Table 4. Absorber filters in the OH attenuator.

d is the filter thickness in mm.

Arm 1 (upstream)			Arm 2			Arm 3			Arm 4 (downstream)
Slot	Type	d	Slot	Type	d	Slot	Type	d	Slot	Type	d
1	Empty		1	Empty		1	Empty		1	Empty
2	CVD	0.8	2	CVD	0.4	2	CVD	0.2	2	CVD	0.1
3	CVD	3.2	3	CVD	1.6	3	CVD	0.8	3	CVD	0.4
4	Si	6.4	4	Si	3.2	4	Si	1.6	4	Si	0.2
5	Si	1.6	5	Si	0.4	5	Si	0.4	5	Ge	0.5
6	Si	0.8	6	Si	0.8	6	Si	0.2	6	Si	0.8
7	Si	0.2	7	Si	0.1	7	Si	0.05	7	Si	0.025