Ships in the ALPS

The "Solar Hidden Photon Search" is an offspring of the ALPS experiment ("Any Light Particle Search"). This "Light shining through a wall" (LSW) experiment targets “very Weakly Interacting Sub-eV Particles“ (WISPs).

Among the possible WISP candidates are axions, likely Dark Matter constituents which have been introduced to explain the smallness of CP violation in QCD, similar axion-like particles "ALPs", light spin-1 particles "Hidden Photons", and light minicharged particles. Such particles occur naturally in realistic embeddings of the standard model into string theory.

The ALPS experiment located at DESY in Hamburg exploits resonant laser power build-up in a large-scale optical cavity to boost the available power in search of WISPs with masses up to the meV scale. ALPs could be produced by interaction of laser light photons with the strong magnetic field of a dipole magnet of the HERA proton accelerator.

© 2014, Matthias Schwarz, Hamburger Sternwarte, Universität Hamburg