Open Ph.D. positions in theoretical particle physics The Collaborative Research Center “Particle Physics Phenomenology after the Higgs discovery’’ (Collaborative Research Center TRR 257), recently established by the German Research Foundation (DFG), is a joint venture of particle theorists from RWTH Aachen University, the Karlsruhe Institute of Technology (KIT), the University of Siegen and Heidelberg University. The Center invites applications for a number of Ph.D. positions. Candidates should submit an application through the following link https://academicjobsonline.org/ajo/jobs/13034. The application should include a cover letter, curriculum vitae, a short summary of research interests and copies of grades transcript. Furthermore, the applicants should arrange for at least one letter of reference, and they should indicate three projects they would like to participate in and/or three principle investigators they would like to work with. The Collaborative Research Center explicitly encourages applications from qualified women. Applicants with disabilities will be given preference if equally qualified. The applications will be considered until the positions are filled. For further information about research in theoretical particle physics at KIT, RWTH Aachen University, the University of Siegen and Heidelberg Universitysee https://www.kceta.kit.edu/, http://www.particle-theory.rwth-aachen.de/c ms/~fywf/Particle-Theory, http://www.physik.uni-siegen.de/tp1/, http://www. thphys.uni-heidelberg.de