Integration and Verification Testing of the Large Synoptic Survey
Telescope Camera
Travis Lange, Tim Bond, James Chiang, David K. Gilmore, Seth W. Digel, Richard Dubois,
Tom Glanzman, Tony Johnson, Margaux Lopez, Scott P. Newbry, Martin E. Nordby,
Andrew P. Rasmussen, Kevin A. Reil, Aaron J. Roodman
SLAC National Accelerator Laboratory, Menlo Park, CA, United States
ABSTRACT
We present an overview of the Integration and Verification Testing activities of the Large Synoptic Survey Telescope
(LSST) Camera at the SLAC National Accelerator Laboratory (SLAC). The LSST Camera, the sole instrument for LSST
and under construction now, is comprised of a 3.2 Giga-pixel imager and a three-element corrector with a 3.5 degree
diameter field of view. LSST Camera Integration and Test will take place over the next four years, with final delivery to
the LSST observatory anticipated in early 2020. We outline the planning for Integration and Test, describe some of the
key verification hardware systems being developed, and identify some of the more complicated assembly/integration
activities. Specific details of integration and verification hardware systems will be discussed, highlighting some of the
technical challenges anticipated.
Keywords:
LSST, Camera, Integration, Test, System Engineering
1. INTRODUCTION
The Large Synoptic Survey Telescope (LSST) is an 8 m-class telescope with a very wide, 3.5 degree viewing angle that
will be used to survey the southern sky
1
from Cerro Pachon, Chile. The only planned instrument for the telescope—a
3200 megapixel digital camera
2
—is
being designed, constructed, and tested by several partner institutions led by SLAC
Natioonal Accelerator Laboratory. This paper describes the plan for integrating, testing and verifying the requirements
for the LSST Camera. It includes details of the Integration and Test (I&T) organization as well as major steps in the
integration and test process. It also includes the flow of verification activities and responsibilities from Camera
subsystem components up through the fully integrated Camera. Finally, this paper describes some of the key equipment
to be used during the I&T process and their technical challenges. Camera subsystems are all at or approaching final
design, allowing the I&T team to proceed toward final design of the integration and test equipment.
Figure 1: Cross Section of LSST Camera
2. INTEGRATION AND TEST ORGANIZATION
The LSST Camera Project consists of members from geographically diverse organizations and is managed by the
Camera Project Office at the SLAC. Within the Camera organization, the I&T subsystem interacts with all of the other
subsystems. The structure of the Camera management is shown in Figure 2, with the I&T subsystem highlighted with a
red border.
Figure 2: LSST Camera Organization Chart, with I&T subsystem shown in red outline
3. SCHEDULE OVERVIEW
The general schedule for the LSST Camera I&T covers the next four years, with delivery to the summit facility in 2020.
The level 3 milestones for I&T are shown below.
July 2017: Start Pathfinder Raft Installation into mockup Cryostat
Oct 2017:
Start Engineering Raft Installation into real Cryostat
July 2018: Start Camera assembly
May 2019: Cryostat ready to integrate into Camera
Aug 2019: Camera ready for Verification Testing
Feb 2020:
Camera complete at SLAC
4. VERIFICATION PLANS
4.1 Overview
Camera and subsystem requirements have been developed and validated according to the processes described in the
Camera System Engineering Management Plan
6
. This process strives to ensure that requirements are flowed down to the
level at which they can be verified and are fully separable from other requirements. This leads to requirements with
minimal ambiguity, and a clear understanding of the level at which they need to be verified. In general, requirements are
verified at the level where they are levied. This may require simulators or test hardware to mimic missing components
of other subsystems that are needed to fully verify a requirement. The needed functionality for such test hardware is
captured in subsystem interface documents.
Verification of interface requirements is also handled at the levels where the requirements are levied, to ensure that
interface agreements can be met at the next higher level of assembly. This may require interface simulators or test set-
ups.
Camera requirements defined in a top-level Camera specification
7
are verified through a series of tests and analyses
described below. The requirements have been grouped by verification method to aid in the development of the test.
These groupings are captured in the Camera specification along with the designated I&T verification method. The
Camera I&T team uses this as a tool to track requirement verification. The following is a partial list of verification work
planned for fully verifying Camera requirements:
Verification by Analysis
Bench for Optical Testing (BOT)
Focal Plane Metrology
Survey and Alignment
Calibrated Narrow Beam
Verification tests are performed at all stages of the Camera integration process. Tests made during integration ensure
that Camera components remain functional and provide a means to identify problems early in the integration process.
Verification tests performed at the end of major stages of integration serve to directly test that Camera requirements are
met. The tests performed by the I&T activity act in concert with requirement testing done by the various component
subsystems. I&T tests emphasize system-level requirements, including those tests which can only be performed at
system level, or where testing is needed to verify that performance at the component level is maintained at the system
level.
4.1.1 Verification by Analysis
Certain requirements can only be verified by analysis. An example is the requirement on the Camera’s image quality
(IQ), which can only be verified through an analysis combining individual test results with calculations. An IQ error tree
has been developed, tabulating each possible contributor to IQ degradation. The verification of the IQ requirement will
be performed via an analysis that follows the logic of the error tree. Each constituent requirement will be verified, either
by an I&T level system test, the appropriate sub-system test, or in some cases only by analysis. The results of these
measurements will be combined with the same methodology used in the tree: each contributing factor is measured and
the results converted into the impact on mean FWHM point-spread function in r-band, then these individual factors are
combined in quadrature, or root sum square (RSS). A number of the contributing factors may have measurement errors
of similar order of magnitude to the value of the quantities themselves. In this case, one sigma (standard deviation) of
the estimated measurement error may be included in the RSS.
Requirement:
The maximum Camera IQ Error shall be less than 0.30 arc-seconds FWHM.
The IQ error tree has multiple categories of contributions: Optical Fabrication, Raft Sensor Assembly, Assembly and
Alignment, Gravity-Induced, Thermally-Induced, Pressure-Induced and Vibration-Induced. The IQ contributions from
all of these errors are included as individual Camera requirements. Since this total IQ error includes contributions from
many subsystems, along with some that are impractical to measure without a complete telescope, they will be verified by
I&T using a combination of test and analysis.
4.1.2 Bench for Optical Testing (BOT)
The BOT will consist of a variety of verification test equipment designed to thoroughly assess the electro-optical
characteristics of the CCDs and Rafts integrated in the cryostat, but without the full Camera or optics. The BOT will
include equipment for the following kinds of electro-optical tests:
Dark images
Flat Fields
55
Fe source
Scene images: Multi-spot and single spot images
Calibrated Wide-beam images
This array of BOT tests will verify a number of the Camera performance requirements:
Noise requirements, using Dark images
Linearity and Dynamic Range requirements, using Flat Fields
Gain requirements, using
55
Fe source runs
Crosstalk requirements, using Multi-spot images
Dead Pixels, using both Dark images and Flat Fields
The section on equipment will describe the BOT in more detail.
4.1.3 Focal Plane Metrology
The dominant factor contributing to image blur in the LSST Camera is diffusion in the 100 μm thick Silicon CCDs, with
an allocation of 0.233 arcsec FWHM in the IQ Error Tree. All other factors are sub-dominant, with contributions from a
wide variety of factors. One of the largest of these secondary contributions is from errors in the flatness of the focal
plane, especially since the fast F#/1.2 LSST optics have a corresponding narrow depth of focus. The allocation for focal
plane flatness is not called out explicitly in the Camera Specification, but rather is contained inside the IQ Error budget.
The total focal plane flatness requirement is allocated over three sections of the IQ Error Tree: those for
Sensor Flatness
(0.062 arcsec)
, Raft Assembly
(0.022 arcsec) and
Detector Plane Assembly
(0.044 arcsec). The conversion factor from
FWHM to peak-to-valley flatness deviation is 0.0033 arcsec/μm, calculated assuming a uniform distribution of focal
plane heights. Thus the RSS of these three factors corresponds to a total flatness allocation of 0.079 arcsec FWHM or
±12 μm peak-to-valley deviation. (Note that this allocation includes some Camera system-level margin, above the
nominal ±11 μm peak-to-valley height requirement.)
The Focal Plane Metrology I&T effort is tasked with verifying this overall focal plane flatness requirement. Both guide
and wavefront sensors place additional requirements on their z-position with respect to the science rafts, and these too
are verified by the metrology system. No specific requirements are placed on the lateral alignment of the sensors or
rafts, aside from the obvious requirement that they do not interfere with one another. Thus the metrology measurement is
only made in the vertical, or z, direction. In addition, the requirements demand very small focal plane flatness deviations
from both gravity vector variation and thermal variation; each of these will be verified by separate analysis and not with
the metrology system. A synopsis of the metrology system requirements are shown below.
Requirement:
The metrology system shall verify focal plane flatness to ±11 μm
Requirement:
The metrology system shall verify wavefront sensor position to ±15 μm of the best fit focal plane
The focal plane consists of 21 science rafts (see Figure
6
for science raft image) and 4 corner rafts, each tension mounted
to the cryostat grid, with a tooling ball interface. The grid holds the three tooling balls for each raft in ball cups integral
to the grid, and the tooling balls fit into three v-blocks at the back of the raft sensor plate assembly to form a kinematic
mount. Adjustability is provided by the choice of tooling ball diameter, and the balls can be swapped out if necessary to
adjust the raft height. The vertical dimension requirements on the grid and rafts imply that no tooling ball adjustment
should be necessary, so this capability is a risk reduction measure.
The metrology process will be performed on the Bench for Optical Test, and is shown in more detail in the equipment
section of this document.
4.1.4 Survey and Alignment
The Survey and Alignment program is used to verify the many requirements of mechanical position and stability of the
optical elements and focal plane in the Camera.
The alignment of Camera optical elements is performed using conventional laser-tracking optical surveying methods.
Each optical element includes fiducials, typically spherically mounted retro-reflectors (SMRs), which are the reference
points for survey and alignment. The locations of the optics themselves with respect to the SMRs mounted on the optical
element’s cells are determined independently by the
Optics subsystem. The location and orientation of the focal plane
with respect to fiducials on the cryostat front face is determined by a combination of the focal plane metrology system
described in Section 6.2.3 and metrology performed by the Cryostat subsystem. The Survey and Alignment program ties
together the Camera optical elements and focal plane just through the use of the SMR fiducials.
The relevant Camera elements—the L1, L2 and L3 lenses, filters, and focal plane—include several adjustable interfaces.
The focal plane supporting structure, the cryostat grid, is connected to the cryostat via three flexures which are aligned to
set the correct focal plane-to-cryostat front face distance and orientation. A one-time adjustment of this distance is made
based on as-built measurements from the three mirrors and three corrector lenses. After this adjustment, no further
modification of the focal plane alignment is envisioned. The L3 optic, which doubles as the cryostat window, mounts
directly on the cryostat front face and thus has no adjustable degrees of freedom. The L1 and L2 optics are designed and
constructed as an integrated pair, and the optics subsystem is responsible for delivering these optics co-aligned. The
L1+L2 structure is connected to the cryostat via the Camera body structure and six adjustable struts comprising a
kinematic mount. Lastly, the filter locations are defined by the online clamp mechanism in the Filter Auto Changer,
which can also be adjusted.
The Survey and Alignment program is designed in concert with the available adjustable interfaces. Since the focal plane
and L3 are fixed in location by the time I&T performs the optical alignment, the L1+L2 structure and the filter are
adjusted with respect to the focal plane and L3.
4.1.5 Calibrated Narrow Beam
The Calibrated Narrow Beam is the test bench that verifies the integrated throughput requirements at the Camera system
level. In addition, it will be capable of measuring Camera internal reflection patterns, which when combined with
analysis, will provide a verification test of the Camera’s
optical alignment. Lastly,
it will be used to verify the camera
baffling and search for glints. Camera optical throughput is the requirement verified with the Calibrated Narrow Beam.
A summary of these throughput requirements is shown below.
Requirement:
Camera optical throughput in the u-band shall be greater than 30.3%
Requirement:
Camera optical throughput in the g-band shall be greater than 59.5%
Requirement:
Camera optical throughput in the r-band shall be greater than 63.9%
Requirement:
Camera optical throughput in the i-band shall be greater than 61%
Requirement:
Camera optical throughput in the z-band shall be greater than 54%
Requirement:
Camera optical throughput in the y-band shall be greater than 14.7%
5. CAMERA INTEGRATION AND TEST SEQUENCE
I&T’s role in the LSST
Camera development is to assemble and test the completed Camera. Once subsystems complete
verification of their deliverables, the integration of those components into the final camera assembly can begin. The
camera assembly follows the high-level sequences shown in Figure 3 and Figure 4 (note: details have been omitted;
these figures are meant to give a general overview of the process).
The integration sequence proceeds on two parallel paths for much of the initial integration effort. The work depicted in
Figure 3 is intended to run in parallel with the first steps in Figure 4. These parallel integration activities converge when
the fully loaded and tested cryostat is inserted into the completed Camera body.
Figure 3: I&T Cryostat Integration
Figure 4: I&T Camera Body, Shutter and Optics Integration
I&T has developed a detailed process for every step required to integrate and test the full Camera assembly
8
. Figure 5 is
just one page of the detailed integration process (meant as a visual only since the font is much too small to read in this
context). Each of the boxes along the main trunk of the process flow is either an integration step (yellow border) or a
verification test (red border), and each has a detailed procedure defined to accomplish the specified task. In addition, all
equipment and software required to complete the task are shown in the boxes along the vertical trunks. Since many of
the required pieces of equipment come from subsystems, this format helps the I&T team identify equipment, needed
availability, and from whom to expect it. This information is used in the master Camera schedule so all hardware and
software required to assemble and test the Camera are coordinated in time.
Figure 5: Single page from Integration and Test Flow Chart
8
(details not meant to be legible)
6. INTEGRATION AND TEST SUPPORT EQUIPMENT
The I&T team has designed several pieces of equipment that will be used to integrate and test various subsystems of the
Camera. For brevity, this paper will only highlight three of the more challenging pieces of support equipment currently
in development.
6.1 Raft Integration
6.1.1 Overview
The Raft Integration Stand is the mechanical device used to install the Raft Tower Modules (RTM) into the Camera
cryostat. The CCDs are packaged into a 3 x 3 Raft Sensor Assembly (RSA) and coupled to the Raft Electronics Crate
(REC); we refer to this combined assembly as the RTM. The RTM weighs ~10 kg, is roughly 500 mm tall, and has a
126.5 mm square footprint at the CCDs. The grid array which supports the RTM in the cryostat has a center-to-center
distance of 127 mm. Thus, one of the key challenges for installing the RTMs is the 500 μm gap between CCDs of
adjacent modules—contact between adjacent CCDs is strictly forbidden.
I&T has a self-imposed requirement to keep the CCD sensors facing down at all times in order to minimize particulate
accumulation on the sensors.
Since there is no way to support the RTM from the CCD side, the interface for I&T is on the top of the REC as shown in
Figure 6 . Due to the geometry of the camera cryostat, the process of moving an RTM from its staging position into the
cryostat requires a vertical motion of 600 mm. In addition, each RTM bay in the cryostat grid has a mechanical aperture
of 73 mm x 95 mm as shown in Figure
7
, placing further restrictions on the integration process.
Figure 6: Four tapped holes are the mechanical interface on science Raft Tower Module (RTM)
Figure 7: Vertical opening in cryostat grid bay for raft integration arm; 73 mm x 95 mm plus (4) Ø7.5 mm shafts
6.1.2 Raft Integration Mechanical Design Concept
Raft integration has two articles of support equipment: A set of stages to carry the RTM from a loading position to the
correct bay under the cryostat, and a vertical stage to draw the RTM up into the cryostat.
The X-Y stages for moving the RTM into position under the cryostat are off-the-shelf devices; position knowledge and
stage error motions are both important, but their inaccuracies will be measured using laser trackers. These stages will not
be discussed further in this document.
The vertical stage is both a tolerance challenge as well as a pendulum problem, with the tightest clearances at the end of
the long pendulum mass. The design attempts to limit both mass and length of the pendulum beam, and has very strict
tolerances on component geometry.
In order to closely couple the bearings for the vertical axis with the RTM being inserted (minimizing the unsupported
length of the integration beam), the entire vertical stage assembly will be installed in place of the vacuum seal plate at
the top of the cryostat as shown in Figure 8 .
Figure 8: Vertical stage for integrating a Raft Tower Module (RTM) into the cryostat
The support structure which sits in place of the vacuum seal plate is known as the waffle plate and can be seen in Figure
9 and Figure 10. It will be mounted to the cryostat with tip and tilt adjustability in order to make the waffle plate bay
axes collinear with the cryostat grid bay axes. To locate the vertical stage in the X-Y plane, a pattern of kinematic
features on the waffle plate that have the same tolerance scheme as the cryostat grid will be used. To accommodate small
misalignments, the vertical stage will be supported on an X-Y stage with ±1 mm travel in each direction.
Figure 9: Cross-section view of cryostat with raft integration vertical axis stage
Figure 10: Zoomed in cross-section view of cryostat
On top of the X-Y stage is a support structure which in turn supports a rotation stage. The rotation stage allows ±0.5° of
rotation in order to accommodate misalignments in rotation between the RTM and the cryostat grid. Rotation is
performed on beam flexures driven by a high-load piezo actuator as shown in Figure 11.
Figure 11: Rotation Stage with ±0.5° travel. Air bearing pads support the vertical integration beam.
Four air bearing pads, mounted to the rotating frame on each end of the rotation stage (Figure 11), support the alumina
integration arm. Vertical motion is provided by a ball screw connected to a DC servo motor with a normally-closed
brake.
In order to integrate the raft tower modules into each of the 25 grid bay locations, the entire vertical axis assembly will
be lifted from one bay location to the next as shown in Figure 12. The design allows for both 90° and 180° rotation so all
science raft bays are accessible. A separate vertical stage assembly is required for installing the four corner raft
modules.
Figure 12: Top view of cryostat showing waffle plate, and vertical stage assembly spanning 4 bays; the vertical stage assembly
will be lifted from bay to bay
6.2 Bench for Optical Test (BOT)
6.2.1 Overview
The BOT is the stand which supports the cryostat during raft integration, and will also be home to both metrology and
the suite of sensor electro-optical verification tests. As such, there are many configurations for this test stand: Raft
integration, metrology, flat fields, dark images,
55
Fe sources, single and multi-spot projectors, and calibrated wide beam.
During cryostat-only testing, no shutter will be available so the BOT will employ an exterior shroud to block all external
light. The shroud, along with internal components that can turn off light sources, allow the BOT to be used to collect
dark images (darks). Darks are used for several purposes: to verify the noise requirements, to assess dark current and
thereby bad pixels, and to collect bias images needed for the image analysis pipeline.
The BOT will have the capability to produce flat fields, with uniform illumination across the focal plane, in order to
verify linearity and dynamic range requirements. Since the flat fields will not be used to produce a calibration gain-
correcting image, uniformity is not necessary across the entire focal plane, but only on the scale of a single CCD.
The
55
Fe source configuration will include a perimeter of
55
Fe sources, isolated with electrically-actuated shutters, in a
ring that will be sandwiched between the focal plane and a flat vacuum window. The decay of
55
Fe produces x-rays with
an energy of 5.9 keV. An x-ray at this energy has an absorption depth of approximately 25 μm in silicon and will deposit
the energy via the photo-electric effect, producing 1620 electrons. Because the process is very stable,
55
Fe is ideal for
verifying gain requirements.
The BOT will contain a moveable X-Y stage to transport a small optical bench across the entire focal plane. Different
projectors or illuminators can be mounted on this optical bench. The single spot projector will be used to evaluate the
full-well and linearity of each CCD with a point source, and will also be used to study any local CCD properties such as
edge effects or the midline stop. The multi-spot projector will be used to verify crosstalk requirements.
The calibrated wide beam will be rastered across the focal plane, with overlapping spots, and the resulting images will be
stitched together to produce an effective flat field in each of the filter bands. This resulting flat field will be used to
measure the throughput of the entire focal plane. The calibrated wide beam will be capable of producing a spot in each
of the six LSST filter bands.
6.2.2 BOT Mechanical Design Concept
Figure 13: BOT shown with spots projector on left, and the calibrated wide beam spot projector on the right. The
55
Fe source is
installed for the entire duration of elecro-optical testing on the BOT.
Figure 14:
55
Fe sources mounted into vacuum spacer ring on left.
55
Fe source mounted with shutter on upper right. Actual shutter
currently being tested for particulate requirements is shown on lower right.
Figure 15: Flat field light source on the BOT; CAD model on the left and a prototype of lossy fiber with diffuser on the right.
6.2.3 Metrology on the BOT
The focal plane flatness requirement to be verified is that 91% of the CCD surface lies within ± 11 μm of the best fit
focal plane. Most of that allocation is for the sensors, with an uncertainty allocation for the metrology system of only ± 1
μm.
The metrology system employed on the BOT will use a synchronous differential measurement technique first proposed
by Rasmussen, et al
3
. This technique removes vibration/error motion of the stages carrying the laser displacement sensor
heads by simultaneously making measurements looking up at the camera CCDs and looking down at a reference flat (see
Figure 17 left). In order to meet the stability requirement, the optical reference flat must be mechanically and thermally
stable, relative to the Camera CCDs, to a sub-micron level. This will be accomplished by mounting the reference flat
with an invar hexapod structure off the front of the cryostat housing as shown in Figure 16.
Figure 16: BOT stand in metrology configuration. The reference flat is supported by an invar hexapod structure to provide thermal
stability.
Figure 17: On left, orientation of the laser displacement sensors in a differential measurement mode. On right, a synthesized map
of surface heights across the full focal plane.
The entire focal plane metrology has been simulated with an algorithm by Rasmussen, et al.
3
The results of the
metrology test will be a high fidelity height map of the focal plane, such as that shown on the right in Figure 17. This
height map will be directly used to verify the ± 11 μm requirement.
6.3 Camera Integration Stand
6.3.1 Overview
The Camera integration stand is the backbone for assembling and testing the Camera body, filter exchange system and
optics to create the LSST Camera. It is also the test stand where many of the Camera requirements will be verified;
including many of the functional tests, survey and alignment, mass properties, and system dynamics.
6.3.2 Camera Integration Plan
A high-level overview of the Camera integration sequence is shown in Figure 4, with the 3 boxes on the right performed
on the camera integration stand. The basic steps for assembling and testing the Camera are listed below.
Assemble filter carousel to Camera body as shown in Figure 18, left.
o Add filter masses and perform functional test of carousel motors, brakes and controls.
Assemble shutter to Camera body as shown in Figure 18, right.
o Perform functional test of shutter with Camera body rotated for the maximum gravity vector.
o Remove shutter.
Assemble the filter auto-changer to the Camera body.
o Load auto-changer with filter simulator and perform full exchange system functional test.
o Remove auto-changer.
Assemble complete cryostat assembly into Camera body as shown in Figure 19, left.
Assemble L1+L2 optic assembly to camera body as shown in Figure 19, right.
o Rotate Camera vertical, with L1 facing down, and verify survey and alignment requirements as shown
in Figure 21.
o Measure the integrated throughput of the Camera in the various filter bands with the camera
calibration optical bench (CCOB).
Reinstall shutter as shown in Figure 20, left.
Reinstall filter auto-changer as shown in Figure 20, right.
Install shrouds to keep the interior clean.
Measure mass properties and locate center of gravity using load cells.
Measure fundamental modes of vibration with accelerometers and a stinger to excite the structure with low
energy.
Figure 18: On left, filter carousel installation and functional test. On right, shutter installation on camera body, and functional test.
Figure 19: On left, integrating the complete cryostat into the camera body. On right, assembling the L1+L2 lens assembly to the
camera body.
Figure 20: On left, reinstalling the shutter. On right, reinstalling the filter auto-changer.
Figure 21: On left, the camera with L1-L2 pointed down for optical alignment. On right, laser tracker line-of-sight study for
survey and alignment.
7. CONCLUSIONS
The LSST Camera integration and test (I&T) team has a well thought-out plan for assembling the camera instrument and
verifying the complete list of requirements. This plan includes a set of detailed integration flow diagrams, the I&T-
designed support equipment to enable the procedures in those integration flow diagrams, and a detailed plan for
verifying the Camera requirements. Both the plan and support equipment designs are maturing to match camera
hardware design and are on schedule for meeting the 2020 delivery date for the Camera.
8. ACKNOWLEDGMENTS
This material is based upon work supported in part by the National Science Foundation through Cooperative Agreement
Award No. AST-1227061 under Governing Cooperative Agreement 1258333 managed by the Association of
Universities for Research in Astronomy (AURA), and the Department of Energy under Contract No. DEAC02-
76SF00515 with the SLAC National Accelerator Laboratory. Additional LSST funding comes from private donations,
grants to universities, and in-kind support from LSSTC Institutional Members.
9. REFERENCES
[1]
Kahn, S., “Final design of the
Large Synoptic Survey Telescope”, in [Ground-Based and Airborne Telescopes IV],
Hall, H. J., Gilmozzi, R., and Marshall, H. K., eds., Proc. SPIE 9906, in press (2016).
[2] Kurita, N. et al, "Large Synoptic Survey Telescope camera design and construction", in [Advances in Optical and
Mechanical Technologies for Telescopes and Instrumentation], Proc. SPIE, 9912, in press (2016).
[3] Rasmussen, A. et al,
“Focal
plane metrology for the LSST camera”
in [Optomechanical
Technologies for
Astronomy], Proc. SPIE 6273, (2006);
dx.doi.org/10.1117/12.673210
[4] Kotov, I. et al,
“Characterization and acceptance testing of fully depleted
thick CCDs for the Large Synoptic Survey
Telescope”,
in [High
Energy, Optical, and Infrared Detectors for Astronomy VII], Proc. SPIE 9915, in press (2016).
[5]
O’Connor,
P. et al,
“Integrated system tests of the LSST raft tower modules”, in [High
Energy, Optical, and Infrared
Detectors for Astronomy VII], Proc. SPIE 9915, in press (2016).
[6] Nordby, M. et al,
“Camera
System Engineering Management
Plan”, LCA-38,
SLAC (2015).
[7] Hascall, P.,
“LSST Camera Specification”, LCA-48,
SLAC (2015).
[8] Lange, T., Bond, T.,
“LSST Camera Integration and Test Flow Chart”, LCA-11685,
SLAC (2016).
