CUBISM, The CUbe Builder for IRS Spectra Maps, is a tool for constructing spectral cubes, maps, and arbitrary aperture 1D spectral extractions from sets of mapping mode spectra taken with Spitzer's IRS spectrograph. Developed by the SINGS team to fulfill, in part, its Legacy proposal commitments, CUBISM has been released and is available from the SSC. It is optimized for non-sparse maps of extended objects, e.g. the nearby galaxy sample of SINGS, but can be used with data from any spectral mapping AOR.


The algorithm and design of CUBISM are documented in the following paper:

Spectral Mapping Reconstruction of Extended Sources, J.D.T. Smith et al., 2007, PASP 119, 1133.

Please reference this paper for all scientific uses of CUBISM.


CUBISM is divided into three main components:

Parts of CUBISM derive from JD Smith's thesis work, and elements of SCOREX, a tool written for SCORE, the IRS Short-High Spectrograph proto-type instrument. CUBISM is written in IDL.


July, 2011:
A version of CUBISM (v1.8) compatible with the final IRS reprocessing pipeline (S18.18) has been released.


CUBISM employs a custom flux-conserving algorithm somewhat similar to drizzling to map the partial pixels from overlapping, rotated individual 2D BCD spectra into a single spectral cube with consistent spatial and spectral sampling. A cartoon at right of this process shows how individual pseudo-rectangular regions of constant wavelength (which do not align with the detector array) are clipped and combined together with data from other BCDs on a single sky grid. For the high-resolution modules, orders which overlap in wavelength are combined by clipping individual pixels over more than one wavelength plane in the final cube.


A screenshot showing CUBISM working on the LL radial strip of NGC6946.