108 Mar 2007 L. Musa
TPC CommissioningALICE Technical Forum, CERN, 8th March 2007
L. Musa
Outline
• Pre-commissioning above ground (2006)
• Preparing for the commissioning in the cavern (2007)
208 Mar 2007 L. Musa
A first phase of TPC Commissioning was carried out above ground in the course of 2006
• Jan-Mar installation of SSW and FEE
• April start of gas system
• May HV (100KV) applied to FC
• Jun–Dec test of all sectors (in pairs)
Each sector was operated continuously over a period of 40 hours and verified with
• calibration pulser, • cosmic-muon trigger detector ACORDE • UV laser system for the generation of tracks in the detector
Many TPC and ALICE sub-systems (e.g. cooling, gating grid pulser, temperature sensors, DCS, Trigger, DAQ, HLT and Offline) have been part of this commissioning programme
TPC pre-commissioning above ground (2006)
~300 man shift, 3588 runs, ~24 TB in CASTOR
308 Mar 2007 L. Musa
Only two sectors can be instrumented at a time with – Low Voltage Power Supplies– Cooling
Commissioning objectives– Test functionality of all components – gas stability, noise, signal tails, gain homogeneity, space
resolution, etc.
Cosmic tests
Laser testsALICE COSMIC Trigger (ACORDE)
Each pair of sectors continuously operated over 40 hours
TPC pre-commissioning above ground (2006)
408 Mar 2007 L. Musa
TPC pre-commissioning (2006); some results – Noise measurements
r.m.s. of the pedestals (sNOISE) is below 1 ADC count
as required in the Technical Design Report
(PASAnoise2 + ADCnoise
2) = 0.70 ADC counts
508 Mar 2007 L. Musa
space point resolution as function of z position (cut on inclination angle tan(f) <0.05)
TDR value: 210m / cm
A
A
Q total (total charge in the cluster) as function of z position
relative decrease over the full TPC length: ~7% decrease due to electron capture and threshold effect
TDR value 1% / m per ppm of O2
3 ppm of O2 measured with gas chromatograph
B
B
TPC pre-commissioning (2006); some results – Cosmic tracks
608 Mar 2007 L. Musa
DesignDesign MeasuredMeasured
TPC pre-commissioning (2006); some results – Laser tracks
Drift velocity = 2.73 cm/m agreement with drift monitor detector (Goofie)
708 Mar 2007 L. Musa
Moving the TPC into the ALICE magnet
Jan ‘07 TPC has been lowered in UX25
After the alignment with respect to the beam line, the TPC has been put in parking position.
Feruary, alignment of SSW with respect to endplate, and test of the connection of FEE to the endplate (calibration pulser)
All 4356 FECs and 216 RCUs are working
All 26136 kapton cables are properly connected to the pad plane
808 Mar 2007 L. Musa
Alignment of SSW wrt endplate within mmR
eado
ut C
ham
ber
~7 mm
X
Z
Y
Displacements of SSW wrt endplate should not exceed 3mm
Fro
nt
En
d C
ard
kapton cable
908 Mar 2007 L. Musa
Preparing for Commissioning in UX25
Still some hardware components to be finalized and/or constructed. Two examples:
• Trigger Busy Box (being finalized and tested)
• Trigger&DCS Interface Unit for Laser, GG Pulser and
Calibration Pulser (starting design)
Many software components to be finalized and commissioned Some examples:
• Software for the configuration and monitoring of the
FEE
• Interface to the FERO database
• Interface to ECS
• DCS for some of the sub-systems and TPC FSM
(Supervisory Layer)
• Data Quality Monitoring
In 2006 all efforts mostly devoted to pre-commissioning in SXL2
1008 Mar 2007 L. Musa
Cables and cooling pipes (before connecting to the TPC all cables and cooling lines will be tested)
cables from crates to backframe (C side): April
test of cables @ backframe (C side): May
Connection of TPC C side June
TPC wil be moved to final position (interaction point) and connected to the gas system in June
(~about 1 month before reaching nominal conditions)
Preparing for Commissioning in UX25
Connection of TPC A side Aug
1108 Mar 2007 L. Musa
TPC commissioning - Milestones
Test of FEE & ROC (C-side)
Test of FEE, Trigger, DAQ, DCS and all servicesJuly Test of ROCs July -
Aug Test of FEE & ROC (A-side)
Test of FEE, Trigger, DAQ, DCS and all serviceSep
Turn on FEE July
Turn on FEE Sep
TPC Commissioning with cosmic tracks, laser Sep - Oct and Kr (under study)
ALICE Commissioning Oct -Nov
