Current Hall A Target Configuration

Standard Cryo-target with some modifications
 

The current Hall A target stack configuration is shown in the following table (Feb 12, 2002)
 

Target	Gas or material	Cell Length (or target thickness)	Radiator thickness (g/cm^2)*	Average  Front Window thickness**	Average  Back Window thickness**
Loop 1 Top Cell	He	4 cm	0	0.142 +/- 0.003 mm	0.150 +/- 0.003 mm
Loop 1 Bottom Cell	He	15 cm	0	0.124 +/- 0.003 mm	0.103 +/- 0.003 mm
Loop 2 Top Cell	He	15 cm	0	0.127 +/- 0.003 mm	0.127 +/- 0.003 mm
Loop 2 Bottom Cell	He	15 cm	0.8001 +/- 0.0005	0.114 +/- 0.003 mm	0.140 +/- 0.003 mm
Loop 3 Top Cell	H2	15 cm	0	0.127 +/- 0.003 mm	0.132 +/- 0.003 mm
Loop 3 Bottom Cell	H2	15 cm	0.8110 +/- 0.0005	0.130 +/- 0.003 mm	0.140 +/- 0.003 mm
Optics tgt	C (pyrolitic graphite)	See Below	0	NA	NA
15 cm Dummy	Al 6061-T6	15 cm	0	0.26994 +/- 0.0005 g/cm^2	0.27146 +/- 0.0005 g/cm^2
4 cm Dummy	Al 6061-T6	4 cm	0	0.27035 +/- 0.0005 g/cm^2	0.27173 +/- 0.0005 g/cm^2
Blank	NA	NA	NA	NA	NA
BeO Viewer	BeO (99.99% pure)	0.3692 g/cm^2	0	NA	NA
Empty	NA	NA	NA	NA	NA

*The radiator material is 99.996% (Cu63 69.09%)+(Cu65 30.91%)
** the cell material is Al 7075 T6 for each of the loops and Al 6061 T6 for the dummy targets

Optics Target Foil Thicknesses (foil 1 is most upstream foil, foil 9 is most downstream foil)

1) 50.94 +/- 0.7 mg/cm^2
2) 51.19
3) 51.59
4) 50.72
5) 49.38
6) 50.22
7) 51.59
8) 53.08
9) 49.03