W JamboreeEric Lançon - ALEPH Week - January 2001 1 Jetset vs Herwig … Once more III Jetset vs...
23
W Jamboree Eric Lançon - ALEPH Week - January 2 001 1 Jetset vs Herwig … Once more III Jetset vs Herwig on same selected events
-
Upload
stephanie-wilkinson -
Category
Documents
-
view
214 -
download
0
Transcript of W JamboreeEric Lançon - ALEPH Week - January 2001 1 Jetset vs Herwig … Once more III Jetset vs...
W Jamboree Eric Lançon - ALEPH Week - January 2001
1
Jetset vs Herwig… Once more III
Jetset vs Herwig on same selected events
W Jamboree Eric Lançon - ALEPH Week - January 2001
2
Conclusions from 14-June-2000
• More reconstructed energy (300 MeV) with Herwig
• More charged energy in Herwig (300 MeV)– Calibration of Eflow? Herwig Z0 events
needed– Explain difference in efficiency
• Larger particle multiplicity in Jetset• Jetset jets are wider
– More losses are low/high
• Jetset resolution worst than Herwig• Jet-Jet angle larger for Herwig than JetsetWhich of the two MC data prefer?
Herwig BugHerwig Bug
W Jamboree Eric Lançon - ALEPH Week - January 2001
3
What’s new
• HERWIG bugs have been fixed by G. Rudolph
• 1 M Jetset and Herwig same CC03 events have been produced over Christmas by Marcello
• Today : rapid comparison Jetset vs Herwig
• With new common Ntuples
W Jamboree Eric Lançon - ALEPH Week - January 2001
4
Total Event energy
300 Mev more energy in Herwig
•Pb of Eflow calibration?•Need Herwig Z0 events
This explain the higher efficiency of the selection for Herwig ?
14-June-20
00
W Jamboree Eric Lançon - ALEPH Week - January 2001
5
Total Event energy
300 Mev more energy in Herwig
Still there
Notice the small Jetset difference : +0.1 GeV
W Jamboree Eric Lançon - ALEPH Week - January 2001
6
Charged energy
300 Mev less charged energy in Jetset
14-June-20
00
W Jamboree Eric Lançon - ALEPH Week - January 2001
7
Charged energy
500 Mev less charged energy in Jetset
Notice the Jetset difference : +1.48 GeV
W Jamboree Eric Lançon - ALEPH Week - January 2001
8
Charge multiplicity
0.16 more charged particles in Jetset
14-June-20
00
W Jamboree Eric Lançon - ALEPH Week - January 2001
9
Charge multiplicity
0.1 more charged particles in Herwig
Notice the Jetset difference : +2.36
W Jamboree Eric Lançon - ALEPH Week - January 2001
10
Multiplicity per jet
Nb of charged tracks/jet Nb of Eflow objects/jet
More objects/jet in Jetset
14-June-20
00
W Jamboree Eric Lançon - ALEPH Week - January 2001
11
Multiplicity per jet
Nb of charged tracks/jet Nb of Eflow objects/jet
More objects/jet in Herwig More objects/jet in Jetset
Total Number of objects now
W Jamboree Eric Lançon - ALEPH Week - January 2001
12
resolutionBetter resolution for Herwig
(rec.-gen.)
<> = -0.019 0.009RMS = 6.22
<> = -0.006 0.008RMS = 5.51
14-Jun
e-2000
W Jamboree Eric Lançon - ALEPH Week - January 2001
13
resolution(rec.-gen.)
<> = -0.033 0.009RMS = 6.25
<> = -0.022 0.008RMS = 6.30
Similar resolution for Herwig
???
W Jamboree Eric Lançon - ALEPH Week - January 2001
14
(raw-generated) vs gen.
Z
generated
Herwig
Jetset(rec.-gen.) vs gen.
• Jetset jets are more inside• Herwig jets less biased at low 14
-June-20
00
W Jamboree Eric Lançon - ALEPH Week - January 2001
15
(raw-generated) vs gen.
(rec.-gen.) vs gen.• Jetset jets are a still bit less inside
W Jamboree Eric Lançon - ALEPH Week - January 2001
16
Sum of Pt2
Jets JetParticles
TP 2
Wider Jetset jets
14-June-20
00
W Jamboree Eric Lançon - ALEPH Week - January 2001
17
Sum of Pt2
Jets JetParticles
TP 2
a bit Wider HERWIG jets
Notice the small Jetset difference : -0.135 GeV
W Jamboree Eric Lançon - ALEPH Week - January 2001
18
Jet-jet angle
Jet1
Jet2
Herwig Ws are more ‘opened’
= -0.32 0.04 deg.
Strongly related to W mass
14-June-20
00
W Jamboree Eric Lançon - ALEPH Week - January 2001
19
Jet-jet angle
Jet1
Jet2
This has been cured !
Strongly related to W mass
= 0.01 0.03 deg.
Notice the small Jetset difference : +0.42 deg.
W Jamboree Eric Lançon - ALEPH Week - January 2001
20
Fitted mass : Herwig - JetsetMHerwig - Mjetset = 7 7 MeV
Before rescaling
Super!
W Jamboree Eric Lançon - ALEPH Week - January 2001
21
Delta fitted mass vs Nb jets in BarrelMJetset - MHerwig vs number jets in barrel
3
9
2.5
14-June-20
00
W Jamboree Eric Lançon - ALEPH Week - January 2001
22
Delta fitted mass vs Nb jets in Barrel
MJetset - MHerwig vs number jets in barrel
W Jamboree Eric Lançon - ALEPH Week - January 2001
23
Temporary conclusions
• Quick look at recently produced Jetset and Herwig MC samples
• Most of the differences between Jetset and Herwig have been cured
• At first look : the net result is NO mass shift between the two fragmentation models
• However : some differences between new and old Jetset produced evts observed – Need to be understood– Effect of common Ntuple reconstruction ?We are on better shape!
