiosity rovers, we assess the performances of these DTC models by examining overall accuracy, daily precision, error rates across various hours, and effectiveness during different Martian seasons. The parameters of the models gain insights into the seasonal variations of surface temperature on Mars. Additionally, we conduct a focused analysis on the parameter-reduction approaches (PRAs) to assess the potential suitability of DTC models with the constraints of limited satellite observations available for Mars. Results indicate that the DTC models can effectively capture the diurnal surface temperature variations on Mars, with an overall error ranging from 0.74 to 2.28 K. Among the DTC models, the DMT24 model developed in this study shows the superior performance and can reproduce the slow and smooth increase around sunrise and maintain accuracy during nighttime periods. The DTC models can well capture the diurnal surface temperature cycle on Mars using limited satellite data based on suitable PRAs. This study offers valuable references for utilizing global DTC models on Mars.

火星表面温度及其日变化在研究火星陆地-大气相互作用中起着关键作用。然而，精确的火星表面日温度循环（DTC）模型目前缺乏或有很大的不确定性。本研究旨在构建火星表面的半经验DTC模型，并通过评估其性能来解决这一空白。利用海盗1号、洞察号、毅力号和好奇号火星车收集的现场数据，我们通过检查总体精度、每日精度、不同小时的错误率以及不同火星季节的有效性来评估这些DTC模型的性能。这些模型的参数可以深入了解火星表面温度的季节性变化。此外，我们对参数约简方法（pra）进行了重点分析，以评估DTC模型在有限的火星卫星观测约束下的潜在适用性。结果表明，DTC模型可以有效地捕捉火星地表温度的日变化，总体误差在0.74 ~ 2.28 K之间。在DTC模型中，本研究开发的DMT24模型表现出较好的性能，可以再现日出前后缓慢平稳的增长，并在夜间保持精度。DTC模型可以利用有限的卫星数据，基于合适的pra，很好地捕捉火星表面的日温度周期。该研究为在火星上应用全球DTC模型提供了有价值的参考。

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引用次数: 0

Key structural characteristics of porous layers in diffusion modelling: A study on polydispersity, shape, and hierarchy 扩散模型中多孔层的关键结构特征：多分散性、形状和层次的研究

IF 1.8 4区物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS

Planetary and Space Science

Pub Date : 2025-03-15 DOI: 10.1016/j.pss.2025.106078

Volodymyr Reshetnyk , Igor Luk’yanyk , Yuri Skorov , Yevgen Grynko , Wolfgang Macher , Christian Schuckart , Yuhui Zhao , Jürgen Blum

In this study, we explored various open-source models for generating porous media. These models enabled us to examine different types of porous beds, including layers of polydisperse spheres with various size distributions, layers of porous aggregates – either fragments of parent porous layers or those formed during the agglomeration of polydisperse spheres – and layers of non-spherical particles with both regular and random shapes. Through extensive simulations, we derived estimates for the averaged structural characteristics of the model layers. These estimates will be utilized in macroscopic models to study heat diffusion and the sublimation of products in the near-surface layer of a cometary nucleus. Our findings revealed significant differences between the obtained estimates and those previously made for layers of monodisperse spheres, underscoring the importance of this research. We also compared numerical results with theoretical formulas for layers of monodisperse spheres.

在这项研究中，我们探索了各种开源模型来生成多孔介质。这些模型使我们能够研究不同类型的多孔层，包括具有不同尺寸分布的多分散球体层，多孔聚集体层-要么是母体多孔层的碎片，要么是在多分散球体聚集过程中形成的-以及具有规则和随机形状的非球形颗粒层。通过广泛的模拟，我们对模式层的平均结构特征进行了估计。这些估计将在宏观模型中用于研究彗星核近表层的热扩散和产物升华。我们的发现揭示了所获得的估计值与先前对单分散球体层所做的估计值之间的显着差异，强调了本研究的重要性。我们还将单分散球层的数值计算结果与理论计算公式进行了比较。

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引用次数: 0

Astrometric performance of the five major uranian satellites using a narrow-band Methane filter 五颗主要的天王星卫星使用窄带甲烷过滤器的天文测量性能

IF 1.8 4区物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS

Planetary and Space Science

Pub Date : 2025-03-14 DOI: 10.1016/j.pss.2025.106085

X.Q. Fang , Q.Y. Peng , X. Lu , B.F. Guo

During ground-based observations of satellites near a bright planet, the satellite images are often affected by the planet’s halo, introducing significant uncertainty in their astrometric positions. To address this issue, we employed a narrow-band methane filter for observations of the five major Uranian satellites, which makes them easily discernible on CCD frames without requiring halo removal procedures. We systematically evaluated the astrometric performance of this Methane filter and compared it to that of the commonly used Clear and Cousins-I filters. Totally, the positional precision for most of the four brightest satellites is approximately 30 mas in both right ascension and declination, comparable to the Cousins-I filter and superior to the Clear filter. On the other hand, the faint satellite Miranda achieves a precision of better than 80 mas after image stacking in the methane band images. Based on our experiments, we recommend using the Methane filter for observing objects with an apparent visual magnitude brighter than 15, as it offers a sufficient signal-to-noise ratio (SNR) of approximately 55 within a reasonable exposure time of 200 s using a 0.8 m telescope.

在对明亮行星附近的卫星进行地面观测时，卫星图像往往会受到行星光晕的影响，从而给它们的天体测量位置带来很大的不确定性。为了解决这个问题，我们采用了一种窄带甲烷滤光片来观测天王星的五颗主要卫星，这种滤光片可以在 CCD 图像上轻松辨别这些卫星，而不需要进行光晕去除程序。我们系统地评估了这种甲烷滤光片的天体测量性能，并将其与常用的Clear和Cousins-I滤光片进行了比较。从总体上看，四颗最亮卫星中的大多数在赤经和赤纬上的定位精度都大约为30mas，与Cousins-I滤光片相当，优于Clear滤光片。另一方面，昏暗卫星米兰达在甲烷波段图像叠加后的精度超过了 80mas。根据我们的实验，我们建议在观测视星等亮度大于 15 的天体时使用甲烷滤光片，因为使用 0.8 米望远镜，在 200 秒的合理曝光时间内，甲烷滤光片可以提供约 55 的足够信噪比（SNR）。

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引用次数: 0

Effective feature matching of high-resolution planetary orbiter images based on optimized image partitioning and rapid local correspondence 基于优化图像分割和快速局部对应的高分辨率行星轨道图像有效特征匹配

IF 1.8 4区物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS

Planetary and Space Science

Pub Date : 2025-03-13 DOI: 10.1016/j.pss.2025.106091

Lin Xue , Zhen Ye , Dayong Liu , Shijie Liu , Rong Huang , Huan Xie , Yongjiu Feng , Beibei Guo , Yusheng Xu , Xiaohua Tong

Feature matching of high-resolution planetary orbiter images (HRPOIs) plays a significant role in photogrammetric mapping and three-dimensional modeling, which is particularly challenging due to their narrow fields of view, similar surface textures, and large sizes. Neither directly using matching methods nor combining them with traditional strategies can fully overcome the matching challenges posed by HRPOIs. In this study, a feature matching scheme specifically designed for HRPOIs is proposed, which integrates an optimized image partitioning method for overlapping areas and establishes rapid local correspondence between image blocks. A row-to-column grid partitioning method is developed to ensure the range of the partitioned image blocks better align with the boundaries of the complex overlapping areas. Subsequently, the relative positional relationships of the extreme coordinate points in the row direction within the overlapping areas of image pairs are determined to rapidly establish local correspondence between the partitioned images, providing local geometric constraints and avoiding interference caused by redundant features. Moreover, a multilevel efficiency optimization strategy, which combines Graphics Processing Unit (GPU) acceleration with distributed parallelism to enhance the matching efficiency, is designed. Experiments on data derived from the Lunar Reconnaissance Orbiter Narrow Angle Camera (LRO NAC) and Mars Reconnaissance Orbiter Context Camera (MRO CTX) were conducted to validate the feasibility and reliability. The experimental results demonstrate that the proposed scheme effectively overcomes the challenges faced when matching HRPOIs, outperforming several mainstream photogrammetric software in terms of both matching accuracy and efficiency.

高分辨率行星轨道图像（hrpoi）的特征匹配在摄影测量制图和三维建模中发挥着重要作用，但由于其狭窄的视场、相似的表面纹理和较大的尺寸，这一工作尤其具有挑战性。无论是直接使用匹配方法，还是与传统策略相结合，都不能完全克服hrpoi的匹配挑战。本研究提出了一种专门针对hrpoi的特征匹配方案，该方案集成了一种优化的重叠区域图像分割方法，并在图像块之间快速建立局部对应关系。提出了一种行到列的网格分割方法，以保证分割后的图像块范围更好地与复杂重叠区域的边界对齐。随后，确定图像对重叠区域内行方向极值坐标点的相对位置关系，快速建立分割图像之间的局部对应关系，提供局部几何约束，避免冗余特征带来的干扰。在此基础上，设计了一种将GPU加速与分布式并行性相结合的多级效率优化策略，以提高匹配效率。利用月球勘测轨道飞行器窄角相机（LRO NAC）和火星勘测轨道飞行器背景相机（MRO CTX）的数据进行实验，验证了该方法的可行性和可靠性。实验结果表明，该方案有效地克服了hrpoi匹配所面临的挑战，在匹配精度和效率方面均优于几种主流摄影测量软件。

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引用次数: 0

Robust automatic crater detection at all latitudes on Mars with deep-learning 强大的自动陨石坑探测在火星上的所有纬度与深度学习

IF 1.8 4区物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS

Planetary and Space Science

Pub Date : 2025-03-11 DOI: 10.1016/j.pss.2025.106053

L. Martinez , F. Andrieu , F. Schmidt , H. Talbot , M.S. Bentley

Understanding the distribution and characteristics of impact craters on planetary surfaces is essential for unraveling geological processes and the evolution of celestial bodies. Several machine learning and AI-based approaches have been proposed to detect craters on planetary surface images automatically. However, designing a robust tool for an entire complex planet such as Mars, is still an open problem. This article presents a novel approach using the Faster Region-based Convolutional Neural Network (Faster R-CNN) for such a detection. The proposed method involves the pre-processing, training and crater detection steps, which are especially designed for robustness regarding latitude and complex geomorphological features. The objectives of this studies are to (i) be robust at all latitudes and (ii) for

\geq 1

km diameter crater sizes. (iii) To propose an open-source and re-usable algorithm that (iv) only needs an image to run. Extensive experiments on high-resolution planetary imagery demonstrate excellent performances with an average precision

{AP}_{50} > 0.82

with an intersection over union criterion

IoU \geq 0.5

, irrespective of crater scale. For mid and high latitudes (higher than 48°north and south), performance decreases down to

{AP}_{50} \sim 0.7

, which is still better than the current state of the art. Loss of performance is mostly due to strong shadowing effects. Our results also highlight the versatility and potential of our robust model for automating the analysis of craters across different celestial bodies. The automated crater detection tool presented in this article is publicly available as open-source and holds great promise for future scientific research of space exploration missions.

了解行星表面陨石坑的分布和特征对于揭示地质过程和天体演化至关重要。已经提出了几种基于机器学习和人工智能的方法来自动检测行星表面图像上的陨石坑。然而，为像火星这样的整个复杂星球设计一个强大的工具，仍然是一个悬而未决的问题。本文提出了一种使用更快的基于区域的卷积神经网络（Faster R-CNN）进行这种检测的新方法。该方法包括预处理、训练和陨石坑检测步骤，特别针对纬度和复杂地貌特征设计了鲁棒性。本研究的目标是(i)在所有纬度上都具有鲁棒性，（ii）对于直径≥1公里的陨石坑大小。（iii）提出一个开源和可重用的算法，（iv）只需要一个映像来运行。在高分辨率行星图像上进行的大量实验表明，无论陨石坑规模如何，平均精度AP50>；0.82，相交于联合准则IoU≥0.5，都具有出色的性能。在中纬度和高纬度地区（高于南北48°），性能下降到AP50 ~ 0.7，但仍优于目前的技术水平。性能损失主要是由于强烈的阴影效应。我们的结果也突出了我们的强大模型的多功能性和潜力，可以自动分析不同天体上的陨石坑。本文中介绍的自动陨石坑探测工具是公开的开源工具，对未来太空探索任务的科学研究有很大的希望。

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引用次数: 0

Three-dimensional simulation of surface charging in meteorite craters on rotating asteroids 旋转小行星陨石坑表面充注的三维模拟

IF 1.8 4区物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS

Planetary and Space Science

Pub Date : 2025-03-11 DOI: 10.1016/j.pss.2025.106089

Zhiying Song, Zhigui Liu, Ronghui Quan

Meteorite craters on the asteroid surface obstruct the horizontal flow of solar wind, forming a plasma wake that modulates the particle fluxes and the electrostatic environment far downstream. In this study, the surface charging properties of asteroids with nontrivial terrain are simulated on the basis of the neural network and the finite element method. Key factors such as the location, size and depth-to-width ratio of craters are all considered. Under normal conditions, as the latitude of the crater increases, the potential variation at its floor during a rotation gradually becomes smoother, finally stabilizing around −27.5 V with minor fluctuations when the crater approaches the poles. Because of the diverging motions of electrons and the less deflected trajectories of ions, near the terminator, the surface potential variation within craters with low depth-to-width ratios primarily depends on ion density, which decreases with increasing depth. In contrast, for craters with a depth-to-width ratio greater than 0.5, the potential differences at the crater floor arise mainly from the electron distribution. While the surface potential appears indifferent to changes in crater size, only during solar storms, the floor of large-scale craters, such as those with a diameter of 800 m, perform a 26.78 V decrease in potential compared to small craters of 50 m. Both studies of localized plasma flow field and the surface charging phenomenon of asteroids have substantial influence on the future safe landing and exploration missions.

小行星表面的陨石坑阻碍了太阳风的水平流动，形成了等离子体尾流，调节了粒子通量和远下游的静电环境。本研究基于神经网络和有限元方法，对具有非平凡地形的小行星表面电荷特性进行了模拟。关键因素，如位置，大小和深宽比的陨石坑都考虑在内。在正常情况下，随着陨石坑纬度的增加，其底部在旋转过程中的电位变化逐渐变得平缓，最终稳定在−27.5 V左右，当陨石坑接近两极时波动较小。由于电子的发散运动和离子的较少偏转轨迹，在终结点附近，低深宽比陨石坑内的表面电位变化主要取决于离子密度，离子密度随深度的增加而减小。相比之下，对于深宽比大于0.5的陨石坑，坑底电位差主要来自于电子分布。表面电位与陨石坑大小的变化无关，只有在太阳风暴期间，大型陨石坑的底部，如直径为800 m的陨石坑，与直径为50 m的小陨石坑相比，电位下降26.78 V。局部等离子体流场和小行星表面充电现象的研究对未来的安全着陆和探测任务具有重要影响。

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引用次数: 0

Three dimensional (3-D) density structures for the lunar mascons beneath impact basins and its implication for the evolution of the moon 撞击盆地下月球岩浆的三维（3-D）密度结构及其对月球演化的影响

IF 1.8 4区物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS

Planetary and Space Science

Pub Date : 2025-03-08 DOI: 10.1016/j.pss.2025.106090

Jianguo Yan , Brave Manda , Feng Liang , Chikondi Chisenga , Zhiyong Xiao , Qingyun Deng

Lunar mascons are thought to be caused by mantle uplift. We study lunar mascons to reveal their high-resolution 3D density structure based on the depth-weighting gravity inversion method. The inversion results show that mascons exhibit annular density anomalies, but the roots of mascons on the lunar nearside are shallower than those at the farside, which is consistent with the thicker crust at the lunar farside. Inner density heterogeneity for mascons is also observed in the density model, indicating evidence of the possible vertical and horizontal isostatic readjustment. Based on the density models, we suggest that the crustal asymmetry on the Moon observed in lunar basin thickness, size, and diameter is partly caused by mascon density heterogeneity located in the mantle that promoted mantle uplift after impact cratering, as observed in the recovered density models for lunar mascon.

月球上的mascons被认为是由地幔隆起引起的。基于深度加权重力反演方法，研究月球表面的高分辨率三维密度结构。反演结果表明，月球近侧的泥岩呈现出环形密度异常，但泥岩的根部较远侧浅，这与月球远侧地壳较厚相一致。在密度模型中也观察到mascons的内部密度非均匀性，表明可能存在垂直和水平均衡调整的证据。基于密度模型，我们认为月球盆地厚度、大小和直径的地壳不对称性部分是由于位于地幔的mascon密度非均匀性造成的，而mascon密度非均匀性促进了撞击后的地幔隆起，正如恢复的月球mascon密度模型所显示的那样。

引用次数: 0

Relaxation probe measurement in the Earth's and Titan's atmospheres: Effect of shadow 地球和土卫六大气中的松弛探测器测量：阴影的影响

IF 1.8 4区物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS

Planetary and Space Science

Pub Date : 2025-03-04 DOI: 10.1016/j.pss.2025.106088

John D. de Boer , R. Godard , José J. López-Moreno , Gregorio J. Molina-Cuberos

In this work, we investigate the shadowing effect of the boom and the gondola on electrical conductivity measurement in the stratosphere using a Relaxation Probe (RP). By taking the examples of the terrestrial flight for the Huygens experiment and the Huygens mission to Titan, our numerical simulations demonstrate that this effect should be taken into account, particularly for the resistance of the electrode-ionized medium during both the apogee and descent of a balloon. The fact that a signal seems a perfect exponential does not allow one to accept the hypothesis of a measurement at face value, and a correction factor should be applied. Our numerical simulations show that the resistance and the capacitance are almost constant, independent of the potential of the electrode. This makes the correction of the data an easy task. This analysis was carried out using finite element methods to model a complex electrode-boom-gondola geometry. In our model, the potential around the electrode-boom-gondola system is described by a Laplace equation, and this corresponds well to the stratospheric environment. We shall emphasize the crucial importance of estimating the floating potential of the gondola during a flight from the relaxation data of the potential. From our numerical simulations, it appears that the resistance may be too high by a factor 1.72, depending of course on the length of the boom. Also, the measurement of the positive ions by the RP for the Huygens mission around Titan does not seem too reliable. In this case, we found a heavy shadowing effect of the gondola. We hope that this work will aid in the optimal design of future planetary missions, taking into account the length of boom and, given the constraints of a mission, whether the boom should be an insulator, or a conducting body.

在这项工作中，我们研究了使用松弛探针（RP）测量平流层中吊杆和吊舱的阴影效应。以惠更斯号地面飞行实验和惠更斯号土卫六任务为例，我们的数值模拟表明，这种影响应该被考虑在内，特别是在气球远地点和下降时电极电离介质的阻力。信号似乎是一个完美的指数，这一事实不允许人们接受表面上的测量假设，并且应该应用校正因子。我们的数值模拟表明，电阻和电容几乎是恒定的，与电极的电位无关。这使得更正数据成为一项容易的任务。采用有限元方法对复杂的电极-吊杆-吊篮几何结构进行了分析。在我们的模型中，电极-吊杆-吊篮系统周围的电势用拉普拉斯方程描述，这与平流层环境很好地对应。我们将强调根据势能的弛豫数据估计吊篮在飞行过程中的浮动势能的关键重要性。从我们的数值模拟来看，阻力可能过高了1.72倍，当然这取决于吊杆的长度。此外，惠更斯号环绕土卫六的任务中，RP对正离子的测量似乎也不太可靠。在这种情况下，我们发现了贡多拉的严重阴影效应。我们希望这项工作将有助于未来行星任务的最佳设计，考虑到臂架的长度，并考虑到任务的限制，臂架应该是绝缘体还是导电体。

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引用次数: 0

An energy balance climate model for Mars represented by 4002 Goldberg polyhedrals with applications to ground ice re-distribution driven by obliquity cycles 以4002 Goldberg多面体为代表的火星能量平衡气候模式，应用于由倾角循环驱动的地面冰再分布

IF 1.8 4区物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS

Planetary and Space Science

Pub Date : 2025-03-04 DOI: 10.1016/j.pss.2025.106077

Robert Olszewski , Piotr Pałka , Agnieszka Wendland , Alison F.C. Bridger , Melinda A. Kahre , Christopher P. McKay

We have developed a surface energy balance model for Mars based on representing the surface of Mars with a Goldberg polyhedral of 4002 cells. The approach using discretization of space with Goldberg polygons made it possible not only to obtain homogeneous spatial resolution but also the absence of a singularity at the poles in the model. In addition to the radiation terms, the surface energy balance includes CO₂ condensation and evaporation, the diffusive exchange of heat between cells, heat exchange with the subsurface, and a representation of the large-scale transport of heat from the equator to pole. We validate the model by comparing model results to the Viking lander temperature and pressure data. The model results are within 10% in both temperature and pressure compared to both Viking 1 and Viking 2 landers. We also compare to current Mars GCMs. Our baseline model has a total exchangeable CO₂ mass equivalent to 700 Pa and a mean annual surface temperature of 215.9 K. We use the baseline model to investigate the effects of changes in obliquity on climate. With all other model parameters held constant we find that as the obliquity increases above ∼30° the mean annual vapor density of ground ice at the poles becomes greater than at the equator implying a net transfer of water from pole to equator. We also find there is 95% consistency with the MCD model in CO₂ ice formation. The Mars polyhedral model has high spatial resolution but is still computationally efficient and can be used to simulate a variety of processes on Mars, at present or in past and future epochs.

基于4002个细胞的哥德堡多面体表示火星表面，建立了火星表面能量平衡模型。利用Goldberg多边形的空间离散化方法不仅可以获得均匀的空间分辨率，而且可以在模型的极点处不存在奇点。除了辐射项外，地表能量平衡还包括CO2冷凝和蒸发、细胞间的扩散热交换、与地下的热交换以及从赤道到极地的大规模热量输送。我们通过将模型结果与海盗号着陆器的温度和压力数据进行比较来验证模型。与海盗1号和海盗2号着陆器相比，该模型的结果在温度和压力上都在10%以内。我们还比较了目前的火星gcm。我们的基线模型的总可交换CO2质量相当于700 Pa，年平均地表温度为215.9 K。我们使用基线模型来研究倾角变化对气候的影响。在所有其他模式参数保持不变的情况下，我们发现，当倾角增加到~ 30°以上时，极地地面冰的年平均蒸汽密度大于赤道，这意味着水从极地向赤道的净转移。我们还发现CO2冰形成与MCD模型有95%的一致性。火星多面体模型具有很高的空间分辨率，但计算效率仍然很高，可以用来模拟火星上当前或过去和未来时代的各种过程。

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引用次数: 0

Production of carbon samples with extreme physical conditions using intense heavy ion beams at the facility for antiprotons and ion research: Application to planetary physics research 在反质子和离子研究设施中使用强重离子束在极端物理条件下生产碳样品：在行星物理研究中的应用

IF 1.8 4区物理与天体物理 Q3 ASTRONOMY & ASTROPHYSICS

Planetary and Space Science

Pub Date : 2025-02-26 DOI: 10.1016/j.pss.2025.106074

N.A. Tahir , V. Bagnoud , P. Neumayer , A.R. Piriz , S.A. Piriz

The possibility of existence of carbon-rich-planets makes it important to study High Energy States of carbon in order to understand the internal structure of such planets. In this paper, we present two-dimensional hydrodynamic simulations of a low-entropy compression of a carbon sample that is enclosed in a high-Z cylindrical shell that is driven by a high intensity uranium beam. The considered beam parameters are the ones that will be available at the accelerator facility, named, FAIR, at Darmstadt. This study has shown that the carbon sample can be compressed to 2 to 3 times solid density and ultra-high pressures are achieved. The temperature, on the other hand, remains relatively low. These are the typical physical conditions that are expected to exist in the planetary interiors. An experimental study of the thermophysical and transport properties of such samples will significantly improve our knowledge about formation and evolution of different type of planets.

富碳行星存在的可能性使得研究碳的高能态以了解这类行星的内部结构变得非常重要。在本文中，我们提出了低熵压缩碳样品的二维流体动力学模拟，该碳样品被封闭在高z圆柱壳中，由高强度铀束驱动。所考虑的光束参数将在达姆施塔特名为FAIR的加速器设施中使用。这项研究表明，碳样品可以被压缩到固体密度的2到3倍，并且可以实现超高压。另一方面，气温仍然相对较低。这些是预期存在于行星内部的典型物理条件。对这些样品的热物理和输运性质的实验研究将大大提高我们对不同类型行星形成和演化的认识。

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引用次数: 0