4 th international workshop on vhmp, alushta 2 june 2003 carmine elvezio pagliarone a j u m p i n t...
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44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
A jump into the
A jump into the
Future !Future !
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
VLHCVLHCthe Very Large Hadron the Very Large Hadron
ColliderCollider
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Concept:Concept: 2 stages project2 stages project
Stage 1: Stage 1: Build a BIG TUNNEL, fill with a “cheap” Build a BIG TUNNEL, fill with a “cheap” 40 40 TeVTeV machine; machine; Stage 2: Stage 2: Later upgrade it to Later upgrade it to 200 TeV200 TeV;;
Place:Place: Fermilab (?)Fermilab (?)
Take advantage of the space and excellent Take advantage of the space and excellent geology geology around Fermilab;around Fermilab; Use the avaiable facilities;Use the avaiable facilities;
When:When: 2020 (?)2020 (?)
TESLA (2013)TESLA (2013)
Cost (ECB): Cost (ECB): ~ 4130 M$ ~ 4130 M$ (3790 M$ for SSC Y2001$)(3790 M$ for SSC Y2001$)
2004
2004
2009
2009
2013
2013
VLHCVLHC
TESLA/LCTESLA/LC
2020
2020
US US ExpensesExpenses
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
200200
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
FermilabFermilab
MichiganMichiganLakeLake
TevatronTevatron
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
why Fermilab ?
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
MB studies for Detector & Trigger use - Comparison of
Pythia and Isajet(E4-WG3 Detectors)
- Understand the particle/Energy flux, Multiplicity, PUnderstand the particle/Energy flux, Multiplicity, PTT, , <P<PTT>…>…- Which Rapidity Region we have to cover ?Which Rapidity Region we have to cover ?- How well MC Generators do ? (what is your How well MC Generators do ? (what is your opinion?)opinion?)- … … only then start to think about a VHM Triggeronly then start to think about a VHM Trigger
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Total Cross Section
Physical Process s=40 TeVs=100
TeVs=175
TeVs=200
TeV
Elastic Cross Section - - - -
Single DiffractiveSingle Diffractive 7.60 mb7.60 mb 7.96 mb7.96 mb 8.17 mb8.17 mb 8.22 mb8.22 mb
Double DiffractiveDouble Diffractive 11.38 mb11.38 mb 12.83 mb12.83 mb 13.73 mb13.73 mb 13.95 mb13.95 mb
Low PLow PTT Processes Processes -- -- -- --
Inelastic Cross SectionInelastic Cross Section 93.07 mb93.07 mb 107.1 mb107.1 mb 116.7 mb116.7 mb 119.2 mb119.2 mb
Total Cross Section - - - -
PYTHIA 6.129
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Total Cross Section
Physical Process s=40 TeVs=100
TeVs=175
TeVs=200
TeV
Elastic Cross Section - - - -
Single Diffractive - - - -
Low PT Processes - - - -
Inelastic Cross Section
137 mb 157 mb - 174 mb
Total Cross Section - - - -
ISAJET 7.51
“No hard scattering at all; events consist only of beam jets. To represent the total cross section it’s better to use a sample of TWOJET events with lower limit on PT chosen to give a cross section equal to the inelastic cross section or to use a mixture of MINIMUM BIAS and TWOJET events” - ISAJET Manual
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
hep-ph 0011157
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Generated 20000 Minimum Bias events at 4 center of mass energies: s= 40,100,175,200 TeV;
Used both Isajet and Pythia Monte Carlo Program
no Detector Simulation (toy or other) taken into account;
considered only charged tracks;
mean PT of the event defined as:
<PT> evaluated considering different cuts on the minimum track PT;
Event particle density:
N
j
jTT P
NP
1
1
N
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Rapidity Distributions
Pythia 6.129
A
rb.
Un
its
Arb
. U
nit
s
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Isajet 7.51
Rapidity Distribution
A
rb.
Un
its
Arb
. U
nit
s
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Rapidity – Pythia vs Isajet
s=40 TeV
A
rb.
Un
its
Arb
. U
nit
s
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Rapidity – Pythia vs Isajet
s=100 TeV
A
rb.
Un
its
Arb
. U
nit
s
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Rapidity – Pythia vs Isajet
s=200 TeV
A
rb.
Un
its
Arb
. U
nit
s
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
PPTT Distribution of Charged Particles Distribution of Charged Particles
CMECME <<PPTT>>s= 40s= 40 TeVTeV 0.45 GeV/c0.45 GeV/c
s= 100s= 100 TeVTeV 0.49 GeV/c0.49 GeV/c
s= 200s= 200 TeVTeV 0.53 GeV/c0.53 GeV/c
Pythia 6.129
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Charged particles <PT>
PT> 1.0 GeV/c
PPTT> 5.0 > 5.0 GeV/cGeV/c
Pythia 6.129
any PT
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Energy Flow
101033
101022
101011
101000
-10 -8 -6 -4 -2 0. 2. 4. 6. 8. 10.-10 -8 -6 -4 -2 0. 2. 4. 6. 8. 10.
En
erg
y [
GeV
]En
erg
y [
GeV
]
Almost all the Energy is in the Forward Region of Almost all the Energy is in the Forward Region of
Energy Flow, 100 TeV, 1 Energy Flow, 100 TeV, 1 EventEvent
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Average Number of Charged Tracks
100100
1010.01 .1 1 10 100 1000.01 .1 1 10 100 1000
s [TeV]s [TeV]
Ch
arg
ed
C
harg
ed
M
ult
iplicit
yM
ult
iplicit
yPythia 6.129
VLHCVLHC
<Multiplicity> = 125 <Multiplicity> = 125 (@ 100 (@ 100 TeV)TeV)
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Number of tracker “elements”Number of tracker “elements”
for 100-200 TeV of CME the expected number of tracks for 100-200 TeV of CME the expected number of tracks is:is:
NNtrktrk ~ 50 x 100 = 5x10 ~ 50 x 100 = 5x10 33
(interactions per bunch crossing)(interactions per bunch crossing)
For reasonable reconstruction/triggering, occupancy For reasonable reconstruction/triggering, occupancy below 1%below 1% is needed:is needed:
NNElemElem ~ 5 x 10 ~ 5 x 1033 x 10 x 102 2 = 5x10= 5x105 5 Elements/LayerElements/Layer
A number of Layer > 20 is needed:A number of Layer > 20 is needed:
NNElemElem ~ 5 x 10 ~ 5 x 1055 x 2x10 x 2x10 = 10= 107 7 number of tracker “elements”number of tracker “elements”
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Number of tracker “elements”Number of tracker “elements”
special low luminosity runs are necessary to avoid special low luminosity runs are necessary to avoid multiple multiple interactions;interactions;
in principle such a tracking system should be able to in principle such a tracking system should be able to reach reach reasonable high values of Z.reasonable high values of Z.
How trustable are these MC Simulations ?How trustable are these MC Simulations ?
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Mean transverse momentum vs multiplicity
CDF CDF DataData
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Mean Transverse momentum vs multiplicity (MC)
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Simulated and Reconstructed inclusive distributions poorly match the Experimental Data (CDF MB @ 1.8 TeV);
The shape of the <PT> vs multiplicity correlation is roughly reproduced,
But <PT> values are considerably lower than the measured ones.
How well PYTHIA do ?How well PYTHIA do ?
44thth International Workshop on VHMP, International Workshop on VHMP, Alushta 2 June 2003Alushta 2 June 2003 Carmine Carmine Elvezio PagliaroneElvezio Pagliarone
Conclusions
cross sections and multiplicities changing with energy cross sections and multiplicities changing with energy increaseincrease very slowly;very slowly;
Multiplicity distributions have long non-Gaussian tails;Multiplicity distributions have long non-Gaussian tails;
Most of charged tracks are low momentum: Most of charged tracks are low momentum: <p<pTT> ~ 0.6 > ~ 0.6 GeVGeV;;
@ 100 TeV Pythia @ 100 TeV Pythia predictpredict a mean charged track a mean charged track multiplicity multiplicity
of of 125125;;
All the studied parameters and distributions are used to All the studied parameters and distributions are used to
evaluate the behaviour of the Monte Carlo… we could evaluate the behaviour of the Monte Carlo… we could seesee
surprizes at very high energy.surprizes at very high energy.