Systematic Sources
MC Samples Needed
Calculating Algorithm

Residual JES

$ vary jet energy scale for each of the 6 levels. use the 'jetsystcode' when templating, 'jes' varies the overall jet energy scale while 'jetsystcode' varies each individual level

Signal templates

  • ttop25_+/-1_0.0.root
  • ttop25_+/-4_0.0.root
  • ttop25_+/-5_0.0.root
  • ttop25_+/-6_0.0.root
  • ttop25_+/-7_0.0.root
  • ttop25_+/-8_0.0.root

Background templates

  • since bkgd is obtained from data samples, no need to vary bkgd jetsystcode


  • Use This Code to write out template scripts(see


  • Use this code to estimate JES syst templates (see /cdf/s13/tangjian/Analysis/summer2010/METJ_KDE/myKDErelease/TMTCode/kdecode/


  • In code "" set jcorrConstraint 0
Error of Error:
Nominal RMS/sqrt(3000)

Status: Done PE!


    Diffreence between:
  • ttop25 (PYTHIA, 172.5GeV/c2, 6.72M)
  • dtops0 (HERWIG, 172.5GeV, 5.6M)

Status: Done PE !

Parton Distrubution Functions

By Reweighting 46 files
Refer to Joint Physics Page
  1. Generate reweighting root files:
    • Go to
      (you have to make sure you have the compiled topToPdfWeights.exe which you can follow the Joint Physics Page.
      Also refer to /cdf/s13/hslee/top_width/PDF_systematics/outfiles
    • Make a text file of a list of ttop25 strpped files(contain the 'TopTree' information) and an empty folder for output root files
      Then run
      ./topToPdfWeights.exe   list=ttop25_stripList.txt   dir=./reWeightOutfiles_ttop25
  2. Generate reweighting files based on the above reweighting root files
    • Go to /cdf/s13/tangjian/Analysis/summer2010/Systematics/PDF/TMTRel/topToPdfWeights and use pdfweight_generate.C to generate 46 reweighting files
    • Copy these 46 reweighting files to kdewidth dir and ready to submit PE jobs, refer to in dir /cdf/s13/tangjian/TopWidth/spring2009/biascheck/myKDErelease/TMTCode/kdewidth
Just use code PDF_ana.C, the results are on the last line of output.
Error of Error:
Using bootstrap results

Status: PEing !

B Jet Energy Scale

  1. Cal. Response
    • ttop25_bes0.99.root
    • ttop25_bes1.01.root
  2. Semi-Leptonic BRs
    • Nominal twid15
    • weight_bsig10_csig10
    • weight_bsig-10_csig-10
  3. b-Fragmentation
    • Nominal ttop25
    • sldw
    • adow
  1. Cal. Response
    • Templating using a different ""(example: /cdf/s13/tangjian/Analysis/summer2010/Systematics/bJES/bjes_templating/scripts)
    • Point: multiply every E or Pt related to b-quark by 0.99 or 1.01; "control file" should contain a parameter "bes 0.99" or "bes 1.01"
    • Also refer to dir
  2. Semi-Leptonic AND b-Fragmentation
      Generate reweighting files
    • Every templating code dir contains "BSpackage", with "BSpackage.hh","" and "", also "bfragweight.dat".
    • Compile /cdf/s13/tangjian/Analysis/summer2010/Systematics/bJES/bjes_templating/scripts/(stripped ttop25 files will be used)
    • reweighting files of bsig10_csig10, bsig-10_csig_-10, adow and sldw will be generated.
    • Do normal reweighting PEs with these files.
Error of Error:
Standard_Formula_of_Error_Propagation X Nominal_RMS/sqrt(3000)

Status: Done PE!

Background Fraction and Shape

::Different from L+Jets and DIL::

Background Normalization
A), Background Error:
There is error when calculating the expected num of bkgd events, so scale the bkgd num up and down by one sigma(without changing the shape of bkgd Poisson constraint)

B), Background Shape:
The total num of observed events is not the same as the num of expected events, so add the difference to the num of bkgd events(nevtfile) when doing PE

Background Modeling

Background Normalization:

A), Background Error:
Scale up & down the 'nbkgd' number to be used in PE within uncertainty
go to /cdf/s13/tangjian/Analysis/summer2010/METJ_KDE/myKDErelease/TMTCode/kdecode/
and find a line with nbkgd = myRandom_again->Poisson(nbkgdexp); and multiply this 'nbkgd' by a scale factor.
To calculate this scale factor, calculate the ratio 'R'=(Error of num of expected bkgd)/(Num of expected bkgd), then 1+R is the 'Up' scale factor and 1-R is the 'Down' scale factor, and half of the difference of the PE result is the systematic.(the idea is to scale the num of bkgd events up and down by one sigma without shifting the Poisson bkgd constraint shape).
A), Background Norm:
We take this as systematic b/c the num of expected events are too different from the num of observed events. So we account the difference to the num of bkgd in the 'nevtfile_observed' file and redo the PE

Background Modeling:

The basic idea is to tilde the shape of bkgd as much as possible(up and down)
go to
and generate the reweighting files(up and down).
Error of Error:
2 X Nominal_RMS/sqrt(3000)

Status: !

Trigger Simulation

::This systematic is just for METJets::

By reweighting
Use the probup and probdown of signal events to tilde the signal shape, just like the bkgd modeling systematic
and generate the reweighting files(up and down).
Error of Error:
2 X Nominal_RMS/sqrt(3000)

Status: Done PE!

ggbar Fusion Fraction

By Reweighting
    How to generate gg fusion fraction reweighting file :
  1. Dump run and event number of ggbar events from stripped ttop25 file
    • Use, compile it by adding it in "Makefile" in /cdf/s13/tangjian/Analysis/summer2010/METJets_templating/scripts
    • The stripped ttop25 files(contain 'TopTree' tree in its root file) are in /cdf/s13/tangjian/Analysis/summer2010/METJ_templating_Dec03rd/ttop25_stripped/outfiles (I had trouble adding all these root files together).
    • After executing "./gg_hepgInfo", you will have 62 event files: events_file_**, also you will see calculated wight from screen.
  2. Now ready to generate events from pure gg fusion and events not from gg fusion, out of default ttop25 samples
    • Refer to /cdf/s13/tangjian/Analysis/summer2010/Systematics/gg_fusion, use normal_eventsfile_generate.C to generate all events from "ttop25_0.0.root"
    • Use to merge events that only come from gg fusion, named "gg_events_within_normal_file", and then generate events not from gg fusion, named "normal_without_gg".
      NOTE:You have to remove the new line symbol from the last line of files "events_file_**" or any other event file. Also note that shell commands "sort" and "uniq" help a lot.
  3. Now ready to write weight for each event
    • Refer to /cdf/s13/tangjian/Analysis/summer2010/METJ_templating_Dec03rd/TMTRel/scripts, use write_weight_into_file.C to write weight 1.0(for non-gg events) or 3.**(for gg events) for files "gg_events_within_normal_file" and "normal_without_gg"
      NOTE: the reweighting file has this format --
      samplenum bgtype run event weight
      where samplenum is 0 ... 6 (so 4 and 5 means subsample4 and subsample5), bgtype here you can set it to be -1
    • Finally merge the two weighting files using shell command "cat", and you are done !

Now you have gg fusion reweighting files, just do PE as others

gg reweighting
gg events fraction of ttop25: 6.185%
gg weight: 3.2336

Error of Error:
2 X Nominal_RMS/sqrt(3000)

Status: Done PE!

ISR/FSR Radiation

  • dtops1 (more ISR/FSR)
  • dtops2 (less ISR/FSR)
Error of Error:
Using bootstrap results

Status: Done PE!

Monte Carlo Statistics

    Get the results from BiasCheck and bootstrap
  • Signal Statistics
  • Bkgd Statistics
Error of Error:

Status: Done PE!

Multiple Hadron Interactions

MC Sample -- ttop25: Reweighting
  • nvetx = 1
    (if nvetx==1, let the weight be 1, otherwise 0)
  • nvetx = 2
  • nvetx = 3
  • nvetx >= 4
  1. Generate reweighting files
    • Use code "makeReweightingFile.C" to generate reweighting files
    • Refer to /cdf/s13/tangjian/Analysis/summer2010/Systematics/pileup
  2. PE using reweighting files
Error of Error:
Nominal RMS/sqrt(3000)

Status: Done PE!

Color Reconnection

Difference between:
  • ctopsd: PYTHIA, Apro, 172.5GeV, 6.72M
  • ctopse: PYTHIA, ACRpro, 172.5GeV, 6.72M
  • ctopsb: PYTHIA, S0 Perugia0, 172.5GeV, 6.72M
  • ctopsc: PYTHIA, NOCR Perugia, 172.5GeV, 6.72M
Error of Error:
Using bootstrap

Status: Done PE!