Gamma Rays Of Radium Research Articles

High Frequency Rays of Cosmic Origin

It was as early as 1903 that the British physicists, McLennan and Burton(1) and Rutherford and Cooke(2) noticed that the rate of leakage of an electric charge from an electroscope within an air-tight metal chamber could be reduced as much as 30% by enclosing the chamber within a completely encircling metal shield or box with walls several centimeters thick. This meant that the loss of charge of the enclosed electroscope was not due to imperfectly insulating supports, but must rather be due to some highly penetrating rays, like the gamma rays of radium, which could pass through metal walls as much as a centimeter thick and ionize the gas inside.

High Frequency Rays of Cosmic Origin

It was as early as 1903 that the British physicists, McLennan and Burton(1) and Rutherford and Cooke(2) noticed that the rate of leakage of an electric charge from an electroscope within an air-tight metal chamber could be reduced as much as 30% by enclosing the chamber within a completely encircling metal shield or box with walls several centimeters thick. This meant that the loss of charge of the enclosed electroscope was not due to imperfectly insulating supports, but must rather be due to some highly penetrating rays, like the gamma rays of radium, which could pass through metal walls as much as a centimeter thick and ionize the gas inside.

Possibilities of Deep X-Ray Therapy with the Coolidge Water-Cooled Tube and Heavier Transformers

THE purpose of this paper is not to describe any new form of therapy, but to present the apparatus and technic of a more intense application of X-rays than has hitherto been employed in treatment. Treatment of deep-seated lesions with X-radiations has progressed markedly within the past few years. The American type of closed, oil-encased transformer superseded the German open-core type; the gas tube was replaced by the hot cathode tube; machines thus came into use which could function continuously over many hours at a potential of two hundred thousand volts and an intensity of four or five milliamperes. The rays emitted were of a longer wave length and far less penetration than the gamma rays of radium, but possessed a beneficial therapeutic action in the field of malignancy and allied conditions, a form of ray therapy being thus developed by which treatment could be rapidly administered over a wide area, including the growth and its lymphatic connections. The search continued for more powerful transformers and for a type of vacuum tube which could carry higher amperage and higher voltage. A year ago Coolidge reported a water-cooled tube which with adequate transformers generates a far more powerful X-ray beam than has as yet been achieved in X-ray manufacture.2 We have been operating a Wappler machine (Fig. 1) functioning at two hundred thousand volts and four milliamperes for a couple of years, with complete satisfaction and uniformly gratifying results. When Coolidge perfected his invention, however, we hastened to install one of his water-cooled tubes for the sake of the heavier output promised. None of the stock transformers on the market appeared to have sufficient capacity to deliver a stable output at this high amperage and voltage; so we appealed to Dr. Waite of the Waite and Bartlett Manufacturing Company of Long Island City, N. Y. Dr. Waite constructed special heavy transformers which have proven most reliable. Working with this system, we have a complete water circulation under forty to fifty pounds pressure; the X-ray tube is kept at an even low temperature during its excitation by the flow of water through a seamless coil of copper pipe behind the tungsten target. A large automobile radiator of copper mesh with an eighteen-inch fan serves to maintain the low temperature of the water system. The X-ray tube is eight inches in diameter. There is a projecting molybdenum pin in the filament spiral which produces a more uniform heat gradient by producing a large focal spot. We have been able to operate this machine at two hundred and fifty thousand volts and fifty milliamperes, but for practical purposes of treatment we use two hundred and forty thousand volts and forty milliamperes. Advantages of the Water-Cooled Tube Comparative electroscopic measurements of this new device and of our old two hundred thousand volt machine prove the former apparatus to possess twenty times the power generated by the old machine.

THE NEW SHORT WAVE LENGTH ROENTGEN-RAY THERAPY

Especially within the last three years the interest of the profession in this country has been aroused by claims advanced for the value of the new deep roentgenotherapy, a method of radiation involving the use of rays of much shorter wave length than have heretofore been available for purposes of treatment. For a decade such physicists as Duane, Dessauer and Coolidge have been seeking means for producing roentgen rays of wave length nearly approximating the shorter gamma rays of radium. Refinements have been reached in the construction of roentgen-ray apparatus, permitting the maintenance of constant very high voltages (from 200,000 to 280,000) delivered at the roentgen-ray tube terminals. Dr. Coolidge has continued the development of his tube until we now have a type of roentgen-ray tube, capable of withstanding more than 200,000 volts at 8 milliamperes in continuous use. The physical and biologic investigations carried on simultaneously in Europe and

The Action of Buried Tubes of Radium Emanation on Neoplasias in Plants

The insertion into an animal tumor of buried capillary glass tubes containing radium emanation presents a comparatively new departure in radium therapy and is undoubtedly destined to play a prominent part in the future development of the whole field of radiotherapeutics. The technique employed on animals and human beings is as follows: Radium emanation, the first active product of decomposition of radium, is an elementary body in a state of a heavy gas, and by means of appropriate apparatus may be collected in capillary glass tubes 3 to 5 mm. long, and 0.25 mm. in diameter. These tubes may be made to contain anywhere between 0.1 to several millicuries of radium emanation each. They are inserted into the tumor tissue by aid of a trocar. The tubes exert a comparatively weak but continuous action on the tissues which lasts for several weeks. The cumulative action of 1 mc. when buried permanently in the tissue is calculated to equal 132 mc. hours. The tissue immediately surrounding the capillary is influenced by the soft beta rays and may become necrotic. Figure 1, A , shows such an area of necrosis in the spleen of a rabbit into which a radium emanation capillary was inserted. A priori it is feasible to anticipate that this necrotic area acts as a filter on the soft rays and the next zone of tissue is then influenced only by the hard gamma rays of radium. In the course of the last two and a half years, the senior writer has used this method extensively in his clinical work. As a general rule the insertion of capillary glass tubes in carcinoma and sarcoma in the human patient is followed by the replacement of the tumor tissue, in the vicinity of each capillary tube, by a connective tissue capsule which wholly encloses the tube. The whole tumor shrinks in size, a process which takes place gradually in the course of six to eight weeks after the insertion of the capillary tubes.

The Action of Roentgen and Gamma Radiations Upon the Electrical Conductivity of Selenium Crystals

Action of Gamma and Roentgen Radiations Demonstrated.---The increase in conductivity of selenium "cells" accompanying the absorption of X-rays has been found characteristic of individual crystals of metallic selenium. A similar effect upon the crystals has been observed to be produced by the absorption of the gamma rays of radium. The fact that a crystal fatigued to gamma rays is fatigued also to X-rays is evidence that the action in the two cases is similar. The indications are that the crystals are approximately twice as sensitive to gamma rays as to X-rays of the type used (L rays of tungsten).New Electro-mechanical Properties.---Increase of mechanical pressure upon a crystal results in an increase of its sensibility both to X-rays and gamma rays. This is exactly the same result, qualitatively, as that secured by Brown in his study of the light effect (Phys. Rev., 4, p. 85)Action of Separate X-ray Frequencies.---Unsatisfactory results obtained in the study of the strong lines of the L radiation of tungsten are thought to be due to the low intensities afforded by the X-ray spectrometer. Another method of attack is being planned.Comparison of the Light, X-ray, and Gamma Ray Effects upon an Isolated Crystal.---Calculations made upon the basis of the energy absorbed indicate that a selenium crystal is most sensitive to gamma rays. The ratios of the change in conductivity to absorbed energy for exposures of one minute are 33.2, 58.5, and 108.9 (Mhos/Joules), respectively.

Variation with Pressure of the Residual Ionization due to the Penetrating Radiation

Residual Ionization in Closed Vessels: Experimental Method.---In order to throw light upon the type of radiation responsible for the residual ionization in closed vessels, the author has measured the ionization in a sphere one foot in diameter for pressures ranging up to 21.5 atomospheres. Any corpuscular radiation not absorbed in the ionization sphere has a penetration at one atmosphere equal to or greater than the product of the dimension of the sphere and the number of atmospheres pressure. A special device was used to compensate for any fluctuations of the battery furnishing the high potential required for saturation. This consisted of two ionization spheres of the same electrical capacity which were connected to the opposite ends of a ten megohm resistance, the mid-point of which was earthed. Connections from the battery were made to the ends of the ten megohms. The final experiments were performed over water to eliminate any effect due to radio-active substance in the soil.Nature of Ionization Curve.---The shape of the ionization-pressure curves gives information as to the process of ionization. A discussion of such curves obtained by other observers has been given in connection with those of the author. The curves obtained in the present experiment give a linear relation. This indicates that the ionization is not due to a soft radiation from the walls of the sphere, but that it is due either to the direct action of a penetrating radiation without any effect produced by secondary $\ensuremath{\beta}$ rays from the gas, or to a secondary, corpuscular radiation from the walls of the vessel. If the latter is responsible for the main portion of the ionization, the experiments indicate that it has a penetration of at least six and one half meters in air at atmospheric pressure.Diurnal Variation.---A few curves obtained during the preliminary observations have been given. Provided that the sky is not cloudy, these indicate the existence of a diurnal variation.Ionization in Air Due to Gamma Rays of Radium.---The ionization in a sphere one foot in diameter has been measured for pressures ranging up to 40 atmospheres. From four to twenty atmospheres a linear relation existed. The change in slope at twenty atmospheres to a value about six tenths of that at lower pressures may be attributed to some of the $\ensuremath{\beta}$ rays having completed their paths. At the high pressures there is a suggestion of an effect due to the secondary radiation from the air.

The Effect Upon the Atom of the Passage of an Alpha Ray Through It

In 1910, by catching at the instant of ionization the positive residues of atoms ionized by X-rays, and by beta and gamma rays of radium, it was conclusively shown(2) that the act of ionization by these agencies uniformly consists in the detachment of a single negative electron from a neutral atom.

The effects of the beta and gamma rays of radium on protoplasm

The effects of the beta and gamma rays of radium on protoplasm

Can the Gamma Rays of Radium be Produced Artificially in an X-Ray Bulb?

ArticlesCan the Gamma Rays of Radium be Produced Artificially in an X-Ray Bulb?F. DessauerF. DessauerFrankfurt-am-MainSearch for more papers by this authorPublished Online:30 Jan 2014https://doi.org/10.1259/arr.1914.0046SectionsPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail About Previous article Next article FiguresReferencesRelatedDetails Volume 19, Issue 4September 1914Pages: 119-154 Copyright © 1914, the British Institute of Radiology History Published onlineJanuary 30,2014 Metrics Download PDF

The Changes which occur in Malignant Tumours on Exposure to the Gamma-rays of Radium

The Changes which occur in Malignant Tumours on Exposure to the Gamma-rays of Radium

Phosphorescence caused by the beta and gamma rays of radium.

1. Various observers have noticed that barium platino-cyanide, after continued exposure to the rays from radium, becomes brown or red, while the phosphorescence excited by the rays falls off considerably. The following observations were made with the object of ascertaining the conditions under which this change occurs. 2. A specimen of Merck’s barium platino-cyanide was recrystallized and obtained in prisms from 3 to 5 mm. long. The crystals were bright canary yellow and showed a pale blue fluorescence by obliquely reflected light.

Phosphorescence caused by the beta and gamma rays of radium.–Part II.

By the study of the-case of barium platino-cyanide, it has been shown that certain forms of phosphorescence or luminescence are due to change of physical state— e. g ., to the passage from the crystalline to the amorphous state, or from one amorphous state to another. The molecular movement required to bring about these changes may be caused— (1) by disintegration produced by mechanical means, as in the crushing or flowing of crystals; (2) by the expulsion of a volatile constituent, as in the dehydration of crystals, the molecular movement which necessarily occurs at the moment of expulsion being taken advantage of by the forces of cohesion to establish new arrangements of the molecules either crystalline or amorphous; and (3) by a condition of excessive vibration and ultimate overstrain set up by a stream of electrons, as in the radium or the cathode rays.