JWST IFUs and Data Tool
Development Plans
Tracy Beck
JWST NIRSpec Instrument Scientist
Integral Field
Spectroscopy… with JWST!
IFU Data Cube
Integral Field Units – provide 3-D
imaging spectroscopy of a small region
of the sky – every image location has a
(R~3000) spectrum associated with it!
Y (spatial)
JWST NIRSpec – 1-5mm IFU
With a 3” x 3” field of view (0.”1
square spatial sampling)
X (spatial)
JWST MIRI – 5-25mm IFU spectra
acquired with 4 IFUs. IFU spatial
fields scale with wavelength. This
“MRS” mode is MIRI’s ONLY
R=3000 spectral capability!
STScI Sponsored Workshop “IFUs in the Era of JWST”
• Oct 26-28, STScI hosted the first major international
workshop on Integral Field Spectroscopy to take
place in the US
• 60+ Astronomers and Instrument developers from
four continents participated
• All talks are archived: https://webcast.stsci.edu/webcast/
(view the archive for the week of Oct. 25th)
• IFUs are in our Future!
• ~15 IFUs presently in operation at ground-based telescopes
• 2 IFUS on JWST, MIRI and NIRSpec
• First-light IFU instruments planned for both TMT and e-ELT (the
latter has 2)
IFU Data Analysis Tools
Science from IFU surveys is making an impact, but
the results are often very slow in coming…
IFU Users are experts at “reinventing the wheel” – by
necessity!
Robust, widely adopted data analysis tools don’t exist for IFU
data. Very Common Data Analysis for IFU sets:
• Basic Data cube addition/subtraction (some tools exist)
• Automated profile/dispersion fitting for basic kinematic
analysis (Does not Exist)
• Make IFU velocity channel maps or movies for
publication/presentation analysis (Does not Exist)
IFU Data Analysis Tools
IFU Users are experts at “reinventing the wheel” –
by necessity!
“Qfitsview” – one of the
most popular 3-D cube
visualization tools
(work with images &
spectra at the same time)
Very Common Data
Analysis for IFU sets:
Basic Data cube addition/subtraction – combine multiple 2-D image
planes to form an average image, or 1-D spectra to make an average spectrum. Fit
continuum and subtract from an emission line, to make an emission line map.
(Exists in some viewing tools – BASIC functionalities).
IFU Data Analysis Tools
Very Common Data Analysis for IFU sets:
Profile/dispersion fitting:
Ha emission
Ha velocity
Ha dispersion
Fit a Gaussian or line profile to
an emission line, or crosscorrelate a template to a
spectrum, to derive kinematics in
a target. (velocity, dispersion)
z~2 galaxy From Forster-Schreiber et al. (2006)
If a datacube “visualization tool”
does not provide a means to
make publication quality figures,
users will need to use a different
environment to do that, and the
tool won’t be widely adopted. Jet from a young
star - Beck et al.
Make velocity
channel
maps or
movies for
publication
and
presentations
IFU Data Analysis Tools
IFU Users are experts at “reinventing the wheel” –
by necessity!
Very Common Data Analysis for IFU sets:
• Basic Data cube addition/subtraction (some tools exist)
• Line Profile/dispersion fitting for basic kinematic analysis
(Does NOT Exist)
• Make velocity channel maps or movies for
publication/presentations analysis (Does NOT Exist)
IFU Data will be more accessible and easier to work
with and publish for all JWST users if we don’t have to
start from ‘step 1’ for these very common data analysis
techniques
• IFU Data Analysis Framework document, by
Bacon, Beck, Greenfield & Stiavelli (ESO /
STScI collaboration)
ESO’s IFU Development
Plans
• ESO - Development is very strongly linked to their
complex 1’ x 1’ field of view IFU, “MUSE” (300 x
300 x 4200 size datacubes). First light  2012.
• Wrote requirements for an IFU cube analysis tool,
and looked at available options
• Recent decision: work with NRAO to update/adapt
the “CASA Viewer” that exists for radio data and is
being further developed for ALMA
• ESO is a partner in ALMA, and so will be a strong
contributor to the CASA Viewer development work C++ Backbone,
• We will keep all communication channels open for viewer has Qt
this development.
GUI interface
– CASA Viewer has no capability for plug-in expansion
by users (or us) 
– STScI has no means of visibility into this
development. 
STScI IFU Development
• Goals –
– Provide visualization and analysis tools that will
optimize IFU science return for non-expert
users, to improve impact and usability of the
JWST IFUs. (Incorporate existing visualization
tools whenever possible).
– At the end of the day, our priorities MUST be for
data visualization and analysis of JWST MIRI
and NIRSpec IFU data products. (But we hope
our efforts will be useful for others).
STScI IFU Development
• For the first time, in FY11 I officially have a
small allotment (10%) of my functional work
time dedicated to IFU development.
• Plan of action:
– Create an internal “STScI IFU Working Group” (meet ~1x per
month – first meeting was in Nov. 2010).
– Work with STScI developers, get familiar with 3-D datasets and
3-D .fits structures, existing cube viewing/manipulation tools.
– Work to develop our STScI requirements on IFU datacube
viewing and analysis tools.
– Complete an exercise similar to ESO – identify an existing tool
that we might be able to expand upon and develop.