scholarly journals 160 m Pulsations in the Magnetosphere of the Earth Possibly Caused by Oscillations of the Sun

1983 ◽  
Vol 66 ◽  
pp. 451-455
Author(s):  
B.M. Vladimirsky ◽  
V.P. Bobova ◽  
N.M. Bondarenko ◽  
V.K. Veretennikova

AbstractThe measurements of the amplitudes envelope of Pc 3–4 geomagnetic micropulsations obtained at the Borok Geophysical Observatory were analysed by the cosinor method to search for magnetospheric pulsations with a period of about 160 m. 216 days of observations in 1974–1978 were used. It was found that Pc3–4 amplitudes are modulated by the period 160.010 m with a stable phase. The maximum of the Pc3–4 amplitudes follows approximately 20 m after the maximum of the solar expansion velocity (for the center of the disk) in the optical observations of Severny et al. This modulation of the Pc3–4 amplitudes could be caused by the presence of an oscillating component in solar UV radiation over the wavelength range 100-900 Å. The amplitude of the UV flux variation may be as large as 2–4%.

Author(s):  
Renata Chadyšienė ◽  
Aloyzas Girgždys

The paper presents the assessment of ultraviolet radiation from technical sources. It has been determined that the intensity of UVA radiation is about 10 times higher than the intensity of radiation of UVB. It has been investigated that the intensity of UV radiation during the welding process nonlinearly depends on the strength of the current, namely, if the strength of the current is reduced by 60%, the intensity of UV radiation is reduced by 20%, it also depends on the distance from the source, namely, if the distance is increased 10 times, the intensity of UV radiation is reduced about 25 times. The dose of UVA and UVB radiation from various resources is calculated. Comparison with the minimum erythema dose is submitted. It has been obtained that when the strength of the current is 315 A, the UV radiation dose exceeds 1 MED, namely, UVA ∼ 3000, UVB ∼300 times. After having carried out the experiment it has been found that the UV radiation emitted from a welder comprises about 80% of UVA, and about 20% of UVB. The results of investigation made in a solarium show that UV radiation from lamps comprises 98% of UVA radiation and 2% – of UVB radiation, while in the Sun rays reaching the Earth UV radiation comprises 96% of UVA and 4% of UVB. Santrauka Darbe radiometriniais metodais nustatyti ir įvertinti dirbtinių šaltinių skleidžiamos ultravioletinės alfa ir beta spinduliuotės (UVA ir UVB) intensyvumo pokyčiai ir apskaičiuota įvairių šaltinių sukuriama UVA ir UVB spinduliuotės dozė. Nustatyta, kad suvirinimo proceso metu skleidžiamos UV spinduliuotės intensyvumas priklauso nuo šaltinio intensyvumo (sumažinus šaltinio intensyvumą apie 60 %, UV spinduliuotės intensyvumas sumažėja apie 20 %) bei nuo atstumo nuo šaltinio (padidinus atstumą 10 kartų UV spinduliuotės intensyvumas sumažėja apie 25 kartus). Įvairių šaltinių sukuriama UVA ir UVB spinduliuotės dozė palyginama su minimalia eritemine doze. Gauta, kad suvirinimo metu, esant 315 A elektros srovės stipriui, UVA spinduliuotės dozė 1 MED viršija apie 3000, UVB ~ 300 kartų. Nustatyta, kad apie 80 % iš suvirinimo aparato skleidžiamos UV spinduliuotės yra UVA, o apie 20 % – UVB. 98 % soliariumo lempų skleidžiamos UV spinduliuotės yra UVA ir 2 % – UVB, gi iš Žemę pasiekiančios Saulės UV spinduliuotės 96 % yra UVA ir 4 % UVB. Резюме Радиометрическими методами определены изменения УФА- и УФБ-излучений некоторых техногенных источников, а также рассчитана доза УФА- и УФБ-излучений этих источников. Установлено, что в среднем интенсивность УФА-излучения в 10 раз сильнее интенсивности УФБ-излучения. Установлено также, что в процессе сварки интенсивность испускаемого УФ-излучения зависит от интенсивности источника: при снижении интенсивности источника на 60% интенсивность УФ-излучения снижается приблизительно на 20%; при увеличении расстояния от места сварки в 10 раз интенсивность УФ-излучения снижается приблизительно в 25 раз. Рассчитана доза УФАи УФБ-излучений, создаваемая различными техногенными источниками. Представлено ее сравнение с минимальной эритемной дозой. Получено, что во время сварки при силе электрического тока 315 А доза УФА-излучения превышает 1 МЭД в 3000 раз, а УФБ-излучения – в 300 раз. Экспериментальными исследованиями получено, что испускаемое при сварке УФ излучение на 80% состоит из УФА-излучения и на 20% – из УФБ-излучения. В соляриуме, где был проведен эксперимент, УФ-излучение ламп состоит на 98% из УФА лучей и на 2% из УФБ лучей. Для сравнения: околоземное УФ-излучение Солнца в Литве состоит в среднем на 96% из УФА лучей и на 4% из УФБ лучей.


2004 ◽  
Vol 4 (11/12) ◽  
pp. 2543-2552 ◽  
Author(s):  
J. M. Sabburg ◽  
C. N. Long

Abstract. A recent World Meteorological Organisation report discussed the importance of continued study of the effect of clouds on the solar UV radiation reaching the earth's surface. The report mentions that the use of all-sky imagery offers the potential to understand and quantify cloud effects more accurately. There are an increasing number of studies investigating the enhancement of surface solar, UV irradiance, and UV actinic flux, using automated CCD and sky imagers. This paper describes new algorithms applicable to a commercially available all-sky imager (TSI-440), for research investigating cloud enhanced spectral UV irradiance. Specifically, these include three new algorithms relating to cloud amount at different spatial positions from 1) zenith and 2) from the solar position and 3) the visible brightness of clouds surrounding the sun. A possible relationship between UV enhancement and the occurrence of near-sun cloud brightness is reported based on this preliminary data. It is found that a range of wavelength dependent intensities, from 306 to 400 nm, can occur in one day for UV enhancements. Evidence for a possible decreasing variation of intensity with longer wavelengths is also presented.


2010 ◽  
Vol 138 (11-12) ◽  
pp. 752-754
Author(s):  
Milorad Letic

Introduction. Effects of ultraviolet radiation on the skin, the eyes and the immune system are well known. The need for UV radiation protection is popularized by the introduction of UV index. Uneven intensity of UV radiation in different regions in different periods of the year and in different times of the day requires that recommendations for UV radiation protection are given for possible UV index values in those regions. Objective. The aim of the study is to establish a simple and consistent method for the determination of the need for UV radiation protection in Serbia where UV radiation intensity can be approximated as uniform. Methods. Possible values of UV index during the year and the sun elevation during the day in periods throughout the year were used for the determination of maximal possible UV index values. These values were compared to UV index forecasts regarding UV radiation protection. Results. Maximal possible values for UV index were used for producing the colour graph. Colours on the graph indicate the need for UV radiation protection. Green - protection is not needed, yellow - protection is needed, red - protection is obligatory. Comparisons with the need for protection based on forecasts showed congruence in 97% of cases. Conclusion. The use of the graph for the determination of the need for UV radiation protection gives nearly the same results as recommendations based on UV index forecasts. The advantages of the graph are that it gives recommendations for the whole year, for the time intervals during the day in every period of the year and for the whole territory of Serbia.


2004 ◽  
Vol 4 (5) ◽  
pp. 6213-6238 ◽  
Author(s):  
J. M. Sabburg ◽  
C. N. Long

Abstract. A recent World Meteorological Organisation report discussed the importance of continued study of the effect of clouds on the solar UV radiation reaching the earth’s surface. The report mentions that the use of all-sky imagery offers the potential to understand and quantify cloud effects more accurately. There are an increasing number of studies investigating the enhancement of surface UV irradiance, and UV actinic flux, using automated CCD and sky imagers. This paper describes new algorithms applicable to a commercially available all-sky imager (TSI-440), for research investigating cloud enhanced spectral UV irradiance. Specifically, these include three new algorithms relating to cloud amount at different spatial positions and the visible brightness of clouds surrounding the sun. A possible relationship between UV enhancement and the occurrence of near-sun cloud brightness is reported. It is found that a range of wavelength dependent intensities, from 306 to 400 nm, can occur in one day for UV enhancements. Evidence of a decreasing variation of intensity with longer wavelengths is also presented.


2021 ◽  
Vol 3 ◽  
pp. 111-116
Author(s):  
S. N. Shapovalov ◽  

The study presents the results of the correlation analysis for the average seasonal values of intensity of solar UV radiation (297–330 nm), as well as for the energy of the lines of solar spectral irradiance with total solar irradiance and total magnetic field of the Sun for the period of 2008–2018 (the 24th cycle of solar activity). The analysis is carried out using the spectral observations of solar UV radiation at Novolazarevskaya station (Antarctica), the SORCE spacecraft and WSO (Wilcox Solar Observatory) data. The dependence of the UVB-UVA radiation of 280–315 nm (UV-B) and 315–400 nm (UV-A) on changes in the total magnetic field of the Sun is revealed.


1993 ◽  
Vol 139 (2) ◽  
pp. 549-554 ◽  
Author(s):  
J. Díaz ◽  
F. Cussó ◽  
F. Jaque ◽  
G. Lifante ◽  
L. F. Da Silva

1997 ◽  
Vol 161 ◽  
pp. 761-776 ◽  
Author(s):  
Claudio Maccone

AbstractSETI from space is currently envisaged in three ways: i) by large space antennas orbiting the Earth that could be used for both VLBI and SETI (VSOP and RadioAstron missions), ii) by a radiotelescope inside the Saha far side Moon crater and an Earth-link antenna on the Mare Smythii near side plain. Such SETIMOON mission would require no astronaut work since a Tether, deployed in Moon orbit until the two antennas landed softly, would also be the cable connecting them. Alternatively, a data relay satellite orbiting the Earth-Moon Lagrangian pointL2would avoid the Earthlink antenna, iii) by a large space antenna put at the foci of the Sun gravitational lens: 1) for electromagnetic waves, the minimal focal distance is 550 Astronomical Units (AU) or 14 times beyond Pluto. One could use the huge radio magnifications of sources aligned to the Sun and spacecraft; 2) for gravitational waves and neutrinos, the focus lies between 22.45 and 29.59 AU (Uranus and Neptune orbits), with a flight time of less than 30 years. Two new space missions, of SETI interest if ET’s use neutrinos for communications, are proposed.


Author(s):  
J. Hanker ◽  
B. Giammara ◽  
G. Strauss

Only a fraction of the UV radiation emitted by the sun reaches the earth; most of the UVB (290-320nm) is eliminated by stratospheric ozone. There is increasing concern, however, that man-made chemicals are damaging this ozone layer. Although the effects of UV on DNA or as a carcinogen are widely known, preleukemia and acute myeloid leukemia (AML) have only rarely been reported in psoriasis patients treated with 8-methoxypsoralen and UV (PUVA). It was therefore of interest to study the effects of UV on the myeloperoxidase (MP) activity of human neutrophils. The peroxidase activity of enriched leukocyte preparations on coverslips was shown cytochemically with a diaminobenzidine medium and cupric nitrate intensification.Control samples (Figs. 1,4,5) of human bloods that were not specifically exposed to UV radiation or light except during routine handling were compared with samples which had been exposed in one of several different ways. One preparation (Fig. 2) was from a psoriasis patient who had received whole-body UVB phototherapy repeatedly.


2019 ◽  
Vol 15 (1) ◽  
pp. 73-77
Author(s):  
Valentina V. Ukraintseva ◽  
Keyword(s):  
The Sun ◽  

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