Impact of CLAS and COMPASS data on Polarized Parton Densities and Higher Twist
نویسندگان
چکیده
We have re-analyzed the world data on inclusive polarized DIS including the very precise CLAS proton and deuteron data, as well as the latest COMPASS data on the asymmetry A1, and have studied the impact of these data on polarized parton densities and higher twist effects. We demonstrate that the low Q2 CLAS data improve essentially our knowledge of higher twist corrections to the spin structure function g1, while the large Q 2 COMPASS data influence mainly the strange quark density. In our new analysis we find that a negative polarized gluon density, or one that changes sign as a function of x, cannot be ruled out from the present DIS data. PACS numbers: 13.60.Hb, 12.38.-t, 14.20.Dh
منابع مشابه
Polarized Parton Densities and Higher Twist in the Light of the Recent CLAS and COMPASS data
The impact of the recent very precise CLAS and COMPASS g1/F1 data on polarized parton densities and higher twist effects is discussed. We demonstrate that the low Q CLAS data improve essentially our knowledge of higher twist corrections to the spin structure function g1, while the large Q 2 COMPASS data influence mainly the strange quark and gluon polarizations which slightly decrease. We find ...
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