ALBERT

Description: A tissue equivalent proportional counter designed to measure the linear energy transfer spectra (LET) in the range 0.2-1250 keV/micrometer was flown in the Kvant module on the Mir orbital station during September 1994. The spacecraft was in a 51.65 degrees inclination, elliptical (390 x 402 km) orbit. This is nearly the lower limit of its flight altitude. The total absorbed dose rate measured was 411.3 +/- 4.41 microGy/day with an average quality factor of 2.44. The galactic cosmic radiation (GCR) dose rate was 133.6 microGy/day with a quality factor of 3.35. The trapped radiation belt dose rate was 277.7 microGy/day with an average quality factor of 1.94. The peak rate through the South Atlantic Anomaly was approximately 12 microGy/min and nearly constant from one pass to another. A detailed comparison of the measured LET spectra has been made with radiation transport models. The GCR results are in good agreement with model calculations; however, this is not the case for radiation belt particles and again points to the need for improving the AP8 omni-directional trapped proton models.

Description: Described is the Liulin-5 experiment and instrumentation, developed for investigation of the space radiation doses depth distribution in a human phantom on the Russian Segment of the International Space Station (ISS). Liulin-5 experiment is a part of the international project MATROSHKA-R on ISS. The experiment MATROSHKA-R is aimed to study the depth dose distribution at the sites of critical organs of the human body, using models of human body-anthropomorphic and spherical tissue-equivalent phantoms. The aim of Liulin-5 experiment is long term (4-5 years) investigation of the radiation environment dynamics inside the spherical tissue-equivalent phantom, mounted in different places of the Russian Segment of ISS. Energy deposition spectra, linear energy transfer spectra, flux and dose rates for protons and the biologically-relevant heavy ion components of the galactic cosmic radiation will be measured simultaneously with near real time resolution at different depths of the phantom by a telescope of silicon detectors. Data obtained together with data from other active and passive dosimeters will be used to estimate the radiation risk to the crewmembers, verify the models of radiation environment in low Earth orbit, validate body transport model and correlate organ level dose to skin dose. Presented are the test results of the prototype unit. The spherical phantom will be flown on the ISS in 2004 year and Liulin-5 experiment is planned for 2005 year. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

Description: Liulin, a dosimetry-radiometry system, was developed to satisfy the requirements for active flux and dose rate measurements for the flight of the second Bulgarian cosmonaut in 1988. The system consists of a compact battery-operated silicon solid state detector unit and a read/write microcomputer and telemetry unit. We describe the pre-flight calibrations with charged particles, using radioactive sources and accelerated 170 MeV/nucleon proton and alpha particles at the Dubna, Russia cyclotron. We discuss comparisons with data obtained on Mir with the French-built tissue equivalent LET spectrometer NAUSICAA. Lastly, we describe post-flight calibrations performed with 1 GeV/nucleon 56Fe ions at the Brookhaven National Laboratory AGS accelerator, where the instrument was mounted in tandem with several thin position-sensitive silicon detectors behind a stopping target. The silicon detectors provided an energy spectrum for the surviving charged nuclear fragments for which the flux and absorbed dose were recorded by Liulin.

Description: The Altcriss project aims to perform a long term survey of the radiation environment on board the International Space Station. Measurements are being performed with active and passive devices in different locations and orientations of the Russian segment of the station. The goal is perform a detailed evaluation of the differences in particle fluence and nuclear composition due to different shielding material and attitude of the station. The Sileye-3/Alteino detector is used to identify nuclei up to Iron in the energy range above approximately equal to 60 MeV/n; a number of passive dosimeters (TLDs, CR39) are also placed in the same location of Sileye-3 detector. Polyethylene shielding is periodically interposed in front of the detectors to evaluate the effectiveness of shielding on the nuclear component of the cosmic radiation. The project was submitted to ESA in reply to the AO the Life and Physical Science of 2004 and was begun in December 2005. Dosimeters and data cards are rotated every six months: up to now three launches of dosimeters and data cards have been performed and have been returned with the end expedition 12 and 13.

Description: Flux transfer events (FTEs) are common on the Earth's dayside low- and mid-latitude magnetopause, where they tend to occur for southward interplanetary magnetic field (IMF) orientations. "Direct" events exhibiting (+,-) bipolar signatures normal to the nominal magnetopause predominate at northern latitudes, whereas reverse events exhibiting (-,+) bipolar signatures normal to the nominal magnetopause predominate at southern latitudes. This paper reports Interball-1 magnetometer observations of reverse events on the high-latitude northern magnetopause and direct events on the high-latitude southern magnetopause. During one sequence of events, the sense of the bipolar signature normal to the nominal magnetopause reversed. In conjunction with the fact that most events occur when and where magnetosheath and magnetospheric magnetic field lie nearly antiparallel, the observations suggest that lobe events are generated locally on the high-latitude magnetopause.

Description: A joint investigation between the United States and Russia to study the radiation environment inside the Space Shuttle flight STS-60 was carried out as part of the Shuttle-Mir Science Program (Phase 1). This is the first direct comparison of a number of different dosimetric measurement techniques between the two countries. STS-60 was launched on 3 February 1994 in a nearly circular 57 degrees x 353 km orbit with five U.S. astronauts and one Russian cosmonaut for 8.3 days. A variety of instruments provided crew radiation exposure, absorbed doses at fixed locations, neutron fluence and dose equivalent, linear energy transfer (LET) spectra of trapped and galactic cosmic radiation, and energy spectra and angular distribution of trapped protons. In general, there is good agreement between the U.S. and Russian measurements. The AP8 Min trapped proton model predicts an average of 1.8 times the measured absorbed dose. The average quality factor determined from measured lineal energy, y, spectra using a tissue equivalent proportional counter (TEPC), is in good agreement with that derived from the high temperature peak in the 6LiF thermoluminescent detectors (TLDs). The radiation exposure in the mid-deck locker from neutrons below 1 MeV was 2.53 +/- 1.33 microSv/day. The absorbed dose rates measured using a tissue equivalent proportional counter, were 171.1 +/- 0.4 and 127.4 +/- 0.4 microGy/day for trapped particles and galactic cosmic rays, respectively. The combined dose rate of 298.5 +/- 0.82 microGy/day is about a factor of 1.4 higher than that measured using TLDs. The westward longitude drift of the South Atlantic Anomaly (SAA) is estimated to be 0.22 +/- 0.02 degrees/y. We evaluated the effects of spacecraft attitudes on TEPC dose rates due to the highly anisotropic low-earth orbit proton environment. Changes in spacecraft attitude resulted in dose-rate variations by factors of up to 2 at the location of the TEPC.

Description: The LIULIN-3M instrument is a further development of the LIULIN dosimeter-radiometer, which has been used on the NffR space station in the 1988-1994 time period, The LIULIN-3M is designed for continuous monitoring of the radiation environment during the BION-12 satellite flight in 1999. A semiconductor detector with 1 mm thickness and 1 cm(exp 2) area is used in the instrument. Pulse high analysis technique is used for measurement of the energy losses in the detector. The final data sets from the instrument are the flux and the dose rate for the exposition time and 256 channels of LET spectra if a non-nal coincidence of the particles to the detector is considered. The LIULIN-3M instrument was calibrated by proton fluxes with different energies at the Indiana University Cyclotron Facility in June 1997 and was used for space radiation measurements during commercial aircraft flights. Obtained calibration and flight results are analyzed in the paper.