Spares SQM08@Beijing Giuseppe E. Bruno

low-x (a field of its own!) large cross-sections low-x (a field of its own!)  accessible x1, x2 regions in the ALICE experiment muon arm muon arm central detector central detector SQM08@Beijing Giuseppe E. Bruno

Collisions… Proton + detector collision 11.09. run 58338 ev 27 SQM08@Beijing Giuseppe E. Bruno

Perspectives for D± elliptic flow GOAL: Evaluate the statistical error bars for measurements of v2 for D± mesons reconstructed from their Kpp decay in Pb-Pb collisions v2 vs. centrality (b=collision impact parameter) v2 vs. pT in different centrality bins HOW: fast simulation to generate: ND+ (DpT,Db) with an angular distribution dND/dj = v2D,in cos [2(j-YRP)] For each D+: an event made of Ntracks is superimposed dN/dj = v2ev,in cos [2(j-YRP)] Inputs of the simulation: ND+ (DpT,Db) , v2D,in, Ntracks ,v2ev,in Outputs: v2D measured. SQM08@Beijing Giuseppe E. Bruno

v2 vs. pT How to increase the statistics? Sum D0→Kp and D±→Kpp Semi-peripheral trigger Sum D0→Kp and D±→Kpp Sufficient for v2 vs. centrality v2 vs. pT that would be obtained from 2·107 semi-peripheral events (e.g. 6<b<9 fm) How to increase the statistics? Large stat. errors on v2 of D± → Kpp in 2·107 MB events 6<b<9 fm MB trigger SQM08@Beijing Giuseppe E. Bruno

Experience at colliders: CDF √sNN=1960 GeV Since the B hadrons with as little as zero momenta produce J/y with momenta as large as 2 GeV/c, the measured cross section for pt(J/y)>1.25 GeV/c is sensitive to the complete pt(B) spectrum Ref: D. Acosta et al Phys. Rev. D 71, 032001 (2005) SQM08@Beijing Giuseppe E. Bruno

Performance plot w.r.t. CDF tot tot J/y J/y from B bkg ALICE CDF 2<pT<3 Gev pT>5 Gev 3<pT<5 Gev pT>0 1 mb event SQM08@Beijing Giuseppe E. Bruno 7

Statistical Significance Partial TRD installed (4 out of 18 super mod.) Full TRD All pairs One track in Both in tot J/y bkg S=34±6 S=14±3 S=15±5 S=5±2 SQM08@Beijing Giuseppe E. Bruno

Beauty in the barrel: displaced J/ye-e+ tot J/y bkg pT>5 Gev 102 10 1 Entries/100mm -2000 -1000 1000 2000 3000 x [mm] tot J/y J/y from B bkg sum prompt J/y x 2<pT<3 Gev 102 10 1 Entries/100mm -2000 -1000 1000 2000 3000 x [mm] tot J/y J/y from B bkg sum prompt J/y x 109 pp events Analysis based on a simultaneous fit of the invariant mass spectrum an “impact parameter” to separate prompt from detached J/y, e.g. pseudo- proper decay time (CDF) D.Acosta et al Phys. Rev. D 71 (2005) 032001 This measurements can allow a determination of the dsbb/dpt cross-section down to pt≈0 Events/10 MeV 109 pp events 350 300 250 200 150 100 50 2.8 2.9 3.0 3.1 3.2 m(e+,e-) [GeV] tot J/y bkg SQM08@Beijing Giuseppe E. Bruno

ALICE performance: Vertexing 3D reconstruction from tracks of primary (interaction) and secondary (decay) vertices position with full error-matrix treatment Resolution on vertex position important for Impact parameter resolution (in pp low multiplicity events) Separation of secondary vertices from the primary Determination of the pointing angle Primary vertex in pp Decay vertex D+  K-p+p+ SQM08@Beijing Giuseppe E. Bruno

Physics at LHC - Philippe Pillot Quarkonia in dimuon pp, √s=14 TeV 1 month central Pb-Pb (0 < b < 3 fm) Luminosity of 51026 cm-2s-1 Shadowing + PTμ > 1 GeV/c Statistics in the interval M ± 2 σ State S[103] B[103] S/B S/(S+B)1/2 J/Y 130 680 0.20 150 Y’ 3.7 300 0.01 6.7 (1S) 1.3 0.8 1.7 29 (2S) 0.35 0.54 0.65 12 (3S) 0.42 0.48 8.1 J/Ψ mass resolution ~ 70 MeV/c2 Υ mass resolution ~ 100 MeV/c2 No clear signal for Ψ’ and Υ(3S) (J. Phys. G 32 (2006) 1295) 03/10/08 SQM08@Beijing Physics at LHC - Philippe Pillot Giuseppe E. Bruno 11

PbPb cent, 0 fm<b<3 fm Quarkonia to dimuons 1 month Pb-Pb PbPb cent, 0 fm<b<3 fm State S[103] B[103] S/B S/(S+B)1/2 J/Y 130 680 0.20 150 Y’ 3.7 300 0.01 6.7 (1S) 1.3 0.8 1.7 29 (2S) 0.35 0.54 0.65 12 (3S) 0.42 0.48 8.1 Expected yields J/y high statistics: 0-20 GeV/c y’ poor significance (1S) & (2S) : 0-8 GeV/c (3S) ok, but 2-3 runs needed SQM08@Beijing Giuseppe E. Bruno

Physics at LHC - Philippe Pillot Quarkonia to dielectrons 1 month central Pb-Pb (10%) Luminosity of 51026 cm-2s-1 Shadowing + pTe > 1 GeV Statistics in the interval M ± 1.5 σ State S[103] B[103] S/B S/(S+B)1/2 J/Ψ 120 100 1.2 245 (1S) 0.9 0.8 1.1 21 (2S) 0.25 0.7 0.35 8 J/Ψ mass resolution ~ 30 MeV/c2 Υ mass resolution ~ 90 MeV/c2 Ψ’ and Υ(3S) quite difficult 03/10/08 SQM08@Beijing Physics at LHC - Philippe Pillot Giuseppe E. Bruno 13

HF to single muon in p-p Signal:  from b/c decays Background:  from /K decays Can be extracted from data  from the absorber Subtraction: tracks do not point to the vertex, no FMD hits Good preliminary results: high statistics needed Slices in pT. Correct for diamond shape SQM08@Beijing Giuseppe E. Bruno

B signal from dimuons w/o vertexing unlike-sign total unlike-sign from bottom unlike-sign from charm like-sign from bottom unfold mass continuum large statistics is expected systematics to be estimated central PbPb (5%), one month Mass (GeV/c2) 0-5 5-20 N from bb 41461793 6983130 (J. Phys. G 32 (2006) 1295 | Ph. Crochet @ ALICE workshop Sibiu 2008) 03/10/08 03/10/08 Physics at LHC - Philippe Pillot Physics at LHC - Philippe Pillot 15

HF to muons BDsame B µ+ + D + X µ- + X BBdiff B µ- + X X + µ+ Single muons from beauty are dominant at high pT  fit on distribution tail Muons from charms are dominant at low pT  difficult measurement due to large background Muon pairs from B: BDsame B µ+ + D + X µ- + X BBdiff BDsame BBdiff B µ- + X X + µ+ SQM08@Beijing Giuseppe E. Bruno

Physics at LHC - Philippe Pillot Quarkonia acceptance Dielectron channel Dimuon channel J/ J/ Dielectron trigger: pTe > 3 GeV/c   Dimuon trigger: pTμ > 1 (2) GeV/c for J/ () 03/10/08 SQM08@Beijing Physics at LHC - Philippe Pillot Giuseppe E. Bruno 17

Large suppression at RHIC! n.p. electrons ~ as suppressed as expected for c only (no b) yet, region above 3-4 GeV expected to be dominated by beauty... non phot. el. scaled to M. Cacciari et al., hep-ph/0502203 [J.Bielcik @QM05] [Xin Dong@QM05] disentangling c/b is a must! e.g. full reconstruction of D vertices SQM08@Beijing Giuseppe E. Bruno