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< P(e,i) > is defined by < P(e,i) >=∫(3/2)|b|(1/(2π)^2)p_col(e, i, b, τ, ω)dτdωdb, ・・・・・・(10) where p_col(e, i, b, τ, ω) is collisional probability, that is, it is unity if the planetesimal collides with the protoplanet, and zero otherwise. よろしくお願いします。

We should note that the scaled value of r_p is independent of the protoplanet mass. Supposing that ρ=3gcm^-3, we have r_p=0.005 and 0.001 at the Earth and Jupiter orbits, respectively. At the Neptune orbit, ρis certainly smaller than that at the Earth orbit; if we assume ρ=1gcm^-3, r_p is 0.0002 at this orbit.

In order to obtain the total collisional rate <Γ(e_1, i_1)>, we have to find <P(e,i)> numerically by computing orbits of relative motion between the protoplanet and the planetesimal. Since <P(e,i)> should be provided for wide ranges of e and i with a sufficient accuracy, we are obliged to compute a very large number of orbits. In practice, it is an important problem to find an efficient method for numerical computation. In the second paper (Nakazawa et al., 1989b, referred to as Paper II), we have studied the validity of the two-body approximation and found that within the sphere of the two-body approximation (hereafter referred to as the two-body sphere), the relative motion can be well described by a solution to the two-body problem: the sphere radius has been found to be r_cr=0.03(a_0*/1AU)^(-1/4)(ε/0.01)^(1/2). ・・・・・(13) Within the sphere, the nearest distance can be predicted with an accuracy εby the well-known formula of the two-body encounter. We can expect the above result to be useful to reduce computation time for obtaining <P(e,i)> numerically. よろしくお願いします。

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DVD Shrinkですが、２台ある外付けHDDにはISOに圧縮できますが、 もう１台（最近購入）では、エラーが出ます・・・。 「エラーにより続行することが出来ません。ファイルISOFileのシークに失敗しました」 また、上記の外付けではなく、デスクトップに保存はOKです。 なぜ、１台の外付けHDDには、ISOで書き込めないのでしょうか・・・。 よろしくお願いします。 ●Windows　7 容量はかなり余ってます。 書き込みできない、外付けHDDには初めて書き込みます。