Roberto Gorelli points our attention to an interested paper accepted on 28 October for publication in Monthly Notices of the Royal Astronomical Society:
What mechanisms dominate the activity of Geminid Parent (3200) Phaethon?
By LiangLiang Yu, Wing-Huen Ip and Tilman Spohn
The authors describe the physical properties of the surface crust of Phaethon and its likely dynamic evolution. The question about the presence of internal ice and the long term evolution of the gas production can explain the formation of the dust responsible for the currently known Geminid meteor shower.
The paper provides interesting reading for amateur meteor observers. The thermal model presented in section 2 requires an advanced knowledge of physics, but apart from this section 2, the paper provides interesting information in a readable way which is accessible to most amateurs.
What will the Geminids 2018 being? This paper is a good warming up to motivate the practical visual observer to monitor the activity level and particle size distribution within this meteor stream.
You can read the original paper here: https://arxiv.org/pdf/1811.00759.pdf.