TPC-Meeting : Københaven 2.9.02

• Ne-CO2 Gas System : Status

• CO2 - Gas System : Insulating Gap • Resistor Rod :

– Contacts– Cooling --> Liquid– Cooling --> Gas

Ne-CO2 - Gas System :

• Mixing Unit ok• Compressor Rack ok• Cleaning Cartridges ok• Pressure Tank ok• CO2 - Remover prep

• Hardware ready --> Jan 2003

• Slow control --> mid 2003

Ne-CO2 - Gas Quality Controls

• CO2 - Monitor (0.1%) --> permanent

• 2(O2 & H2O) -Monitor’s --> permanent

• 2 Goofie - Drift-Monitors --> permanent– Drift vel : < 1 %o – Gas (in & out; mounting: near TPC-vessel)

• Gas Chromatograph --> if needed– N2; impurities(CHn; SF6 ; ect.);

CO2 - Insulation Gap Gas System

• CO2 - Recovery :– Closed System– Design Meeting --> Alice week:

sept.02

TPC_Resistor Rod

• Promised :– Weight Watching & Contacts :

• *1/4 & 100 cm Model

– Cooling Tests :• 100 cm Model

– HV & Security Tests :• 200 cm Model

Contacts

Water flow

Alternating Gradient

Cooling

20.25 Co20.20 Co20.1 Co20.05 Co20.0 Co19.75 Co19.8 Co19.9 Co19.95 Co20.0 CoAlternating Gradient

Cooling

Cooling Efficiency :--> Cooling Efficiency :-->

T.M --> BTC !T.M --> BTC !

Rod - Cooling Systems• Leakless Water Cooling

– Control System : like FEC’s– 10 mm Pipes – Cost : 25 kSFR

• CO2 - Gas Cooling– 60 mm Pipes & 50 m– Leaks into Ne_CO2 Volume ???– Cost : (30 components + 30 labor (?) + – 20 heat exchanger ) --> 80 kSFR (?)

Rod-HV- Tests

• 300 kV HI-Injector @ GSI

• 30 Years of HV-Operation

• With :

•Distilled Water-Resistor Chain

300 kV GSI Ion Source : • Uses since 30 years :• Destilled Water Channel as 300kV Divider

– Interlock : Water Quality• < 2 µ Siemens / cm

Resistor Rod HV test : – Rod-Cooling Water Channel --> – Connected to HV with Copper-Return Bridge

• Additonal parallel resistor : --> f(water quality)

Are’s test setup:

HV-Test @ GSI HI - source

• Rod in Nitrogen Atmosphere• Rod filled with :

– Nitrogen– Distilled Water ( < 0.1 & <1 µ Siemens)– Circulation Pump OFF– Tap - Water

• ∂V_last Resistor • & Total Rod Current

Conclusions : I• Removable Resistor Rod :

– Possible --> go_to --> 250 cm

• AGC --> – very efficient -> results soon– Price & Space

• Liquid Cooled Rod : internally save :– HV & Leak – Ceramic Bridge --> Security Factor: * 1015

– Rod Resistivity = f (water quality) --> adjust !

Conclusions : II

• Remaining Heat Sources in TPC

– G_Ohm Resistor Chain -> up to 4 Watt

Let’s Cool them !!!

4W - Distilled Water Resistor Chain

• Adjust Water Quality : • --> (0.05 and 2) µ_Siemens• ( 18 --> 0.5 ) M_Ohm / cm

•TPC Gas Heat Problem goneTPC Gas Heat Problem gone ! !