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Stony Brook Update:Keep It Clean

T.K. Hemmick for the Tent Crew

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Cleaning Complete Almost Complete• Excellent progress made on cleaning both the HBD

itself and the glovebox.• Clean Air Bath(s)

– Laminar table provided clean air bath for the HBD itself resting there for about one week.

– Dust levels unmeasurable holding dust monitor at the surface under air flow.

– Glovebox proved to be more of a challenge.– Dust does not want to leave closed quarters.– Large (2’ x 4’) high flow HEPA unit on removed wall at

airlock end…open wall at HBD end.– Excellent readings after a few days (class 20).– HOWEVER(!) HEPA filter on inlet side of the glovebox is

somehow shot (source of dust, even though air entering filter is clean)

– New filters on order…no shot until glovebox closed & clean.

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Ultrasound cleaning not yet successful.• Ultrasound was used on a HIGHLY damaged Au

GEM:– 40o, 18 M-cm water.– 20 minutes each at four frequencies:

• 40 kHz, 70 kHz, 140 kHz, 170 kHz– Dried in 10-6 torr vacuum overnight.

• Positive effects, but not good enough.– GEM was among the most highly damaged in the HBD.– Measured non-linear current draw & confused the

capacitance meter (250 nF !!).– After cleaning, the GEM looks beautiful.– Measures normal capacitance.– Draws non-linear current.

• Further tests will be made on less severely damaged GEMs.

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Expected Schedule

• Glove box is immaculate except for bad inlet HEPA filter.

• Tent sparkles as well.• HBD vessel is ready.• GEMs are waiting in evaporator for the shot.• Shot can happen the day after the filter

arrives (probably Thursday or Friday).• BIG QUESTION:

Do we need to install shades shades componentsbefore closing up the glovebox?