Kedron Silsbee, University of Texas at El Paso
When
Abstract: Planets form as the result of dust agglomeration in a disk around a young star. Planet formation in tight binary systems presents a number of challenges: the disks are typically less massive and shorter lived, and dynamical perturbations from the companion star excite eccentricity in the planetesimal orbits, leading to potentially destructive collisions and rapid inspiral. We constructed an analytic model of the collision velocities and use this to run numerical simulations of the coagulation process. We find that the severity of the problem depends strongly on details of the disk structure, but under favorable conditions growth to planetary size via mutual collisions is possible starting from few-kilometer planetesimals. In the second part of the talk, I will discuss calculation of the radial drift of planetesimals orbiting in an eccentric disk. I show that, (unlike in an axisymmetric disk), even in the absence of a pressure maximum, radial drift can be both towards, and away from the central star. This results in pile-up of planetesimals at particular locations in the disk, thus potentially accelerating the planet formation process.
Bio: I am an assistant professor in the Physics Department at the University of Texas at El Paso. Currently, my work focuses on understanding physical processes associated with star formation. I am currently particularly interested in orbital dynamics, planet formation around binary stars, and cosmic ray propagation. In the past, I have worked also on the formation of our Oort Cloud, black hole mergers, and anomalous microwave emission. I do a mixture of analytic work and numerical simulations. |