Evolution of binary Model V, in which the Tayler–Spruit dynamo is not included, with orange and blue lines showing the primary and secondary stars, respectively. Panel (a) Evolution in the Hertzsprung-Russell diagram. (b,c) Evolution of ω/ω_crit and k² over the period encompassing Case B and Case BB mass transfer. (d-i) Stellar properties during Case B mass transfer and the subsequent thermal relaxation phase. Vertical cyan lines in Panels (b) to (i) mark the time when TE is re-established. Open circles in panels (b) indicate the four epochs at which the internal spin profiles are shown in Fig. , using the same colors as the corresponding lines in that figure.