See Also:

xi (iou)



xi noun. LME.
[Greek.]
The fourteenth letter (, ) of the Greek alphabet. LME.
Particle Physics. Either of a pair of hyperons (and their antiparticles) having a mass of approximately 1320 MeV, spin of 1 / 2, hypercharge 1, isospin 1 / 2, and even parity, which on decaying usually produce a lambda particle and a pion. Freq. written . Also xi hyperon, xi particle. M20.