LETTERS TO THE EDITOR

SOME REMARKS ON THE COLLECTION “PROBLEMS OF MODERN PHYSICS—RADIO EMISSION OF THE SUN AND THE GALAXY,” THIRD SERIES, ISSUE 15, 1951

At the present time, studies of solar and cosmic radio noises have developed very widely. It may be assumed that, as a result of these studies, new substantial results will be obtained in astronomy, radiophysics, and meteorology. Therefore the publication of collections of abridged translations and abstracts of foreign periodical literature on this question should be welcomed.

However, the collection named has a number of shortcomings. A number of abstracts and translations do not reflect the main results of the work, but contain secondary conclusions from them.

Thus, for example, in the paper by Appleton and Hey, “Solar Radio Noise,” published in Phil. Mag. 37, 73–84 (1946), as is known, the spectrum of solar radio noise at the surface of the Earth is of greatest interest. It is indicated that the maximum intensity is observed at a wavelength of 4.7 m and that the long-wavelength part of the spectrum is distorted by the influence of the ionosphere. A connection is noted between bursts of solar radio noises and absorption bursts in the $D$ layer of the ionosphere. Instead, in the abstract of the article, emphasis is placed on the calculated part, from which it follows that, in observations by radio amateurs (which are only of historical interest), noises of very high intensity could have been detected. On the main result only the following remark is made at the end of the abstract: “The intensities of the Sun’s radio emission received on Earth at different wavelengths have also been compared. The authors (Appleton and Hey) believe that long-wavelength radiation (beginning at 5 m) is weakened by absorption in the ionosphere.”

From Dicke’s paper, “Measurement of Thermal Radiation at Centimeter Wavelengths,” Rev. Scient. Instr. 17, 268–275 (1946), only a qualitative estimate of the modulation method is given; the quantitative relations given in the paper are not presented; the thermodynamic model, which is the theoretical basis of the radiometer, is not described. Instead, a considerable place in the abstract is allotted to the compensation method, which is not only not expounded by Dicke, but is not even mentioned by him. Let us note that the surname of the author of the abstracted paper (Dicke) has been translated incorrectly (Daik). In speaking of the radiometer, it was necessary to mention the article by Dicke et al., “Measurement of Atmospheric Absorption with the Aid of a Centimeter Radiometer,” Phys. Rev. 70, September 1946, which considerably broadens the conception of the modulation method.

In some abstracts the results of investigations are presented incorrectly; thus, in the abstract of the note by Legg and Yabsley, “Burst of Solar Radio Noise at Frequencies 600 and 1200 Mc/s,” Nature, No. 4095, April 1948, it is said:

“A report on powerful bursts of radio emission observed on October 4, 1947, at wavelengths of 50 and 25 cm, during which the effective temperature reached, respectively, \(30 \cdot 10^6\) and \(6 \cdot 10^6\) K.” In fact, the note says that “in the absence of spots on the Sun, the effective temperature at a frequency of 600 MHz is \(0.5 \cdot 10^6\) degrees K, and at a frequency of 1260 MHz—\(0.1 \cdot 10^6\) degrees,” and further: “On October 4, during a strong flare, the effective temperature at frequencies of 600 and 1200 MHz increased 30-fold in comparison with the normal level.”

The abstract journal is not sufficiently complete. For example, some works published in the journal Nature in 1948 are abstracted, while others are not. A number of important periodicals have been omitted from consideration (for example, Quarterly Bulletin on Solar Activity).

An abstract journal must not only correctly present the substance of the works, but also accurately enough render the titles of these works. From this point of view, the phrase “Solar radio noise” (solar radio noise) should not be translated as “radio emission of the Sun.” It is also desirable to give the authors’ surnames and the titles of articles, along with the translation, in the original transcription.

V. A. Baranulko