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1.
Summary Data from four neutron monitors, Climax (1953–1976), Deep River (1964–1977), Mt. Norikura (1957–1983) and Tokyo (1970–1983)
are analysed. Power spectra reveal peaks at frequency 1c/16 months for all the stations. Harmonic analysis for the 16-month
period is performed after eliminating the long-term solar-cycle variation. There is general agreement in the phases of the
mean vectors for various neutron monitors. The amplitude averaged over all the four stations is 0.41±0.01, while it is higher
for the two stations having lower cut-off rigidity as compared to that of the other two. The vectors are seen to become more
consistent in phase for periods of minimum solar activity than those for maximum-activity period. The summation dials reveal
abrupt changes in the directions of the 16-month wave vector corresponding to the reversal of polarity of the solar magnetic
field. Comparison of the 16-month wave of sunspot activity with that of cosmic-ray intensity, however, does not show any significant
correlation.
Riassunto Si analizzano dati da quattro monitor di neutroni, Climax (1953–1976), Deep River (1964–1977), Mt. Norikura (1957–1983) e Tokyo (1970–1983). Gli spettri di frequenza rivelano picchi alla frequenza di 1 ciclo ogni 16 mesi per tutte le stazioni. Si effettua un'analisi armonica per un periodo di 16 mesi dopo aver eliminato la variazione del ciclo solare a lungo termine. Esiste un accordo generale riguardo alle fasi dei vettori medi per vari monitor di neutroni. L'ampiezza media rispetto a tutte e quattro le stazioni è di 0.41±0.01, mentre risulta superiore per le due stazioni che presentano una rigidità di taglio inferiore alle altre due. Si osserva una crescente coerenza di fase dei vettori in periodi di attività solare minima, rispetto a quella in periodi di attività massima. I grafici della somma rivelano cambiamenti repentini nelle direzioni del vettore d'onda di 16 mesi, corrispondenti all'inversione di polarità del campo magnetico del Sole. Il confronto di un'onda di 16 mesi dell'attività delle macchie solari con quella dell'intensità dei raggi cosmici, tuttavia, non mostra nessuna correlazione significativa.相似文献
2.
N. A. Van Bui I. M. Martin A. Turtelli Yu. I. Stozhkov V. V. Sibikin M. I. Fradkin A. Svirzhevskaya 《Il Nuovo Cimento C》1989,12(6):811-818
Summary To investigate the variation of the cosmic-ray intensity in the Earth atmosphere, stratospheric balloon soundings are performed
weekly at Campinas (Brazil). During the flight of May 20th, 1988 short-period variations were detected. Through Fourier analysis
it was identified a period of ∼2.5 min, with a confidence level of 99.6% between 23 g/cm2 and 173 g/cm2. Apparently these oscillations are not correlated either with the earth magnetic field or solar activity, suggesting their
atmospheric origin, nevertheless it is difficult to explain the production mechanisms of these disturbances.
Riassunto Per studiare le variazioni dell'intensità dei raggi cosmici nell'atmosfera terrestre sono messi in funzione palloni sonda stratosferici settimanalmente a Campinas (Brasile). Durante il volo del 20 Maggio 1988 sono state registrate variazioni a breve periodo. Mediante l'analisi di Fourier è stato identificato un periodo di ≈2.5 min con un livello di confidenza di 99.6% tra 23 g/cm2 e 173 g/cm2. Apparentemente queste oscillazioni non sono correlate né con il campo magnetico terrestre né con l'attività solare, il che suggerisce la loro origine atmosferica, nonostante sia difficile spiegare i meccanismi di produzione di queste perturbazioni.
Резюме для исследования изменения интенсивности комсических лучей в земной атмосфере еженелельно запускайтся стратосферные шарызонды в лаборатории Кампинас (Бразилия). Во время подыта 20 мая 1988 года, были зарегистрированы изменения с коротким периодом. С помощью фурье-анализа определен период 2.5 минуты, с уровнем достоверности 99.6%, в области между 23 г/см2 и 173 г/см2. По-видимому, эти осцилляции не связаны ни с магнитным полем Земли, ни с солнечной активностью. Предполагается их атмосферное происхождение, тем не менее трудно обБяснить механизм образования этих возмущений.相似文献
3.
N. A. Van Bui C. A. Vieira L. P. Borovkov V. A. Zhavkov V. A. Tumanov 《Il Nuovo Cimento C》1993,16(1):9-15
Summary The energy deposition by slowing-down of energetic ionizing particles in the atmosphere enhances the production of constituent
concentration which perturbs and eventually destroys the ozone (OZ) layer. Near the Brazilian anomaly region the cosmic-ray
(CR) intensity varies greatly due to the magnetic activity in that region. In order to study these variations, stratospheric
balloons were launched to measure, simultaneously, the CR and OZ fluxes in the atmosphere. The Fourier-analysed data collected
during the flight on April 22, 1989 show evidences of a short-period variation for both fluxes measured. Attempts to verify
the physical mechanisms which associate the CR change with the OZ one are not conclusive due to limited data observed on that
event. 相似文献
4.
We apply a recently developed wavelet based approach to characterize the correlation and scaling properties of non-stationary financial time series. This approach is local in nature and it makes use of wavelets from the Daubechies family for detrending purpose. The built-in variable windows in wavelet transform makes this procedure well suited for the non-stationary data. We analyze daily price of NASDAQ composite index for a period of 20 years, and BSE sensex index, over a period of 15 years. It is found that the long-range correlation, as well as fractal behavior for both the stock index values differ from each other significantly. Strong non-statistical long-range correlation is observed in BSE index, whose removal revealed a Gaussian random noise character for the corresponding fluctuation. The NASDAQ index, on the other hand, showed a multifractal behavior with long-range statistical correlation. 相似文献
5.
B. Baschiera G. Basini H. Bilokon B. D'Ettorre Piazzoli G. Mannocchi C. Castagnoli P. Picchi 《Il Nuovo Cimento C》1979,2(4):473-487
Summary Absolute differential and integral muon intensities below 1 Ge V/c have been measured with a flash-tube range spectrograph
in which stopping muons are identified by the decay sequence. The differential intensities at 0.314 GeV/c and 0.805 GeV/c
are (3.25±0.17)·10−3 cm−2 sr−1·s−1 (GeV/c)−1 and (3.60±0.18)·10−3 cm−2 sr−1 s−1 (GeV/c)−1, respectively,i.e. 16% and 33% higher than that of Rossi. These measurements confirm the rencent results of other authors according to which
the Rossi reference point at 1 GeV/c is too low of about 25%. Our integral measurements at 0.457 GeV/c and 0.918 GeV/c support
this evidence.
Резюме Измерены абсолютные дифферецниальные и интегральные интенсивности мюонов ниже 1 ГэB/c, используя спектрограф, в котором остановившиеся
мюоны идентифицируются по цепочке распадов. Диффенциальные интенсивностн при 0.314 ГэB/c и 0.805 ГэB/c соответственно составляют
(3.25±0.17)·10−3 см−2 ср−1 с−1 (ГэВ/с)−1 и (3.60±0.18)·10−3 см−2 ср−1 с−1 (ГэВ/с)−1, т.е. нв 16% и 33% выше результатов Росси. Проведенные измерения подтвершдают недавние результаты других авторов, согласно
которым точка отсчета Росси при 1 ГэВ/с расподожена ниже на 25%. Наши интегральные измерения при 0.457 ГэВ/с и 0.918 ГэВ/с
подтверждают этот результат.
Riassunto Con uno spettrografo a range di tubi a flash sono state misurate le intensità differenziali e integrali sotto 1 GeV/c rivelando la catena del decadimento del muone. Le intensità differenziali a 0.314 GeV/c e 0.805 GeV/c sono rispettivamente (3.25±0.17)·10−3 cm2 sr−1 s−1 (GeV/c)−1 e (3.60±0.18)·10−3 cm−2 sr−1 s−1 (GeV/c)−1, cioè 16% e 33% più alte di quella di Rossi. Queste misure confermano i recenti risultati di altri autori secondo i quali il punto di riferimento di Rossi a 1 GeV/c è più basso di∼25%. Le nostre misure d'intensità integrale a 0.457 GeV/c e 0.918 GeV/c sostengono queste evidenze.相似文献
6.
《Waves in Random and Complex Media》2013,23(3):S57-S64
Abstract The influence of internal surface reflectivity is incorporated into a heuristic model of long-range intensity correlation. This allows us to identify the spatial intensity correlation function in a sample of randomly positioned polystyrene spheres as the sum of a first-order term in the correlation parameter κ, which falls linearly with detector separation, and a constant term, which is of order κ2. κ is a measure of the proximity to the localization threshold. In a sample which is a mixture of metallic and dielectric spheres and in which κ becomes large, the probability of large intensity fluctuations increases. The distribution of intensities is then found to be stretched exponential even for sample lengths which are comparable to the wavelength of the radiation. 相似文献
7.
The influence of internal surface reflectivity is incorporated into a heuristic model of long-range intensity correlation. This allows us to identify the spatial intensity correlation function in a sample of randomly positioned polystyrene spheres as the sum of a first-order term in the correlation parameter κ, which falls linearly with detector separation, and a constant term, which is of order κ2. κ is a measure of the proximity to the localization threshold. In a sample which is a mixture of metallic and dielectric spheres and in which κ becomes large, the probability of large intensity fluctuations increases. The distribution of intensities is then found to be stretched exponential even for sample lengths which are comparable to the wavelength of the radiation. 相似文献
8.
Arthur Jabs 《Zeitschrift für Physik A Hadrons and Nuclei》1968,212(3):222-234
The flux of nucleons, pions, and muons in the energy range 1–1000 GeV and in atmospheric altitudes of 0–48 km has been calculated to a high degree of accuracy and without gross simplifications. Thus a discrepancy indicated already in 1964 byBrooke, Hayman, Kamiya andWolfendale has been firmly established. The discrepancy means, that it has proved impossible to derive the measured nucleon and muon spectra near sea-level from the measured primary nucleon spectrum unless the primary spectrum is reduced by a factor of about 2.5 or the high-energy collision models commonly used are changed. The latter would mean that the fraction of energy lost by the nucleon in a collision is passed over to the muon component to a minor extent than so far accepted, and this may be achieved in two ways: either the ratio of collision energy passed on to the electron-photon component to the energy passed on to the pion-muon component is increased in favour of the former, or about 10–20% of the collision energy are passed on to unspecified particles which do not contribute appreciably to the hard and weak components of cosmic rays. — The possibility is discussed that the missing fraction of 10–20% is spent in production of baryonantibaryon pairs. 相似文献
9.
Sandro Faetti Crescenzo Festa Leone Fronzoni Paolo Grigolini Fabio Marchesoni Vincenzo Palleschi 《Physics letters. A》1983,99(1):25-28
The effect of increasing the intensity of multiplicative noise is studied from both theoretical and experimental point of view. The experiment, based on analog devices, is shown to lead to a qualitative agreement with the results of a continued-fraction calculation. The reasons for the discrepancy with a “numerical experiment” recently made by other authors are discussed. 相似文献
10.
Christopher D. Carone Ari Cukierman Reinard Primulando 《Physics letters. [Part B]》2011,704(5):541-546
We consider possible leptonic three-body decays of spin-1/2, charge-asymmetric dark matter. Assuming a general Dirac structure for the four-fermion contact interactions of interest, we study the cosmic-ray electron and positron spectra and show that good fits to the current data can be obtained for both charged-lepton-flavor-conserving and flavor-violating decay channels. We find that different choices for the Dirac structure of the underlying decay operator can be significantly compensated by different choices for the dark matter mass and lifetime. The decay modes we consider provide differing predictions for the cosmic-ray positron fraction at energies higher than those currently probed at the PAMELA experiment; these predictions might be tested at cosmic-ray detectors like AMS-02. 相似文献
11.
N. I. Furashov V. Y. Katkov A. M. Osharin B. A. Sverdlov 《Radiophysics and Quantum Electronics》1999,42(12):1007-1013
We measure the dependence of radio wave attenuation at 138, 247, and 340 GHz over a near-ground radio path of length 1025
m on the snowfall intensity R. We find that the relationship between the attenuation coefficient Γ at the frequency ν and
the intensity R at distinct stages of a snowfall event is close to functional and is mainly nonlinear. This relationship can
be fitted well by the function Γ(ν)=γ(ν)Rm(ν) in the observed range of snowfall intensities (R is not greater than 3 mm/h in terms of the water equivalent). The dependence
of Γ on R at different frequencies may change drastically as the snowfall evolves from one stage to another. The data obtained
at the mentioned frequencies during the entire observation time reveal that the statistical dependence of Γ on R is close
to linear. The mean specific attenuation coefficients determined using this data set turned out to be equal to 0.82, 3.3,
and 5.6 dB·km−1/(mm·h−1) at ν equal to 138, 247, and 340 GHz, respectively. The correlation coefficients turned out to be 0.89, 0.94, and 0.98, respectively.
The obtained results are compared to the data obtained in other measurements, as well as to the theoretical calculations of
the attenuation based on the coupled-dipole method.
Radiophysical Research Institute, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika,
Vol. 42, No. 12, pp. 1145–1152, December 1999. 相似文献
12.
V. Yu. Katkov B. A. Sverdlov N. I. Furashov 《Radiophysics and Quantum Electronics》1997,40(5):414-418
We present experimental data indicating a strong time variation and various manifestations of the relation between attenuation
of short millimeter radio waves and rain intensity, which are due to the dynamics and diversity of precipitation microstructure.
Radiophysical Research Institute, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika,
Vol. 40, No. 5, pp. 626–632, May, 1997. 相似文献
13.
For pure type-II superconductors with κ slightly above 1/√2 it is shown that the preferential orientations of the flux-line lattice relative to the crystal lattice are related to the anisotropy of the coherence length. 相似文献
14.
S. Bhattacharyya 《Il Nuovo Cimento C》1987,10(6):669-676
Summary The rising ratio of cosmic-ray positrons at ultra-high energies of interactions seems to have puzzled the theorists to a great
extent. We have made here a somewhat successful attempt to interpret the behaviour of this ratio,R=e+/(e++e−), by putting into use the main physical ideas from our two previous works. The importance and the implications of this observation
have also been highlighted and emphasized in the proper background.
Riassunto Il crescente rapporto dei positroni dei raggi cosmici ad energie ultra-alte di interazioni sembra aver non poco confuso i teorici. Qui si tenta con un certo successo di interpretare il comportamento di questo rapportoR=e+/(e++e−) usando i principali concetti fisici dei nostri due precedenti lavori. L'importanza e le implicazioni di questa osservazione sono state sottolineate ed enfatizzate nell'appropriato contesto.
Резюме Увеличивающиеся отношение позитронов космических лучей при ультравыс оких энергиях, по-видимому, представляет загадку для теоретиков. В этой статье мы предпринимает отчасти успешную попытку интерпретировать поведение этого отношенияR=e+/(e++e−), используя основные физические идеи из наших двух предыдущих публикаций. Отмчаются важностя и приложения полученных результатов.相似文献
15.
16.
Starting from a nonorthogonal basis set a model Hamiltonian for the chemisorption of two adsorbates is derived. The nonorthogonality is converted into a renormalization of the matrix elements. A solution is presented which becomes exact in two limiting cases. The indirect interaction energy of two hydrogen atoms is calculated for adsorption on a semi infinite simple cubic solid described by ans-band. For the band nearly filled (parameters of Ni) a 2 × 2 structure seems to be energetically favourable. 相似文献
17.
The magnetic properties of electrical steel such as magnetization curves, magnetization behavior and specific magnetic losses are related to the microstructure and the texture of the steel. A quantitative model, which describes the effect of microstructure and texture and their interplay on the magnetic losses P, is still missing. Based on experimental data for nonoriented electrical steels and FeSi-samples with high (Si, Al)-content, a more general formula is proposed for the dependence of P, at a given value of magnetic induction B, as a function of the mean value of the grain size d of the material and of the intensities of the relevant magnetic texture components. 相似文献
18.
On the nature of turbulence 总被引:10,自引:0,他引:10
A mechanism for the generation of turbulence and related phenomena in dissipative systems is proposed.The research was supported by the Netherlands Organisation for the Advancement of Pure Research (Z.W.O.). 相似文献
19.
CJ Isham 《Contemporary Physics》2013,54(3):207-219
The paper contains a relatively non-technical summary of some recent work by the author and Jeremy Butterfield. The goal is to find a way of assigning meaningful truth values to propositions in quantum theory: something that is not possible in the normal, instrumentalist interpretation. The key mathematical tool is presheaf theory where multi-valued, contextual truth values arise naturally. We show how this can be applied to quantum theory, with the ‘contexts’ chosen to be Boolean subalgebras of the set of all projection operators. 相似文献
20.
L. N. Pyatnitskii 《Journal of Experimental and Theoretical Physics》1998,86(1):107-114
A concept of turbulence is presented that is based on the results of an investigation of the structure of a gas flow in a
tube with a square cross section in front of a nonsteady-state moving flame front. It is shown that a region of elevated pressure,
consisting of alternating condensations, is formed in the gas flow near the tube walls. These condensations are the sources
of waves which form a distribution of velocity fluctuations in the gas flow over a wide range of amplitudes, frequencies and
directions. The dynamics of the perturbations at the walls and the configuration of the wave in the gap make it possible to
consider the fluctuations in the flow as pseudochaotic and to use statistical methods to describe them.
Zh. éksp. Teor. Fiz. 113, 191–203 (January 1998) 相似文献