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[Results of measuring the charge and energy spectra of heavy nuclei on board the artificial Earth satellite Kosmos-936].

The measurements were performed using a package of dielectric track detectors mounted behind the shield of 60-80 kg.m-2 thick. The charge of nuclei was determined from the complete track length. As a result, 1915 tracks of nuclei with Z greater than or equal to 6 in the energy range 100-450 MeV/nuclon were detected and identified. The differential charge spectrum of nuclei with 6 less than or equal to Z less than or equal to 28 and the energy spectrum of nuclei of the iron group were built. For iron nuclei the following ration of isotope groups was obtained: (Fe52 + Fe53 + Fe54): (Fe55 + Fe56 + Fe57) : (Fe58 + Fe59 + Fe60) = (0.30 +/- 0.08) = (0.49 +/- 0.10) : (0.21 +/- 0.05).

Cosmic Radiation↗
PubMed1982

[Model calculations of the Energy distribution of scattered radiation in a patient (author's transl)].

To obtain quantitative results on scattered radiation produced in a patient by externally applied x-rays or gamma rays, the model of a pencil beam penetrating a water layer is used. By means of the Monte-Carlo method, the energy distribution of scattered photons in a plane parallel to the absorbing layer is calculated for primary photon energies from 60 to 1250 keV. This yields information on the distribution of single-scatter and multiple-scatter photons.

Elementary Particles↗
PubMed1980

Tissue reaction & tumor response with negative pi mesons.

As a prelude to a randomized trial of negative pi meson (pion) radiotherapy, as compared to conventional radiation treatment, tolerance of several normal tissues was investigated. Fifty-three of 108 patients received at least 2700 peak pion rads at a usual dose rate between 100 and 125 rads daily. The major sites treated were head and neck, pancreas, prostate, rectum and brain. Acute normal tissue reactions, late effects, and tumor response are correlated with the two dose levels. Pancreatic tumors have not fared well. At this point, tumors that can be observed disappear more rapidly, and, for tumors that cannot be observed, symptoms disappear more rapidly and normal tissues exhibit less reaction than with conventional radiotherapy. It is believed that the dose level can be raised an additional 7 percent above the current 4100 rads, measured at the maximum within the treatment volume.

Elementary Particles↗
PubMed1980

Radiobiologic properties of pions and heavy ions. A comparison.

1. Depth-dosage distributions of pions and heavy ions are similar, but the dose fall-off near the range is much steeper for heavy ions compared to pions. 2. Radiation quality and hence biologic effects of heavy ion beams in the peak region depend only on peak width, whereas for pion beams because of fast neutrons from stars, the radiation quality may depend not only on peak width but also on beam size. 3. For neon and argon ions, the biologic effects of fractionated doses in proliferating cells are found to be more effective than for single doses. Such an effect was not observed for either fast neutrons or for pions. 4. Radiobiologically, pion beams are similar to helium and carbon ions.

Animals↗