You can get rid of the gas giant in your analysis by excluding everything further out than 0.2 AU. The distribution then separates more clearly into to peaks with a gap in between. But that is something I can not get in a minute or two in the online plotting tool.
Also you should be aware that astronomy and astrophysics has quite different conventions for naming things than say condensed matter. Part of the reason is that historically they were a separate science from physics. Part of the reason is that most of the knowledge is gained from (passive) observations, not actively controlled experiments.
Extra fun example: astronomy, especially radio astronomy definies left and right handed circular polarization exactly the opposite way to how optics does it...
However, gap generally reserved for lower valleys ie band gap etc. So, while shorter the term is simply misleading.