Hadroproduction of Charmonium at Large x
نویسنده
چکیده
We present a higher-twist production mechanism for η c and χ J charmonium at large momentum fraction x F in pion-nucleon collisions. The higher-twist contribution is essentially independent of x F and therefore becomes dominant at large x F , where the leading-twist contribution falls off as (1 − x F) 3. We show that the higher-twist mechanism produces longitudinally polarized χ 1 and χ 2. For the χ 2 , this is clearly different from the leading-twist prediction of transverse polarization. For the χ 1 , the polarization of the leading-and higher-twist contributions is qualitatively similar.
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