A Dynamic Structures team visited Maunakea in late April to review the shutter system
enclosure. They also took metrology data on
the arch girders and top shutter in various
positions. They are currently reviewing these
data, and we expect their final report in July.
Figure 2.
“Before and After”
images of FLAMINGOS2’s thermal background
in spectroscopy mode,
with the baffle not
correctly in place (left
panel) and correctly in
place (right panel).
FLAMINGOS-2 Stand-down
Successfully Completed
In March, FLAMINGOS-2 was given a preventive maintenance stand-down, in which we
fixed the gate valve baffle issue and installed
a spectroscopic K-band filter. The gate valve
baffle, stuck in place since late 2014, is now
working well, returning the thermal radiation
from the gate valve to nominal levels in spectroscopy mode (Figure 2).
Figure 3.
Charge transfer/
smearing in Chip
1 of the GMOS-S
CCD array. See the
instrument status
and availability
pages for more
details here.
GMOS CCDs
The Gemini South Multi-Object Spectrograph (GMOS-S) Hamamatsu CCDs have suffered some significant issues since their installation in May 2015 — namely, saturated
pixels affect significant patches of the
channel they find themselves in. Now
a fix (in the form of new-revision video
boards) is on the way.
However, a further issue surfaced in
April, involving an apparent smearing
of charge in CCD1, particularly evident
in nod/shuffle mode (Figure 3). Principal
Investigators (PIs) were contacted and
some workarounds have been devised,
but the effect remains significant for
many programs. Plans are in place to address the problem during June-July bright
times (as this issue goes to press).
Meanwhile, plans for installation of Hamamatsu CCDs in the north are pending the o