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the inclusive cross section of any physics process is determined by born - cross section ( @xmath12 ) and the parton distribution functions ( pdfs ) .
therefore , the measurement of the inclusive cross section tests calculations based on the higher order perturbative quantum chromodynamics ( qcd ) and also pdfs .
especially , w and z boson processes shown in figure [ fig : wz ] are well understood and unique signature with high rate , which give a useful information of qcd and pdfs .
moreover , these processes are a good tool to calibrate the detector in the early stage and the total cross section of these processes can be used as the luminosity candles at lhc .
w or z process mediates for many complex final states like top or new physics , so the measurement of w and z production process paves the way for understanding top or new physics processes .    in the w production mechanism , it is polarized due to the parity violation at production and it gives a strong asymmetry in the lepton decay .
this asymmetry measurement constrains for the ratio of u and d quark , particulary on the sea quark contribution at lhc .
therefore , the asymmetry measurement of w boson production is important input of the global pdfs fit .    here
, we measure the inclusive cross section and its ratio of w and z production decaying to electrons or muons with the data sample taken from 2010 lhc operation period ( 36 @xmath1 ) .
a detailed description of the cms detector can be found in ref .
the cms detector is a superconducting solenoid , of 13 m in length and 6 m in diameter , which provides an axial magnetic field of 3.8 t. the innermost layer is a silicon tracker which covers the pseudorapidity , @xmath13 ( @xmath14 where @xmath15 is the polar angle of the trajectory of the particle with respect to the beam direction .
outside of the silicon tracker , the scintillating crystal electromagnetic calorimeter ( ecal ) and the brass / scintillator hadron calorimeter ( hcal ) follow .
the ecal provide coverage of @xmath16 in the barrel region and @xmath17 in the endcap region .
the muon system is made of three technologies , drift tubes , cathode stript chambers , and resistive plate chambers .
the muon detector covers @xmath18 region and has about 2 @xmath19 transverse momentum resolution in the relevant muon @xmath20 range with the silicon track matching .
the data sample consists of 36 @xmath1 collected by cms detector at lhc during 2010 .
the analysis is performed for the electron and muon channel for w / z production .
the events from the high @xmath21 electron or the single high @xmath20 muon trigger is used to select the sample . in the muon channel ,
the muon is selected to have @xmath22 gev for w boson and @xmath23 gev for z boson in @xmath24 .
the good track quality selection is required to find a good muon and the impact parameter cut , @xmath25 mm , is also required to reduce the cosmic muon background .
the electron is required to have @xmath26 gev for w and z boson in a good detector fiducial region , @xmath27 and @xmath28 .
the high @xmath21 electron cluster is matched to a high @xmath20 track and also required to pass the electron identification ( i d ) variables like a shower shape and the conversion reject variables .
both electron and muon are required to be the isolated object .
since the w production has large drell - yan background contamination , the drell - yan background is reduced by rejecting the event with the second isolated lepton with loose selection .
the acceptance is calculated using  monte carlo ( mc ) @xcite generator interfaced with  parton showering .
the  generator is combined with a  @xcite simulation of the cms detector .
the acceptance is the event fraction of the event with kinematic selection ( @xmath29 gev for w selection , and @xmath30 gev for z selection in the detector fiducial region ) to the generated events .
the acceptance for the z boson measurement is restricted by the z mass range , @xmath31 gev .
the total acceptance is 50 @xmath19 for w boson and 40 @xmath19 level for z boson .
table [ tab : acp ] summarizes the acceptance for each channel .
.the acceptance ( @xmath32 ) of w or z boson production . [ cols="<,^,^",options="header " , ]     [ tab : sigma_sum ]     confidence level.,title="fig:",width=302 ]   confidence level.,title="fig:",width=302 ]   confidence level.,title="fig:",width=302 ]   confidence level.,title="fig:",width=302 ]    .,width=377 ]
in w production , it is hard to measure the asymmetry of w production directly because the momentum of @xmath33 in the longitudinal direction is unknown .
therefore , the asymmetry is measured using the final state lepton , which is the lepton charge asymmetry . the lepton charge asymmetry of w production ( @xmath34 )
is defined as : @xmath35 where @xmath36 is the pseudorapidity of the lepton in the final state .
the lepton charge asymmetry has a strong @xmath36 dependence , so it is important to understand @xmath36 dependence of efficiencies and background . in the measurement ,
the efficiencies ( reconstruction , i d , and trigger ) are estimated as a function of muon @xmath20 and @xmath36 .
the background is also estimated in @xmath36 using the shape fitting method ( @xmath37  fit for the electron channel and the isolation energy fitting for the muon channel ) from the data directly .
for the electroweak background , we use the simulation samples .
all other methods of the measurement are same as used for the inclusive cross section measurement .
the lepton charge asymmetry has @xmath20 dependence , so it is measured in two muon @xmath20 bins , @xmath38 and @xmath39 gev .
the asymmetry is measured in the electron and muon channel , respectively , and shows a good agreement between these two channels .
figure [ fig : asym ] shows the lepton charge asymmetry in @xmath36 and @xmath20 compared to the theory predictions ,  @xcite with cteq10w @xcite and nlo mstw2008 @xcite pdfs .
the precision of the measurement is less than 1.1 @xmath19 for the statistical uncertainty and 1.5 @xmath19 for the total uncertainty in all @xmath36 bins .
this measurement is new input to pdf global fit which constrains to the u and d quark ratio .
we measure the inclusive cross section of w and z boson production and its ratio using 36 @xmath1 data at cms .
the inclusive cross section measurements show a good agreement with nnlo qcd theory prediction .
the lepton charge asymmetry of w production is also measured and compared with various pdfs set , cteq10w and nlo mstw2008 .
more analysis detail is in ref .
@xcite for the inclusive cross section measurement and ref .
@xcite for the lepton charge asymmetry measurement .
we thank the technical and administrative staff at cern and other cms institutes , and acknowledge support from : fmsr ( austria ) ; fnrs and fwo ( belgium ) ; cnpq , capes , faperj , and fapesp ( brazil ) ; mes ( bulgaria ) ; cern ; cas , most , and nsfc ( china ) ; colciencias ( colombia ) ; mses ( croatia ) ; rpf ( cyprus ) ; academy of sciences and nicpb ( estonia ) ; academy of finland , me , and hip ( finland ) ; cea and cnrs / in2p3 ( france ) ; bmbf , dfg , and hgf ( germany ) ; gsrt ( greece ) ; otka and nkth ( hungary ) ; dae and dst ( india ) ; ipm ( iran ) ; sfi ( ireland ) ; infn ( italy ) ; nrf and wcu ( korea ) ; las ( lithuania ) ; cinvestav , conacyt , sep , and uaslp - fai ( mexico ) ; paec ( pakistan ) ; scsr ( poland ) ; fct ( portugal ) ; jinr ( armenia , belarus , georgia , ukraine , uzbekistan ) ; mst and mae ( russia ) ; mstd ( serbia ) ; micinn and cpan ( spain ) ; swiss funding agencies ( switzerland ) ; nsc ( taipei ) ; ubitak and taek ( turkey ) ; stfc ( united kingdom ) ; doe and nsf ( usa ) .
cms collaboration , `` measurement of the lepton charge asymmetry in inclusive w production in pp collisions at @xmath46 = 7 tev '' , cms pas * ewk-2010 - 006 * ( 2010 ) , @xmath41 * 1104 * ( 2011 ) 050 , arxiv:1103.3470 , doi:10.1007/jhep04(2011)050 .
we report the measurement of the rates and asymmetries of inclusive and differential production of w and z vector bosons in pp collisions at @xmath0 tev . 
 the data consists of 36 @xmath1 collected in the compact muon solenoid ( cms ) detector at the large hadron collider ( lhc ) . 
 the measured inclusive cross sections are @xmath2(stat.)@xmath3 ( syst.)@xmath4(th.)@xmath5(lumi . ) 
 nb and @xmath6(stat.)@xmath7 ( syst.)@xmath8(th.)@xmath9(lumi . ) 
 nb . 
 the measured inclusive cross sections and also its ratio of w to z or @xmath10 to @xmath11 agree with nnlo qcd cross section calculations and current parton distribution functions ( pdfs ) . 
 the differential production asymmetry of w boson as a function of the lepton pseudorapidity in the final state is also measured and compared with various pdfs .