Bounds on Heavy Axions with an X-Ray Free Electron Laser

Area of Science:

• Particle Physics
• Astroparticle Physics
• X-ray Science

Background:

• Axionlike particles are hypothetical elementary particles that could explain dark matter.
• The Primakoff effect describes the conversion of photons to axions and vice versa in strong electromagnetic fields.
• Previous experiments have searched for axionlike particles using synchrotrons, but with limited sensitivity.

Purpose of the Study:

• To establish new exclusion bounds on the mass of axionlike particles.
• To leverage the high-brightness X-ray source at the European X-Ray Free Electron Laser (EuXFEL) for enhanced sensitivity.
• To probe the mass range of 10^{-3} eV to 10^{4} eV for axionlike particles.

Main Methods:

• Utilizing the Primakoff effect for photon-to-axion conversion.
• Employing a strong external electric field to facilitate particle interactions.
• Detecting axions by observing their conversion back to photons after passing through an opaque wall.
• Conducting the experiment at the European X-Ray Free Electron Laser (EuXFEL) facility.

Main Results:

• New exclusion bounds have been established for axionlike particles within the specified mass range.
• The experiment demonstrates improved sensitivity compared to previous searches performed at third-generation synchrotrons.
• The higher brightness of X-rays at EuXFEL was crucial for achieving this enhanced sensitivity.

Conclusions:

• The study successfully constrained the parameter space for axionlike particles.
• The results highlight the potential of next-generation light sources like EuXFEL for fundamental physics searches.
• Further investigations with improved sensitivity could potentially detect or further constrain the existence of axionlike particles.