Transcript ZimanyiSchool2008novlong

HIGH challenges in LOW energy HADRON physics
G. Vesztergombi
Zimanyi School
Budapest, 25 November 2008
OUTLINE
AA
-Landscape
-STAR plans
pp,pA
-Static quarks
-High pT below 20 GeV
-NA61
-CBM
-QGP in pp
-Barion versus parton propagation
AA
pp,pA
Science 21 November 2008: Vol. 322. no. 5905, pp. 1224 – 1227
Ab Initio Determination of Light Hadron Masses
S. Dürr,1 Z. Fodor,1,2,3 J. Frison,4 C. Hoelbling,2,3,4 R. Hoffmann,2 S.
D. Katz,2,3 S. Krieg,2 T. Kurth,2 L. Lellouch,4 T. Lippert,2,5 K. K.
Szabo,2 G. Vulvert4
More than 99% of the mass of the visible universe is made up of protons and neutrons.
Both particles are much heavier than their quark and gluon constituents, and the
Standard Model of particle physics should explain this difference. We present a full ab
initio calculation of the masses of protons, neutrons, and other light hadrons, using
lattice quantum chromodynamics. Pion masses down to 190 mega–electron volts are
used to extrapolate to the physical point, with lattice sizes of approximately four times
the inverse pion mass. Three lattice spacings are used for a continuum extrapolation.
Our results completely agree with experimental observations and represent a
quantitative confirmation of this aspect of the Standard Model with fully controlled
uncertainties.
Latest in LATTICE QCD
PENTA ?
All baryonic states listed in PDG can be made of 3 quarks only
* classified as octets, decuplets and singlets of flavour SU(3)
* Strangeness range from S=0 to S=-3
A baryonic state with S=+1 is explicitely EXOTIC
• Cannot be made of 3 quarks
•Minimal quark content should be qqqqs , hence pentaquark
•Must belong to higher SU(3) multiplets, e.g anti-decuplet
observation of a S=+1 baryon implies a new large multiplet of
baryons (pentaquark is always ocompanied by its large family!)
important
Searches for such states started in 1966, with negative
results till autumn 2002 [16 years after 1986 report of PDG !]
Searches were for heavy and wide states
Motivation for new measurements below
s = 20 GeV
Practically no high or medium Pt data between Einc = 24 and 200 GeV
Mysterious transition around 80-90 GeV: convex versus concave spectra
Energy threshold for Jet-quenching?
Emergence of Cronin-effect in pA interactions is completely unknown
energy dependence
centrality dependence
particle type dependence
particle correlations
Production of Upsilon (9.5 GeV) particles near the threshold.
Beier (1978)
NA49 (CERN) results at 158
FODS (IHEP) at 70 GeV
RA+A/p+A
CRONIN-effect removed by p+A baseline
NEW !!!
Pb+Pb, 0-12.7% most central
p+Pb reference

preliminary
WA98 and NA49 data presented in QM'06 by Gianluca USAI's plenary talk
NA61
Study of Hadron Production in Hadron-Nucleus and Nucleus-Nucleus Collisions at
the CERN SPS
SPOKESPERSON: Marek GAZDZICKI
SPOKESPERSON: Gyoergy VESZTERGOMBI
GLIMOS:
Beam:
Approved:
Status:
Zoltan FODOR
(Technical coordinator)
21-FEB-07
Preparation
CERN Greybook 2008
Benchmark NA49 pp at E = 158 GeV
Events
Energy
2 106
158
> 3 GeV/c
100
30 events/spill
> 4 GeV/c
1
> 5 GeV/c
0.01
Estimates with the assumption 1011 proton/sec 109 interaction/sec
1 day=1014
158
5 109
5 107
5 105
CBM Perspectives
10-1
10-2
90
5 108
5 105
20 day=2 1015 90
1010
107
104
10-3
10-6
10-10
107
10
Suppression
1 day=1014
Suppression
20 day=2 1015 45
10-3
500
0
For symmetric nuclei max energy 90/2 assumed
Special requirements for Y-> e+e- and high pT
Extremely high intensity
-
Pile-up
Segmented multi-target
-
Relaxed vertex precision
Straight tracks
-
High momentum tracks
DREAM: 109 interactions/sec
QGP in pp?
Átlag pT (Van Hove)
Részecskeszám (Van Hove)
Multiplicity
Single FIRE-BALL = QGP?
A
(AB)*
B
Double FIRE-BALL = Factorization?
B*
A
B
A*
BARION propagation through the NUCLEUS
A
N**
N*
A*
N
A**
Npart = 3+1
HADRON
PROPAGATION
Ncoll = 3
Npart/2 = (13+12)/2 =12.5
Ncoll = (36+28)/2 = 32
HADRON PROPAGATION
(Some diffractive binary collisions included)
PHENIX
Ncoll
Au-Au
=1
Npart Au-Au= 1
200 GeV
Npart d-Au =Ncoll d-Au
Earlier Cronin-effect at higher energies: 2 -> 1 GeV/c
Pizero smaller Cronin-effect.