Meet the antiparticle that can reveal even hidden tumors in our body: what is a positron?

As the world of science develops every day with the help of technology, new concepts keep emerging. After the electron, proton and neutron, which are subatomic particles, we also met a particle called the positron. discovered nearly a hundred years ago. We call the first important example of the concept antiparticle to the positron possible to say.

Of course you can say as an ordinary person that banana is a positron, you are right because scientific studies interest us little as long as they remain theoretical. The positron is not one of them because, thanks to a technology with positron emission tomography, hidden tumors are revealed that are not easy to see in our body. Let’s take a closer look at questions like what is a positron, what is it for, what is it used for.

Let’s make a basic definition first; What is a Positron?

The positron, also called anti-electron, is considered to be the antimatter counterpart or antiparticle of the electron. It has the same mass as an electron. Annihilation occurs when an electron collides with a positron. In cases where the collision occurs at lower energies, two or more photons can be produced.

So how is the positron formed?

An interaction called positron emission radioactive decay, or the release of an energetic photon, It occurs when it interacts with another atom and produces double production. A positron is also emitted as a result of positive beta decay in the neutron-deficient radioactive core. Positron can be formed as a result of the decay of short-lived particles, or it can be produced by man.

Fine, but what does this positron do?

Namely; The positron, which is in a stable state in the vacuum, collides with the electron, causing annihilation. This extinction releases gamma rays. In other words, even if the positron is not used alone, the reactions it creates after interacting with other subatomic particles are used. The main examples of this are positron microscopy and positron emission tomography.

Much clearer images are obtained with the positron microscope:

According to an article published in the February 1998 issue of the Review of Scientific Instruments, Brandeis University, They developed the positron microscope, which took the scanning electron microscope a step further. This developed device was developed to produce a one-dimensional y-ray scan on 20 resolution targets.

A y-ray used in the positron microscope in this way is much more sensitive to large-scale defects. Because positron is much more easily trapped in sample defects. Devices called repositron emission microscopy, developed in the following years, increase the chance of observing specific contrasts. Studies on this topic are continuing.

Occult tumors become visible thanks to positron emission tomography:

Positron emission tomography, called PET for short, is one of the nuclear imaging methods. It is considered the most effective imaging method for tumors and metastases. because, unlike the known tomography methods, it allows the visualization of hidden tumors that are not clearly visible in our body.

The details are a bit complicated, but roughly speaking; in the patient before surgery There is a small amount of a radioactive substance called 18F. a sugary compound is administered intravenously. When positron emission tomography works, it detects these substances that have accumulated around the tumor cells. In other words, the tumor is exposed.

Do not be afraid to administer radioactive substances intravenously, because they have a very short life and It is excreted from the body in a very short time. Thanks to this advantage, the success of chemotherapy sessions can be observed in this way. In addition, the spread of tumors that are believed to have disappeared but are suspected of spreading to the body can be revealed in this way.

The story of the discovery of the positron is quite interesting:

A physicist named Paul Dirac discovered in 1928 that electrons were simultaneous published an article claiming that it can be both negatively and positively charged. The situation in question due to the sailor effect; He explained it with the Dirac equation, a kind of mixture of quantum mechanics, special relativity and spin concepts.

In fact, this article was not talking about a new particle, but that an existing electron could have two opposite charges in solution. A theoretical physicist named Hermann Weyl He talked about the possible mathematical consequences of this situation. Paul Dirac was a bit surprised by this mathematical model. Unlike the well-known quantum mechanics equations, the solution of negative energy in this equation could not be ignored. In addition, there was the possibility of a spontaneous jump between negative and positive charge.

In 1929 Paul Dirac wrote in an article. “An electron with negative energy moves in an external field as if it were carrying a positive charge.” posted the sentence. To eliminate the possibility of skipping we should have seen the void as a sea of ​​negative energy. Proton was an island in this sea. Finally, Dirac accepted the problem that the proton has a greater mass than the electron. Fortunately, there are several scientists researching the subject.

Positron: an electron that travels back in time

Robert Oppenheimer countered that the Dirac equation could be a solution to the negative electron. In 1931, Hermann Weyl, showed that the masses of negative electrons and positive electrons are the same. Dirac revised these two ideas and published a paper on the prediction of an as yet unobserved particle he called the anti-electron.

Estimated by Richard Phillips Feynman and Ernst Stueckelberg, Dirac they said the positron should actually be interpreted as a version of the electron going back in time and they reinterpreted the Dirac equation. Yoichiro Nambu reinterpreted this particle about generation and destruction and explained the contrast with the following sentence;

“The final creation and destruction of pairs that can take place now and later is not creation or extinction, but merely a change of direction of moving particles from the past to the future or from the future to the future.”

Also called anti-electrons What is a positron, what is it for, where is it used We answered common questions such as: Since the positron and other subatomic particles are an ocean with a high probability of drowning if they dive into it, in this article we have only shared the basic information that will satisfy people’s curiosity.