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1.
The Advanced Thin Ionization Calorimeter (ATIC) experiment is designed to investigate the charge composition and energy spectra of primary cosmic rays over the energy range from about 1011 to 1014 eV during Long Duration Balloon (LDB) flights from McMurdo, Antarctica. Currently, analysis from the ATIC-1 test flight and ATIC-2 science flight is underway and preparation for a second science flight is in progress. Charge identification of the incident cosmic ray is accomplished, primarily, by a pixilated Silicon Matrix detector located at the very top of the instrument. While it has been shown that the Silicon Matrix detector provides good charge identification even in the presence of electromagnetic shower backscatter from the calorimeter, the detector only measures the charge once. In this paper, we examine use of the top scintillator hodoscope detector to provide a second measure of the cosmic ray charge and, thus, improve the ATIC charge identification.  相似文献   

2.
The Cosmic-Ray Energetics And Mass balloon-borne experiment has been launched twice in Antarctica, first in December 2004 and again in December 2005. It circumnavigated the South Pole three times during the first flight, which set a flight duration record of 42 days. A cumulative duration of 70 days within 13 months was achieved when the second flight completed 28 days during two circumnavigations of the Pole on 13 January 2006. Both the science instrument and support systems functioned extremely well, and a total 117 GB of data including 67 million science events were collected during these two flights. Preliminary analysis indicates that the data extend well above 100 TeV and follow reasonable power laws. The payload recovered from the first flight has been refurbished for the third flight in 2007, whereas the payload from the second flight is being refurbished to be ready for the fourth flight in 2008. Each flight will extend the reach of precise cosmic-ray composition measurements to energies not previously possible.  相似文献   

3.
Development overview of the revised NASA Ultra Long Duration Balloon   总被引:1,自引:0,他引:1  
The desire for longer duration stratospheric flights at constant float altitudes for heavy payloads has been the focus of the development of the National Aeronautics and Space Administration’s (NASA) Ultra Long Duration Balloon (ULDB) effort. Recent efforts have focused on ground testing and analysis to understand the previously observed issue of balloon deployment. A revised approach to the pumpkin balloon design has been tested through ground testing of model balloons and through two test flights. The design approach does not require foreshortening, and will significantly reduce the balloon handling during manufacture reducing the chances of inducing damage to the envelope. Successful ground testing of model balloons lead to the fabrication and test flight of a ∼176,000 m3 (∼6.2 MCF – Million Cubic Foot) balloon. Pre-flight analytical predictions predicted that the proposed flight balloon design to be stable and should fully deploy. This paper provides an overview of this first test flight of the revised Ultra Long Duration Balloon design which was a short domestic test flight from Ft. Sumner, NM, USA. This balloon fully deployed, but developed a leak under pressurization. After an extensive investigation to the cause of the leak, a second test flight balloon was fabricated. This ∼176,000 m3 (∼6.2 MCF) balloon was flown from Kiruna, Sweden in June of 2006. Flight results for both test flights, including flight performance are presented.  相似文献   

4.
A global array of 20 radio observatories was used to measure the three-dimensional position and velocity of the two meteorological balloons that were injected into the equatorial region of the Venus atmosphere by the VEGA spacecraft. Initial analysis of only radial velocities indicates that each balloon was blown westward about 11,500 kilometers (8000 kilometers on the night side) by zonal winds with a mean speed of about 70 meters per second. Excursions of the data from a model of constant zonal velocity are generally less than 3 meters per second; however, a much larger variation is evident near the end of the flight of the second balloon. Consistent systematic trends in the residuals for both balloons indicate the possibility of a solar-fixed atmospheric feature.  相似文献   

5.
The second flight of the International Microgravity Laboratory (IML-2) on Space Shuttle flight STS-65 provided a unique opportunity for the intercomparison of a wide variety of radiation measurement techniques. Although this was not a coordinated or planned campaign, by sheer chance, a number of space radiation experiments from several countries were flown on this mission. There were active radiation measuring instruments from Japan and US, and passive detectors from US, Russia, Japan, and Germany. These detectors were distributed throughout the Space Shuttle volume: payload bay, middeck, flight deck, and Spacelab. STS-65 was launched on July 8, 1994, in a 28.45 degrees x 306 km orbit for a duration of 14 d 17 hr and 55 min. The crew doses varied from 0.935 mGy to 1.235 mGy. A factor of two variation was observed between various passive detectors mounted inside the habitable Shuttle volume. There is reasonable agreement between the galactic cosmic ray dose, dose equivalent and LET spectra measured by the tissue equivalent proportional counter flown in the payload bay with model calculations. There are significant differences in the measurements of LET spectra measured by different groups. The neutron spectrum in the 1-20 MeV region was measured. Using fluence-dose conversion factors, the neutron dose and dose equivalent rates were 11 +/- 2.7 microGy/day and 95 +/- 23.5 microSv/day respectively. The average east-west asymmetry of trapped proton (>3OMeV) and (>60 MeV) dose rate was 3.3 and 1.9 respectively.  相似文献   

6.
用黑腹果蝇检查T7A—S1火箭飞行因素的遗传效应。通过两次飞行实验观察,发现亲代雌蝇在飞行后(主要是第4—6天)所产的卵中,无X染色体卵百分率增高而双X染色体卵百分率未见变化。其性质并非个别雌蝇产生了较多的无X染色体卵,而是产生无X染色体卵的雌蝇个数增多。第二次飞行实验结果也呈现,亲代雌蝇在飞行后第4—6天所产的子1代中,三龄幼虫成神经细胞染色体桥频率增高。上述实验结果表明,火箭飞行因素对雌果蝇生殖细胞遗传物质有轻微影响。   相似文献   

7.
8.
An experiment involving active detection of space radiation was carried out in the Space Research Institute (SRI) of Bulgarian Academy of Sciences, in preparation of the flight of the second Bulgarian cosmonaut. The radiations that would be encountered on the flight were modelled including solar and galactic cosmic rays and the particle radiation in the Earth's radiation belts. The dose rate was calculated for these different radiations behind the shielding of the space station. The variations in dose rates over the period of the flight were calculated and compared with measurements made during the orbit of the Mir Space Station. The calculated and measured dose rates agreed within 15-35%.  相似文献   

9.
The Ballooncraft Support Systems were developed by NASA Wallops Flight Facility for use on ULDB class balloon missions. The support systems have now flown two missions supporting the Cosmic Rays Energetics and Mass (CREAM) experiment. The first, CREAM I, flown in December 2004, was for a record breaking 41 days, 21 h, and the second flight flown in December 2005, was for 28 days, 9 h. These support systems provide CREAM with power, telecommunications, command, and data handling including flight computers, mechanical structures, thermal management, and attitude control to help ensure a successful scientific mission. This paper addresses the performance and success of these support systems over the two missions.  相似文献   

10.
A balloon-borne winching system providing an improved in-situ observational method for stratospheric photochemistry research was first reported to COSPAR two years ago. Sice that time a second flight has been successfully conducted in which a more complex detection package (98 kg) was twice lowered from a float altitude of 39 km for a distance of 8 km, and each time reeled back up to the winch. Controlled velocities of 4 to 7 meters/sec were implemented for both scans, and the package was brought to a brief stop during the first to evaluate the dynamic effects. Instrumentation aboard both the winch and the detection package again did not identify any threatening dynamic perturbations during any phase of the flight, thus indicating that long extension reeling in the stratosphere can now be conducted on an operational basis. The remaining minor problem areas in the payload are summarized, as are some directions planned for future utilization.  相似文献   

11.
The influence of space flight factors on viability and mutability of plants.   总被引:11,自引:0,他引:11  
The experiments with air-dried Crepis capillaris seeds aboard the Soyuz 16 spaceship and the orbital stations Salyut 5, 6, 7 have revealed an increase in the frequency of aberrant cells in seedlings grown from flight-exposed seeds during the flight (experiment) and after the flight on Earth (flight control) as compared to the ground-based control. The increase in seedlings grown during the flight is more significant than in the flight control. During the flight Arabidopsis thaliana developed from cotyledons to the flowering stage. Analysis of seeds setting on these plants after the flight has shown a reduction in the fertility of these plants and an increase in the frequency of recessive mutants ("Light block-1"). An increased frequency of mutants was also retained in the progeny of plants which had passed through a complete cycle of development during the flight ("Fiton-3"). Suppression of embryo viability was observed in all experiments and expressed itself in reduced germinating ability of seeds from the exposed plants and in the early death of seedlings. Damages resulting from chromosome aberrations are eliminated in the first postflight generation and damages resulting from gene mutations and micro-aberrations are preserved for a longer time.  相似文献   

12.
The Shuttle Multispectral Infrared Radiometer (SMIRR) is a spectroradiometer covering the region from 0.5 to 2.5 μm in 10 channels that acquired data from spots 100 m in diameter along the subspacecraft ground track. It was flown aboard the second flight of the space shuttle Columbia, November 12–14, 1981. Data collected during orbit 16 over southern Egypt show that carbonate rocks, kaolinite, and possibly montmorillonite can be identified by their SMIRR spectral signatures and limited knowledge of the lithologic units present. Detailed analysis of SMIRR data for this area indicates that calcite, kaolinite, and montmorillonite rocks give rise to absorption features that result in characteristic 10 channel spectra.  相似文献   

13.
A dosimetry-radiometry system has been developed at the Space Research Institute of the Bulgarian Academy of Science to measure the fluxes and dose rates on the flight of the second Bulgarian cosmonaut. The dosimetry system is designed for monitoring the different space radiations, such as solar cosmic rays, galactic cosmic rays and trapped particles in the earth radiation belts. The system consists of a battery operated small size detector unit and a "read-write" and telemetry microcomputer unit. The sensitivity of the instrument (3.67 x 10(-8) rad/pulse) permits high resolution measurements of the flux and dose rate along the track of the Mir space station. We report our initial results for the period of the flight between the 7th and 17th June 1988.  相似文献   

14.
Space flight has been shown to affect expression of several cell surface markers. These markers play important roles in regulation of immune responses, including CD4 and CD8. The studies have involved flight of experimental animals and humans followed by analysis of tissue samples (blood in humans, rats and monkeys, spleen, thymus, lymph nodes and bone marrow in rodents). The degree and direction of the changes induced by space flight have been determined by the conditions of the flight. Also, there may be compartmentalization of the response of surface markers to space flight, with differences in the response of cells isolated from blood and local immune tissue. The same type of compartmentalization was also observed with cell adhesion molecules (integrins). In this case, the expression of integrins from lymph node cells differed from that of splenocytes isolated from rats immediately after space flight. Cell culture studies have indicated that there may be an inhibition in conversion of a precursor cell line to cells exhibiting mature macrophage characteristics after space flight, however, these experiments were limited as a result of technical difficulties. In general, it is clear that space flight results in alterations of cell surface markers. The biological significance of these changes remains to be established.  相似文献   

15.
飞行器相对姿态运动的静力学、运动学和动力学方法   总被引:5,自引:1,他引:5  
文章系统地研究了飞行器相对姿态运动描述问题 ,提出了求解相对姿态运动的静力学方法、运动学方法和动力学方法 ,特别是在动力学方法中 ,提出了飞行器相对姿态运动的角加速度合成定理。所得结果可作为飞行器相对姿态运动的分析和数值仿真的理论基础 ,并为今后进一步研究飞行器相对运动制导和控制问题打下基础  相似文献   

16.
Three flights of rocket borne electron accelerators have yielded some results concerning the Beam Plasma Discharge (BPD). The first flight, E||B, from Churchill carrying an accelerator of 2 and 4 keV electrons, produced a spectrum of whistler mode waves which was identical with that produced in a large vacuum chamber, and which we know to be an indicator of BPD. The second, Echo V, launched from Poker Flat, Alaska, carrying an accelerator of 25–35 keV electrons, produced wave emissions at 3–3.5 MHz observed on the ground. Our interpretation is that BPD was not or was weakly produced. In the third flight, NB3-II launched from Churchill with an accelerator of 2, 4 and 8 keV electrons, wave emissions well above the ambient plasma frequency were observed from a separated payload, but very close to the beam, and are interpreted as demonstrating BPD.  相似文献   

17.
Crystallisation of alpha-crustacyanin, the lobster carapace astaxanthin-protein was attempted under microgravity conditions in EURECA satellite using liquid-liquid diffusion with polyethyleneglycol (PEG) as precipitant; in a second reaction chamber phenol and dioxan were used as additives to prevent composite crystal growth. Crystals of alpha-crustacyanin grown under microgravity from PEG were larger than those grown terrestrially in the same apparatus under otherwise identical conditions. On retrieval, the crystals from PEG were shown to be composite and gave a powder diffraction pattern. The second reaction chamber showed leakage on retrieval and had also been subjected to rapid temperature variation during flight. Crystal fragments were nevertheless recovered but showed a powder diffraction pattern. It is concluded, certainly for liquid-liquid diffusion using PEG alone, that, for crustacyanin, although microgravity conditions resulted in an increase in dimensions of crystals, a measurable improvement in molecular ordering was not achieved.  相似文献   

18.
The Advanced Thin Ionization Calorimeter (ATIC) Balloon Experiment had a successful test flight and a science flight in 2000–01 and 2002–03 and an unsuccessful launch in 2005–06 from McMurdo, Antarctica, returning 16 and 19 days of flight data. ATIC is designed to measure the spectra of cosmic rays (protons to iron). The instrument is composed of a Silicon matrix detector followed by a carbon target interleaved with scintillator tracking layers and a segmented BGO calorimeter composed of 320 individual crystals totaling 18 radiation lengths to determine the particle energy. BGO (Bismuth Germanate) is an inorganic scintillation crystal and its light output depends not only on the energy deposited by particles but also on the temperature of the crystal. The temperature of balloon instruments during flight is not constant due to sun angle variations as well as differences in albedo from the ground. The change in output for a given energy deposit in the crystals in response to temperature variations was determined.  相似文献   

19.
针对无人机(UAV)操纵质量高低多依赖专家主观评判、不同飞行动作缺乏针对性评判标准的问题,建立了根据飞行数据客观评价无人机平飞动作质量的模型。首先通过建立平飞判别规则识别无人机飞行数据中的平飞动作数据段,然后根据布林通道理论计算各平飞数据段内多个飞行参数的得分值,最后通过"熵权法"确定各参数的权重,进而得到反映不同无人机操控手平飞动作质量的指标数据。将一次四边平飞训练任务中4组不同无人机操控手操纵和1组无人机自主控制的飞行数据输入该模型,计算结果表明,模型可以较好地识别平飞动作并区分不同操控手平飞动作质量的高低,可以为无人机操控手的训练提供参考。   相似文献   

20.
A new Atmospheric Ionizing Radiation (AIR) model is currently being developed for use in radiation dose evaluation in epidemiological studies targeted to atmospheric flight personnel such as civilian airlines crewmembers. The model will allow computing values for biologically relevant parameters, e.g. dose equivalent and effective dose, for individual flights from 1945. Each flight is described by its actual three dimensional flight profile, i.e. geographic coordinates and altitudes varying with time. Solar modulated primary particles are filtered with a new analytical fully angular dependent geomagnetic cut off rigidity model, as a function of latitude, longitude, arrival direction, altitude and time. The particle transport results have been obtained with a technique based on the three-dimensional Monte Carlo transport code FLUKA, with a special procedure to deal with HZE particles. Particle fluxes are transformed into dose-related quantities and then integrated all along the flight path to obtain the overall flight dose. Preliminary validations of the particle transport technique using data from the AIR Project ER-2 flight campaign of measurements are encouraging. Future efforts will deal with modeling of the effects of the aircraft structure as well as inclusion of solar particle events.  相似文献   

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