18/11/04 DELPHI visits, PhC 1
Visits to DELPHI/LHCbVisits to DELPHI/LHCb
Ph.CharpentierPh.Charpentier
18/11/04 DELPHI visits, PhC 2
The travel and the arrivalThe travel and the arrival
Parking
Elevator
Posters
18/11/04 DELPHI visits, PhC 3
Surface visitSurface 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
18/11/04 DELPHI visits, PhC 4
A bit of historyA bit of history
Collaboration started in 1981 Founded by Ugo Amaldi (spokesperson until 1992) Approved in 1983 1982-1985: prototyping 1986-1988: installation 1989-2000: data taking 2001: dismantling Ongoing: analysis and publications
LEP started on 14.07.1989, stopped on 2.11.2000 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 1982-1985: prototyping 1986-1988: installation 1989-2000: data taking 2001: dismantling Ongoing: analysis and publications
LEP started on 14.07.1989, stopped on 2.11.2000 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
18/11/04 DELPHI visits, PhC 5
DELPHI in numbersDELPHI in numbers Manpower: 500 physicists + 500 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 http://delphi-expo.web.cern.ch/DELPHI-Expo/VisitingDELPHI.html - numbers
Manpower: 500 physicists + 500 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 http://delphi-expo.web.cern.ch/DELPHI-Expo/VisitingDELPHI.html - numbers
18/11/04 DELPHI visits, PhC 6
The DELPHI detectorThe DELPHI detector
18/11/04 DELPHI visits, PhC 7
The detectorsThe 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
18/11/04 DELPHI visits, PhC 8
Vertex DetectorVertex Detector Silicon ladders (precision 7µm) not yet presented Silicon ladders (precision 7µm) not yet presented
18/11/04 DELPHI visits, PhC 9
Inner Detector (ID)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
18/11/04 DELPHI visits, PhC 10
Time Projection ChamberTime Projection Chamber
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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
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sont requis pour visionner cette image.
18/11/04 DELPHI visits, PhC 11
Ring Imaging CherenkovRing 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
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sont requis pour visionner cette image.
18/11/04 DELPHI visits, PhC 12
CalorimetersCalorimeters 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
18/11/04 DELPHI visits, PhC 13
SolenoidSolenoid 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
QuickTime™ et undécompresseur TIFF (non compressé)
sont requis pour visionner cette image.
18/11/04 DELPHI visits, PhC 14
Useful infosUseful infos
http://delphiwww.cern.ch/ main DELPHI page
http://delphi-expo.web.cern.ch/DELPHI-Expo/VisitingDELPHI.html Detailed description for guides All links therein pointing to specific detector descriptions
Phone numbers Gerant de site: 77801 or 160378 TSO: Bernard Corajod 163350 Ph.Charpentier: 74244 or 160167 R.Jacobsson: 73619 or 163730
http://delphiwww.cern.ch/ main DELPHI page
http://delphi-expo.web.cern.ch/DELPHI-Expo/VisitingDELPHI.html Detailed description for guides All links therein pointing to specific detector descriptions
Phone numbers Gerant de site: 77801 or 160378 TSO: Bernard Corajod 163350 Ph.Charpentier: 74244 or 160167 R.Jacobsson: 73619 or 163730