粒子軌道の最終段階:散乱と衝突

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  • 散乱の場合、惑星の近くを通過した後、粒子の軌道は再び惑星から遠いケプラー軌道に定着します。
  • 最終的な軌道要素(b_f〜、e_f〜、ε_f、δ_f)は、もちろん、惑星との重力相互作用により、初期のものとは異なります。
  • 一方、粒子と惑星の中心との距離が惑星の半径r_pよりも小さくなると、粒子の惑星との衝突を考慮します。
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この文章の和訳をお願いします。

  We have two kinds of the final stage of the particle orbit: One is the scattering case and another is the collisional case. For the scattering case, after the passage near the planet a particle orbit settles again to the Keplerian at the region far from the planet. The final orbital elements (b_f~, e_f~, ε_f, δ_f), of course, are different from the initial owing to the gravitational interaction with the planet. On the other hand, we regard the case as the collision of the particle with the planet when the distance between the particle and the center of the planet becomes smaller than the planetary radius, r_p, which is given in the units adopted here by       r_p=R_p/R=(3M/4πρ)^(1/3)/R,        =4.57×(10^-3)h/(R/1AU),         (2・12) where R_p and R are the radius of the planet in ordinary units and the distance between the planet and the Sun, respectively. どうかよろしくお願いします。

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  • ddeana
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回答No.1

粒子軌道には2種類の最終段階がある、すなわち拡散する場合と衝突する場合である。粒子拡散では、惑星の近くを通過後、粒子軌道は惑星から離れた領域で再びケプラーの法則に落ち着く。勿論最終的な軌道要素(b_f~, e_f~, ε_f, δ_f)は、惑星との重力相互作用のせいで初期とは違っている。一方我々は、粒子と惑星の中心の間の距離がこの実験で用いた単位系で与えられた惑星の半径 r_p、よりも小さくなった時の、惑星と粒子が衝突する場合に注目している。    r_p=R_p/R=(3M/4πρ)^(1/3)/R, =4.57×(10^-3)h/(R/1AU),  (2・12) 上記数式において、R_p と R はそれぞれ、通常単位での惑星の半径と、惑星と太陽間の距離とする。

stargazer1231
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