Fast Simulation of Higgs Recoil Mass

Transcription

1 Fast Simulation of Higgs Recoil Mass YANG Ying 1 2 RUAN Manqi 2 JIN Shan 2 1 Central China Normal University 2 Institute of High Energy Physics Chinese Academy of Sciences 1

2 Outline From ILD to CEPC detector TPC radius optimization Full simulation to fast simulation Summary More details & code 2

3 Reference detector: ILD ILD is perfect reference for CEPC: 1. The same beam type:e + e - 2. The similar physics goals 3

4 From ILD to CEPC detector C.M.S energy reduced from up to 1TeV to 250GeV, so we need to consider many new designs for CEPC, such as: Changed granularity Changed L* Changed VTX inner radius Changed TPC outer Radius Changed Detector Half Z Changed Yoke/Muon thickness Changed Sub detector design All these items should be optimized based on simulation, iterate with physics analysis (Fast Full Simulation) and cost estimation 4

5 ILD cost Left: the relative contribution of each sub-component to the total cost of the ILD detector. Right: scaling of the cost of the ILD detector if the transverse size is changed, split into relative cost changes for the different sub-detectors 5

6 Cost estimation: extrapolate from ILD Thick/Thin Yoke ILD Cost ~ 400 MILCU~TPC 1808mm CEPC detector ~ 270 MILCU ~ 1.6 Billion CNY ~TPC1365mm So, it is one of important tasks to study TPC radius and to find a balance between physics performance and cost. 6

7 TPC radius optimization e + e - ZHl + l - H is a gold channel to study Higgs properties, in which Higgs can be reconstructed by recoil mass of l + l -, so we select this channel to optimize TPC radius. Now, only the full simulation of ILC experiment is available for us, but it will take quite long time (~7months) to do such kind of optimization, so a fast simulation is necessary to be implemented. In the following, we will show you some details about fast simulation development and physics performance with different TPC radius. 7

8 Flow chart of fast simulation /e Single particle p(,e) Full simulation fit the momentum Mokka Generator ILC official sample Fast simulation Recoil mass Marlin 8

9 Full simulation 9

10 Generation Particle type: +,e+ Energy: 10, 20, 30, 40, 50, 60, 70, 80, 90,100GeV TPC radius: 1365, 1465, 1565, 1665, 1808 (default)mm Statistic: 50,000 particles at each point Detector base: ILD_o2_v05 Software version: ilcsoft_v01-16, Mokka 08_00_03 10

11 Fitting the momentum Fit shape: Gaussian TPC radius: 1365mm + 10GeV/100GeV Fit shape: crystal ball TPC radius: 1365mm e+ 10GeV/100GeV 11

12 Tracker performance at different TPC radius (e + / + ) Based on Full simulated particle gun events with various Energy, type and polar angle, we do the fast simulation. In fast simulation, for any observable, reconstruction value= truth value resolution 12

13 Fast simulation 13

14 Generator ILC official sample at 250GeV:.stdhep form Convert stdhep to slcio: > Marlin /besfs/groups/higgs/users/yangy/higgsmassfastsimu/ steer/ GenConv.steer dumpevent *.slcio 1(event ID) check sample information Signal:e + e - ZH + - H e + e - ZH e + e - H Background: e + e - ZZ/WW(ll or semi-l) 14

15 Event selection(r=1365mm) select one ll pair in final state. For events more than one ll candidates, the invariant mass of ll near the Z mass is the right pair. e + e - ZH + - H e + e - ZH e + e - H 15

16 Truth Vs 1808 Vs 1365 e + e - Z H + - H e + e - Z H e + e - H Width dominated by intrinsic term, thus R at 1365mm is acceptable. Right plot: electron radiation. 16

17 Recoil mass at different TPC Radius e + e - Z H + - H TPC radius = 1365mm TPC radius = 1465mm TPC radius = 1565mm TPC radius = 1665mm TPC radius = 1808mm 17

18 Recoil mass at different TPC Radius e + e - Z H e + e - H TPC radius = 1365mm TPC radius = 1465mm TPC radius = 1565mm TPC radius = 1665mm TPC radius = 1808mm 18

19 Mass spectrum with background e + e - ZH + - H Need further study to measure the mass and Xsec. 19

20 Summary Fast simulation tool for Higgs mass is mature. Can be extended to other geometry Can be applied for any beam condition. 20

21 More details 21

22 Preparation Your account Download Xmanager Open Xshell to login in 1. ssh 2. Enter the password Your working directory 1. /besfs/groups/higgs/users/your account(50g) du sh 22

23 Environment setting Copy.bash_profile to your directory 1.cp /besfs/groups/higgs/users/manqi/training/analysis/higgsmassfasts imu/trackerperformance /.bash_profile./ 2.modify line 9 source.bash_profile, then type root. You have set your environment successfully. 23

24 Generation Single particle: /e > cd /besfs/groups/higgs/users/yangy/loops/ >./obj_mu+.sh You can generate samples automatically. 24

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26 Reconstruction Full simulation: > cd /besfs/groups/higgs/users/yangy/fullpandorareco/steer/ > Marlin AHCAL.xml 26

27 Analysis cd /besfs/groups/higgs/users/yangy/anageo For the first time, remove all the files in build, then type > HFcmake > make > make install >.loadldd.sh > Marlin e+_r_1365_10gev.steer 27

28 At code level Marlin Module Content 28

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32 Thank you for your attention! Wish you have a good time in IHEP! 32

33 bakup 33

34 Linux commands kpasswd: edit your password cd: change directory 切换目录 ls: List files 列出目录下的文件 pwd: print working directory 打出当前工作目录 mkdir: Make directory 建立目录 vi: visual interface 有很多种模式 mv: move file 移动文件 rm: remove file 删除文件 cp: copy file 复制文件 ln: link files 链接文件 chmod: change mode 改变模式 ( 属性 ) You must remember all the commands! 34

35 Root & C++ Root homepage A simple sample in /besfs/groups/higgs/users/yangy/training/ 1. a root file: TrackerAna_R1365_10GeV.root 2. script for a plot of momentum: root Draw_p.cxx 35