Chatting on the Terrace ④
2025-04-04① “Electron Gun”
Hello!
As the new school year begins, many people are likely working hard in a fresh environment.
There are also some new friends joining us for this “Chatting on the Terrace” series.
Meet Nanonose and Terraru!
These two had the special opportunity to visit some of the deeper, usually off-limits areas of NanoTerasu.
We’ll be sharing their adventures over several installments.
This time, they’re chatting about the “electron gun.”
Let’s see what they’re talking about!
N (Nanonose): Remember the other day, when we got special access to a part of NanoTerasu that people usually can’t enter? That was so cool!
T (Terraru): Yeah, it really was! Apparently, hardly anyone ever gets to go in there.
N: That super straight area… was it called a “linear accelerator”?
There were all sorts of devices lined up.
T: Right, and near the entrance there was something called an “electron gun,” wasn’t there?
The name sounds so cool! They said it’s used to create electrons, right?
N: Yeah, but “creating electrons” doesn’t quite click with me…
So, if you heat a metal called tungsten to about 1000°C, electrons start to gently float up from the surface.
And then, when you apply voltage to those floating electrons, like, 10 billion electrons fly out every second, right?
Ten billion per second… I mean, that number is so huge, I still can’t really grasp it (laughs).
And that piece of tungsten is only about 8 mm in diameter, super tiny.
On top of that, since electrons are replenished from the Earth itself, there’s no need to replace it—how eco-friendly! So modern!
T: Hey, wasn’t that part super interesting?
So, the electrons floating up from the tungsten are negatively charged (−), and even though they’re itching to move toward the positive (+) side in front of them,
there’s this grid-like thing called a “grid” that acts like a railroad crossing gate.
Unless the grid gives a GO signal, the electrons can’t move forward!
It totally reminded me of the starting lights in an F1 race.
N: Oh yeah! And when the electrons pass through this thing called the “buncher,” they get tightly compressed from the sides and top & bottom—
so they become a “bunched beam,” a sort of electron clump, and then they shoot into that long copper pipe, right?
T: Yeah yeah, that part is called the acceleration tube, I think?
From there, the journey of the electrons really starts getting wild…
To be continued