How many magnetic red giants can we detect from asymmetries in mixed modes in the Kepler sample?

Establishing whether or not stellar cores‬‭ are magnetized is critical‬ for understanding their evolution through the large impact magnetism has on‬ angular momentum transport. Asteroseismology provides a means of doing so‬‭ by analyzing the symmetry in the frequencies of rotationally split mixed-mode‬‭ multiplets in a given red giant’s power spectrum. But to use this method, each‬‭ component of the l=1 mixed mode multiplets must be visible. A mode’s‬ visibility is compromised when its amplitude is so low that it is‬‭ indistinguishable from noise, or when the frequencies of the various azimuthal‬ orders are so similar that they cannot be identified as a multiplet. Each‬‭ scenario can occur due to various stellar properties. So far, 23 magnetized red‬ giant cores have been identified in the Kepler sample by these means of‬ analysis. However, it is unknown how many stars went undetected due to a‬ lack of mode visibility. The goal of our work is to calculate the proportion of‬‭ magnetized red giants on which we can measure dipolar mixed mode‬‭ asymmetries, and thus evaluate if only identifying 23 is expected. We started‬‭ by modeling a red giant with MESA and computed its frequencies with GYRE.‬‭ Next, magsplitpy developed by Das et al. (2020) and Das et al. (2024) was‬‭ used to calculate the relative amplitudes of the three dipole split modes for a‬‭ grid of varying inclination, orientation of a dipole magnetic field, rotation rate,‬‭ and magnetic field strength. A realistic noise level was then set to establish‬‭ what combinations of these properties result in all the modes being visible.‬‭ Finally, we apply analytic and/or observational distributions of each parameter‬‭ to calculate the probability that a red giant has one of these desired‬‭ combinations of properties. This allows us to conclude how many red giants in‬‭ the‬‭ Kepler‬‭ sample should have visible split magnetic‬‭ mixed modes and thus‬‭ could be used to study core magnetism.‬