Photon-electron coincidence experiments at synchrotron radiation facilities with arbitrary bunch modes

Area of Science:

• Atomic and Molecular Physics
• Synchrotron Radiation Science
• Quantum Optics

Background:

• Electron-photon coincidence detection is crucial for studying atomic and molecular processes.
• Adapting this technique to multibunch modes at synchrotron sources presents challenges due to continuous excitation.

Purpose of the Study:

• To adapt electron-photon coincidence detection for the multibunch hybrid mode at BESSY II.
• To enable high-resolution coincidence measurements in quasi-continuous excitation patterns.

Main Methods:

• Utilized single-event-based data acquisition and relative detection times.
• Modeled accidental coincidences using non-coincident electron and photon spectra.
• Applied the adapted scheme to study CO2 photoionization and subsequent photon emission.

Main Results:

• Successfully validated the method by reproducing prior single-bunch results.
• Obtained radiative lifetime and electron binding energy for CO2 ionization in good agreement with literature.
• Demonstrated the method's effectiveness in multibunch hybrid mode.

Conclusions:

• The adapted coincidence detection scheme is effective for multibunch synchrotron operation.
• This technique enhances the versatility of coincidence measurements at various light sources.
• No additional experimental adjustments are needed for broader applicability.