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I Apathy

Publications and source records attributed to I Apathy.

6 recordsLinked to original sources

Personal dosimetry for human missions to Mars based on TLD and LET-spectrometry technique.

Exposure of crew to the space radiation environment poses one of the most significant problems in long term missions in low earth orbits and in interplanetary missions. Accurate personal dose measurement will become increasingly important especially during manned missions to Mars. A series of instruments suitable for on-board dose, flux and LET measurements has been developed by the authors'. Based on the experience gained so far from their utilization, an instrument consisting of a thermoluminescent device and a dosimetry telescope is proposed for the use on the International Space Station and for human Mars missions. The short technical description of this instrument is given in this paper.

Humans↗

Dose measurements in space by the Hungarian Pille TLD system.

Exposure of crew, equipment, and experiments to the ambient space radiation environment in low Earth orbit poses one of the most significant problems to long-term space habitation. Accurate dose measurement has become increasingly important during the assembly (extravehicular activity (EVA)) and operation of space stations such as on Space Station Mir. Passive integrating detector systems such as thermoluminescent dosemeters (TLDs) are commonly used for dosimetry mapping and personal dosimetry on space vehicles. The well-known advantages of passive detector systems are their independence of power supply, small dimensions, high sensitivity, good stability, wide measuring range, resistance to environmental effects, and relatively low cost. Nevertheless, they have the general disadvantage that for evaluation purposes they need a laboratory or large--in mass and power consumption--terrestrial equipment, and consequently they cannot provide time-resolved dose data during long-term space flights. KFKI Atomic Energy Research Institute (KFKI AEKI) has developed and manufactured a series of thermoluminescent dosemeter systems for measuring cosmic radiation doses in the 10 microGy to 10 Gy range, consisting of a set of bulb dosemeters and a compact, self-contained, TLD reader suitable for on-board evaluation of the dosemeters. By means of such a system, highly accurate measurements were carried out on board the Salyut-6, -7 and Mir Space Stations as well as on the Space Shuttle. A detailed description of the system is given and the comprehensive results of these measurements are summarised.

Astronauts↗

An on-board TLD system for dose monitoring on the International Space Station.

This institute has developed and manufactured a series of thermoluminescence dosemeter (TLD) systems for spacecraft, consisting of a set of bulb dosemeters and a small, compact, TLD reader suitable for on-board evaluation of the dosemeters. By means of such a system highly accurate measurements were carried out on board the Salyut-6, -7 and Mir Space Stations as well as on the Space Shuttle. A new implementation of the system will be placed on several segments of the ISS as the contribution of Hungary to this intemational enterprise. The well proven CaSO4:Dy dosemeters will be used for routine dosimetry of the astronauts and in biological experiments. The mean LET value will be measured by LiF dosemeters while doses caused by neutrons are planned to be determined by 6LiF/7LiF dosemeter pairs and moderators. A detailed description of the system is given.

Computer Systems↗

Extra dose due to extravehicular activity during the NASA4 mission measured by an on-board TLD system.

A microprocessor-controlled on-board TLD system, 'Pille'96', was used during the NASA4 (1997) mission to monitor the cosmic radiation dose inside the Mir Space Station and to measure the extra dose to two astronauts in the course of their extravehicular activity (EVA). For the EVA dose measurements, CaSO4:Dy bulb dosemeters were located in specially designed pockets of the ORLAN spacesuits. During an EVA lasting 6 h, the dose ratio inside and outside Mir was measured. During the EVA, Mir crossed the South Atlantic Anomaly (SAA) three times. Taking into account the influence of these three crossings the mean EVA/internal dose rate ratio was 3.2. Internal dose mapping using CaSO4:Dy dosemeters gave mean dose rates ranging from 9.3 to 18.3 microGy h-1 at locations where the shielding effect was not the same. Evaluation results of the high temperature region of LiF dosemeters are given to estimate the mean LET.

Calcium Sulfate↗

Doses due to the South Atlantic Anomaly during the Euromir'95 mission measured by an on-board TLD system.

During the Euromir'95 mission, a specially designed microprocessor-controlled thermoluminescent detector (TLD) system, called the 'Pille'95', was used by ESA astronaut Thomas Reiter to measure the cosmic radiation dose inside the Mir space station. One of the experiment's objectives was to determine the dose fraction on Mir due to the South Atlantic Anomaly (SAA) on an orbit inclined at 51.6 degrees and at an altitude of about 400 km. Using an hourly measuring period for 170 h in automatic mode, dose components both of galactic (independent of SAA) and SAA origin were determined. It was found that the maximum dose due to crossing the SAA was equal to 55 microGy. Averaging all the measurements it was calculated that the mean dose rate inside the Mir was 12-14 microGy h-1 and that half of this value was caused by the SAA.

Astronauts↗

Microprocessor controlled portable TLD system.

An up-to-date microprocessor controlled thermoluminescence dosemeter (TLD) system for environmental and space dose measurements has been developed. The earlier version of the portable TLD system, Pille, was successfully used on Soviet orbital stations as well as on the US Space Shuttle, and for environmental monitoring. The new portable TLD system, Pille'95, consists of a reader and TL bulb dosemeters, and each dosemeter is provided with an EEPROM chip for automatic identification. The glow curve data are digitised and analysed by the program of the reader. The measured data and the identification number appear on the LED display of the reader. Up to several thousand measured data together with the glow curves can be stored on a removable flash memory card. The whole system is supplied either from built-in rechargeable batteries or from the mains of the space station.

Computers↗