experimental overview Federico Antinori INFN Padova CERN Federico

experimental overview Federico Antinori (INFN Padova & CERN) Federico Antinori - Levoča - 29 jún 2007 1

Disclaimer l This selection is biassed and incomplete: l l too much material, not enough time I concentrated on flavour results and my personal selection at that in particular: in preparing this talk l l I have not tried to be ecumenical I have tried to share with you what I’ll take home from this beautiful conference Federico Antinori - Levoča - 29 jún 2007 2

Contents l Strangeness l Quarkonia l Heavy Flavour l Conclusions Federico Antinori - Levoča - 29 jún 2007 3

Strangeness Federico Antinori - Levoča - 29 jún 2007 4

Motivácia l l s particle production suppressed (wrt production of light flavour) in elementary collisions removal of suppression large system should ease enhancement l if strangeness can be conserved over a large volume l i. e. : correlation volume large! (e. g. : quarks freed in QGP) l l if AA were simple superposition of pp no enhancement K+ if sistem deconfined and particles built Xby recombination, expect larger p+ enhancement for multi-strange enhancement increasing with s content W+ [Rafelski: Phys. Rep. 88 (1982) 331] [Rafelski-Müller: P. R. Lett. 48 (1982) 1066] [Koch, Müller & Rafelski: Phys. Rep. 142 (1986) 167] d su u u d d d d ss us d u d d d u u s u u d s uu s s ud d d ss u u s d u u s s d us u d u s sd d u u d d p- p 5

Hyperon enhancements l top SPS NA 57 NA 49 Christoph Blume Giuseppe Bruno l centrality dependence also important to constrain models ! l e. g. : “canonical suppression model” fast saturation with centrality [Hamieh et al. : Phys. Lett. B 486 (2000) 61] Federico Antinori - Levoča - 29 jún 2007 6

l energy dependence also constrains models e. g. much weaker than predicted by canonical suppression model: Redlich et al. , JPG 28 (2002) 2095 X 40 Ge. V 10 160 Ge. V 1 Federico Antinori - Levoča - 29 jún 2007 Giuseppe Bruno (NA 57) 7

Hyperon enhancements @ RHIC l still strong, a bit lower than @ SPS l l open: NA 57 @ SPS closed: STAR @ RHIC Lee Barnby (STAR) Federico Antinori - Levoča - 29 jún 2007 8

Now also Cu-Cu l similar to Au-Au l l open: Au-Au (STAR) closed: Cu-Cu (STAR) Jun Takahashi (STAR) Federico Antinori - Levoča - 29 jún 2007 9

and also for Φ l role of canonical suppression? Nu Xu (STAR) Federico Antinori - Levoča - 29 jún 2007 10

RCP @ SPS l Larger than @ RHIC NA 49 preliminary PHENIX NA 49 preliminary -0. 3 < y < 0. 7 NA 49 preliminary Christoph Blume (NA 49) Federico Antinori - Levoča - 29 jún 2007 11

RCP @ SPS l l no evidence for high p. T suppression (RCP < 1) but similar relative K 0 S/ pattern as at RHIC Giuseppe Bruno (NA 57) Federico Antinori - Levoča - 29 jún 2007 12

l Relative Λ, K 0 S Rcp pattern ~ independent of √s, coll. system Jun Takahashi (STAR) Federico Antinori - Levoča - 29 jún 2007 13

K 0 S from NA 45 l New approach: l does not use separation of K 0 S vertex from primary use all (+, -) combinations S/B ~ 10 -3 subtract mixed-events bckg and sensitivity at low p. T l l Sylwester Radomski (NA 45) Federico Antinori - Levoča - 29 jún 2007 14

Sylwester Radomski (NA 45) Federico Antinori - Levoča - 29 jún 2007 15

NA 57 -NA 49 -NA 45 kaon comparison l not too bad… ½(K++K-) NA 49 0 -5% scaled to 0 -10% Giuseppe Bruno (NA 57) K 0 s NA 57 0 -11% NA 49 0 -10% NA 45 0 -7% scaled to 0 -10% NA 49 Nucl. Phys. A 715 (2003) 453 c, QM 2002 NA 49 Phys. Rev. C 66, 054902 (2002) Federico Antinori - Levoča - 29 jún 2007 NA 57 Jour. Phys. G 31 (2005) 1345 -1357 NA 45 S. Radomski Ph. D. thesis 16

Recombination triumphant l l multi-strange enhancements kinetic evidence from nq scaling of v 2, RCP l (+ KET at low momentum) Phys. Rev Lett. 98, 162301 (2007) Hugo Pereira (PHENIX) Federico Antinori - Levoča - 29 jún 2007 17

a flea in the ontiment? l shower (S) + thermal (T) recombination l Ω- mostly from TTT (shower s suppressed) [RC Hwa & CB Yang nucl-th/0602024] no Ω- in jets? Federico Antinori - Levoča - 29 jún 2007 Betty Abelev (STAR) but Ω- shows same side peak… 18

…Fyre Burn & Cauldron Bubble… l Ye Thermal Fyttes Are Doing Well! l (as usual…) l e. g. STAR, using Thermus 200 Ge. V 62. 4 Ge. V Jun Takahashi (STAR) Federico Antinori - Levoča - 29 jún 2007 19

l remarkable regularity in freeze-out systematics Jean Cleymans Federico Antinori - Levoča - 29 jún 2007 20

Thermal parameters vs y? l e. g. : baryon density Michael Murray (BRAHMS) d. N/dy chemistry depends on y AGS SPS “net”proton l RHIC 62 (BRAHMS preliminary) RHIC 200 LHC 5500 Federico Antinori - Levoča - 29 jún 2007 21

Thermal parameters vs y! Jean Cleymans l how to interpret T, µB from “ 4π”fits? Federico Antinori - Levoča - 29 jún 2007 22

Low SPS energy anomalies? l a. k. a. “the horn” [Marek Gazdzicki (NA 49) QM 04] Jan Rafelski (+ the step, the jump, the kink, the stomp, the bump, the whoopee…) new expeditions to the region are being organized Federico Antinori - Levoča - 29 jún 2007 23

Lower energy still… l again, thermal fit very good… l Al+Al @ 1. 9 A Ge. V (FOPI) l chemical T < kinetic T Al+Al THERM. MOD. : . A. Andronic et al. , NPA 772 (2006) 167 Xavier Lopez (FOPI) Federico Antinori - Levoča - 29 jún 2007 l exception to systematics? 24

Resonances chemical freeze-out f p p * re-scattering p * K regeneration f leptonic decay kinetic freeze-out hadronic decay K K signal measured late decay K signal lost p K e+ e- signal measured early decay time Christina Markert (STAR) Federico Antinori - Levoča - 29 jún 2007 25

Resonance suppression Christina Markert (STAR) Life-time [fm/c] : K(892) = 4. 0 S(1385) = 5. 7 (1520) = 13 (1020) = 45 l can we extract information on system timescales? Federico Antinori - Levoča - 29 jún 2007 26

K* v 2 l Agrees better with n=2 l expect n=4 from Kπ coalescence Christina Markert (STAR) Federico Antinori - Levoča - 29 jún 2007 27

Mass shifts? l e. g. : STAR K* l ~ 10 Me. V shift observed at low p. T could we be onto something? STAR Preliminary MC Patricia Fachini PDG K*0 PDG K*± l same effect also in pp… Federico Antinori - Levoča - 29 jún 2007 28

Caveat… l 10 Me. V shift comparable with typical size of instrumental effects… e. g. : l l NA 45 K 0: a few Me. V l Federico Antinori - Levoča - 29 jún 2007 NA 57 K 0: a few Me. V STAR D 0 from e – D 0 analysis: ~ 25 Me. V D 0+D 0 29

The SPS Φ puzzle (NA 49 vs NA 50) l News from NA 60: better agreement with NA 49, at least at low p. T NA 60 In-In (p. T > 1. 1 Ge. V/c) NA 49 Pb-Pb NA 50 Pb-Pb [NA 45 - PRL 96 (2006) 152301] NA 60 In-In (p. T < 1. 6 Ge. V/c) NA 49 Pb-Pb NA 50 Pb-Pb Michele Floris (NA 60) l Absolute yield in progress Federico Antinori - Levoča - 29 jún 2007 l Similar conclusion from NA 45 30

Quarkonia (& dileptons) Federico Antinori - Levoča - 29 jún 2007 31

J/ψ suppression l present status: SPS RHIC LHC more cc reco dominates? F. Karsch et al. : PLB 637 75 (2006) larger e J/y finally melts? l very similar suppression at RHIC and SPS. . . l l only y’and cc melt? J/y melting compensated by cc recombination? Federico Antinori - Levoča - 29 jún 2007 l at LHC we should finally be able to tell. . . 32

J/y: RAA at large rapidity l NA 50 at SPS (0<y<1) PHENIX at RHIC (|y|<0. 35) PHENIX at RHIC (1. 2<|y|<2. 2) l Larger suppression at larger rapidity What controls suppression? l l energy density? …? Hugo Pereira (PHENIX) Federico Antinori - Levoča - 29 jún 2007 33

Υ in STAR • unlike-sign pairs — like-sign pairs Lee Barnby (STAR) Federico Antinori - Levoča - 29 jún 2007 34

Intermediate mass excess (NA 60) l Fit weighted impact parameter distribution l prompt from J/ψ dimuons, charm from PYTHIA l requires > 2 x expected D-Y to fit data H. Woehri and C. Lourenco, Phys. Rep. 433 (2006) 127 -180 Michele Floris (NA 60) 6500 A, 2 match < 3 l l NA 60 sensitivity to assumption on cc p. T, Δφ extracted value of cc cross section ~ 2 – 3 larger than extrap. l but compatible with extrapolation from NA 50 p-A Federico Antinori - Levoča - 29 jún 2007 35

Intermediate mass excess (NA 60) l Centrality and p. T distribution of excess Michele Floris (NA 60) Federico Antinori - Levoča - 29 jún 2007 36

PHENIX di-leptons l Low mass enhancement! l + intermediate mass suppression? p+p Christian Klein-Bösing (PHENIX) Federico Antinori - Levoča - 29 jún 2007 Au+Au minimum bias Watch this space! 37

Heavy Flavour Federico Antinori - Levoča - 29 jún 2007 38

Motivácia l study medium with probes of known colour charge and mass l l l study effect of medium on fragmentation (no extra production of c, b at hadronization) l l e. g. : energy loss by gluon radiation expected to be: parton-specific: stronger for gluons than quarks (colour charge) flavour-specific: stronger for lighter than for heavier quarks (dead -cone effect) independent string fragmentation vs recombination e. g. : D+s/D+ + measurement important for quarkonium physics l l open QQ production natural normalization for quarkonium studies B meson decays non negligible source of non-prompt J/ y Federico Antinori - Levoča - 29 jún 2007 39

Experimental techniques @ RHIC Federico Antinori - Levoča - 29 jún 2007 40

Non-photonic electrons l Identified electron spectra l STAR: d. E/dx in TPC + TOF at low p. T, EMC at high p. T PHENIX: combined RICH and E/p (with E from EM cal) Rejection of non-heavy-flavour electrons l Main source of electrons: “photonic” l l estimated by simulation and subtracted (“cocktail method”) measured by “converter method” and subtracted Other sources of non-charm electrons: l rejected by full invariant mass analysis of e+e- combinations PHENIX: l l (“internal conversions”) STAR: l g e+e- conversions Dalitz decays p 0 e+e-g Dalitz decays h e+e-g w, r, j, K decays estimated by sim. and subtracted (in both STAR and PHENIX) Federico Antinori - Levoča - 29 jún 2007 41

Reconstructed decays (STAR) l l l D 0 K-p+ tracks from TPC K, p identification from d. E/dx no separation of D decay vertex large combinatiorial background evaluated by event mixing and subtracted that still leaves substantial background, subtracted with linear fit Andre Mischke (STAR) Federico Antinori - Levoča - 29 jún 2007 42

Low p. T muons (STAR) 1. m/p in TPC (d. E/dx) 2. m/p in TOF 3. fit to impact parameter distribution l [C Zhang (STAR) QM 06] charm m should ~ point to primary. . . Federico Antinori - Levoča - 29 jún 2007 43

Experimental status Federico Antinori - Levoča - 29 jún 2007 44

PHENIX pp l Excess wrt FONLL: l Similar situation also in CDF: Dong. Jo Kim (PHENIX) Ratio: 1. 72 0. 02 (stat) 0. 19 (sys) (0. 3 < p. T < 9. 0 Ge. V/c) D 0 [A. Adare et al. (PHENIX) Phys. Rev. Lett. 97 (2006) 252002] [D. Acosta et al. (CDF) PRL 91 (2003) 241804] 45

STAR v PHENIX pp l ~ a factor 2 discrepancy hep-ex/0609010 [J. Lajoie (PHENIX) QM 06] Federico Antinori - Levoča - 29 jún 2007 46

STAR d. Au, Au. Au l Internal consistency Lee Barnby (STAR) [M. Calderon (STAR) QM 06] Federico Antinori - Levoča - 29 jún 2007 47

STAR v PHENIX d. Au, Au. Au l Discrepancy pretty “stable” v collision system, channel, p. T l looks like something very basic. . . Federico Antinori - Levoča - 29 jún 2007 [A. Suaide QM 06] 48

a curiosity… l STAR yield larger than PHENIX yield for Φ STAR Patricia Fachini PHENIX STAR + PHENIX Federico Antinori - Levoča - 29 jún 2007 49 J. Rafelski et al. , Phys. Rev. C 72 (2005) 024905

STAR v PHENIX d. Au, Au. Au l l l Discrepancy pretty “stable” v system, p. T looks like something very basic. . . of course then RAA not too different. . . Federico Antinori - Levoča - 29 jún 2007 [A. Suaide QM 06] 50

STAR v PHENIX: RAA l RAA of non-photonic electrons [A. Suaide QM 06] similar picture from STAR and PHENIX Federico Antinori - Levoča - 29 jún 2007 51

Interpretations Federico Antinori - Levoča - 29 jún 2007 52

Theoretically. . . average energy loss Casimir coupling factor distance travelled in the medium transport coefficient of the medium R. Baier et al. , Nucl. Phys. B 483 (1997) 291 (“BDMPS”) Energy loss for heavy flavours is expected to be reduced: i) Casimir factor l l light hadrons originate from a mixture of gluon and quark jets, heavy flavoured hadrons originate from quark jets CR is 4/3 for quarks, 3 for gluons ii) dead-cone effect l gluon radiation expected to be suppressed for q < MQ/EQ [Dokshitzer & Karzeev, Phys. Lett. B 519 (2001) 199] [Armesto et al. , Phys. Rev. D 69 (2004) 114003] Federico Antinori - Levoča - 29 jún 2007 53

Experimentally. . . l l l non ph. el. ~ as suppressed as light hadrons use of high density (qhat), introduction of elastic (in addition to radiative) energy loss. . . not enough high qhat and no beauty electrons does better [B. I. Abelev et al (STAR): nucl-ex/0607012] Federico Antinori - Levoča - 29 jún 2007 54

How much beauty? [M. Cacciari et al. : PRL 95 (2005) 122001] l l high p. T region expected to be beauty-dominated but how “high”? [A. Suaide QM 06] l Federico Antinori - Levoča - 29 jún 2007 not easy to disentangle c/b contributions to RHIC non ph. el. samples (no heavy flavour vertex detectors in RHIC experiments) 55

e-h correlations in STAR l idea: MB > MD larger transverse kick for B electrons less pronounced correlation in B wrt D decays l Xiao Yan Lin (STAR) nice idea, of course relies heavily on l l understanding of purity of “non ph. el. ” accuracy of simulation l taken at face value: FONLL ratio ~ OK l but then B also enhanced? e-h from B e-h from D Fit [X. Y. Lin: hep-ph/0602067] [X. Y. Lin: QM 06] from simulation of PYTHIA events Federico Antinori - Levoča - 29 jún 2007 56

New approach l electron-D 0 correlations in STAR (in pp) Andre Mischke (STAR) Federico Antinori - Levoča - 29 jún 2007 57

By the way: the factor 9/4? l l l Federico Antinori - Levoča - 29 jún 2007 energy loss should be proportional to: CR = 4/3 for q, = 3 for g at RHIC, at 6 -8 Ge. V p. T: x ~ 10 -1 large quark contribution also for light flavours? at LHC, at same p. T: x ~ a few 10 -4 quark contribution negligible 58

E loss being understood? Federico Antinori - Levoča - 29 jún 2007 Dong. Jo Kim (PHENIX) 59

another sobering caveat… l Relative abundances in charm sector also important: BR (X e) in % D 0 17. 2 1. 9 D Ds+ c + 6. 71 0. 29 8 +6 -5 4. 5 1. 7 l c/D l Sebastien Gadrat e. g. : Λc/D may change from pp to AA and what about Ds? l s enhancement! (e c)/(e D) Federico Antinori - Levoča - 29 jún 2007 (see also P Sorensen & X Dong, PRC 74 (2006) 024902) 60

Vertex Detectors! l need less indirect measurement full reconstruction of charm decays! l l get rid of b/c ambiguities study relative abundances in charm sector l Silicon Pixels in ALICE (+ ATLAS, CMS) l Silicon Vertex upgrades in STAR, PHENIX Federico Antinori - Levoča - 29 jún 2007 61

Expected ALICE performance on D, B RAA colour charge dependence D 0 K - p + mass dependence B e+X mb = 4. 8 Ge. V 1 year at nominal luminosity (107 central Pb-Pb events, 109 pp events) Andrea Dainese (ALICE) Federico Antinori - Levoča - 29 jún 2007 62

Conclusions l Flavour in Quark Matter is going strong! l Extension to hard sector tantalizingly promising l Heavy flavour: we need more experimental information! two quantum jumps ahead: l l vertex detectors (ALICE, ATLAS, CBM, CMS, PHENIX, STAR) LHC l l l very high rates (expect ~ 100 cc, ~ 5 bb per central Pb-Pb!) truly hard probes + low x ! Federico Antinori - Levoča - 29 jún 2007 63

A big Ďakujem to the Organizers for an excellent SQM 2007 Conference (from every point of view) Federico Antinori - Levoča - 29 jún 2007 64