Steven Jon Stochaj

The Absolute Flux of Protons and Helium at the Top of the Atmosphere Using IMAX

The cosmic-ray proton and helium spectra from 0.2 GeV nucleon^(-1) to about 200 GeV nucleon^(-1) have been measured with the balloon-borne experiment Isotope Matter-Antimatter Experiment (IMAX) launched from Lynn Lake, Manitoba, Canada, in 1992. IMAX was designed to search for antiprotons and light isotopes using a superconducting magnet spectrometer together with scintillators, a time-of-flight system, and Cherenkov detectors. Using redundant detectors, an extensive examination of the instrument efficiency was carried out. We present here the absolute spectra of protons and helium corrected to the top of the atmosphere and to interstellar space. If demodulated with a solar modulation parameter of Φ = 750 MV, the measured interstellar spectra between 20 and 200 GV can be represented by a power law in rigidity, with (1.42 ± 0.21) × 10^4R^(-2.71±0.04) (m^2 GV s sr)^(-1) for protons and (3.15 ± 1.03) × 10^3R^(-2.79±0.08) (m^2 GV s sr)^(-1) for helium.

Performance of a balloon-borne magnet spectrometer for cosmic ray studies

Abstract This paper summarizes the performance characteristics of the balloon-borne magnet spectrometer operated by New Mexico State Universitys Particle Astrophysics Laboratory. Particular emphasis has been placed on the rigidity resolution, including both random and systematic errors of the magnetic spectrometer system. Measurement of the performance characteristics has been greatly enhanced through the use of an imaging calorimeter as an independent aid in the identification of cosmic rays.

Performance of drift chambers in a magnetic rigidity spectrometer for measuring the cosmic radiation

A drift chamber tracking system was developed and flown as part of the IMAX balloon-borne magnetic spectrometer. The drift chamber uses a hexagonal drift-cell structure and is filled with pure CO2 gas. It operated with high efficiency in the strong and inhomogenous field of a superconducting magnet, demonstrating a spatial resolution of better than 100 μm over most of the drift path for singly charged particles, as well as for helium and lithium nuclei. The drift chamber portion of the spectrometer achieved a maximum detectable rigidity of 175 and 250 GV/c for protons and helium respectively.

A measurement of cosmic ray deuterium from 0.5–2.9 GeV/nucleon

The rare isotopes ^(2)H and ^(3)He in cosmic rays are believed to originate mainly from the interaction of high energy protons and helium with the galactic interstellar medium. The unique propagation history of these rare isotopes provides important constraints on galactic cosmic ray source spectra and on models for their propagation within the Galaxy. Hydrogen and helium isotopes were measured with the balloon-borne experiment, IMAX, which flew from Lynn Lake, Manitoba in 1992. The energy spectrum of deuterium between 0.5 and 3.2 GeV/nucleon measured by the IMAX experiment as well as previously published results of ^(3)He from the same instrument will be compared with predictions of cosmic ray galactic propagation models. The observed composition of the light isotopes is found to be generally consistent with the predictions of the standard Leaky Box Model derived to fit observations of heavier nuclei

Formation Flying of a Two-CubeSat Virtual Telescope in a Highly Elliptical Orbit

Relevance: This topic is exclusively about space operations and many aspects of it. It is of broad interest to everyone at the conference. Innovation: This topic is totally innovative, changes the whole game of space operations. Substance: This topic is very important to all programs and projects in most agencies. It is very substantial. Future: This topic is totally focused on enabling new space operations approaches for future programs and projects for most of all agencies.

Maximizing the information content in thin calorimeters for space and balloon applications

Features of the hadronic interactions of cosmic ray particles that make it difficult to measure their energies and identities precisely also provide tools by which these limitations can be partially overcome, if the detector in question is properly instrumented. I review a growing body of experimental and theoretical work to demonstrate methods by which calorimetry of cosmic rays using thin calorimeters may be optimized, and performance improved, by the use of multiple methods to read out the energy deposited by the developing shower. Examples are given using scintillating fiber, Cherenkov readout of quartz optical fiber, and silicon dE/dx information.