Chapter 155 Brand new proton radius data
Xu Chuan is not aware of his mentor's predicament yet, and he has no time to help others.
Because his own proton collision experiment is about to begin.
Ten days of preparation time is not long. Although CERN does not require him to personally control the proton accelerator to conduct experiments, he needs to analyze the data obtained after the experiment is completed.
The data generated by each operation of the proton accelerator is quite large.
Therefore, Xu Chuan needs a team to assist him in completing this task.
For this reason, he has been looking for people to help these days.
Originally, Senior Brother Qi Xishao Qi was a very good choice, but unfortunately, he had already joined Chen Zhengping's team.
It seems that work has already started.
After thinking about it, Xu Chuan called Senior Brother Lin Fenglin who was far away in Princeton.
He didn't know many people. One of them was Senior Brother Lin Feng, who was also a student of Witten and Chen Zhengping.
There is no way, who told him not to follow the development process of a normal person.
When others join CERN for the first time, they usually join as interns. If they have a job, they join the team as a member of the entire team.
After practicing this way for a while, you can get to know a lot of people.
And he directly presided over a project, even though it was only a small project for CERN.
But no matter how small the project is, experiments in the high-energy physics area still require manpower.
His mentor Witten is not very responsible. It may be that this project is nothing in Witten's eyes, or he wants to train him.
So I just applied for and arranged the collision experiment for him and then let it go.
The rest of the data analysis, press conferences and other tasks were all left to him.
Just tell him to tell him after the experiment is completed.
Therefore, Xu Chuan had to complete the experiment independently from beginning to end.
After inviting Senior Brother Lin Feng over, Xu Chuan frowned and thought about who else he could invite to help him complete this project.
But after thinking for a long time, he couldn't find any suitable candidate.
After his rebirth until now, he didn't know many people, it could even be said to be very few.
There was no way, the time was too short, and he didn't have enough journey to get to know more students of the same age as him.
Although there were many students at Nanjing University, and he knew many from both the mathematics and physics departments, it was a pity that none of these students had enough ability to participate in this kind of experiment.
Needless to say, Princeton. In the past two months since he joined Princeton, he has basically been perfecting the calculation method for the mystery of the proton radius, and he has not had time to make any new friends.
Unable to find enough candidates, Xu Chuan turned his attention to the CERN organization.
CERN lacks everything except people.
This is the world's largest high-energy physics research institution. During the normal operation of the LHC, at least more than 5,000 people work here every day.
Excluding the more than average number of engineers and handymen among these 5,000 people, there are still more than 2,000 physicists.
Physicists who can work at CERN, even if they are just interns, have knowledge of a doctoral degree or above.
At least, there is no need to worry about their lack of ability.
After consulting his mentor Witten, Xu Chuan posted a recruitment announcement to the entire CERN.
The mystery of the proton radius is a popular research direction in today's particle physics community. After the announcement was posted, in less than a day, his mailbox received applications from all over the world.
Of course, those who apply to participate in this project are basically CERN interns, both short-term and long-term.
Some may be to enrich their scientific research experience and learn new knowledge, while others may be for their graduation thesis.
Compared with formal researchers who basically have their own tasks, these interns have a much higher degree of freedom.
Especially those long-term interns, except for the experimental tasks of their own schools or organizations, they spend a lot of time in a state of idleness. They are trying to find their own opportunities in CERN.
Just like Xu Chuan's experiment, many times, teams from all over the world need some "temporary workers" to help them complete some data analysis or other basic work.
These are great exercise opportunities for interns.
Although these applicants were mixed, in any case, Xu Chuan was able to solve the problem of team personnel needs.
All that's left is to make your selection.
After all, it's not suitable for everyone.
After a day of screening, Xu Chuan finally selected three people from the mailbox.
They are interns Athol Murphy from MIT, Jonah Creel from Karlsruhe Institute of Technology, and Nunnally Kessler from the University of Göttingen.
Among the many applications in the mailbox, these three have the best and outstanding resumes, and the top one is none other than Nunnally Kessler from the University of Göttingen.
This is a girl, majoring in particle physics. She has been an intern at CERN for a year and participated in the analysis and discovery of pentaquark particles in 2015.
If nothing unexpected happens, she will become a formal researcher at CERN next year.
Together with himself and Senior Brother Lin Feng who came from Princeton, five people from different countries formed a small temporary team.
Fortunately, everyone can speak English, so communication is no problem.
After gathering a group of people for a meal, the intense and orderly work is about to begin.
July 25th is coming soon.
CERN staff have prepared accelerated experiments, and they will use the SPS acceleration device to complete this experiment.
In this experiment, CERN staff will follow Xu Chuan's request to launch a beam of electrons at hydrogen molecules through an accelerator and measure the deflection process of some electrons.
This is somewhat different from the previous process of measuring the radius of protons in other laboratories.
Previous scattering experiments used high-energy electron beams, which had limited sensitivity to the proton radius and could only extrapolate to lower-energy electrons to determine the radius, but the lower energies that will be used this time circumvent this problem.
And to further improve accuracy, Xu Chuan asked CERN to inject hydrogen molecules directly into the vacuum tube carrying the electron beam, rather than placing the electron beam in a metal container as in many previous experiments.
This means that there will be no electrons hitting the metal and interfering with the measurement during the experiment, greatly improving the accuracy of the measurement.
Fortunately, CERN has a variety of advanced equipment that can complete this task as required.
If it were elsewhere, it would be a huge trouble to directly inject hydrogen molecules into a vacuum tube carrying an electron beam.
Such an experiment would be troublesome elsewhere, but at CERN it would be nothing more than a trivial collision experiment. Even though Xu Chuan made some requests, CERN engineers successfully completed the collision process in accordance with the requirements.
As for the collected data, it will be processed by CERN's supercomputer first. After the processing is completed, it will be transferred to CERN's database.
Then Xu Chuan applies for use. This is the overall workflow, which is somewhat similar to the use of public telescopes in the astronomical community.
On the morning of the 27th, Xu Chuan successfully obtained the data of this proton collision experiment from the staff of CERN.
Returning to the temporary office where the application was made, the four members of the team were already waiting here.
"Everyone, after the experimental data is available, we have something to do."
Xu Chuan clapped his hands and attracted the attention of several friends.
"Great, let's start early and give the proton a precise radius!"
In the office, Athol Murphy, an intern from MIT with long brown hair, grinned.
Xu Chuan smiled and said: "The drawing of the transition diagram between electron energy levels will be left to you."
Hearing this, the smile on Athol Murphy's face disappeared immediately, and he wailed: "Oh, no, my dear Xu, you can't bully me like this, you know I'm not good at this."< br>
"Compared with drawing transition maps between electron energy levels, I am better at analyzing raw data. Leave that to me and I will satisfy you."
Xu Chuan ignored Athol Murphy and started arranging work.
In fact, he was just joking. It was impossible for him to hand over the drawing of the transition diagram between electron energy levels to others. This was the core of the relationship calculation and could only be done by his own hands.
"OK, everyone's work has been arranged. Let's start working. I believe that these tasks are not difficult for you."
After arranging mathematical analysis work, the office suddenly became busy.
Calculating the charge radius data of protons is not a difficult task for the particle physics community, and predecessors have made countless efforts in this work.
Their current job is more like standing on the shoulders of giants and looking toward the future.
The days passed like this. In the CERN office, Xu Chuan led several recruited friends to work overtime to complete the compilation of experimental data.
In the blink of an eye, time came to August 5th.
"Xu, look at this, this physical image of the scattering of gravitons and protons seems to be somewhat abnormal."
In the office, Nunnally Kessler from the University of Göttingen called Xu Chuan.
Hearing the voice, Xu Chuan replied without raising his head: "Wait a moment while I complete the data analysis."
The work he was doing had reached a critical stage and it was impossible to put it down.
After waiting for more than ten minutes, Xu Chuan controlled the mouse to add a stroke to a half-completed jump map on the display screen, and then stood up after saving it.
"What's wrong, Nunnally?"
Walking to Nunnally Kessler, Xu Chuan asked aloud.
"Look at this, when the electron beam contacts the hydrogen molecular cloud, it is excited to the 3S state, and then they decay to the 2P state within 0.16μs, releasing detectable Balmer-α photons of 656nm. This is the same as usual There is something wrong with the proton radius measurement experiment," Nunnally Kessler said in front of the computer, pointing to a series of energy spectrum images on the display.
Hearing this, Xu Chuan looked over curiously.
Following the direction of Nunnally Kessler's finger, he indeed saw the abnormal data.
"Interestingly, judging from this data, the impact of the electron beam on the hydrogen molecular cloud seems to be smaller than in previous experiments, which means that the radius of the proton may be smaller than 0.84184 femtometers."
Staring at the image on the display screen, Xu Chuan's eyes flashed with light.
To him, the secrets contained in this image that is difficult for ordinary people to understand are like the emperor's new clothes, laid out in front of him.
After thinking for a while, Xu Chuan said: "Nunnally, complete the analysis of this data as soon as possible. Maybe we will get a new, smaller proton radius."
On the side, after hearing Xu Chuan's words, Nunnally Kessler was stunned for a moment and said in surprise: "Smaller proton radius? Is this possible?"
Xu Chuan smiled and said: "Nothing is impossible. Before the calculation of the proton's radius is completed through first principles, even if it is announced that the proton's radius is below 0.8 femtometers, it is normal."
"After all, we know so little about particles at the microscopic level, don't we?"
Hearing this, Nunnally Kessler's breathing suddenly became rapid.
If they find a smaller proton radius in this experiment, it means they can leave their name in the world of particle physics.
Even if this data may not be the final accurate data.
Anyway, in the current world of physics, there is no precise and certain value for the charge radius of a proton.
It is possible to obtain a smaller proton radius data, which is like giving this five-person team a shot of chicken blood.
They could be said to have worked overtime before, but now they have devoted all their time except eating and sleeping to data analysis.
With the support of this fiery state, finally, on August 11, Xu Chuan completed the final transition map between electron energy levels and calculated the proton radius measured in this experiment.
[The proton body radius is Rp. The shape factor of the energy and momentum tensor is detected through the scattering of gravitons and protons, and some new formulas for the properties of electrons and protons are introduced, as well as their physical meaning. The energy-to-charge ratio formula: mC/q=1/2εEds∫. =1/24πrεEr/4πrεE】
[It can be obtained that the detailed data of the circular motion associated with de Broglie waves, that is, the second level spin motion, is: 0.831×10-15m±0.0016fm. 】
At his desk, Xu Chuan completed the final calculation and obtained a brand new proton radius data.
0.831×10-15m±0.0016fm.
A proton charge radius that is the lowest ever.
It is far lower than the 0.879±0.011fm femtometer previously determined by the International Committee on Scientific and Technical Data in the physics community, and also lower than the 0.84184±0.00067fm measured by the Max Planck Institute of Quantum Optics.
"What's the data?"
"Has the radius of the proton been calculated?"
At the desk, after Xu Chuan completed the calculation, several other friends came over and asked nervously.
Xu Chuan picked up the calculation paper from the table and handed it over. Several friends behind him grabbed it.
“0.831 femtometer!”
"A new radius, we discovered a new history!"
"It's incredible that the radius of the proton can be reduced further. If we didn't get this data personally, I would definitely sneer at it."
Seeing the answer on the manuscript paper, the office immediately cheered.
For these CERN interns, nothing is more exciting than this. This is a great discovery.
Regardless of whether this data can be verified to be correct in the future, there is no doubt that now, they will become a central figure in the world of particle physics.