Prof. Dr. rer. nat Yudi Rosandi, S.Si., M.Si

Calon Promotor Padjadjaran Excellence Fastrack Scholarship Tahun 2021

Nama Lengkap : Prof. Dr. rer. nat Yudi Rosandi, S.Si., M.Si

E-mail: rosandi@geophys.unpad.ac.id

Bidang Keahlian : Geofisika

Scopus Author ID : 12781959300

Prodi S2 Calon Mahasiswa: Fisika/MIPA

Prodi S3 Calon Mahasiswa: Kimia/MIPA

Judul Penelitian yang Ditawarkan:
Analisis komputasi terhadap koagulasi debu kosmik silika: Kajian geofisika dan geokimia proses pembentukan protoplanet

Computational analysis on silicate cosmic dust coagulation: Geophysical and Geochemical study on protoplanet formation processes

Abstract:
Cosmic dust coagulation is an important process in the early stage of protoplanet formation. The collisions of such dust continuously occur in a protoplanetary disk, the birthplace of a young solar system. Albeit a common mechanism, the process is far from simple. The molecular configuration of dust particles plays a decisive role in the formation of larger objects, from nanometer size to micrometer, and hence coagulates to a macroscopically large object. In the light of collision physics, the range of energy can be identified as the colagulating energy, where two objects stick together after collision and the non-coagulating ones where the objects rebound each other, even fragmented after the collision. In the atomic view, the event is driven by the interaction between the constituted atoms, beside the kinetic energy of the dust particles. Since the collision of dust particles is hard to be observed directly, a computational model may shed light on the detailed mechanism. Study on the protoplanet formation falls into several categories, relating to the size scale under consideration. In the macroscopic point of view, one can take elasticity theory as the base of its analysis. At the microscopic level, the interaction between the building blocks of a planetary rock determines the process. One may choose the granular mechanics as tools to get insights into the accretion mechanism. At a smaller scale, such as atomistic view of the collision phenomena, the atomic and molecular interaction plays an important role in coagulation mechanism. All of these methods can be corroborated in order to obtain a complete view of the multiscale mechanism of planet formation, hence the history of planetary objects can be well understood. In this proposed research we apply the molecular dynamics method to simulate the coagulation of silica dust particles induced by energetic collision. Silica clusters are considered to represent the main component that builds up the rocky protoplanetary object. Due to the limitation of computation size, the clusters are chosen of several hundreds of nanometers, containing about several millions of atoms (Si and O).