Postdoc papers
• Arnott, W.P. and J.S. Sabatier, 1990: Laser-Doppler vibrometer measurements of acoustic to seismic coupling. Applied Acoustics, 30 , 279-291.
• Sabatier, J.S., H. Hess, W.P. Arnott, K. Attenborough, M. Romkens and E. Grissinger, 1990: In situ measurements of soil physical properties by acoustical techniques. Soil Sci. Soc. Am. 54 , 658-672.
• Roh, H., W. P. Arnott, J. M. Sabatier and R. Raspet, 1991: Measurement and calculation of acoustic propagation constants in arrays of small air-filled rectangular tubes, J. Acoust. Soc. Am., 89 , 2617-2624.
• Arnott, W.P. H.E. Bass and R. Raspet, 1991: General formulation of thermoacoustics for stacks having arbitrarily-shaped pore cross-sections. J. Acoust. Soc. Am., 90 , 3228-3237. (A key paper for me, and one that was particularly useful to others). Some of the ideas coming out of this time have been realized in a well-used software package for design of acoustic refrigerators and prime movers (sounds sources). (Click here for a better copy of the paper, though it requires a DJVU plugin for your browser).
• Arnott, W. P., J.M. Sabatier and R. Raspet, 1991: Sound propagation in capillary-tube-type porous media with small pores in the capillary walls. J. Acoust. Soc. Am., 90 , 3299-3306. (requires a DJVU plugin for your browser).
• Arnott, W.P., H.E. Bass and R. Raspet, 1992: Specific acoustic impedance measurements of an air-filled thermoacoustic prime mover. J. Acoust. Soc. Am., 92 , 3432.
I had a Postdoc at the University of Mississippi, Physics Department and National Center for Physical Acoustics (NCPA), from 1988-1991. It was a very fruitful experience for me on all fronts. I learned a lot about interfacing with people, and being more open to collaboration, in addition to the specific acoustics research detailed above. NCPA came into existence during my Postdoc, and talented researchers from around the country gathered to study acoustics. The fine building on campus was completed, and a number of interesting advancements were made, including single bubble sonoluminescence by Felipe Gaitan.
I started out working on the coupling of atmospheric sound with ground motion, acoustic to seismic coupling. We did some interesting experiments with low frequency speakers raised on scaffolding, as well as with propane cannons, to investigate how much the ground moves as a function of frequency. One practical advancement from this work is the potential to find land mines by this method. We also measured soil properties using sound; permeability, tortuosity, and porosity were inferred from probe mic and Lloyd's mirror like measurements.
I also did a lot of theory in the area of thermoacoustics, the interaction of heat and sound. The holy grail of this work was the potential of acoustic refrigerators using 'simple' inert gas mixtures as the working fluids instead of ozone-harming chlorofluorocarbons. Some of this work spilled over to my job at the Desert Research Institute. We also made several systems for studying basic thermoacoustic properties of sound sources.
The postdoc research gave me significant skills in theoretical acoustics, and an appreciation for measurement methods that was lacking in my prior research. I also had a chance to teach two courses, Optics and Statistical Mechanics and Thermodynamics, as well as to contribute to the Advanced Acoustics course. I left NCPA well positioned to work at the Desert Research Institute, University of Nevada, and to make substantial contributions especially to the field of aerosol light absorption measurement by photoacoustic methods.
Oxford MS was quite a trip - from Faulkner to James Meredith, from catfish to budweiser, from humidity, green, rain to winter chill, many things were new to me. I made numerous good friends, and thoroughly enjoyed the experience, but was ready to leave in the end, back to the mountains!