Hannes-Sebastian Zechlin Hamburg

New Constraints on Mixing Parameters of Hidden Photons using Very High Energy (VHE) Gamma-Rays from the Crab Nebula (pdf)

Extensions of the standard model often predict a new U(1) gauge symmetry in a hidden sector. The corresponding gauge boson (hidden photon) interacts with the normal photon via gauge kinetic mixing, leading to photon - hidden photon oscillations. Therefore one expects photon disappearance as a function of the mixing angle, loosely constrained from theory, and the mass of the hidden photon. Several experiments have been carried out or are planned to provide constraints on the mass-mixing plane. In this talk I present new constraints, using VHE gamma-rays detected from the Crab Nebula, whose broad-band spectral characteristics are well understood. The VHE gamma-ray observations offer the possibility to provide constraints in a broad mass range at a unexplored energy and distance scale. We use existing data taken with several IACTs. We discuss our results in context of existing constraints and consider the possibilities of using astrophysical data to search for hidden photons.