Документ взят из кэша поисковой машины. Адрес оригинального документа : http://qfthep.sinp.msu.ru/talks/GRACE.pdf Дата изменения: Fri Sep 10 22:14:38 2010 Дата индексирования: Mon Oct 1 19:31:55 2012 Кодировка: Поисковые слова: trees

Status of GRACE Development
Y. Kurihara (KEK) GRACE-Group
Title of Presen @Q 11/Sep./2010tation FTHEP2010 r Name You Your Title Golitsyno, Moscow, Russia tion (Line #1) Your Organiza
Your Organization (Line #2)

2005-12-31


Outline
Introduction What is GRACE ? GRACE for SUSY Processes QCD Event-Generators for LHC Summary

2


Introduction
Automatic Calculation Systems This year is 20 's Anniversary ! GRACE meets CompHEP at AIHENP1990 @ Lyon Battle Field of "LEP-II War" @ 1995 Tree to Loop Leptons to Quarks SM to BSM

No ACS, No Physics !
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What is GRACE ?

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What is GRACE? : Structure
.fin .mdl .rin

User input
Kinematics library

Diagram generator
diagram description

model file

Theory Drawer

amplitude generator
LOOP symbolic code
REDUCE, Form etc.

Make file etc.

TREE

Diagrams (figure)

PS file

FORTRAN code kinematics code

generated code
parameter file

Library CHANEL, loop

convergence information

BASES(MC integral)
Cross sections distributions

SPRING (EG manager)

Events
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What is GRACE? : Model File 1

6


What is GRACE? : Model File 2

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What is GRACE? : Input File
Name of model file loop order tree order Order of Order of s initial state particles

final state particles kinematics number
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What is GRACE? : Diagrams

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What is GRACE? : FORTRAN Code

10


What is GRACE? : Integration

Integration Result (pb)

Accuracy (%)
11


What is GRACE? : Distributions
Energy Distribution
GNU Plot

Simple Histo. by ASCII Char.

12


What is GRACE? : Event Generation
Numerical Integration by BASES Probability Density Matrix

Event Generation W/ unit Weight LH Accord Interface

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GRACE for SUSY

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GRACE for SUSY : Gauge Fixing
Full Lagrangean of MSSM =
MSSM

+

GF-V

+

GF-S

+ C

T

Non-linear Gauge Fixing : Gauge bosons = -|FW|2/W + FZ2/(2Z) + F2/(2) GF-V ~ ~A ± igc Z )W ± µ FW ± = ( µ ± ie µ W µ g ~0 ~ 0 ~0 ± ± iW ( + h h + H H ± i G )G 2 gZ µ ~ ~ FZ = µ Z + Z (v + h h 0 + H H 0 )G 0 2 F = µ Aµ

J.Fujimoto et al., Phys.Rev.D75, 113002('07) 15


GRACE for SUSY : Gauge Fixing
Non-linear Gauge Fixing : S-leptons
GF-S

=

16


GRACE for SUSY : Renomarization
Electro-weak corrections On-Mass-Shell scheme
mass shifts for h0, H±,
0 2,3,4

only

Sfermion sector

17


GRACE for SUSY : Renomarization
QCD corrections

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GRACE for SUSY : System Check
Non-linear Gauge Check (One Phase Point) Ex. for One-Loop ~~ ~ ~~ ~ ~, , , , , , ) NLG Parameters : ( h H h H
Case 1 : (0,0,0,0,0,0,0) Ans = 0.15117115752797127186610833503954323 Case 2 : (1000,2000,3000,4000,5000,6000,7000) Ans = 0.15117115752797127186610833480863836

Unit[GeV]
K.Iizuka, et al, POS(RADCOR2009)068[hep-ph/1001.2800]
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GRACE for SUSY : System Check
Ex. for One-Loop (One Phase Point) UV-Cancellation Check
Case 1 : (Cuv=1/=0) Ans = 0.15117115752797127186610833503954323 Case 2 : (Cuv=1000) Ans = 0.15117115752797127186596180279397801

IR-Cancellation Check
Case 1 A ns = Case 2 A ns = : ( =10-24) 0.15117115752797127186610833503954323 : ( =10-27) 0.15117115752797127186610833519983020
K.Iizuka, et al, POS(RADCOR2009)068[hep-ph/1001.2800] 20


GRACE for SUSY : System Check
Ex. for
Cuv (GeV) kc (GeV) loop soft hard sum correction 0
10
-24 -3

One-Loop : (After Integration)
1000
10
-24 -3

Electro-weak correction
0
10
-27 -3

0
10
-24 -5

10

10

10

10

-0.06256 0.21373 0.04849 0.19966 13.9%

-0.06256 0.21373 0.04849 0.19966 13.9%

-0.09364 0.24481 0.04849 0.19966 13.9%

-0.06256 0.19301 0.06921 0.19966 13.9%
21

K.Iizuka, et al, POS(RADCOR2009)068[hep-ph/1001.2800]


GRACE for SUSY : System Check
Ex. for
Cuv Cir loop soft hard sum correction

One-Loop : (After Integration)
0 0 -1.254 -3.752 4.905 -0.100 -7.1% 1 0 -1.254 -3.752 4.905 -0.100 -7.1% 0 1 -1.479 -3.527 4.905 -0.100 -7.1%

QCD Correction

K.Iizuka, et al, POS(RADCOR2009)068[hep-ph/1001.2800]
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GRACE for SUSY : Example

K.Iizuka, et al, POS(RADCOR2009)068[hep-ph/1001.28023 0]


GRACE for SUSY : Example

M. Jimbo, et al, [hep-ph/1006.3491] 24


GRACE for SUSY : Example

Threshold

2-body 3-body

M. Jimbo, et al, [hep-ph/1006.3491]

25


GRACE for SUSY : Example
+ ~ ~ t b 1 1

tree

(%)

m~ (GeV) t1
T. Koike, et al, [JPS Meeting 2010/09/12]
26


GRACE for SUSY : Example
~ +~ t b 1

tree

(%)

m~ (GeV) t1
T. Koike, et al, [JPS Meeting 2010/09/12]
27


GRACE for LHC

28


GRACE for LHC : GR@PPA 2.7
W + jets (up to 3 jets) with the subsequent W decay Z + jets (up to 2 jets) with the subsequent Z decay Four bottom quarks top-quark pair with the subsequent decay di-boson (WW, WZ and ZZ) with the subsequent W/Z decay

29


GRACE for LHC : GR@PPA 2.8
New features of GR@PPA 2.8
ME-PS matching in the generation of W, Z, W+W­,

ZW, ZZ production processes at hadron collisions
LLL subtraction & custom LL PS Forward evolution PS in the initial state (QCDPS) Backward evolution PS (QCDPSb) available as well Final-state PS (QCDPSf) also implemented as well as initial-state radiations.

30


GRACE for LHC : GR@PPA 2.8
Additional features
W and Z decays in the matrix elements
Exact spin, phase-space and off-shell effects at the tree level PDG values for the decay widths and branching ratios of W and Z Generated events can be passed to PYTHIA to proceed the simulation : hadronization and decays

Still at LO : Please wait GR@PPA 3.0 It can be downloaded from: http://atlas.kek.jp/physics/nlo-wg/grappa.html

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GRACE for LHC : GR@PPA 2.8
Z-boson production

The D0 data and the simulation are normalized to the CDF cross section.
32


GRACE for LHC : GR@PPA 2.8
Di-boson production @LHC : GR@PPA v.s. MC@NLO

W+W W+W ZW ZZ
­

­

ZW ZZ

Plots: GR@PPA 2.8 + PYTHIA 6.419 Solid lines : MC@NLO3.31+Herwig6.510.3+Jimmy4.31.3
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GRACE for LHC : NLO Generator
ME PS Matching @ NLO
·

Process : uu+-(+gluon) in pp collision Cuts: s>40GeV kTg> 1 GeV

:[µ µ g] PDF (w/Double Counting)
*



:[µ µ g(NLO)]



PS

:[µ µ (t+v+c)]/PS



:[µ µ g-LL]



PS
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GRACE for LHC : NLO Generator
Transverse momentum distribution of W-jet

Full correction

Real radiation (LL subtraction)

Tree+Virtual correction 35


GRACE for LHC : NLO Generator
Transverse momentum distribution of
Full correction

Real radiation (LL dubtraction) Tree+Virtual correction

36


GRACE for LHC : NLO Generator
Direct Processes

Lowest Process

Loop Correction

Real Radiation

Diphox
T. Binoth, J.Ph. Guillet, E. Pilon, M. Werlen Eur. Phys. J. C16, 311 (2000)
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GRACE for LHC : NLO Generator
Fragmentation Processes



DIPHOX Fragmentation Function Inclusive Jet No Event-Generation GR@PPA Parton Shower (QCD/QED) Event-Generation

single fragmentation

double fragmentation

38


GRACE for LHC : QCED PS
gg

f

Q2

g q

g

n

g

QCD

QCD partonShower q
Jets

q2/fc /


s

PS-1

q
39


GRACE for LHC : QCED PS
Random choice

gg

f

Q2

g q

g

n

g

QCD

QCD partonShower q
Jets

q2/fc /


s

PS-2

q
40


GRACE for LHC : QCED PS
gg

f

Q2

q

q

n

QCD

q

g QCD partonShower g
Jets

4% gqq

1 1 x 2 2 k T 1- x

2

41


GRACE for LHC : QCED PS
Q2=(50 GeV)~(5
PS
3 2.5

) , Egluon = 100GeV QCD
*
ME calc. uu g* dd PS

2

Log(ds/dpT)

1.5

1

0.5

0 0 0.2 0.4 0.6 0.8 1 1.2

pT (GeV)

jet pT

energy

42


GRACE for LHC : QCED PS
Q2=(50 GeV)~(5 energy
PS-1 PS-2 FF
QCD

) , Equark = 100GeV

E

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Summary
GRACE is a Automatic Generator of Generators QED, Electro-weak SM, QCD, MSSM @ 1-Loop order GR@PPA 2.8 Full Exclusive unweighted Hadron Event Generator w/ MEPS Matching 2.8 3.0 : NLO +QECD PS Full Exclusive unweighted Event Generator

44