Herwig++ in Gauss Philip Ilten University College Dublin Bucharest - - PowerPoint PPT Presentation

Herwig++ in Gauss

Philip Ilten

University College Dublin

Bucharest MC Workshop November 23, 2012

Ilten (UCD) Herwig++ in Gauss November 23, 2012 1 / 15

Introduction : Overview

Overview

❼ Herwig++:

❼ Powheg weighting NLO matrix elements: ❼ Higgs production ❼ vector boson pair production ❼ q¯ q′ → W → f ¯ f ′, q¯ q → γ/Z → f ¯ f ❼ MatchBox NLO framework (experimental) ❼ full polarization mechanism ❼ sophisticated decay models ❼ cluster hadronization (better for heavy flavor) ❼ different ISR and FSR methods from Pythia ❼ different underlying event and MPI

❼ Resources:

❼ Herwig++: Physics and Technical Aspects ❼ Herwig++ Physics and Manual ❼ Herwig++ API ❼ ThePEG API

Ilten (UCD) Herwig++ in Gauss November 23, 2012 2 / 15

Introduction : Matrix Elements

LO Matrix Elements

Name Process MEDISCC charged current deep inelastic scattering MEDISNC neutral current deep inelastic scat- tering MEMinBias simple color singlet exchange MEQCD2to2 pp → X1 + X2 MEgg2ff gg → f ¯ f MEHeavyQuark pp → b¯ b/t¯ t MEGammaGamma pp → γγ MEGammaJet pp → γ + jet MEPP2VGamma pp → W/Z + γ MEPP2VV pp → WW/ZZ/WZ MEWJet pp → W + jet MEZJet pp → Z + jet MEgg2WW gg → WW MEqq2W2ff q¯ q → W → f ¯ f MEqq2gZ2ff q¯ q → γ∗/Z → f ¯ f

Ilten (UCD) Herwig++ in Gauss November 23, 2012 3 / 15

Introduction : Matrix Elements

LO Higgs Matrix Elements

Name Process MEHiggs gg/qg → H MEHiggsJet pp → H + jet MEPP2HiggsVBF pp → WW/ZZ → H MEPP2WH pp → WH MEPP2ZH pp → ZH MEPP2bbbarH pp → b¯ bH MEPP2ttbarH pp → t¯ tH

Ilten (UCD) Herwig++ in Gauss November 23, 2012 4 / 15

Introduction : Matrix Elements

NLO Matrix Elements

Name Process PowhegMEHiggs gg/gq → H PowhegMEPP2HiggsVBF pp → WW/ZZ → H PowhegMEPP2VV pp → WW/ZZ/WZ PowhegMEPP2WH pp → WH PowhegMEPP2ZH pp → ZH PowhegMEqq2W2ff q¯ q → W → f ¯ f PowhegMEqq2gZ2ff q¯ q → γ∗/Z → f ¯ f

Ilten (UCD) Herwig++ in Gauss November 23, 2012 5 / 15

Introduction : Polarization

Polarization

2 ρj

λjλ′

j = ρ1

κ1κ′

1ρ2

κ2κ′

2

× Mκ1κ2;λ1...λnM∗

κ′

1κ′ 2;λ′ 1...λ′ n

× Y

k=j

Dk

λkλ′

k

3 Wdecay = ρλ0λ′

0Mλ0;λ1...λnM∗

λ′

0;λ′ 1...λ′ n

× Y

k=1,n

Dk

λkλ′

k

5 Dλ0λ′

0 = Mλ0;λ1...λnM∗

λ′

0;λ′ 1...λ′ n

× Y

l=1,n

Dl

λlλ′

l

initial interaction

e+ e− γ τ − τ + ντ ¯ ντ W + W − e− ¯ νe u ¯ d

decay decay

2Eπ−/√s

0.2 0.4 0.6 0.8 1

Nevents

2000 4000 6000 8000 10000 12000 14000 16000 Z H W H± Ilten (UCD) Herwig++ in Gauss November 23, 2012 6 / 15

Introduction : Decays

Decays

Nevents

10000 20000 30000 40000 50000 60000 70000 80000

q¯ q′ → W − → τ − → ντπ−π+K−

Pythia 8 Herwig++ Tauola

q¯ q′ → W − → τ − → ντπ−π+K− mπ−π+K− [GeV/c2 ]

0.8 1 1.2 1.4 1.6 1.8

• 3

3

Nevents

20 40 60 80 100 120 3 10

q¯ q′ → W − → τ − → ντπ0π−π−π+

Pythia 8 Herwig++ Tauola

mπ0π−π+ [GeV/c2 ]

0.4 0.6 0.8 1 1.2 1.4 1.6

• 3

3

Ilten (UCD) Herwig++ in Gauss November 23, 2012 7 / 15

Implementation : Gauss Package

Gauss Package

❼ Gauss/Gen/LbHerwigpp

# = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = u s e G e n e r a t o r s v ✯ G e n u s e h e r w i g++ v ✯ → L C G _ G e n e r a t o r s I n t e r f a c e s u s e t h e p e g v ✯ → L C G _ G e n e r a t o r s I n t e r f a c e s # = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = m a c r o h e r w i g++_ n a t i v e _ v e r s i o n "→ 2 . 5 . 1 " m a c r o t h e p e g _ n a t i v e _ v e r s i o n "→ 1 . 7 . 1 " # = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = l i b r a r y L b H e r w i g p p c o m p o n e n t / ✯ . c p p # = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = a p p l y _ p a t t e r n c o m p o n e n t _ l i b r a r y → l i b r a r y=L b H e r w i g p p

❼ cmt

❼ requirements - CMT

configuration ❼ src/component

❼ HerwigppProduction -

actual production source ❼ src/Lib

❼ GaudiRandomForHerwigpp

• legacy random number

interface

Ilten (UCD) Herwig++ in Gauss November 23, 2012 8 / 15

Implementation : Methods

Methods

❼ initialize ❼ initializeGenerator ❼ finalize ❼ generateEvent ❼ toHepMC ❼ setStable ❼ updateParticleProperties ❼ turnOnFragmentation ❼ turnOffFragmentation ❼ hadronize ❼ savePartonEvent ❼ retrievePartonEvent ❼ printRunningConditions ❼ isSpecialParticle ❼ setupForcedFragmentation

Ilten (UCD) Herwig++ in Gauss November 23, 2012 9 / 15

Implementation : Random Numbers

Random Numbers

❼ No direct interface with Herwig++ (GaudiRandomForHerwigpp). ❼ Clear and reset ThePeg random number generator per event. ❼ Set the seed from Gauss.

// Set the random seed . i n t r n d = m _ r a n d o m . s h o o t ( ) ✯ I N T _ M A X ; // Flush the Herwig++ random g e n e r a t o r . m _ h e r w i g p p − >a c c e s s R a n d o m ( )− >f l u s h ( ) ; // Set the Herwig++ random g e n e r a t o r seed . m _ h e r w i g p p − >a c c e s s R a n d o m ( )− >s e t S e e d ( r n d ) ; Ilten (UCD) Herwig++ in Gauss November 23, 2012 10 / 15

Implementation : Defaults

Defaults

❼ Use min-bias simple color singlet exchange. ❼ Not tuned! ❼ Use Herwig++ for min-bias, pile-up?

" i n s e r t / H e r w i g / M a t r i x E l e m e n t s / S i m p l e Q C D : M a t r i x E l e m e n t s [ 0 ] / H e r w i g /→ M a t r i x E l e m e n t s / M E M i n B i a s " " s e t / H e r w i g / C u t s / J e t K t C u t : M i n K T 0 . 0 * G e V " " s e t / H e r w i g / C u t s / Q C D C u t s : M H a t M i n 0 . 0 * G e V " " s e t / H e r w i g / C u t s / Q C D C u t s : X 1 M i n 0 . 0 5 5 " " s e t / H e r w i g / C u t s / Q C D C u t s : X 2 M i n 0 . 0 5 5 " " s e t / H e r w i g / U n d e r l y i n g E v e n t / M P I H a n d l e r : I d e n t i c a l T o U E 0 " " s e t / H e r w i g / U n d e r l y i n g E v e n t / M P I H a n d l e r : s o f t I n t Y e s " " s e t / H e r w i g / U n d e r l y i n g E v e n t / M P I H a n d l e r : t w o C o m p Y e s " " s e t / H e r w i g / U n d e r l y i n g E v e n t / M P I H a n d l e r : D L m o d e 3 " Ilten (UCD) Herwig++ in Gauss November 23, 2012 11 / 15

Validation : Configuration

Configuration

❼ Locally generated NLO Powheg f ¯

f → Z → µ−µ+.

❼ Full simulation, digitization, and reconstruction. ❼ Options file:

G e n e r a t i o n . E v e n t T y p e = 42122011; G e n e r a t i o n . P i l e U p T o o l = ✬ F i x e d L u m i n o s i t y ✬ ; G e n e r a t i o n . D e c a y T o o l = ✬ ✬ ; G e n e r a t i o n . S a m p l e G e n e r a t i o n T o o l = ✬ S p e c i a l ✬ ; G e n e r a t i o n . S p e c i a l . C u t T o o l = ✬ ✬ ; G e n e r a t i o n . S p e c i a l . D e c a y T o o l = ✬ ✬ ; G e n e r a t i o n . S p e c i a l . P r o d u c t i o n T o o l = ✬ H e r w i g p p P r o d u c t i o n ✬ ; G e n e r a t i o n . S p e c i a l . H e r w i g p p P r o d u c t i o n . O u t p u t L e v e l = 2 ; G e n e r a t i o n . S p e c i a l . H e r w i g p p P r o d u c t i o n . C o l l i d i n g B e a m s . B e a m M o m e n t u m = → 3500000; G e n e r a t i o n . S p e c i a l . H e r w i g p p P r o d u c t i o n . C o m m a n d s += { ✬ # E n a b l e N L O Z b o s o n p r o d u c t i o n . ✬ , ✬ cd / H e r w i g / M a t r i x E l e m e n t s / ✬ , ✬ s e t P o w h e g M E q q 2 g Z 2 f f : G a m m a Z Z ✬ , ✬ s e t P o w h e g M E q q 2 g Z 2 f f : P r o c e s s M u o n ✬ , ✬ i n s e r t S i m p l e Q C D : M a t r i x E l e m e n t s [ 0 ] P o w h e g M E q q 2 g Z 2 f f ✬ , ✬ # S e t c u t s . ✬ , ✬ s e t / H e r w i g / C u t s / L e p t o n K t C u t : M i n E t a 2 . 0 ✬ , ✬ s e t / H e r w i g / C u t s / L e p t o n K t C u t : M a x E t a 5 . 0 ✬ , ✬ s e t / H e r w i g / C u t s / L e p t o n K t C u t : M i n K T 2 0 . 0 * G e V ✬ } ; Ilten (UCD) Herwig++ in Gauss November 23, 2012 12 / 15

Validation : Z Variables

Z Variables

[GeV]

Z

M 60 70 80 90 100 110 120 0.05 0.1 0.15 0.2 0.25 0.3

MC10 Herwig++

φ ∆ 0.5 1 1.5 2 2.5 3 0.05 0.1 0.15 0.2 0.25 0.3

MC10 Herwig++

Z

η 2 3 4 5 6 7 8 9 10 0.02 0.04 0.06 0.08 0.1

MC10 Herwig++

[GeV]

Z T

p 5 10 15 20 25 30 35 40 45 50 0.02 0.04 0.06 0.08 0.1 0.12

MC10 Herwig++

Ilten (UCD) Herwig++ in Gauss November 23, 2012 13 / 15

Validation : µ Variables

µ Variables

[GeV]

1

µ T

p 20 30 40 50 60 70 80 0.02 0.04 0.06 0.08 0.1 0.12 0.14

MC10 Herwig++

[GeV]

2

µ T

p 10 20 30 40 50 60 0.02 0.04 0.06 0.08 0.1 0.12 0.14

MC10 Herwig++

[GeV]

1

µ

isolation 1 2 3 4 5 6 7 8 9 10 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45

MC10 Herwig++

[GeV]

2

µ

isolation 1 2 3 4 5 6 7 8 9 10 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4

MC10 Herwig++

Ilten (UCD) Herwig++ in Gauss November 23, 2012 14 / 15

Conclusion

Conclusion

❼ Herwig++ fully integrated with Gauss. ❼ Should update to version 2.6. ❼ Not tuned! ❼ Default PDF set to use? ❼ What are the requested processes? ❼ What timeline is necessary?

Ilten (UCD) Herwig++ in Gauss November 23, 2012 15 / 15