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91.
A.B. Akopova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1998,21(12):1809-1812
We propose to study the radiation environment on board different flight vehicles: cosmos-type satellites, orbital stations, Space Shuttles and civil (sonic and supersonic) aircraft. These investigations will be carried out with single type of passive detector, namely, nuclear photoemulsions (NPE) with adjustable threshold of particle detection within broad range of linear energy transfer (LET) that is done by means of the technique of selective development of NPE exposed in space.
These investigations will allow one to determine:
- • integral spectra of LET of charged particles of cosmic ray (CR) over a wide range from 2.0 to 5×104 MeV/cm in biological tissue;
• differential energy spectra of fast neutrons (1–20 MeV);
• estimation of absorbed and equivalent doses from charged and neutral component CR;
• charge and energy spectra of low energy nuclei (E≤100 MeV) with Z≥2 having in view the extreme hazard radiation to biological objects and microelectronic schemes taken on board inside and outside of these different flight vehicles with exposures from several days to several months.
The investigation of radiation environment on board the airplanes depending on the flight parameters will be conducted using emulsions of different sensitivity without any controlling of threshold sensitivity (Akopova et al., 1996). The proposed detector can be used in the joint experiments on the new International Cosmic Station “Alpha”. 相似文献
92.
P. Bühler L. Desorgher A. Zehnder E. Daly L. Adams 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1998,21(12):1645-1649
Measurements of the South Atlantic Anomaly (SAA) made with the Radiation Environment Monitor (REM) aboard Mir from November 1994 to February 1996 are presented. During this period an increase of the SAA radiation by ≈25% is observed, which coincides with a lowering of the radio solar flux. Radio solar flux is one of the parameters controlling the earth's atmospheric distribution and with it the absorption of inner radiation belt protons forming the SAA. Due to the altitude gradient of the atmospheric density, the proton fluxes in the SAA are anisotropic (loss cone, east-west effect). The measured distribution can be accounted for by basic models. 相似文献
93.
G.I. Pugacheva D.M. Boscher A.A. Gusev I.M. Martin W.N. Spjeldvik 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2000,25(12):2323-2326
The resulting L-distributions and energy spectra of energetic magnetospheric electrons obtained from numerical solution of the radiation belt transport equation with and without accounting for electron synchrotron energy losses are compared. It is demonstrated that synchrotron losses play an important role in formation of the space and energetic distributions of electrons in the inner magnetosphere. 相似文献
94.
V Bidoli M Casolino M P De Pascale G Furano A Morselli L Narici P Picozza E Reali R Sparvoli A M Galper A V Ozerov YuV "Y ">Popov N R Vavilov A P Alexandrov S V Avdeev Y u Baturin Y u Budarin G Padalko V G Shabelnikov G Barbellini W Bonvicini A Vacchi N Zampa S Bartalucci G Mazzenga M Ricci O Adriani P Spillantini M Boezio P Carlson C Fuglesang G Castellini W G Sannita 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2000,25(10):2075-2079
The SilEye experiment aims to study the cause and processes related to the anomalous Light Flashes (LF) perceived by astronauts in orbit and their relation with Cosmic Rays. These observations will be also useful in the study of the long duration manned space flight environment. Two PC-driven silicon detector telescopes have been built and placed aboard Space Station MIR. SilEye-1 was launched in 1995 and provided particles track and LF information; the data gathered indicate a linear dependence of FLF(Hz) ( 4 2) 10(3) 5.3 1.7 10(4) Fpart(Hz) if South Atlantic Anomaly fluxes are not included. Even though higher statistic is required, this is an indication that heavy ion interactions with the eye are the main LF cause. To improve quality and quantity of measurements, a second apparatus, SilEye-2, was placed on MIR in 1997, and started work from August 1998. This instrument provides energetic information, which allows nuclear identification in selected energy ranges; we present preliminary measurements of the radiation field inside MIR performed with SilEye-2 detector in June 1998. 相似文献
95.
P A Craven M J Rycroft 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1996,18(1-2):45-49
Beyond the magnetic influence of the Earth, the flux of galactic cosmic radiation (GCR) represents a radiological concern for long-term manned space missions. Current concepts of radiation quality and equivalent dose are inadequate for accurately specifying the relative biological \"efficiency\" of low doses of such heavily ionising radiations, based as they are on the single parameter of Linear Energy Transfer (LET). Such methods take no account of the mechanisms, nor of the highly inhomogeneous spatial structure, of energy deposition in radiation tracks. DNA damage in the cell nucleus, which ultimately leads to the death or transformation of the cell, is usually initiated by electrons liberated from surrounding molecules by the incident projectile ion. The characteristics of these emitted \"delta-rays\", dependent primarily upon the charge and velocity of the ion, are considered in relation to an idealised representation of the cellular environment. Theoretically calculated delta-ray energy spectra are multiplied by a series of weighting algorithms designed to represent the potential for DNA insult in this environment, both in terms of the quantity and quality of damage. By evaluating the resulting curves, and taking into account the energy spectra of heavy ions in space, a relative measure of the biological relevance of the most abundant GCR species is obtained, behind several shielding configurations. It is hoped that this method of assessing the radiation quality of galactic cosmic rays will be of value when considering the safety of long-term manned space missions. 相似文献
96.
A.C. Levasseur-Regourd 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1996,17(12):117-122
In-situ space observations of dust in the solar system are seldom possible. On the opposite, remote observations of solar light scattered by dust are relatively easy to perform from Earth- or satellite-based observatories; the evolution of the polarization of light scattered by dust particles as a function of the phase angle may provide information on the physical properties of these particles. Unfortunately, since remote observations are integrated along the line-of-sight of the observer, they can hardly be used to determine local physical properties. We have precisely developed Optical Probe techniques to forge the link between the numerous remote observations and the unique in-situ measurements. A short review of the remote observations of light scattered by cometary dust is first presented. Then, the Optical Probe concept is analyzed. Finally, the OPE instrument, which had been designed to optically probe the inner coma of comet Halley is described; its limitations and its achievements during Halley and Grigg-Skjellerup encounters are discussed. 相似文献
97.
98.
J. P. Cox J. C. Wheeler C. J. Hansen D. S. King A. N. Cox S. W. Hodson 《Space Science Reviews》1980,27(3-4):529-535
The radial pulsations of very luminous, low-mass models (L/M 104, solar units), which are possible representatives of the R CrB stars, have been examined. These pulsations are extremely nonadiabatic. We find that there are in some cases at least one extra (strange) mode which makes interpretation difficult. The blue instability edges are also peculiar, in that there is an abrupt excursion of the blue edge to the blue for L/M sufficiently large. The range of periods of the model encompasses observed periods of the Cepheid-like pulsations of actual R CrB stars. 相似文献
99.
J.L. Hall D. Fairbrother T. Frederickson V.V. Kerzhanovich M. Said C. Sandy J. Ware C. Willey A.H. Yavrouian 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
This paper describes the design, fabrication and testing of a full scale prototype balloon intended for long duration flight in the upper atmosphere of Venus. The balloon is 5.5 m in diameter and is designed to carry a 45 kg payload at an altitude of 55 km. The balloon material is a 180 g/m2 multi-component laminate comprised of the following layers bonded together from outside to inside: aluminized Teflon film, aluminized Mylar film, Vectran fabric and a polyurethane coating. This construction provides the required balloon functional characteristics of low gas permeability, sulfuric acid resistance and high strength for superpressure operation. The design burst superpressure is 39,200 Pa which is predicted to be 3.3 times the worst case value expected during flight at the highest solar irradiance in the mission profile. The prototype is constructed from 16 gores with bi-taped seams employing a sulfuric acid resistant adhesive on the outside. Material coupon tests were performed to evaluate the optical and mechanical characteristics of the laminate. These were followed by full prototype tests for inflation, leakage and sulfuric acid tolerance. The results confirmed the suitability of this balloon design for use at Venus in a long duration mission. The various data are presented and the implications for mission design and operation are discussed. 相似文献
100.
We describe the results of determining the mass of the International Space Station using the data of MAMS accelerometer taken during correction of the station orbit on August 20, 2004. The correction was made by approach and attitude control engines (ACE) of the Progress transporting spacecraft. The engines were preliminary calibrated in an autonomous flight using the onboard device for measuring apparent velocity increment. The method of calibration is described and its results are presented. The error in station mass determination is about 1%. The same data of MAMS and similar data obtained during the orbit correction on August 26, 2004 were used for the analysis of high-frequency vibrations of the station mainframe caused by operation of the ACE of Progress. Natural frequencies of the ACE are determined. They lie in the frequency band 0.024–0.11 Hz. ACE operation is demonstrated to result in a substantial increase of microaccelerations onboard the station in the frequency range 0–1 Hz. The frequencies are indicated at which disturbances increase by more than an order of magnitude. The study described was carried out as a part of the Tensor technological experiment. 相似文献