Astounding Science Fiction (British Edition), April 1944 — page 15: what you’re looking at

Machine-transcribed from the original scan — historical spelling and the odd misread are preserved.

RECOIL 13 go flinging electrons off the Station in basketful after basketful, and the next bird that drops a ship on the landing stage is going to spot-weld himself right to the South end of Venus Equilateral. It wouldn’t be long before the Station would find itself being pulled into Sol because of the electro- static stress—if we didn’t run out of elec- trons first!” _ “T hardly think that we’d run out—but we might have a tough time flinging them away after a bit. Could be that we should blow out a fist full of positrons at the same time?” “Might make up a concentric beam and wave the positive ions at the target,” said Channing. “Might help.” “But this space-charge effect. How do we get around that?” “Same way we make the electron gun work. Fire it off at a devilish voltage. Run your electron velocity up near the speed of light; the electrons at that speed will acquire considerable mass, in accordance with Lorenz’s equation which shows that as the velocity of a mass reaches the speed of light, its mass becomes infinite. With a healthy mass built up by near-light velocities, the electrons will not be as easy to deflect. Then, too, we can do the damage we want before the charge can be built up that will deflect the stream. We ram ’em with a bundle of electrons moving so fast that the charging effect can not work; before the space charge can build up to the level re- quired for self-nullification of our beam, the damage is done.” “And all we need is a couple of trillion volts. Two times ten to the twelfth power. Grrr.” “I can see that you'll need a tablecloth,” said Arden. “You birds can think better over at Joe’s. Come along and feed the missus, Don.” Channing surveyed the instrument again, and then said: “Might as well, Walt. The inner man must be fed, and we can wrangle at the same time. Argument assists the digestion—and vice versa.” “Now,” said Channing, as the dishes were pushed aside, clearing a space on the table. “What are we going to do?” “That’s what I’ve been worrying about,” said Walt. “Let’s list the things that make our gun ineffective.” “That’s easy. It can’t dish out enough. It’s too dependent upon mobility. It’s funda- mentally inefficient because it runs out of ammunition too quick, by which I mean that it is a sort of gun with antiseptic bullets. It cures its own damage.” “Prevents,” said Arden. “All right, it acts as electrostatically.” “About this mobility,” not quite agree with that.” “You can’t whirl a hunk of tube the size and weight of a good-sized telescope around fast enough to shoot holes in a racing space- ship,” said Channing. “Especially one which is trying to dodge. We’ve got to rely upon something that can do the trick better. Your tube did all right following a meteor that runs in a course that can be predicted, be- cause you can set up your meteor spotter to correct for the mechanical lag. But in a spaceship that is trying to duck your shot, you'll need something that works with the speed of light. And, since we’re going to be forced into something heavy and hard- hitting, its inertia will be even more so.” “Heavy and hard-hitting means exactly what?” i “Cyclotron or betatron. One of those dingusses that whirls electrons around like a stone on a string until the string breaks and sends the stone out at a terrific speed. We need a velocity that sounds like a con- gressional figure.” “We've got a cyclotron.” “Yeah,” drawled Channing. “A wheezy old heap that cries out in anguish every its own. shield, said Walt, “I do -time the magnets are charged. I doubt that we could move the thing without it falling apart. The betatron is the ticket.” “But the cyclotron gives out with a lot more soup.” “If I had to increase the output of either one, I could do i@M lot quicker with the betatron,” said Channing. “In a cycotron, the revolution of the electrons in. their accelera- tion period is controlled by an oscillator, the voltage output of which is impressed on the D chambers. In order to speed up the elec- tron stream, you’d have to do two things. One: Build a new oscillator that will dish out more power. Two: .Increase the strength of the magnets. “But in the betatron, the thing is run differently. The magnet is built for A.C. and the electron gun runs off the same. As your current starts up from zero, the electron gun squirts a bouquet of electrons into a chamber built like a pair of pie plates set rim to rim. The magnet’s field begins to build up at the same time, and the resulting increase in field strength accelerates the elec- trons and at the same time, its increasing Ccomiclbooks.c©