perature of 80 Kelvin (K). Because F-2 is sen-
sitive to part of the thermal region of the
NIR (up to 2.5 microns), the masks and the
instrument’s front section are inside a fron-
tal cryogenic dewar. In order to exchange
the MOS masks, the frontal dewar has to
be thermally cycled between the ambient
temperature and atmospheric pressure,
and then back down to 100 K and high vac-
uum. The next step is to test the engineer-
ing procedures and install a batch of masks
for science commissioning, planned for the
week of March 27th. The next step is to test
the engineering procedures and install a
batch of masks for science commissioning,
planned for the last week of April.
Update on K-band Filters
for F-2 (K2F2)
In Semester 2017B, Gemini will offer in
shared risk mode two medium-band filters
for splitting the K-band (1.9–2.5 microns): a
K-red filter (2.19–2.44 microns) and a K-blue
filter (1.94–2.17 microns). We have received
the filters from Texas A&M University as
part of the K2F2 project — a Small Project
for Instrument Upgrades awarded funds in
2016 (Figures 18 and 19). The filters will be
installed during a scheduled instrument
shutdown spanning April 6–18. On-sky ac-
ceptance tests will follow, with science com-
missioning slated for May.
— Rubén Díaz
Figure 18 (left).
The K-red filter on the
left and the K-blue filter
on the right. Images
were obtained during
the filters’ physical
inspection.
Figure 19 (right).
Reflections of Gemini
South Science Fellows
Karleyne Silva and
Veronica Firpo, left and
right, respectively.
January 2018 / 2017 Year in Review
GeminiFocus
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