Jacob Johansen is an associated professor at Aarhus University, Denmark, with specialty in time-resolved dosimetry. He got his PhD at Aarhus University in 2012 in experimental nuclear physics. Since 2016, he has been working with research on time-resolved dosimetry. Today he is leading the in vivo dosimetry research group at Aarhus University. The focus of the group has been on clinical implementation and test of a novel dosimetry system with advanced error detection algorithms for brachytherapy. Jacob Johansen is a member of the GEC-ESTRO working group on physics and quality assurance (BRAPHYQS), where he is chair of the in vivo dosimetry work package. Currently, he is also developng new dosimetry techniques for low-energy X-rays therapy and electronic brachytherapy.