Fortran HERWIG Status Report

and Validation in Athena rel. 14

By

Jon Butterworth (UCL)

Claire Gwenlan (Oxford)

Alessandro Tricoli (RAL)

ATLAS MC Generator Meeting, 11th December 2008

HERWIG status reportHERWIG status report

Many changes in Herwig_i interfaceMany changes in Herwig_i interface from last MC Validation Meeting:From Herwig_i-00-03-03 to Herwig_i-00-03-15

– some related to Charybdis and Alpgensome related to Charybdis and Alpgen

• Fixes in Herwig_i-00-03-10 Fixes in Herwig_i-00-03-10

– addition of Horace to the interface as external generator:addition of Horace to the interface as external generator:

• In Herwig_i-00-3-13In Herwig_i-00-3-13

– addition of RPV code to Herwig (in a seperate library):addition of RPV code to Herwig (in a seperate library):

• in Herwig_i-00-3-10, fixes in Herwig_i-00-3-12in Herwig_i-00-3-10, fixes in Herwig_i-00-3-12

– fix of the Low Mass Z "ears" in etafix of the Low Mass Z "ears" in eta

• ME correction did not preserve the rapidity of the vector boson in the hard process. Large effect for small x (corrections are enhanced by 1/x)ME correction did not preserve the rapidity of the vector boson in the hard process. Large effect for small x (corrections are enhanced by 1/x)

• Modified routine hwbdyp.f (ME corrections for DY processes) in Herwig_i-00-03-13Modified routine hwbdyp.f (ME corrections for DY processes) in Herwig_i-00-03-13

• bug-fix release of Fortran Herwig “Herwig 6.511” due to come out soon. bug-fix release of Fortran Herwig “Herwig 6.511” due to come out soon.

– fix of the Higgs->WW decays:fix of the Higgs->WW decays:

• reported by the Higgs group, fixed by Bryan Webber and Jon Butterworth, and checked by Tiesheng Dai in Herwig_i-00-03-15reported by the Higgs group, fixed by Bryan Webber and Jon Butterworth, and checked by Tiesheng Dai in Herwig_i-00-03-15

• Bug in the fix corrected in Herwig_i-00-03-15Bug in the fix corrected in Herwig_i-00-03-15

– several changes & fixes to the parameter setting in the interface:several changes & fixes to the parameter setting in the interface:

• More steerable parametersMore steerable parameters

• Latest fixes in Herwig_i-00-03-15 Latest fixes in Herwig_i-00-03-15

Latest TagsHerwig_i-00-03-15 ← CVS tag HEADHerwig_i-00-03-13 ← 14.4.0.1 release

HERWIG status reportHERWIG status reportLow Mass Z Rapidity “ears”

old version of hwbdyp.f new version of hwbdyp.f

Test done by Claire Gwenlan in Fortran Herwig stand-alone (before its implementation in ATHENA)The fix has to be checked withn ATNENA (to do list)

HERWIG HERWIG SMSM validation status report validation status reportSample B (14.4.0.1) AODsSample B (14.4.0.1) AODs Herwig_i-00-03-13: valid1.105100.JimmyWenu.recon.a78 MC8 series (10 TeV)

500K events!! (Thanks to Osamu)

W and Electron plots look OK: comparison OK with 10 TeV ref. plots from previous Sample B (14.2.0.2, conf tag a64)

((see extra slides for more plots)see extra slides for more plots)

Private production 14.4.0.1Private production 14.4.0.1 Herwig_i-00-03-15Herwig_i-00-03-15: : (small samples)(small samples)

W→e sample Comparison OK with Herwig_i-00-03-13 (Sample B) for W and Electron plots

Z→ee sample Z and Electron distributions look OK

W rapidity W pT

14.4.0.1 (Sample-B 10 TeV)

14.2.0.1 (REF, Sample-B 10 TeV)

Ra

tio

Ra

tio

HERWIG HERWIG SUSYSUSY validation status report validation status reportSample B (14.4.0.1) AODsSample B (14.4.0.1) AODs Herwig_i-00-03-13: valid1.105403.SU3_jimmy_susy.recon.a78 MC8 series (10 TeV)

plots look OK compared to ref. plots from previous SampleB (14.2.20.1, config tag a70)

more plots in extras

C4 truth jets

MET

electrons muons

EXTRA SLIDES

Sample-B Plots

rel 14.4.0.1, 10 TeV, config tag a78500K events

UsingMC8.105100.JimmyWenu.py

csc_evgenTruthJetMet08_trf.py

Thanks to Osamu!!

Compared to previous 10 TeV Sample-B:rel 14.2.0.2, 10 TeV, config tag a64

50 K events

valid1.105100.JimmyWenu.recon.a78

HERWIG SM validation

W Boson14.4.0.1 (Sample-B 10 TeV)

14.2.0.1 (REF, Sample-B 10 TeV)

W pT

W MassW y

Ra

tio

Ra

tio

Ra

tio

HERWIG SM validation W± Bosons

W- yW+ y

14.4.0.1 (Sample-B 10 TeV)

14.2.0.1 (REF, Sample-B 10 TeV)

W+ pT W- pT

Ra

tio

Ra

tioR

atio

Ra

tio

HERWIG SM validation Final State Electrons (status==1)

From W decay

e- e+

e±

14.4.0.1 (Sample-B 10 TeV)

14.2.0.1 (REF, Sample-B 10 TeV)

Ra

tio

Ra

tio

Ra

tio

HERWIG SM validation Final State Electrons (status==1)

From W decay

e- e+

ele pT

14.4.0.1 (Sample-B 10 TeV)

14.2.0.1 (REF, Sample-B 10 TeV)

Ra

tio

Ra

tio

Ra

tio

HERWIG SM validation Charge Asymmetry in W events

W

Electron

W+ - W-

W+ + W-

e+ - e-

e+ + e-

14.4.0.1 (Sample-B 10 TeV)

14.2.0.1 (REF, Sample-B 10 TeV)

Ra

tioR

atio

Sample-B Plots

rel 14.4.0.1, 10 TeV, config tag a7850K events

UsingMC8.105403.SU3_jimmy_susy.py

csc_evgenTruthJetMet08_trf.py

Thanks to Osamu!!

Compared to previous 10 TeV samples (all 50K events):- rel 14.2.20.1 SampleB, 10 TeV, config tag a70 - rel 14.2.0.2 SampleB, 10 TeV, config tag a64- rel 12.0.6, 10 TeV (privately produced)

valid1.105403.SU3_jimmy_susy.recon.a78

MET quantities

HERWIG SUSY validation

Note: samples from 14.4.0.1 and 14.2.20.1 use the new SUSY SU3 spectrum/decay file

14.2.0.2 and 12.0.6 use the old s/d file, but are shown here to illustrate differences arising from those different files

[ for further details on the old versus new spectrum/decay files see fHerwig status report from 9th Sept 2008]

electron quantities

HERWIG SUSY validation

slight spread in electron mass in 14.4.0.1?

muon quantities

HERWIG SUSY validation

photon quantities

HERWIG SUSY validationDifferences observed presumably due to the fact that pions from taus were not being decayed in previous rel14 samples (see fHerwig report from 9th Sept. 2008). This is now fixed…

dilepton masses

HERWIG SUSY validation

OSSF elecs+muons SSSF elecs+muons

OSSF electrons OSSF muons

jet quantities

HERWIG SUSY validation