The recent discovery of multiple planets in the circumbinary system
TOI-1338/BEBOP-1 raises questions about how such a system formed. The formation
of the system was briefly explored in the discovery paper, but only to answer
the question do current pebble accretion models have the potential to explain
the origin of the system? We use a global model of circumbinary planet
formation that utilises N-body simulations, including prescriptions for planet
migration, gas and pebble accretion, and interactions with a circumbinary disc,
to explore the disc parameters that could have led to the formation of the
TOI-1338/BEBOP-1 system. With the disc lifetime being the main factor in
determining how planets form, we limit our parameter space to those that
determine the disc lifetime. These are: the strength of turbulence in the disc,
the initial disc mass, and the strength of the external radiation field that
launches photoevaporative winds. When comparing the simulated systems to
TOI-1338/BEBOP-1, we find that only discs with low levels of turbulence are
able to produce similar systems. The radiation environment has a large effect
on the types of planetary systems that form, whilst the initial disc mass only
has limited impact since the majority of planetary growth occurs early in the
disc lifetime. With the most TOI-1338/BEBOP-1 like systems all occupying
similar regions of parameter space, our study shows that observed circumbinary
planetary systems can potentially constrain the properties of planet forming
discs.Comment: Accepted for publication in MNRAS, 15 pages, 10 figure