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The Gamma Ray Large Area Space Telescope (GLAST) Large Area Telescope (LAT) is a pair-production high-energy (>20 MeV) gamma-ray telescope being built by an international partnership of astrophysicists and particle physicists for a satellite launch in 2006, designed to study a wide variety of high-energy astrophysical phenomena. As part of the development effort, the collaboration has built a Balloon Flight Engineering Model (BFEM) for flight on a high-altitude scientific balloon. The BFEM is approximately the size of one of the 16 GLAST-LAT towers and contains all the components of the full instrument: plastic scintillator anticoincidence system (ACD), high-Z foil/Si strip pair-conversion tracker (TKR), CsI hodoscopic calorimeter (CAL), triggering and data acquisition electronics (DAQ), commanding system, power distribution, telemetry, real-time data display, and ground data processing system. The principal goal of the balloon flight was to demonstrate the performance of this instrument configuration under conditions similar to those expected in orbit. Results from a balloon flight from Palestine, Texas, on August 4, 2001, show that the BFEM successfully obtained gamma-ray data in this high-background environment., To be published in IEEE Transactions on Nuclear Science, Vol 49 Replacement to include an author who was omitted

We consider global transitions from superconducting to normal state of small grains induced by the absorption of energetic (1- 100 keV) photons. Initially the energy is transferred to a single photoelectrons, which loses the energy as it scatters inelastically. To measure the energy of the photon, this collision cascade must be contained within the grain. Reconciling this requirement with the requirement that the dispersed energy must suffice to warm the grain above the transition temperature, leads to estimate of grain sizes and effective operating range of photon energies for various materials and T and H biasing conditions.

Measurements on Copper phthalocyanine iodide Cu(pc)I indicate that this material is an excellent one dimensional conductor with parallel arrays of localized moments that interact strongly with the conduction electrons. The result is an antiferromagnetic indirect interaction between localized spins mediated by the itinerant electrons. A comparison is made between ESR, magnetic susceptibility, and NMR measurements for a number of materials with the phthalocyanine architecture: Ni(pc)I, Cu(pc) and Cu(pc)I.