7’; fl, pno, perc.

Fragments was composed as both a direct musical interpretation of the physical events of the Chicago Pile- 1 Experiment, but also as a reflection on the natural order (and manipulation) of the chemical elements of our world. Pile-1 worked by firing neutrons at a large quantity of natural uranium, causing the uranium atoms to absorb free neutrons and fission into smaller particles. I first calculated the frequencies of a neutron and Uranium using the Compton wavelength equation in conjunction with the speed of light equation, where one can derive the equation for something’s frequency with respect to its mass. After some research, I found that when Uranium fissions, the most probable particles have atomic mass numbers of 95 and 137, with mass numbers as low as 72, as high as 154, and with an average of 118. All of the pitches corresponding to the 5 fission particles were rounded to the nearest chromatic pitch. The last calculation I needed was the pitch corresponding to Cadmium, as Pile-1 used Cadmium rods to absorb free neutrons and to essentially turn the experiment off. To further establish when the piece uses each of these pitches, I concentrated on their harmonic series. Fragments begins with an exploration of the harmonic series of Uranium’s pitch, and after an introduction of neutrons firing, bursting bell-like chords appear in progression, and the Uranium fissions and fragments. The piece focuses on the two most probable fragment particles, and ends with the introduction of the Cadmium rods.

*Commissioned by the University of Chicago for the 75th Commemoration of the Chicago Pile-1 Nuclear Reactor.*

Premiere: December 2, 2017 by Emma Hospelhorn (fl), John Corkill (perc), and Daniel Pesca (pno) at the University of Chicago.

Honors

Association for the Promotion of New Music Call for Scores winner, 2018.