Biomedical subjects

M Leicher

Publications and source records attributed to M Leicher.

6 recordsLinked to original sources

PubMed1999

Energy spectra of geomagnetically trapped oxygen ions.

In a series of COSMOS satellite flights plastic nuclear track detectors have been exposed in low-earth orbits to monitor anomalous cosmic rays (ACR) at energies below 25 MeV/nuc. The analysis of energy spectra has now been extended to energies up to 40 MeV/nuc for two exposures aboard COSMOS 2260 in 1993 and COSMOS 2311 in 1995. Our data on trapped ACR (TACR) oxygen energy spectra might indicate the influence of energy-dependent stripping probabilities and the presence of multiply charged ACR oxygen at high energies as reported by latest SAMPEX observations.

Cosmic Radiation↗

PubMed1998

Results of dosimetric measurements in space missions.

Detector packages consisting of plastic nuclear track detectors, nuclear emulsions, and theromoluminescence detectors were exposed at different locations inside the space laboratory Spacelab and at the astronauts' body and in different sections of the MIR space station. Total dose, particle fluence rate and linear energy transfer (LET) spectra of heavy ions, number of nuclear disintegrations and fast neutron fluence rates were determined of each exposure. The dose equivalent received by the Payload specialists (PSs) were calculated from the measurements, they range from 190 microSv d-1 to 770 microSv d-1. Finally, a preliminary investigation of results from a particle telescope of two silicon detectors, first used in the last BIORACK mission on STS 76, is reported.

Cosmic Radiation↗

PubMed1997

Results of dosimetric measurements in space missions.

Detector packages consisting of thermoluminescence detectors (TLDs), nuclear emulsions and plastic nuclear track detectors were exposed in different locations inside spacecraft. The detector systems, which supplement each other in their registration characteristics, allow the recording of biologically relevant portions of the radiation field independently. Results are presented and compared with calculations. Dose equivalents for the astronauts have been calculated based on the measurements; they lie between 190 microSv d-1 and 860 microSv d-1.

Astronauts↗

PubMed1996

Dosimetric mapping in BIORACK on IML2.

Seven detector packages consisting of plastic nuclear track detectors, nuclear emulsions and thermoluminescence dosimeters were exposed in different locations inside BIORACK during the IML2 mission. The detectors supplement each other in their registration characteristics and cover well the different contributions of the space radiations to the dose. In this report, results are given on total dose measurements, cosmic ray flux and neutron dose. Total doses differ by up to a factor of 1.5 and heavy ion fluxes by more than a factor of 6 in the different locations. The results are compared with those of previous missions. The mission equivalent dose for the astronauts was calculated from the measurements to be 3.8 mSv.

Cosmic Radiation↗

PubMed1996

Dosimetry on the Spacelab missions IML1 and IML2, and D2 and on MIR.

Detector packages consisting of plastic nuclear track detectors, nuclear emulsions, and thermoluminescence detectors were exposed inside BIORACK during the Spacelab missions IML1 and IML2, in different sections of the MIR space station, and inside the Spacelab module at rack front panels or stowage lockers and in the Spacelab tunnel during D2. In addition, during D2, each Payload Specialist (PS) has worn three permanent detector packages; one at the neck; one at the waist; and one at the ankle. Total dose measurements, particle fluence rate and LET spectra, number of nuclear disintegrations and neutron dose from this exposure are given in this report. The results are compared to theoretical calculations and to previous missions results. The dose equivalent (total radiation exposure) received by the PSs were calculated from the measurements and range from 190 to 770 microSv d-1. Finally, a cursory investigation of results from a particle telescope from two silicon detectors, first used in the last BIORACK mission on STS76, is reported.

Atlantic Ocean↗

PubMedDate not supplied

Dosimetric measurements in manned missions.

Detector packages consisting of thermoluminescence detectors (TLDs), nuclear emulsions and plastic nuclear track detectors were exposed in different sections of the MIR space station, inside the Spacelab during the IML1 mission, and inside Spacelab module and tunnel during the D2 mission. This report concentrates on total dose measurements with TLDs during these mission. The results are discussed and compared to results of former missions and to calculations. Finally, dose equivalents and mean quality factors for each mission are presented which are derived from the TLD results and results obtained from the other detector systems. Dose equivalents range between 200 microSvd-1 and 700 microSvd-1.

Aerospace Medicine↗