18/11/04DELPHI visits, PhC1 Visits to DELPHI/LHCb Ph.Charpentier

18/11/04DELPHI visits, PhC2 The travel and the arrival Parking Elevator Posters

18/11/04DELPHI visits, PhC3 Surface visit  Split into parties of up to 10 visitors  If needed, could be +1 (e.g. 45 visitors for 4 guides)  Warn the “gérants de site” when arriving for opening the sas  Maximum 2 groups in the cavern  Go to the lift with 2 groups immediately  The guides should use their access card, not the sas  Fill in the logbook next to the lift (name, number of visitors, time)  Make an introduction to the other groups showing them the surface posters (big-bang, LHC machine etc…)  For safety reasons, don’t let people into the construction hall  About 20 mn in the cavern, not more…  One group could go down once the first group is back  Split into parties of up to 10 visitors  If needed, could be +1 (e.g. 45 visitors for 4 guides)  Warn the “gérants de site” when arriving for opening the sas  Maximum 2 groups in the cavern  Go to the lift with 2 groups immediately  The guides should use their access card, not the sas  Fill in the logbook next to the lift (name, number of visitors, time)  Make an introduction to the other groups showing them the surface posters (big-bang, LHC machine etc…)  For safety reasons, don’t let people into the construction hall  About 20 mn in the cavern, not more…  One group could go down once the first group is back

18/11/04DELPHI visits, PhC4 A bit of history  Collaboration started in 1981  Founded by Ugo Amaldi (spokesperson until 1992)  Approved in 1983  : prototyping  : installation  : data taking  2001: dismantling  Ongoing: analysis and publications  LEP started on , stopped on  DELPHI is the only part of LEP detector remaining intact  In fact only the barrel is left, the endcaps have been dismounted  LHCb is the experiment on LHC at pit8  Under construction, hence not a visit area  Collaboration started in 1981  Founded by Ugo Amaldi (spokesperson until 1992)  Approved in 1983  : prototyping  : installation  : data taking  2001: dismantling  Ongoing: analysis and publications  LEP started on , stopped on  DELPHI is the only part of LEP detector remaining intact  In fact only the barrel is left, the endcaps have been dismounted  LHCb is the experiment on LHC at pit8  Under construction, hence not a visit area

18/11/04DELPHI visits, PhC5 DELPHI in numbers  Manpower: 500 physicists engineers / technicians  3 years of construction + installation  Weight: 3200 tons (2000 barrel + 2*600 endcaps)  Total length of cables: 1100 km  Many cables carry up to 16 electronics signals  3 level of electronics rooms on one side, 2 on the other  Electronics power: 500 kW  Data acquisition and control  75 microprocessors for signal treatment  15 powerful workstations on the surface for control  2 large mainframes for data collection  Data transfer on optical link or Intranet  - numbers - numbers  Manpower: 500 physicists engineers / technicians  3 years of construction + installation  Weight: 3200 tons (2000 barrel + 2*600 endcaps)  Total length of cables: 1100 km  Many cables carry up to 16 electronics signals  3 level of electronics rooms on one side, 2 on the other  Electronics power: 500 kW  Data acquisition and control  75 microprocessors for signal treatment  15 powerful workstations on the surface for control  2 large mainframes for data collection  Data transfer on optical link or Intranet  - numbers - numbers

18/11/04DELPHI visits, PhC6 The DELPHI detector

18/11/04DELPHI visits, PhC7 The detectors  Set of cylindrical detectors around the beam pipe  Beam pipe: beryllium and carbon fibre (11 cm in diameter)  e+e- collisions at the center  3 functions:  Locate the particles  Measure their momentum / energy  Identify their nature (electron, pion, proton, kaon, muon…)  From the center to the outer  Very precise at center  Less and less precise going to the outside  Tracking devices (4 layers: VD, ID, TPC, OT)  Identification device (RICH)  Solenoid  Electromagnetic calorimeter (lead absorber)  Hadronic calorimeter (iron absorber)  Muon detector  Set of cylindrical detectors around the beam pipe  Beam pipe: beryllium and carbon fibre (11 cm in diameter)  e+e- collisions at the center  3 functions:  Locate the particles  Measure their momentum / energy  Identify their nature (electron, pion, proton, kaon, muon…)  From the center to the outer  Very precise at center  Less and less precise going to the outside  Tracking devices (4 layers: VD, ID, TPC, OT)  Identification device (RICH)  Solenoid  Electromagnetic calorimeter (lead absorber)  Hadronic calorimeter (iron absorber)  Muon detector

18/11/04DELPHI visits, PhC8 Vertex Detector  Silicon ladders (precision 7µm) not yet presented

18/11/04DELPHI visits, PhC9 Inner Detector (ID)  Centre: “jet chamber”  Drift chamber made of 24 sectors of 24 wires each  Measure the time electrons take to go from the track to the wire  Outside: “straw tubes”  5 layers  Centre: “jet chamber”  Drift chamber made of 24 sectors of 24 wires each  Measure the time electrons take to go from the track to the wire  Outside: “straw tubes”  5 layers

18/11/04DELPHI visits, PhC10 Time Projection Chamber  Ionisation in a gas  Argon + methane  Electric field // axis  Electrons drift towards the outside  Located using a wire chamber with pads  Measure the drift time  V ~ 6.7 cm/µs  Get the distance  3 dimension device  Ionisation in a gas  Argon + methane  Electric field // axis  Electrons drift towards the outside  Located using a wire chamber with pads  Measure the drift time  V ~ 6.7 cm/µs  Get the distance  3 dimension device

18/11/04DELPHI visits, PhC11 Ring Imaging Cherenkov  Particles can go faster than light  In a given medium  Not in vacuum!  Effect similar to the sound barrier  Light shock-wave instead of sound shock-wave  Emission angle linked to the speed and the refraction index  Measuring the angle measures the speed  Light is focused by mirrors to form rings  Radius of ring depends on the angle  Particles can go faster than light  In a given medium  Not in vacuum!  Effect similar to the sound barrier  Light shock-wave instead of sound shock-wave  Emission angle linked to the speed and the refraction index  Measuring the angle measures the speed  Light is focused by mirrors to form rings  Radius of ring depends on the angle

18/11/04DELPHI visits, PhC12 Calorimeters  Stop particles in heavy material  Instrument it to “count” the number of particles created in the “shower”  Energy proportional to number of particles  Lead absorber: electrons and photons  HPC: detection based on the TPC technique  Iron absorber: hadrons (i.e. all others except muons and neutrinos)  HCAL: detection based on streamer tubes  Stop particles in heavy material  Instrument it to “count” the number of particles created in the “shower”  Energy proportional to number of particles  Lead absorber: electrons and photons  HPC: detection based on the TPC technique  Iron absorber: hadrons (i.e. all others except muons and neutrinos)  HCAL: detection based on streamer tubes

18/11/04DELPHI visits, PhC13 Solenoid  Superconducting solenoid  Cooled with liquid helium at 4.7 K  No power consumption  5000 Amperes  Magnetic field: 1.2 T  Largest superconducting solenoid in the world  Superconducting solenoid  Cooled with liquid helium at 4.7 K  No power consumption  5000 Amperes  Magnetic field: 1.2 T  Largest superconducting solenoid in the world

18/11/04DELPHI visits, PhC14 Useful infos   main DELPHI page   Detailed description for guides  All links therein pointing to specific detector descriptions  Phone numbers  Gerant de site: or  TSO: Bernard Corajod  Ph.Charpentier: or  R.Jacobsson: or   main DELPHI page   Detailed description for guides  All links therein pointing to specific detector descriptions  Phone numbers  Gerant de site: or  TSO: Bernard Corajod  Ph.Charpentier: or  R.Jacobsson: or