Solar cycle variations of MIR radiation environment as observed by the LIULIN dosimeter
View/ Open
Authors
Dachev, T.P.
Tomov, B.T.
Matviichuk, Y.N.
Koleva, R.T.
Semkova, J.V.
Petrov, V.M.
Benghin, V.V.
Ivanov, Y.V.
Shurshakov, V.A.
Lemaire, J.F.
Discipline
Physical sciences
Subject
Approximation theory
Atmospheric temperature
Cosmic rays
Dosimeters
Dosimetry
Protons
Silicon sensors
Space flight
Space stations
Dose rate
Galactic cosmic rays
Particle fluxes
Solar cycle variations
Total neutral density
Solar radiation
article
Atlantic Ocean
atmosphere
chemistry
cosmic radiation
Flight Experiment
instrumentation
long duration
manned
Mir Project
radiation dose
radiation monitoring
radiometry
solar energy
South America
space flight
theoretical model
weightlessness
Flight Experiment
long duration
manned
Mir Project
Atlantic Ocean
Atmosphere
Cosmic Radiation
Models, Theoretical
Radiation Dosage
Radiation Monitoring
Radiometry
Solar Activity
South America
Space Flight
Spacecraft
Weightlessness
Audience
Scientific
Date
1999Metadata
Show full item recordDescription
Measurements on board the MIR space station by the Bulgarian-Russian dosimeter LIULIN have been used to study the solar cycle variations of the radiation environment. The fixed locations of the instrument in the MIR manned compartment behind 6-15 g/cm 2 of shielding have given homogeneous series of particle fluxes and doses measurements to be collected during the declining phase of 22nd solar cycle between September 1989 and April 1994. During the declining phase of 22nd solar cycle the GCR (Galactic Cosmic Rays) flux observed at L > 4 (where L is the McIlwain parameter) has enhanced from 0.6-0.7 cm -2 s -1 up to 1.4-1.6 cm -2 s -1. The long-term observations of the trapped radiation can be summarized as follows: the main maximum of the flux and dose rate is located at the southeast side of the geomagnetic field minimum of South Atlantic Anomaly (SAA) at L = 1.3-1.4. Protons depositing few (nGy cm 2)/particle in the detector predominantly populate this region. At practically the same spatial location and for similar conditions the dose rate rises up from 480 to 1470 μGy/h dose in silicon in the 1990-1994 time interval, during the declining phase of the solar cycle. On the other hand the flux rises from 35 up to 115 cm -2 s -1 for the same period of time. A power law dependence was extracted which predicts that when the total neutral density at the altitude of the station decreases from 8 × 10 -15 to 6 × 10 -16 g/cm 3 the dose increase from about 200 μGy/h up to 1200 μGy/h. At the same time the flux increase from about 30 cm -2 s -1 up to 120 cm -2 s -1. The AP8 model predictions give only 5.8% increase of the flux for the same conditions.
Citation
Dachev, T.P.; Tomov, B.T.; Matviichuk, Y.N.; Koleva, R.T.; Semkova, J.V.; Petrov, V.M.; Benghin, V.V.; Ivanov, Y.V.; Shurshakov, V.A.; Lemaire, J.F. (1999). Solar cycle variations of MIR radiation environment as observed by the LIULIN dosimeter. , Radiation Measurements, Vol. 30, Issue 3, 269-274, DOI: 10.1016/S1350-4487(99)00061-X.Identifiers
scopus: 2-s2.0-0033237357
Type
Article
Peer-Review
Yes
Language
eng