Polarization ofΛ'sandΛ¯'sinpp

Abstract

We have measured the polarization of A's in inclusive pp and K~p reactions and of A's in pp interactions at a beam momentum of 176 GtV/c. Data were taken in the beam-fragmentation region with hyperon transverse momenta from 0.2 to 1.5 GeV/c. The ^-produced A's have the same magnitude and sign of polarization as the ^produced A's, whereas the A's from K~p interactions are more highly polarized and in the opposite direction.

Hyperon polarization in different inclusive production processes in unpolarized high energy hadron-hadron collisions

“…We see that clearly as x F increases from 0 to 1, the obtained P Λ (x F |s) starts from 0 and increases to about 40% at x F → 1. These qualitative features are in good agreement with the data [57,58,59,60,61].…”

Transverse Λ0 polarization in inclusive quasi-real photoproduction: Quark scattering model

“…As the preliminary HERMES data [9] turned out to be qualitatively similar with those of K − p [10], we assumed that the underlying polarization mechanisms of both the ep and K − p reactions could be similar as well. Thus we supposed the Λ 0 polarization to originate mostly in scattering of quarks coming from the positron projectile.…”

Lambda production in electron-positron annihilation at 29 GeV

“…(31) 1%1 P(p-+A) (32) + p(p-+X)(31) from the quark state and the anti-baryons from the anti-quark state that exhibit polarization. Another way to say this is that the polarization of the baryon is a result of the hadronization process and is a function of the direction of the color field.…”