HIGH challenges in LOW energy HADRON physics G. Vesztergombi Zimanyi School Budapest, 25 November 2008.

HIGH challenges in LOW energy HADRON physics

G. Vesztergombi

Zimanyi SchoolBudapest, 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

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 , hence pentaquark•Must belong to higher SU(3) multiplets, e.g anti-decuplet

qqqqs

Searches for such states started in 1966, with negativeresults till autumn 2002 [16 years after 1986 report of PDG !]

observation of a S=+1 baryon implies a new large multiplet of baryons (pentaquark is always ocompanied by its large family!)

important

Searches were for heavy and wide states

PENTA ?

Motivation for new measurements below = 20 GeVs

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 dependencecentrality dependenceparticle type dependenceparticle correlations

Production of Upsilon (9.5 GeV) particles near the threshold.

NA49 (CERN) results at 158FODS (IHEP) at 70 GeV

Beier (1978)

preliminary

Pb+Pb, 0-12.7% most central

p+Pb reference

WA98 and NA49 data presented in QM'06 by Gianluca USAI's plenary talk

RA+A/p+A

CRONIN-effect removed by p+A baseline

NEW !!!

SPOKESPERSON: Marek GAZDZICKI

SPOKESPERSON: Gyoergy VESZTERGOMBI

GLIMOS: Zoltan FODOR

Beam:

Approved:   21-FEB-07

Status: Preparation

NA61

Study of Hadron Production in Hadron-Nucleus and Nucleus-Nucleus Collisions at the CERN SPS

CERN Greybook 2008

(Technical coordinator)

Benchmark NA49 pp at E = 158 GeV 30 events/spill Events Energy > 3 GeV/c > 4 GeV/c > 5 GeV/c

2 106 158 100 1 0.01Estimates with the assumption 1011 proton/sec 109 interaction/sec

1 day=1014 158 5 109 5 107 5 105

Suppression 10-1 10-2 10-3

1 day=1014 90 5 108 5 105 500

20 day=2 1015 90 1010 107 104

20 day=2 1015 45 107 10 0

Suppression 10-3 10-6 10-10

For symmetric nuclei max energy 90/2 assumed

CBM Perspectives

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?

Részecskeszám (Van Hove)

Átla

g pT

(V

an H

ove)

Multiplicity

Single FIRE-BALL = QGP?

A B(AB)*

Double FIRE-BALL = Factorization?

A B

A*

B*

BARION propagation through the NUCLEUS

A

A*

A**N

N*

N**

HADRON PROPAGATION

Npart = 3+1 Ncoll = 3

HADRON PROPAGATION

Npart/2 = (13+12)/2 =12.5

Ncoll = (36+28)/2 = 32

(Some diffractive binary collisions included)

PHENIX 200 GeV

Ncoll = 1

Npart = 1

Npart =Ncoll

Au-Au

Au-Aud-Au d-Au

Earlier Cronin-effect at higher energies: 2 -> 1 GeV/c

Pizero smaller Cronin-effect.