Gases for the COMPASS detectors (Run 2008)

Flammable gases in red. Please send corrections.

Gases for COMPASS Detectors (26 May 2008)
detector	modules	gases	mixture	volume (total)	typical flow	High Voltage	comments
			%	l	l/h	V
MicroMegas	12	Ne / C2H6 / CF4	80 /10 / 10	12	12	1000
DC Saclay	3	Ar / C2H6 / CF4	45 / 45 / 10	1300	15	1700
MWPC	14	Ar / CF4 / CO2	74 / 20 / 6	1955	140	4250	closed circuit
A	7			1225	70	2050
A*	1			190	10	2050
B	6			540	60	2050
W45	6	Ar / CF4 / CO2	85 / 10 / 5	8000	120	1925	closed circuit
GEMs	22	Ar / CO2	70 / 30	19	44	4000
PixelGEMs	5	Ar / CO2	70 / 30	4	12	4000
Straws	15 1)	Ar / CF4 / CO2	80 / 10 / 10	1500	750	1850	closed circuit
RichWall	1	Ar / CO2	70 / 30	3200	125	2050
MuonWall 1	2	Ar / CO2	70 / 30	3200	125	2050
MuonWall 2	6	Ar / CH4	75 / 25	1800	240	3000
RICH1 PD	8	CH4	100	320	300	2050	closed circuit
RICH1 rad	1	C4F10	100	800002)	normal: 5000 fast: 500003)	n.a.	closed circuit

¹⁾ double layers (1 module = 2 submodules = 2*3 double layers)
²⁾ just the vessel; total volume of the system, including filters and pipes is about 100000 l
³⁾ fast circulation system