We present extractions of the nucleon nonsinglet moments utilizing new precision data on the deuteron F2 structure function at large Bjorken-x determined via the Rosenbluth separation technique at Jefferson Lab Experimental Hall C. These new data are combined with a complementary set of data on the proton previously measured in Hall C at similar kinematics and world datasets on the proton and deuteron at lower x measured at SLAC and CERN. The new Jefferson Lab data provide coverage of the upper third of the x range, crucial for precision determination of the higher moments. In contrast to previous extractions, these moments have been corrected for nuclear effects in the deuteron using a new global fit to the deuteron and proton data. The obtained experimental moments represent an order of magnitude improvement in precision over previous extractions using high x data. Moreover, recent exciting developments in lattice QCD calculations provide a first ever comparison of these new experimental results with calculations of moments carried out at the physical pion mass, as well as a new approach that first calculates the quark distributions directly before determining moments.
Bibliographical noteFunding Information:
This work was supported in part by NSF Grants No. PHY-1002644 and No. PHY-1508272 and DOE Grants No. DE-AC02-06CH11357 and No. DE-FG02-96ER40950. We thank Natural Sciences and Engineering Research Council of Canada (NSERC) for their support. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics under Contract No. DE-AC05-06OR23177. We also thank Wally Melnitchouk for useful discussions.
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