Some processes which are expected to lead to the growth of solid particles in the primordial solar nebula are investigated for two evolutionary phases of the nebula; one is the early phase when the nebula was contracting nearly freely, and the other is the later phase after it flattened into a gaseous disk which is rotating about the protosun.
For the free-fall phase, the collision between grains is found to be too infrequent to lead to their agglomeration for both of the two cases where the motion of grains is thermal or it shares the turbulent motion of the gas.
For the disk phase, it is found that solid particles can hardly grow to a centimeter size even in 109 years if only the collision is considered. However, they are found to sink towards the equatorial plane of the disk in about 106 years to form a high density layer where their collision is greatly accelerated. The time of this sedimentation is independent of the luminosity of the protosun.
When the density of this layer becomes greater than the Roche density, the fragmentation may occur to form the protoplanets. Finally, the effect of mass ejection from the protosun on the growth of solid particles is investigated.
Dynamical Contraction of Infinite Plane-Symmetric Gas Clouds Takashi Kusaka
Size Distribution of Grains Growing by Thermal Grain-Grain Collision Chushiro Hayashi and Yoshitsugu Nakagawa
Comments on Growth of Solid Particles by Turbulence in Collapsing Clouds Gp. Horedt
Formation of the Planets Chushiro Hayashi, Isao Adachi and Kiyoshi Nakazawa
The Gas Drag Effect on the Elliptic Motion of a Solid Body in the Primordial Solar Nebula Isao Adachi, Chushiro Hayashi and Kiyoshi Nakazawa
Statistical Behavior of Planetesimals in the Primitive Solar System Yoshitsugu Nakagawa
Instability of a Gaseous Envelope Surrounding a Planetary Core and Formation of Giant Planets Hiroshi Mizuno, Kiyoshi Nakazawa and Chushiro Hayashi
Formation of the Giant Planets Hiroshi Mizuno
Dissipation of the Primordial Terrestrial Atmosphere Due to Irradiation of the Solar EUV Minoru Sekiya, Kiyoshi Nakazawa and Chushiro Hayashi
The Gaseous Flow around a Protoplanet in the Primordial Solar Nebula Satoshi Miki
Binary Sub-Millisecond Pulsar and Rotating Core Collapse Model for SN1987A Takashi Nakamura
Origin of the Solar System Kiyoshi Nakazawa and Yoshitsugu Nakagawa
Structure of the Solar Nebula, Growth and Decay of Magnetic Fields and Effects of Magnetic and Turbulent Viscosities on the Nebula Chushiro Hayashi
Chapter 11. Cooling of the Solar Nebula Sei-ichiro Watanabe and Yoshitsugu Nakagawa
Chapter 22. Primordial Atmosphere Surrounding a Protoplanet and Formation of Jovian Planets Hiroshi Mizuno and Kiyoshi Nakazawa