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91.
A new subgroup of3He rich solar flares is found on reanalysing the global data.3He/H ratio as a function of maximum proton flux at an energy of about 10 MeV shows a break-up of the data into two groups.
The first group follows the anticorrelation of3He/H ratio with the proton flux, as expected in the plasma process acceleration models. But the second group has a constant3He/H ratio as a function of maximum proton flux. This is not in conformity with the plasma process models. But this is expected
in models where the nuclear spallation reactions are responsible for the production of3He. It is also found that the same break-up into two distinct groups follows if one plots the location of the flares in the
solar disc. The first group is more or less confined to the west limb of the Sun, whereas the second group is more widely
spread out across the solar disk.
Visiting Professor, Tata Institute of Fundamental Research, Bombay, August–September, 1983. 相似文献
92.
93.
Suresh Chandra 《Pramana》1980,14(1):41-46
The effect of dielectronic recombination as an excitation process in the intensity of solar x-ray lines of calcium ions is
investigated. It is found that x-ray line intensities are enhanced by 15% to 88% with the inclusion of dielectronic recombination
as an excitation mechanism. 相似文献
94.
F. Cavallini G. Ceppatelli A. Righini F. Berrilli B. Caccin S. Cantarano A. Egidi P. Francia E. Pietropaolo 《Il Nuovo Cimento C》1992,15(5):509-518
Summary We describe an optical device consisting of a Universal Birefringent Filter and a Fabry-Perot interferometer used in tandem
to obtain monochromatic images of the Sun in the visible spectrum (between 4200 and 7000 ?). The spectral resolving power
is about 300000 and the wavelength stability might reach 0.02 m? at 5000 ? (≈1.2 m/s) with an integration time of 1 s. The
image is recorded by a CCD camera based on a Thomson THX31159 device with 512×512 square pixels 19 μm in size. A prototype
of this instrument was tested at the G. B. Donati Solar Tower of the Arcetri Astrophysical Observatory by obtaining, at fixed
time intervals, several series of full disk monochromatic images of the Sun at different wavelengths inside the Fe I 5905.7
? photospheric line. In this paper we describe the instrument and its characteristics and we give an cccount of the preliminary
results obtained by measuring the global velocity field on the solar photosphere. These results show that the instrument is
well suited for global oscillation measurements.
Paper presented at the V Cosmic Physics National Conference, S. Miniato, November 27–30, 1990. 相似文献
95.
Shiyong Liu Xiangbo Zeng Wenbo Peng Haibo Xiao Wenjie Yao Xiaobing Xie Chao Wang Zhanguo Wang 《Journal of Non》2011,357(1):121-125
We develop a double-layer p-type hydrogenated nanocrystalline silicon (p-nc-Si:H) structure consisting of a low hydrogen diluted i/p buffer layer and a high hydrogen diluted p-layer to improve the hydrogenated amorphous silicon (a-Si:H) n-i-p solar cells. The electrical, optical and structural properties of p-nc-Si:H films with different hydrogen dilution ratio (RH) are investigated. High conductivity, low activation energy and wide band gap are achieved for the thin films. Raman spectroscopy and high-resolution transmission electron microscopy (HRTEM) analyses indicate that the thin films contain nanocrystallites with grain size around 3-5 nm embedded in the amorphous silicon matrix. By inserting a p-nc-Si:H buffer layer at the i/p interface, the overall performance of the solar cell is improved significantly compared to the bufferless cell. The improvement is correlated with the reduction of the density of defect states at the i/p interface. 相似文献
96.
The emission spectra of the A2П-X2Σ+ (red) system of 12C14N have been reinvestigated in the 3500-22 000 cm−1 region at high resolution using a Fourier transform spectrometer. In total, spectra of 63 bands involving vibrational levels up to v′ = 22 of the A2П state and v″ = 12 of the X2Σ+ ground state have been measured and rotationally analyzed providing an improved set of spectroscopic constants. The present measurements of the Δv = −2 sequence bands of 12C14N and those of 13C14N from Ram et al. (2010) [36] allow for a much improved identification of these two isotopologues in the near infrared spectra of carbon stars. 相似文献
97.
Frank Hase Lloyd Wallace Jeremy J. Harrison 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(4):521-528
The ACE-FTS is a space-borne Fourier transform spectrometer onboard SCISAT-1. The satellite was launched in August 2003 and since February 2004 the ACE-FTS has been performing solar occultation measurements in order to infer the chemical composition of the terrestrial atmosphere. The individual spectra recorded at the highest limb tangent altitudes (above 160 km) are by definition “high sun” spectra and contain no atmospheric contribution. In this work, an empirical solar spectrum covering the 700 to 4430 cm−1 spectral range has been constructed from an average of 224,782 individual ACE-FTS solar spectra. Line assignments have been made for about 12,000 lines. The spectrum and two line lists are provided in the supplemental material attached to this work. Due to the excellent noise level achieved in the ACE-FTS solar atlas presented here, numerous weak absorption features are assigned which were not detectable in the ATMOS solar observations. 相似文献
98.
K. Chance R.L. Kurucz 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(9):1289-1295
We have developed an improved solar reference spectrum for use in the analysis of atmospheric spectra from vacuum wavelengths of 200.07 through 1000.99 nm. The spectrum is developed by combining high spectral resolution ground-based and balloon-based solar measurements with lower spectral resolution but higher accuracy irradiance information. The new reference spectrum replaces our previous reference spectrum, and its derivatives, for use in a number of physical applications for analysis of atmospheric spectra, including: wavelength calibration; determination of instrument transfer (slit) functions; Ring effect (Raman scattering) correction; and correction for spectral undersampling of atmospheric spectra, particularly those that are dilute in absorbers. The applicability includes measurements from the GOME, SCIAMACHY, OMI, and OMPS satellite instruments as well as aircraft-, balloon-, and ground-based measurements. 相似文献
99.
We propose a novel system of a nano-waveguide that can be used to generate the continuous optical spectrum, i.e. white light. A system consists of two micro-ring resonators and a nano-ring resonator that can be integrated into a single system. The large bandwidth signal is generated using a soliton pulse propagating within a Kerr-type nonlinear medium, whereas the continuous bandwidth or wavelength of light signal can be performed. Results obtained have shown the potential of using such a system for white light source generation and amplification, which is discussed. The amplified pulse can be stored within a nano-waveguide, which is allowed to form the continuous spectrum after amplification. Alternatively, the low-level solar radiation can be amplified, and the bandwidth signals can also be enlarged. 相似文献
100.
Yeon Hwa Jo 《Applied Surface Science》2010,256(22):6819-6823
This work reports unexpected crystallization and segregation behavior of CuIn0.7Ga0.3Se2 (CIGS) thin films deposited on flexible Cu foils by pulsed laser deposition. A composite-type microstructure containing nanometer-scaled CIGS crystallites embedded in amorphous Cu-rich matrix is observed even at the high temperature of 500 °C. The findings are attributed to very fast condensation of the ablated species and random nucleation induced from the amorphous matrix. Cu-rich particulates tend to precipitate on the film surface, and their average size, shape, number density and composition exhibit a strong dependence on the substrate temperature up to 500 °C. The similar crystallization properties of the films on Cu foils and glass substrates are noticeable to the use of Cu foils for flexible solar cells. 相似文献