NIRSPEC Monitoring of Ice on Window

NIRSPEC
Monitoring of Ice on the Entrance Window

Routine Icemonitor data (2008 November 13)

It's been 2 months since the NIRSPEC service. There does not appear to be significant water ice absorption. The current curve is purple.

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Routine icemonitor data (2008 July 24)

15 months have passed since the NIRSPEC service. NIRSPEC will be taken offline for a warm and pump service between August 14 and September 9. We are looking to stay ahead of the ice.

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Post-service Icemonitor data (2007 Mar 29)

NIRSPEC was be taken offline March 7-28 to warm the dewar and pump. This service will test whether simply warming and pumping removes ice from the dewar window, or whether the window needs to be replaced.

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Earthquake Power Outage did not cause significant ice buildup (2006 Nov 01)

The NIRSPEC entrance window was replaced at the end of March 2006. No icemonitor data were taken until after the earthquake-induced power outage on 15 October 2006. In post-quake icemonitor data, the ice absorption looks similar to the 6 month absorption from the previous window. Compare to 2005 Aug 19 below.

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