Post-Service Icemonitor Data (2013 Sep 10)

The Warm and pump service was successful in removing the dewar ice from NIRSPEC.

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Post-Service Icemonitor Data (2010 Nov 03)

The Warm and pump service was successful in removing the dewar ice from NIRSPEC.

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Post-Service Icemonitor Data (2010 Oct 14)

The Warm and pump service was successful in removing the dewar ice from NIRSPEC.

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Routine Icemonitor Data (2010 Sept 13)

Eleven months after the last NIRSPEC service and we see signs of ice absorption. A warm and pump service is scheduled for September 19 through October 14.

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Routine Icemonitor Data (2010 May 07)

Seven months after service and we are starting to see signs of ice absorption. The "Serv+3 mon" curve (2009dec22) of this iteration looks the same as the "Serv+7 mon" curve (2009apr28) from the previous iteration. We will try to schedule a service during 2010B.

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Routine Icemonitor Data (2009 December 22)

Three months after the service, the dewar window still looks clean. The current curve is purple. In the divided flat, the current curve is lowest, but within the scatter of new or post-service windows. In the divided flat, the current curve is at 0.9 versus the post-service values of 1.1--although I don't know what a value greater than 1 means.

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Post-Service Icemonitor data (2009 September 29)

After the recent NIRSPEC service, there is no sign of dewar ice absorption. The green curve is current.

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Routine Icemonitor data (2009 August 06)

It's been 10 months since the NIRSPEC service. The water ice absorption is approaching 10-20%. We hope to service NIRSPEC in September which should clear this up. 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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