Developments for the In-Medium No-Core Shell Model

The in-medium no-core shell model (IM-NCSM) is a hybrid approach that aims to combine the advantages of the in-medium similarity renormalization group (IMSRG) and the no-core shell model (NCSM). The IMSRG is an established many-body method to generate effective nuclear Hamiltonians and observables in a systematic way, using continuous unitary transformations. The NCSM can exactly diagonalize Hamiltonians in a truncated many-body model-space to extract spectra, wave functions and observables of nuclei. In combination, these techniques allow the tuning of effective Hamiltonians and operators for targeted reference states and allow the convergence of observables in much smaller than conventional model-spaces, therefore extending the reach of the NCSM to heavier nuclei. In this contribution, we present new IM-NCSM developments and selected applications.