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NOTCam Status Report, Feb 1998
- The mechanical design of NOTCam was finalized with ROE in September 97
and the design was released to the mechanical fabricators, Prototech AS
in Norway soon after.
- The contract with IJAF/CUO was finalized in September 97 also and
includes the production of the array controller electronics and the motor
controller electronics together with lab testing the Rockwell arrays in a
specially fabricated test dewar. A picture of the NOTCam array mount to
be used in the test dewar and in the final NOTCam dewar can be viewed
here. Also shown are the
special 'tools' designed by IJAF/CUO staff for safe insertion and removal
of the array from the mount/holder. A
photo of the test dewar with the PTR cooler.
- The contract for the mechanical fabrication of the NOTCam mechanics was
finalized with the Norwegian company Prototech AS in October 97. Now, in
Feb 98, Prototech AS as close to completing the mechanical manufacture of
all the NOTCam parts and are close to assembly and testing incl. vacuum
testing of the cryostat. A 3D view of
the inside of NOCam, produced by Prototech AS staff from their detailed
drawings.
- Graseby Specac in England are close to finalizing the construction and
testing of the optical components for the four NOTCam lenses assemblies
(i.e. the collimator assembly, the low-res lens, the high-res lens and
the pupil imaging lens). These lens unit, fully mounted and tested,
should be delivered to NOT in March 98.
- The U.S. company Kelvin International very kindly sent an operational PTR
to IJAF/CUO for testing. This unit is the actual that would be used on
NOTCam. The PTR (pulse-tube refrigerator) was received by IJAF/CUO in Dec
97 and has been lab tested since then on a test dewar with a resistive
load. A photo of the test dewar with the PTR cooler mounted can be seen
by clicking HERE .
Test indicate that at 77K the unit has a resistive load
cooling capacity (excluding the mechanical load of the dewar) of 8 Watts.
A plot of heat load (watts) vs. temperature achieved can be seen by
clicking HERE .
This meets the requirements for NOTCam and the PTR has been accepted for
use with the real instrument. Some remaining small technical issues are
being pursued by Kelvin International who are responding extremely
rapidly and efficiently to our requests for help.
- The broad-band filter for NOTCam have still not yet been received from
OCLI. The filters ordered are 25mm in diameter and cover the J, H and K
passbands. You can go to the GEMINI web page describing the filters by
clicking
HERE .
It is anticipated that the J,H and K filters from this
consortium will arrive in La Palma in March 98. Since only slow progress
is being made on the IR Filter Consortium narrow-band filters, we have
placed an order for some 'standard' quality narrow band filters
(specifically at the moment a 1% filter at 2.122um for the v=1-0 S(1) H2
line and an associated continuum filter for this line filter).
Additional filters will be ordered if additional delays in the Consortium
order occur.
- The science grade array for NOTCam (obtained as part of the contract with
Rockwell International Science Center) has not yet been received. It is
anticipated that a science grade array will be sent by Rockwell within 2
months of the current date. However, since we are in no immediate need
for this array (the IJAF/CUO testing is proceeding with the
bare-multiplexer and the engineer grade array), it is of no immediate
consequence.
- A super-insulation blanket to cover the radiation shield of NOTCam has
been ordered from the French company Jehier. This company will tailor a
30 layer blanket from aluminized (400A) polyester film (6um thick) with
polyester tulle as spacers. This blanket will be delivered within the
next month.
- A tender will soon be placed with the British company Graticules Ltd for
a selection of slits and masks for the NOTCam aperture/entrance wheel.
These slits/masks have to be reflective on the outside (except near the
slit jaws) to reject radiation back out of the dewar and reduce heating
and blackened on the inside (facing the array) to eliminate ghosting and
stray light problems.
- Graham Cox of NOT has performed a study of the electrical wiring needs
for NOTCam and concluded that we can reduce the thermal load from
conductivity and resistivity losses by using minimum length 1m enameled
solid core copper wiring of cross-sectional area 0.08mm^2 e.g. gauge 28.
The total heat load from the wiring is expected to be 600mW.
The report produced by Graham Cox.
- The Berger Lahr 5-phase stepper motors for NOTCam have been received in
IJAF/CUO and are being tested by IJAF-CUO staff. Also, the order for the
motor positioning micro-switches from Burgess Microswitches Ltd in the
U.K. has been placed. These micro-switches should be delivered in the
next month.
- A version of the f/11 simulator (for lab testing of instruments)
has been designed by Michael Andersen of NOT. It produces a beam
longer than f/8 (f/11 for NOT and the ING WHT), has a
diffraction-limited beam from 0.35um to 2.2um over a field-of-view of
6' but is quite expensive. Discussions with the ING on our
collaboration have resulted in some mods to the design but things are
proceeding well and we are seeking additional orders for such a unit
from other Institutes/Observatories world-wide. More complete information on this telescope
simulator.
- The overall plan for commissioning of NOTCam is currently being
formalized. Commissioning time on NOT has been scheduled for Sept 98 and
it seems reasonable that we can meet that schedule assuming we encounter
no major delays. Sometime over the next month or so we will solicit
small from the NOT community projects that we can try during the NOTCam
commissioning. In addition, a talk on NOTCam and its capabilities
together with a discussion of potential projects will take place at the
'Astrophysics with the NOT' conference in Turku in August 98.
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