Into Unscientific

As the only experimenter in this experiment who was on the "first site" of the equipment, that is, on the other side of the glass.

Wang Ganchang's mission this time is undoubtedly dangerous and arduous.

The so-called danger naturally refers to the matter of suppressing the gate.

You must know that the gate of the tandem electrostatic accelerator is not the gate in the traditional concept of later generations. There is no situation where [even the external squeeze release will jump] - it is loaded with gradient power.

The existence of the gradient difference will cause the entire accelerator to have a functional current trajectory during the acceleration process, rising and falling together like a wave.

The gradient impulse during the wave peak will cause the gate to rebound instantaneously, so someone must press it during the experiment.

This belongs to the limitations of the technology of the times. Not to mention the rabbits, even the University of Cambridge and CERN must operate this way.

No matter how unreasonable you criticize it with the eyes of later generations, this is still an established fact that happened in history.

Even if the current period is 23 years later, when the rabbits have developed a 30 MeV sector-shaped focusing cyclotron, they will still have to manually suppress the gate when starting it up.

Fortunately, these devices are relatively sturdy, and there have been no accidents in China. At most, there have been burns due to improper protection. Although currents of this magnitude are limited by insulation equipment and will not leak, the temperature of the coils is still It's very tall and will melt if you get closer.

And besides this dangerous mission.

The remaining difficulty is.

Wang Ganchang must immediately remove the colliding target as soon as the collision is completed for further analysis.

Two minutes later.

Under the watchful eyes of everyone, Wang Ganchang placed the target on a slot through the glass.

This is somewhat similar to the action of inserting and taking out a power card when people check into a hotel in later generations, but the "room card" at this time is much larger than the real room card.

at the same time.

In the operation room, Zhao Zhongyao and others also came to the operation station on the left and started to get busy:

"Xiao Zhou, go and keep an eye on the sensor!"

"Xiao Wang, turn on the track detection system!"

"Jian Wei, take charge of the power supply!"

"Comrades from the calculation team can start data fitting - if you need to use a computer, report it as soon as possible!"

"No, no, Director Zhao, Comrade Jingrun and Comrade Yu Yu are all here. Why do you need a computer?"

While Zhao Zhongyao and others were turning on their phones, Cheng Kaijia also explained some common sense to Lao Guo Lijue and others:

"Gong Guo, factory director, teachers and the others are conducting particle trajectory analysis now. The socket where Comrade Wang Jing placed the target is the electromagnetic shower detection equipment."

"In addition, there are two silicon detectors inside the collider. They will import the data to a multi-transistor monitor. Through analysis, a large amount of data can be obtained quickly."

"The time interval between collisions in our accelerator is 25ns, which is 40MHz. If nothing else, it can produce thousands of drawings."

Hear this.

Xu Yun on the side also nodded.

As everyone knows.

In terms of steps, the particle collider can be roughly divided into three parts:

Produce particles, accelerate particles, and analyze particles.

There are many methods for producing particles, mainly divided into electron sources and ion sources.

The electron source is heating, photoelectric effect, field emission or secondary emission - it was the field emission principle that Xu Yun used in the 1850 copy.

As for ion sources, there are quite a few, including negative ion sources, positron sources, antiproton sources, neutron sources, etc.

Accelerating particles mainly relies on magnetic fields and electromagnetism. The first difficulty is the acceleration length, which is the strength of the pipe, and the second is focusing.

Among the three modules, the most technical one is actually the third one, which is analyzing particles.

In 2023, when Xu Yun traveled back in time, the technology for analyzing particles was already very mature.

For example, CMS has two levels of frequency reduction, which can quickly judge the value of events, filter boring collision events, and screen valuable collision events.

This frequency reduction technology is also called Trigger. The two-level Trigger can reduce the frequency to 100kHz and 1kHz respectively.

In addition, there are multi-filament proportional chambers, drift chambers, etc. The drift chamber is used in the spectrometer experiment on the Yanjing Electron Positron Collider in China.

But at this time, the technology is relatively primitive.

For example, the tandem accelerator in front of everyone.

It uses silicon semiconductors as the detection sensor because this material can survive the large amounts of radiation in particle collisions and provide high-precision position measurements.

The basic structure of this sensor is the p-n junction common in semiconductor devices. This structure was discovered on March 6, 1940.

All the students who have tutored me in this life should know this.

When an external voltage is applied to the p-n junction, a depletion layer will be generated inside the p-n junction, and there will be an electric field in the depletion layer.

When a high-energy charged particle passes through the depletion layer, it ionizes the lattice atoms of the p-n junction and generates positive and negative charges that can move freely.

These positive and negative charges move to the edge of the p-n junction under the action of the electric field, so they can be collected to generate signals.

Silicon detectors are usually used to detect the "path" traveled by particles. If an external magnetic field is applied at the same time, the silicon detector can detect the deflection angle of the particles in the magnetic field, and then calculate the particle momentum.

But this is just one of the modules for analyzing particles.

The track detection system combined with the magnetic field can detect the momentum of particles, but the detection of particle energy requires another detection system, which is a calorimeter.

High-energy electrons or γ photons will produce electromagnetic showers in the medium. The total energy loss of secondary particles is proportional to the total energy of the incident particles. The total energy loss of the particles can be determined by collecting the total energy loss.

The hadron calorimeter uses the principle that hadrons will produce complex hadron showers in the medium, and obtains the energy of the incident hadrons (also including a small amount of electromagnetic showers) by measuring the deposition energy of secondary particles in the hadron shower process. But I don’t know if this tandem accelerator in Cambridge can detect it, so let me put it here to prevent being slapped).

The calorimeter material used in this tandem accelerator is an inorganic scintillation crystal such as lead tungstate, which can only detect part of the energy in the shower, which is far inferior to later CeF3 crystals or lutetium silicate.

But there is no way, the times are limited - this is already the TOP1 device in the world.

If you want the rabbits to produce equipment of this level on their own, it may not be enough in 15 years without Xu Yun's time travel. It will only be possible to produce it in 20 years.

His eyes returned to reality.

After particle analysis begins.

Everyone at the scene was very smart and didn't say anything. Instead, they took the initiative to go to the other side and pulled up the bar chairs and sat down.

Some people simply leaned on their chairs to relax.

Some people stared intently at the console.

Others took out books such as "Spring and Autumn" and "Quotations of Great Men" from their bodies and read them, many of which were hand-copied.

About twenty minutes passed.

A lesbian with short hair walked over quickly. This person was no stranger to Xu Yun. She was the famous female academician Wang Chengshu in later generations:

"Factory Director, Director Guo, the chart is out!"

Li Jue and others were shocked when they heard this. The group stood up from their seats almost at the same time and followed Wang Chengshu towards the operating table.

At this time, Zhao Zhongyao was reading a report at the operating table. When he saw everyone coming, he pointed towards the table and explained:

"The copy of the report is over there. The content is the same as mine. There are seven or eight copies printed in total. You can allocate them among yourself and read them."

Upon seeing this, Li Jue quickly stepped forward, quickly picked up the document, looked at it a few times, and then thrust it back to Lao Guo:

"Fuck, I'm blind!"

Lao Guo's mouth twitched:

"."

Then Lao Guo took the stack of copies and simply read through them.

Although he is not an expert in particle physics, he has studied strange perturbation theory and can still understand some basic particle information.

"0.51MeV should be the trajectory peak of electrons."

"1.83MeV, it looks like a Σ particle? It's just that the magnitude difference is too big, I don't know if it's negative."

Seeing this, Xu Yun couldn't help but poke his head forward and quickly gave the answer:

"It's a positive Σ particle."

Lao Guo was suddenly startled and asked subconsciously:

"Xiao Han, how can you tell this?"

"Look here."

Xu Yun smiled and stretched out his hand, pointed at a certain place on the report, and explained:

"Probably around July 1954, Mr. Murray Gell-Mann and A. Pace jointly submitted a paper on singular numbers at the Glasgow Conference, and concluded from experiments that Δ/= in weak interactions 1/2 selection rule.”

"You see, there is a certain degree of offset in the wave crest here, and the offset is exactly about 1/2 of the previous section."

"So according to the variant derivation of the selection rule, it is obvious that the center of charge should also be +1/2, which is a positively charged particle."

"Since the particle is positively charged, it is obviously a positive Σ particle."

"Xiao Han is right."

Hearing Xu Yun's words, Zhao Zhongyao nodded quickly, with a hint of emotion in his eyes:

"Gell-Mann's theory can be regarded as his famous work. I met him once when I was observing nuclear physics experiments at Yale University. He showed great talent at that time."

"At that time, Yale University also offered me a treatment, saying that if I stayed at Yale University, they would immediately arrange for Murray to be my graduate student - it is said that this was Murray's own opinion."

"Twenty years have passed in the blink of an eye, and Murray is almost more famous than me. But based on what I know about him, odd numbers are not the upper limit of his abilities."

"Maybe in a few years, he can make some big news. Maybe he can finally leave his name in history? Aha!"

The speaker has no intention, the listener has intention.

At this time, Zhao Zhongyao probably just heard the name of an acquaintance and had some memories, but Xu Yun on the side thought of many things.

The relationship between Gell-Mann and Zhao Zhongyao is not Zhao Zhongyao’s favor, but Gell-Mann’s own words and recorded by John Schwartz in “Elementary Particles and the Universe: A Tribute to Murray Gell-Mann” Content.

Mr. Zhao Zhongyao was already well-known in the international scientific research circle around 1930. After the victory of the Anti-Japanese War, he went across the sea to get parts for the accelerator.

During the second time, he traveled around and spent a lot of time at MIT, Caltech, and Yale University.

Gelman was admitted to Yale University when he was 14 years old. When Zhao Zhongyao was studying in the United States, he was about to graduate from his undergraduate degree, so he came up with the idea of ​​studying for graduate school under Zhao Zhongyao's name.

At that time, Zhao Zhongyao actually liked this young man quite a lot, and he often gave him some cooking tips.

It was a pity that Zhao Zhongyao was destined not to stay across the sea at that time, so Gelman and Zhao Zhongyao ultimately missed this master-disciple relationship.

in the original history.

Zhao Zhongyao passed away in 1998. Gelman did not know the news at the first time, but in the year after Zhao Zhongyao passed away, Gelman flew to China to pay homage to the old man.

However, what Xu Yun was thinking about at this time was not the regret that Zhao Zhongyao "missed" a top student who was ranked in the top 50 in the history of physics, but was lamenting Zhao Zhongyao's choice.

Facing the conditions offered across the sea at that time, Zhao Zhongyao still resolutely returned to China. To be honest, most people really couldn't make this determination.

And Xu Yun has no doubt that even if Zhao Zhongyao knew about Gell-Mann's future achievements in 1947, he would still choose to return to his homeland.

Although it may sound a bit gross, some people's hearts are really born red.

While Zhao Zhongyao was speaking, Wang Ganchang, who had completed his task from the equipment room, also happened to return to the operation room:

"Teacher, how are the analysis results?"

Upon hearing this, Zhao Zhongyao handed him another copy on the table:

"The results have just come out, and I'm still looking at them. You came just in time. Let's analyze them together."

Upon hearing this, Wang Ganchang immediately took the manuscript, looked at it for a few times and quickly raised his eyebrows:

"1.83 MeV? We detected positive Σ particles for the first time?"

Obviously, Wang Ganchang also judged the electrical properties of the particles at a glance.

But it’s normal to think about it. After all, the first anti-Σ particle in human history was discovered by Wang Ganchang himself. It would be strange if he couldn’t see it.

Therefore, everyone did not take it seriously and looked at it again.

Compared with the first page of the report, the content of the second page is slightly more "unofficial" - this report did not detect any particles.

Then the same goes for the third one.

The proton peak appears in the fourth part.

After more than thirty reports, everyone's main discovery still stops at positive Σ particles.

However, Zhao Zhongyao, Wang Ganchang and others did not show disappointment or impatience on their faces.

There are a total of 132 modules on the silicon detector, and each module can detect 47 pixel positions. It is impossible for the particles after impact to be evenly scattered on every pixel, so it is normal to have gap reports.

At that time, Wang Ganchang and others analyzed more than 40,000 pictures before they found the anti-Σ particle.

About ten minutes passed.

Seeing that everyone was busy working but he had nothing to do, Li Jue couldn't help but rubbed his hands and asked Zhao Zhongyao:

"Old Zhao, all the comrades are doing things, and I'm the only one watching the show without doing anything. Isn't this inappropriate? Do you think there's anything I can do to help?"

"I'm not bragging. When we were young, Mr. Li was a well-known young man from all over the country. Even now, he can be regarded as a technical leader, right?"

Zhao Zhongyao:

"."

Who just said that he was blind?

However, Zhao Zhongyao could understand Li Jue's embarrassment, so he thought about it and picked up a ruler from the side.

I saw him drawing a straight line along the horizontal axis at the vertical axis coordinate of an image on a report, and said to Li Jue:

"Lao Li, do you see this line?"

"In this way, you can take this line and compare it one by one on each page of the report. If you encounter an image with a higher peak than this line, tell me immediately. Is that okay?"

Li Jue chuckled when he heard this, stroked his long beard (it is said that having a beard will give people the image of a wise man), and his chest puffed up:

"No problem, Lao Zhao, I promise to complete the mission!"

Looking at Li Jue who was hurriedly making reports, Zhao Zhongyao couldn't help but shook his head.

Are you still guaranteed to complete the task?

Do you know what line is drawn for you?

If this thread could be broken, the entire theoretical physical model would undergo major changes.

Put it this way.

If Li Jue could find that kind of image, Zhao Zhongyao would immediately take care of all the shaving tasks for the base's more than 700 donkeys next month!

Note:

Today is the anniversary of the unconditional surrender of Xiaozhi. Please remember to put your life aside~