Speaker
Description
The ALPS II experiment is an ongoing search for ultralight particles beyond the Standard Model of particle physics. The experiment utilizes an infrastructure unique in the world: a string of 24 straightened and aligned superconducting 5.3 T dipole magnets, with a bore sufficient to accommodate a 250-meter-long, high-finesse optical cavity. The combination of a long-storage-time optical resonator and a strong external magnetic field provides an opportunity to test nonlinear effects in quantum electrodynamics, namely the magnetic birefringence of the vacuum. Utilizing a novel sensing scheme, we expect to achieve sensitivity to the QED-predicted value of the macroscopic vacuum birefringence after approximately three weeks of integration time. Precise measurement of vacuum birefringence or dichroism can also be used as a test for new physics.
The facility also permits more exotic searches for both dark matter and gravitational waves using precision polarimetric techniques currently under development, as well as optical-frequency gravitational waves via the inverse Gertsenshtein effect. The infrastructure, including world-record storage-time optical cavities, is suitable for technology development in the fields of mirror coating design and metrology. In this presentation, I will detail the technical and scientific achievements of the ALPS II experimental facility and illustrate the potential of harnessing the experiment to explore further topics.