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Abstract
Over the last twenty years advances in detector technology have transformed infrared astronomy from a curiosity into a valuable tool of modern astronomy. This change also required advancements in three key areas: data acquisition systems, data reduction systems, and the astronomical interpretation of infrared observations.
A data acquisition system based on digital signal processors (DSPs) and capable of accommodating the high throughput of infrared arrays was constructed. By using off-the-shelf components, system design was simplified, construction time and cost were reduced, and reliability was increased. The use of DSPs shifts much of the functionality and development work from hardware to software. The acquisition software is a distributed system running on two Sun SPARCstations and two DSP cards containing Motorola DSP56001s. The data acquisition software takes advantage of the object-oriented features of C++ to modularize the software system. The modularity of this system allows it to be easily adapted to other telescopes and/or arrays.
A general astronomical reduction system was created. The system allows the easily manipulation of three dimensional arrays in mathematical expressions, can automatically process data taken in the common infrared observing modes, and provides a uniquely flexible plotting interface which allows data to be viewed as spectra, contour plots, color images, or as a "movie".
Observations of (NeII) (12.8 $\mu$m), (ArIII) (8.99 $\mu$m), (SIV) (10.51 $\mu$m), and Hydrogen Br$\alpha$ (4.06 $\mu$m) were used to probe the excitation and kinematics within the starburst nucleus of M82. The temperature of the stars ionizing the starburst region is approximately 33,000 K, cooler than most Galactic HII regions. This may be the result of either in initial mass function that does not produce high mass stars or the termination of the starburst $4\times 10\sp6$ years ago. Within the starburst region, the ionized gas is distributed in a nuclear ring and two ionized lanes, structures that are normally associated with galaxies containing nuclear bars. A search of M82's rotation curve for the $x\sb1$ and $x\sb2$ families of orbits commonly found in bars hints at the presence of a bar, but remains inconclusive.
