First Physics at the LHC ALICE Bjørn S. Nilsen Creighton University

January Creighton University, Physics2 CERN and the LHC 9/29/1954 CERN born 11/24/1959 PS Starts 1976 SPS Starts July 1989 LEP starts 12/13/1990 ALICE starts 1993 ALICE proposed 11/2/2000 LEP ends 3/27/2007 Small Exposition Inner Triplet damaged 9/19/2008 Big Exposition 53 magnets damaged 11/23/2009 LHC’s First Collisions ALICE LHCb CMS ATLAS Genevé

January Creighton University, Physics3 LHC Experiments ATLAS Higgs Search New Particle Search Peripheral Heavy Ion program –LHCf CMS Higgs Search New Particle Search Heavy Ion Physics –Jets –Heavy resonances –TOTEM ALICE –Comprehensive Heavy Ion program –Complementary p+p program LHCb –B factory

January Creighton University, Physics4 A Large Ion Collider Experiment PHOS, cpv Muon, MTRG VHMPID JCal T0 PMD V0 FMD ZDC ACORDE HMPID TRD TOF TPC ITS, SPD, SDD, SSD EMCAL

January Creighton University, Physics5 First Cosmic seen in ALICE TPC April

January Creighton University, Physics6 First Beam Gas Events in ITS 6/4/2008

January Creighton University, Physics7 During down time Removed and reinstalled Mini-space frame Cabling nightmare, Please don’t do it again Installed 4 EMCal Super Modules Repaired TPC and other detectors Fixed and many sundries things Significant improvements in software, Online, Offline, and Grid

January Creighton University, Physics8 First beam in LHC September Signals as seen in ALICE’s V0A (blue) and V0C (red) Detectors Machine group has placed, up stream of ALICE, a small Wire Chamber which the beam interacts with producing a particle shower seen by ALICE.

January Creighton University, Physics9 Particle Physics in a Nutshell Atoms –Electrons –Nucleus (Quarks + gluons) Protons (u  u  d) Neutrons (d  d  u) Leptons e ±,  ±,  ± Quarks u c t 2/3 e d s b -1/3 e Force partials , W ±, Z 0, g, graviton Higgs (Weak symmetry breaking) h

January Creighton University, Physics10 Kinematics in a nut shell  pzpz Mandelstam Variables ?

Flow Equation of State Physical Review C, Volume 68, (2003) How pressure gradients effect the QGP fluid.

January Creighton University, Physics12 Jet Suppression at STAR Elena Bruna, for the STAR Collaboration Yale University, presentation at Winter Workshop on Nuclear Dynamics, Ocho Rios, Jamaica January 2 - 9, 2010 QGP Jet How fast moving colored objects behave in a strong force dominated medium

First ALICE p-p Event √s=900 GeV

January Creighton University, Physics14 ALICE V0 Timing V0-A side V0-C side from interaction region from beam line from interaction region from beam line V0-A V0-C

January Creighton University, Physics15 Calculated in Offline from tracklets in Silicon Pixel Detector:  x ~ 475 µm  y ~ 475 µm  z ~ 4.2 cm

First Publication This is the first (and easiest) of many numbers we need to (re)measure to get confidence in our detectors, tune the simulations, study background,.... Phase 2 is still a long way to go.. last time measured at the ISR for pp The average number of charged particles created perpendicular to the beam in pp collisions at 900 GeV is: dN/d  = 3.10 ± 0.13 (stat) ± 0.22 (syst)

Muon Spectrometer ITS On 6 th December, ‘stable beams’ were declared & we could switch on all ALICE detectors for the first time.. TPC, TRD, TOF, HMPID First Full ALICE Event

Particle ID by dE/dx TPC No vertex cut ! ITS Preliminary

January Creighton University, Physics19 Particle ID working within each detector 15/2/2006 LHCC Status Report J. Schukraft TRD Electrons Pions velocity v/c TOF Protons Kaons Pions all plots: preliminary calibration & alignment ! Preliminary

January Creighton University, Physics20 PHOS Finds  0    1 < p t < 1.5 GeV PHOS (9 m 2 ) Noise 00 Preliminary

January Creighton University, Physics21 Track reconstruction in TPC TPC Rods SSD TPC Vessel 1 TPC Vessel 2 SDD SPD  -ray image of ALICE photon conversion vertices Preliminary

January Creighton University, Physics22  0 using TPC    e + e - e + e - m  0 = MeV Preliminary

PDG: MeV  p PDG: MeV  p Finding the Zoo of Particles  p  Preliminary

January Creighton University, Physics24 Still more PDG: MeV K 0 s      PDG: MeV Preliminary

January Creighton University, Physics25 Once particles are identified p/p ratio to study Baryon Transport via di-quark stopping or gluon junctions And Many other Ratios Preliminary

January Creighton University, Physics26 Including more complicated measures  - HBT correlation function to study space-time evolution (also reference for heavy ion data) Data Monte Carlo (no HBT correlations) Preliminary

January Creighton University, Physics27 Conclusion Finally after many years, data is coming –At injection energy, 900 GeV –At LHC’s first acceleration to 2.36 GeV Things are working better then expected There still is a lot of work to go Many exciting results are anticipated A number of unexpected things will happen A number of unexpected results will surprise us all.

Upcoming Schedule 2010, Start running p-p at 7 TeV cm. End of 2010, First Pb-Pb run at 2.75 TeV/n cm. 2011, full p-p run at 7 TeV cm. End of 2011, additional Pb-Pb run at 2.75 TeV/n cm. After 2011, long shutdown to finish repairs and get machine working at 14 TeV p-p cm.