For bcm u1: T->Draw("right_bcm_u1:right_clkcount/1024.","right_bcm_u1>230000&&right_clkcount/1024.","right_bcm_u1>230000&&right_bcm_u1<242000") TCut cut1 = "right_bcm_u1>230000 && right_bcm_u1<245000 && IBC0L02Current > 20" TCut cut2 = "right_bcm_u1>116000 && right_bcm_u1<122000" TCut cut3 = "right_bcm_u1>48000 && right_bcm_u1<50000" TCut cut4 = "right_bcm_u1>23000 && right_bcm_u1<25000 && right_clkcount/1024.< 825" TCut cut5 = "right_bcm_u1>12000 && right_bcm_u1<14000" TCut cut6 = "right_bcm_u1>4600 && right_bcm_u1<5600" TCut cut7 = "right_bcm_u1>2600 && right_bcm_u1<2700" TCut cut8 = "right_bcm_u1>1520 && right_bcm_u1<1620" TCut cut9 = "right_bcm_u1>400 && right_bcm_u1<420 && right_clkcount/1024.>1315 && right_clkcount/1024.< 1400" TCut cut10 = "right_clkcount/1024.>145" TCut cut_master = (cut1 || cut2 || cut3 || cut4 || cut5 || cut6 || cut7 || cut8 || cut9) && cut10 TCut cut_ratio = (cut1 || cut2 || cut3 || cut4 || cut5 || cut6) && cut10 T->Draw("right_bcm_u1:IBC0L02Current", cut_master) u1 linear fit results: root [17] Fitting results: (including zero) Parameters: NO. VALUE ERROR 0 1.406521e+03 4.273417e-03 1 2.358929e+03 7.709013e-05 u1 linear fit result: (nonzero) root [10] Fitting results: Parameters: NO. VALUE ERROR 0 1.300602e+03 5.556843e-03 1 2.360177e+03 8.772781e-05 Another method: check with data where beam was off: offset roughly to be 403.8 u1 pol2 Fitting results: (including zero) Parameters: NO. VALUE ERROR 0 1.468872e+03 4.878042e-03 1 2.348361e+03 4.060688e-04 2 1.042904e-01 3.934503e-06 a= 1.468872e+03, b= 2.348361e+03, c= 1.042904e-01 dela=4.878042e-03, delb= 4.060688e-04, delc= 3.934503e-06 d= -5.6139e-1, e= 1.02369, f= -2.7327e-4 deld= 6.9891e-2, dele= 5.6571e-3, delf= 5.4052e-5 BCM = a+b(0L02)+c(0L02)*(0L02); 0L02= d+e(FCup)+f(FCup)*(FCup); so, BCM= (a+bd+c*d*d) + (b*e+2*c*d*e)(FCup) + (b*f+2*c*d*f+c*e*e)(FCup)*(FCup) let A1= a+b*d+c*d*d, A2=b*e+2*c*d*e, A3=b*f+2*c*d*f+c*e*e, get: BCM=A1+A2*FCup+A3*FCup*FCup A1=1.50558486240234373e+02 A2=2.40387380292998478e+03 so, b*f= -6.4174e-01, 2c*d*f= 3.1999e-05, c*e*e = 1.0929e-01 which means A3= -5.3242e-01 delA3= delx1+delx2+delx3; delx1=b*f*sqrt((delb/b)*(delb/b)+(delf/f)*(delf/f))= 1.26933608772048512e-01; delx2=2*c*d*f*sqrt((delc/c)*(delc/c)+(deld/d)*(deld/d)+(delf/f)*(delf/f))=7.47857381571946920e-06 ; delx3=c*e*e*sqrt((delc/c)*(delc/c)+2*(dele/e)*(dele/e))=8.54135372484207548e-04; so delA3= 1.27795222718348450e-01 Fitting results: (nonzero) Parameters: NO. VALUE ERROR 0 1.365312e+03 7.132999e-03 1 2.353379e+03 4.779926e-04 2 6.401842e-02 4.424494e-06 For bcm d1 TCut cut1 = "right_bcm_d1>235000 && right_bcm_d1<245000 && IBC0L02Current > 20" TCut cut2 = "right_bcm_d1>119000 && right_bcm_d1<123000" TCut cut3 = "right_bcm_d1>48000 && right_bcm_d1<51000" TCut cut4 = "right_bcm_d1>23000 && right_bcm_d1<25000&& right_clkcount/1024.> 759 &&right_clkcount/1024.< 825" TCut cut5 = "right_bcm_d1>12000 && right_bcm_d1<14000" TCut cut6 = "right_bcm_d1>4600 && right_bcm_d1<5600" TCut cut7 = "right_bcm_d1>2400 && right_bcm_d1<2800" TCut cut8 = "right_bcm_d1>1380 && right_bcm_d1<1440" TCut cut9 = "right_bcm_d1>150 && right_bcm_d1<170 && right_clkcount/1024.>1319 && right_clkcount/1024.< 1400" TCut cut10 = "right_clkcount/1024.>142" TCut cut_master = (cut1 || cut2 || cut3 || cut4 || cut5 || cut6 || cut7 || cut8 || cut9) && cut10 TCut cut_ratio = (cut1 || cut2 || cut3 || cut4 || cut5 || cut6) && cut10 T->Draw("right_bcm_d1:IBC0L02Current", cut_master) T->Draw("right_bcm_d1:IBC0L02Current", cut_ratio) d1 linear fit results: Parameters: NO. VALUE ERROR 0 1.300209e+03 4.273417e-03 1 2.394040e+03 7.709013e-05 Parameters: (nonzero) NO. VALUE ERROR 0 1.247335e+03 5.556843e-03 1 2.394664e+03 8.772781e-05 d1 pol2 fit result: Parameters: NO. VALUE ERROR 0 1.406521e+03 4.273417e-03 1 2.358929e+03 7.709013e-05 2 -3.667413e-02 3.934503e-06 Parameters: (nonzero) NO. VALUE ERROR 0 1.166213e+03 7.132999e-03 1 2.403187e+03 4.779926e-04 2 -8.025566e-02 4.424494e-06 ---------------------------------------------------- d10 TCut cut1 = "right_bcm_d10>1100000 && right_bcm_d10<1110000 && ((right_clkcount/1024.0 > 150 && right_clkcount/1024.0<185 )||(right_clkcount/1024.0 > 245 && right_clkcount/1024.0<280 )|| (right_clkcount/1024.0 > 315 && right_clkcount/1024.0<340 )||(right_clkcount/1024.0 > 150 && right_clkcount/1024.0<185 )||(right_clkcount/1024.0 > 365 && right_clkcount/1024.0<425 ))" TCut cut2 = "right_bcm_d10>1000000 && right_bcm_d10<1020000 && right_clkcount/1024.0 > 485 && right_clkcount/1024.0<545 " TCut cut3 = "right_bcm_d10>480000 && right_bcm_d10<490000 && right_clkcount/1024.0 > 645 && right_clkcount/1024.0<720 " TCut cut4 = "right_bcm_d10>220000 && right_bcm_d10<240000 && right_clkcount/1024.0 > 760 && right_clkcount/1024.0<820 " TCut cut5 = "right_bcm_d10>120000 && right_bcm_d10<130000 && right_clkcount/1024.0 > 895 && right_clkcount/1024.0<945 " TCut cut6 = "right_bcm_d10>45000 && right_bcm_d10<50000 && ((right_clkcount/1024.0 > 980 && right_clkcount/1024.0<1025)||(right_clkcount/1024.0 > 1055 && right_clkcount/1024.0<1110) )" TCut cut_master = cut1 || cut2 || cut3 || cut4 || cut5 || cut6 TCut cut_linear = cut2 || cut3 || cut4 || cut5 || cut6 T->Draw("right_bcm_d10:IBC0L02Current", cut_master) T->Draw("right_bcm_d10:IBC0L02Current", cut_ratio) p01 fit: Parameters: NO. VALUE ERROR 0 3.587101e+04 6.622983e-03 1 1.996563e+04 2.840143e-04 p02 fit: NO. VALUE ERROR 0 8.704371e+03 8.913226e-03 1 2.504542e+04 1.150972e-03 2 -9.835996e+01 2.159712e-05 p02 fit: including 100uA Parameters: NO. VALUE ERROR 0 4.463970e+03 7.279708e-03 1 2.815776e+04 5.170456e-04 2 -1.716813e+02 4.815092e-06