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Simulation of culmulated microimpacts of micro debris to solar cells and function degradation

Huang Jiam-Guo,Liu Dan-Qiu,Gao Zhu-Xiu,Li Hong-Wei,Cai Ming-Hui,Han Jian-Wei,

物理学报 , 2012,
Abstract: The cumulated impacts of the space micro debris on the solar cells is experimentally simulated on the plasma dynamic accelerator in CSSAR. For a duration of ten years on the typical sun synchronous orbit, the solar cell functional degradation due to the micro impacts is measured, and the result accords well with the predicted result according to the impacting damage equation.
Origin and Evolution of Life Constraints on the Solar Model  [PDF]
K Michaelian, O Manuel
Journal of Modern Physics (JMP) , 2011, DOI: 10.4236/jmp.2011.226068
Abstract: Life arose as a non-equilibrium thermodynamic process to dissipate the photon potential generated by the hot Sun and cold outer space. Evidence from the geochemical record of the evolutionary history of life on Earth suggests that life originated in a hot aqueous environment dissipating UV light and evolved later to dissipate visible light. This evidence places constraints on models of solar origin and evolution. The standard solar model seems less compatible with the data than does the pulsar centered solar model.
On-Orbit Degradation of Solar Instruments  [PDF]
A. BenMoussa,S. Gissot,U. Schühle,G. Del Zanna,F. Auchère,S. Mekaoui,A. R. Jones,D. Walton,C. J. Eyles,G. Thuillier,D. Seaton,I. E. Dammasch,G. Cessateur,M. Meftah,V. Andretta,D. Berghmans,D. Bewsher,D. Bolsée,L. Bradley,D. S. Brown,P. C. Chamberlin,S. Dewitte,L. V. Didkovsky,M. Dominique,F. G. Eparvier,T. Foujols,D. Gillotay,B. Giordanengo,J. -P. Halain,R. A. Hock,A. Irbah,C. Jeppesen,D. L. Judge,M. Kretzschmar,D. R. McMullin,B. Nicula,W. Schmutz,G. Ucker,S. Wieman,D. Woodraska,T. N. Woods
Physics , 2013, DOI: 10.1007/s11207-013-0290-z
Abstract: We present the lessons learned about the degradation observed in several space solar missions, based on contributions at the Workshop about On-Orbit Degradation of Solar and Space Weather Instruments that took place at the Solar Terrestrial Centre of Excellence (Royal Observatory of Belgium) in Brussels on 3 May 2012. The aim of this workshop was to open discussions related to the degradation observed in Sun-observing instruments exposed to the effects of the space environment. This article summarizes the various lessons learned and offers recommendations to reduce or correct expected degradation with the goal of increasing the useful lifespan of future and ongoing space missions.
Origin of solar magnetism  [PDF]
Arnab Rai Choudhuri
Physics , 2010, DOI: 10.1017/S1743921311014967
Abstract: The most promising model for explaining the origin of solar magnetism is the flux transport dynamo model, in which the toroidal field is produced by differential rotation in the tachocline, the poloidal field is produced by the Babcock--Leighton mechanism at the solar surface and the meridional circulation plays a crucial role. After discussing how this model explains the regular periodic features of the solar cycle, we come to the questions of what causes irregularities of solar cycles and whether we can predict future cycles. Only if the diffusivity within the convection zone is sufficiently high, the polar field at the sunspot minimum is correlated with strength of the next cycle. This is in conformity with the limited available observational data.
The Origin of the Solar System  [PDF]
Michael Perryman
Physics , 2011,
Abstract: This article relates two topics of central importance in modern astronomy - the discovery some fifteen years ago of the first planets around other stars (exoplanets), and the centuries-old problem of understanding the origin of our own solar system, with its planets, planetary satellites, asteroids, and comets. The surprising diversity of exoplanets, of which more than 500 have already been discovered, has required new models to explain their formation and evolution. In turn, these models explain, rather naturally, a number of important features of our own solar system, amongst them the masses and orbits of the terrestrial and gas giant planets, the presence and distribution of asteroids and comets, the origin and impact cratering of the Moon, and the existence of water on Earth.
Effects of the Boron-Doped p+ Emitter on the Efficiency of the n-Type Silicon Solar Cell  [PDF]
Eun-Young Kim,Jeong Kim
Advances in Materials Science and Engineering , 2013, DOI: 10.1155/2013/974507
Abstract: The optimum structure of the p+ emitter for the n-type silicon solar cell was determined with the simulation of the boron doping concentration. The boron concentration ( ) in the p+ emitter was varied in the range of and ?atoms/cm3 while maintaining the base doping concentration at ?atoms/cm3. With the increase of the boron concentration, the open circuit voltage ( ) of the cell increased up to 0.525?V and then was nearly saturated at ?atoms/cm3. On the other hand, the short circuit current density ( ) began to decrease at ?atoms/cm3 due to the increase of the surface recombination loss, and without considering the variation of the contact resistance along the emitter doping level, the maximum efficiency of the cell was obtained at around ?atoms/cm3. While the contact resistance of the electrode decreases with the increase of the doping concentration in the p+ emitter, and with consideration of the variation of the contact resistance, the optimum value of for maximum efficiency shifted to the higher doping level. 1. Introduction Currently, the p-type silicon solar cell comprises a large portion of the industrial solar cells. On the other hand, the n-type silicon solar cell has been known to have many advantages and has subsequently received a great deal of attention and has become one of the main development topics in PV industries. Crystalline silicon solar cell using the n-type wafer showed the highest efficiency record among commercial silicon solar cells [1]. The n-type wafer has a longer diffusion length than the p-type wafer as a result of a higher tolerance to common transition metal impurities [2, 3]. Also, it does not contain any boron-oxide pairs, which are considered as the origin of light-induced degradation (LID) in the p-type Si wafer [4]. Thus, the performance of the n-type silicon solar cell can almost be maintained without degradation during the illumination of light. Furthermore, since the doping profile of boron is more similar to the theoretical model than that of phosphorous, the application of simulation to the real emitter diffusion process is more suitable for the n-type Si wafer. In spite of the definite advantages of n-type silicon, p-type silicon comprises 85% of industrial silicon solar cells. Historically, research and process infrastructure have been mainly developed for p-type silicon solar cells, which are essential to make economical and high-efficient commercial solar cells. In order to realize a p+ emitter on n-type silicon wafer, three kinds of methods are usually applied: (i) boron-diffused emitter, (ii) Al-alloyed
The origin of the solar magnetic cycle  [PDF]
Arnab Rai Choudhuri
Physics , 2011, DOI: 10.1007/s12043-011-0113-4
Abstract: After summarizing the relevant observational data, we discuss how a study of flux tube dynamics in the solar convection zone helps us to understand the formation of sunspots. Then we introduce the flux transport dynamo model and assess its success in modelling both the solar cycle and its departures from strictly periodic behaviour.
Solar wind origin of terrestrial water  [PDF]
Hans Merkl,Markus Fraenz
Physics , 2011,
Abstract: The origin of the Earth water reserves during the evolution of the planet is one of the big miracles in geophysics. Common explanations are storage of water in the Earth mantle at a time when the crust had not yet formed and depositing of water by comets during the time of late heavy bombardement. Both explanations have different problems - especially when comparing with the evolution of Mars and Venus. Here we discuss the possible role of hydrogen collected from the solar wind by the early Earth magnetosphere. While the water production by solar wind capture is very small today it may have been significant during the first billion years after planetary formation because solar wind was much stronger at that time and Earth magnetospheric configuration may have been different. We estimate that the contribution of solar wind hydrogen to the Earth water reserves can be up to 10% when we assume a that the Earth dipole acted as a collector and early solar wind was 1000 times stronger than today. We can not even exclude that solar wind hydrogen was the main contributor to Earth water reserves.
On the origin of solar oscillations  [PDF]
P. L. Goode,L. H. Strous,T. R. Rimmele,R. T. Stebbins
Physics , 1998, DOI: 10.1086/311203
Abstract: We have made high resolution observations of the Sun in which we identify individual sunquakes and see power from these seismic events being pumped into the resonant modes of vibration of the Sun. A typical event lasts about five minutes. We report the physical properties of the events and relate them to theories of the excitation of solar oscillations. We also discuss the local seismic potential of these events.
A Theory of the Origin of the Solar System
Annals of Geophysics , 1969, DOI: 10.4401/ag-5087
Abstract: theory of tlie origin of the solar system is propounded. The approach belongs to the dualistic class of theories but still retains all the essential features of a monistic theory. It emphasizes the need of a foreign body approaching the solar nebula for the occurrence of an instability in the boundary layer of the nebular disc. This foreign body is postulated to be a brother star of the Sun in the sense that both belong to a common central parent body such as any two successive planets belong to the Sun. The analysis gives a law of distance of the planets from tlie Sun. This law is obeyed separately by both the groups of the planets more closely than the existing Titius - Bode's law. The law is also found to be applicable in the various satellite systems.
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