简介:Weintroducethepolarizedvalondistributionstodescribethespindependenceofpartondistributions.Thepolarizedvalondistributionsintheprotonandpolarizedpartondistributionsinsidethevaloncanhelptoobtainpolarizedpartondistributioninaproton.Inordertobeabletoobtainthespincontributionofseaquarks,weneedtoimprovethevalonmodelWeemploytheBernsteinpolynomialaveragestoobtaintheunknownparameterswhichexistinourcalculations.Ourresultsforthepolarizedprotonstructurefunction,xg1p,areingoodagreementwiththeexperimentaldataforsomevaluesofQ2.
简介:LargescaleQCDMonteCarlocalculationshavetypicallybeenperformedoneithercommercialsupercomputersorspeciallybuiltmassivelyparallelcomputerssuchasFermilab'sACPMAPS.Commodityclustersequippedwithhighperformancenetworkingequipmentpresentanattractivealternative,achievingsuperiorperformancetopriceratiosandofferingclearupgradepaths.WedescribetheconstructionandresultstodateofFermilab'sprototypeproductioncluster,whichconsistsof80dualPentiumⅢsystemsinterconnectedwithMyrinetnetworkinghardware.Wedescribesoftwaretoolsandtechniqueswehavedevelopedforoperatingsysteminstallationandadministration.WediscusssoftwareoptimizationsusingthePentium'sbuilt-inparallelcomputationfacilities(SSE),Finally,wepresentshortandlongtermplansfortheconstructionoflargerfacilities.