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SQM-ISS is a detector that will search from the International Space Station for massive particles possibly present among the cosmic rays. Among them, we mention strange quark matter, Q-Balls, lumps of fermionic exotic compact stars, Primordial Black Holes, mirror matter, Fermi balls, etc. These compact, dense objects would be much heavier than normal nuclei, have velocities of galaxy-bound systems, and would be deeply penetrating. The detector is based on a stack of scintillator and piezoelectric elements which can provide information on both the charge state and mass, with the additional timing information allowing to determine the speed of the particle, searching for particles with velocities of the order of galactic rotation speed (v ≲ 250 km/s). In this work, we describe the apparatus and its observational capabilities. [ABSTRACT FROM AUTHOR]

A characterization of the Galactic Cosmic Ray (GCR) induced radiation environment on-board Columbus and the International Space Station (ISS) has been carried out using the Geant4 Monte Carlo particle transport toolkit and detailed geometry models of Columbus and ISS. Dose and dose equivalent rates, as well as penetrating particle spectra are presented. Simulation results indicate that the major part of the dose rates due to GCR protons are associated with secondary particles produced in the hull of ISS. Neutrons contribute about 15% of the GCR proton dose equivalent rate and mesons about 10%. More than 40% of the simulated GCR proton dose and dose equivalent rates are due to protons in the energy range above 10 GeV. Protons in the energy range above 50 GeV contribute only 5% to the dose rates. The total simulated dose and dose equivalent rates at solar maximum are 63 μGy/d and 123 μSv/d, respectively. The dose equivalent rate underestimates measurements made during the 2001 solar maximum. The discrepancy can be attributed to deficiencies in hadronic ion-nuclei interaction models for heavy ions and to the lack of such models above 10 GeV/N in Geant4. [ABSTRACT FROM AUTHOR]

A detailed characterization of the trapped-proton-induced radiation environment on board Columbus and the Inter- national Space Station (ISS) has been carried out using the Geant4 Monte Carlo particle transport toolkit. Dose and dose equivalent rates, as well as penetrating particle spectra are presented. These results are based on detailed Geant4 geometry models of Columbus and ISS, comprising a total of about 1000 geometry volumes. Simulated trapped-proton dose rates are found to be strongly dependent on ISS altitude. Dose rates for different locations inside the Columbus cabin are presented, as well as for different models of the incident trapped-proton flux. Dose rates resulting from incident anisotropic trapped protons are found to be lower than, or equal to, those of omnidirectional models. The anisotropy induced by the asymmetric shielding distribution of Columbus/ISS is also studied. The simulated trapped-proton dose (equivalent) rates, averaged over different locations inside Columbus, are 120 µGy/d (154 µSv/d) and 79 µGy/d (102 µSv/d) for solar minimum and maximum conditions according to AP8 incident proton spectra and an ISS orbit of 380 km. The solar maximum dose rates are found to be of the same order as measurements in other modules in the present ISS. [ABSTRACT FROM AUTHOR]

The Dose Estimation by Simulation of the ISS Radiation Environment (DESIRE) project aims to accurately calculate radiation fluxes and doses to astronauts inside the European Columbus module of the International Space Station using Geant4. Since Geant4 has not been previously used for this type of application it needs to be validated. This will be followed by a detailed evaluation of the incident radiation fields on ISS and culminate with the geometry modeling and full-scale flux and dose simulations for Columbus. Geant4 validation studies and comparisons to other tools are presented. These concern the angle and energy distributions of particles leaving irradiated targets and of energy depositions in the targets. Comparisons are made between simulations using different Geant4 physics models, experimental data, and other particle transport programs. Geant4 using the "Binary Cascade" model for inelastic nucleon reactions performs very well in these comparisons, but some issues with other models remain to be resolved if they are to be used for space radiation shielding applications. Results of Geant4 simulations of the transport of some relevant radiation field components through the hull of a simplified model of Columbus are also presented. [ABSTRACT FROM AUTHOR]