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Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 CONT

In addition to their bounce motion, the trapped particles also drift azimuthally(in longitude) : ions to the west, electrons to the east. It is this drift motion that creates the ring current. The two-dimensional surface that these particles define through their combined bounce and drift motions is known as a "drift shell" or "L shell".  2, record 1, English, - drift%20shell

Record 1,  Textual support,  French

Record 1,  Textual support,  Spanish

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 CONT

Linear proton accelerators. The design principle applied in linear accelerators for protons was originated by Luis Alvarez at Berkeley in 1946. It is based on the formation of standing electromagnetic waves in a long cylindrical metal tank, or cavity, as it is sometimes called. In the design that has been adopted, the electric field is parallel to the axis of the tank. Most of these accelerators operate at frequencies of about 200 MHz. During the time required for a proton to traverse one of these tanks, the accelerating electric fields undergo many reversal of direction. In Alvarez’ design, the decelerating effect of the field during the intervals when it opposes the motion of the particles is prevented by installing on the axis of the tank a number of "drift tubes".... The electric field is zero inside the drift tubes, and if their lengths are properly chosen, the protons cross the gap between adjacent drift tubes when the direction of the field produces acceleration and are shielded by the drift tubes when the field in the tank would decelerate them. The length of the drift tubes are proportional to the speeds of the particles that pass through them.  1, record 2, English, - linear%20proton%20accelerator

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 CONT

(...) ce n'est qu'avec le développement des générateurs de puissance radiofréquence (rf) que Luis W. Alvarez a été en mesure de proposer (...) la structure qui est encore utilisée aujourd'hui dans les versions modernes de l'accélérateur linéaire à protons. Une cavité résonnante cylindrique est excitée à une fréquence d'environ 200 MHz (...) Il s'agit d'une onde électromagnétique caractérisée par un champ magnétique perpendiculaire à la direction de propagation et un champ électrique possédant une composition parallèle à la direction de propagation. Pour que les protons ne soient soumis au champ électrique que pendant une phase accélératrice, des tubes de glissement, formant cage de Faraday pour les particules les traversant, sont disposés suivant l'axe de la cavité. (...) La longueur des tubes croît à mesure que la vitesse des protons augmente.  1, record 2, French, - acc%C3%A9l%C3%A9rateur%20lin%C3%A9aire%20%C3%A0%20protons

Record 2,  Textual support,  Spanish