The initial structure of chondrule dust rims II: Charged grains
The initial structure of chondrule dust rims II: Charged grains
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球粒尘埃边缘的初始结构II：带电颗粒
DOI：
10.1016/j.icarus.2020.114053
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发表时间：
2021
期刊：
影响因子：
3.2
通讯作者：
Hyde, T.W.
中科院分区：
文献类型：
--
作者：
Xiang, C.;Carballido, A.;Matthews, L.S.;Hyde, T.W.
为了刻画球粒周围细粒尘圈的早期生长过程，我们通过在球粒表面直接吸附不同大小的单体，模拟了细粒尘圈的生长过程。在太阳星云(SN)的辐射等离子体环境中，尘埃不同程度地带电，由此产生的静电力改变了碰撞尘埃颗粒的轨迹，影响了尘埃边缘的结构和边缘形成的时间尺度。我们将具有不同湍流强度和等离子体条件的原行星盘(PPD)中的FGRS的增长与以前假设中性尘埃颗粒的模型(向，C.，Carballido，A.，Hanna，RD，Matthews，LS，Hyde，TW，2019)进行了比较。我们使用蒙特卡罗方法和N-Body程序的组合来模拟半径为0.5-10μm的尘埃单体与半径在500-1000μm之间的球粒的碰撞：使用蒙特卡罗算法随机选择将与球粒碰撞的尘埃粒子，并确定碰撞之间的时间间隔；在Close Approach中，使用N体算法Aggregate Builder(AB)来模拟详细的碰撞过程，以确定碰撞结果，以及对球粒规则边缘的任何重构。为了计算方便，我们将尘埃单体的吸积限制在球粒表面的一小块区域内。这些碰撞是由布朗运动驱动的，并与原行星盘中的湍流气体运动相耦合。模拟了尘圈的电荷分布，计算了尘埃颗粒的运动轨迹，分析了尘圈的形态。在弱湍流区域，带电粒子之间相对速度的降低导致小颗粒被球粒所排斥，导致尘埃边缘生长得更慢，并由更大的单体组成，这导致了更多的多孔结构。在高度湍动的区域，电荷的存在主要通过使尘埃颗粒偏离边缘末端并减少高速碰撞引起的重整量来影响边缘的孔隙度。
In order to characterize the early growth of fine-grained dust rims (FGRs) that commonly surround chondrules, we simulate the growth of FGRs through direct accretion of monomers of various sizes onto the chondrule surfaces. Dust becomes charged to varying degrees in the radiative plasma environment of the solar nebula (SN), and the resulting electrostatic force alters the trajectories of colliding dust grains, influencing the structure of the dust rim as well as the time scale of rim formation. We compare the growth of FGRs in protoplanetary disks (PPD) with different turbulence strengths and plasma conditions to previous models which assumed neutral dust grains (Xiang, C., Carballido, A., Hanna, RD, Matthews, LS, Hyde, TW, 2019). We use a combination of a Monte Carlo method and an N-body code to simulate the collision of dust monomers of radii 0.5–10 μ m with chondrules whose radii are between 500 and 1000 μ m: a Monte Carlo algorithm is used to randomly select dust particles that will collide with the chondrule as well as determine the elapsed time interval between collisions; at close approach, the detailed collision process is modeled using an N-body algorithm, Aggregate Builder (AB), to determine the collision outcome, as well as any restructuring of the chondrule rim. For computational expediency, we limit accretion of dust monomers to a small patch of the chondrule surface. The collisions are driven by Brownian motion and coupling to turbulent gas motion in the protoplanetary disk. The charge distribution of the dust rim is modeled, used to calculate the trajectories of dust grains, and then analyze the resulting morphology of the dust rim. In a weakly turbulent region, the decreased relative velocity between charged particles causes small grains to be repelled from the chondrule, causing dust rims to grow more slowly and be composed of larger monomers, which results in a more porous structure. In a highly turbulent region, the presence of charge mainly affects the porosity of the rim by causing dust particles to deviate from the extremities of the rim and reducing the amount of restructuring caused by high-velocity collisions.
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影响因子：
3.2
作者：
C. Xiang;A. Carballido;R. Hanna;L. Matthews;T. Hyde
通讯作者：
T. Hyde
CM 球粒陨石中球粒和包裹体周围深色地幔的非星云起源
影响因子：
5
作者：
J. Trigo‐Rodríguez;A. Rubin;J. Wasson
通讯作者：
J. Wasson
太阳星云中球粒和尘埃的共同吸积
DOI：
10.1086/587836
发表时间：
2008
期刊：
The Astrophysical Journal
影响因子：
--
作者：
C. Ormel;J. N. Cuzzi;A. Tielens
通讯作者：
A. Tielens
影响因子：
3.2
作者：
J. Cuzzi
通讯作者：
J. Cuzzi
影响因子：
8.6
作者：
Blum, J;Schräpler, R
通讯作者：
Schräpler, R