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PART F - PROJECT DESCRIPTION


Introduction

The success of the Systemic Infrastructure Initiative proposal for the
upgrade of the ANU and UNSW telescopes at Siding Spring Observatory (SSO)
enabled the design and construction of an innovative, powerful and unique
hyper-spectral instrument. It will be mounted at the Nasmyth A focus of
the 2.3m telescope and will take maximal advantage of the properties of
that telescope. This instrument, the Wide Field Spectrograph (WiFeS) will
provide 950 simultaneous spectra with high efficiency over the full ?eld
of view accepted by the instrument. It has a data gathering capability of
10 to 100 times the rate of the existing spectrographs.
The science mission of this instrument was defined in the WiFeS Science
Requirements Document, developed through a call for submissions to the
full Australian astronomical community in early 2002. This emphasised the
need for both wide spectral coverage and wide ?eld. At the Conceptual
Design Review (Structural), held in March 2004, its capabilities were
further enhanced by a doubling of the proposed detector format - an
option found to be both feasible and desirable within the baseline design
concept that had been developed for the spectrograph cameras. On December
6 2005 the final WiFeS design passed its Critical Design Review. However,
a full costing indicated that only the red-arm of the spectrograph could
be built within the available SII funds. Because much of the important
science cannot be done with the red arm alone, here we seek funding from
the LIEF Program to construct the blue arm and so capture the full
science potential of this innovative instrument for the Australian user
community.


The WiFeS Instrument.

The 2.3m telescope is a modest sized telescope by modern standards and
offers only a rather restrictive ?eld of view (about 6 arc min.). The
science mission of any new instrument must therefore be motivated by the
question, "Can this enable exciting, innovative and internationally
competitive science?" Given the rich breadth of research interests of the
Australian astrophysical user community of the 2.3m telescope, and the
need for the instruments on the 2.3m to enable effective student research
training at a national level, there is a clear requirement for an
efficient spectrograph versatile enough to provide outstanding capability
across a very broad range of scienti?c objectives.
The WiFeS spectrograph is designed to provide a unique 3-D spectroscopic
functionality, enabling astronomers to obtain complete spectral and
spatial coverage in a single exposure. A spatial field of 25x38 arc sec
is divided into 1.0 arc sec slices on the sky and 0.5 x 0.5 arc sec.
pixels at the focal plane. Two intermediate spectral resolution options
are available, R=3000 and R=7000. At R=3000 the spectral coverage is 3290-
5900е (blue arm) and 5100-9500е (red arm) with two ?xed gratings. At
R=7000 the spectral coverage is 3290-5580е and 5290-9120е with two ?xed
gratings per camera. This fully integral field spectrograph providing
spectra in 950 spatial elements is highly complementary to the new
intermediate resolution fibre-fed spectrograph AAOmega on the Anglo-
Australian Telescope (which is designed to observe 392 spatially disjunct
stars or galaxies across a 2 degree field).
In the design of the spectrograph great efforts were made to maximize its
data gathering efficiency to the point where it competes with 8m
telescopes working on extended objects. This is done in two ways.
Maximisation of throughput through use of :
. High-ef?ciency Volume-phased Holographic (VPH) gratings operated at
peak ef?ciency.
. High-transmission lens optics in preference to mirrors, where
possible.
. Wide-band anti-re?ective coatings on all air-glass surfaces,
reducing losses to < 1% per surface.
. Enhanced re?ectivity (>96%) multi-layer coatings on all re?ective
surfaces.
. Double-beam design to double data collection rates and optimize the
throughput.
. Large-format, wavelength-optimized, and highly-efficient CCD
detector technologies.

[pic]
Fig 1. The expected end-to-end throughput of WiFes in each observing mode.
This is more than two times higher than competing instruments of this
type. The bold lines are for the R=3000 modes; the thinner lines are the
R=7000 modes with the two sets of gratings for each camera. All the
spectra shortward of 590 nm will be taken with the optimized blue-arm of
WiFeS proposed in this LIEF bid.


Maximisation of spectral multiplex advantage and science efficiency
through.
. A double beam design to maximize the number of independent spectral
elements.
. An innovative re?ective image slicing design which maximized the
number of spatial elements, and ensures a science ?eld shape which
is well-matched to the expected science targets.
. Use of re?ective image slicing which ensures good
spectrophotometric characteristics.
. A stationary spectrograph body, which both eliminates ?exure and
provides a stable thermal environment. This ensures excellent
spectral stability over long periods.
. Implementation of "interleaved nod-and-shuf?e" allowing perfect sky
background subtraction.
. Minimization of scattered light and ghost image intensity through
careful design.
The addition of a blue arm is essential to the WiFeS science mission.
With both blue and red cameras, the full optical range can be covered in
only one or two exposures. Both cameras are required to measure important
diagnostic ratios. For stars, many important features can only be
observed with the blue-arm. These include the Balmer discontinuity and
spectral features such as the CaII H and K lines and the CN bands in the
UV. Likewise in galaxies and nebulae, the inclusion of a blue-arm allows
the important measurement of the dust reddening, and provides fundamental
density, temperature and excitation diagnostic line ratios of many
abundant elements. In summary, the addition of the blue arm will double
the data gathering capability of WiFeS. It will more than double the
science product of the instrument by enabling one to measure all the
spectral features shortward of 4200 е which are essential for stellar and
galaxy population abundance analyses. It will enhance the sensitivity of
any observations made between 4200A and 5900A through its optimized
coatings and detector. Finally, the blue and red spectra can be obtained
simultaneously, enabling increased spectro-photometric precision, and
giving the ability to monitor time-dependent spectral phenomena on short
time scales.


The WiFeS Science Mission

The WiFeS instrument will be an exceedingly powerful device, in terms of
its spectral coverage, its wavelength resolution, its ?eld of view and
its quantum ef?ciency. With at least three times the spectral coverage
throughput and an enormous number of spatial elements accepted, it will
operate up to 30 times faster than the current 2.3m Double Beam
Spectrograph (DBS) in extended objects or 10 times faster for individual
stars. It has exquisite sensitivity, reaching a limiting magnitude of
about V=22 mag or surface brightnesses of order F ~ 10-17erg s-1 arc sec-
2 е-1 - this is a sensitivity comparable to the best of the current-
generation spectrographs on 8m-class telescopes for extended objects.
The spectrograph is ideally matched to both its site and its telescope.
This is achieved through matching the spatial resolution to the expected
seeing, maximizing throughput, and through the ef?cient use of the
detector real estate. As a result, its information gathering capability
is competitive with spectrographs on much larger telescopes and at better
sites.
Within Australia, WiFeS will offer unique capabilities, since an
equivalent integral ?eld option is not likely to be offered on the
AAOmega instrument at the Anglo-Australian Observatory. In addition, its
much higher throughput (35% c.f about 15%), its ability to do
quantitative spectrophotometry over an extremely wide spectral range in
all spatial elements, coupled with the fact that the packing ef?ciency of
these spatial elements on the sky is 100%, makes WiFeS unique in the
world.
With such impressive capabilities and versatility, the science mission of
the WiFeS spectrograph is correspondingly broad, and encompasses most of
the research interests of the Australian astronomical community. Major
components of the Science Mission include:
. Determining the chemical enrichment history of the oldest stars.
. Measurements of the abundances in stars and chemical enrichment in
Globular Clusters.
. Using Gamma Ray Burst Sources as probes of the epoch of re-
ionization of the Universe.
. Studies of abundance gradients and the chemical enrichment history
of galaxies.
. Mapping the dynamics and heavy element content of supernova
remnants.
. Studies of the internal dynamics of galaxies to resolve the cusp:
core controversy.
. Understanding starburst galaxies and the circumnuclear star-forming
regions.
. Studies of anomalous gas kinematics around the active nuclei of
galaxies.
. Studies of the assembly and of active nuclei in high-redshift radio
galaxies.
. The detection of Lyman-break galaxies over a wide redshift range in
blind searches.
. Radial velocity surveys of the cores of rich clusters of galaxies.
. Investigation of the internal structure, excitation and dynamics of
Planetary Nebulae.
. Understanding the structure, excitation and dynamics of Herbig-Haro
Objects.
. Investigating the physics of the nova eruptions in our Galaxy.
. Investigating the accretion and assembly history of our Galaxy.
. Measuring the initial mass function at low stellar mass, and
studying Brown Dwarf stars.
WiFeS will become the major instrument on the 2.3m telescope, freely
available to all Australian users through the Time Assignment Committee
peer review process. We present below a few highlights of the science
case which illustrate the remarkable potential of the blue-arm
capability.


3.1 Point sources

Single Stars. Although not speci?cally designed for observations of point
sources such as stars, WiFeS nonetheless offers a number of important
advantages over classical long slit spectrographs. Its throughput is ~3
times larger than either the DBS or AAOmega instruments. The wavelength
coverage in a single exposure is very wide, requiring only a single
exposure at R=3000, and two at R=7000 to cover the whole spectral range
3200-9100е. Most instruments effectively cut off at wavelengths of 3500-
3700е, so WiFes will notable in being able to observe features such as
the NH molecule at 3360е. The instrument accepts 100% of the light of the
star without degradation of the spectral resolution, regardless of the
seeing. Since the seeing at Siding Spring may be as poor as ~3 arc sec,
this can provide more than a doubling of observational ef?ciency on the
brighter stars.
WiFeS also offers a "nod-and-shuf?e" capability in which exposures on-
target and on-sky can be interleaved in a single exposure and on the same
detector pixels. This allows perfect sky background subtraction, and
provides sky-noise limited spectrophotometry at all wavelengths for faint
stellar sources with 50% on-target duty cycle.
Clearly, all of these factors do not apply to all the observations that
it is possible to make on stars, but overall, they ensure that the
observation time to reach a given signal to noise ratio is reduced by a
factor of anywhere between 3 and around 20 over the existing DBS on the
2.3m telescope.
WiFeS becomes sky-limited at U=22.0, B=22.7, V=22.0, R=21.0, and I=19.2.
For a 22 mag star (at all wavebands), and under seeing conditions ~1 arc
sec., the exposure time needed to provide sky-limited exposures with a
S/N=10 per resolution element in the R=3000 mode is of order 5.8Hr (U),
1.2Hr (B), 1.4Hr (V), 1.8Hr (R) and 4.4Hr (I). Thus, the effective
limiting magnitude in the R =3000 mode is 22 mag, or perhaps a little
fainter, depending on the S/N required.
The operating resolution of WiFeS is driven in part by the need to obtain
stellar rotational velocities, particularly for young stars. This
provides clues about magnetic activity, accretion disk phenomena and star
formation history. It is also important in the investigation of stellar
winds, mass-loss and disks in B stars evolving away from the main
sequence. At the full WiFeS resolution of 45 km/sec (R = 7000),
rotational velocities can be measured from emission lines, but more
importantly, from photospheric absorption lines. MgII 4481е is often the
line used in the case of B and A stars.

The First Stars. The first stars are thought to form in small proto-
galactic clumps very early in the evolution of the universe. These clumps
gradually merged with other clumps to build up larger galaxies like the
Milky Way. Within the Milky Way, it is possible to find stars that formed
so long ago that they contain only a tiny fraction of heavy elements. The
most metal-poor star so far discovered has less than 1/100,000 of the
iron content of the sun. Its chemical enrichment must have been affected
by only one of the element building supernova events. The relative
abundances of chemical elements in these stars provide a unique insight
into chemical conditions in the early universe - so they are highly
sought after.
Amongst the first stars to be formed in the collapse and formation of our
Galaxy were the extremely metal-deficient stars in the regime [Fe/H] <
-3.0, or below. These will be prime targets with the WiFeS spectrograph
and the new SkyMapper telescope will provide many thousands of such
candidates between 17 and 20th magnitude using photometric color
selection. In order to get a more precise quantitative estimate of the
metallicity, we need to obtain blue spectra and measure the CaK (3933е)
line, the H?, and H? lines, the Balmer discontinuity and a variety of
molecular species including CH (4300е), CN (3850 and 4215е), C2 (4700-
5200е) and NH (3360е). All of these are best measured at the resolution
of 45 km/s (R=7000) offered by the WiFeS spectrograph. In addition, the
derivation of temperatures from colors such as B-V can be done using
spectrophotometry with WiFeS which provide excellent resolution over a
very broad wavelength region at very high efficiency and with high
stability. The most interesting stars found with WiFeS will be candidates
for observing at the highest resolution with the 8m class telescopes
Gemini, Magellan and the VLT.
Clusters of ancient stars are found in the globular clusters.
Observations of these would complement and strengthen important northern
hemisphere work on the integrated spectra of Milky Way and M31 globulars
(Burstein et al, 2004, ApJ, 614, 158). These authors report large and
inexplicable abundances of nitrogen that have been argued to hold
important implications for the formation of the ?rst stars in these
systems and the origins of globular clusters themselves. WiFeS will
facilitate very ef?cient observations of critical southern Milky Way and
Magellanic Cloud systems to better constrain the implications of these
results. The ability of the WiFeS instrument to access the important NH
molecule at 3360е will enable it to make important observational
contributions.
Gamma-Ray Burst Sources (GRBs). WiFeS observations of GRBs offers the
opportunity to answer one of the fundamental Big Questions motivating
modern astrophysical research: "When did the ?rst stars form, and how did
they end the dark ages?"
When matter and radiation in the Universe decoupled at a redshift of
about 1000, the ionized matter recombined and became temporarily neutral.
Later, as the ?rst stars formed, their radiation reionized the Universe
into the form that we see it now. We now believe that this epoch of re-
ionization occurred at a time between redshifts of about 6 and 20 (Kogut,
2003, New Ast. Review, 47, 977). Re-ionization profoundly changed the
universe, and greatly affected its subsequent evolution: we need to know
the redshift of this epoch much more precisely. GRBs are ideal probes for
this work, and we will use them to investigate how the state of the
universe changes with redshift. The shortlived GRBs will be detected by
observations with the SWIFT satellite and these can be identi?ed and
their brightness measured, with rapid follow-up optical observations at
Siding Spring, using either the Skymapper Telescope or the 3rd-generation
robotic telescope, ROTSE-III, run by UNSW in collaboration with the
University of Michigan at SSO. However, only the WiFeS instrument will
have the capability to make spectroscopic observations at early epochs.
The Gamma Ray Bursts (GRBs) are stellar explosions which release more
energy in a few seconds than is emitted by whole galaxies. Their
radiation is highly beamed, enabling them to be detected across the
Universe. The situation for follow-up work is ideal as long as the Swift
GRB satellite is operational, since this provides positions to within 15
arc sec within a minute of the burst. An IFU with a ?eld as large as
WiFeS is the perfect instrument to obtain rapid time-resolved
spectroscopy of the afterglow in the ?rst few minutes after the burst,
since there would be no need for acquisition with such an instrument - we
are guaranteed that the optical counterpart of the burst source will lie
somewhere within the ?eld of view of the instrument. The objectives of
the intensive spectroscopic observations that would follow in the ?rst
night following discovery are to trace the early spectral and photometric
evolution of the continuum, to look for associated absorption lines, to
obtain insight into the environment of the event, to discover the
redshift of the host galaxy, and to investigate the absorption and
emission in the intergalactic medium along the line of sight and so
obtain insight into the evolution of this medium through space and time.
In the case of the most distant events, z > 6, these observations will
provide essential information about the epoch of re-ionisation which
terminated the "dark ages".

3.2 Extended Sources

Early-Type Galaxies & Massive Black Holes. A great deal of vital
information about the star formation in the early universe, and about the
history of galaxy mergers can be discovered through studies of elliptical
galactic dynamics and abundances. These require an integral ?eld
coverage, over a ?eld commensurate with the sizes of nearby elliptical
galaxies. This ideally implies a ?eld of view of order one arc min.
Although the WiFeS spectrograph will require several telescope pointings
to achieve this useable ?eld, it has the fundamental advantage of being
capable of delivering absolute spectro-photometry at every point in the
?eld. This is something that is impossible, or at least very dif?cult,
with ?bre-fed spectrographs. As has been done with Sauron
(http://www.strw.leidenuniv.nl/sauron/) in the north, a single exposure
would yield the velocity ?eld, the chemical abundances and abundance
ratios, and ages of the stars. In addition, the environment of any active
galactic nucleus can be probed dynamically and through the excitation of
the surrounding gas. Such a complete picture of a galaxy cannot be
achieved with other instruments. WiFeS has the capability to deliver much
more information than Sauron in a single exposure, and over a much wider
wavelength region.
The ideal wavelengths of operation for this application would be to
observe in the wavelength range from [NeV] to [NI] in the blue (3400-
5300е), and from HeI to the Ca triplet in the red (5800-8700е). These
wavelength ranges should be observed simultaneously to avoid registration
and photometric uncertainties. This is enabled in the WiFeS double-beam
design. Since this allows for a nod & shuf?e mode of observation, one can
also reach down to the limits imposed by Poisson noise. The WiFeS
resolution of about 45 km/sec in the blue is ideal for dynamical studies
or for extraction of the very narrow band spectral indices used for
population synthesis in both spiral and elliptical galaxies.
Colliding Galaxies. Interactions between galaxies are fundamental to
theoretical models of galaxy evolution. Galaxy interactions can explain
the formation of ellipticals, outbursts of vigorous star formation, the
formation of globular clusters and of dwarf galaxies. Interacting
galaxies can also be the precursor to the formation of active galactic
nuclei (AGNs) . It is almost inevitable that an interaction between two
galaxies is accompanied by vigorous star formation, initially triggered
by tidal interactions, and resulting in strong FIR radiation from heated
dust. In the late stages of the merger, gas from the merging galaxies may
be accreted to the central regions to power an AGN. The likely evolution
sequence is as follows. First, a merging event produces tidal arms with a
double nucleus, later a confused morphology with either starburst or AGN
activity or a mixture of the two, and ?nally a single elliptical galaxy.
The WiFeS spectrograph would be used to map the detailed velocity ?eld in
the merging galaxies, and to dynamically distinguish any extended narrow-
line emission associated with active nuclei. For this purpose, both high
spatial (1 arc sec) and spectral resolution (R7000) over as wide an
integral ?eld as feasible are required. Double-beam operation is required
to enable simultaneous observation in the H?, [O I], [O II], [N II] and
[S II] lines in the red, as well as the HeII, H?, [OIII], and [N I]
emission lines, and at the same time as having suf?cient resolution to
measure the Ca II and Mg b stellar absorption features in the blue. This
requires a wavelength coverage of at least 4600 -5400е in the blue, and
6200 -7400е in the red.

Grand-Design Spiral Galaxies. Despite over thirty years of study,
data on the chemical abundance of spiral galaxies still remains
remarkably sparse. The fundamental reason is that observing the usual
abundance indicators, HII regions, at the rate of one or two at a time is
incredibly expensive in terms of telescope time. Exposure times are
necessarily long in order to measure the elusive electron-temperature
sensitive [O III] 4363е line. However, Kewley & Dopita (2002, ApJS, 142,
35) have developed new methods to obtain accurate abundances using only
the bright emission lines.
Nowadays, dynamical and chemical evolution modelling has become a science
rather than a black art, and we can now predict the chemical evolutionary
state of both the gas and the stars, predict the run of star-formation
with radius, and use stellar evolutionary synthesis to predict the
stellar spectrum throughout the galaxy. It is therefore high time to
return to making such observations with an integral ?eld spectrograph, in
order to test this sophisticated theory, and to better understand both
the galactic evolution and the chemical yields from massive stars. Such
observations would also permit the discovery of unusual objects such as
supernova remnants, or extreme mass-loss Wolf-Rayet stars.
The key to success in such observations is to have as wide a spectral
coverage as possible. For example one of the key diagnostic ratios
required to obtain the metallicity in the high-abundance HII regions is
[NII] 6584е / [OII] 3727е . To accurately correct this ratio for
reddening we would need to simultaneously observe the H? /H? ratio.
However, to obtain the ionization parameter, we need either the [O III]
5007е / H? ratio or the [O III]5007е /[O II]3727е ratio. For the study of
stellar populations we also need as wide a spectral range as possible,
from the CaII and CN lines in the blue up to the Ca triplet in the red.
The WiFeS resolution of about 45 km/sec in the blue is ideal for
extraction of the very narrow band spectral indices which are used for
population synthesis.
Needless to say, the ?eld should be as large as possible. Typical
individual giant HII regions are 100-200 pc in diameter, so that they
subtend one arc sec (~best seeing) at a distance of 20-40 Mpc. At this
distance, a typical spiral galaxy will still subtend ~2 arc min on the
sky, so observation of a complete galaxy will still require the tiling of
a number of WiFeS ?elds (10-20). However, since each ?eld would only take
of order 1/2 Hr, the whole galaxy could be covered in a single night of
observation.
High-Redshift Radio-Galaxies. There is very strong evidence that
the bulges of galaxies and the black holes which they contain grew
coevally. Equally, the high-redshift radio-galaxies (HiZRGs) are now
understood to be the places where the most massive black holes were
formed and where today one ?nds the ?rst-ranked ellipticals in galaxy
clusters. In fact, the near infrared "Hubble" K-z diagram shows that the
radio-loud host galaxies are the most luminous at any redshift 0 < z <5.2
(De Breuck et al. 2002, AJ, 570, 92).
These galaxies are observed to be forming stars at an extraordinary rate,
in excess of 1000 solar masses per year, and their morphologies show
clear evidence for strong interactions between the radio jets and the
surrounding ISM. They are observed to be surrounded by very extensive
shock-excited regions, and enormously extended Lyman alpha (L?) halos
(>200 kpc ~20arc sec.; Reuland et al. 2003, ApJ, 592, 755). In order to
understand the nature of these interactions, the importance of triggered
star formation and the likely evolution of these sources, we require
integral ?eld spectroscopy. Although WiFeS is mounted on a relatively
small telescope, it can make a very useful contribution in this area
because its ?eld of view is large enough to accept all of the nebulosity,
and the sensitivity is limited only by the surface brightness of the
source, so telescope size is immaterial unless very high spatial
resolution is required. By far the most interesting line is L? which can
be readily detected, and observations over a full night would be
suf?cient to provide line pro?les with a useable signal to noise across
the extended halo. Such objects will be prime targets for the instrument.

The L? pro?les which have been observed with UVES on the VLT are both
very complex and spatially variable (Figure 2), and show evidence for
expanding broken shells of gas around these objects. The narrowest
features here are ~2е wide, well matched to the capabilities of WiFeS in
its R = 7000 mode.
[pic]
Fig 2. The L? profile of the central 2.5 arcsec of 0200+015 (left) and
for a region displaced ~2 arcsec to the north, coincident with one of the
radio lobes of this galaxy at redshift z=2.23 (data from Wilman et al.
2003, NewAR, 47, 279).
In addition to the extended L? haloes, a number of discrete sources are
usually detected surrounding these sources within a few arc minutes.
These are more normal star-forming galaxies which will later make up the
cluster around the radio galaxies. Typically, they are found at a surface
density ~15 times the average at these distances (Venemans et al, 2002,
ApJ, 569, L11-L14). Thus, "looking under the lamp post" around HizRGs at
enables us to understand the formation process of galaxies at the
earliest epochs (z > 4).
Distant star-forming galaxies. These objects, termed Lyman Break
sources, have been identi?ed in blind searches of large areas of sky,
mostly through their broad-band photometric properties. They turn out to
be very abundant, and are certainly related to the formation of lower
mass galaxies than the radio galaxies discussed in the previous section.
Many of these have also been identi?ed through their L? emission, and
appear to contain little dust. Star formation rates are inferred to be of
order 40 solar masses per year, giving L? line ?uxes in the range 1-5x10-
17 ergs s-1. Since the line widths in these galaxies are narrow, such
objects could be readily detected with WiFeS in blind searches.
The procedure would be to make "nod-and-shuf?e" observations between two
blank patches of sky. Lyman-break galaxies will appear as a positive
signal in the data if they are in one aperture, or a negative signal if
they are located in the other. Lyman-break galaxies are expected to be
found at 2 < z < 3 (3600е - 4900е). At distances beyond z ~ 3, cosmic
dimming is expected to lower the line ?ux below the detection threshold.
We expect to discover sources at the rate of about 10 per night. Such
high rates of detection may seem surprising, given the relatively
restricted search area (0.43 arc min2). However, limitations of the beam
width are more than made up for by the depth of the search space, giving
detection ef?ciencies are similar to narrow-band surveys covering many
arc min. square.

The Proposed WiFeS Blue Camera


1 Mechanical and Optical Design

[pic]
Fig 3: Cross-sectional engineering design drawing of the blue camera
optics. The VPH grating is at the left, a total of 10 lenses make up the
camera optics. The focal plane shown at the right represents the CCD
surface. The 10th lens acts as the dewar window. The dewar itself is not
shown. The focusing mechanism is at the top right.

|Lens # |material name |Diameter mm |Thickness mm |
|Lens 1 |Fused silica |193 |31 |
|Lens 2 |CaF2 crystal |193 |69 |
|Lens 3 |BAL35Y |193 |69 |
|Lens 4 |S-FPL51Y |205 |46 |
|Lens 5 |CaF2 crystal |171 |65 |
|Lens 6 |BAL35Y |171 |59 |
|Lens 7 |S-FPL51Y |149 |69 |
|Lens 8 |Fused silica |149 |51 |
|Lens 9 |BAL35Y |149 |28 |
|Lens 10 |S-LAL7 |105 |32 |


2 Budget background

The blue-arm of WiFeS is not an off-the-shelf item. However, many of its
components can be bought commercially, including the VPH gratings, the
CCD detector and electronics and the Cryo-Tiger cooling system. The major
expense is the custom-made large diameter optics. These use expensive,
exotic and fragile materials, such as CaF2 and high refractive index UV-
efficient glasses. Several competitive quotes have been obtained for this
work much of which, unfortunately, needs to be undertaken overseas.
However, mechanical design, integration and testing can be done most
effectively in the RSAA or AAO workshops. The detector package will be
done at RSAA by one of the best CCD engineers in the world, Paddy Oates.
The blue and red detectors and dewars are identical in their electrical
and mechanical properties so the additional costs for the blue detector
setup is relatively low.
We have divided the budget into off-the-shelf (OTS) procured items,
subcontracted fabrication items and labour for design, making
construction drawings, assembly and test. The design and drawing work is
work to completion, the blue-arm is almost fully designed in detail. Some
capital items have been already purchased for the blue-arm (the blue
gratings for instance) and are not included in the budget.
The budget for the blue-arm of WiFeS has been calculated bottom-up from
the 14 individual detailed work-packages using labour costs based on 2007
internal RSAA rates (excluding overhead).
The hourly rates range from $55 for workshop time to $77 for engineering
and software design. Were parts of the work to be sent to outside
contractors the labour costs would be higher unless we receive similar
discounted rates. We are confident in our costings as we are proceeding
with the construction of the red-arm of WiFeS based on similar
calculations. The reasonable labour contingencies are based on experience
of previous completed work-packages.
These work-packages are the Dichroic Beamsplitter Mechanism, the Blue
Disperser Mechanism, Blue Camera Housing and Focus Mechanism, Blue Camera
Optics and Cells, Blue Camera Assembly Integration and Test, Blue Camera
Handling and Test Support Equipment, Blue Detector Assembly, Blue Cryo-
Tiger Cooling System, Blue Cryostat Assembly, Blue Detector Functional
Performance Tests, Blue Arm Retrofit, Detector Control System Hardware
and Cabling, Detector Characterisation. Finally, there is a new software
work package for the Data Reduction Pipeline and Archiving.
The 10% non-labour contingency is again based on experience but is also
overlayed with significant foreign exchange exposure as most of our OTC
purchases are in US dollars as are our subcontracts for optical
fabrication. We have used an exchange rate of 1 Aus = 0.75 US dollar.

3 Data reduction Pipeline and Archiving

For ease of observing and for best practice flux calibration and
archiving efficiency it is important that the data be reduced with a well
designed optimum pipeline. This will ensure that all data taken is
properly calibrated and then archived as part of the Australian Virtual
Observatory. WiFeS is designed to be operated at either one or two fixed
grating positions depending on the grating used and which resolution
option is chosen. This means that the required instrumental calibration
procedures are minimal for observers and the data reduction pipeline
should be relatively straight-forward. It cannot be overemphasized how
important is good pipeline data reduction and archiving. Provision of
pipeline data reduction and archiving packages is integral to new AAO,
HST, ESO's VLT and Gemini instrumentation and is the key reason why data
from these telescopes are quickly published, archived and made publicly
available within a very short time. Provision of such a pipeline for
WiFeS will make it much easier to guarantee that high quality data is
obtained by inexperienced users. All data can then be made available to
the community through the Virtual Observatory. This work-package will
likely be undertaken by the University of Queensland who are already
involved in the Virtual Observatory.

4 Cost of Optics

The most expensive budget component ($228K) is the camera lenses and
fabrication. Quotes were obtained separately for the optical stock
material and for the optical fabrication. The fabrication quotes
(attached below) covered a large range, more than a factor of two. The
most expensive quote was from the New Zealand optics company Kiwistar. We
propose to accept the Coastal Optical System quote which was the most
detailed and careful. Coastal have a good reputation for delivering
excellent optics for astronomical cameras for seven large USA
Observatories.

The optical stock was sourced from Ohara (BAL, S glasses), Schott (CaF2)
and Dynasil (fused silica). Some of the exotic glasses and the CaF2 have
large lead times of 8-10 months. The lens fabricators have warned that we
should have spares for some of the fragile glasses and CaF2 components as
they could break during manufacture. We have included some selected spare
blanks in the budget. All lens surfaces with glass-air interfaces have
multilayer anti-reflection coatings applied. The coatings are devised to
maximize throughput in the blue spectral region and to avoid optical
ghosting. The state-of-the-art AR coatings are one of the reasons for the
very high throughput of the blue-arm of WiFeS. Quotes for the coatings
are also listed with the fabrication quotes.


A partial breakdown of the capital and subcontracted components of the
work-packages is given in the following table. The bracketed costs in the
first two work-packages are for items already bought.

|Work package |Off-Shelf |Fabrication |Contingency |
| |Procurement |Subcontract | |
|Blue Beamsplitter |(1.4K) | (16.8K) |(2.2K) |
|Mechanism | | | |
|Blue Disperser |(1.4K) |(65.2K) |(2.5K) |
|Mechanism | | | |
|BlueCamera Housing |2.2K | 15.2K |5K |
|and | | | |
|Focus Mechanism | | | |
|Blue Camera Optics |98K |130.0K |2K |
|Blue Blue Camera | | | |
|Assembly | | | |
|Integration and Test | | | |
|BlueCamera Equipment| |4.2K | |
|Blue Detector |106.7K | | |
|Assembly | | | |
|Blue Cryo-Tiger |29.0K | | |
|System | | | |
|Blue Cryoostat | |16.8K |3K |
|Assembly | | | |
|Blue DetectorTests | | | |
|Blue Arm Retrofit | | | |
|Detector Control |29.0K | |1.4K |
|System | | | |
|Hardware and Cabling | | | |
|Detector | | | |
|Characterisation | | | |
|Data reduction | | | |
|pipeline | | | |
|Subtotals |$264.9K |$166.2K |$ 11.4 |




5 Summary Budget


Fixed costs Calculated Contingency Total
OTS procurement $264.9K $ 0.0K $264.9K
Subcontracted fabrication 166.2K 11.4K 177.6K
Freight/insurance 8.3K 0.0K
8.3K
Travel/subsidence 2.5K 0.0K
2.5K
Total fixed costs $453.3K
Plus 10% contingency 45.3K
Total fixed costs $498.6K

The breakdown of the labour in the combined work-packages is as follows:

Labour costs Hours Contingency Total
Mechanical Engineering 263 40 $ 23.4K
Electrical Engineering 84 13 6.8K
Optical Engineering 342 51 28.0K
Detector Engineering 130 20 11.6K

Software Engineering 155 23 13.8K

Electrical Technical Officer 172 26 10.7K
Mechanical Workshop 33 5 2.0K
Data reduction pipeline 680 100 60.0K
Project Management 61 9 5.8K
Total labour 1920 287 $162.1K


Total cost: (Fixed + Labour) $660.7K
F3 Supporting Documentation - Quotes
(AUD = 0.75 USD assumed throughout)

F3.1 Optical Fabrication Quotes (Confidential)
The optical fabrication quotes given below are from companies with known
fabrication capabilities in this type of camera. Manufacturers show a wide
range in costs, delivery times and process control.

|ARC LIEF: Australian Membership of the Gemini| | | |1458 |1462 |
|Telescopes | | | | | |
|ARC DP: Uncovering the fossil record of | | | |92 |83 |
|galaxy formation | | | | | |
|ARC LIEF: Australian Astronomy Grid | | |464 |142 |330 |
|ARC(DP) Galactic Cannibalism: the link | |95 |85 | | |
|between. | | | | | |
|ARC(Linkage) Galaxy Recycling in clusters of | |10 | | | |
|galaxies | | | | | |
|U. Queensland Research Development: A new | |60 | | | |
|understanding of star formation in the Local | | | | | |
|Universe | | | | | |
|ARC(DP) Formation and Evolution in the |330 |306 |290 |217 |212 |
|Extragalactic Universe | | | | | |
|ARC (SR) Smart astronomy: using computational| | | |34 |34 |
|science to | | | | | |
|understand distant radio galaxies | | | | | |