Fifteen kilometers away.

A tall steel frame stands in the vast expanse of snowy fields, looking somewhat out of place for this era—the neat, dense exposed structure, the icicle-laden beams and cables, and the layers of surrounding barbed wire all exude an industrial aesthetic.

Hundreds of people are busying around it, preparing for the detonation.

Since the entire device weighs nearly ten tons, and Hummingbird is at the front line, it was impossible to assemble it in Neverwinter. Instead, the parts were transported to the test site for on-site assembly.

Fortunately, its structure itself is quite simple, and the design took into account the need for disassembly and transportation, so the requirements for workers are not high.

This is also the difference between "Radiance of the Sun" and other weapons—even after the site and equipment are set up, it still takes a day or two to complete the final preparations.

At this moment, Roland and Anna are standing on top of the tower, directing the assembly work.

"Next is core component number three, pay attention to the direction of the interface, be careful of bumps!"

"Everyone listen to my command! Three, two, one!"

Following the foreman's call, a silver-white cylinder was slowly pushed into the device.

Only after this step was completed did Roland slowly breathe a sigh of relief.

Inside the cylinder is the main energy source for this test explosion—two separately packaged U-235 cylinders, each weighing twenty kilograms. When the two are combined, they will provide a total charge mass of forty kilograms. This value is lower than the critical limit of fifty-three kilograms, and theoretically a violent fission reaction will not occur, but as he said before, criticality is not a fixed value.

Shape, temperature, pressure, and other conditions can cause this value to change, which is why "nuclear weapons" that rely solely on stacking materials have almost no practical value. For example, fifty-two kilograms of U-235 in a spherical state may seem stable, but it is actually a volcano about to erupt. Even a slight impact or vibration could cause it to exceed the critical point.

Similarly, using multiple small uranium blocks is safer, but it also makes the detonation difficulty increase exponentially—when several uranium blocks are combined into one, its overall size can indeed exceed the critical point, but the high temperature generated by the fission reaction will cause the uranium blocks to expand rapidly, indirectly reducing their density, and the violent explosion will push the raw materials away, thereby interrupting the reaction.

In short, a reasonable configuration must not only allow the uranium element to reach criticality, but also maintain this state for as long as possible to exert the power that the fission reaction should have.

The reason why the gun-type configuration is called gun-type is that its principle is very similar to that of ancient muskets. Through the detonation of explosives, one uranium block is pushed violently towards another uranium block. Under tremendous pressure, the density of the uranium blocks will increase rapidly, and even if the mass is slightly lower, it can still cross the critical point.

After the outer shell of the device was connected, Anna personally inserted a package with a radiation source warning sign into the reserved tail interface.

That was also the last key component of this test explosion.

For a moment, Roland felt like he was being pricked on the face, and even his breathing paused for half a beat.

"Polonium-Beryllium Neutron Source."

Just like its name, it can provide a large number of free neutrons for fission, and it is also the most direct way to reduce the critical value. Inside the can-like metal container, there is a row of hollow spheres—each sphere is about the size of a ping pong ball, with a marble-like polonium ball at its core, wrapped tightly in gold foil, and around it is a honeycomb-shaped ring of beryllium flakes.

When the uranium blocks collide, they will also smash this small can at the bottom of the "barrel". All the hollow spheres will be crushed thinner than paper by the violent explosive gas. After the gold foil breaks, the beryllium flakes will be closely attached to the polonium ball, fully accepting the alpha particles released by the latter, and then ejecting several times the number of neutrons.

These neutrons will participate in the fission reaction of U-235. If you are lucky, you can consume several more percent of the raw materials before the reaction stops, greatly increasing the power of nuclear weapons.

Since the half-life of Polonium-210 is only 138 days, providing a replacement interface is an essential design. In addition, leaving the neutron source in the weapon for a long time is also extremely dangerous. After all, polonium-beryllium can spontaneously emit neutrons as soon as they come into contact. If the gold foil is damaged, the consequences will be unimaginable.

After the polonium-beryllium neutron source is installed in the principle device, it changes from a gentle, harmless object into a monster that could swallow everyone on site at any time.

Although Roland knew that his feelings were just an illusion, and it was impossible for a person to capture changes in the number of neutrons in the environment, he still subconsciously slowed down his breathing.

At this step, the principle device was officially completed with all the preparations before detonation.

Anna took his hand主动.

"Give the order."

In the other party's peaceful and steady gaze, Roland nodded slightly.

No matter what the result, the Radiance of the Sun plan has finally reached this point.

And after this step is taken, mankind will move into a new field.

He looked at his guard Shawn, "Pass my order, notify the command post, six-hour countdown to ignition!"

"Yes, Your Majesty!"

"6:00"

"Oooooooo—————Oooooooo—————Oooooooo—————Oooooooo——————"

"Device No. 1 has entered the ignition standby phase. Repeat, device No. 1 has entered the ignition standby phase. Please field personnel immediately pack up your belongings and leave the field in an orderly manner according to the exercise plan! Note, this is not a drill. The test site will be closed in one hour. Everyone must evacuate to a safe area before this time!"

Soon, the evacuation notice and the alarm sounded throughout the site.

"Quick, quick, everyone gather in the open space in front of the tower, don't leave anyone behind!"

"The second construction team reports the number, one, two, three..."

"The test platform gate is sealed!"

"The God's Punishment Witches squad is all present, start leading the evacuation."

The quiet snowfield seemed to boil, and the shouts of people and the repeated alarm sounds echoed each other, and the atmosphere became tense and solemn for a while. Everyone knew in their hearts that they were about to witness an unprecedented experiment.

"3:00"

In the command post, Roland and Anna took out two keys and opened the cover of the console together.

As the switches were pressed one by one, the green lights on the panel lit up in sequence.

"The main cable is being powered!"

"Mystery Moon One is working normally, and the load is rising steadily."

"Now switch to line one."

"Understood, line one is connected, and the power supply to the principle device is normal!"

The observer loudly reported the operation of the detonation system. When the last green light lit up, it meant that the current had been transmitted to the high platform fifteen kilometers away through multiple step-up relays.

"1:00"

The alarm also sounded in the sky above the command post, which meant that only the last hour remained for the ignition program.

The shelter doors and windows were all closed, and the oil lamps were extinguished one by one to avoid accidents caused by vibration.

Neverwinter's high-level officials entered a special observation room. According to Roland's instructions, its outer facade was built into a trapezoid to better resist the shock wave, and the inner end was deepened to accommodate the huge body of the Primal Carrier.

Pasha and other Taquila witches had been waiting for a long time.

"0:15"

It was getting dark.

The last round of urgent alarms finally arrived.

Whether it was high-level officials, soldiers, or workers, they all put on black sunglasses to resist strong light according to the previous exercise content.

Although most people did not understand why they had to wear these vision-obstructing glasses on this dark and snowy day.

Isn't this making it impossible to see anything?

"0:05"

"Countdown, five minutes!"

When the announcement sounded again, the scene had become silent.

All communication and discussion had ceased, and everyone stared intently at the dark front, involuntarily holding their breath.

"Three-minute countdown!"

Roland felt fine sweat breaking out in his palms.

Anna smiled and looked at him, gently holding his hand.

"One-minute countdown!"

Another hand reached over, and then five fingers overlapped.

"Ten-second countdown!"

"Nine!"

Although it was a pity that he couldn't press the detonation button himself, Roland knew that this long road of historical facts had just begun.

"Three!"

"Two!"

"One!"

"Detonate!"

The distant snowfield was quiet, as if nothing had happened—time seemed to freeze at this moment, as if it had been a long time, and as if it was only a short moment.

Then, an extremely dazzling blue light bloomed from the horizon, instantly tearing apart the darkness in front of them!