  Charged hadron production in hadron-hadron collisions with longitudinal
momentum fraction Feynman-x, x_F, between 0.1 and 0.9 has not been measured
above square root s = 63 GeV at the CERN Intersecting Storage Rings. I discuss
a way to measure this at the Large Hadron Collider at square root s = 13 TeV,
which is 40,000 times higher in equivalent fixed target energy, and important
for understanding cosmic ray showers.
