Precision measurements of the scintillation pulse shape for low-energy recoils in liquid xenon

Understand

We present measurements of the scintillation pulse shape in liquid xenon for nuclear recoils (NR) and electronic recoils (ER) at electric fields of 0 to 0.5 kV/cm for energies $<$ 15 keV and $<$ 70 keV electron-equivalent, respectively.

• The average pulse shapes are well-described by an effective model with two exponential decay components, where both decay times are fit parameters.
• We find significant broadening of the pulse for ER due to delayed luminescence from the recombination process.
• In addition to the effective model, we fit a model describing the recombination luminescence for ER at zero field and obtain good agreement.