$\Delta$ Isobar Degrees of Freedom in the $^3$He Transverse (e,e') Response Function

The $^3$He transverse electron scattering response function $R_T(q,\omega)$ is calculated in the quasi-elastic peak region and beyond for momentum transfers $q \ge$ 500 MeV/c. In addition to $\Delta$-isobar currents ($\Delta$-IC) we include meson exchange currents and relativistic corrections to one-body currents. The calculation is performed using the AV18-NN potential and the UrbanaIX three-nucleon force. The $\Delta$-IC are calculated in impulse approximation using the Lorentz integral transform (LIT) method (details are given in Ref. [1] and references therein). In addition to results for $q$=500, 600, and 700 MeV/c we plan to present results at even higher $q$. Use of the Active Nucleon Breit frame together with the two-fragment kinematical model results in excellent agreement with experiment in the quasi-elastic peak region. In addition our results suggest the importance of $\Delta$-IC for three-body break-up reactions in the dip region. \\[4pt] [1] L. Yuan, V.D. Efros, W. Leidemann, G. Orlandini, and E.L. Tomusiak, Phys. Rev. {\bf C72}, 011002(R) (2005)