https://spdf.gsfc.nasa.gov/pub/data/ibex/release3/lo/mass_spectrometer_data/TOF_histograms/aareadme.txt

This directory provides energy-band-specific subdirectories 
for 8-day (full IBEX orbit) files containing time-of-flightr histograms.  
For each energy band and orbit, there are three species-specific 
data files (for hydrogen, for oxygen plus carbon labelled 
"Oxygen," and for a mix of hydrogen, oxygen and carbon, labelled 
"All.")

The TOF histograms give the numbers of counts in a given
time-of-flight band, for each 0.33ns TOF range from 0-0.33ns
to 339.67-340ns, as accumulated over the full 8-day orbit,
in a given energy band, separately for each of the three
species categories specified above.

The data files are formatted as comma separated variables (CSV) 
ASCII.

The parent directory contains a documentation file created 
by the IBEX team, Maps_TOF_description.txt, that should be 
read.