R Value measurement from 3.850 to 4.590 GeV Lipeng Zhou H.M.Hu B.X.zhang 2017/11/15

outline Introduction Data sets Selection criteria Comparison with MC and Data Results on R value measurement 2017/11/15

R value measurement 𝑅= 𝜎 ℎ𝑎𝑑 0 ( 𝑒 + 𝑒 − → 𝛾 ∗ →hadrons) 𝜎 𝜇𝜇 0 ( 𝑒 + 𝑒 − → 𝛾 ∗ → 𝜇 + 𝜇 − ) = 𝑁 ℎ𝑎𝑑 − 𝑁 𝑏𝑔 𝜎 𝜇𝜇 0 𝜀 ℎ𝑎𝑑 1+𝛿 𝐿 𝑁 ℎ𝑎𝑑 observed handronic events 𝑁 𝑏𝑔 residual background events 𝜎 𝜇𝜇 0 tree level cross section of 𝑒 + 𝑒 − → 𝜇 + 𝜇 − 𝜀 ℎ𝑎𝑑 selection efficiency 1+𝛿 radiative correction factor L integrated luminosity 2017/11/15

Data sets & MC samples Data energy range : 3.850~4.590Gev 104 energy points MC version: BOSS664p01 MC sample 𝑒 + 𝑒 − → hadrons(LUNDARLW) 𝑒 + 𝑒 − → 𝑒 + 𝑒 − (babayaga)(efficiency calculation) 𝑒 + 𝑒 − → 𝜇 + 𝜇 − (babayaga) 𝑒 + 𝑒 − → τ + τ − (KKMC) 𝑒 + 𝑒 − → γγ (babayaga) 𝑒 + 𝑒 − → 𝑒 + 𝑒 − X(two photon process) 2017/11/15

Selection criteria charged track |Vr|<1.0cm neutral track |cos𝞱|<0.93 Ptrk<0.94Ebeam Veto deutron： 𝒅𝑬/𝒅𝒙(𝒎𝒆𝒂𝒔）−𝒅𝑬/𝒅𝒙(𝒑𝒓𝒐𝒕𝒐𝒏) 𝞼(𝒑𝒓𝒐𝒕𝒐𝒏) <𝟏𝟎 veto large-momentume± P>0.65 Ebeam&E/p>0.8 veto e± from gamma conversion: if M(e+e-)<0.1 & angle(e+e-)<150 neutral track E>0.1 GeV(Nch=2) 𝞱γ chg>200 T<14 ns E>0.25GeV barrel(other Nch) E>0.50 GeV endcap 2017/11/15

Selection criteria For N=3: E/p>0.8 angle of two largest energetic tracks, |𝞱1st+𝞱2nd-180 |>150,||𝞅1st-𝞅2nd|-180|>100 XratE>0.25 XratE= 𝒑𝒓𝒐𝒃𝑬 𝒑𝒓𝒐𝒃𝑬+𝒑𝒓𝒐𝒃π+𝒑𝒓𝒐𝒃𝑲+𝒑𝒓𝒐𝒃𝑷 For N=2: |𝞱1+𝞱2-180|>150 ,||𝞅1 -𝞅2|-180|>100 Number of isolated photons>=2 For N=1: 0.11<Mπ0<0.15 Evis>0.5*Ecm Balance<0.97 Balance = Σ𝒑 Σ𝑬 For all events: Eemc>0.65*Eb & |𝞱1st+𝞱2nd-180 |>100 2017/11/15

Comparison with MC and Data 2017/11/15

Comparison 2017/11/15

Comparison 2017/11/15

Comparison 2017/11/15

Comparison 2017/11/15

Comparison 2017/11/15

Comparison 2017/11/15

Results of R value measurement 2017/11/15

R-value 2017/11/15

R-value 4.310 2017/11/15

MC效率 2017/11/15

1+δ 2017/11/15

Ecm(Gev) Nhad Nbg 𝝈 𝝁𝝁 𝟎 L( 𝒑𝒃 −𝟏 ) ε 𝒇 𝒊𝒔𝒓 R 3.850 139025 13544 5.855962 7.967 0.79971 1.40597 2.392 3.890 138881 13561 5.73615 7.758 0.800615 1.36654 2.574 3.895 137247 13285 5.721433 7.567 0.798765 1.36182 2.632 3.900 139097 13318 5.706772 7.575 0.80165 1.3571 2.674 3.905 141580 13470 5.692167 7.596 0.803735 1.35239 2.726 3.910 136379 12947 5.677619 7.24 0.802655 1.34765 2.776 3.915 141482 13293 5.663126 7.454 0.80702 1.34287 2.802 3.920 129977 12172 5.648688 6.806 0.814065 1.33802 2.813 3.925 128445 11985 5.634306 6.694 0.81403 1.33308 2.845 3.930 128925 12025 5.619978 6.735 0.814185 1.32801 2.856 3.935 138596 12926 5.605705 7.161 0.815865 1.32278 2.901 3.940 140907 13018 5.591487 7.228 0.81097 1.31734 2.962 3.945 148068 13716 5.577322 7.59 0.814585 1.31164 2.970 3.950 152486 13975 5.563211 7.714 0.81512 1.30562 3.033 3.955 160167 14811 5.549154 8.124 0.81519 1.29921 3.044 2017/11/15

Ecm(Gev) Nhad Nbg 𝝈 𝝁𝝁 𝟎 L( 𝒑𝒃 −𝟏 ) ε 𝒇 𝒊𝒔𝒓 R 3.960 168872 15463 5.535149 8.489 0.813675 1.29231 3.105 3.965 155693 14254 5.521198 7.768 0.81365 1.28482 3.155 3.970 146369 13417 5.5073 7.321 0.80933 1.27661 3.192 3.975 162170 14815 5.493454 8.062 0.80908 1.26753 3.244 3.980 159260 14355 5.47966 7.851 0.81239 1.25739 3.297 3.985 162190 14684 5.465918 7.969 0.812455 1.24597 3.345 3.990 163823 14714 5.452227 8.024 0.813375 1.23303 3.398 3.995 165354 14758 5.438588 7.985 0.816445 1.21829 3.486 4.000 161666 14353 5.425 7.732 0.81419 1.20151 3.590 4.005 160021 14035 5.411463 7.537 0.817325 1.18253 3.703 4.010 153352 13395 5.397976 7.183 0.82063 1.1614 3.787 4.012 148701 12850 5.392596 6.907 0.820015 1.15243 3.860 4.014 145897 12472 5.387223 6.694 0.82272 1.14325 3.934 4.016 145378 12169 5.381859 6.544 0.821075 1.13394 4.062 4.018 157920 13011 5.376503 6.968 0.825455 1.1246 4.167 2017/11/15

Ecm(Gev) Nhad Nbg 𝝈 𝝁𝝁 𝟎 L( 𝒑𝒃 −𝟏 ) ε 𝒇 𝒊𝒔𝒓 R 4.020 155484 12546 5.371154 6.726 0.827385 1.11537 4.287 4.025 163336 12211 5.357818 6.538 0.82903 1.09391 4.757 4.030 421859 30788 5.344531 16.451 0.827315 1.07749 4.990 4.035 172675 12586 5.331294 6.706 0.83254 1.0697 5.028 4.040 165514 12312 5.318106 6.564 0.833795 1.07397 4.901 4.050 160578 12335 5.291876 6.567 0.831525 1.10962 4.623 4.055 166932 13032 5.278834 6.9277 0.827965 1.13554 4.476 4.060 151586 11964 5.26584 6.3381 0.82645 1.16102 4.360 4.065 167947 13310 5.252894 7.022 0.82351 1.18341 4.302 4.070 172410 13773 5.239995 7.2719 0.82202 1.20148 4.215 4.080 180696 14640 5.214341 7.7215 0.81583 1.2243 4.129 4.090 177377 14441 5.188874 7.6114 0.8184 1.23223 4.091 4.100 169794 13839 5.163593 7.2545 0.814235 1.22901 4.160 4.110 166268 13605 5.138497 7.146 0.818105 1.21724 4.175 4.120 177737 14650 5.113583 7.6485 0.817735 1.19874 4.254 2017/11/15

Ecm(Gev) Nhad Nbg 𝝈 𝝁𝝁 𝟎 L( 𝒑𝒃 −𝟏 ) ε 𝒇 𝒊𝒔𝒓 R 4.130 167100 13813 5.08885 7.2079 0.815595 1.17581 4.358 4.140 168948 13915 5.064296 7.268 0.819705 1.15287 4.457 4.145 179886 15008 5.052085 7.7742 0.82005 1.14364 4.476 4.150 177652 14787 5.039919 7.6627 0.820175 1.13738 4.521 4.160 183023 15315 5.015717 7.954 0.81956 1.13715 4.511 4.170 414122 34606 4.99169 18.008 0.826205 1.15402 4.428 4.180 167316 14065 4.967835 7.309 0.82882 1.18148 4.310 4.190 168646 14691 4.94415 7.56 0.829795 1.21041 4.101 4.195 166020 14553 4.932372 7.503 0.828605 1.22344 4.037 4.200 167361 14612 4.920635 7.582 0.827415 1.23502 4.007 4.203 149268 13200 4.913613 6.815 0.827635 1.24023 3.959 4.206 165491 14680 4.906606 7.638 0.82748 1.24688 3.900 4.210 164653 14740 4.897287 7.678 0.825845 1.25358 3.851 4.215 163164 14997 4.885675 7.768 0.822425 1.26071 3.765 4.220 162088 15305 4.874104 7.935 0.823765 1.26659 3.637 2017/11/15

Ecm(Gev) Nhad Nbg 𝝈 𝝁𝝁 𝟎 L( 𝒑𝒃 −𝟏 ) ε 𝒇 𝒊𝒔𝒓 R 4.225 161559 15807 4.862575 8.212 0.82232 1.27138 3.491 4.230 157119 15791 4.851086 8.193 0.81985 1.27523 3.401 4.235 155733 16012 4.839638 8.273 0.82098 1.27828 3.325 4.240 144610 15181 4.828231 7.83 0.819975 1.28064 3.260 4.243 156548 16480 4.821406 8.571 0.81877 1.28153 3.230 4.245 155356 16368 4.816863 8.487 0.819745 1.28243 3.234 4.248 155121 16543 4.810062 8.554 0.81917 1.28308 3.204 4.250 156720 16545 4.805536 8.596 0.817145 1.28373 3.235 4.255 155826 16709 4.794249 8.657 0.81646 1.28462 3.196 4.260 160208 17172 4.783002 8.88 0.817315 1.28516 3.206 4.265 154442 16669 4.771794 8.629 0.818015 1.28539 3.182 4.270 152971 16407 4.760625 8.548 0.817295 1.28536 3.195 4.275 153578 16471 4.749496 8.567 0.8187 1.2851 3.203 4.280 156148 16928 4.738405 8.723 0.815245 1.28464 3.216 4.285 153310 16742 4.727353 0.81531 1.284 3.210 2017/11/15

Ecm(Gev) Nhad Nbg 𝝈 𝝁𝝁 𝟎 L( 𝒑𝒃 −𝟏 ) ε 𝒇 𝒊𝒔𝒓 R 4.290 161353 17417 4.71634 9.01 0.81559 1.28318 3.237 4.300 151200 16390 4.694429 8.453 0.81926 1.28107 4.310 162120 16616 4.672671 8.599 0.81456 1.27833 3.478 4.320 169346 18083 4.651063 9.342 0.81719 1.27488 3.342 4.330 158892 16709 4.629605 8.657 0.81821 1.27055 3.413 4.340 161327 16841 4.608295 8.7 0.814135 1.26502 3.499 4.350 160215 16458 4.587132 8.542 0.81525 1.25771 3.578 4.360 154065 15611 4.566114 8.063 0.81777 1.24765 3.686 4.370 165604 16366 4.54524 8.498 0.817465 1.23316 3.833 4.380 162478 15682 4.524509 8.158 0.82025 1.21152 4.002 4.390 150942 14457 4.50392 7.46 0.82366 1.17914 4.183 4.395 151462 14319 4.493678 7.43 0.829305 1.15848 4.275 4.400 147485 13828 4.483471 7.178 0.83195 1.13617 4.394 4.410 131623 12193 4.463161 6.352 0.83168 1.10234 4.595 4.420 156679 14422 4.442988 7.519 0.83236 1.11663 4.582 2017/11/15

Ecm(Gev) Nhad Nbg 𝝈 𝝁𝝁 𝟎 L( 𝒑𝒃 −𝟏 ) ε 𝒇 𝒊𝒔𝒓 R 4.425 154100 14255 4.432953 7.436 0.83245 1.14166 4.464 4.430 141805 12972 4.422952 6.788 0.83339 1.17017 4.400 4.440 157022 14592 4.403052 7.634 0.827235 1.21853 4.204 4.450 156724 14728 4.383285 7.677 0.82079 1.2482 4.119 4.460 174267 16646 4.363651 8.724 0.813625 1.26425 4.025 4.480 158267 15639 4.324777 8.167 0.819725 1.27665 3.859 4.500 149615 15222 4.28642 7.997 0.811765 1.27897 3.776 4.520 160300 16527 4.248571 8.674 0.81382 1.27814 3.751 4.540 171126 17771 4.211221 9.335 0.81121 1.27631 3.768 4.550 159147 16617 4.19273 8.765 0.810635 1.27527 3.752 4.560 149378 15614 4.174361 8.259 0.80795 1.27421 3.769 4.570 149719 15854 4.156113 8.39 0.81039 1.27315 3.721 4.580 153340 16147 4.137984 8.545 0.81328 1.27211 3.750 4.590 147006 15449 4.119973 8.162 0.80617 1.27111 3.818 2017/11/15