Úvod – celoústavný seminár ÚEF, L. Šándor 1 ÚEF SAV a ALICE A L ARGE I ON C OLLIDER E XPERIMENT FOR THE LHC - CERN L ARGE H ADRON C OLLIDER Ladislav Šándor Oddelenie subjadrovej fyziky Ústav experimentálnej fyziky SAV

Úvod – celoústavný seminár ÚEF, L. Šándor 2 Why heavy ions at high energies ? QCD prediction on a new state of matter (QGP) formation at high enough energy density Experiments at the CERN SPS (√s NN = 17 GeV) – observation of new collective effects (anomalous J/  suppression, strangeness enhancements, dilepton spectra anomalies) Experiments at the RHIC in BNL - (√s NN = 200 GeV) confirm SPS results and reveal the presence of other QGP signatures too Next natural step to higher energy (√s NN = 5.5 TeV) – building of the dedicated ion experiment for the new CERN accelerating complex LHC project ALICE

Úvod – celoústavný seminár ÚEF, L. Šándor 3 Why Slovakia in ALICE ? Active work of Slovak physicists (both experimentalists and theorists) in heavy-ion physics for about two decades Fruitful experience from a number of SPS experiments (NA34-Helios, WA97, NA49, NA57) Unique potential of ALICE – the only dedicated heavy-ion experiment at LHC – for A-A, p-A and also p-p physics attracting interest of qualified teams from Bratislava and Košice to continue working in heavy-ion physics

Úvod – celoústavný seminár ÚEF, L. Šándor 4 Large Hadron Collider aéroport Genève 3.8 m diameter circular tunnel circumference of ring – 27 km buried 50 to 175 m underground Aerial view with location of experiments

Úvod – celoústavný seminár ÚEF, L. Šándor 5 LHC experiments Slovak participation Energy of protons – up to 7 TeV per beam. Available energy in p-p reaction is √s = 14 TeV ( 7 x higher wrt Tevatron). For lead ion (Pb-Pb) collisions energy for pair of nucleons is √s NN = 5.5 TeV ( ~30 x higher wrt RHIC) Start of LHC operation : late 2009 (data collection for physics at 5 TeV per proton beam starting end of October) Colliding of two counter rotating proton or heavy-ion beams

Úvod – celoústavný seminár ÚEF, L. Šándor 6 ALICE design philosophy General Purpose Heavy Ion Detector only one dedicated heavy-ion experiment at LHC (ATLAS/CMS will contribute, but their priority is pp physics) AGS/SPS : several (6-8) special purpose experiments RHIC : 2 large multipurpose, 2 smaller special purpose expts cover essentially all known observables comprehensive study of hadrons at midrapidity (large acceptance, excellent tracking and particle identification (PID) state-of-art measurement of direct photons (excellent resolution & granularity EM calorimeter) dedicated & complementary systems for di-electrons and di-muons cover the full spectrum from soft (10’s MeV) to hard (100’s GeV) stay open for changes & surprises

Úvod – celoústavný seminár ÚEF, L. Šándor 7 ALICE experiment Main physics goals: ultrarelativistic nucleus- nucleus collisions in extreme conditions (high pressure and energy density) physics of the QCD vacuum detailed investigation of new state of matter – the Quark-Gluon Plasma general characteristics of p-p interactions in a new energy domain Difficult experimenting with high demands on computing Total cost: ~150 MCHF Slovak contribution: 0.8 MCHF Details on ALICE :

Úvod – celoústavný seminár ÚEF, L. Šándor 8 What are we going to cope with Expected multiplicity in central Pb-Pb: dN ch /d  ~ 1500 – 6000 in Pb-Pb collisions at LHC ?

Úvod – celoústavný seminár ÚEF, L. Šándor 9 > 1000 members 90 institutions 30 countries ~ 25 Slovak physicists and engineers ALICE collaboration Participating institutes: - Comenius University Bratislava, team leader : B. Sitár contribution to the TPC detector (read-out chambers) and to the DCS – the detector control system - Institute of Exp. Physics SAS, P.J. Šafárik University Košice, team leader : L. Šándor router electronics for the SPD (Silicon Pixel Detector) and contribution to the CTP - the central trigger system, radiation studies

Úvod – celoústavný seminár ÚEF, L. Šándor 10 Inner Tracking System (ITS) R out =43.6 cm L out =97.6 cm SPD SSD SDD 6 layers, three technologies, material budget < 1% X o per layer (0.2 m2, 9.8 Mchannels) SPD – silicon pixel detector (0.2 m2, 9.8 Mchannels) SDD – silicon drift detector (1.3 m2, 133 kchannels) SSD – silicon strip detector (4.9 m2, 2.6 Mchannels) Silicon Pixel Detector Two SPD layers at r = 3.9 & 7.6 cm Structured to 60 staves containing 9.8 M active pixel channels

Úvod – celoústavný seminár ÚEF, L. Šándor 11 SPD readout architecture DC S Trigge r DAQ JTAG, CLK, Detector Data ~100m PCI-MXI-II-VME VME Router C(ard one router services 6 halfstaves SPD contains 20 router boards Košice commitment (J. Bán, M. Krivda) Cost : 6 MSK (240 kCHF)

Úvod – celoústavný seminár ÚEF, L. Šándor 12 Some important dates... approval of LHC approval of ALICE experiment preliminary agreement on the router electronics development in Kosice.... spring 1999 workshop on ALICE SPD electronics in Kosice, about 20 participants from CERN, Birmingham, Budapest, Italian laboratories, presentation of the SPD router project (J. Bán) Nov 1999 green light for the router electronics router production finished august 2006 installation and integration of routers in ALICE experimental area … summer-autumn 2007

Úvod – celoústavný seminár ÚEF, L. Šándor 13 Inštalácia SPD

Úvod – celoústavný seminár ÚEF, L. Šándor 14

Úvod – celoústavný seminár ÚEF, L. Šándor 15 ITS s vákuovou trubicou

Úvod – celoústavný seminár ÚEF, L. Šándor 16 T D Lee, May 2004

Úvod – celoústavný seminár ÚEF, L. Šándor 17 T D Lee, May 2004

Úvod – celoústavný seminár ÚEF, L. Šándor 18 SQM 2008 中国 · 北京 · 清华大学 2008 年 10 月 安飞德 意大利国家核物理学院（帕多瓦）18