Solar Radiation at 1200 MC/S., 600 MC/S., and 200 MC/S

1949 ◽  
Vol 2 (1) ◽  
pp. 48 ◽  
Author(s):  
FJ Lehany ◽  
DE Yabsley
Keyword(s):  
Magnetic Field ◽  
Body Temperature ◽  
Solar Radiation ◽  
Thermal Emission ◽  
Black Body ◽  
Sunspot Area ◽  
The Sun ◽  
Long Period ◽  
Period Variations ◽  
The Magnetic Field

Daily observations of solar radiation at frequencies of 1200 Mc/s., 600 Mc/s., and 200 Mc/s. taken between August 18 and November 30, 1947, are described. The characteristics of the radiation at 200 Mc/s. were in general agreement with those observed by earlier workers. At 600 Mc/s. and 1200 Mc/s., the received intensity was normally steady on any one day but underwent long-period variations over a range of about two to one. The radiation received when the sun was almost free of sunspots corresponded to an effective black-body temperature of 0.5 million �K. at 600 Mc/s. and 0.1 million �K. at 1200 Mc/s. As sunspots appeared, the temperature rose and showed marked oar- relation with sunspot area. It is considered that radiation at these frequencies is entirely thermal in origin and that the long-period variations are at least partly due to the influence of the magnetic field of sunspots on the mechanism of thermal emission from a magneto-ionic medium. On a few occasions, isolated disturbances were observed on 600 Mc/s. and 1200 Mc/s. some of which were associated with chromospheric flares and radio fade-outs. The difficulties arising in the calibration of the apparatus and the steps taken to overcome them are discussed in detail.

Solar Radiation at a Wavelength of 3.18 Centimetres

1950 ◽  
Vol 3 (1) ◽  
pp. 60 ◽  
Author(s):  
HC Minnett ◽  
NR Labrum
Keyword(s):  
Body Temperature ◽  
Solar Radiation ◽  
Black Body ◽  
Sunspot Area ◽  
Probable Error ◽  
The Sun ◽  
Solar Origin ◽  
Unit Increase ◽  
Uniform Disk ◽  
Visible Disk

Solar radiation at a wavelength of 3.18 cm. has been measured over a period of three months. The received intensity was found to vary from day to day and the changes are shown to be closely associated with sunspots. The equivalent black-body temperature of the sun over this period, in the absence of sunspots, was 19,300 �K., with a probable error of �7 per cent. The temperature increased by 8 �K. per unit increase of sunspot area (one unit equals 10-5 times the area of the sun's visible disk). This increase is much less than that at longer microwavelengths. Sudden increases of radiation at 3.18 cm., caused by disturbed conditions in the sun, were found to be rare. A number of bursts were observed and a comparison is made with records of longer wave solar radiation and other phenomena of solar origin. Observations were made during the solar eclipse of November 1, 1948 and the results are consistent with either of two simple brightness distributions on the sun's disk. In the first of these, 74 per cent. of the energy is emitted uniformly by the sun's visible disk and the remaining 26 per cent. by a bright ring around the circumference ; in the second, the whole of the radiation comes from a uniform disk of diameter 1.1 times that of the visible sun.

Long-period variations in the magnetic field of small-scale solar structures

2016 ◽  
Vol 56 (8) ◽  
pp. 1052-1059 ◽  
Author(s):  
P. V. Strekalova ◽  
Yu. A. Nagovitsyn ◽  
A. Riehokainen ◽  
V. V. Smirnova
Keyword(s):  
Magnetic Field ◽  
Small Scale ◽  
Long Period ◽  
Period Variations ◽  
The Magnetic Field

scholarly journals ANALISIS INTENSITAS RADIASI MEDAN MAGNET MATAHARI

2021 ◽  
Vol 7 (1) ◽  
pp. 169
Author(s):  
Sudarti Sudarti ◽  
Sherly Nur Laili
Keyword(s):  
Magnetic Field ◽  
Solar Radiation ◽  
Radiation Intensity ◽  
Low Frequency ◽  
Wave Radiation ◽  
The Sun ◽  
Extremely Low Frequency ◽  
Field Radiation ◽  
C 32 ◽  
The Magnetic Field

ABSTRAKMedan magnet ELF (Extremely Low Frequency) merupakan spektrum gelombang elektromagnetik yang frekuensinya 0-300 Hz. Matahari sumber kehidupan yang memancarkan energinya ke bumi dalam bentuk radiasi gelombang elektromagnetik. Penelitian ini bertujuan untuk membandingkan intensitas radiasi medan magnet alamiah matahari didalam ruangan dan diluar ruangan. Jenis penelitian yang digunakan adalah penelitian eksperimen. Pengukuran intensitas radiasi medan magnet oleh matahari menggunakan alat Electromagnetic Field (EMF) Meter dan thermometer. Penelitian dilakukan mulai pukul 06.00 – 15.00 WIB dimana semakin siang temperatur medan magnet dan radiasi matahari semakin meningkat, kemudian suhu dan intensitas menurun seiring dengan terbenamnya matahari. Teknik analisa data yang digunakan menggunakan SPSS dengan metode interpretasi data. Hasil Penelitian menunjukkan data diluar ruangan memiliki hasil lebih tinggi dibandingkan dengan data hasil penelitian di dalam ruangan yakni rerata suhu didalam ruangan 29,5˚C, 31˚C, 32,36˚C,dan 31,7˚C sedangkan diluar ruangan 30,9˚C, 32,9˚C, 33,4˚C, 32˚C. Rerata medan magnet didalam ruangan sebesar 0,044, 0,224, 0,262, dan 0,326, sedangkan diluar ruangan sebesar 0,098, 0,324, 0,418, dan 0,398.  Data penelitian menunjukkan bahwa semakin tinggi intensitas radiasi matahari mengakibatkan temperatur bumi, dan medan magnet semakin tinggi. Kata kunci: intensitas;matahari; medan magnet;radiasi. ABSTRACTElf magnetic field (Extremely Low Frequency) is a spectrum of electromagnetic waves whose frequency is 0-300 Hz. Sun is a source of life that emits its energy to earth in the form of electromagnetic wave radiation. This study aims to compare the radiation intensity of natural magnetic fields by the sun indoors and outdoors. The type of research used is experimental research. Measurement of magnetic field radiation intensity by the sun using EMF Meter and thermometer. The research was conducted from 06.00 – 15.00 WIB where the more daylight the temperature of the magnetic field and solar radiation increases, then the temperature and intensity decreases with the sunset. Data analysis techniques used using SPSS with data interpretation methods. The results showed that outdoor data had higher results compared to the data of indoor research results, namely the average indoor temperature of 29.5°C, 31°C, 32.36°C, and 31.7°C while outdoors 30.9°C, 32.9°C, 33.4°C, 32°C. The average indoor magnetic field is 0.044, 0.224, 0.262, and 0.326, while outdoors is 0.098, 0.324, 0.418, and 0.398.  Research data shows that the higher the intensity of solar radiation results in the Earth's temperature, and the magnetic field gets higher. Keywords: intensity;sun; magnetic field;radiation.

Emergence of Twisted Magnetic Flux Related Sigmoidal Brightening

2000 ◽  
Vol 179 ◽  
pp. 263-264
Author(s):  
K. Sundara Raman ◽  
K. B. Ramesh ◽  
R. Selvendran ◽  
P. S. M. Aleem ◽  
K. M. Hiremath
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Magnetic Flux ◽  
Ultra Violet ◽  
Active Regions ◽  
Morphological Properties ◽  
Energy Storage And Conversion ◽  
The Sun ◽  
X Rays ◽  
The Magnetic Field

Extended AbstractWe have examined the morphological properties of a sigmoid associated with an SXR (soft X-ray) flare. The sigmoid is cospatial with the EUV (extreme ultra violet) images and in the optical part lies along an S-shaped Hαfilament. The photoheliogram shows flux emergence within an existingδtype sunspot which has caused the rotation of the umbrae giving rise to the sigmoidal brightening.It is now widely accepted that flares derive their energy from the magnetic fields of the active regions and coronal levels are considered to be the flare sites. But still a satisfactory understanding of the flare processes has not been achieved because of the difficulties encountered to predict and estimate the probability of flare eruptions. The convection flows and vortices below the photosphere transport and concentrate magnetic field, which subsequently appear as active regions in the photosphere (Rust & Kumar 1994 and the references therein). Successive emergence of magnetic flux, twist the field, creating flare productive magnetic shear and has been studied by many authors (Sundara Ramanet al.1998 and the references therein). Hence, it is considered that the flare is powered by the energy stored in the twisted magnetic flux tubes (Kurokawa 1996 and the references therein). Rust & Kumar (1996) named the S-shaped bright coronal loops that appear in soft X-rays as ‘Sigmoids’ and concluded that this S-shaped distortion is due to the twist developed in the magnetic field lines. These transient sigmoidal features tell a great deal about unstable coronal magnetic fields, as these regions are more likely to be eruptive (Canfieldet al.1999). As the magnetic fields of the active regions are deep rooted in the Sun, the twist developed in the subphotospheric flux tube penetrates the photosphere and extends in to the corona. Thus, it is essentially favourable for the subphotospheric twist to unwind the twist and transmit it through the photosphere to the corona. Therefore, it becomes essential to make complete observational descriptions of a flare from the magnetic field changes that are taking place in different atmospheric levels of the Sun, to pin down the energy storage and conversion process that trigger the flare phenomena.

Detection of a change in the North-South ratio of count rates of particles of high-energy cosmic rays during a change in the polarity of the magnetic field of the Sun

JETP Letters ◽  
2015 ◽  
Vol 101 (4) ◽  
pp. 228-231
Author(s):  
A. V. Karelin ◽  
O. Adriani ◽  
G. C. Barbarino ◽  
G. A. Bazilevskaya ◽  
R. Bellotti ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Cosmic Rays ◽  
High Energy ◽  
The Sun ◽  
High Energy Cosmic Rays ◽  
The North ◽  
The Magnetic Field

scholarly journals Solar Spike Suggests a More Active Sun

Eos ◽  
2019 ◽  
Vol 100 ◽  
Author(s):  
Nola Redd
Keyword(s):  
Magnetic Field ◽  
The Sun ◽  
Radio Waves ◽  
The Magnetic Field

Radio waves are providing a new way to probe the Sun and suggest that the magnetic field of its corona may be stronger than long thought.

The Sun

2015 ◽  
Author(s):  
Joanna D. Haigh ◽  
Peter Cargill
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Solar Atmosphere ◽  
Space Weather ◽  
Extreme Ultraviolet ◽  
The Sun ◽  
Base Level ◽  
Earth’S Climate ◽  
The Magnetic Field ◽  
Terrestrial Magnetic Field

This chapter discusses how there are four general factors that contribute to the Sun's potential role in variations in the Earth's climate. First, the fusion processes in the solar core determine the solar luminosity and hence the base level of radiation impinging on the Earth. Second, the presence of the solar magnetic field leads to radiation at ultraviolet (UV), extreme ultraviolet (EUV), and X-ray wavelengths which can affect certain layers of the atmosphere. Third, the variability of the magnetic field over a 22-year cycle leads to significant changes in the radiative output at some wavelengths. Finally, the interplanetary manifestation of the outer solar atmosphere (the solar wind) interacts with the terrestrial magnetic field, leading to effects commonly called space weather.

scholarly journals Millimeter and Microwave Activity of the Sun

1990 ◽  
Vol 142 ◽  
pp. 457-465 ◽  
Author(s):  
M. R. Kundu ◽  
S. M. White
Keyword(s):  
Magnetic Field ◽  
Gamma Rays ◽  
Solar Flares ◽  
Gamma Ray ◽  
High Spatial Resolution ◽  
High Resolution Imaging ◽  
The Sun ◽  
Millimeter Wavelengths ◽  
Resolution Imaging ◽  
The Magnetic Field

The emission of solar flares at millimeter wavelengths is of great interest both in its own right and because it is generated by the energetic electrons which also emit gamma rays. Since high-resolution imaging at gamma-ray energies is not presently possible, millimeter observations can act as a substitute. Except for that class of flares known as gamma-ray flares the millimetric emission is optically thin. It can be used as a powerful diagnostic of the energy distribution of electrons in solar flares and its evolution, and of the magnetic field. We have carried out high-spatial-resolution millimeter observations of solar flares this year using the Berkeley-Illinois-Maryland Array (BIMA), and report on the preliminary results in this paper (Kundu et al 1990; White et al 1990). We also report some recent results obtained from multifrequency observations using the VLA (White et al 1990).

scholarly journals 42. Solar cosmic radiation and the interstellar magnetic field

1958 ◽  
Vol 6 ◽  
pp. 404-419 ◽  
Author(s):  
A. Ehmert
Keyword(s):  
Magnetic Field ◽  
Solar Radiation ◽  
Cosmic Radiation ◽  
The Sun ◽  
High Latitudes ◽  
Narrow Angle ◽  
The Earth ◽  
Order Of Magnitude ◽  
The Impact ◽  
Impact Zones

The increase of cosmic radiation on 23 February 1956 by solar radiation exhibited in the first minutes a high peak at European stations that were lying in direct impact zones for particles coming from a narrow angle near the sun, whilst other stations received no radiation for a further time of 10 minutes and more. An hour later all stations in intermediate and high latitudes recorded solar radiation in a distribution as would be expected if this radiation fell into the geomagnetic field in a fairly isotropic distribution. The intensity of the solar component decreased at this time at all stations according to the same hyperbolic law (~t–2).It is shown, that this decreasing law, as well as the increase of the impact zones on the earth, can be understood as the consequence of an interstellar magnetic field in which the particles were running and bent after their ejection from the sun.Considering the bending in the earth's magnetic field, one can estimate the direction of this field from the times of the very beginning of the increase in Japan and at high latitudes. The lines of magnetic force come to the earth from a point with astronomical co-ordinates near 12·00, 30° N. This implies that within the low accuracy they have the direction of the galactic spiral arm in which we live. The field strength comes out to be about 0·7 × 10–6gauss. There is a close agreement with the field, that Fermi and Chandrasekhar have derived from Hiltner's measurements of the polarization of starlight and the strength of which they had estimated to the same order of magnitude.

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