"Strange?" Approaching, Senior Brother Yan stared at the computer screen for a long time, his brows furrowed slightly, "...... It's really strange, isn't the experiment we did a collision of the 1-10GeV energy segment? Why is it that all the data is on 1TeV? ”

As he spoke, Senior Brother Yan cast an inquiring glance at Professor Greer.

The conversion between TeV and GeV is 1:1000, which is equivalent to the particle beam in the collider tunnel, and the energy of the collision has reached 1000 GeV. And to find the collision energy needed for the five-quark state particles, 6 GeV is sufficient.

In order to find a particle located in the 6GeV energy region, turn the collision energy above 1000GeV, this is no longer a cannon to fight mosquitoes, it is simply a rocket to hit a fly.

However, hearing Yan Xinjue's question, Professor Grell smiled and explained in a casual tone.

"As I said, the condition of the test orbit is not a formal experiment. As for why it drove so big, you have to understand CERN's love for getting this new toy. If it weren't for the limited budget for this experiment, they would even be ready to show you peers a collision in the 10TeV energy region or more. ”

To put it bluntly, it's showing off.

And it's the kind of show-off of Chiguoguo.

Imagine theoretical physicists and high-energy physics laboratories all over the world with their eyes on this. If you don't take this opportunity to show off, wouldn't you be blind to the billions spent on expanding the track?

If you don't let the particle clusters inside the collider explode, how can you let others know how awesome your machine is?

However, CERN does have the capital to show off, and it is said that in extreme cases, the expanded Hadron Collider can even do 14TeV collision experiments. That is, every particle orbiting in orbit will carry 7 TeV of energy.

How terrifying is this energy?

In many cases, this unit of energy (according to the mass-energy conversion formula) is also used to describe the mass of a particle, for example, the mass of a hydrogen atom is about 1 GeV, and the Higgs particle discovered in 12 years is 125 GeV.

Compared with its peers, the limit of the Shangjing Positron Collider is about 5 GeV, which is a full order of magnitude different from the energy unit TeV.

If you want to catch up with this energy unit, you can only look forward to the completion of the CEPC in Qindao, but that will be ten years later.

“…… I don't mean that the experimental energy section is strange," Lu Zhou's finger almost poked into the computer screen, "haven't you noticed?" Around 750GeV, there is an anomalous impact here. ”

"It's not called an impact phenomenon, it's just a single two-photon signal, but it's a bit strange why it appears in the 750GeV energy region." Professor Grell rubbed his chin, "But strange as it is, this is not unusual, we can always observe some special signals on the ATLAS detector, but the data reflected on the statistical image may just be a 'noise'." ”

"Is this a common situation?" Staring at the anomaly on the screen, Lu Zhou couldn't help but ask.

"It's quite common," Senior Brother Yan nodded, "We don't know more than 1% of all the signals generated by proton beam collisions. So we usually speculate on the conclusions and then verify them experimentally, and if you stay here a lot, you'll get used to it. ”

High-energy physics itself is a very metaphysical thing.

Since the existence below the atomic level cannot be "directly observed", in order to determine the real existence of a particle, a very important metric is involved - confidence.

It's a statistical concept.

In high-energy physics experiments, 3 times the standard deviation is called "sign", more than 3 times is called "evidence", and more than 5 times is called "discovery". While words like "breakthrough" and "major discovery" often appear in the news, most of the time they are just "signs."

Based on this accepted theory, a confidence level of 3 sigma can barely be counted as an "indication".

A temporary feature peak doesn't say anything.

As long as a particle is observed multiple times on different detectors and different colliders through repeated experiments, the particle can only be confirmed as "discovered" when the confidence level of the particle reaches more than 5 sigma on multiple detectors.

Hearing Senior Brother Yan say this, Lu Zhou didn't say anything more.

Soon, the experiment continued.

A series of green dots spread out densely on the image, and most of the dots are concentrated in the area below the 125GeV dividing line.

However, Lu Zhou still couldn't let go of the point where 750GeV appeared, and his attention was still limited to that section of the energy area.

Then at this moment, suddenly another point jumped to the position of the 750GeV energy range.

At this moment, Lu Zhou's heart suddenly moved, and he looked at Professor Grell next to him and asked, "What about the data on the CMS detector?" ”

There are many detectors in one orbit, among which the ATLAS and CMS detectors are the most sensitive, and are even used to find dark matter.

There is a very simple way to test whether the anomaly he found is an illusion, and that is to observe the same phenomenon by two detectors at the same time.

Hearing Lu Zhou's question, Professor Grell was slightly stunned and replied with a puzzled expression.

“…… The data collected by the CMS detector is in charge of the upstairs lab, and if you're curious, I'll take you there when the experiment is over, but I can't leave it right now. ”

Lu Zhou then asked: "Then will the impact data measured by these trial runs be recorded?" ”

Professor Grell nodded: "Generally speaking, it will be archived, but it doesn't have much reference value, I can give you a copy if you need it, and it's not a confidential content anyway." However, I have to warn you that it is impossible for you to cite this kind of unpublished experimental data in your paper. ”

Standing next to him, Senior Brother Yan asked curiously, "What did you find?" ”

Lu Zhou thought about it, and finally insisted on his point of view, and said: "I always feel that the data of the 750GeV energy area is a bit problematic. Even from a statistical point of view, it feels a bit far-fetched to describe this apparent bulge as a random event. ”

Senior Brother Yan joked: "From the perspective of a mathematician? ”

Lu Zhou: "Sort of. ”

Senior Brother Yan sighed and said, "I know that your research direction is mathematical physics, but I have to remind you that although mathematics is an important tool for studying theoretical physics, not all physical phenomena must conform to mathematical laws. From a theoretical physics point of view, the number 750 GeV is ...... It's too heavy, and the Higgs particle is only 125 GeV. You may think you've discovered a new particle, but it seems to me that it's just a two-photon signal, and there may not even be a collision at all. ”

Patting Lu Zhou on the shoulder, Senior Brother Yan continued, "Don't worry about the energy region after 10GeV, what we are looking for this time is a five-quark particle. If it's because of OCD, you can rest assured that you won't see 750GeV again in a while. ”8)