Méthode pour produire des faisceaux rectilignes de matière à l'intérieur d'un espace fermé au sein duquel règne un vide poussé

摘要

923,332. Nucleonics. EUROPEAN ATOMIC ENERGY COMMUNITY (EURATOM). Jan. 19, 1962 [Jan. 21, 1961], No. 2122/62. Class 39 (4). A method of producing, within an enclosed space at a high vacuum and from a substance which is gaseous at ambient temperature, a straight beam of substance which has a density higher than 10-10 g./c.c., the beam being cylindrical and having small transverse dimensions relative to its length, comprises effecting a controlled condensation of the gaseous substance in a reservoir outside the enclosed space and, when the drops thus formed have reached appropriate dimensions, injecting the mixture of drops and gas towards the enclosed space under such conditions that the stream of drops is separated to a substantial extent from the gas and is then introduced into the enclosed space. In Fig. 1, the main chamber 1 has one end connected to an enclosed space 2 which is cooled by boiling liquid hydrogen and in which is placed an auxiliary reservoir 3; at its other end the main chamber is connected to a terminal chamber 4, and both chambers are evacuated through ducts 5 and 6. The auxiliary reservoir 3 can be connected to hydrogen and tritium reservoirs through valves 7, 8 and can communicate with the remainder of the apparatus through a quick-acting valve 9. The reservoir 3 is initially filled with tritium (e.g.t o a pressure of 10-1 mm.) and then placed in communication with the hydrogen supply which allows the hydrogen pressure to rise for a short time above the pressure corresponding to the threshold of condensation around electric charges and then to fall slightly below the threshold, Fig. 2 (not shown). Whilst the pressure is above the threshold, drops form around ions produced by the radio-activity of the tritium, and afterwards the drops start to increase in size. When the drops reach the required size, e.g. after 0.1 second, the valve 9 is opened to allow a stream of gas and drops to be injected towards the main chamber. Two collimators 10, 11 connected through tubes 12, 13 to vacuum pumps enable most of the gas to be removed from the stream before it reaches the main chamber. If a gas column is required in the centre of the main chamber the stream of drops can be evaporated in situ by electron bombardment. The density of the stream may be about 10-6 g./c.c. using drops of about 10-3 cm. in diameter.