Collisional and molecular spectroscopy in an ultracold Bose-Bose mixture

The route towards a Bose-Einstein condensate (BEC) of dipolar molecules requires the ability to efficiently associate dimers of different chemical species and transfer them to the stable rovibrational ground state. Here, we report on recent spectroscopic measurements of two weakly bound molecular levels and newly observed narrow d-wave Feshbach resonances. The data are used to improve the collisional model for the Bose-Bose mixture 41 K87 Rb, one of the most promising candidates to create a molecular dipolar BEC.