A measure of the velocity of a particle relative to that of a beam of particles, approximated by a function of its angle(noun)
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Use "pseudorapidity" in a sentence
"Jets above pseudorapidity of 3.5 or so are usually poorly reconstructed, and people have forgotten why its important."
"The researchers determined the average number of charged particles emitted perpendicular to the beam direction, known as 'pseudorapidity density'."
"First proton-proton collisions at the LHC as observed with the ALICE detector: measurement of the charged particle pseudorapidity density at Ös = 900 GeV."