RV-detected planets around M dwarfs: Challenges for core accretion models

Planet formation is sensitive to the conditions in protoplanetary disks, for which scaling laws as a function of stellar mass are known. We aim test whether observed population planets around low-mass stars can be explained by these trends, or if separate channels needed. address this question confronting state-of-the-art planet synthesis model with sample M dwarfs HARPS and CARMENES radial velocity (RV) surveys. To account detection biases, we performed injection retrieval experiments on actual RV data produce synthetic observations that simulated following core accretion paradigm. These simulations robustly yield previously reported high occurrence rocky generally agree their planetary function. In contrast, our cannot reproduce giant less massive than 0.5 solar masses. This potentially indicates an alternative channel least current theories. further find dependency rate short-period planets. A lack close-in earlier-type ($M_\star \gtrsim 0.4\, M_\odot$) remains unexplained dissimilar migration barriers disks different spectral subtypes. Both discrepancies attributed gaps understanding nascent dwarf systems. They underline young subtypes, importance taking differences into when studying formation.