Jet quenching, Nov' 2003

1
Jet quenching, Nov. 2003
hep-ph/0310079 CERN-TH-2003-244
2
During last VRVS meeting I suggested to look at
http//www-cdf.fnal.gov/physics/talks_transp/2003
/cipanp_qcd_mesropian.pdf
3
http//www-cdf.fnal.gov/physics/talks_transp/2003/
cipanp_qcd_mesropian.pdf
4
http//www-cdf.fnal.gov/physics/talks_transp/2003/
cipanp_qcd_mesropian.pdf
Higher pT jets are more focused
5
http//www-cdf.fnal.gov/physics/talks_transp/2003/
cipanp_qcd_mesropian.pdf
6
Medium Modification of Jet Shapes and Jet
Multiplicities Salgado, C A Wiedemann, U A
hep-ph/0310079 CERN-TH-2003-244
Distribution of gluons radiated from initial hard
parton
Soft gluons dominate and they populate small pT
k2k2/ (mean pT2 transferred from the medium to
the projectile on the length L
7
Medium Modification of Jet Shapes and Jet
Multiplicities Salgado, C A Wiedemann, U A
hep-ph/0310079 CERN-TH-2003-244
Observable
Vacuum shapes from Fixed cone jet definitions in
D0 and R(sep) Abbott, B- D0 Collaboration.FERMIL
AB-Pub-97-242-E
8
Medium Modification of Jet Shapes and Jet
Multiplicities Salgado, C A Wiedemann, U A
hep-ph/0310079 CERN-TH-2003-244
Jet (not subjet) E resolution 50/?E2 for 50
GeV 9 for 100 GeV 7
Calo granularity
i.e. L32 !?!
9
Medium Modification of Jet Shapes and Jet
Multiplicities Salgado, C A Wiedemann, U A
hep-ph/0310079 CERN-TH-2003-244
I have a challenged child and I know what it
means
10
Medium Modification of Jet Shapes and Jet
Multiplicities Salgado, C A Wiedemann, U A
hep-ph/0310079 CERN-TH-2003-244
Some optimism
Partonic jet multiplicity is a new perspective
11
Medium Modification of Jet Shapes and Jet
Multiplicities Salgado, C A Wiedemann, U A
hep-ph/0310079 CERN-TH-2003-244
Upper limit of radiated gluons energy
A visible broadening!
12
Medium Modification of Jet Shapes and Jet
Multiplicities Salgado, C A Wiedemann, U A
hep-ph/0310079 CERN-TH-2003-244
Pesimism? Optimism? A challenge
13
But we will always have some averaging
TA(b).TB(b) driving the probability of a jet
creation
Pb
Pb
TA(b)TB(b) driving the density of the medium (no
expansion here)
14
Some references
A Dynamical Scaling Law for Jet Tomography
/Salgado, C A Wiedemann, U Ahep-ph/0204221
CERN-TH-2002-086.- Geneva CERN, 18 Apr 2002 . -
4 p   Published in Phys. Rev. Lett. 89 (2002)
092303/1-4 On the Angular Dependence of the
Radiative Gluon Spectrum /Baier, R Dokshitzer,
Yu L Müller, A H Schiff, D hep-ph/0105062  
Published in Phys. Rev., C 64 (2001) 057902
Energy Loss of Hard Partons in Nuclear Matter
/Wiedemann, Urs Ahep-ph/0103332 30 Mar 2001 .
Published in Nucl. Phys., A 698 (2002)
615-618 Jet Quenching versus Jet Enhancement a
Quantitative Study of the BDMPS-Z Gluon Radiation
Spectrum /Wiedemann, Urs Ahep-ph/0008241
Published in Nucl. Phys., A 690 (2001)
731-51 Gluon Radiation off Hard Quarks in a
Nuclear Environment Opacity Expansion
/Wiedemann, Urs A hep-ph/0005129   Published in
Nucl. Phys., B 588 (2000) 303-344. Hard
Probes in Heavy Ion Collisions at the LHC Jet
Physics /Accardi, A et al.hep-ph/0310274 23 Oct
2003 . - 123 p