Any Light Particle Searches with ALPS II: first science results
Authors
Daniel C. Brotherton
Sandy Croatto
Jacob Egge
Aldo Ejlli
Henry Frädrich
Joe Gleason
Hartmut Grote
Ayman Hallal
Michael T. Hartman
Harald Hollis
Katharina-Sophie Isleif
Friederike Januschek
Kanioar Karan
Sven Karstensen
Todd Kozlowski
Axel Lindner
Manuel Meyer
Guido Müller
Gulden Othman
Jan H. Põld
David Reuther
Andreas Ringwald
Elmeri Rivasto
José Alejandro Rubiera Gimeno
Jörn Schaffran
Uwe Schneekloth
Christina Schwemmbauer
Aaron D. Spector
David B. Tanner
Dieter Trines
Li-Wei Wei
Benno Willke
Rachel Wolf
Abstract
The light-shining-through-a-wall experiment ALPS II at DESY in Hamburg searched for axions and similar lightweight particles in its first science campaign from February to May 2024. No evidence for the existence of such particles was found. For pseudoscalar bosons like the axion, with masses below about 0.1 meV, we achieved a limit for the di-photon coupling strength of 1.5e-9 1/GeV at a 95% confidence level. This is more than a factor of 20 improvement compared to all previous similar experiments. We also provide limits on photon interactions for scalar, vector and tensor bosons. An achievement of this first science campaign is the demonstration of stable operation and robust calibration of the complex experiment. Currently, the optical system of ALPS II is being upgraded aiming for another two orders of magnitude sensitivity increase.
