arpes.analysis.tarpes.relative_change

arpes.analysis.tarpes.relative_change(data, t0=None, buffer_fs=300, *, normalize_delay=True, divide_by_spectrum=False)

Calculate relative Tr-ARPES change in a delay scan.

Subtracts the mean of the pre-t0 spectrum. Optionally, the result is divided by the original spectrum.

Parameters:

• data – Input spectrum. Should have a “delay” dimension.

• t0 – Time-zero (fs). If None, determined automatically.

• buffer_fs – Width (fs) of pre-t0 region used as equilibrium reference.

• normalize_delay – If true, normalize along “delay” dimension before processing.

• divide_by_spectrum – If true, divide subtracted spectrum by the original spectrum (like normalized_relative_change).

Returns:

Relative (and optionally normalized) change map.

Return type:

xr.DataArray