Evolution of the average core rotational period as a function of stellar radius for different assumptions of angular momentum transport in a 1.5\({{{}{{{}{\mathrm{M}}}_\odot}}}\) model initially rotating at 50\({{}{\mathrm{km}\,{{{}{\mathrm{s}}}}^{-1}}}\). We show models without angular momentum transport (green), including transport of angular momentum due to rotational instabilities (purple) and accounting for magnetic torques in radiative regions (red, Tayler-Spruit magnetic fields). The star symbols indicate the locations of \({\rm{KIC}8366239}\) and \({\rm{KIC}5006817}\) as derived using the maximum observed splitting of their mixed modes \citep{Beck:2012,Beck:2014}. Dashed lines indicate a linear fit to the different curves during the early RGB. The vertical dotted line shows the location of H-core exhaustion. The red dotted line shows the evolution of core rotational period for a model where the resulting Tayler-Spruit diffusion coefficient has been multiplied by a factor of 100. Stars in the red giant sample of \citet{Mosser:2012} with \(R<7.5{{{}{{{}{\mathrm{R}}}_{\odot}}}}\) are shown as black dots. The best fit to the core rotation of the \citet{Mosser:2012} sample is also shown as a dashed blue line. \label{period}