GeminiFocus
by Joe Jensen and Gustavo Arriagada
GNIRS Recovery Update Figure 1.
GNIRS optical bench assembly is moved into the clean-room at the Gemini North Base Facility in October, 2007.
A
t the end of April, just as the June 2007 issue
What Happened?
of GeminiFocus was being published, the Gemini Near-Infrared Spectrograph (GNIRS) suffered a
GNIRS was warmed up in April for routine cold head
temperature controller failure that caused it to overheat.
service. The fast warm-up system and vacuum pumps
Many details and photographs of GNIRS can be found
were used following normal operating procedures that
on the Gemini web pages at: http://www.gemini.edu/
had been successfully followed a dozen times before.
index.php?option=content&task=view&id=231, where the
The fast warm-up system has a completely independent
problem was first reported to the Gemini community.
hardware controller that shuts off power to the heater
Although some significant parts were damaged, most of
resistors when the temperature set point is reached. For
the GNIRS instrument is undamaged. Gemini has started
some unknown reason, the controller failed and GNIRS
the process of restoring GNIRS to full functionality
was continuously heated until it reached temperatures of
by bringing it to Hilo, where it will be repaired and
nearly 200째 C.
returned to service on Gemini North, following the recommendation of the Gemini Science Committee.
When Gemini staff members recognized the problem,
In this article I provide an up-to-date status report on
they shut the heaters off and allowed GNIRS to cool
GNIRS and plans for its future.
passively with the pumps running for several days. After
43 www.gemini.edu